ubiquinone and idebenone

Coenzyme Q10 (ubiquinone or CoQ10) is a lipid molecule that acts as an electron mobile carrier of the electron transport chain and also contains antioxidant properties. Supplementation of CoQ10 has been very useful to treat mitochondrial diseases. CoQ10 along with its synthetic analogue, idebenone, is used largely to treat various neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, Amyotrophic lateral sclerosis, and Friedreich's ataxia and additional brain disease condition like autism, multiple sclerosis, epilepsy, depression, and bipolar disorder, which are related to mitochondrial impairment. In this article, we have reviewed numerous physiological functions of CoQ10 and the rationale for its use in clinical practice in different brain disorders.

Topics: Animals; Antioxidants; Brain Diseases; Humans; Mitochondria; Mitochondrial Diseases; Neurodegenerative Diseases; Ubiquinone

Idebenone is a well described drug that was initially developed against dementia. The current literature widely portrays this molecule as a potent antioxidant and CoQ

Topics: Antioxidants; Ubiquinone

Mitochondria play a vital role in cellular metabolism and are central mediator of intracellular signalling, cell differentiation, morphogenesis and demise. An increasingly higher number of pathologies is linked with mitochondrial dysfunction, which can arise from either genetic defects affecting core mitochondrial components or malfunctioning pathways impairing mitochondrial homeostasis. As such, mitochondria are considered an important target in several pathologies spanning from neoplastic to neurodegenerative diseases as well as metabolic syndromes. In this review we provide an overview of the state-of-the-art in mitochondrial pharmacology, focusing on the novel compounds that have been generated in the bid to correct mitochondrial aberrations. Our work aims to serve the scientific community working on translational medical science by highlighting the most promising pharmacological approaches to target mitochondrial dysfunction in disease.

Topics: Antioxidants; Humans; Mitochondria; Mitochondrial Diseases; Mitochondrial Dynamics; Neurodegenerative Diseases; Oxidative Phosphorylation; Pyrazines; Ubiquinone

Respiratory failure is the principal source of morbidity and mortality among patients with Duchenne muscular dystrophy exerting a negative influence on their total quality of life. The aim of this review is to provide systematically current literature evidence about the effects of different treatment options (available or under development) for Duchenne muscular dystrophy on the pulmonary function of these patients.. A comprehensive search was undertaken using multiple health-related databases, while two independent reviewers assessed the eligibility of studies. A third person addressed any disagreements between reviewers. The quality of the methodology of the included studies was also assessed.. A total of 19 original research papers (nine evaluating the role of steroids, six idebenone, three eteplirsen, one stem-cell therapy, and one ataluren) were found to fulfill our selection criteria with the majority of them (14 of 19) being prospective studies, not always including a control group. Endpoints mainly used in these studies were values of pulmonary function tests. Current and under development treatments proved to be safe and no significant adverse events were reported. A beneficial impact on pulmonary function was described by authors in the majority of these studies. The principal effect was slowing of lung disease progress, as expressed by spirometric values. However, the risk of bias was introduced in many of the above studies, while high heterogeneity in terms of treatment protocols and outcome measures limits the comparability of the results.. Glucocorticoids remain the best-studied pharmacologic therapy for Duchenne muscular dystrophy and very likely delay the expected decline in lung function. With regard to new therapeutic agents, initial study results are encouraging. However, larger clinical trials are needed that minimize the risk of study bias, optimize the comparability of treatment groups, examine clinically meaningful pulmonary outcome measures, and include long-term follow up.

Topics: Glucocorticoids; Humans; Lung; Male; Morpholinos; Muscular Dystrophy, Duchenne; Prospective Studies; Quality of Life; Respiratory Function Tests; Ubiquinone

The purpose of this review is to present the current and emerging treatment alternatives for Leber's hereditary optic neuropathy (LHON), emphasizing the most recent use of idebenone and stem cells or gene therapy.. A comprehensive literature review was performed at the PubMed database regarding the various treatment modalities for LHON.. Treatment modalities for LHON include nutritional supplements, activators of mitochondrial biogenesis, brimonidine, and symptomatic and supportive treatment, but nowadays attention is being paid to idebenone and gene therapy or stem cells.. The treatment of LHON remains challenging, given the nature of the disease and its prognosis.

Topics: Antioxidants; Genetic Therapy; Humans; Optic Atrophy, Hereditary, Leber; Stem Cell Transplantation; Treatment Outcome; Ubiquinone

The dystrophinopathies include Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), and X-linked dilated cardiomyopathy (XLDCM). In recent years, co-ordinated multidisciplinary management for these diseases has improved the quality of care, with early corticosteroid use prolonging independent ambulation, and the routine use of non-invasive ventilation signficantly increasing survival. The next target to improve outcomes is optimising treatments to delay the onset or slow the progression of cardiac involvement and so prolong survival further.. To assess the effects of interventions for preventing or treating cardiac involvement in DMD, BMD, and XLDCM, using measures of change in cardiac function over six months.. On 16 October 2017 we searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE and Embase, and on 12 December 2017, we searched two clinical trials registries. We also searched conference proceedings and bibliographies.. We considered only randomised controlled trials (RCTs), quasi-RCTs and randomised cross-over trials for inclusion. In the Discussion, we reviewed open studies, longitudinal observational studies and individual case reports but only discussed studies that adequately described the diagnosis, intervention, pretreatment, and post-treatment states and in which follow-up lasted for at least six months.. Two authors independently reviewed the titles and abstracts identified from the search and performed data extraction. All three authors assessed risk of bias independently, compared results, and decided which trials met the inclusion criteria. They assessed the certainty of evidence using GRADE criteria.. We included five studies (N = 205) in the review; four studies included participants with DMD only, and one study included participants with DMD or BMD. All studied different interventions, and meta-analysis was not possible. We found no studies for XLDCM. None of the trials reported cardiac function as improved or stable cardiac versus deteriorated.The randomised first part of a two-part study of perindopril (N = 28) versus placebo (N = 27) in boys with DMD with normal heart function at baseline showed no difference in the number of participants with a left ventricular ejection fraction (LVEF%) of less than 45% after three years of therapy (n = 1 in each group; risk ratio (RR) 1.04, 95% confidence interval (CI) 0.07 to 15.77). This result is uncertain because of study limitations, indirectness and imprecision. In a non-randomised follow-up study, after 10 years, more participants who had received placebo from the beginning had reduced LVEF% (less than 45%). Adverse event rates were similar between the placebo and treatment groups (low-certainty evidence).A study comparing treatment with lisinopril versus losartan in 23 boys newly diagnosed with Duchenne cardiomyopathy showed that after 12 months, both were equally effective in preserving or improving LVEF% (lisinopril 54.6% (standard deviation (SD) 5.19), losartan 55.2% (SD 7.19); mean difference (MD) -0.60% CI -6.67 to 5.47: N = 16). The certainty of evidence was very low because of very serious imprecision and study limitations (risk of bias). Two participants in the losartan group were withdrawn due to adverse events: one participant developed an allergic reaction, and a second exceeded the safety standard with a fall in ejection fraction greater than 10%. Authors reported no other adverse events related to the medication (N = 22; very low-certainty evidence).A study comparing idebenone versus placebo in 21 boys with DMD showed little or no difference in mean change in cardiac function between the two groups from baseline to 12 months; for fractional shortening the mean change was 1.4% (SD 4.1) in the idebenone group and 1.6% (SD 2.6) in the placebo group (MD -0.20%, 95% CI -3.07 to 2.67, N = 21), and for ejection fraction the mean change was -1.9% (SD 9.8) in the idebenone group and 0.4% (SD 5.5) in the placebo group (MD -2.30%, 95% CI -9.18 to 4.58, N = 21). The certainty of evidence was very low because of study limitations and very serious imprecision. Reported adverse events were similar between. Based on the available evidence from RCTs, early treatment with ACE inhibitors or ARBs may be comparably beneficial for people with a dystrophinopathy; however, the certainty of evidence is very low. Very low-certainty evidence indicates that adding eplerenone might give additional benefit when early cardiomyopathy is detected. No clinically meaningful effect was seen for growth hormone or idebenone, although the certainty of the evidence is also very low.

Topics: Adolescent; Adult; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Antihypertensive Agents; Cardiomyopathies; Cardiomyopathy, Dilated; Cardiovascular Agents; Child; Disease Progression; Eplerenone; Human Growth Hormone; Humans; Lisinopril; Losartan; Male; Muscular Dystrophy, Duchenne; Non-Randomized Controlled Trials as Topic; Perindopril; Placebos; Randomized Controlled Trials as Topic; Stroke Volume; Ubiquinone; Young Adult

Topics: Antioxidants; Clinical Trials as Topic; Friedreich Ataxia; Humans; Optic Atrophy, Hereditary, Leber; Ubiquinone

Idebenone is a rapidly absorbed, safe and well-tolerated drug and is currently the only clinically proven treatment option for Leber's hereditary optic neuropathy (LHON) patients. Idebenone (Raxone®) is approved by the European Medicines Agency for the treatment of LHON and has been available on the European market since 2015. Due to its molecular mode of action of bypassing the defective mitochondrial complex I, idebenone leads to improved energy supply and a functional recovery of retinal ganglion cells during the acute stage of the disease, thereby preventing further vision loss and promoting recovery of vision. Thus, commencing treatment shortly after the onset of symptoms is likely to have the best therapeutic effect, a hypothesis that is supported by the available clinical data.

Topics: Antioxidants; Humans; Optic Atrophy, Hereditary, Leber; Ubiquinone

Friedreich ataxia is a rare inherited autosomal recessive neurological disorder, characterised initially by unsteadiness in standing and walking, slowly progressing to wheelchair dependency usually in the late teens or early twenties. It is associated with slurred speech, scoliosis, and pes cavus. Heart abnormalities cause premature death in 60% of people with the disorder. There is no easily defined clinical or biochemical marker and no known treatment. This is the second update of a review first published in 2009 and previously updated in 2012.. To assess the effects of pharmacological treatments for Friedreich ataxia.. On 29 February 2016 we searched The Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, EMBASE and CINAHL Plus. On 7 March 2016 we searched ORPHANET and TRIP. We also checked clinical trials registers for ongoing studies.. We considered randomised controlled trials (RCTs) or quasi-RCTs of pharmacological treatments (including vitamins) in people with genetically-confirmed Friedreich ataxia. The primary outcome was change in a validated Friedreich ataxia neurological score after 12 months. Secondary outcomes were changes in cardiac status as measured by magnetic resonance imaging or echocardiography, quality of life, mild and serious adverse events, and survival. We excluded trials of duration shorter than 12 months.. Three review authors selected trials and two review authors extracted data. We obtained missing data from the two RCTs that met our inclusion criteria. We collected adverse event data from included studies. We used standard methodological procedures expected by Cochrane.. We identified more than 12 studies that used antioxidants in the treatment of Friedreich ataxia, but only two small RCTs, with a combined total of 72 participants, both fulfilled the selection criteria for this review and published results. One of these trials compared idebenone with placebo, the other compared high-dose versus low-dose coenzyme Q10 and vitamin E (the trialists considered the low-dose medication to be the placebo). We identified two other completed RCTs, which remain unpublished; the interventions in these trials were pioglitazone (40 participants) and idebenone (232 participants). Other RCTs were of insufficient duration for inclusion.In the included studies, the primary outcome specified for the review, change in a validated Friedreich ataxia rating score, was measured using the International Co-operative Ataxia Rating Scale (ICARS). The results did not reveal any significant difference between the antioxidant-treated and the placebo groups (mean difference 0.79 points, 95% confidence interval -1.97 to 3.55 points; low-quality evidence).The published included studies did not assess the first secondary outcome, change in cardiac status as measured by magnetic resonance imaging. Both studies reported changes in cardiac measurements assessed by echocardiogram. The ejection fraction was not measured in the larger of the included studies (44 participants). In the smaller study (28 participants), it was normal at baseline and did not change with treatment. End-diastolic interventricular septal thickness showed a small decrease in the smaller of the two included studies. In the larger included study, there was no decrease, showing significant heterogeneity in the study results; our overall assessment of the quality of evidence for this outcome was very low. Left ventricular mass (LVM) was only available for the smaller RCT, which showed a significant decrease. The relevance of this change is unclear and the quality of evidence low.There were no deaths related to the treatment with antioxidants. We considered the published included studies at low risk of bias in six of seven domains assessed. One unpublished included RCT, a year-long study using idebenone (232 participants), published an interim report in May 2010 stating that the study reached neither its primary endpoint, which was change in the ICARS score, nor a key cardiological secondary endpoint, but data were not available for verification and analysis.. Low-quality evidence from two small, published, randomised controlled trials neither support nor refute an effect from antioxidants (idebenone, or a combination of coenzyme Q10 and vitamin E) on the neurological status of people with Friedreich ataxia, measured with a validated neurological rating scale. A large unpublished study of idebenone that reportedly failed to meet neurological or key cardiological endpoints, and a trial of pioglitazone remain unpublished, but on publication will very likely influence quality assessments and conclusions. A single study of idebenone provided low-quality evidence for a decrease in LVM, which is of uncertain clinical significance but of potential importance that needs to be clarified. According to low-quality evidence, serious and non-serious adverse events were rare in both antioxidant and placebo groups. No non-antioxidant agents have been investigated in RCTs of 12 months' duration.

Topics: Antioxidants; Friedreich Ataxia; Heart; Humans; Hypertrophy, Left Ventricular; Randomized Controlled Trials as Topic; Rare Diseases; Ubiquinone; Ultrasonography; Vitamin E

Ubiquinone, commonly called coenzyme Q10 (CoQ), is a lipophilic electron carrier and endogenous antioxidant found in all cellular membranes. In the mitochondrial inner membrane it transfers electrons to complex III of the electron transport chain. The short chain CoQ analogue idebenone is in clinical trials for a number of diseases that exhibit a mitochondrial etiology. Nevertheless, evidence that idebenone ameliorates neurological symptoms in human disease is inconsistent. Although championed as an antioxidant, idebenone can also act as a pro-oxidant by forming an unstable semiquinone at complex I. The antioxidant function of idebenone is critically dependent on two-electron reduction to idebenol without the creation of unstable intermediates. Recently, cytoplasmic. quinone oxidoreductase 1 (NQO1) was identified as a major enzyme catalyzing idebenone reduction. While reduction allows idebenone to act as an antioxidant, evidence also suggests that NQO1 enables idebenone to shuttle reducing equivalents from cytoplasmic NAD(P)H to mitochondrial complex III, bypassing any upstream damage to the electron transport chain. In this mini-review we discuss how idebenone can influence mitochondrial function within the context of cytoprotection. Importantly, in the brain NQO1 is expressed primarily by glia rather than neurons. As NQO1 is an inducible enzyme regulated by oxidative stress and the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway, optimizing NQO1 expression in appropriate cell types within a specific disease context may be key to delivering on idebenone's therapeutic potential.

Topics: Animals; Antioxidants; Electron Transport Complex I; Electron Transport Complex III; Humans; NAD(P)H Dehydrogenase (Quinone); Neuroprotective Agents; Oxidants; Oxidation-Reduction; Ubiquinone

Friedreich's ataxia (FA) is associated with progressive cardiac hypertrophy resulting from a genetic abnormality in the frataxin gene. Cardiac involvement is the most common cause of death (59%) in FA patients. Cardiac related death occurs at a significantly younger age than non-cardiac related death. Idebenone is a short-chain quinone analogue with a potent free-radical scavenger action. This drug has the potential to preserve and even improve mitochondrial function.Studies on Idebenone treatment showed rather conflicting results on FA cardiomyopathy. The present article reviews the clinical features of FA cardiomyopathy, imaging techniques used to diagnose, follow and monitor therapy which aimed to revert FA cardiomyopathy.

Topics: Friedreich Ataxia; Heart; Heart Function Tests; Humans; Ubiquinone

Coenzyme Q10 is a ubiquitous component of cellular membranes and belongs to the class of benzoquinones that mainly differ with regards to the length and composition of their hydrophobic tail. The characteristic quinone group can accept electrons from various biological sources and is converted by a one electron transfer to the unstable semiquinone or by a two electron transfer to the more stable hydroquinone. This feature makes CoQ10 the bona fide cellular electron transfer molecule within the mitochondrial respiratory chain and also makes it a potent cellular antioxidant. These activities serve as justification for its popular use as food supplement. Another quinone with similarities to the naturally occurring CoQ10 is idebenone, which shares its quinone moiety with CoQ10, but at the same time differs from CoQ10 by the presence of a much shorter, less lipophilic tail. However, despite its similarity to CoQ10, idebenone cannot be isolated from any natural sources but instead was synthesized and selected as a pharmacologically active compound in the 1980s by Takeda Pharmaceuticals purely based on its pharmacological properties. Several recent clinical trials demonstrated some therapeutic efficacy of idebenone in different indications and as a consequence, many practitioners question if the freely available CoQ10 could not be used instead. Here, we describe the molecular and pharmacological features of both molecules that arise from their structural differences to answer the question if idebenone is merely a CoQ10 analogue as frequently perpetuated in the literature or a pharmaceutical drug with entirely different features.

Topics: Adenosine Triphosphate; Antioxidants; Biological Products; Electron Transport; Humans; Membrane Potential, Mitochondrial; Mitochondria; Molecular Weight; NAD(P)H Dehydrogenase (Quinone); Structure-Activity Relationship; Ubiquinone

To discuss recent advances in potential treatments for Leber hereditary optic neuropathy (LHON), a typically visually devastating hereditary optic neuropathy caused by mutations in the mitochondrial genome.. Idebenone has been proposed as a means of bypassing defective complex I activity and a free radical scavenger to prevent oxidative damage. EPI-743 may have more potency than idebenone, but no clinical trials have been performed. Gene therapy techniques have advanced significantly, including allotopic expression and nuclear transfer. Successful rescue of animal models of LHON with both of these therapies has been demonstrated. Introduction of exogenous DNA into the mitochondrial genome with mitochondrial targeting of viral vectors is another promising technique.. There are currently no proven treatments for LHON. However, there are many promising novel treatment modalities that are currently being evaluated, with several clinical trials underway or in the planning stages. Supportive measures and genetic counseling remain of great importance for these patients.

Topics: Animals; Genetic Counseling; Genetic Therapy; Humans; Mitochondria; Optic Atrophy, Hereditary, Leber; Ubiquinone

Neurodegenerative movement disorders mainly include Parkinson's disease (PD), atypical parkinsonisms, Huntington's disease (HD), and Friedreich's ataxia (FA). With mitochondrial dysfunction observed in these diseases, mitochondrial enhancement such as creatine, coenzyme Q10 (CoQ10) and its analogues (idebenone and mitoquinone) has been regarded as a potential treatment.. In this paper, we systematically analysed and summarized the efficacy of mitochondrial enhancement in improving motor and other symptoms in neurodegenerative movement disorders.. We searched the electronic databases PubMed, EMBASE, CINAHL, Cochrane Library and China National Knowledge Infrastructure until September 2013 for eligible randomized controlled trials (RCTs), as well as unpublished and ongoing trials. We calculated the mean differences for continuous data with 95% confidence intervals and pooled the results using a fixed-effect model, if no significant statistical heterogeneity was found (I(2) < 50%).. We included 16 studies with 1,557 randomized patients, which compared creatine, CoQ10 or its analogues with placebo in motor and other symptoms. No significant improvements were found in the motor symptoms of PD, atypical parkinsonisms or HD patients, while only the high dose of idebenone seems to be promising for motor improvement in FA. Certain benefits are found in other symptoms.. There is insufficient evidence to support the use of mitochondrial enhancement in patients with neurodegenerative movement disorders. More well-designed RCTs with large samples are required for further confirmation.

Topics: Animals; Creatine; Dose-Response Relationship, Drug; Humans; Mitochondria; Mitochondrial Diseases; Neurodegenerative Diseases; Organophosphorus Compounds; Randomized Controlled Trials as Topic; Ubiquinone

Treatment of mitochondrial respiratory chain (MRC) disorders is extremely difficult, however, coenzyme Q10 (CoQ10) and its synthetic analogues are the only agents which have shown some therapeutic benefit to patients. CoQ10 serves as an electron carrier in the MRC as well as functioning as a potent lipid soluble antioxidant. CoQ10 supplementation is fundamental to the treatment of patients with primary defects in the CoQ10 biosynthetic pathway. The efficacy of CoQ10 and its analogues in the treatment of patients with MRC disorders not associated with a CoQ10 deficiency indicates their ability to restore electron flow in the MRC and/or increase mitochondrial antioxidant capacity may also be important contributory factors to their therapeutic potential.

Topics: Animals; Ataxia; Humans; Mitochondrial Diseases; Molecular Structure; Muscle Weakness; Treatment Outcome; Ubiquinone

Leber's hereditary optic neuropathy is a rare genetic disorder affecting the retinal ganglion cells leading to a persistent severe bilateral loss of visual acuity within weeks or months. Males are much more likely to be affected than females, disease onset in most cases takes place between age 15 and 35 years. The disease is caused by point mutations in the mitochondrial DNA. The penetrance of the disease is incomplete, i.e., not all mutation carriers develop clinical symptoms. The phenotype is relatively uniform, but age at onset, severity and prognosis may vary even within the same family. Environmental and endocrine factors, optic disc anatomy as well as mitochondrial and nuclear genetic factors are discussed to influence penetrance as well as interindividual and intrafamilial variability. However, only cigarette smoking and excessive alcohol consumption have been shown to trigger disease onset. The disease is characterised by a central visual field defect, impaired colour vision and fundoscopically a peripapillary microangiopathy in the acute phase. Most patients end up after some months with a severe visual loss below 0.1 and in most cases there is no significant improvement of visual acuity in the course. In rare cases patients experience a mostly partial visual recovery which depends on the type of mutation. For confirmation of the diagnosis a detailed ophthalmological examination with fundoscopy, family history and genetic analysis of the mitochondrial DNA is needed. To date, there is no proven causal therapy, but at early disease stages treatment with idebenone can be tried.

Topics: Antioxidants; DNA, Mitochondrial; Genetic Predisposition to Disease; Humans; Molecular Diagnostic Techniques; Mutation; Optic Atrophy, Hereditary, Leber; Ubiquinone

Many human childhood mitochondrial disorders result from abnormal mitochondrial DNA (mtDNA) and altered bioenergetics. These abnormalities span most of the mtDNA, demonstrating that there are no "unique" positions on the mitochondrial genome that when deleted or mutated produce a disease phenotype. This diversity implies that the relationship between mitochondrial genotype and clinical phenotype is very complex. The origins of clinical phenotypes are thus unclear, fundamentally difficult-to-treat, and are usually clinically devastating. Current treatment is largely supportive and the disorders progress relentlessly causing significant morbidity and mortality. Vitamin supplements and pharmacological agents have been used in isolated cases and clinical trials, but the efficacy of these interventions is unclear. In spite of recent advances in the understanding of the pathogenesis of mitochondrial diseases, a cure remains elusive. An optimal cure would be gene therapy, which involves introducing the missing gene(s) into the mitochondria to complement the defect. Our recent research results indicate the feasibility of an innovative protein-transduction ("protofection") technology, consisting of a recombinant mitochondrial transcription factor A (TFAM) that avidly binds mtDNA and permits efficient targeting into mitochondria in situ and in vivo. Thus, the development of gene therapy for treating mitochondrial disease offers promise, because it may circumvent the clinical abnormalities and the current inability to treat individual disorders in affected individuals. This review aims to focus on current treatment options and future therapeutics in mitochondrial disease treatment with a special emphasis on Leber's hereditary optic neuropathy.

Topics: Animals; Antioxidants; Dietary Supplements; Disease Models, Animal; DNA-Binding Proteins; DNA, Mitochondrial; Female; Genetic Therapy; Humans; Male; Mitochondria; Mitochondrial Proteins; Mutation; Optic Atrophy, Hereditary, Leber; Oxidative Stress; Phenotype; Recombinant Proteins; Transcription Factors; Ubiquinone

Chronic sun exposure causes photoaging, the appearance of prematurely aged skin. This phenomenon is characterized by progressive alteration of the dermal extracellular matrix, including elastin and collagen fibers. While many cosmeceuticals claim to improve the appearance of photoaged skin, data are lacking regarding their ability to induce molecular responses associated with wrinkle effacement, particularly increased collagen production.. To conduct a meta-analysis to determine whether there was a factor(s) that could predict response to various cosmeceuticals.. Hundred subjects enrolled in five separate studies of cosmeceuticals containing: L-ascorbic acid, pentapeptide, α-lipoic acid, yeast extract, or 1% idebenone. Five groups consisting of 16-20 volunteers applied one cosmeceutical to their photodamaged forearms for several weeks. Punch biopsies were obtained pretreatment and post-treatment and analyzed for type I procollagen by ELISA.. Analysis of basal collagenesis reinforced the notion that hypo-collagenesis is associated with photoaging severity, independent of age or gender. Treatment outcome varied greatly among subjects, ranging from no improvement to a 7-fold increase in collagenesis. Retrospective statistical meta-analysis was conducted to determine whether age, gender, type of cosmeceutical, or evidence of hypo-collagenesis in untreated skin could predict responsiveness to cosmeceuticals. Our analysis revealed that subjects with hypo-collagenesis responded 6.4 times more often than subjects with normo-collagenesis.. Hypo-collagenesis was the only factor that influenced treatment outcome. This study therefore identifies hypo-collagenesis as the unique parameter predicting anti-aging cosmeceutical treatment outcome. These findings provide a basis for future cosmetic testing and the potential development of custom formula skin care.

Topics: Aged; Aged, 80 and over; Antioxidants; Ascorbic Acid; Cell Extracts; Cosmetics; Female; Humans; Male; Middle Aged; Procollagen; Protein Biosynthesis; Skin; Skin Aging; Thioctic Acid; Ubiquinone; Yeasts

Friedreich's ataxia is a debilitating progressive neurodegenerative disease associated with cardiomyopathy and other features. The underlying cause is a deficiency of the mitochondrial protein frataxin which causes mitochondrial iron deposition, increased oxidative stress and impaired adenosine triphosphate production. Over the last 15 years, multiple clinical trials have assessed the efficacy of antioxidant agents in this disease. This article reviews trials of the two most important agents, namely co-enzyme Q10 and idebenone.

Topics: Antioxidants; Friedreich Ataxia; Humans; Ubiquinone

Over the last 15 years, some 16 open and controlled clinical trials for potential treatments of mitochondrial diseases have been reported or are in progress, and are summarized and reviewed herein. These include trials of administering dichloroacetate (an activator of pyruvate dehydrogenase complex), arginine or citrulline (precursors of nitric oxide), coenzyme Q10 (CoQ10; part of the electron transport chain and an antioxidant), idebenone (a synthetic analogue of CoQ10), EPI-743 (a novel oral potent 2-electron redox cycling agent), creatine (a precursor of phosphocreatine), combined administration (of creatine, α-lipoate, and CoQ10), and exercise training (to increase muscle mitochondria). These trials have included patients with various mitochondrial disorders, a selected subcategory of mitochondrial disorders, or specific mitochondrial disorders (Leber hereditary optic neuropathy or mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes). The trial designs have varied from open-label/uncontrolled, open-label/controlled, or double-blind/placebo-controlled/crossover. Primary outcomes have ranged from single, clinically-relevant scores to multiple measures. Eight of these trials have been well-controlled, completed trials. Of these only 1 (treatment with creatine) showed a significant change in primary outcomes, but this was not reproduced in 2 subsequent trials with creatine with different patients. One trial (idebenone treatment of Leber hereditary optic neuropathy) did not show significant improvement in the primary outcome, but there was significant improvement in a subgroup of patients. Despite the paucity of benefits found so far, well-controlled clinical trials are essential building blocks in the continuing search for more effective treatment of mitochondrial disease, and current trials based on information gained from these prior experiences are in progress. Because of difficulties in recruiting sufficient mitochondrial disease patients and the relatively large expense of conducting such trials, advantageous strategies include crossover designs (where possible), multicenter collaboration, and the selection of very few, clinically relevant, primary outcomes.

Topics: Antioxidants; Arginine; Clinical Trials as Topic; Creatine; Exercise Therapy; Humans; Mitochondrial Diseases; Ubiquinone

A 31-year-old woman developed subacute bilateral visual loss over a 2-week period. Two months later, the diagnosis of Leber hereditary optic neuropathy (LHON) 11778/ND4 was established and the patient was treated with 900 mg of idebenone daily. Over the ensuing 9 months, visual acuity improved from 20/200 to 20/25 in each eye with near-total resolution in visual field abnormalities. Our case report is in agreement with 2 large published series of patients with LHON treated with idebenone, raising hope for treatment of this visually devastating mitochondrial disorder.

Topics: Adult; Antioxidants; Clinical Trials as Topic; Female; Humans; Optic Atrophy, Hereditary, Leber; Prospective Studies; Recovery of Function; Retrospective Studies; Treatment Outcome; Ubiquinone

Topics: Adenosine Triphosphate; Cyclosporine; Enzyme Replacement Therapy; Humans; Mitochondria; Mitochondrial Diseases; Mutation; Phenotype; Ubiquinone

Friedreich ataxia is a rare inherited autosomal recessive neurological disorder, characterised initially by unsteadiness in standing and walking, slowly progressing to wheelchair dependency usually in the late teens or early twenties. It is associated with slurred speech, scoliosis and pes cavus. Heart abnormalities cause premature death in 60% to 80% of people with the disorder. There is no easily defined clinical or biochemical marker and no known treatment. This is the first update of a review published in 2009.. To examine the efficacy of antioxidants and other pharmacological treatments for Friedreich ataxia.. We searched The Cochrane Neuromuscular Disease Group Specialized Register (11 July 2011), CENTRAL (2011, Issue 3), MEDLINE (January 1966 to July 2011), EMBASE (January 1980 to July 2011), AMED (January 1985 to July 2011), CINAHL Plus (January 1937 to July 2011), LILACS (January 1982 to July 2011), ORPHANET (1990 to July 2011), TRIP (1998 to July 2011) and PEDRO (October 1999 to July 2011).. Randomised controlled trials (RCTs) or quasi-RCTs of drug treatment in people with genetically confirmed Friedreich ataxia. The primary outcome was change in ataxia rating scale as measured by the International Co-operative Ataxia Rating Scale (ICARS) after 12 months. Secondary outcomes included change in left ventricular heart mass as measured by magnetic resonance imaging or echocardiography. We excluded trials of shorter duration than 12 months.. Three authors selected the trials and two authors extracted data. We obtained missing data from the one RCT that met our inclusion criteria. We planned to collect adverse event data from included studies.. More than 10 studies used idebenone in the treatment of Friedreich ataxia but only one small RCT, with 29 participants, using the synthetic antioxidant idebenone 5 mg/kg, fulfilled the selection criteria for this review. Other RCTs were of insufficient duration. We identified no additional RCT when the searches were updated in 2011. In the included study, the primary outcome specified for this review, change in ICARS scale, did not reveal any significant differences with idebenone treatment compared to placebo. The secondary outcome of change in left ventricular heart mass index as measured by magnetic resonance spectroscopy was not assessed. The second secondary outcome, change in left ventricular mass as measured by echocardiography, did improve significantly; there was a 10.7% worsening after 12 months of treatment in the placebo group and a 5.6% improvement in the idebenone group. The mean difference was 16.37% (95% CI 95% 2% to 31%). There were no adverse events. We considered the included study at low risk of bias in five of the seven domains assessed. A larger trial using idebenone published an interm report in May 2010 stating that the study had failed to reach its primary endpoint, which was change in the ICARS scale.. No RCT using idebenone or any other pharmacological treatment has shown significant benefit on neurological symptoms associated with Friedreich ataxia. Idebenone has shown a positive effect on left ventricular heart mass but the clinical relevance of this change was not assessed in the included study.

Topics: Antioxidants; Friedreich Ataxia; Humans; Hypertrophy, Left Ventricular; Randomized Controlled Trials as Topic; Rare Diseases; Ubiquinone; Ultrasonography

Idebenone (IDE) is an antioxidant compound, structurally related to coenzyme Q10. Its therapeutic potential is growing in different application areas, as demonstrated by the number of experimental works and patents produced in very recent years.. Cyclodextrin inclusion complexes, liposomes, microemulsions, prodrugs, polymeric and lipid nanoparticles have been explored to achieve different goals, such as topical administration, brain targeting or increasing the bioavailability of this highly lipophilic drug. This review summarizes the results of works published in the last 20 years for the delivery and targeting of this drug.. A direct comparison of the different carrier systems is not easy and could not even be significant, due to the large variables existing among them. However, the different forms of delivery can help increase idebenone solubility, stability and biochemical activity. Further studies will be developed in order to improve the controlled release and targeting of idebenone.

Topics: Administration, Topical; Animals; Antioxidants; Biological Availability; Drug Delivery Systems; Humans; Lipids; Liposomes; Nanoparticles; Polymers; Prodrugs; Solubility; Ubiquinone

Reactive oxygen species (ROS) are widely believed to cause or aggravate several human pathologies such as neurodegenerative diseases, cancer, stroke and many other ailments. Antioxidants are assumed to counteract the harmful effects of ROS and therefore prevent or treat oxidative stress-related diseases. In this report, recent human studies exploring the efficiency of antioxidants in prevention and treatment of various diseases are reviewed. Few antioxidants including edaravone (for ischemic stroke in Japan), Nacetylcysteine (for acetaminophen toxicity), alfa-lipoic acid (for diabetic neuropathy) and some flavonoids (polyphenolic compounds present in dietary plants), such as micronized purified flavonoid fraction (diosmin and hesperidin) and oxerutins (for chronic venous insufficiency) as well as baicalein and catechins (for osteoarthritis) have found accepted clinical use. However, despite much enthusiasm in the 1980s and 1990s, many well-known agents such as antioxidant vitamins and also more recently developed compounds such as nitrones have not successfully passed the scrutiny of clinical trials for prevention and treatment of various diseases. This has given rise to a pessimistic view of antioxidant therapy, however, the evidence from human epidemiological studies about the beneficial effects of dietary antioxidants and preclinical in vitro and animal data are compelling. We have probably wasted too much time on agents like antioxidant vitamins instead of focusing on more disease specific, target-directed, highly bioavailable antioxidants. We here discuss possible reasons for the lack of success in some clinical trials and seek to provide some suggestions to be considered if antioxidant therapy is to succeed as an effective therapeutic strategy.

Topics: Acetylcysteine; Animals; Antioxidants; Antipyrine; Ascorbic Acid; Edaravone; Humans; Polyphenols; Thioctic Acid; Ubiquinone; Vitamin A; Vitamin E

Coenzyme Q10 (CoQ10, or ubiquinone) is an electron carrier of the mitochondrial respiratory chain (electron transport chain) with antioxidant properties. In view of the involvement of CoQ10 in oxidative phosphorylation and cellular antioxidant protection a deficiency in this quinone would be expected to contribute to disease pathophysiology by causing a failure in energy metabolism and antioxidant status. Indeed, a deficit in CoQ10 status has been determined in a number of neuromuscular and neurodegenerative disorders. Primary disorders of CoQ10 biosynthesis are potentially treatable conditions and therefore a high degree of clinical awareness about this condition is essential. A secondary loss of CoQ10 status following HMG-Coa reductase inhibitor (statins) treatment has be implicated in the pathophysiology of the myotoxicity associated with this pharmacotherapy. CoQ10 and its analogue, idebenone, have been widely used in the treatment of neurodegenerative and neuromuscular disorders. These compounds could potentially play a role in the treatment of mitochondrial disorders, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, Friedreich's ataxia, and other conditions which have been linked to mitochondrial dysfunction. This article reviews the physiological roles of CoQ10, as well as the rationale and the role in clinical practice of CoQ10 supplementation in different neurological and muscular diseases, from primary CoQ10 deficiency to neurodegenerative disorders. We also briefly report a case of the myopathic form of CoQ10 deficiency.

Topics: Animals; Humans; Mitochondrial Diseases; Neurodegenerative Diseases; Neuromuscular Diseases; Ubiquinone

While many treatments for mitochondrial electron transport (respiratory) chain disorders have been suggested, relatively few have undergone controlled clinical trials. This review focuses on the recent history of clinical trials of dichloroacetate (DCA), arginine, coenzyme Q(10), idebenone, and exercise in both primary (congenital) disorders and secondary (degenerative) disorders. Despite prior clinical impressions that DCA had a positive effect on mitochondrial disorders, two trials of diverse subjects failed to demonstrate a clinically significant benefit, and a trial of DCA in MELAS found a major negative effect of neuropathy. Arginine also has been used to treat MELAS with promising effects, although a controlled trial is still needed for this potentially toxic agent. The anti-oxidant coenzyme Q(10) is very widely used for primary mitochondrial disorders but has not yet undergone a controlled clinical trial; such a trial is now underway, as well as trials of the co-Q analogue idebenone for MELAS and LHON. Greater experience has accumulated with multi-center trials of coenzyme Q(10) treatment to prevent the progression of Parkinson disease. Although initial smaller trials indicated a benefit, this has not yet been confirmed in subsequent trials with higher doses; a larger Phase III trial is now underway. Similarly, a series of trials of idebenone for Friedreich ataxia have shown some benefit in slowing the progression of cardiomyopathy, and controlled clinical trials are now underway to determine if there is significant neurological protection. Uncontrolled trials of exercise showed an increase of exercise tolerance in patients with disorders of mitochondrial DNA, but did not selectively increase the percentage of normal mtDNA; a larger partially controlled trial is now underway to evaluate this possible benefit. In summary, none of the controlled trials so far has conclusively shown a benefit of treatment with the agents tested, but some promising therapies are currently being evaluated in a controlled manner. These experiences underscore the importance of controlled clinical trials for evaluation of benefits and risks of recommended therapies. Application of such clinical trials to future more effective therapies for mitochondrial disorders will require multi-center collaboration, organization, leadership, and financial and advocacy support.

Topics: Arginine; Clinical Trials as Topic; Dichloroacetic Acid; Humans; Mitochondrial Diseases; Randomized Controlled Trials as Topic; Treatment Outcome; Ubiquinone

Idebenone is a synthetic short chain benzoquinone that acts as an electron carrier in the mitochondrial electron transport chain, thereby, facilitating the production of ATP. In addition, idebenone is an antioxidant and can inhibit lipid peroxidation and may protect cell membranes and mitochondria from oxidative damage. High dose idebenone (Catena(®)) is approved in Canada for the symptomatic treatment of Friedreich's ataxia and is currently under clinical investigation for use in a number of mitochondrial and neuromuscular diseases.. This review summarizes the pharmacology, pharmacokinetic and clinical efficacy/safety data of idebenone and its metabolites and provides an update of the clinical trials completed and in progress.. Following oral administration, idebenone is rapidly metabolized via oxidative shortening by a number CYP isoenzymes (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4) to yield QS10, QS8, QS6 and QS4. Idebenone and these metabolites concomitantly undergo conjugation via glucuronidation and sulfatation to yield conjugated moieties represented as idebenone-C, QS10-C, QS8-C, QS6-C and QS4-C. Previous reports in the literature were only able to quantify plasma concentrations of idebenone measured together with its conjugates. More recently, highly sensitive and specific liquid chromatography method with tandem mass spectrometric methods have been developed, allowing the quantification of the parent molecule idebenone and its main metabolite QS10, separately.. After absorption, idebenone is rapidly metabolized by first pass metabolism and shows dose-proportional pharmacokinetics in healthy subjects in daily doses up to 2250 mg. The recent development of advanced analytical techniques allows the detection of idebenone and unconjugated metabolites in plasma and consequently opens the possibility for evaluation of pharmacokinetic/pharmacodynamic relationships which will be helpful to further understand the metabolism and therapeutic potential of idebenone. In clinical studies, idebenone was safe and well tolerated at doses up to 2250 mg/day.

Topics: Administration, Oral; Animals; Antioxidants; Chromatography, Liquid; Cytochrome P-450 Enzyme System; Dose-Response Relationship, Drug; Friedreich Ataxia; Humans; Tandem Mass Spectrometry; Ubiquinone

This paper reviews the history and pre-clinical development of idebenone and summarises the results of clinical studies, published from 1999 to 2008, on the use of idebenone in the treatment of patients with Friedreich ataxia (FRDA). As a benzoquinone that can undergo reversible redox reactions, idebenone influences the electron balance in mitochondria. In vitro studies have shown that it acts both as an anti-oxidant, preventing damage to the mitochondrial membrane, and, more importantly, as an electron carrier, supporting mitochondrial function and adenosine triphosphate (ATP) production. In clinical studies, idebenone has been well tolerated by patients with various pathological conditions. The most common adverse events have been gastrointestinal effects of mild to moderate severity. No neurotoxic or adverse cardiac reactions have been reported in pre-clinical or clinical studies. The good safety profile of idebenone is supported by large clinical trials in Alzheimer's disease and by post-marketing surveillance. Phase 1 studies demonstrated the safety and tolerability of idebenone at relatively high doses (up to 60 mg/kg/day). Results from 11 clinical studies (randomised, controlled, and open-label trials), involving a total of about 200 patients, provide evidence of improvement in both cardiac hypertrophy and neurological symptoms among patients with FRDA treated with idebenone.

Topics: Animals; Antioxidants; Cardiomyopathy, Hypertrophic; Friedreich Ataxia; Humans; Nervous System Diseases; Ubiquinone

Several reports in the literature describe the effects of low-dose (5 mg/kg/day) idebenone in significantly reducing cardiac hypertrophy in patients with Friedreich ataxia. However, the effects of idebenone on neurological function have not been reliably determined in these studies; when neurological parameters were reported, results were often inconclusive, usually because of subject heterogeneity and lack of adequate statistical power. In two of these studies, some patients showed beneficial effects of idebenone on their cardiomyopathy only when the dose was increased, prompting the systematic investigation of higher doses of idebenone. Following a phase 1 dose escalation study, a phase 2 tolerability and efficacy trial with low, intermediate, and high doses of idebenone was conducted. The results suggested that treatment with intermediate- and high-dose idebenone had beneficial effects on neurological symptoms. On the basis of these results, two phase 3 trials have been initiated, one in the United States with young ambulatory patients and one in Europe without limits on age and disease severity.

Topics: Antioxidants; Cardiomyopathies; Clinical Protocols; Clinical Trials as Topic; Dose-Response Relationship, Drug; Friedreich Ataxia; Humans; Nervous System Diseases; Ubiquinone

Friedreich ataxia (FA) is a progressive genetic neurological disorder associated with degeneration of the dorsal columns, spinocerebellar tracts and other regions of the nervous system. The disorder results from mutations in the gene referred to as FXN. Almost all mutations are expansions of an intronic GAA repeat in this gene, which gives rise to decreased transcription of the gene product (called frataxin). Following these discoveries, drug discovery has moved at a rapid pace. Therapeutic trials in the next 5 years are expected to address amelioration of the effects of frataxin deficiency and methods for increasing frataxin expression. These therapies are directed at all levels of biochemical dysfunction in FA. Agents such as idebenone potentially improve mitochondrial function and decrease production of reactive oxygen species. Idebenone is presently in a phase III trial in the US and in Europe, with the primary outcome measure being neurological function. Deferiprone, an atypical iron chelator, may decrease build-up of toxic iron in the mitochondria in patients. It has entered a phase II trial in Europe, Australia and Canada directed toward improvement of neurological abilities. Finally, targeted histone deacetylase (HDAC) inhibitors and erythropoietin increase levels of frataxin when used in vitro, suggesting that they may provide methods for increasing frataxin levels in patients. Erythropoietin has been tested in a small phase II trial in Austria, while HDAC inhibitors are still at a preclinical stage. Symptomatic therapies are also in use for specific symptoms such as spasticity (baclofen). Thus, there is substantial optimism for development of new therapies for FA in the near future, and we suggest that one or several may be available over the next few years. However, continued development of new therapies will require creation of new, more sensitive measures for neurological dysfunction in FA, and clinically relevant measures of cardiac dysfunction.

Topics: Animals; Antioxidants; Deferiprone; Enzyme Inhibitors; Erythropoietin; Friedreich Ataxia; Histone Deacetylase Inhibitors; Humans; Iron Chelating Agents; Organophosphorus Compounds; Pyridones; Recombinant Proteins; Ubiquinone

Friedreich ataxia is a rare inherited, autosomal recessive, neurological disorder characterised initially by unsteadiness in standing and walking, slowly progressing to wheelchair dependency usually in the late teens or early twenties. It is associated with slurred speech, scoliosis, pes cavus and heart abnormalities which may cause premature death in 60 to 80% of people. There is no easily defined clinical or biochemical marker and no known treatment.. To examine the efficacy of antioxidants and other pharmacological treatments for Friedreich ataxia.. We searched The Cochrane Neuromuscular Disease Group Trials Specialized Register (17 December 2008), The Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2008) MEDLINE (January 1950 to December 2008), EMBASE (January 1980 to December 2008) and other sources.. All randomised controlled trials (RCTs) or quasi-randomised trials which examined drug treatment in people with genetically confirmed Friedreich ataxia were examined. The primary outcome was change in ataxia rating scale as measured by the International Co-operative Ataxia Rating Scale (ICARS) after 12 months. Secondary outcomes included change in left ventricular heart mass as measured by magnetic resonance imaging or echocardiography.. Three authors selected the trials and two authors extracted data. We obtained missing data from the one RCT that met our inclusion criteria.. Over 10 studies used idebenone in the treatment of Friedreich ataxia but only one small RCT, with 29 participants using the synthetic antioxidant, idebenone 5 mg/kg, fulfilled the selection criteria for this review. Another RCT was of insufficient duration and the other studies were open clinical trials. In the included study, the primary outcome, change in ICARS scale, did not reveal any significant differences with idebenone treatment. The secondary outcome, change in left ventricular heart mass index as measured by magnetic resonance spectroscopy was not carried out. The second secondary outcome, change in left ventricular mass, as measured by echocardiography, did improve significantly (P = 0.007). There were no adverse events. A larger RCT using idebenone is in progress, of which the primary outcome is change in the ICARS scale. However, the results are not yet available.. No RCT using idebenone or any other pharmacological treatment has shown significant benefit on neurological symptoms associated with Friedreich ataxia. Idebenone has shown a positive effect on left ventricular heart mass but no research on clinical relevance of this change has been done.

Topics: Antioxidants; Friedreich Ataxia; Humans; Ubiquinone

This article provides an overview of recent advances in the field of inherited ataxias. In the past few years, new causative mutations that broaden the diagnostic spectrum of ataxias have been described. In addition, important advances have unveiled the molecular pathology of these disorders, resulting in a classification based on the pathogenetic pathways rather than clinical or genetic features. As concepts of treatment principles emerge, debate continues as to whether such concepts might be applicable to more than one genetically defined disorder or whether each ataxia disorder requires its own unique therapeutic approach. New clinical assessment instruments have been developed that will facilitate future interventional trials. A recent phase 2 clinical trial suggested a positive effect of high-dose idebenone in Friedreich's ataxia, raising hopes that a treatment option will soon be available for this disorder.

Topics: Antioxidants; Ataxia; Humans; Ubiquinone

Friedreich's ataxia is an autosomal recessive neurodegenerative disease where impaired mitochondrial function and excessive production of free radicals play a central pathogenetic role. Idebenone, a synthetic analogue of coenzyme Q, is a powerful antioxidant that was first administrated to Friedreich's ataxia patients less than 10 years ago.. The aim of this study was to evaluate the efficacy of idebenone administration and define the optimal dosage.. A critical evaluation of all open and double-blinded idebenone trials in Friedreich's ataxia patients was undertaken.. Idebenone is well tolerated in paediatric and adult patients. Most trials demonstrated a positive effect on cardiac hypertrophy. The neurological function is in general not modified in adult patients, but a dose-dependent effect was demonstrated in young Friedreich's ataxia patients. Further double-blinded high-dose trials should evaluate idebenone in Friedreich's ataxia early in the disease course.

Topics: Antioxidants; Clinical Trials as Topic; Dose-Response Relationship, Drug; Friedreich Ataxia; Humans; Magnetic Resonance Angiography; Ubiquinone

Since the term "cosmeceutical" was coined over 2 decades ago, the number of products in this category that claim to combat dermal aging has grown dramatically. Topical retinoids remain the mainstay for treating photoaging given their proven efficacy in both clinical and histologic outcomes. In addition to retinoids, many other cosmeceutical agents are now available. The proliferation of products can cause confusion among consumers, who often ask their dermatologist for advice as to which antiaging products they should choose. Ideally, the antiaging claims of cosmeceutical formulations and their components should be demonstrated in controlled clinical trials. In order to provide appropriate recommendations to their patients, dermatologists must become familiar with the available data on currently marketed products and gain experience with antiaging regimens. This review discusses the efficacy of a number of currently marketed drug products with proven photoaging benefits and cosmeceutical products that claim similar benefits. Among the agents discussed are single-entity and combination products containing hydroquinones, retinoids, topical antioxidants, and minerals.

Topics: Administration, Topical; Antioxidants; Benzoquinones; Cosmetics; Dermatologic Agents; Drug Combinations; Humans; Hydroquinones; Retinoids; Skin Aging; Tretinoin; Ubiquinone

Since the identification of the genetic mutation causing Friedreich's ataxia (FRDA) our understanding of the mechanisms underlying disease pathogenesis have improved markedly. The genetic abnormality results in the deficiency of frataxin, a protein targeted to the mitochondrion. There is extensive evidence that mitochondrial respiratory chain dysfunction, oxidative damage and iron accumulation play significant roles in the disease mechanism. There remains considerable debate as to the normal function of frataxin, but it is likely to be involved in mitochondrial iron handling, antioxidant regulation, and/or iron sulphur centre regulation. Therapeutic avenues for patients with FRDA are beginning to be explored in particular targeting antioxidant protection, enhancement of mitochondrial oxidative phosphorylation, iron chelation and more recently increasing FRDA transcription. The use of quinone therapy has been the most extensively studied to date with clear benefits demonstrated using evaluations of both disease biomarkers and clinical symptoms, and this is the topic that will be covered in this review.

Topics: Animals; Ataxia; Benzoquinones; Coenzymes; Disease Models, Animal; Friedreich Ataxia; Humans; Iron; Mutation; Neurodegenerative Diseases; Oxidative Stress; Oxygen; Quinones; Time Factors; Ubiquinone; Vitamin E

Topics: Antioxidants; Benzoquinones; Humans; Nervous System Diseases; Neurology; Treatment Outcome; Ubiquinone

Friedreich's ataxia (FRDA) is an autosomal recessive neurodegenerative disease causing limb and gait ataxia and cardiomyopathy. The disease gene encodes a mitochondrial protein of unknown function, frataxin. The loss of functional frataxin is caused by a large GAA trinucleotide expansion in the first intron of the gene, thus impairing gene transcription. The lack of frataxin appears to result primarily in disabled recruitment of early antioxidant defenses, resulting in oxidative insult to the highly sensitive iron-sulfur proteins aconitase and three mitochondrial respiratory chain complexes (I-III). Accordingly, antioxidant-based therapy appears promising in counteracting the course of the disease.

Topics: Animals; Antioxidants; Benzoquinones; Carrier Proteins; Frataxin; Friedreich Ataxia; Humans; Iron; Iron-Binding Proteins; Mice; Ubiquinone

Topics: Alzheimer Disease; Animals; Antioxidants; Benzoquinones; Cerebrovascular Disorders; Friedreich Ataxia; Humans; Liver Diseases; Ubiquinone

Astrocytes, the most abundant glial cell type in the brain, are considered to have physiological and pathological roles in neuronal activities. We found that reperfusion of cultured astrocytes after Ca2+ depletion causes Ca2+ overload followed by delayed cell death and the Na(+)-Ca2+ exchanger in the reverse mode is responsible for this Ca(2+)-mediated cell injury (Ca2+ paradox injury). The Ca2+ paradox injury of cultured astrocytes is considered to be an in vitro model of ischemia/reperfusion injury, since a similar paradoxical change in extracellular Ca2+ concentration is reported in ischemic brain tissue. This review summarizes the mechanisms underlying the Ca(2+)-mediated injury of astrocytes and the protective effects of drugs against Ca2+ reperfusion injury. This study shows that Ca2+ reperfusion injury of astrocytes is accompanied by apoptosis as evidenced by DNA fragmentation and nuclear condensation. Calpain, reactive oxygen species, calcineurin, caspase-3, and NF-kappa B are involved in Ca2+ reperfusion-induced delayed apoptosis of astrocytes. Several drugs including CV-2619, T-588 and ibudilast protect astrocytes against the delayed apoptosis. CV-2619 prevents astrocytes from the delayed apoptosis by production of nerve growth factor, resulting in an activation of mitogen-activated protein (MAP)/extracellular signal-regulated kinase (ERK) and phosphatidylinositol-3 (PI3) kinase signal pathways. The protective effect of T-588 is mainly mediated by an activation of MAP/ERK signal cascade. Moreover, ibudilast prevents the Ca2+ reperfusion-induced delayed apoptosis of astrocytes via cyclic GMP signaling pathway. Further studies in this system will contribute to the development of new drugs that attenuate ischemia/reperfusion injury via modulation of astrocytes.

Topics: Animals; Apoptosis; Astrocytes; Benzoquinones; Calcium; Cells, Cultured; Diethylamines; Humans; MAP Kinase Signaling System; Mitogen-Activated Protein Kinase Kinases; Reperfusion Injury; Sodium-Calcium Exchanger; Thiophenes; Ubiquinone

Topics: Aconitate Hydratase; Antioxidants; Benzoquinones; Frataxin; Friedreich Ataxia; Humans; Iron; Iron-Binding Proteins; Mitochondria; Phosphotransferases (Alcohol Group Acceptor); Ubiquinone

Alzheimer's disease is one of the most challenging brain disorders and has profound medical and social consequences. It affects approximately 15 million persons worldwide, and many more family members and care givers are touched by the disease. The initiating molecular event(s) is not known, and its pathophysiology is highly complex. However, free radical injury appears to be a fundamental process contributing to the neuronal death seen in the disorder, and this hypothesis is supported by many (although not all) studies using surrogate markers of oxidative damage. In vitro and animal studies suggest that various compounds with antioxidant ability can attenuate the oxidative stress induced by beta-amyloid. Recently, clinical trials have demonstrated potential benefits from treatment with the antioxidants, vitamin E, selegiline, extract of Gingko biloba, and idebenone. Further studies are warranted to confirm these findings and explore the optimum timing and antioxidant combination of such treatments in this therapeutically frustrating disease.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Animals, Genetically Modified; Antioxidants; Ascorbic Acid; Benzoquinones; Central Nervous System; Central Nervous System Diseases; Clinical Trials as Topic; Drug Therapy, Combination; Free Radicals; Ginkgo biloba; Humans; Lipid Peroxidation; Neuroprotective Agents; Oxidation-Reduction; Phytotherapy; Plants, Medicinal; Selegiline; Ubiquinone; Vitamin E

Incubation of cultured astrocytes in Ca(2+)-containing medium after exposure to Ca(2+)-free medium causes Ca2+ influx followed by delayed cell death. Here, we summarize the mechanisms underlying the Ca(2+)-mediated injury of cultured astrocytes and the protective effects of drugs against Ca(2+)-reperfusion injury. Our results show that Ca(2+)-reperfusion injury of astrocytes appears to be mediated by apoptosis as evidenced by DNA fragmentation and nuclear condensation. Calpain, reactive oxygen species (ROS) production, calcineurin, caspase-3, and NF-kappa B activation are involved in Ca(2+)-reperfusion injury. Several drugs including T-588 and idebenone protect astrocytes against Ca(2+)-reperfusion injury. The protective effect of idebenone is mediated by nerve growth factor production, whereas that of T-588 is mediated mainly by the mitogen-activated protein/extracellular signal-regulated kinase signal cascade.

Topics: Animals; Apoptosis; Astrocytes; Benzoquinones; Calcium; Calpain; Cell Death; Cells, Cultured; Humans; Reperfusion Injury; Ubiquinone

The degeneration of cholinergic neurons may be responsible for cognitive impairment in patients with Alzheimer's disease (AD). Since nerve growth factor (NGF) plays an important role in the survival and maintenance of cholinergic neurons in the central nervous system, this factor may have some beneficial effects on the cognitive impairment observed in patients with AD. However, since NGF does not cross the blood-brain barrier and is easily metabolized when administered peripherally, it can only be used when directly injected into the brain. In this review, we show that repeated oral administration of the NGF synthesis stimulators, idebenone and propentofylline, partially restored the age-associated decrease of NGF in the frontal and parietal cortices. Furthermore, this treatment attenuated the impairment of performance in the water maze, passive avoidance, and habituation tasks in rats with bilateral forebrain lesions, and in rats which had received continuous infusion of anti-NGF antibody into the septum. The behavioral improvement induced by idebenone and propentofylline was accompanied by recovery of both the reduced activity of choline acetyltransferase and the changes in [3H]QNB binding. These results suggest that the use of NGF synthesis stimulators may provide a novel therapeutic approach to cholinergic dysfunction.

Topics: Alzheimer Disease; Animals; Benzoquinones; Humans; Nerve Growth Factors; Nootropic Agents; Rats; Ubiquinone; Xanthines

Idebenone is a benzoquinone compound which has been investigated in elderly patients with dementia. Its precise mechanism(s) of action remains unknown, but in vitro and in vivo studies suggest the drug may diminish nerve cell damage due to ischaemia, correct neurotransmitter defects and/or cerebral metabolism and facilitate memory and learning. In the small number of studies available for evaluation, idebenone was generally superior to placebo and comparable with bifemelane, oxiracetam and nebracetam on the basis of a number of objective and subjective tests and rating scales in patients with mild to moderate cognitive decline. Clinical trial results indicate that patients with mild dementia seem more likely to respond than those with greater functional decline. The degree of benefit conferred by idebenone is often difficult to determine, but in those who respond, improvement is generally mild to moderate. Therapy with idebenone appears well tolerated for up to 2 years, and no changes in vital signs or laboratory values have been seen in clinical trials. In view of the lack of a proven agent to limit or halt the progression of dementia in the elderly, idebenone may warrant consideration in patients with mild cognitive dysfunction on the basis of preliminary evidence of predominantly mild improvement of functional status in some patients and good tolerability. However, further well designed studies, including comparisons with newer and commonly used agents, such as tacrine, are required to better define the role of idebenone in this complex area of treatment.

Topics: Administration, Oral; Aging; Benzoquinones; Cognition Disorders; Drug Administration Schedule; Humans; Intestinal Absorption; Memory; Psychotropic Drugs; Pyrrolidines; Randomized Controlled Trials as Topic; Tissue Distribution; Ubiquinone

Topics: Aged; Antidepressive Agents; Benzoquinones; Brain; Cerebrovascular Circulation; Cerebrovascular Disorders; Dementia; Humans; Middle Aged; Morpholines; Ubiquinone; Vasodilator Agents

Syntheses of some metabolites of ubiquinone and of related compounds are described. Idebenone (QSA-10), a methyl-dimethoxy-benzoquinone bearing an omega-hydroxydecyl side chain in 3-position, restored the oxidation of succinate and of NADH in ubiquinone-depleted mitochondrial preparations and showed a stabilizing effect on lysosomal membranes and an inhibitory effect on cAMP-phosphodiesterase. It inhibited lipid peroxidation in canine brain mitochondria and in microsomes from canine brain and rat liver. Administered orally to rats, it increased the respiratory control index for glutamate and succinate oxidation but had no effect on the ADP/O2 ratio. Pharmacological effects of idebenon are also briefly discussed.

Topics: Animals; Benzoquinones; Brain; Lipid Peroxidation; Microsomes; Mitochondria; NAD; Quinones; Ubiquinone

The effects of idebenone on the swelling of rat brain mitochondria were studied. When FeCl3 was added to a mitochondrial suspension, a pronounced mitochondrial swelling occurred accompanied by the production of lipid peroxide; the two phenomena were closely correlated (r = 0.96, p less than 0.01). Idebenone inhibited the mitochondrial swelling and lipid peroxidation in a concentration-dependent manner; the concentration giving 50% inhibition was 37 microM for swelling and 53 microM for lipid peroxidation. Metabolites of idebenone also inhibited the lipid peroxidation. These results suggest that idebenone stabilizes the mitochondrial membrane by inhibiting lipid peroxidation in brain mitochondria.

Topics: Animals; Benzoquinones; Brain; Dose-Response Relationship, Drug; Lipid Peroxidation; Male; Mitochondrial Swelling; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

The purpose of the study was to present results from a national Dutch cohort of patients with Leber's Hereditary Optic Neuropathy (LHON) treated with idebenone.. The multicentre, open-label, retrospective evaluation of the long-term outcome of idebenone treatment of Dutch LHON patients on visual function and on thickness of the retinal ganglion cell layer. Patients included in the analysis had a confirmed mutation in their mitochondrial DNA encoding either of the seven subunits of complex I, had a reported loss of vision in at least one eye and had a follow-up of more than 6 months after their treatment was started. Control visits involved routine clinical examinations of visual function and retinal structure at (1) the start of treatment, (2) nadir (time of lowest visual acuity), (3) the time of recovery (if any), (4) the time of termination of treatment and (5) more than 6 months after termination of the treatment.. Data from 72 patients were analysed. Treatment duration was 23.8 ± 14.4 (mean ± SD) months. A positive response, that is either a clinically relevant recovery (CRR) or a clinically relevant stabilization (CRS), occurred in 53% and 11% of the patients, respectively. The magnitude of CRR was 0.41 ± 1.54 logMAR. CRR of visual acuity is associated with recovery of colour discrimination. The thickness of both the ganglion cell complex (GCC) and the retinal nerve fibre layer (RNFL) is irreversibly reduced.. Our results confirm that idebenone may help to restore or maintain visual function. Whether this effect will persist is still unknown. Thinning of retinal neural tissue appears to be permanent.

Topics: Antioxidants; Cohort Studies; Humans; Netherlands; Optic Atrophy, Hereditary, Leber; Retrospective Studies; Treatment Outcome; Ubiquinone

Decline in respiratory function in patients with DMD starts during early teenage years and leads to early morbidity and mortality. Published evidence of efficacy for idebenone on respiratory function outcomes is currently limited to 12 months of follow-up time. Here we report data collected as retrospective cohort study (SYROS) from 18 DMD patients not using glucocorticoids who were treated with idebenone (900 mg/day) under Expanded Access Programs (EAPs). The objective was to assess the long-term respiratory function evolution for periods On-Idebenone compared to periods Off-Idebenone in the same patients. The mean idebenone exposure in the EAPs was 4.2 (range 2.4-6.1) years. The primary endpoint was the annual change in forced vital capacity percent of predicted (FVC%p) compared between Off-Idebenone and On-Idebenone periods. The annual rate of decline in FVC%p was reduced by approximately 50% from -7.4% (95% CI: -9.1, -5.8) for the Off-Idebenone periods to -3.8% (95% CI: -4.8, -2.8) for the On-Idebenone periods (N = 11). Similarly, annual change in peak expiratory flow percent of predicted (PEF%p) was -5.9% (95% CI: -8.0, -3.9) for the Off-Idebenone periods (N = 9) and reduced to -1.9% (95% CI: -3.2, -0.7) for the On-Idebenone periods during the EAPs. The reduced rates of decline in FVC%p and PEF%p were maintained for several years with possible beneficial effects on the rate of bronchopulmonary adverse events, time to 10% decline in FVC%p and risk of hospitalization due to respiratory cause. These long-term data provide Class IV evidence to further support the disease modifying treatment effect of idebenone previously observed in randomized, controlled trials.

Topics: Adolescent; Adult; Antioxidants; Child; Follow-Up Studies; Humans; Male; Muscular Dystrophy, Duchenne; Outcome Assessment, Health Care; Respiration Disorders; Respiratory Function Tests; Retrospective Studies; Ubiquinone; Vital Capacity; Young Adult

To determinate the clinical effect of butyphthalide combined with idebenone in the treatment of vascular dementia (VD) and the influence on inflammatory cytokines and vascular endothelial functions.. Clinical comparative study.. Department of Neurology, Baoding First Central Hospital, from June 2017 to June 2018.. Eighty-eight VD patients were divided into observation group (44 cases) and control group (44 cases) at random. Idebenone was given to the control group, and butyphthalide combined with idebenone was given to the observation group for 12 weeks. C-reactive protein (CRP), tumor necrosis factor α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) were detected before and after the treatment to evaluate the level of serum inflammatory factors. Peripheral blood endothelial microparticles (EMPs), endothelin (ET-1), and vascular endothelial growth factor (VEGF) were detected to evaluate vascular endothelial functions. Mini-mental state examination (MMSE), clinical dementia scale (CDR), and ability of daily life (ADL), were used to evaluate cognitive function, dementia degree, and self-care ability in daily life. The occurrences of adverse reactions were recorded.. Before the treatment, the comparison differences in the indexes of both groups had no statistical significance (p>0.05). After the treatment, the scores of CD62E+, VEGF, and MMSE of observation group rose obviously, compared with those before the treatment, and were significantly higher than those of control group (p <0.05). After the treatment, the scores of IL-6, CRP, TNF-α, IL-1β, CD31+, CDl44+, ET-1, CDR and ADL of observation group significantly lowered, compared with those before the treatment, and were significantly lower than those of control group (p <0.05). The differences in the adverse reactions of both groups had no statistical significance (p >0.05).. Butyphthalide combined with idebenone can effectively reduce serum inflammatory factor level of VD patients, regulate vascular endothelial functions, relieve dementia degree, and improve cognitive function and daily activity ability.

Topics: Activities of Daily Living; Aged; Antioxidants; Benzofurans; C-Reactive Protein; Cytokines; Dementia, Vascular; Drug Therapy, Combination; Endothelin-1; Female; Humans; Male; Middle Aged; Neuroprotective Agents; Ubiquinone; Vascular Endothelial Growth Factor A

Multiple sclerosis (MS) is a chronic, immune-mediated neurodegenerative disorder of the central nervous system (CNS). While current MS therapies target the inflammatory processes, no treatment explicitly targets mitochondrial dysfunction and resulting axonal loss. Therefore, the aim of this study was to determine whether idebenone inhibits mitochondrial dysfunction and accumulation of disability in primary progressive MS (PPMS) and to enhance understanding of pathogenic mechanisms of PPMS progression using cerebrospinal fluid (CSF) biomarkers.. The double-blind, placebo-controlled Phase I/II clinical trial of Idebenone in patients with Primary Progressive MS (IPPoMS; NCT00950248) was an adaptively designed, baseline-versus-treatment, placebo-controlled, CSF-biomarker-supported trial. Based on interim analysis of the 1-year pre-treatment data, change in the area under the curve of Combinatorial Weight-Adjusted Disability Score (CombiWISE) became the primary outcome, with >80% power to detect ≥40% efficacy with 28 patients/arm treated for 2 years in baseline versus treatment paradigm. Changes in traditional disability scales and in brain ventricular volume were secondary outcomes. Exploratory outcomes included CSF biomarkers of mitochondrial dysfunction (Growth/differentiation factor 15 [GDF15] and lactate), axonal damage (neurofilament light chain [NFL]), innate immunity (sCD14), blood brain barrier leakage (albumin quotient) and retinal nerve fiber layer thinning.. Idebenone was well tolerated but did not inhibit disability progression or CNS tissue destruction. Concentrations of GDF15, secreted predominantly by astrocytes and choroid plexus epithelium in vitro, increased after exposure to mitochondrial toxin rotenone, validating the ability of this biomarker to measure intrathecal mitochondrial damage. CSF GDF15 levels correlated strongly with age and MS patients had CSF levels of GDF15 significantly above age-adjusted healthy volunteers, with highest levels measured in PPMS. Idebenone did not change CSF GDF15 levels.. Mitochondrial dysfunction exceeding normal aging reflected by age-adjusted CSF GDF15 is present in the majority of PPMS patients, but it is not inhibited by idebenone.

Topics: Axons; Biomarkers; Disease Progression; Double-Blind Method; Humans; Multiple Sclerosis; Multiple Sclerosis, Chronic Progressive; Ubiquinone

Leber hereditary optic neuropathy (LHON) leads to bilateral central vision loss. In a clinical trial setting, idebenone has been shown to be safe and to provide a trend toward improved visual acuity, but long-term evidence of effectiveness in real-world clinical practice is sparse.. Open-label, multicenter, retrospective, noncontrolled analysis of long-term visual acuity and safety in 111 LHON patients treated with idebenone (900 mg/day) in an expanded access program. Eligible patients had a confirmed mitochondrial DNA mutation and had experienced the onset of symptoms (most recent eye) within 1 year before enrollment. Data on visual acuity and adverse events were collected as per normal clinical practice. Efficacy was assessed as the proportion of patients with either a clinically relevant recovery (CRR) or a clinically relevant stabilization (CRS) of visual acuity. In the case of CRR, time to and magnitude of recovery over the course of time were also assessed.. At time of analysis, 87 patients had provided longitudinal efficacy data. Average treatment duration was 25.6 months. CRR was observed in 46.0% of patients. Analysis of treatment effect by duration showed that the proportion of patients with recovery and the magnitude of recovery increased with treatment duration. Average gain in best-corrected visual acuity for responders was 0.72 logarithm of the minimal angle of resolution (logMAR), equivalent to more than 7 lines on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Furthermore, 50% of patients who had a visual acuity below 1.0 logMAR in at least one eye at initiation of treatment successfully maintained their vision below this threshold by last observation. Idebenone was well tolerated, with most adverse events classified as minor.. These data demonstrate the benefit of idebenone treatment in recovering lost vision and maintaining good residual vision in a real-world setting. Together, these findings indicate that idebenone treatment should be initiated early and be maintained more than 24 months to maximize efficacy. Safety results were consistent with the known safety profile of idebenone.

Topics: Adolescent; Adult; Aged; Antioxidants; Child; Female; Follow-Up Studies; Humans; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Retrospective Studies; Time Factors; Treatment Outcome; Ubiquinone; Visual Acuity; Young Adult

Friedreich's ataxia is the most common inherited ataxia, and pathogenesis is known to involve mitochondrial oxidative stress. Idebenone is a potent antioxidant which has already been evaluated in several clinical trials in FRDA, with reports of symptomatic benefit but inconclusive objective results. Following patient consultation on design, we have completed a treatment-withdrawal study to establish whether patients could correctly determine their treatment allocation to placebo or idebenone. Our aim was to capture subjective experiences of symptoms such as fatigue, which can be difficult to measure with questionnaires or semi-quantitative scales, particularly in chronic, slowly progressive conditions.. Patients taking idebenone for at least 12 months as part of the open-label MICONOS Extension Study were randomized to receive either placebo or idebenone continuation for 2-month treatment cycles. The primary endpoint was patient assessment of treatment assignment.. A total of 29 patients were randomized, forming the idebenone group (n = 16) and the placebo group (n = 13). No significant differences were detected between the idebenone and placebo groups on assessment of treatment assignment or early study withdrawal. A small but significant difference in ataxia rating scale scores was detected between treatment groups when considering ambulatory patients only.. This study provides no data to suggest that FRDA patients could correctly determine their treatment assignment over a 2-month period. We hope that this study design will help inform future trials so that patients' experiences of symptoms are more reliably measured.

Topics: Adult; Antioxidants; Double-Blind Method; Female; Friedreich Ataxia; Humans; Male; Patient Reported Outcome Measures; Ubiquinone

Loss of pulmonary function is a main cause of early morbidity and mortality in patients with Duchenne muscular dystrophy (DMD). Standard of care guidelines recommend regular assessment of pulmonary function by hospital-based spirometry to detect onset and monitor progression of pulmonary function decline.. To assess the feasibility of home-based monitoring of pulmonary function by a hand-held device (HHD) in adolescent and adult patients with DMD over a period of 12 months.. In the phase III randomized placebo-controlled DELOS trial in 10-18 year old DMD patients, peak expiratory flow (PEF) measurements were collected weekly at home by the patient (assisted by parent/caregiver) using a peak flow meter HHD. Adherence to the use of the HHD was assessed and 12-month changes in PEF as percent of predicted (PEF% p) for the idebenone (N = 31) and the placebo treatment groups (N = 33) from HHD-derived data were compared to results from hospital-based spirometry.. A total of 2689 individual HHD assessments were analysed. Overall adherence to the use of the HHD over the course of the 12-month study duration was good (75.9%, SD 21.5%) and PEF% p data obtained at the same day by HHD and standard spirometry correlated well (Spearman's rho 0.80; p < 0.001). Several analysis methods of HHD-derived data for PEF% p consistently demonstrate that idebenone treatment slowed the decline in PEF% p compared to placebo, which supports the statistically significant difference in favour of idebenone for PEF% p measured by standard spirometry.. This study demonstrates that home-based monitoring of pulmonary function in adolescent patients with DMD using a HHD is feasible, provides reliable data compared to hospital-based spirometry and is therefore suitable for use in clinical practice and for clinical trials.

Topics: Adolescent; Antioxidants; Child; Humans; Male; Muscular Dystrophy, Duchenne; Peak Expiratory Flow Rate; Respiratory Function Tests; Self Care; Ubiquinone

Assessment of dynamic inspiratory function may provide valuable information about the degree and progression of pulmonary involvement in patients with Duchenne muscular dystrophy (DMD). The aims of this study were to characterize inspiratory function and to assess the efficacy of idebenone on this pulmonary function outcome in a large and well-characterized cohort of 10-18 year-old DMD patients not taking glucocorticoid steroids (GCs) enrolled in the phase 3 randomized controlled DELOS trial. We evaluated the effect of idebenone on the highest flow generated during an inspiratory FVC maneuver (maximum inspiratory flow; V'I,max(FVC)) and the ratio between the largest inspiratory flow during tidal breathing (tidal inspiratory flow; V'I,max(t)) and the V'I,max(FVC). The fraction of the maximum flow that is not used during tidal breathing has been termed inspiratory flow reserve (IFR). DMD patients in both treatment groups of DELOS (idebenone, n = 31; placebo: n = 33) had comparable and abnormally low V'I,max(FVC) at baseline. During the study period, V'I,max(FVC) further declined by -0.29 L/sec in patients on placebo (95%CI: -0.51, -0.08; P = 0.008 at week 52), whereas it remained stable in patients on idebenone (change from baseline to week 52: 0.01 L/sec; 95%CI: -0.22, 0.24; P = 0.950). The between-group difference favoring idebenone was 0.27 L/sec (P = 0.043) at week 26 and 0.30 L/sec (P = 0.061) at week 52. In addition, during the study period, IFR improved by 2.8% in patients receiving idebenone and worsened by -3.0% among patients on placebo (between-group difference 5.8% at week 52; P = 0.040). Although the clinical interpretation of these data is currently limited due to the scarcity of routine clinical practice experience with dynamic inspiratory function outcomes in DMD, these findings from a randomized controlled study nevertheless suggest that idebenone preserved inspiratory muscle function as assessed by V'I,max(FVC) and IFR in patients with DMD. Pediatr Pulmonol. 2017;52:508-515. © 2016 The Authors. Pediatric Pulmonology Published by Wiley Periodicals, Inc.

Topics: Adolescent; Antioxidants; Child; Female; Humans; Inspiratory Reserve Volume; Male; Muscular Dystrophy, Duchenne; Respiration; Respiratory Function Tests; Treatment Outcome; Ubiquinone

Friedreich ataxia is an inherited disorder characterized by degeneration of the peripheral and central nervous system and hypertrophic cardiomyopathy. Homozygous mutations in the frataxine (FXN) gene reduce expression of frataxin and cause accumulation of iron in the mitochondria. Deferiprone, an oral iron chelator, has been shown effective in cell and animal models of Friedreich ataxia. The results of a 6-month randomized, double blind placebo-controlled study suggested that deferiprone 20 mg/kg/day may reduce disease progression. The authors present their experience of 5 Friedreich ataxia patients treated with deferiprone (20 mg/kg/day), in addition to idebenone treatment, followed over a period of 10-24 months, under off-label authorization. The patients were monitored for laboratory parameters, cardiac assessment, neurological evaluations, and quality of life. The authors conclude that combined therapy of a low dose of deferiprone with idebenone is relatively safe, might improve neurological function, and seems to improve heart hypertrophy, warranting further studies.

Topics: Adolescent; Adult; Antioxidants; Deferiprone; Disease Progression; Double-Blind Method; Drug Therapy, Combination; Female; Follow-Up Studies; Friedreich Ataxia; Humans; Iron Chelating Agents; Male; Pyridones; Quality of Life; Treatment Outcome; Ubiquinone; Young Adult

In Duchenne muscular dystrophy (DMD), progressive loss of respiratory function leads to restrictive pulmonary disease and places patients at significant risk for severe respiratory complications. Of particular concern are ineffective cough, secretion retention and recurrent respiratory tract infections. In a Phase 3 randomized controlled study (DMD Long-term Idebenone Study, DELOS) in DMD patients 10-18 years of age and not taking concomitant glucocorticoid steroids, idebenone (900 mg/day) reduced significantly the loss of respiratory function over a 1-year study period. In a post-hoc analysis of DELOS we found that more patients in the placebo group compared to the idebenone group experienced bronchopulmonary adverse events (BAEs): placebo: 17 of 33 patients, 28 events; idebenone: 6 of 31 patients, 7 events. The hazard ratios (HR) calculated "by patient" (HR 0.33, p = 0.0187) and for "all BAEs" (HR 0.28, p = 0.0026) indicated a clear idebenone treatment effect. The overall duration of BAEs was 222 days (placebo) vs. 82 days (idebenone). In addition, there was also a difference in the use of systemic antibiotics utilized for the treatment of BAEs. In the placebo group, 13 patients (39.4%) reported 17 episodes of antibiotic use compared to 7 patients (22.6%) reporting 8 episodes of antibiotic use in the idebenone group. Furthermore, patients in the placebo group used systemic antibiotics for longer (105 days) compared to patients in the idebenone group (65 days). This post-hoc analysis of DELOS indicates that the protective effect of idebenone on respiratory function is associated with a reduced risk of bronchopulmonary complications and a reduced need for systemic antibiotics.

Topics: Adolescent; Anti-Bacterial Agents; Antioxidants; Child; Double-Blind Method; Humans; Incidence; Muscular Dystrophy, Duchenne; Proportional Hazards Models; Respiratory Function Tests; Respiratory System; Respiratory Tract Diseases; Treatment Outcome; Ubiquinone

Cardiorespiratory failure is the leading cause of death in Duchenne muscular dystrophy. Based on preclinical and phase 2 evidence, we assessed the efficacy and safety of idebenone in young patients with Duchenne muscular dystrophy who were not taking concomitant glucocorticoids.. In a multicentre phase 3 trial in Belgium, Germany, the Netherlands, Switzerland, France, Sweden, Austria, Italy, Spain, and the USA, patients (age 10-18 years old) with Duchenne muscular dystrophy were randomly assigned in a one-to-one ratio with a central interactive web response system with a permuted block design with four patients per block to receive idebenone (300 mg three times a day) or matching placebo orally for 52 weeks. Study personnel and patients were masked to treatment assignment. The primary endpoint was change in peak expiratory flow (PEF) as percentage predicted (PEF%p) from baseline to week 52, measured with spirometry. Analysis was by intention to treat (ITT) and a modified ITT (mITT), which was prospectively defined to exclude patients with at least 20% difference in the yearly change in PEF%p, measured with hospital-based and weekly home-based spirometry. This study is registered with ClinicalTrials.gov, number NCT01027884.. 31 patients in the idebenone group and 33 in the placebo group comprised the ITT population, and 30 and 27 comprised the mITT population. Idebenone significantly attenuated the fall in PEF%p from baseline to week 52 in the mITT (-3·05%p [95% CI -7·08 to 0·97], p=0·134, vs placebo -9·01%p [-13·18 to -4·84], p=0·0001; difference 5·96%p [0·16 to 11·76], p=0·044) and ITT populations (-2·57%p [-6·68 to 1·54], p=0·215, vs -8·84%p [-12·73 to -4·95], p<0·0001; difference 6·27%p [0·61 to 11·93], p=0·031). Idebenone also had a significant effect on PEF (L/min), weekly home-based PEF, FVC, and FEV1. The effect of idebenone on respiratory function outcomes was similar between patients with previous corticosteroid use and steroid-naive patients. Treatment with idebenone was safe and well tolerated with adverse event rates were similar in both groups. Nasopharyngitis and headache were the most common adverse events (idebenone, eight [25%] and six [19%] of 32 patients; placebo, nine [26%] and seven [21%] of 34 patients). Transient and mild diarrhoea was more common in the idebenone group than in the placebo group (eight [25%] vs four [12%] patients).. Idebenone reduced the loss of respiratory function and represents a new treatment option for patients with Duchenne muscular dystrophy.. Santhera Pharmaceuticals.

Topics: Adolescent; Antioxidants; Child; Double-Blind Method; Humans; Male; Muscular Dystrophy, Duchenne; Peak Expiratory Flow Rate; Respiration Disorders; Respiratory Function Tests; Respiratory Muscles; Treatment Outcome; Ubiquinone

The objective of the study was to test the efficacy, safety and tolerability of triple therapy with deferiprone, idebenone and riboflavin in Friedreich's ataxia (FRDA) patients in a clinical pilot study.. Patients included in this study were 10 males and three females, 14-61 years of age (average 30.2 ± 12.1), diagnosed with FRDA with normal ventricular function. Patients were treated with triple therapy with deferiprone at 5-25 mg/kg/day, idebenone at 10-20 mg/kg/day and riboflavin at 10-15 mg/kg/day for 15-45 months. The efficacy of this triple therapy was assessed by change from baseline on the scale for the assessment and rating of ataxia (SARA) and by the change from baseline in echocardiogram parameters.. Four patients discontinued due to adverse events (AEs) related with deferiprone. The annual worsening rate (AWR) was estimated in this series as 0.96 (CI 95%: 0.462-1.608) SARA score, whereas AWR for our FRDA cohort was estimated as 2.05 ± 1.23 SARA score. LVMI only decreased by 6.5 g/m(2) (6.2%) at the end of the first year of therapy. LVEF remained stable, except in case of three patients.. Our results seem to indicate some uncertain benefit on the neurological and heart functions of this triple therapy in FRDA.

Topics: Adolescent; Adult; Deferiprone; Female; Friedreich Ataxia; Humans; Male; Middle Aged; Pilot Projects; Pyridones; Riboflavin; Severity of Illness Index; Treatment Outcome; Ubiquinone; Ultrasonography; Ventricular Dysfunction, Left; Young Adult

Minimal objective evidence exists regarding management of Friedreich's ataxia (FRDA). Antioxidant and recombinant human erythropoietin therapies have been considered potential treatments to slow progression of FRDA in a small number of studies. The primary objective of the current study was to test the efficacy, safety, and tolerability of triple therapy-darbepoetin alfa, idebenone, and riboflavin-in FRDA in a clinical pilot study. Patients included in this study were nine females, 16 to 45 years of age (average 28 ± 8), diagnosed with FRDA with confirmed GAA repeat expansion mutations in the FXN gene and a GAA repeat ≥400 on the shorter allele. Patients had a baseline score between 8 and 28.5 (average 20.7 ± 8.3) on the scale for the assessment and rating of ataxia and 94.3 ± 27.2 g/m(2) in left ventricular mass index (LVMI). Patients had been treated with triple therapy with 150 μg darbepoetin alfa every 2 or 3 weeks, 10-20 mg/kg/day idebenone, and 10-15 mg/kg/day riboflavin for 32 ± 19.4 months (range of 8-56 months). Triple therapy was tolerated. Although not statistically significant, improvement of ataxia was observed during the first six 4-month periods of the study. Furthermore, a small decrease in disease progression during the first 2 years of treatment was observed. Long-term statistically nonsignificant improvement of LVMI and stability of the echocardiographic parameters could be considered. Triple therapy may slow disease progression of FRDA.

Topics: Adolescent; Adult; Antioxidants; Darbepoetin alfa; Drug Therapy, Combination; Erythropoietin; Female; Friedreich Ataxia; Hematinics; Humans; Male; Middle Aged; Pilot Projects; Riboflavin; Ubiquinone; Young Adult

In Duchenne muscular dystrophy (DMD) progressive weakness of respiratory muscles leads to a restrictive pulmonary syndrome that contributes to early morbidity and mortality. Currently no curative treatment exists for DMD. In a Phase II randomized placebo-controlled study (DELPHI) in 21 DMD boys at age 8-16 years, idebenone (450 mg/d) showed trends of efficacy for cardiac and respiratory endpoints. Since the DELPHI study population comprised both glucocorticoid-naïve subjects and glucocorticoid-users, we now report a post-hoc analysis investigating the effects of glucocorticoids and idebenone on markers of respiratory weakness, particularly peak expiratory flow (PEF) percent predicted (PEF%p). Baseline values of PEF%p correlated well with the percent predicted values for maximal inspiratory mouth pressure (MIP%p), forced vital capacity (FVC%p), and forced expired volume in 1 sec (FEV1%p). Baseline PEF%p and FVC%p were significantly higher in patients on concomitant glucocorticoids compared to glucocorticoid-naïve patients. In the latter subgroup, idebenone caused a 8.0 ± 12.1% improvement in PEF%p, whilst patients on placebo declined by -12.3 ± 17.9% (P < 0.05) in the course of the 12 month study. In patients receiving concomitant glucocorticoids, PEF%p remained stable (-0.4 ± 14.6%) in the idebenone group compared to a decline by -6.2 ± 12.4% (P = 0.24) in the placebo group. Idebenone showed a trend for efficacy on FVC%p only in glucocorticoid-naïve patients. Because of the study limitations, these data are exploratory and preclude any firm conclusions. In conclusion, PEF appears to be a sensitive respiratory function parameter that could be a valid and clinically relevant endpoint in intervention studies in DMD. In DELPHI the effect size of idebenone on PEF%p was significantly larger in steroid-naive patients, possibly indicating a maximum treatment effect reached by steroids or steroid-mediated suppression of idebenone's effects. The impact of standard care glucocorticoids on respiratory function will have to be considered in the planning of future interventional trials in DMD.

Topics: Adolescent; Antioxidants; Child; Double-Blind Method; Glucocorticoids; Humans; Lung; Male; Muscle Strength; Muscular Dystrophy, Duchenne; Respiration; Respiratory Function Tests; Respiratory Muscles; Ubiquinone; Vital Capacity

The authors investigated the correlation of protan and tritan color vision with disease characteristics in Leber hereditary optic neuropathy (LHON). The authors also characterized the therapeutic potential of idebenone in protecting patients from developing dyschromatopsia in LHON.. Color contrast data of 39 LHON patients participating in a randomized, double-blind placebo-controlled intervention study were evaluated. Patients reported disease onset <5 years before enrolment and were genetically confirmed. Protan and tritan color contrast sensitivity was measured using a computer graphics method in patients receiving idebenone (Catena; 900 mg/d; N = 28) or placebo (N = 11) for 6 months.. Mean age of patients was 28.1 years, 87.2% were men, 76.9% carried the m11778G>A mutation, and mean duration since onset was 2 years. Assessing protan and tritan color vision at baseline revealed a high degree of color confusion even in young patients (<25 years) and with a short history of disease (<1 year). Treatment with idebenone improved tritan color vision compared with placebo (P = 0.008 at week 24); a similar trend was seen for protan. The effect of idebenone was most prominent in patients with discordant visual acuity (interocular difference of logMAR >0.2). In this subgroup, the treatment effect at week 24 was 20.4% (P = 0.005) in favor of idebenone for the tritan color domain and 13.5% (P = 0.067) for the protan domain.. This study confirms that protan and tritan color confusion is an early symptom in LHON. Treatment with idebenone can protect from loss of color vision, particularly in patients who are at imminent risk of further vision loss.

Topics: Adolescent; Adult; Antioxidants; Color Perception; Double-Blind Method; Female; Humans; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Pigmentation Disorders; Skin Diseases, Genetic; Treatment Outcome; Ubiquinone

Topics: Adult; Child; Cohort Studies; Female; Follow-Up Studies; GTP Phosphohydrolases; Humans; Male; Middle Aged; Mutation; Optic Atrophy, Autosomal Dominant; Pilot Projects; Retrospective Studies; Treatment Outcome; Ubiquinone; Visual Acuity; Young Adult

Topics: Adolescent; Adult; Aged; Cohort Studies; Double-Blind Method; Female; Follow-Up Studies; Humans; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Time Factors; Treatment Outcome; Ubiquinone; Visual Acuity; Young Adult

The aim of this study was to investigate the efficacy of idebenone on neurological function as assessed by ICARS and FARS neurological rating scales in pediatric Friedreich's ataxia (FRDA) patients. Sixty-eight pediatric patients were enrolled in an open-label extension study (IONIA-E) where patients received idebenone (Catena(®), 150 mg film-coated tablets) at a weight-adjusted dose of 1,350/2,250 mg/day for 12 months after patients had completed a double-blind, randomized, placebo-controlled study (IONIA) receiving either idebenone at a weight-adjusted dose of 450/900 or 1,350/2,250 mg/day or placebo for 6 months. Changes in ICARS and FARS total scores and subscores were recorded for the 12-month IONIA-E study and for the 18-month combined IONIA and IONIA-E study period. Data analyzed by a mixed-model repeated-measures ANCOVA relative to baseline resulted in least square means for the change in ICARS for the IONIA-E study of +0.98 points (SEM 0.73; p = 0.180), indicating a trend for worsening. However, combined with the IONIA study the change was -1.03 ± 0.68 points (p = 0.132), indicating a trend for improvement in neurological function over the 18-month period. Importantly, patients who received idebenone 1,350/2,250 mg/day over this period significantly improved in neurological function (change in ICARS: -3.02 ± 1.22, p = 0.014). The improvement in neurological function over time was best seen when the posture and stance subscore was excluded from the analysis. Comparable data were obtained with the FARS. The findings of the open-label IONIA-E study combined with the double-blind IONIA study indicate that idebenone at a dose of 1,350/2,250 mg/day may offer a therapeutic benefit to pediatric FRDA patients by stabilizing the overall neurological function and improving fine motor skills and speech.

Topics: Adolescent; Antioxidants; Child; Dose-Response Relationship, Drug; Double-Blind Method; Female; Friedreich Ataxia; Humans; Male; Treatment Outcome; Ubiquinone

Friedreich ataxia is a rare disease caused by GAA-trinucleotide-repeat expansions in the frataxin gene, leading to marked reduction of qualitatively normal frataxin protein. Recently, human recombinant erythropoietin was reported to increase frataxin levels in patients with Friedreich ataxia.. We performed a 6-month, randomized placebo-controlled, double-blind, dose-response pilot trial to assess the safety and efficacy of erythropoietin in increasing frataxin levels. Sixteen adult patient with Friedreich ataxia were randomly assigned to erythropoietin (n = 11) or matching placebo (n = 5). All patients continued Idebenone treatment (5 mg/kg/day). Treatment consisted of a 6-month scaling-up phase, in which erythropoietin was administered intravenously at the following doses: 20,000 IU every 3 weeks, 40,000 IU every 3 weeks, and 40,000 IU every 2 weeks.. Erythropoietin treatment was safe and well tolerated, but did not result in any significant hematological, clinical, or biochemical effects in Friedreich ataxia patients.

Topics: Adult; Antioxidants; Dose-Response Relationship, Drug; Double-Blind Method; Erythropoietin; Female; Frataxin; Friedreich Ataxia; Humans; Iron-Binding Proteins; Male; Recombinant Proteins; Statistics, Nonparametric; Time Factors; Treatment Outcome; Ubiquinone; Young Adult

Friedreich ataxia (FRDA) is commonly associated with hypertrophic cardiomyopathy, but little is known about its frequency, severity, or treatment. In this 6-month randomized, double-blind, controlled study, we sought to determine whether idebenone improves cardiac measures in FRDA.. Seventy pediatric subjects were treated either with idebenone (450/900 mg/d or 1,350/2,250 mg/d) or with placebo. Electrocardiograms (ECGs) were assessed at each visit, and echocardiograms, at baseline and week 24.. We found ECG abnormalities in 90% of the subjects. On echocardiogram, 81.4% of the total cohort had left ventricular (LV) hypertrophy, as measured by increased LV mass index-Dubois, and the mean ejection fraction (EF) was 56.9%. In linear regression models, longer PR intervals at baseline were marginally associated with longer GAA repeat length (P = .011). Similarly, GAA repeat length did not clearly predict baseline EF (P = .086) and LV mass by M-mode (P = .045). Left ventricular mass index, posterior wall thickness, EF, and ECG parameters were not significantly improved by treatment with idebenone. Some changes in echocardiographic parameters during the treatment phase correlated with baseline status but not with treatment group.. Idebenone did not decrease LV hypertrophy or improve cardiac function in subjects with FRDA. The present study does not provide evidence of benefit in this cohort over a 6-month treatment period.

Topics: Adolescent; Antioxidants; Cardiomyopathy, Hypertrophic; Child; Clinical Trials, Phase III as Topic; Double-Blind Method; Echocardiography, Doppler; Electrocardiography; Female; Friedreich Ataxia; Humans; Hypertrophy, Left Ventricular; Male; Ubiquinone; Ventricular Function

Early mortality in Duchenne muscular dystrophy (DMD) is related to cardiac and respiratory complications. A phase IIa double-blind randomized placebo-controlled clinical trial was conducted to investigate the tolerability and efficacy of idebenone therapy in children with DMD. Twenty-one DMD patients (aged 8-16 years) were randomly assigned to daily treatment with 450 mg idebenone (Catena®) (n=13) or placebo (n=8) for 12 months. All subjects completed the study and idebenone was safe and well tolerated. Idebenone treatment resulted in a trend (p=0.067) to increase peak systolic radial strain in the left ventricular inferolateral wall, the region of the heart that is earliest and most severely affected in DMD. A significant respiratory treatment effect on peak expiratory flow was observed (p=0.039 for PEF and p=0.042 for PEF percent predicted). Limitations of this study were the small sample size, and a skewed age distribution between treatment groups. Data from this study provided the basis for the planning of a confirmatory study.

Topics: Adolescent; Antioxidants; Child; Disease Progression; Dose-Response Relationship, Drug; Double-Blind Method; Forced Expiratory Volume; Humans; Longitudinal Studies; Male; Muscle Strength; Muscular Dystrophy, Duchenne; Natriuretic Peptide, Brain; Treatment Outcome; Troponin I; Ubiquinone; Vital Capacity

Major advances in understanding the pathogenesis of inherited metabolic disease caused by mitochondrial DNA mutations have yet to translate into treatments of proven efficacy. Leber's hereditary optic neuropathy is the most common mitochondrial DNA disorder causing irreversible blindness in young adult life. Anecdotal reports support the use of idebenone in Leber's hereditary optic neuropathy, but this has not been evaluated in a randomized controlled trial. We conducted a 24-week multi-centre double-blind, randomized, placebo-controlled trial in 85 patients with Leber's hereditary optic neuropathy due to m.3460G>A, m.11778G>A, and m.14484T>C or mitochondrial DNA mutations. The active drug was idebenone 900 mg/day. The primary end-point was the best recovery in visual acuity. The main secondary end-point was the change in best visual acuity. Other secondary end-points were changes in visual acuity of the best eye at baseline and changes in visual acuity for both eyes in each patient. Colour-contrast sensitivity and retinal nerve fibre layer thickness were measured in subgroups. Idebenone was safe and well tolerated. The primary end-point did not reach statistical significance in the intention to treat population. However, post hoc interaction analysis showed a different response to idebenone in patients with discordant visual acuities at baseline; in these patients, all secondary end-points were significantly different between the idebenone and placebo groups. This first randomized controlled trial in the mitochondrial disorder, Leber's hereditary optic neuropathy, provides evidence that patients with discordant visual acuities are the most likely to benefit from idebenone treatment, which is safe and well tolerated.

Topics: Adolescent; Adult; Aged; Antioxidants; Contrast Sensitivity; DNA, Mitochondrial; Double-Blind Method; Female; Humans; Male; Middle Aged; Mutation; Optic Atrophy, Hereditary, Leber; Placebos; Prospective Studies; Retina; Ubiquinone; Visual Acuity; Young Adult

To determine the exercise capacity of children and adolescents with Friedreich's Ataxia (FA) and to evaluate the effects of 6 months of idebenone treatment on exercise capacity.. Exploratory endpoint in a randomized double-blind, placebo-controlled, phase II clinical trial designed to investigate the effects of idebenone on a biomarker of oxidative stress.. Exercise physiology laboratory in a single clinical research center.. Ambulatory subjects (N=48; age range, 9-17 y) with genetically confirmed FA.. Idebenone administered orally 3 times a day for a total daily dose of approximately 5, 15, and 45 mg/kg or matching placebo for 6 months.. Peak oxygen consumption per unit time (peak VO(2)) and peak work rate (WR) were measured during incremental exercise testing at baseline and after treatment. Echocardiography and neurologic assessments were also completed before and after treatment.. Baseline mean peak VO(2) +/- SD was 746+/-246 mL/min (16.2+/-5.8 mL/kg/min), and WR was 40+/-23 W for all subjects. Peak VO(2) and WR were correlated with short guanine-adenine-adenine allele length and neurologic function. Relative left ventricular wall thickness was increased but left ventricular ejection fraction was normal in most subjects; there was no relationship between any exercise and echocardiographic measures. There were no significant changes in mean peak VO(2) or WR after idebenone treatment at any dose level relative to placebo.. Exercise capacity in children and adolescents with FA was significantly impaired. The basis for the impairment appears to be multifactorial and correlated to the degree of neurologic impairment. Although idebenone has previously been shown potentially to improve features of FA, idebenone treatment did not increase exercise capacity relative to placebo.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adolescent; Antioxidants; Child; Deoxyguanosine; Dose-Response Relationship, Drug; Double-Blind Method; Exercise Test; Female; Friedreich Ataxia; Humans; Male; Oxidative Stress; Oxygen Consumption; Ubiquinone

To assess the efficacy of idebenone on neurological function in patients with Friedreich ataxia.. Randomized, double-blind, placebo-controlled intervention trial.. Children's Hospital of Philadelphia and the University of California at Los Angeles.. Seventy ambulatory pediatric patients (age, 8-18 years) with a baseline International Cooperative Ataxia Rating Scale (ICARS) score of 10 to 54.. Participants were randomized into 1 of 3 treatment arms: 450 or 900 mg of idebenone per day (in those with a body weight < or = or >45 kg, respectively; n = 22); 1350 or 2250 mg of idebenone per day (n = 24); or placebo (n = 24).. Mean change from baseline to week 24 in ICARS score was the primary efficacy variable. Mean change in Friedreich Ataxia Rating Scale (FARS) score, performance measures, and activities of daily living were the secondary efficacy variables.. Patients who received idebenone improved by 2.5 points on mean ICARS score compared with baseline, while patients in the placebo group improved by 1.3 points. Patients who took idebenone also improved by 1.6 points on the FARS, while patients taking placebo declined by 0.6 points. For both end points, the difference between the idebenone and placebo groups was not statistically different.. Idebenone did not significantly alter neurological function in Friedreich ataxia during the 6-month study. Larger studies of longer duration may be needed to assess the therapeutic potential of drug candidates on neurological function in Friedreich ataxia. Trial Registration clinicaltrials.gov Identifier: NCT00537680.

Topics: Adolescent; Antioxidants; Child; Dose-Response Relationship, Drug; Double-Blind Method; Female; Friedreich Ataxia; Humans; Male; Neurologic Examination; Severity of Illness Index; Ubiquinone

Idebenone is a synthetic analogue of ubiquinone that may be beneficial in the treatment of Friedreich's ataxia. Since in previous pharmacokinetic trials only lower doses were studied, it was the aim of this study to evaluate the pharmacokinetics of idebenone in higher doses of up to 2,250 mg/day.. In this open, randomized trial, 25 healthy male subjects received first either a single oral dose of 150 mg or 750 mg of idebenone, then the same dose given at 8-h intervals for 14 days.. Idebenone and its metabolites appeared in the plasma quickly. Over 99% of parent idebenone was metabolized, indicating a high first-pass effect. C(max) and AUC(0-t) values for parent idebenone and its metabolites increased in a dose-proportional manner. There was virtually no accumulation of parent drug or metabolites following multiple dosing.. Idebenone exhibited dose-dependent pharmacokinetics in daily doses up to 2,250 mg. In 6/14 subjects, adverse events of mild to moderate severity were observed.

Topics: Administration, Oral; Adolescent; Adult; Antioxidants; Area Under Curve; Dose-Response Relationship, Drug; Humans; Male; Metabolic Clearance Rate; Middle Aged; Models, Chemical; Molecular Structure; Reference Standards; Sensitivity and Specificity; Tablets; Time Factors; Ubiquinone; Young Adult

Four phase 1 studies were conducted to assess the pharmacokinetics and metabolism of idebenone (including parent drug and inactive metabolites QS10, QS6, and QS4) and to evaluate the safety of a wide range of idebenone doses and regimens in healthy adult men. After a single oral dose of idebenone 150 mg, 750 mg, or 1050 mg in fasted or fed subjects, blood samples were taken for up to 72 hours. In one study, after a single oral dose and a 7-day washout period, subjects received repeated doses of idebenone 150 mg or 750 mg every 8 hours for 14 days. In the repeated-dose study, urine samples also were taken. Plasma and urine samples were analysed with the use of liquid chromatography with tandem mass spectrometry. Non-compartmental standard pharmacokinetic methods were used. In these studies, a total of 69 subjects ranging in age from 19 to 41 years (body weight, 57-94.6 kg) were included. Plasma concentrations of parent idebenone were low but increased in proportion to dose and increased approximately five-fold in the presence of food. Total QS4 was the main metabolite in plasma and urine. The most common adverse events were loose stool, fatigue, headache, and disturbances in attention. Idebenone was well tolerated in single oral doses up to 1050 mg and in repeated daily doses up to 2250 mg. Idebenone showed linear pharmacokinetics after single and repeated oral dosing. Administration after a meal resulted in the highest exposure to parent idebenone.

Topics: Administration, Oral; Adult; Antioxidants; Biochemical Phenomena; Chromatography, Liquid; Cross-Over Studies; Dose-Response Relationship, Drug; Drug Administration Schedule; Humans; Male; Tandem Mass Spectrometry; Ubiquinone; Young Adult

The purpose of this study was to describe gait parameters in children and adolescents with a diagnosis of Friedreich ataxia (FA) and examine the relationship between disease severity, measured by the Friedreich Ataxia Rating Scale (FARS) and gait parameters. The study examined whether FARS scores can discriminate between those who walk independently and those who require assistance.. Thirty-eight children (aged 5-11 years) and adolescents (aged 12-17 years) with genetically confirmed FA were divided into two groups based on locomotor status: group 1, subjects who were able to walk independently, and group 2, subjects who required assistance for walking. Temporal and spatial gait parameters were collected using the Stride Analyzer computerized foot switch system and compared with age-matched normative data. The FARS was used to measure disease severity. Correlation coefficients and the Mann-Whitney U test of differences were used to evaluate associations and discern differences between groups.. In subjects with FA, gait parameters of velocity and cadence were slower and stride length was shorter compared with age-matched children without disabilities. These parameters were significantly correlated with FARS score (r = 0.696, 0.667, 0.537; respectively, all P values <0.001). Total FARS scores were correlated with locomotor status (ç value r = 0.623; P < 0.01) and could categorize subjects into groups based on independent walking or need for assistance, 73% and 87% of the time, respectively.. Subjects with FA exhibited specific abnormal gait characteristics relative to age-matched individuals. Disease severity, as measured by the FARS, was associated with gait velocity, stride length, and cadence. FARS scores can be used to categorize subjects by locomotor status and may be a useful screening tool to identify those requiring assistance.

Topics: Adolescent; Antioxidants; Child; Child, Preschool; Friedreich Ataxia; Gait; Gait Apraxia; Humans; Motor Activity; Predictive Value of Tests; Severity of Illness Index; Ubiquinone; Walking

Many antioxidants have been suggested as potential treatments for Friedreich ataxia, but have not been tested in clinical trials. We found that a majority of patients in our cohort already use such antioxidants, including idebenone, which is not available at a pharmaceutical grade in the United States. Younger age, cardiomyopathy and shorter GAA repeat length were independent predictors of idebenone use, but no factors predicted use of other antioxidants. This confirms that non-prescription antioxidant use represents a major confounder to formal trials of existing and novel agents for Friedreich ataxia.

Topics: Adolescent; Adult; Age Factors; Age of Onset; Antioxidants; Cardiomyopathies; Clinical Trials as Topic; Cohort Studies; Confounding Factors, Epidemiologic; Dose-Response Relationship, Drug; Drug Therapy, Combination; Female; Friedreich Ataxia; Humans; Male; Middle Aged; Mitochondria; Nonprescription Drugs; Oxidative Stress; Patient Selection; Placebo Effect; Self Medication; Trinucleotide Repeat Expansion; Ubiquinone

Noben (idebenone) was administered in dosage 120 mg during 6 months to 35 patients, aged from 60 to 86 years, with dementia, Alzheimer's type and mixed type, and with memory disturbances which did not reach the level of dementia. The assessment of patient's state before and after treatment was based on the results of somatic, neurological and psychiatric examination as well as neuropsychological testing and using of psychometrical and other scales. The significant improvement on the MMSE scale was found in patients with mild and moderate dementia. The improvement of daily activity was observed in 27% of patients. The neuropsychological study revealed the improvement of short-term and delayed memory and attention, speech functions, the performance on kinesthetic, spatial and dynamic praxis tests, visual-spatial gnosis, reasoning and writing. The positive therapeutic effect assessed by the CGI scale was observed in 37% of patients, the stable state--in 48%.

Topics: Aged; Aged, 80 and over; Antioxidants; Attention; Cognition; Cognition Disorders; Dementia; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Humans; Male; Memory; Middle Aged; Neuropsychological Tests; Severity of Illness Index; Time Factors; Treatment Outcome; Ubiquinone

Friedreich ataxia (FA) is the most frequent autosomal recessive cerebellar ataxia. Although the phenotype is well known, disease progression has not been evaluated in a prospective manner.. To perform a long-term prospective follow-up of neurological, cardiological, and oculomotor function in patients with FA (FA patients).. In this open-labeled prospective survey, we examined 104 FA patients every 6 months during a median period of 5 years (range, 6 months to 7 years), with a systematic standardized protocol. Data are reported as mean +/- SD.. Neurological examinations were performed at the Federation of Neurology and the Department of Genetics of the Salpêtrière Hospital, Paris, France. Cardiological follow-up was performed at the Department of Cardiology; oculomotor examinations were performed at the Institut National de la Santé et de la Récherche Médicale Unit 679, at the same hospital. Patients We studied 104 FA patients with a confirmed molecular diagnosis. None were receiving antioxidant therapy at baseline; 88 accepted treatment with the coenzyme Q(10) analogue idebenone (5 mg/kg per day). Sixteen preferred not to be treated.. Neurological status was evaluated with the International Cooperative Ataxia Rating Scale (ICARS) and a quantitative writing test. Cardiological evaluations included echocardiography, electrocardiography, and Holter monitoring. Oculomotor function was evaluated by electro-oculography to determine the frequency of square wave jerks.. The total ICARS score worsened during follow-up, whether or not the patients were treated with idebenone (1.93 +/- 0.25 and 4.43 +/- 1.56 points per year, respectively). The total ICARS score increased faster in patients with onset before age 15 years compared with the others (2.6 +/- 0.4 [n = 51] vs 1.1 +/- 0.3 [n = 37]; P = .05). The posture subscore increased faster in patients able to stand at baseline, who also had shorter disease durations than patients unable to stand (1.25 +/- 0.12 vs 0.47 +/- 0.22 point per year; P<.001). Neurological progression was underestimated, however, by the ICARS scores, which reached a plateau in patients with long disease durations. Oculomotor function slightly deteriorated (0.09 +/- 0.02 Hz per year; P<.001). Left ventricular mass index decreased (-4.1 +/- 1.5 g/m(2) per year; P = .008), as did ejection fraction (-1.32% +/- 0.29% per year; P<.001).. The neurological condition of FA patients deteriorated slowly over time, even with idebenone treatment. Although cardiac hypertrophy decreased under treatment, cardiac function did not improve. The ICARS scale is not appropriate to evaluate the progression of FA in patients with long disease durations. Additional quantitative measures may improve the reliability of this scale.

Topics: Adolescent; Adult; Aged; Antioxidants; Benzoquinones; Disease Progression; Echocardiography; Electrocardiography, Ambulatory; Electrooculography; Follow-Up Studies; Frataxin; Friedreich Ataxia; Humans; Iron-Binding Proteins; Middle Aged; Neurologic Examination; Paris; Prospective Studies; Time Factors; Treatment Outcome; Trinucleotide Repeat Expansion; Ubiquinone

Friedreich ataxia (FA) is a progressive, multisystem degenerative disorder in which oxidative stress is believed to have a role. Recent clinical studies indicate that the antioxidant idebenone, administered at 5 mg/kg per day, reduces the cardiac hypertrophy that occurs in FA, but improvement in neurologic measures is unclear. Some studies suggest that higher doses of idebenone may be more effective, but pharmacology and toxicology at higher doses have not been investigated in human beings.. To determine the safety, tolerability, and pharmacokinetics of increasing doses of idebenone in subjects with FA.. Open-label, phase 1A dose-escalation trial followed by an open-label, 1-month phase 1B trial.. National Institutes of Health Clinical Center, Bethesda, Md.. Phase 1A included 78 subjects with FA (24 adults, 27 adolescents, and 27 children), and phase 1B included 15 subjects with FA (5 adults, 5 adolescents, and 5 children).. Oral idebenone was administered to groups of 3 subjects in each age cohort during day 1. In phase 1A, the dose was increased in 10-mg/kg increments in each successive dose group to a maximum of 75 mg/kg. In phase 1B, oral idebenone was administered at 60 mg/kg divided in 3 doses per day for 1 month.. We studied the type, number, and frequency of adverse events, and pharmacokinetic parameters including maximum drug concentration, time to maximum drug concentration, area under the curve, and half-life.. In the first phase of the study, no dose-limiting toxicity was observed and the maximum allowed dose of 75 mg/kg was achieved in all cohorts. Plasma levels of total idebenone were found to increase proportional to drug dose up to 55 mg/kg. Variability in absorption of the drug was observed, but drug half-life was relatively consistent across dose levels. In the second phase of the study, 14 of 15 subjects with FA tolerated idebenone at a dose of 60 mg/kg per day for 1 month. All adverse events were mild, and pharmacokinetic parameters including maximum drug concentration, time to maximum drug concentration, and half-life did not differ significantly across age cohorts.. These findings indicate that higher doses of idebenone lead to a proportional increase in plasma levels up to 55 mg/kg per day and that high-dose idebenone is well-tolerated in patients with FA. These findings are essential to planning efficacy trials of high-dose idebenone in FA and other degenerative diseases in which oxidative damage has been implicated.

Topics: Absorption; Administration, Oral; Adolescent; Adult; Antioxidants; Benzoquinones; Child; Dose-Response Relationship, Drug; Female; Friedreich Ataxia; Half-Life; Humans; Male; Osmolar Concentration; Time Factors; Ubiquinone

Friedreich's ataxia (FA) is a progressive, multisystem, degenerative disorder caused by a reduction in frataxin. Loss of frataxin results in mitochondrial dysfunction and oxidative damage in patients and model systems. Previous studies have indicated that the antioxidant idebenone (5 mg/kg daily) reduces cardiac hypertrophy, but definite improvement in neurological function has not been shown.. 48 genetically confirmed FA patients, aged 9-17 years, were enrolled in a 6-month, randomised, double-blind, placebo-controlled study. The patients received placebo or one of three doses of idebenone (approximately 5 mg/kg, 15 mg/kg, and 45 mg/kg), stratified by body weight. The primary endpoint was change from baseline in urinary 8-hydroxy-2'-deoxyguanosine (8OH2'dG), a marker of oxidative DNA damage. Secondary endpoints included changes in the international cooperative ataxia rating scale (ICARS), the FA rating scale (FARS), and a survey of activities of daily living (ADL). This study is registered with ClinicalTrials.gov, number NCT00229632.. Idebenone was generally well tolerated with similar numbers of adverse events in each group. One child receiving high-dose idebenone developed neutropenia after 6 months, which resolved after discontinuation of treatment. 8OH2'dG concentrations were not increased, and did not significantly change with idebenone treatment. Whereas an overall analysis did not show a significant difference in ICARS, FARS, or ADL total scores, there were indications of a dose-dependent response in the ICARS score. A second, pre-specified analysis, excluding patients who required wheelchair assistance, showed a significant improvement in ICARS (Bonferroni p=0.03) and suggested a dose-related response in ICARS, FARS, and ADL scores.. Treatment with higher doses of idebenone was generally well tolerated and associated with improvement in neurological function and ADL in patients with FA. The degree of improvement correlated with the dose of idebenone, suggesting that higher doses may be necessary to have a beneficial effect on neurological function.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Activities of Daily Living; Adolescent; Antioxidants; Benzoquinones; Child; Deoxyguanosine; DNA Damage; Dose-Response Relationship, Drug; Female; Friedreich Ataxia; Humans; Male; Nervous System; Neutropenia; Severity of Illness Index; Ubiquinone

The authors carried out a 1-year, randomized, placebo-controlled trial of idebenone in 29 patients with Friedreich ataxia. They found significant reductions of interventricular septal thickness and left ventricular mass in the idebenone group vs the placebo group, with no improvement in other heart ultrasound measures or neurologic condition. The absolute cardiac changes were modest, but the findings suggest that larger trials should assess whether idebenone reduces ventricular hypertrophy in patients with Friedreich ataxia.

Topics: Adolescent; Adult; Benzoquinones; Cardiomyopathy, Hypertrophic; Child; Erythrocytes; Female; Frataxin; Free Radical Scavengers; Free Radicals; Friedreich Ataxia; Humans; Hypertrophy, Left Ventricular; Iron-Binding Proteins; Male; Mitochondria; Oxidative Stress; Prospective Studies; Protoporphyrins; Ubiquinone

The authors report 1-year prospective data on eight patients with Friedreich ataxia. Idebenone did not halt the progression of ataxia. At the end of therapy, cardiac ultrasound demonstrated significant reduction of cardiac hypertrophy in six of eight patients. Cardiac strain and strain rate imaging showed that the reduction of hypertrophy is preceded by an early and linear improvement in cardiac function. Idebenone reduced erythrocyte protoporphyrin IX levels in five of six patients with elevated baseline levels; however, changes did not consistently relate to cardiac improvement.

Topics: Adolescent; Adult; Benzoquinones; Cardiomyopathy, Hypertrophic; Child; Erythrocytes; Female; Frataxin; Free Radical Scavengers; Free Radicals; Friedreich Ataxia; Humans; Hypertrophy, Left Ventricular; Iron-Binding Proteins; Male; Mitochondria; Oxidative Stress; Prospective Studies; Protoporphyrins; Stroke Volume; Ubiquinone

To determine the effect of idebenone on the rate of decline in Alzheimer's disease (AD).. A 1-year, multicenter, double-blind, placebo-controlled, randomized trial was conducted. Subjects were over age 50 with a diagnosis of probable AD and had Mini-Mental State Examination (MMSE) scores between 12 and 25. Subjects were treated with idebenone 120, 240, or 360 mg tid, each of which was compared with placebo. Primary outcome measures were the Alzheimer's Disease Assessment Scale-Cognitive Subcomponent (ADAS-Cog) and a Clinical Global Impression of Change (CGIC). Secondary outcome measures included measurements of activities of daily living, the Behavioral Pathology in Alzheimer's Disease Rating Scale, and the MMSE.. Five hundred thirty-six subjects were enrolled and randomized to the four groups. Except for a slight difference in age, there were no differences in patient characteristics at baseline. For the primary outcome measures, there were no significant overall differences between the treatment groups in the prespecified four-group design. In an exploratory two-group analysis comparing all three treated groups combined with placebo, drug-treated patients performed better on the ADAS-Cog in both the intent-to-treat (ITT) and completers analyses. There were no differences in the CGIC scores for the ITT or completers analyses in either the four-group or the two-group analyses. There were no overall differences on any of the secondary outcome measures in any of the analyses.. Idebenone failed to slow cognitive decline in AD that was of sufficient magnitude to be clinically significant.

Topics: Aged; Alzheimer Disease; Benzoquinones; Cognition Disorders; Disease Progression; Double-Blind Method; Female; Humans; Male; Middle Aged; Treatment Failure; Ubiquinone

Antioxidant therapy has been applied to Friedreich's ataxia patients. We assessed the effect of idebenone treatment in patients with Friedreich's ataxia.. open-label trial. Nine Friedreich's ataxia patients (age range 11 - 19 years) were treated with idebenone (5 mg/kg/day). Patients were evaluated before the start of the therapy and throughout one year of treatment by International Cooperative Ataxia Rating Scales (ICARS) scores, neurophysiological investigations and echocardiographic measurements. Serum idebenone concentrations were measured by HPLC with electrochemical detection. The number of GAA repeats at the frataxin gene was analyzed by PCR.. Serum idebenone concentrations ranged between 0.04 - 0.37 micro mol/L. Significantly positive correlation was observed between idebenone values and the percentage of difference between the ICARS scores before and 12 months after the start of the therapy (r = 0.883; p = 0.002). Significant reduction was observed comparing the ICARS scores in baseline conditions and after 3 months of treatment (p = 0.017). No differences were observed in echocardiographic measurements after the start of the therapy.. Cerebellar improvement was notable in mild patients after the first 3 months of therapy. Idebenone treatment at early stages of the disease seems to reduce the progression of cerebellar manifestations. Further blind trials with a greater number of patients and higher doses are needed to fully assess the therapeutic potential of idebenone in Friedreich's ataxia.

Topics: Adolescent; Adult; Antioxidants; Benzoquinones; Cerebellum; Child; Echocardiography; Female; Follow-Up Studies; Friedreich Ataxia; Humans; Male; Recovery of Function; Time Factors; Ubiquinone

This study evaluated the safety and efficacy of idebenone vs. tacrine in a prospective, randomized, double-blind, parallel-group multicenter study in patients suffering from dementia of the Alzheimer type (DAT) of mild to moderate degree. Diagnosis was based on DSM-III-R (primary degenerative dementia) and NINCDS-ADRDA criteria (probable Alzheimer's disease). A total of 203 patients of both sexes aged between 40 and 90 years were randomized to either idebenone 360 mg/day (n = 104) or tacrine up to 160 mg/day (n = 99) and treated for 60 weeks. The primary outcome measure was the Efficacy Index Score (EIS). The EIS combines dropout as well as the relevant improvements individually across the three levels of assessment (cognitive function, activities of daily living, global function). Secondary outcome measures were the ADAS-Cog score, the NOSGER-IADL score and the clinical global response (CGI-Improvement). After 60 weeks of treatment, 28.8 % of the patients randomized to idebenone, but only 9.1 % of the patients randomized to tacrine were still on the drug. In the LOCF analysis, 50 % of the patients randomized to idebenone but only 39.4 % of the patients randomized to tacrine showed an improvement in the Efficacy Index Score or at least one of the secondary outcome variables. The primary efficacy measurement was the change of the Efficacy Index Score from baseline to the assessment after 60 weeks treatment. The analysis was done on intention-to-treat (ITT) in a before-and-after test design. Patients randomized to idebenone showed a higher benefit from treatment than patients randomized to tacrine. We conclude that the benefit-risk ratio is favorable for idebenone compared to tacrine, and furthermore, that this ratio is likely to be similar when comparing idebenone to other cholinesterase inhibitors.

Topics: Adult; Aged; Aged, 80 and over; Alzheimer Disease; Antioxidants; Benzoquinones; Double-Blind Method; Female; Humans; Male; Middle Aged; Nootropic Agents; Tacrine; Treatment Outcome; Ubiquinone

Friedreich's ataxia encodes a protein of unknown function, frataxin. The loss of frataxin is caused by a large GAA trinucleotide expansion in the first intron of the gene, resulting in deficiency of a Krebs cycle enzyme, aconitase, and of three mitochondrial respiratory chain complexes (I-III). This causes oxidative stress. Idebenone, a short chain quinone acting as an antioxidant, has been shown to protect heart muscle against oxidative stress in some patients.. To assess the efficiency of idebenone on cardiac hypertrophy in Friedreich's ataxia.. Prospective, open trial.. Tertiary care centre.. Idebenone (5 mg/kg/day) was given orally to 38 patients with Friedreich's ataxia aged 4-22 years (20 males, 18 females). Cardiac ultrasound indices were recorded before and after idebenone treatment.. After six months, cardiac ultrasound indicated a reduction in left ventricular mass of more than 20% in about half the patients (p < 0.001). The shortening fraction was initially reduced in six of the 38 patients (by between 11-26%) and it improved in five of these. In one patient, the shortening fraction only responded to 10 mg/kg/day of idebenone. No correlation was found between responsiveness to idebenone and age, sex, initial ultrasound indices, or the number of GAA repeats in the frataxin gene.. Idebenone is effective at controlling cardiac hypertrophy in Friedreich's ataxia. As the drug has no serious side effects, there is a good case for giving it continuously in a dose of 5-10 mg/kg/day in patients with Friedreich's ataxia at the onset of hypertrophic cardiomyopathy.

Topics: Adolescent; Adult; Antioxidants; Benzoquinones; Cardiomegaly; Child; Child, Preschool; Female; Friedreich Ataxia; Humans; Male; Prospective Studies; Stroke Volume; Treatment Outcome; Ubiquinone; Ventricular Dysfunction, Left

Friedreich ataxia (FA), the most common form of degenerative ataxia, is thought to be caused by respiratory deficiency due to mitochondrial iron accumulation and oxidative stress. Idebenone, a free-radical scavenger, protects mitochondrial function in in vitro models of FA. In a placebo-controlled crossover trial we studied the effect of idebenone on respiratory function in nine ambulant FA patients. (31)P magnetic resonance spectroscopy demonstrated mitochondrial impairment in vivo in skeletal muscle of all FA patients, but no recovery with idebenone. No effects were seen in clinical scores. Echocardiography did not confirm a preliminary study reporting improvement of FA-associated cardiomyopathy with idebenone.

Topics: Antioxidants; Benzoquinones; Cardiomyopathies; Cross-Over Studies; Echocardiography; Female; Friedreich Ataxia; Humans; Magnetic Resonance Spectroscopy; Male; Mitochondria; Muscle, Skeletal; Radionuclide Imaging; Ubiquinone

Within a general cerebral deficit model--inspiratory hypoxia-the dose--effect relationship of idebenone (CAS 58186-27-9), an antioxidant, was studied with regard to selected electrophysiological and psychometric parameters. Seventeen healthy male volunteers (mean age = 32 years, mean BW = 75 kg) received three different oral medications: placebo, idebenone and piracetam (CAS 7491-74-9) as reference. The test drug idebenone was administered in five different dosages, ranging--in 60 mg steps--from 60 to 300 mg t.id. Piracetam was given at a dose level of 800 mg t.i.d. A strict dose-regimen was used in idebenone for safety reasons. Each dosage/medication--except idebenone 300 mg t.i.d.--was given for one week without washouts in between. On each 7th treatment day, pharmacodynamic assessments comprising electroretinography (ERG), auditory evoked potentials (AEP) and visual analogue scales (VAS) were run. Immediately after the phases with the lower dosages, the study was continued with the highest dosage of idebenone (300 mg t.i.d.) for a period of four weeks with pharmacodynamic assessments on the 7th, 14th and 28th day. In this pilot study, the target variable, the amplitude of the ERG b-wave indicated a definite antihypoxidotic effect after the highest dosage of idebenone. With 300 mg idebenone t.i.d., ERG b-wave amplitudes increased linearily with increasing duration of treatment. The 'central' AEP P2-amplitude demonstrated a different dose-effect relationship. AEP P2-amplitudes increased with increasing dosages of idebenone. The prolongation of treatment with 300 mg t.i.d. resulted in no further improvement of this parameter (ceiling effect). Subjective ratings (VAS) by the volunteers confirmed the results seen in electrophysiological variables. The findings, however, remain to be confirmed within an adequate double-blind, crossover study design.

Topics: Adult; Antioxidants; Benzoquinones; Dose-Response Relationship, Drug; Electrophysiology; Electroretinography; Evoked Potentials, Auditory; Humans; Hypoxia, Brain; Male; Nootropic Agents; Piracetam; Psychometrics; Ubiquinone

The 2-year efficacy and safety of idebenone were studied in a prospective, randomized, double-blind multicentre study in 3 parallel groups of patients with dementia of the Alzheimer type (DAT) of mild to moderate degree. A total of 450 patients were randomized to either placebo for 12 months, followed by idebenone 90 mg tid for another 12 months (n = 153) or idebenone 90 mg tid for 24 months (n = 148) or 120 mg tid for 24 months (n = 149). The primary outcome measure was the total score of the Alzheimer's Disease Assessment Scale (ADAS-Total) at month 6. Secondary outcome measures were the ADAS cognitive (ADAS-Cog) and noncognitive score (ADAS-Noncog), the clinical global response (CGI-Improvement), the SKT neuropsychological test battery, and the Nurses' Observation Scale for Geriatric Patients (NOSGER-Total and IADL subscale). Safety parameters were adverse events, vital signs, ECG and clinical laboratory parameters. During the placebo controlled period (the first year of treatment), idebenone showed statistically significant dose-dependent improvement in the primary efficacy variable ADAS-Total and in all the secondary efficacy variables. There was no evidence for a loss of efficacy during the second year of treatment, as a further improvement of most efficacy variables was found in the second year in comparison to the results at the 12 months visit. Also, a clear dose effect relationship (placebo/90 mg < idebenone 90 mg < idebenone 120 mg) was maintained throughout the second year of treatment. This suggests that idebenone exerts its beneficial therapeutic effects on the course of the disease by slowing down its progression. Safety and tolerability of idebenone were good and similar to placebo during the first year of treatment and did not change during the second year.

Topics: Adult; Aged; Aged, 80 and over; Alzheimer Disease; Antioxidants; Benzoquinones; Dose-Response Relationship, Drug; Double-Blind Method; Female; Follow-Up Studies; Humans; Male; Middle Aged; Prospective Studies; Psychiatric Status Rating Scales; Time Factors; Ubiquinone

Two doses of idebenone were studied in a prospective, randomized, double-blind, placebo-controlled multicentre study in patients suffering from dementia of the Alzheimer type (DAT) of mild to moderate degree. Diagnosis was based on DSM-III-R (primary degenerative dementia) and NINCDS-ADRDA criteria (probable Alzheimer's disease). A total of 300 patients were randomized to either placebo, idebenone 30 mg t.i.d. or 90 mg t.i.d. (n = 100, each) and treated for 6 months. The primary outcome measure was the total score of the Alzheimer's Disease Assessment Scale (ADAS-Total) at month 6. Secondary outcome measures were the ADAS cognitive (ADAS-Cog) and noncognitive scores (ADAS-Noncog), the clinical global response (CGI-Improvement), the MMSE, the Digit Symbol Substitution test (DSS) and several scales for the assessment of daily activities (the self- and observer-rating scales NAA and NAB of the Nuremberg Age Inventory NAI and Greene's Assessment). Safety parameters were adverse events, vital signs, ECG and clinical laboratory parameters. Clinical and psychometric evaluations were performed at baseline, and after 1, 3 and 6 months of treatment. After month 6 idebenone 90 mg t.i.d. showed statistically significant improvement in the primary efficacy variable ADAS-Total and in ADAS-Cog. An analysis of therapy responders performed for 3 outcome measures (CGI-global improvement, ADAS-Cog, ADAS-Noncog), selected to represent different domains of assessment, revealed significant superiority of idebenone 90 mg t.i.d. with respect to placebo in each of the 3 variables and in the concordance of responses across the 3 measures. Exploratory results for a subgroup of patients (ADAS-Total > or = 20) showed dose-related superiority of idebenone additionally on ADAS-Noncog and the CGI-Improvement scale. Safety results were inconspicuous for all assessments. The study results demonstrate the efficacy and safety of idebenone in the treatment of DAT patients.

Topics: Aged; Aged, 80 and over; Alzheimer Disease; Benzoquinones; Cognition; Double-Blind Method; Female; Humans; Male; Middle Aged; Treatment Outcome; Ubiquinone

One hundred patients with clinically diagnosed Huntington's disease (HD) were randomized to either idebenone, an antioxidant and enhancer of oxidative metabolism, or placebo, in a 1-year, double-blind, parallel-group study aimed at slowing the rate of progression of the disease. Ninety-one patients completed the study. There were no significant differences between groups on the primary outcome measures of the Huntington's Disease Activities of Daily Living Scale (ADL-an index of functional status) and the Quantified Neurologic Examination (QNE). Sample size calculations based on progression of the ADL and QNE in this study group revealed that a larger study group is necessary to detect any differences less than an almost complete halting of the disease. This argues for multicenter efforts for future therapeutic trials in HD.

Topics: Activities of Daily Living; Adult; Antioxidants; Benzoquinones; Double-Blind Method; Female; Humans; Huntington Disease; Longitudinal Studies; Male; Middle Aged; Placebos; Receptors, Glutamate; Treatment Outcome; Ubiquinone

Topics: Antioxidants; DNA, Mitochondrial; Humans; Optic Atrophy, Hereditary, Leber; Ubiquinone

Topics: Antioxidants; Humans; Optic Atrophy, Hereditary, Leber; Ubiquinone

In this retrospective, interventional, longitudinal small case series, we looked at the visual effects of pharmacologic intervention with 4-aminopyridine (4-AP) in chronic Leber's Hereditary Optic Neuropathy (LHON) patients who are non-responders to idebenone. We illustrate, as examples, the visual progression of three LHON patients with 4-AP as add-on therapy to idebenone. Each patient had a different primary LHON mutation and was treated with idebenone within one year of onset. No response to idebenone at 300 mg orally three times a day ranged from less than one year to 2.5 years, and the addition of 4-AP at 10 mg orally two times a day ranged from 24 to 29 months. Outcome measures included best-corrected distance visual acuity, color vision, automated perimetry, the average retinal nerve fiber layer (RNFL) thickness, and the full-field photopic negative response (PhNR) amplitude. The 19-year-old man with the LHON mutation 11778A > G had no response to the addition of 4-AP to idebenone. The 27-year-old man with the LHON mutation 3460A > G experienced a significant response to 4-AP. Finally, the 40-year-old man with the LHON mutation 14484 T > C had a milder response. Although this case series was too small to demonstrate the efficacy of idebenone with add-on 4AP, it allowed us to consider a new hypothesis that neuronal activity generated from 4-AP can add more potential for visual recovery in LHON patients.

Topics: 4-Aminopyridine; Adult; DNA, Mitochondrial; Drug Therapy, Combination; Humans; Male; Nerve Net; Neurons; Optic Atrophy, Hereditary, Leber; Retrospective Studies; Ubiquinone; Young Adult

The reproductive function of animals is often affected by climatic conditions. High-temperature conditions can cause damage to oocyte maturation and embryonic development in a variety of ways. The purpose of this study was to prove that supplementation idebenone (IDB) to the maturation medium can improve the maturation and development of porcine oocytes after heat stress (HS). Porcine cumulus-oocyte complexes (COCs) were cultured in the maturation medium with different concentrations of IDB (0, 0.1, 1 and 10 μM) for 44 hr at either 38.5°C or under the HS conditions. The cumulus oophorus expansion, nuclear maturation and blastocyst rate after parthenogenetic activation (PA) were measured. We found that HS (in vitro maturation 20-24 hr, 42°C) exposure significantly reduced cumulus expansion index and maturation rate of oocytes and the blastocyst rate of PA embryos, while IDB supplementation significantly improved oocyte maturation and development to the blastocysts stage after PA. Moreover, the addition of IDB decreased the intracellular level of ROS and increased GSH content, hence enhancing the antioxidant capacity of oocytes under HS. Meanwhile, IDB treatment also obviously improved the mitochondrial membrane potential and ATP synthesis of oocytes under HS conditions. Furthermore, IDB treatment increased the expression of GDF9 and BMP15 in IVM oocytes which attribute to improve the quality and outcome of IVM oocytes and the development competence of PA embryos in pigs. In summary, we demonstrated that IDB supplementation into the maturation medium exerted protective effects and improved the ability of maturation and developmental competence of porcine oocytes exposed to HS.

Topics: Animals; Blastocyst; Embryonic Development; Female; Heat-Shock Response; In Vitro Oocyte Maturation Techniques; Oocytes; Pregnancy; Swine; Ubiquinone

Biodegradable poly(lactic-co-glycolic acid) microspheres (PLGA MSs) are attractive delivery systems for site-specific maintained release of therapeutic active substances into the intravitreal chamber. The design, development, and characterization of idebenone-loaded PLGA microspheres by means of an oil-in-water emulsion/solvent evaporation method enabled the obtention of appropriate production yield, encapsulation efficiency and loading values. MSs revealed spherical shape, with a size range of 10-25 μm and a smooth and non-porous surface. Fourier-transform infrared spectroscopy (FTIR) spectra demonstrated no chemical interactions between idebenone and polymers. Solid-state nuclear magnetic resonance (NMR), X-ray diffractometry, differential scanning calorimetry (DSC) and thermogravimetry (TGA) analyses indicated that microencapsulation led to drug amorphization. In vitro release profiles were fitted to a biexponential kinetic profile. Idebenone-loaded PLGA MSs showed no cytotoxic effects in an organotypic tissue model. Results suggest that PLGA MSs could be an alternative intraocular system for long-term idebenone administration, showing potential therapeutic advantages as a new therapeutic approach to the Leber's Hereditary Optic Neuropathy (LHON) treatment by intravitreal administration.

Topics: Humans; Microspheres; Optic Atrophy, Hereditary, Leber; Particle Size; Polylactic Acid-Polyglycolic Acid Copolymer; Ubiquinone

The use of proper nanocarriers for dermal and transdermal delivery of anti-inflammatory drugs recently gained several attentions in the scientific community because they pass intact and accumulate payloads in the deepest layers of skin tissue. Ascorbyl palmitate-based vesicles (aspasomes) can be considered a promising nanocarrier for dermal and transdermal delivery due to their skin whitening properties and suitable delivery of payloads through the skin. The aim of this study was the synthesis of multidrug Idebenone/naproxen co-loaded aspasomes for the development of an effective anti-inflammatory nanomedicine. Aspasomes had suitable physicochemical properties and were safe in vivo if topically applied on human healthy volunteers. Idebenone/naproxen co-loaded aspasomes demonstrated an increased therapeutic efficacy of payloads compared to the commercially available Naprosyn® gel, with a rapid decrease of chemical-induced erythema on human volunteers. These promising results strongly suggested a potential application of Idebenone/naproxen multidrug aspasomes for the development of an effective skin anti-inflammatory therapy.

Topics: Administration, Cutaneous; Anti-Inflammatory Agents; Drug Delivery Systems; Humans; Naproxen; Skin; Skin Absorption; Ubiquinone

Topics: Amyloid beta-Peptides; Animals; Cognition; Female; Inflammasomes; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; NF-E2-Related Factor 2; NLR Family, Pyrin Domain-Containing 3 Protein; Ubiquinone

To evaluate the efficacy of the energotropic drug idebenon in hereditary neuromuscular pathology.. A total of 9 patients with hereditary myopathies were examined during treatment with idebenone. Determination of muscle strength was carried out on the British medical research Council scale (0 points - no active movements, 5 points - no muscle weakness). The examination was performed before and 1 month after the start of treatment. Treatment regimen: idebenone was prescribed in a daily dose of 90 mg.. In the general group of patients with hereditary ataxia, the median strength of the biceps muscle of the shoulder during treatment increased from 3.5 to 4.0 points (. We used the energotropic drug idebenon, a synthetic analog of the natural substance coenzyme Q10, which is involved in electron transfer in the mitochondrial respiratory chain complex III, for the treatment of patients with hereditary myopathies. In the general group of patients, there was an increase in muscle strength, although it did not reach statistical significance. Before the advent of energotropic drugs, the use of various methods of treating hereditary myopathies did not lead to an increase in muscle strength in patients. Therefore, the identified positive dynamics is of great importance in providing medical care to these patients and improving their quality of life.. Оценить эффективность энерготропного препарата идебенон при наследственной нервно-мышечной патологии.. Всего обследованы 9 больных с наследственными миопатиями на фоне лечения идебеноном. Определение мышечной силы проводили по шкале Британского медицинского исследовательского совета (BMRC) (0 баллов — отсутствие активных движений, 5 баллов — отсутствие мышечной слабости). Обследование проводили до и через 1 мес после начала лечения. Идебенон назначали в суточной дозе 90 мг.. В общей группе больных наследственными атаксиями медиана силы двуглавой мышцы плеча на фоне лечения увеличилась с 3,5 до 4,0 баллов (. Для лечения больных наследственными миопатиями был применен энерготропный препарат идебенон — синтетический аналог природного вещества коэнзима Q10, участвующего в переносе электронов в III комплексе дыхательной цепи митохондрий. В общей группе обследуемых отмечено увеличение мышечной силы, хотя и не имеющее статистической значимости. До появления энерготропных препаратов применение различных методов лечения наследственных миопатий не приводило к увеличению мышечной силы. Поэтому выявленная положительная динамика у больных имеет большое значение при оказании медицинской помощи и улучшении качества их жизни.

Topics: Antioxidants; Humans; Muscle Weakness; Muscular Diseases; Pilot Projects; Quality of Life; Ubiquinone

To evaluate the therapeutic effects of methylprednisolone, the CoenzymeQ10 (CoQ10) structural analogue idebenone, and both together on the optic nerve (ON) and retinal layers following methanol intoxication in rats with histopathological and biochemical methods.. This experimental study was conducted with 30 male Wistar rats. The rats were divided into five equal groups depending on the treatment protocol:healthy controls (HC), methanol (M), methanol + methylprednisolone (MM), methanol + idebenone (MI), and methanol + methylprednisolone + idebenone (MMI).Distilled water was provided orally to the HC group, while 20% methanol was administered orally at a dose of 3 g/kg with a nasogastric tube to all rats in groups except the HC group. Four hours later, group MM received 1 mg/kg of intraperitoneal methylprednisolone for 10 days using an insulin syringe, and group MI received 20 mg/kg idebenone by nasogastric catheter for 28 days. MMI group was administered oral idebenone and intraperitoneal methylprednisolone at the same dose. Serum samples were obtained on the 28. Comparison of the antioxidant and oxidative stress biomarkers between the groups revealed no statistically significant difference (. The early use (within hours) of idebenone and short-term methylprednisolone treatment together may protect against the retinal and ON damage developing after methanol ingestion in rats as guided by the histopathological data.

Topics: Adrenal Cortex Hormones; Animals; Male; Methanol; Methylprednisolone; Optic Nerve; Rats; Rats, Wistar; Retinal Diseases; Ubiquinone

Reactive oxygen species (ROS) are overproduced in diabetic wounds and retard the healing response. Considering the antioxidative function of idebenone, its exogenous administration may quench excessive ROS and promote diabetic wound healing. In the current study, idebenone was loaded into polyvinyl alcohol (PVA) /calcium alginate scaffolds at three different concentrations of 1 w/w%, 2 w/w%, and 3 w/w%. Various in vitro experiments were performed to characterize the developed wound dressings. Cell viability assay showed that scaffolds loaded with 1 w/w% idebenone had significantly better protection under oxidative stress and exhibited higher cell viability. Therefore, the dressings containing 1% drug was chosen to treat diabetic wounds in rat model. Wound healing assay showed that the dressings loaded with 1% drug had significantly higher rate of wound size reduction, collagen deposition, and epithelial thickness. Gene expression study showed that wound healing was accompanied by modulation of inflammatory response, protection against oxidative stress, and increasing angiogenesis-related genes. This preliminary research suggests that PVA/calcium alginate/1% idebenone scaffolds can be considered as a potential treatment modality to treat diabetic wounds in the clinic. However, more extensive studies at gene and protein expression levels are required to understand its exact mechanism of healing effects.

Topics: Alginates; Animals; Bandages; Diabetes Mellitus; Down-Regulation; Fibroblast Growth Factor 2; Interleukin-1beta; Polyvinyl Alcohol; Rats; Reactive Oxygen Species; Rodent Diseases; Ubiquinone; Up-Regulation; Wound Healing

Sepsis is an uncontrolled systemic infection, withcomplex pathophysiology that may result in acute lung organ damage and cause multiple organ failure. Although much research has been conducted to illuminate sepsis's complex pathophysiology, sepsis treatment protocols are limited, and sepsis remains an important cause of mortality andmorbidity in intensive care units.Various studies have shown that idebenone (IDE) possesses strong antioxidant properties, which inhibit lipid peroxidation and protect cells from oxidative damage. The present study aimed to evaluate the protective effects of IDE against lung injury in a cecal ligation and puncture (CLP)-induced sepsis rat model.. Male albino Wistar rats were used. The animals were divided into a healthy control (no treatment), CLP, IDE control (200 mg/kg), and CLP + IDE subgroups (50 mg/kg, 100 mg/kg, and 200 mg/kg), with nine rats in each group.IDE was administered 1 h after CLP induction.To evaluate the protective effects of IDE, lung tissues were collected 16 h after sepsis for biochemical, immunohistochemical staining, and histopathological examination.. IDE significantly ameliorated sepsis-induced disturbances in oxidative stress-related factors, with its effects increasing in accordance with the dose.IDE also abolished histopathological changes in lung tissues associated with CLP.Furthermore, interleukin 1 beta (IL-1β)and tumor necrosis factor-alpha (TNF-α) immunopositivity markedly decreased in the septic rats following IDE treatment.. IDE largely mitigated the inflammatory response in sepsis-induced lung injury by decreasing free radicals and preventing lipid peroxidation. The results suggest that IDE may represent a potential novel therapeutic drug for sepsis treatment.

Topics: Animals; Disease Models, Animal; Lung; Male; Oxidative Stress; Rats; Rats, Wistar; Sepsis; Ubiquinone

Leber's Hereditary Optic Neuropathy (LHON) is a hereditary mitochondrial neurodegenerative disease of unclear etiology and lack of available therapeutic alternatives. The main goal of the current pilot study was based on the evaluation of the feasibility and characteristics of prolonged and controlled idebenone release from a PCL intravitreal implant. The design, development, and characterization of idebenone-loaded PCL implants prepared by an homogenization/extrusion/solvent evaporation method allowed the obtention of high PY, EE and LC values. In vitro characterization was completed by the assessment of mechanical and instrumental properties. The in vitro release of idebenone from the PCL implants was assessed and the implant erosion was monitored by the mass loss and surface morphology changes. DSC was used to estimate stability and interaction among implant's components. The present work demonstrated the controlled and prolonged idebenone delivery from the PCL implants in an in vitro model. A consistent preclinical base was established, supporting the idea of idebenone-loaded PCL implants as a new strategy of long-term sustained intraocular delivery for the LHON treatment.

Topics: Animals; Chemistry, Pharmaceutical; Chickens; Chorioallantoic Membrane; Delayed-Action Preparations; Drug Carriers; Drug Delivery Systems; Drug Implants; Drug Stability; Optic Atrophy, Hereditary, Leber; Pilot Projects; Polyesters; Ubiquinone

Despite the growing interest and the potential benefits of idebenone as a repurposed drug for different orphan conditions, data regarding its monitoring are scarce. Our main goal was to report plasma idebenone values in a cohort of Friedreich's ataxia (FRDA) patients during a long-term follow-up. Taking advantage of this, we also assessed cardiological and neurological status together with idebenone values and genetic background.. Long-term follow-up retrospective study in 27 FRDA patients with a disease onset at the paediatric age treated with idebenone by compassionate use. Plasma idebenone was measured by HPLC with electrochemical detection.. Median plasma idebenone values increased when doses were increased, but apparently linearity was lost in the highest dose group. Marked intraindividual and interindividual differences were observed among patients. We did not find a consistent positive effect after analysis of paired data at the beginning and the end of the study. We only found a correlation between some cardiological measures and the duration of idebenone therapy at high doses, but with uncertain significance.. The large variations observed among the different individuals involved in this study should be considered for optimization of individual dosage regimens.

Topics: Adolescent; Antioxidants; Biological Variation, Individual; Biological Variation, Population; Child; Child, Preschool; Chromatography, High Pressure Liquid; Compassionate Use Trials; Drug Monitoring; Electrochemical Techniques; Female; Follow-Up Studies; Friedreich Ataxia; Humans; Male; Predictive Value of Tests; Retrospective Studies; Time Factors; Treatment Outcome; Ubiquinone; Young Adult

Atherosclerosis, a chronic disease of the arteries, results from pathological processes including the accumulation and aggregation of oxidized low-density lipoprotein (oxLDL) in the vessel walls, development of neointima, formation of a fibrous cap, and migration of immune cells to damaged vascular endothelium. Recent studies have shown that mitochondrial dysfunction is closely associated with the development and progression of atherosclerosis. Idebenone, a short-chain benzoquinone similar in structure to coenzyme Q10, can effectively clear oxygen free radicals as an electron carrier and antioxidant. In the present study, we aim to investigate weather idebenone protects against atherosclerosis in apolipoprotein E-deficient (apoE-/-) mice.. apoE-/- mice receiving a high-fat diet (HFD) were treated with idebenone for 16 weeks. A total of 60 mice were randomized into the following four groups: (1) HFD, (2) HFD and low-dose idebenone (100 mg/kg/d), (3) HFD and medium-dose idebenone (200 mg/kg/d), and (4) HFD and high-dose (400 mg/kg/d). Proteomic analysis was performed between the HFD and idebenone-high-dose group. Plaque analysis was carried out by histological and immunohistochemical staining. Western blot, TUNEL staining, and MitoSOX assays were performed in human umbilical vein endothelial cells (HUVECs) to investigate the SIRT3-SOD2-mtROS pathway.. Histological and morphological analysis demonstrated that idebenone significantly reduced plaque burden and plaque size. Idebenone treatment effectively stabilized the atherosclerotic plaques. In mice treated with idebenone, 351 up-regulated and 379 down-regulated proteins were found to be significantly altered in proteomic analysis. In particular, the expression of SIRT3, SOD2, and NLRP3 was significantly regulated in the idebenone treatment groups compared with the HFD group both in vivo and in vitro. We further confirmed that idebenone protected against endothelial cell damage and inhibited the production of mitochondrial reactive oxygen species (mtROS) in cholesterol-treated HUVECs.. We demonstrated that idebenone acted as a mitochondrial protective agent by inhibiting the activation of NLPR3 via the SIRT3-SOD2-mtROS pathway. Idebenone may be a promising therapy for patients with atherosclerosis by improving mitochondrial dysfunction and inhibiting oxidative stress.

Topics: Animals; Apolipoproteins E; Apoptosis; Atherosclerosis; Cell Survival; Human Umbilical Vein Endothelial Cells; Humans; Male; Mice; Mice, Transgenic; Mitochondria; Oxidative Stress; Proteomics; Random Allocation; Reactive Oxygen Species; Sirtuin 3; Superoxide Dismutase; Ubiquinone; Voltage-Sensitive Dye Imaging

Leber's hereditary optic neuropathy (LHON) is a mitochondrial neuropathy that causes acute vision loss. Idebenone, a short-chain ubiquinone analog that preserves mitochondrial function is thought to suppress disease progression in early-onset LHON patients. We investigated the effects of idebenone in Japanese LHON patients.. Prospective, interventional, non-comparative study in patients with definite LHON diagnosis, under trial registration number UMIN000017939.. Fifty-seven patients received 900 mg/day idebenone for 24 weeks. We measured baseline best-corrected visual acuity, visual fields, critical fusion frequency and retinal ganglion cell layer complex thickness; we assessed efficacy at 24 and 48 weeks, and safety throughout.. Patients were predominantly male (91.2%) and most had an mt.11778G>A mutation (94.7%). All patients tolerated idebenone therapy well. Data from the 51 mt.11778 patients were compared with their baseline data. At 48 weeks, significant improvement in best-corrected visual acuity was observed in 17 patients (33.3%). Furthermore, 25.5% of patients showed improvements in visual fields and 33.3% in critical fusion frequency. However, retinal ganglion cell layer complex thickness was significantly reduced. Among patients who started idebenone >1 year after disease onset, visual improvement was found in 12 (38.7%). Among patients who developed LHON before 19 years of age, visual improvement was found in 11 (42.3%).. Idebenone's potential and favorable safety profile were confirmed in Japanese LHON patients. However, this study had no placebo group; therefore, we need to undertake a prospective intervention study to further investigate the therapeutic effects of Idebenone in Japanese LHON patients.

Topics: Humans; Japan; Male; Optic Atrophy, Hereditary, Leber; Prospective Studies; Ubiquinone; Visual Acuity

Oxidative stress is considered one of the mechanisms responsible for neurodegenerative diseases, especially for Parkinson's disease. Since oxidative stress causes pathological changes in neuronal structures antioxidant compounds gained significant attention the last decades. Although several antioxidant compounds showed neuroprotective actions in Parkinson's disease models, only a few of them demonstrated protective effects against loss of striatal dopaminergic neurons. Idebenone is an analog of the well-known antioxidant compound coenzyme Q10 (CoQ10). Clinical safety of idebenone is well described, and due to its high antioxidant capacity currently used to treat Freidrich's ataxia and Alzheimer's disease. Like Parkinson's disease, these diseases are characterized by oxidative stress and impaired mitochondrial balance in neurons. However, knowledge about the effects of idebenone on Parkinson's disease is limited. Therefore, in this study we aimed to investigate and delineate the possible effects of idebenone in rotenone-induced Parkinson's disease models. Idebenone (200 mg/kg, p.o.) inhibited the decrease of striatal expression of NAD(P)H dehydrogenase[quinone]-1, which is an essential element for mitochondrial respiration. Idebenone decreased the striatal levels of the lipid peroxidation products and increased the expression of glutathione peroxidase-4 (GPx-4), which is primarily known for lipid peroxidation and ferroptosis. Furthermore, idebenone mitigated motor impairment and increased tyrosine hydroxylase-positive neuron survival. Together our results thus indicate that that idebenone has protective effects against a rotenone insult with pleiotropic actions on the cellular oxidative enzymes and lipid peroxidation.

Topics: Animals; Antioxidants; Brain; Dopaminergic Neurons; Lipid Peroxidation; Locomotion; Male; Neuroprotective Agents; Open Field Test; Parkinson Disease, Secondary; Rats, Sprague-Dawley; Rotenone; Ubiquinone

In September 2015, the first and so far only medication for treatment of Leber's hereditary optic neuropathy (LHON) was approved in the EU. The drug in question is idebenone (©Raxone) and has been given to all newly diagnosed patients of the University Eye Hospital Tuebingen since the approval of the drug. The aim of the study was to find out whether regular administration of the drug led to an improvement in vision. We retrospectively examined 2 cohorts of consecutive patients with newly occurred visual impairment and LHON diagnosis: One with the initial diagnosis made from January 2010 until April 2014 and a second from October 2015 until January 2020.. Retrospective, observational cohort study. All electronic medical files of newly diagnosed and genetically confirmed LHON patients of the University Eye Hospital Tuebingen from January 2010 until April 2014 (cohort 1) and October 2015 until January 2020 (cohort 2) with at least 12 months of follow-up examinations have been analyzed.. Five patients were included in the first and 7 patients in the second cohort. Patients of cohort 1 received no medication; patients of cohort 2, a daily dose of 900 mg idebenone. The primary visual acuity (VA) ranged between 0.03 and 0.5 in cohort 1 and did not improve during the observation period (median 60 months, range 23-87 months). The patients of cohort 2 have been observed for a median of 23 months (range 12-35 m). The primary VA ranged from 0.01 to 0.16. A recovery in one or both eyes with a final VA from 0.8 to 1.0 was experienced in 3 out of 7 patients. All patients showing a recovery of VA carried the m.11778G>A mutation.. The observed improvement in the treated cohort may be considered as a hint on the efficacy of idebenone in LHON. The time course of improvement suggests that idebenone should be given 1.5 years in newly diagnosed LHON cases.

Topics: DNA, Mitochondrial; Humans; Mutation; Optic Atrophy, Hereditary, Leber; Retrospective Studies; Ubiquinone

Topics: Humans; Japan; Optic Atrophy, Hereditary, Leber; Prospective Studies; Ubiquinone

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Congresses as Topic; Disease Models, Animal; Drug Evaluation, Preclinical; Drug Repositioning; Dysbiosis; Gastrointestinal Microbiome; Gene Expression Regulation; Humans; Lupus Erythematosus, Systemic; Metformin; Mice; RNA-Seq; Single-Cell Analysis; Ubiquinone; Videoconferencing

Succinate dehydrogenase (Complex II) plays a dual role in respiration by catalyzing the oxidation of succinate to fumarate in the mitochondrial Krebs cycle and transferring electrons from succinate to ubiquinone in the mitochondrial electron transport chain (ETC). Mutations in Complex II are associated with a number of pathologies. SDHD, one of the four subunits of Complex II, serves by anchoring the complex to the inner-membrane and transferring electrons from the complex to ubiquinone. Thus, modeling SDHD dysfunction could be a valuable tool for understanding its importance in metabolism and developing novel therapeutics, however no suitable models exist.. Via CRISPR/Cas9, we mutated SDHD in HEK293 cells and investigated the in vitro role of SDHD in metabolism. Compared to the parent HEK293, the knockout mutant HEK293ΔSDHD produced significantly less number of cells in culture. The mutant cells predictably had suppressed Complex II-mediated mitochondrial respiration, but also Complex I-mediated respiration. SDHD mutation also adversely affected glycolytic capacity and ATP synthesis. Mutant cells were more apoptotic and susceptible to necrosis. Treatment with the mitochondrial therapeutic idebenone partially improved oxygen consumption and growth of mutant cells.. Overall, our results suggest that SDHD is vital for growth and metabolism of mammalian cells, and that respiratory and growth defects can be partially restored with treatment of a ubiquinone analog. This is the first report to use CRISPR/Cas9 approach to construct a knockout SDHD cell line and evaluate the efficacy of an established mitochondrial therapeutic candidate to improve bioenergetic capacity.

Topics: Cell Proliferation; CRISPR-Cas Systems; Electron Transport Complex II; HEK293 Cells; Humans; Mitochondria; Mutation; Succinate Dehydrogenase; Ubiquinone

Idebenone (IDB) has demonstrated the potential to treat mitochondrial and neurodegenerative diseases, including Alzheimer's disease (AD). However, its therapeutic effects are compromised by poor compliance due to low bioavailability. The objective of this study is to fabricate IDB nanorods (IDBNRs) to improve oral bioavailability and increase concentrations in the brain in order to enhance therapeutic effects of IDB in the treatment of AD. IDBNRs showed desired sizes and rod-shaped morphologies. The release rate and the antioxidant activity of IDBNRs were improved relative to other delivery routes. The plasma and brain concentrations were enhanced due to rapid release into the systemic circulation. In behavioral tests, mice treated orally with IDBNRs showed amelioration of AD-induced impairment of learning and memory. Thus, because of improved efficiency of drug delivery, doses can be reduced, and the compliance and therapeutic experience of patients can be improved. IDBNRs may provide effective and convenient treatments for AD patients in the future.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Disease Models, Animal; Humans; Mice; Mice, Transgenic; Nanotubes; Neuroprotective Agents; Ubiquinone

Experimental models of maternal diabetes lead to the intrauterine programming of Gestational Diabetes Mellitus (GDM) in the offspring, together with an intrauterine proinflammatory environment, feto-placental metabolic alterations and fetal overgrowth. The aim of this work was to evaluate the effect of the mitochondrial antioxidant Idebenone given to F0 mild pregestational diabetic rats on the development of GDM in their F1 offspring and the intergenerational programming of a pro-oxidant/proinflammatory environment that affects the placentas of F2 fetuses. Control and mild pregestational diabetic female rats (F0) were mated with control males, and Idebenone or vehicle was administered to diabetic rats from day 1 of gestation to term. The F1 female offspring were mated with control males and maternal and fetal plasma samples were obtained for metabolic determinations at term. The F2 fetuses and placentas were weighed, and placental protein levels and peroxynitrite-induced damage (immunohistochemistry), mRNA levels (PCR), nitric oxide production (Griess reaction), and number of apoptotic cells (TUNEL) were evaluated. The F1 offspring of F0 diabetic rats (treated or not with Idebenone) developed GDM. The placentas of GDM rats showed a decrease in the mRNA levels of manganese superoxide dismutase and an increase in the production of nitric oxide, peroxynitrite-induced damage, and connective tissue growth factor levels, alterations that were prevented by the maternal Idebenone treatment in F0 rats. In conclusion, the maternal treatment with Idebenone in pregestational diabetic F0 rats ameliorates the pro-oxidant/proinflammatory environment that affects the placentas of F2 fetuses, although it does not prevent F1 rats from developing GDM.

Topics: Animals; Antioxidants; Diabetes Mellitus, Experimental; Diabetes, Gestational; Female; Fetal Macrosomia; Fetus; Male; Nitric Oxide; Placenta; Pregnancy; Pregnancy Proteins; Rats; Rats, Wistar; Ubiquinone

Shc expression rises in human nonalcoholic steatohepatitis (NASH) livers, and Shc-deficient mice are protected from NASH-thus Shc inhibition could be a novel therapeutic strategy for NASH. Idebenone was recently identified as the first small-molecule Shc inhibitor drug. We tested idebenone in the fibrotic methionine-choline deficient (MCD) diet and the metabolic fast food diet (FFD) mouse models of NASH. In the fibrotic MCD NASH model, idebenone reduced Shc expression and phosphorylation in peripheral blood mononuclear cells and Shc expression in the liver; decreased serum alanine aminotransferase and aspartate aminotransferase; and attenuated liver fibrosis as observed by quantitative polymerase chain reaction (qPCR) and hydroxyproline quantification. In the metabolic FFD model, idebenone administration improved insulin resistance, and reduced inflammation and fibrosis shown with qPCR, hydroxyproline measurement, and histology. Thus, idebenone ameliorates NASH in two mouse models. As an approved drug with a benign safety profile, Idebenone could be a reasonable human NASH therapy.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Choline Deficiency; Diet; Disease Models, Animal; Fast Foods; Leukocytes, Mononuclear; Liver; Liver Cirrhosis; Male; Methionine; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Phosphorylation; Protective Agents; Shc Signaling Adaptor Proteins; Signal Transduction; Therapeutics; Ubiquinone

Leber's hereditary optic neuropathy (LHON) is a rare inherited blindness caused by mutations in the mitochondrial DNA (mtDNA). The disorder is untreatable and tricky, as the existing chemotherapeutic agent Idebenone alleviates symptoms rather than overcoming the underlying cause. Although some studies have made progress on allotopic expression for LHON, in situ mitochondrial gene therapy remains challenging, which may simplify delivery procedures to be a promising therapeutic for LHON. LHON becomes more difficult to manage in the changed mitochondrial microenvironment, including increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential (MMP). Herein, a pathologically responsive mitochondrial gene delivery vector named [triphenylphosphine-terminated poly(sulfur-containing thioketal undecafluorohexylamine histamine) and Ide-terminated poly(sulfur-containing thioketal undecafluorohexylamine histamine)] (TISUH) is reported to facilitate commendable in situ mitochondrial gene therapy for LHON. TISUH directly targets diseased mitochondria via triphenylphosphine and fluorination addressing the decreasing MMP. In addition, TISUH can be disassembled by high mitochondrial ROS levels to release functional genes for enhancing gene transfection efficiency and fundamentally correcting genetic abnormalities. In both traditional and gene-mutation-induced LHON mouse models, TISUH-mediated gene therapy shows satisfactory curative effect through the sustained therapeutic protein expression in vivo. This work proposes a novel pathologically responsive in situ mitochondrial delivery platform and provides a promising approach for refractory LHON as well as other mtDNA mutated diseases treatments.

Topics: Animals; Disease Models, Animal; DNA; DNA, Mitochondrial; Electron Transport Complex I; Fluorescent Dyes; Genetic Therapy; Humans; Membrane Potential, Mitochondrial; Mice; Mice, Inbred BALB C; Mitochondria; Optic Atrophy, Hereditary, Leber; Polymers; Protein Subunits; Reactive Oxygen Species; Ubiquinone

A role for mitochondrial dysfunction has been proposed in the immune dysregulation and organ damage characteristic of systemic lupus erythematosus (SLE). Idebenone is a coenzyme Q10 synthetic quinone analog and an antioxidant that has been used in humans to treat diverse diseases in which mitochondrial function is impaired. This study was undertaken to assess whether idebenone ameliorates lupus in murine models.. Idebenone was administered orally to MRL/lpr mice at 2 different doses (1 gm/kg or 1.5 gm/kg idebenone-containing diet) for 8 weeks. At peak disease activity, clinical, immunologic, and metabolic parameters were analyzed and compared to those in untreated mice (n = 10 per treatment group). Results were confirmed in the lupus-prone NZM2328 mouse model.. In MRL/lpr mice, idebenone-treated mice showed a significant reduction in mortality incidence (P < 0.01 versus untreated mice), and the treatment attenuated several disease features, including glomerular inflammation and fibrosis (each P < 0.05 versus untreated mice), and improved renal function in association with decreased renal expression of interleukin-17A (IL-17A) and mature IL-18. Levels of splenic proinflammatory cytokines and inflammasome-related genes were significantly decreased (at least P < 0.05 and some with higher significance) in mice treated with idebenone, while no obvious drug toxicity was observed. Idebenone inhibited neutrophil extracellular trap formation in neutrophils from lupus-prone mice (P < 0.05) and human patients with SLE. Idebenone also improved mitochondrial metabolism (30% increase in basal respiration and ATP production), reduced the extent of heart lipid peroxidation (by one-half that of untreated mice), and significantly improved endothelium-dependent vasorelaxation (P < 0.001). NZM2328 mice exposed to idebenone also displayed improvements in renal and systemic inflammation, reducing the kidney pathology score (P < 0.05), IgG/C3 deposition (P < 0.05), and the gene expression of interferon, proinflammatory, and inflammasome-related genes (at least P < 0.05 and some with higher significance).. Idebenone ameliorates murine lupus disease activity and the severity of organ damage, supporting the hypothesis that agents that modulate mitochondrial biologic processes may have a therapeutic role in human SLE.

Topics: Animals; Antioxidants; Disease Models, Animal; Extracellular Traps; Inflammation; Interleukin-17; Interleukin-18; Kidney; Lupus Erythematosus, Systemic; Mice; Mice, Inbred MRL lpr; Mitochondria; Ubiquinone

Idebenone has recently been investigated as a drug therapy for Leber's hereditary optic neuropathy (LHON), a rare genetic mitochondrial disease that causes rapid and progressive bilateral vision loss. Although several studies have shown that idebenone can promote vision recovery in patients with LHON, the evidence for the efficacy of idebenone is still limited. Idebenone failed to demonstrate superiority over placebo in the primary end-points of the only published randomised, double-blind, placebo-controlled trial. There appears to be a patient-specific response to idebenone with high variability in therapeutic outcomes. A recent study suggested that the cytosolic enzyme NAD(P)H: quinone acceptor oxidoreductase (NQO1) is the major enzyme involved in the activation of idebenone, and the beneficial effects of idebenone are dependent on the expression of NQO1. Here, we confirm the NQO1-dependent activity of idebenone, but we also show, for the first time, that the cytotoxicity of idebenone is linked to cellular expression of NQO1. Upon idebenone administration, cells deficient in NQO1 show a marked decrease in viability in comparison to NQO1 expressing cells, with idebenone causing ROS production and deleterious effects on ATP levels and cell viability. In addition, our data highlights that only cells expressing NQO1 can significantly activate idebenone, indicating that other proposed metabolic activation pathways, such as complex II and glycerol-3-phosphate dehydrogenase, do not play a significant role in idebenone activation. Furthermore, we provide evidence of idebenone-induced toxicity in the retina ex-vivo, which can be explained by the variation of NQO1 expression between different cell types in the mouse retina. Idebenone mediated cell rescue in the rotenone ex vivo model also indicated that this drug has a narrow therapeutic window. These findings will help to guide the development of future therapies and drug delivery strategies including intra-ocular administration. The specific dependence of idebenone activity on NQO1 may also explain the variation in patient outcomes in clinical trials.

Topics: Animals; Antioxidants; Cell Death; Humans; Mice; NAD(P)H Dehydrogenase (Quinone); Retina; Ubiquinone

Oxidative stress is a key player of the inflammatory cascade responsible for the initiation of ulcerative colitis (UC). Although the short chain quinone idebenone is considered a potent antioxidant and a mitochondrial electron donor, emerging evidence suggests that idebenone also displays anti-inflammatory activity. This study evaluated the impact of idebenone in the widely used dextran sodium sulphate (DSS)-induced mouse model of acute colitis. Acute colitis was induced in C57BL/6J mice via continuous exposure to 2.5% DSS over 7 days. Idebenone was co-administered orally at a dose of 200 mg/kg body weight. Idebenone significantly prevented body weight loss and improved the disease activity index (DAI), colon length, and histopathological score. Consistent with its reported antioxidant function, idebenone significantly reduced the colonic levels of malondialdehyde (MDA) and nitric oxide (NO), and increased the expression of the redox factor NAD(P)H (nicotinamide adenine dinucleotide phosphate) dehydrogenase quinone-1 (NQO-1) in DSS-exposed mice. Immunohistochemistry revealed a significantly increased expression of tight junction proteins, which protect and maintain paracellular intestinal permeability. In support of an anti-inflammatory activity, idebenone significantly attenuated the elevated levels of pro-inflammatory cytokines in colon tissue. These results suggest that idebenone could represent a promising therapeutic strategy to interfere with disease pathology in UC by simultaneously inducing antioxidative and anti-inflammatory pathways.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Dextran Sulfate; Disease Models, Animal; Female; Gene Expression Regulation; Humans; Malondialdehyde; Mice; Mice, Inbred C57BL; NAD(P)H Dehydrogenase (Quinone); Nitric Oxide; Ubiquinone; Weight Loss

We previously documented that idebenone treatment in OPA1-Dominant Optic Atrophy (OPA1-DOA) led to some degrees of visual improvement in seven patients. We here present the results of a cohort study, which investigated the effect of off-label idebenone administration in a larger OPA1-DOA group compared with untreated patients. Inclusion criteria were: OPA1-DOA clinical and molecular diagnosis, baseline visual acuity (VA) greater than/equal to counting fingers and treatment duration greater than 7 months. We found a significant difference between the last visit and baseline VA in favor of stabilization/recovery in idebenone-treated as compared to untreated patients. This effect was retained after controlling for confounders.

Topics: Adolescent; Adult; Antioxidants; Cohort Studies; Female; GTP Phosphohydrolases; Humans; Male; Middle Aged; Off-Label Use; Optic Atrophy, Autosomal Dominant; Outcome Assessment, Health Care; Ubiquinone; Visual Acuity; Young Adult

Topics: DNA, Mitochondrial; Humans; Optic Atrophy, Hereditary, Leber; Ubiquinone

Cataract is the principal cause of blindness. The enzyme, aldose reductase (AR) is a key player in polyol pathway. Buildup of polyols and oxidative stress are the main causes of cataractogenesis. This study investigated the cytoprotective properties of esculetin and idebenone in galactose-induced cataract. Rats were partitioned into four groups each of ten rats. Control group was fed with normal diet; group 2 rats were fed with galactose diet (50%); groups 3, 4 rats were fed with galactose diet concurrently with either esculetin (50 mg/kg BW) or idebenone (100 mg/kg BW), for 20 days. The study revealed that esculetin and idebenone significantly reduced the elevated levels of Bax/Bcl-2 ratio, malondialdehyde, and DNA fragmentation and increased total antioxidant capacity level in lenses compared to the cataract-induced group. Only esculetin decreased AR, galactitol, and advanced glycated end products levels in lenses. Histopathological examinations supported the biochemical findings. Esculetin and idebenone may have chemopreventive effects for sugar cataract. PRACTICAL APPLICATIONS: Cataract is an age-related disease that might cause blindness in older adult people. Presently, no absolute pharmacological treatment is accessible for cataract. The use of natural products or their derivatives attract particular attention in modern medicines as they are believed to be safer with few or no side effects. Esculetin is a polyphenolic compound found in many medicinal plants. Idebenone is a synthetic analogue of coenzyme Q10. The current study is an approach to explore the anticataract effects of esculetin and idebenone in galactose-induced cataract in rats. Our study proved that both agents have anticataractogenic potentials due to their antioxidant and antiapoptotic properties.

Topics: Animals; Cataract; Galactose; Glutathione; Rats; Rats, Sprague-Dawley; Ubiquinone; Umbelliferones

Idebenone is a synthetic quinone that on reduction in cells can bypass mitochondrial Complex I defects by donating electrons to Complex III. The drug is used clinically to treat the Complex I disease Leber's hereditary optic neuropathy (LHON), but has been less successful in clinical trials for other neurodegenerative diseases. NAD(P)H:quinone oxidoreductase 1 (NQO1) appears to be the main intracellular enzyme catalyzing idebenone reduction. However, NQO1 is not universally expressed by cells of the brain. Using primary rat cortical cells pooled from both sexes, we tested the hypotheses that the level of endogenous NQO1 activity limits the ability of neurons, but not astrocytes, to use idebenone as an electron donor to support mitochondrial respiration. We then tested the prediction that NQO1 induction by pharmacological activation of the transcription factor nuclear erythroid 2-related factor 2 (Nrf2) enables idebenone to bypass Complex I in cells with poor NQO1 expression. We found that idebenone stimulated respiration by astrocytes but reduced the respiratory capacity of neurons. Importantly, idebenone supported mitochondrial oxygen consumption in the presence of a Complex I inhibitor in astrocytes but not neurons, and this ability was reversed by inhibiting NQO1. Conversely, recombinant NQO1 delivery to neurons prevented respiratory impairment and conferred Complex I bypass activity. Nrf2 activators failed to increase NQO1 in neurons, but carnosic acid induced NQO1 in COS-7 cells that expressed little endogenous enzyme. Carnosic acid-idebenone combination treatment promoted NQO1-dependent Complex I bypass activity in these cells. Thus, combination drug strategies targeting NQO1 may promote the repurposing of idebenone for additional disorders.

Topics: Animals; Animals, Newborn; Antioxidants; Astrocytes; Cell Respiration; Cells, Cultured; Chlorocebus aethiops; COS Cells; Dose-Response Relationship, Drug; Enzyme Activation; Female; Male; Mitochondria; NAD(P)H Dehydrogenase (Quinone); Rats; Rats, Sprague-Dawley; Ubiquinone

We aimed to evaluate the current practice patterns of neuro-ophthalmologists in diagnosis and management of three optic neuropathies using a national survey in South Korea and to further compare the practices of neuro-ophthalmologists divided into junior and senior groups based on their clinical practice experience.. An anonymous, 15-question survey on the diagnosis and treatment of traumatic optic neuropathy (TON), nonarteritic anterior ischemic optic neuropathy (NAION), and Leber's hereditary optic neuropathy (LHON) was sent to all neuro-ophthalmologists registered with the Korean Neuro-ophthalmology Society. The questions addressed physician's practice duration as neuro-ophthalmologist, choices of MRI scans and laboratory tests for the diagnosis in suspected optic neuropathy, clinical experiences with steroids (e.g., side effects), and choices of treatment modalities and reason in in each optic neuropathy. All participants were classified into senior (≥ 10 years) and junior (< 10 years) groups.. A total of 63 responders (response rate 78.8%) answered the questionnaire. All responders performed the basic blood tests and brain imaging for evaluating optic neuropathy. Observation was the most preferred option for TON (47.6%) and NAION (63.5%). Steroid use was the second most preferred, and the most selected indication of steroid was "when the patient wants" (58.7%) for TON and "severe visual loss or last eye" (66%) for NAION. The most preferred treatment for LHON was "prescribing idebenone" (69.7%) with a dose of 900 mg/day (63.8%). Forty-nine respondents (77.8%) experienced side effects of steroids. There was no significant difference between the senior and junior groups in all questionnaire answers (all p > 0.05).. Optic neuropathies are being managed similarly by the two groups in South Korea, and many of them still use steroids. We provided reliable reasons for our results compared with other countries.

Topics: Adult; Antioxidants; Dose-Response Relationship, Drug; Glucocorticoids; Humans; Incidence; Magnetic Resonance Imaging; Male; Optic Nerve; Optic Nerve Diseases; Republic of Korea; Surveys and Questionnaires; Treatment Outcome; Ubiquinone; Visual Acuity

Idebenone is a well-appreciated mitochondrial protectant while the mechanisms underlying the neuroprotection in cerebral ischemia and reperfusion (I/R) remain elusive. It has been manifested NLRP3 inflammasom activation contributed to I/R induced damage. It raises questions how exactly NLRP3 inflammasom was activated in microglia and neuron and whether idebenone reverses the process in I/R.. I/R rat model was utilized and BV2, primary microglia and PC12 cells were subjected to oxygen-glucose deprivation (OGD). Then, western-blotting, q-PCR, immunofluorescence staining, ELISA, flow cytometry and immunoprecipitation analysis were performed.. We found ROS-NLRP3 singaling was activated in BV2 cells at OGD/R 24 h. Importantly, microglial NLRP3 activation was essential for NLRP3 activation in PC12 cells under microglial-neuronal co-culture circumstance, which has been confirmed to induced neuronal apoptosis. Further, we found mitochondrial dysfunction in OGD/R led to mt-DNA translocation as well as generation of mt-ROS, resulting cytosolic accumulation of oxidized mt-DNA. Ultimately, oxidized mt-DNA binding to NLRP3 contributed to further activation of NLRP3 and dramatically augmented inflammation in BV2 and PC12 cells. Furthermore, idebenone treatment inhibited the process, thus suppressing the NLRP3-mediated inflammatory injury after OGD/R. In vivo, NLRP3 was activated in microglia of I/R rats and inhibition of NLRP3 was observed in idebenone treatment group, which had less neurological deficit and less infarct volume.. Our data revealed the anti-inflammatory effects of idebenone via suppressing activation of NLRP3 and ameliorating NLRP3-mediating damage in I/R, which may provide new insight in therapeutic strategy for ischemic stroke.

Topics: Animals; Animals, Newborn; Brain Ischemia; Cells, Cultured; Encephalitis; Inflammasomes; Male; Mice; Mice, Inbred C57BL; Neuroprotection; NLR Family, Pyrin Domain-Containing 3 Protein; PC12 Cells; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Stroke; Ubiquinone

Mitochondrial dysfunction has been repeatedly identified to be hallmark brain pathology underlying neuronal stress in Alzheimer's disease. As a result, mitochondrial medicine for the treatment of Alzheimer's disease has received increasing recognition. Idebenone (IDB) is a synthetic analog of Coenzyme Q10 (CoQ10) carrying antioxidizing property. Previous clinical trials reported a conflicting disease-modifying effect of IDB on Alzheimer's disease patients. However, whether IDB is preventive against amyloid beta (Aβ)-induced mitochondrial and neuronal stress has not been comprehensively investigated. In this study, we adopted an in-vitro setting by using primary cultured cortical neurons for the test. Neurons were pretreated with IDB prior to Aβ exposure. IDB pretreatment significant prevented neurons from Aβ-induced collapse of mitochondrial bioenergetics and perturbations of the protein kinase A (PKA)/cAMP response element-binding protein (CREB) signaling. Importantly, the treatment of IDB alone demonstrated an indiscernible side effect on the measured mitochondrial function, PKA/CREB signaling and neuronal viability. Therefore, our findings in together show a preventive effect of IDB against Aβ-mediated mitochondrial and neuronal injury. The use of IDB may hold potential to reduce the risk of Alzheimer's disease as a preventive strategy.

Topics: Amyloid beta-Peptides; Animals; Animals, Newborn; Antioxidants; Cells, Cultured; Cerebral Cortex; Dose-Response Relationship, Drug; Mice; Mice, Inbred C57BL; Mitochondria; Neuroprotective Agents; Peptide Fragments; Ubiquinone

There has been little innovation in identifying novel insulin sensitizers. Metformin, developed in the 1920s, is still used first for most Type 2 diabetes patients. Mice with genetic reduction of p52Shc protein have improved insulin sensitivity and glucose tolerance. By high-throughput screening, idebenone was isolated as the first small molecule 'Shc Blocker'. Idebenone blocks p52Shc's access to Insulin Receptor to increase insulin sensitivity. In this work the avidity of 34 novel idebenone analogs and 3 metabolites to bind p52Shc, and to block the interaction of p52Shc with the Insulin receptor was tested. Our hypothesis was that if an idebenone analog bound and blocked p52Shc's access to insulin receptor better than idebenone, it should be a more effective insulin sensitizing agent than idebenone itself. Of 34 analogs tested, only 2 both bound p52Shc more tightly and/or blocked the p52Shc-Insulin Receptor interaction more effectively than idebenone. Of those 2 only idebenone analog #11 was a superior insulin sensitizer to idebenone. Also, the long-lasting insulin-sensitizing potency of idebenone in rodents over many hours had been puzzling, as the parent molecule degrades to metabolites within 1 h. We observed that two of the idebenone's three metabolites are insulin sensitizing almost as potently as idebenone itself, explaining the persistent insulin sensitization of this rapidly metabolized molecule. These results help to identify key SAR = structure-activity relationship requirements for more potent small molecule Shc inhibitors as Shc-targeted insulin sensitizers for type 2 diabetes.

Topics: Animals; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Insulin; Insulin Resistance; Mice; Mice, Inbred C57BL; Rats; Rats, Sprague-Dawley; Receptor, Insulin; Src Homology 2 Domain-Containing, Transforming Protein 1; Structure-Activity Relationship; Ubiquinone

Homeostatic control of neuronal excitability by modulation of synaptic inhibition (I) and excitation (E) of the principal neurons is important during brain maturation. The fundamental features of in-utero brain development, including local synaptic E-I ratio and bioenergetics, can be modeled by cerebral organoids (CO) that have exhibited highly regular nested oscillatory network events. Therefore, we evaluated a 'Phase Zero' clinical study platform combining broadband Vis/near-infrared(NIR) spectroscopy and electrophysiology with studying E-I ratio based on the spectral exponent of local field potentials and bioenergetics based on the activity of mitochondrial Cytochrome-C Oxidase (CCO). We found a significant effect of the age of the healthy controls iPSC CO from 23 days to 3 months on the CCO activity (chi-square (2, N = 10) = 20, p = 4.5400e-05), and spectral exponent between 30-50 Hz (chi-square (2, N = 16) = 13.88, p = 0.001). Also, a significant effect of drugs, choline (CHO), idebenone (IDB), R-alpha-lipoic acid plus acetyl-L-carnitine (LCLA), was found on the CCO activity (chi-square (3, N = 10) = 25.44, p = 1.2492e-05), spectral exponent between 1 and 20 Hz (chi-square (3, N = 16) = 43.5, p = 1.9273e-09) and 30-50 Hz (chi-square (3, N = 16) = 23.47, p = 3.2148e-05) in 34 days old CO from schizophrenia (SCZ) patients iPSC. We present the feasibility of a multimodal approach, combining electrophysiology and broadband Vis-NIR spectroscopy, to monitor neurodevelopment in brain organoid models that can complement traditional drug design approaches to test clinically meaningful hypotheses.

Topics: Acetylcarnitine; Brain; Case-Control Studies; Cell Line; Choline; Electron Transport Complex IV; Electrophysiology; Female; Humans; Induced Pluripotent Stem Cells; Male; Mitochondria; Organoids; Proof of Concept Study; Schizophrenia; Spectroscopy, Near-Infrared; Thioctic Acid; Ubiquinone

Topics: Adolescent; Compassionate Use Trials; Female; Friedreich Ataxia; Humans; Insulin-Like Growth Factor I; Ubiquinone; Vitamin E

The resistance of tumor cells to anticancer drugs has become one of the principal causes of the failure in clinical chemotherapy. To overcome this issue, developing feasible drug delivery systems for effective cancer therapy is urgently needed. In this work, we construct an amphiphilic drug self-delivery system consisting of Taxol and tyroservatide (YSV) to overcome drug resistance. The carrier-free supramolecular hydrogel composed of nanofibers is formed by the involved ester bond self-hydrolysis process, which has high drug loading efficiency and facilitates the delivery of both the hydrophobic Taxol and hydrophilic YSV. Because of the dual inhibitory function of YSV on histone deacetylase and P-glycoprotein, an improved combinational anticancer effect of the molecule against drug-resistant tumor cells in vitro is achieved. Furthermore, the designed drug self-delivery system exhibited enhanced antitumor efficiency and favorable biocompatibility in vivo when administered by tail vein injection. Our study provides a new strategy for fabricating a carrier-free supramolecular hydrogel to overcome drug resistance, which might open up an alternative avenue for the tumor combinational therapy.

Topics: Animals; ATP Binding Cassette Transporter, Subfamily B, Member 1; Drug Resistance, Neoplasm; HeLa Cells; Humans; Hydrogels; Mice; Mice, Inbred BALB C; Mice, Nude; Nanofibers; Neoplasm Proteins; Neoplasms, Experimental; Oligopeptides; Ubiquinone; Xenograft Model Antitumor Assays

Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease characterized by a subacute and progressive impairment and subsequent degeneration of retinal ganglion cells (RGCs). In most cases, it results in optic nerve atrophy and permanently reduced visual acuity (VA). Idebenone has recently been approved in Europe for treating LHON. However, published clinical data has only focused on efficacy in patients within the first years after disease onset. The present study is the first to evaluate possible effects of idebenone treatment in patients with LHON when initiated after more than 5 years from disease onset.. Oral treatment with idebenone 300 mg tid was started in seven patients 5 to 51 years after LHON onset. All patients had genetically confirmed primary LHON mutations (m11778G>A, m14484T>C, and m13051G>A). Visual function of all fourteen eyes was tested every 3 months using logarithmic reading charts and automated static threshold perimetry. The obtained clinical data were analyzed retrospectively using a multivariate analysis for VA and the Wilcoxon signed-rank test for visual field data.. Before treatment, VA was 0.78 ± 0.38 logMAR (range 0.24 to 1.50 logMAR). During the first year of therapy, VA improved significantly by an average of - 0.20 ± 0.10 logMAR or 10 ± 5 ETDRS letters (P = 0.002; VA range 0.06 to 1.30 logMAR). Seven of fourteen eyes showed an improvement of 2 or more lines. Visual field mean deviation increased from - 8.02 ± 6.11 to - 6.48 ± 5.26 dB after 12 months, but this change was not statistically significant (P = 0.056).. The increase in VA of patients who have had LHON for more than 5 years observed soon after start of treatment may not constitute a coincidental spontaneous recovery. We hypothesize that the treatment response in chronic LHON was the result of a reactivated signal transduction in surviving dysfunctional RGCs. The results of this study indicate a beneficial effect of idebenone on improvement of visual function in LHON patients with established optic atrophy.

Topics: Adult; Aged; Antioxidants; Chronic Disease; Follow-Up Studies; Forecasting; Humans; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Retinal Ganglion Cells; Retrospective Studies; Tomography, Optical Coherence; Treatment Outcome; Ubiquinone; Visual Acuity; Visual Fields; Young Adult

The present study was designed to test the effect of different levels of idebenone, a potent antioxidant on the quality of ram semen at post thaw. Eighteen (18) ejaculates were collected and extended with tris extender supplemented with no antioxidant (CON), with 2 μM idebenone (Id2), 5 μM idebenone (Id5), 7.5 μM idebenone (Id7.5) and 10 μM idebenone (Id10). The sperm quality was determined in terms of percent sperm motility, live sperm percentage, percent hypoosmotic swelling test (HOST) positive spermatozoa and percent intact acrosome (PIA). Moreover, malondialdehyde (MDA) level, an end product of lipid peroxidation (LPO) was also measured at post thaw both in seminal plasma and sperm cell. At post thaw, the percent sperm motility was significantly higher (p < 0.05) for Id10 as compared to Id2, Id5, Id7.5 and control. The live sperm percentage was non-significantly (p > 0.05) higher for Id10 as compared to control, Id5 and Id7.5 but significantly higher than Id2. The percent HOST positive spermatozoa was significantly higher (p < 0.05) for Id10 than control, Id2 and Id5. The MDA level in seminal plasma was significantly lower (p < 0.05) for Id10 than control and Id2. The MDA level in spermatozoa did show similar trend as in seminal plasma. Further, all the sperm parameters at all idebenone levels declined significantly from pre freeze to post thaw. In conclusion, idebenone at 10 μM level improved post thaw sperm quality by mitigating peroxidative stress, hence could be considered as a promising antioxidant additive for cryopreservation of ram semen.

Topics: Acrosome; Animals; Antioxidants; Cryopreservation; Cryoprotective Agents; Freezing; Humans; Lipid Peroxidation; Male; Malondialdehyde; Oxidative Stress; Semen; Semen Analysis; Semen Preservation; Sheep; Sperm Motility; Spermatozoa; Ubiquinone

Topics: Animals; Inflammation; Mice; Mitochondria; Ubiquinone

The current study was designed to investigate the effect of idebenone (Id), an antioxidant on ram semen quality. Semen samples were collected, pooled and diluted in a Tris-based extender supplemented with 0, 1, 2, 4 and 8 µM idebenone. Computer-assisted sperm analysis was used to evaluate spermatozoa kinematics. Sperm viability and membrane functionality were assessed respectively, by eosin-nigrosin staining and HOS test. Biochemical assays were carried out to measure different metabolites in spermatozoa and medium at 0, 24, 48 and 72 hr. Total and forward progressive motility were greater in 1, 2 and 4 µM idebenone treated groups compared to control at 24, 48 and 72 hr time points (p < 0.05). Semen supplementation with Id significantly increased viability and functionality of spermatozoa membrane during storage (p < 0.05). Lower amounts of lipid hydroperoxides in medium and spermatozoa were observed in Id-treated groups compared to control one at 24 and 48 hr of storage (p < 0.05). Medium and spermatozoa amounts of malondialdehyde and nitric oxide were less in Id 4 µM group compared to the control at 72 hr (p < 0.05). Total antioxidant capacity values and superoxide dismutase activity of spermatozoa and medium were greater in 2 and 4 µM idebenone treated groups in comparison with the control at 72 hr (p < 0.05). Results of the current study indicated that ram semen supplementation with Id at 4 µM level improved quality by ameliorating nitrosative and peroxidative stress, hence could be considered as an antioxidant additive during storage at 4°C.

Topics: Animals; Antioxidants; Cold Temperature; Male; Semen; Semen Analysis; Semen Preservation; Sheep; Specimen Handling; Spermatozoa; Time Factors; Ubiquinone

Topics: Diabetes Mellitus, Type 2; Humans; Hypoglycemic Agents; Insulin Resistance; Precision Medicine; Src Homology 2 Domain-Containing, Transforming Protein 1; Ubiquinone

Topics: Antineoplastic Agents; Apoptosis; Caspase 3; Cell Line, Tumor; Drug Screening Assays, Antitumor; Glioblastoma; Humans; Neoplasm Proteins; Ubiquinone

Leber's Hereditary Optic Neuropathy (LHON) causes a rapid and severe decrease in visual acuity. Raxone. Retrospective study of the efficacy of Raxone. Seventeen patients, three women and 14 men, mean age 34.2 years, naive to treatment with Raxone. The results confirm the trend of Raxone

Topics: Adolescent; Adult; Disease Progression; Female; Humans; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Paris; Retrospective Studies; Treatment Outcome; Ubiquinone; Visual Acuity; Young Adult

Topics: Aged; Antioxidants; Electron Transport Complex I; Humans; Late Onset Disorders; Male; Muscular Diseases; Mutation, Missense; Quadriceps Muscle; Ubiquinone

Topics: Consensus; DNA, Mitochondrial; Humans; Optic Atrophy, Hereditary, Leber; Point Mutation; Ubiquinone

In recent years, stem cell research has continued to benefit from its crossover with chemistry, particularly the investigation of small molecular drugs modulating specific targets to regulate stem cell fate. Idebenone (IDB) is a yellow crystalline powder that is used in the treatment of chronic cerebrovascular diseases. The objective of the present study was to examine whether IDB had an influence on bone marrow‑derived mesenchymal stem cells (BMSCs) extracted from the bone marrow of Sprague‑Dawley rats. The effects of IDB on cell proliferation, cell cloning and migration were investigated. Cell cycle, apoptosis, DAPI nuclear staining and senescence‑associated β‑galactosidase (SA‑β‑gal) staining were also examined. The results revealed that IDB at suitable concentrations enhanced cell cloning capacity, promoted the proliferation of BMSCs, delayed cellular senescence, and inhibited cell apoptosis and migration. Western blot analysis indicated that IDB increased the expression of B‑cell lymphoma 2 (Bcl‑2), signal transducer and activator of transcription‑3, Nanog, octamer‑binding transcription factor 4, E‑cadherin, proliferating cell nuclear antigen, cyclinD1 and cyclinD3, and decreased the expression of Bcl‑2‑associated X protein, cleaved caspase‑3, N‑cadherin, vimentin and α‑smooth muscle actin. In conclusion, these experiments confirmed that IDB in low doses had no toxic effect and may exert protective effects on BMSCs.

Topics: Animals; Apoptosis; Cell Cycle; Cell Differentiation; Cell Movement; Cell Proliferation; Cells, Cultured; Cellular Senescence; Colony-Forming Units Assay; Mesenchymal Stem Cells; Rats; Ubiquinone

Mitochondrial diseases are a group of devastating disorders for which there is no transformative cure. The majority of therapies for mitochondrial disease-approved, previously tested, or currently in development-are small molecules. The implementation of better cell-based models of mitochondrial disease can accelerate and improve the accuracy of small molecule drug discovery. The objective of this study is to evaluate the use of patient-derived lymphoblastoid cell lines for small molecule research in mitochondrial disease.. Five lymphoblastoid cell lines derived from mitochondrial disease patients harboring point mutations in mtND1, mtND4, or mtATP6 were characterized in two high throughput assays assessing mitochondrial function. In a pilot "clinical trial in a dish" experiment, the efficacy of idebenone-an approved therapy for mitochondrial disease-on the lymphoblastoid cell lines was tested. Idebenone increased the basal respiration of all lymphoblastoid cell lines except those harboring the 8993T>G point mutation in mtATP6. Our results posit lymphoblastoid cell lines as a strong model for mitochondrial disease research with small molecules and have implications for the clinical efficacy of idebenone.

Topics: Adult; Cell Line; Child; Child, Preschool; DNA, Mitochondrial; Drug Discovery; Female; Humans; Lymphocytes; Male; Mitochondrial Diseases; Oxygen Consumption; Point Mutation; Small Molecule Libraries; Ubiquinone; Young Adult

Idebenone is a hydrophilic short-chain coenzyme (Co) Q analogue, which has been used as a potential bypass of defective complex I in both Leber Hereditary Optic Neuropathy and OPA1-dependent Dominant Optic Atrophy. Based on its potential antioxidant effects, it has also been tested in degenerative disorders such as Friedreich's ataxia, Huntington's and Alzheimer's diseases. Idebenone is rapidly modified but the biological effects of its metabolites have been characterized only partially. Here we have studied the effects of quinones generated during in vivo metabolism of idebenone with specific emphasis on 6-(9-carboxynonyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (QS10). QS10 partially restored respiration in cells deficient of complex I or of CoQ without inducing the mitochondrial permeability transition, a detrimental effect of idebenone that may offset its potential benefits [Giorgio et al. (2012) Biochim. Biophys. Acta 1817: 363-369]. Remarkably, respiration was largely rotenone-insensitive in complex I deficient cells and rotenone-sensitive in CoQ deficient cells. These findings indicate that, like idebenone, QS10 can provide a bypass to defective complex I; and that, unlike idebenone, QS10 can partially replace endogenous CoQ. In zebrafish (Danio rerio) treated with rotenone, QS10 was more effective than idebenone in allowing partial recovery of respiration (to 40% and 20% of the basal respiration of untreated embryos, respectively) and allowing zebrafish survival (80% surviving embryos at 60 h post-fertilization, a time point at which all rotenone-treated embryos otherwise died). We conclude that QS10 is potentially more active than idebenone in the treatment of diseases caused by complex I defects, and that it could also be used in CoQ deficiencies of genetic and acquired origin.

Topics: Adenosine Triphosphate; Animals; Antioxidants; Ataxia; Cell Respiration; Cells, Cultured; Electron Transport; Electron Transport Complex I; Embryo, Nonmammalian; Mice; Mitochondria, Liver; Mitochondrial Diseases; Muscle Weakness; Ubiquinone; Zebrafish

Can maternal treatments with idebenone, a structural analogue of coenzyme Q10, prevent alterations on markers of proinflammatory-prooxidant processes, on the expression of genes involved in mitochondrial biogenesis and function, and on the apoptotic rate in embryos from mild diabetic rats?. A mild diabetic rat model was induced by neonatal-streptozotocin administration (90 mg/kg subcutaneously). Female diabetic rats and controls were mated with healthy males. From day 1 of pregnancy, control and diabetic rats were orally treated with idebenone (100 mg/kg daily). On day 10.5 of gestation, the embryos were explanted and prepared for immunohistochemical studies, for the evaluation of gene expression by reverse transcription polymerase chain reaction and for TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end-labelling assay analysis.. Embryos from mild diabetic rats showed increased levels of nitrated proteins, 4-hydroxynonenal and matrix metalloproteinase 9, which were prevented by idebenone administration. We also found a decreased embryonic expression of cytochrome c oxidase and reduced mRNA levels of peroxisome proliferator activated receptor-γ coactivator-1-α and nuclear respiratory factor-1, both of which were prevented by idebenone administration to the diabetic pregnant rats. Embryos from mild diabetic rats also showed an increased apoptotic rate, which was diminished by idebenone treatment.. Maternal idebenone treatment ameliorates altered parameters related to the prooxidant-proinflammatory environment found in embryos from mild diabetic rats, suggesting a putative treatment to prevent diabetes-induced embryo alterations.

Topics: Animals; Antioxidants; Apoptosis; Diabetes Mellitus, Experimental; Electron Transport Complex IV; Embryo, Mammalian; Embryonic Development; Female; Nuclear Respiratory Factor 1; Organogenesis; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Rats; Rats, Wistar; RNA, Messenger; Ubiquinone

The diagnosis of acute optic neuropathy is made clinically. In young patients demyelinating optic neuritis is the most common cause. However, other autoimmune diseases, infections and other non-inflammatory conditions may also cause inflammation. Careful clinical workup is necessary to establish the correct diagnosis and treatment. We describe the clinical approach to a case of acute optic neuropathy with several atypical features. The same case was published in the Journal of Neuro-Ophthalmology.. A male teenager developed acute and painless bilateral visual loss. Fundoscopy revealed optic disc hypaeremia with telangiectasia. Magnetic resonance imaging demonstrated contrast enhancement of the optic nerves and chiasm without evidence of demyelinating disease. There was no visual improvement after methylprednisolone treatment. Genetic analysis for the 3 common Leber hereditary optic neuropathy (LHON) mutations was negative. However, idebenone treatment was followed by a marked improvement in visual function. Whole mitochondrial genome sequencing eventually detected a rare LHON mutation.. There are many different causes of acute optic neuropathy. Making the correct diagnosis is important, as clinical management differs. Idebenone is now a treatment option for LHON. Whole mitochondrial genome sequencing is sometimes necessary to confirm the diagnosis.

Topics: Adolescent; Antioxidants; Humans; Male; Ophthalmoscopy; Optic Atrophy, Hereditary, Leber; Point Mutation; Treatment Outcome; Ubiquinone; Vision Disorders; Visual Field Tests

Current peroxisome proliferator-activated receptor (PPAR)-targeted drugs, such as the PPARγ-directed diabetes drug rosiglitazone, are associated with undesirable side effects due to robust agonist activity in non-target tissues. To find new PPAR ligands with fewer toxic effects, we generated transgenic zebrafish that can be screened in high throughput for new tissue-selective PPAR partial agonists. A structural analog of coenzyme Q

Topics: 3T3-L1 Cells; Animals; Animals, Genetically Modified; Benzoquinones; Drug Evaluation, Preclinical; HEK293 Cells; Humans; Ligands; Lipid Metabolism; Liver; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; PPAR alpha; PPAR gamma; Ubiquinone; Zebrafish

Nephrotic syndrome (NS), a frequent chronic kidney disease in children and young adults, is the most common phenotype associated with primary coenzyme Q

Topics: Alkyl and Aryl Transferases; Animals; Antioxidants; Ataxia; Disease Models, Animal; HeLa Cells; Humans; Hydrogen Sulfide; Kidney; Metabolic Networks and Pathways; Mice; Mice, Transgenic; Mitochondria; Mitochondrial Diseases; Muscle Weakness; Nephrotic Syndrome; Oxidation-Reduction; Oxidative Stress; Oxidoreductases Acting on Sulfur Group Donors; Reactive Oxygen Species; Ubiquinone

When insulin binds insulin receptor, IRS1 signaling is stimulated to trigger the maximal insulin response. p52Shc protein competes directly with IRS1, thus damping and diverting maximal insulin response. Genetic reduction of p52Shc minimizes competition with IRS1, and improves insulin signaling and glucose control in mice, and improves pathophysiological consequences of hyperglycemia. Given the multiple benefits of Shc reduction in vivo, we investigated whether any of 1680 drugs used in humans may function as Shc inhibitors, and thus potentially serve as novel anti-diabetics. Of the 1680, 30 insulin sensitizers were identified by screening in vitro, and of these 30 we demonstrated that 7 bound Shc protein. Of the 7 drugs, idebenone dose-dependently bound Shc protein in the 50-100 nM range, and induced insulin sensitivity and cytoprotection in this same 100 nM range that clinically dosed idebenone reaches in human plasma. By contrast we observe mitochondrial effects of idebenone in the 5,000 nM range that are not reached in human dosing. Multiple assays of target engagement demonstrate that idebenone physically interacts with Shc protein. Idebenone sensitizes mice to insulin in two different mouse models of prediabetes. Genetic depletion of idebenone's target eliminates idebenone's ability to insulin-sensitize in vivo. Thus, idebenone is the first-in-class member of a novel category of insulin-sensitizing and cytoprotective agents, the Shc inhibitors. Idebenone is an approved drug and could be considered for other indications such as type 2 diabetes and fatty liver disease, in which insulin resistance occurs.

Topics: Animals; Cell Line; Cytoprotection; Diabetes Mellitus, Experimental; Drug Repositioning; Female; High-Throughput Screening Assays; Humans; Hypoglycemic Agents; Insulin; Insulin Resistance; Male; Mice, Inbred C57BL; Mice, Knockout; Molecular Docking Simulation; Receptor, Insulin; Src Homology 2 Domain-Containing, Transforming Protein 1; Ubiquinone

A 28-year-old Caucasian man developed sudden painless vision loss in the right eye. He was diagnosed with optic neuritis. MRI showed white matter lesions consistent with multiple sclerosis (MS), but no optic nerve enhancement. Eight months later, the left eye was affected in the same manner. Examination showed right optic atrophy and apparent left optic disc swelling. Workup revealed positive Lyme IgG. Differential diagnosis included optic neuritis and Lyme optic neuropathy, and he was treated with intravenous steroids, intravenous immunoglobulin, plasmapheresis and intravenous ceftriaxone without improvement. Neuro-ophthalmology consultation led to identification of pseudo-optic disc oedema, and Leber's hereditary optic neuropathy (LHON) was suspected and confirmed by genetic testing. LHON may occur in association with MS, and should be considered in patients with MS with vision loss atypical for optic neuritis. This is especially important as new treatments for LHON (including gene therapy) are currently undergoing clinical trials.

Topics: Adult; Antioxidants; Diagnosis, Differential; Diagnostic Errors; Humans; Lyme Disease; Magnetic Resonance Imaging; Male; Multiple Sclerosis; Optic Atrophy, Hereditary, Leber; Optic Neuritis; Ubiquinone; Vision, Low; White Matter

Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease that typically causes bilateral blindness in young men. It is characterized by as yet undisclosed genetic and environmental factors affecting the incomplete penetrance.. We identified 27 LHON subjects who possess heteroplasmic primary LHON mutations. Mitochondrial DNA (mtDNA) copy number was evaluated.. The presence of centrocecal scotoma, an edematous, hyperemic optic nerve head, and vascular tortuosity, as well as telangiectasia was recognized in affected subjects. We found higher cellular mtDNA content in peripheral blood cells of unaffected heteroplasmic mutation carriers with respect to the affected.. The increase of cellular mtDNA content prevents complete loss of vision despite the presence of a heteroplasmic state of LHON primary mutation, suggesting that it is a key factor responsible for penetrance of LHON.

Topics: Antioxidants; Blindness; DNA Copy Number Variations; DNA, Mitochondrial; Female; Genes, Mitochondrial; Humans; Male; Mitochondria; Mitochondrial Diseases; Mutation; Optic Atrophy, Hereditary, Leber; Pedigree; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Ubiquinone; Visual Acuity

Idebenone (IDE) has been proposed for the treatment of neurodegenerative diseases involving mitochondria dysfunctions. Unfortunately, to date, IDE therapeutic treatments have not been as successful as expected. To improve IDE efficacy, in this work we describe a two-step approach: (1) synthesis of IDE ester derivatives by covalent linking IDE to other two antioxidants, trolox (IDETRL) and lipoic acid (IDELIP), to obtain a synergic effect; (2) loading of IDE, IDETRL, or IDELIP into solid lipid nanoparticles (SLN) to improve IDE and its esters' water solubility while increasing and prolonging their antioxidant activity. IDE and its derivatives loaded SLN showed good physico-chemical and technological properties (spherical shape, mean particle sizes 23-25 nm, single peak in the size distribution, ζ potential values -1.76/-2.89 mV, and good stability at room temperature). In vitro antioxidant activity of these SLN was evaluated in comparison with free drugs by means of oxygen radical absorbance capacity (ORAC) test. IDETRL and IDELIP showed a greater antioxidant activity than IDE and encapsulation of IDE and its derivatives into SLN was able to prolong their antioxidant activity. These results suggest that loading IDETRL and IDELIP into SLN could be a useful strategy to improve IDE efficacy.

Topics: Antioxidants; Lipids; Nanoparticles; Particle Size; Thioctic Acid; Ubiquinone

Topics: Antioxidants; Child; Humans; Male; Optic Atrophy, Hereditary, Leber; Ubiquinone; Vision, Low

Idebenone, the synthetic analog of coenzyme Q10 can improve electron transport in mitochondria. Therefore, it is used in the treatment of Alzheimer's disease and other cognitive impairments. However, the mechanism of its action on neurodevelopment is still to be elucidated. Here we demonstrate that the cellular response of human induced pluripotent stem cells (hiPSC) to idebenone depends on the stage of neural differentiation. When: neural stem cells (NSC), early neural progenitors (eNP) and advanced neural progenitors (NP) have been studied a significant stimulation of mitochondrial biogenesis was observed only at the eNP stage of development. This coexists with the enhancement of cell viability and increase in total cell number. In addition, we report novel idebenone properties in a possible regulation of neural stem cells fate decision: only eNP stage responded with up-regulation of both neuronal (MAP2), astrocytic (GFAP) markers, while at NSC and NP stages significant down-regulation of MAP2 expression was observed, promoting astrocyte differentiation. Thus, idebenone targets specific stages of hiPSC differentiation and may influence the neural stem cell fate decision.

Topics: Biomarkers; Cell Line; Cell Lineage; Cell Proliferation; Cell Survival; DNA, Mitochondrial; Dose-Response Relationship, Drug; Gene Expression Regulation; Humans; Induced Pluripotent Stem Cells; Membrane Potential, Mitochondrial; Mitochondria; Neural Stem Cells; Neurogenesis; Neurons; Organelle Biogenesis; Phenotype; Reactive Oxygen Species; Ubiquinone

Maternal diabetes programs metabolic and cardiovascular diseases in the offspring. Here, we demonstrated increased pro-oxidant/pro-inflammatory markers in the heart of 2-day-old offspring of diabetic rats, previous to the induction of metabolic alterations. At a pre-pubertal stage, sex-dependent changes were evidenced in the diabetic group, as only males showed increased glycemia as well as increased concentrations of nitrated proteins, matrix metalloproteinase-9 and peroxisome proliferator activated receptor α (PPARα) in the heart. Differently, the heart of male and female offspring of diabetic rats showed increased levels of connective tissue growth factor (CTGF). Maternal treatments with idebenone, a mitochondrial antioxidant, led to reductions in all the pro-oxidant and pro-inflammatory markers evaluated and in PPARα protein expression in the heart of the offspring of diabetic rats. The results of the present study highlight the gender dependence and the role of oxidative stress in the diabetes-induced intrauterine programming of heart alterations.

Topics: Animals; Antioxidants; Connective Tissue Growth Factor; Diabetes Mellitus, Experimental; Female; Male; Maternal-Fetal Exchange; Matrix Metalloproteinase 9; Mitochondria; Myocardium; Nitric Oxide; Oxidative Stress; PPAR alpha; Pregnancy; Rats, Wistar; Ubiquinone

Leber hereditary optic neuropathy (LHON) is currently estimated as the most frequent mitochondrial disease (1 in 27,000-45,000). Its molecular pathogenesis and natural history is now fairly well understood. LHON also is the first mitochondrial disease for which a treatment has been approved (idebenone-Raxone, Santhera Pharmaceuticals) by the European Medicine Agency, under exceptional circumstances because of the rarity and severity of the disease. However, what remains unclear includes the optimal target population, timing, dose, and frequency of administration of idebenone in LHON due to lack of accepted definitions, criteria, and general guidelines for the clinical management of LHON. To address these issues, a consensus conference with a panel of experts from Europe and North America was held in Milan, Italy, in 2016. The intent was to provide expert consensus statements for the clinical and therapeutic management of LHON based on the currently available evidence. We report the conclusions of this conference, providing the guidelines for clinical and therapeutic management of LHON.

Topics: Antioxidants; Congresses as Topic; Consensus; Disease Management; Humans; International Cooperation; Ophthalmology; Optic Atrophy, Hereditary, Leber; Societies, Medical; Ubiquinone

Patients with Leber hereditary optic neuropathy (LHON) have a progressive decrease of their visual acuity which can deteriorate to <0.1. Some patients can have a partial recovery of their vision in one or both eyes. One prognostic factor associated with a recovery of vision is an early-age onset. The purpose of this study was to determine other clinical factors that are predictive of a good visual recovery.. Sixty-one Japanese LHON patients, with the 11,778 mutation and a mean age of 23.1 ± 12.1 years at the onset, were studied. All patients were initially examined at an acute stage of LHON and were followed for 3 to 10 years. At 1 year after the onset, the lowest visual acuity was <0.1 in all eyes. We studied the following parameters of patients with/without a final visual acuity of ≥ 0.2: sex; heavy consumption of cigarettes and alcohol; taking idebenone; mean age at onset; mean lowest visual acuity; and distribution of the lowest and the final visual acuity.. Fifteen (24.6%) of the 61 patients or 25 (20.5%) of the 122 eyes had a recovery of their visual acuity to ≥ 0.2. The mean age at onset of these 15 patients with visual recovery to ≥ 0.2 was 17.5 ± 7.7 years, and that of the 46 patients without visual recovery to ≥ 0.2 was 25.0 ± 12.8 years (P = 0.02, Mann-Whitney U test). The mean lowest visual acuity of the 25 eyes with visual recovery ≥ 0.2 was 0.04, and that of the 97 eyes without visual recovery to ≥ 0.2 was 0.015 (P < 0.001, Mann-Whitney U test). Fifty percent (15/30) of the eyes whose lowest visual acuity was ≥ 0.04 during 1 year after the onset had a visual recovery to ≥ 0.2, while 11% (10/92) of the eyes whose the lowest visual acuity was ≤ 0.03 had a visual recovery to ≥ 0.2 (P < 0.001, χ. A final visual acuity of ≥ 0.2 was associated with a less severe reduction of the visual acuity at 1 year after the onset. Our findings can be used to predict the visual prognosis in LHON patients.

Topics: Adolescent; Adult; Age of Onset; Aged; Antioxidants; Ascorbic Acid; Child; DNA Mutational Analysis; DNA, Mitochondrial; Female; Follow-Up Studies; Humans; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Point Mutation; Polymerase Chain Reaction; Prognosis; Recovery of Function; Retrospective Studies; Riboflavin; Ubiquinone; Vision Disorders; Visual Acuity; Visual Field Tests; Vitamin B Complex; Young Adult

Topics: Antioxidants; Humans; Optic Atrophy, Hereditary, Leber; Treatment Outcome; Ubiquinone

Topics: Adolescent; Adult; Aspartic Acid; Cerebellum; Child; Choline; Diffusion Magnetic Resonance Imaging; Female; Friedreich Ataxia; Humans; Linear Models; Male; Middle Aged; Neuroprotective Agents; Proton Magnetic Resonance Spectroscopy; Severity of Illness Index; Ubiquinone; Young Adult

Adapted forms for administration to infants are limited. The proposed study was performed to propose oral liquid formulations of idebenone in Ora-Plus and either Ora-Sweet or Ora-Sweet SF, Ora-Blend, Ora-Blend SF and Inorpha. Each formulation was stored in 30 ml amber glass bottle at 5 or 25 °C for 90 days. Idebenone contents in these suspensions, determined by a stability-indicating high-performance liquid chromatography method, remained stable at least 90 days in Inorpha when stored at the two temperatures. In Ora-Blend, the stability was estimated at 14 days and in other suspensions at 20 days at the two temperatures. After 90 days storage, the pH of Ora-Plus and Ora-Sweet or Ora-Sweet SF changed between -0.10 and -0.25 units. For others suspensions, the pH changes were not significant (< -0.09 unit). No change was observed in color, odor or visual microbiology. To conclude, we recommended the use of idebenone in Inorpha vehicle stable for at least 90 days at 25 °C.

Topics: Administration, Oral; Antioxidants; Child; Drug Compounding; Drug Stability; Drug Storage; Humans; Pharmaceutical Vehicles; Suspensions; Ubiquinone

A novel, simple and reliable method based on micellar electrokinetic chromatography with ultraviolet detection was developed to analyze idebenone in a pediatric formulation. Idebenone is a synthetic short chain benzoquinone that acts as an electron carrier in the mitochondrial electron transport chain facilitating the production of adenosine triphosphate. It can be found in two different redox states that differ in their physiological properties. Idebenone has been investigated as a treatment in several neurological disorders like Friedreich's ataxia, Leber's hereditary optic neuropathy, mitochondrial encephalomyopathies and senile dementia. Accordingly, a micellar electrokinetic chromatography was employed to discriminate both redox forms. The final optimized system was validated in terms of selectivity, linearity (r2 0.992), limit of detection (0.5 µg/mL), limit of quantification (1.8 µg/mL), intra- and inter-day precision (RSD ≤ 2) and accuracy in terms of recovery studies (99.3-100.5%). Robustness was studied following a Plackett-Burman design. Finally, the validated system was applied to the analysis of idebenone in a pediatric formulation.

Topics: Chromatography, Micellar Electrokinetic Capillary; Limit of Detection; Linear Models; Reproducibility of Results; Suspensions; Ubiquinone

To investigate mitophagy in 5 patients with severe dominantly inherited optic atrophy (DOA), caused by depletion of OPA1 (a protein that is essential for mitochondrial fusion), compared with healthy controls.. Patients with severe DOA (DOA plus) had peripheral neuropathy, cognitive regression, and epilepsy in addition to loss of vision. We quantified mitophagy in dermal fibroblasts, using 2 high throughput imaging systems, by visualizing colocalization of mitochondrial fragments with engulfing autophagosomes.. Fibroblasts from 3 biallelic OPA1(-/-) patients with severe DOA had increased mitochondrial fragmentation and mitochondrial DNA (mtDNA)-depleted cells due to decreased levels of OPA1 protein. Similarly, in siRNA-treated control fibroblasts, profound OPA1 knockdown caused mitochondrial fragmentation, loss of mtDNA, impaired mitochondrial function, and mitochondrial mislocalization. Compared to controls, basal mitophagy (abundance of autophagosomes colocalizing with mitochondria) was increased in (1) biallelic patients, (2) monoallelic patients with DOA plus, and (3) OPA1 siRNA-treated control cultures. Mitophagic flux was also increased. Genetic knockdown of the mitophagy protein ATG7 confirmed this by eliminating differences between patient and control fibroblasts.. We demonstrated increased mitophagy and excessive mitochondrial fragmentation in primary human cultures associated with DOA plus due to biallelic OPA1 mutations. We previously found that increased mitophagy (mitochondrial recycling) was associated with visual loss in another mitochondrial optic neuropathy, Leber hereditary optic neuropathy (LHON). Combined with our LHON findings, this implicates excessive mitochondrial fragmentation, dysregulated mitophagy, and impaired response to energetic stress in the pathogenesis of mitochondrial optic neuropathies, potentially linked with mitochondrial mislocalization and mtDNA depletion.

Topics: Antioxidants; Cells, Cultured; Cognition Disorders; DNA Mutational Analysis; DNA, Mitochondrial; Family Health; Female; Fibroblasts; GTP Phosphohydrolases; Humans; Male; Membrane Potential, Mitochondrial; Mitochondrial Proteins; Mitophagy; Mutation; Optic Atrophy; Pedigree; Protein Kinases; RNA, Small Interfering; Transfection; Ubiquinone; Ubiquitin-Protein Ligases

Leber hereditary optic neuropathy (LHON) is an important cause of mitochondrial blindness among young adults. In this study, we investigated the potential of four quinone analogues (CoQ

Topics: Adenosine Triphosphate; Adolescent; Antioxidants; Cells, Cultured; Energy Metabolism; Fibroblasts; Humans; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Quinones; Reactive Oxygen Species; Ubiquinone; Young Adult

Idebenone is a high permeable drug with very slight water solubility that affects the dissolution rate in the biological fluids, causing an irregular and limited in vivo absorption after oral administration. Moreover, it is marketed in Europe as tablets equivalent to 150 mg, with the consequent administration of multiple dose of solid unit to obtain the correct dose, a deterrent for the patients' compliance. According to these considerations, our goal was to develop spray-dried microparticles using a soluble β-cyclodextrin (CD) polymer and an enhancer of dissolution rate, such as carboxymethyl cellulose, to obtain a formulation easily dosable and soluble in water. The complex in solution was evaluated by phase solubility studies and the Idebenone/CD molar ratio selected was 1:1. According to Higuchi and Connors, adding carboxymethyl cellulose, a Bs-type profile was obtained. This result was due to the presence of carboxymethyl cellulose that competes with the CD in forming Idebenone microsystems, reducing of 10-fold the formulation bulk. UV-Vis absorption, (1)H nuclear magnetic resonance and circular dichroism showed the formation of the CD/Idebenone inclusion complex confirmed also by differential scanning calorimetry, Fourier transform infrared spectroscopy and fluorescence microscope (FM). The water solubility data and the in vitro dissolution tests performed in simulated gastric fluid, showed an increase of the drug water interaction due to the presence of the CD and carboxymethyl cellulose, both able to improve drug wettability, water solubility and dissolution rate. This approach seems to be suitable to produce microsystems which are able to enhance the in vivo absorption of Idebenone after oral administration and to increase the patient compliance.

Topics: Administration, Oral; Antioxidants; beta-Cyclodextrins; Cellulase; Chromatography, High Pressure Liquid; Drug Compounding; Drug Stability; Humans; Patient Compliance; Technology, Pharmaceutical; Ubiquinone

Friedreich's ataxia (FRDA), a recessive neurodegenerative disorder commonly associated with hypertrophic cardiomyopathy, is caused by silencing of the frataxin (FXN) gene encoding the mitochondrial protein involved in iron-sulfur cluster biosynthesis.. Application of our previously established FRDA human induced pluripotent stem cell (hiPSC) derived cardiomyocytes model as a platform to assess the efficacy of treatment with either the antioxidant coenzyme Q10 analog, idebenone (IDE) or the iron chelator, deferiprone (DFP), which are both under clinical trial.. DFP was able to more significantly suppress synthesis of reactive oxygen species (ROS) than IDE at the dosages of 25 μM and 10nM respectively which agreed with the reduced rate of intracellular accumulation of iron by DFP treatment from 25 to 50 μM. With regard to cardiac electrical-contraction (EC) coupling function, decay velocity of calcium handling kinetics in FRDA-hiPSC-cardiomyocytes was significantly improved by DFP treatment but not by IDE. Further mechanistic studies revealed that DFP also modulated iron induced mitochondrial stress as reflected by mitochondria network disorganization and decline level of respiratory chain protein, succinate dehydrogenase (CxII) and cytochrome c oxidase (COXIV). In addition, iron-response protein (IRP-1) regulatory loop was overridden by DFP as reflected by resumed level of ferritin (FTH) back to basal level and the attenuated transferrin receptor (TSFR) mRNA level suppression thereby reducing further iron uptake.. DFP modulated iron homeostasis in FRDA-hiPSC-cardiomyocytes and effectively relieved stress-stimulation related to cardiomyopathy. The resuming of redox condition led to the significantly improved cardiac prime events, cardiac electrical-coupling during contraction.

Topics: Antioxidants; Deferiprone; Drug Evaluation, Preclinical; Frataxin; Friedreich Ataxia; Gene Expression Regulation; Homeostasis; Humans; Induced Pluripotent Stem Cells; Iron; Iron Chelating Agents; Iron-Binding Proteins; Myocytes, Cardiac; Oxidative Stress; Pyridones; Reverse Transcriptase Polymerase Chain Reaction; RNA; Ubiquinone

Dominant optic atrophy (DOA) arises from mutations in the OPA1 gene that promotes fusion of the inner mitochondrial membrane and plays a role in maintaining ATP levels. Patients display optic disc pallor, retinal ganglion cell (RGC) loss and bilaterally reduced vision. We report a randomized, placebo-controlled trial of idebenone at 2000 mg/kg/day in 56 Opa1 mutant mice (B6;C3-Opa1(Q285STOP)), with RGC dendropathy and visual loss, and 63 wildtype mice. We assessed cellular responses in the retina, brain and liver and RGC morphology, by diolistic labeling, Sholl analysis and quantification of dendritic morphometric features. Vision was assessed by optokinetic responses. ATP levels were raised by 0.57 nmol/mg (97.73%, p=0.035) in brain from idebenone-treated Opa1 mutant mice, but in the liver there was an 80.35% (p=0.011) increase in oxidative damage. NQO1 expression in Opa1 mutant mice was reduced in the brain (to 30.5%, p=0.002) but not in retina, and neither expression level was induced by idebenone. ON-center RGCs failed to show major recovery, other than improvements in secondary dendritic length (by 53.89%, p=0.052) and dendritic territory (by 2.22 × 10(4) μm(2) or 90.24%, p=0.074). An improvement in optokinetic response was observed (by 12.2 ± 3.2s, p=0.003), but this effect was not sustained over time. OFF-center RGCs from idebenone-treated wildtype mice showed shrinkage in total dendritic length by 2.40 mm (48.05%, p=0.025) and a 47.37% diminished Sholl profile (p=0.029). Visual function in wildtype idebenone-treated mice was impaired (2.9 fewer head turns than placebo, p=0.007). Idebenone appears largely ineffective in protecting Opa1 heterozygous RGCs from dendropathy. The detrimental effect of idebenone in wildtype mice has not been previously observed and raises some concerns.

Topics: Animals; Antioxidants; Blotting, Western; Dendrites; Disease Models, Animal; Female; GTP Phosphohydrolases; Immunohistochemistry; Male; Mice; Mice, Mutant Strains; Optic Atrophy, Autosomal Dominant; Random Allocation; Retinal Ganglion Cells; Ubiquinone; Visual Acuity

Idebenone is a synthetic analog of coenzyme Q; both share a quinone moiety but idebenone has a shorter lipophilic tail ending with a hydroxyl group. Differential scanning calorimetry experiments showed that both idebenone and idebenol widened and shifted the phase transition of 1,2-dipalmitoylphosphatidylcholine (DPPC) to a lower temperature and a phase separation with different concentrations of these molecules was observed. Also small angle X-ray diffraction and wide angle X-ray diffraction revealed that both, idebenone and idebenol, induced laterally separated phases in fluid membranes when included in DPPC membranes. Electronic profiles showed that both forms, idebenone and idebenol, reduced the thickness of the fluid membrane. (2)H NMR measurements showed that the order of the membrane decreased at all temperatures in the presence of idebenone or idebenol, the greatest disorder being observed in the segments of the acyl chains close to the lipid-water interface. (1)H NOESY MAS NMR spectra were obtained using 1-palmitoyl-2-oleoyl-phosphatidylcholine membranes and results pointed to a similar location in the membrane for both forms, with the benzoquinone or benzoquinol rings and their terminal hydroxyl group of the hydrophobic chain located near the lipid/water interface of the phospholipid bilayer and the terminal hydroxyl group of the hydrophobic chain of both compounds located at the lipid/water interface. Taken together, all these different locations might explain the different physiological behavior shown by the idebenone/idebenol compared with the ubiquinone-10/ubiquinol-10 pair in which both compounds are differently localized in the membrane.

Topics: 1,2-Dipalmitoylphosphatidylcholine; Calorimetry, Differential Scanning; Membrane Fluidity; Membranes, Artificial; Quinones; Solubility; Ubiquinone; Water; X-Ray Diffraction

Idebenone (Raxone(®)), a short-chain benzoquinone, is the only disease-specific drug approved to treat visual impairment in adolescents and adults with Leber's hereditary optic neuropathy (LHON), a rare genetic mitochondrial disease that causes rapid and progressive bilateral vision loss. The mechanism of action of idebenone involves its antioxidant properties and ability to act as a mitochondrial electron carrier. Idebenone overcomes mitochondrial complex I respiratory chain deficiency in patients with LHON by transferring electrons directly to mitochondrial complex III (by-passing complex I), thereby restoring cellular energy (ATP) production and re-activating inactive-but-viable retinal ganglion cells, which ultimately prevents further vision loss and promotes vision recovery. The approval of idebenone in the treatment of LHON was based on the overall data from a randomized clinical trial, a follow-up study and real-world data. Taken together, these studies provide convincing evidence that oral idebenone 900 mg/day for 24 weeks has persistent beneficial effects in preventing further vision impairment and promoting vision recovery in patients with LHON relative to the natural course of the disease. Therefore, idebenone is a valuable agent to treat visual impairment in adolescents and adults with LHON.

Topics: Antioxidants; Humans; Optic Atrophy, Hereditary, Leber; Randomized Controlled Trials as Topic; Ubiquinone

Topics: Acidosis, Lactic; Adolescent; Adult; Aged; Aged, 80 and over; Antioxidants; Cells, Cultured; Child; Child, Preschool; DNA, Mitochondrial; Female; Fibroblasts; Humans; Infant; Infant, Newborn; Leigh Disease; Male; Microtubule-Associated Proteins; Middle Aged; Mitochondrial Dynamics; Mitochondrial Membrane Transport Proteins; Mitochondrial Precursor Protein Import Complex Proteins; Mitophagy; Mutation; Neurology; Ubiquinone; Young Adult

There is an urgent need to identify new treatments for tuberculosis (TB), a major infectious disease caused by Mycobacterium tuberculosis (Mtb), which results in 1.5 million deaths each year. We have targeted two essential enzymes in this organism that are promising for antibacterial therapy and reported to be inhibited by naphthoquinones. ThyX is an essential thymidylate synthase that is mechanistically and structurally unrelated to the human enzyme. DNA gyrase is a DNA topoisomerase present in bacteria and plants but not animals. The current study set out to understand the structure-activity relationships of these targets in Mtb using a combination of cheminformatics and in vitro screening. Here, we report the identification of new Mtb ThyX inhibitors, 2-chloro-3-(4-methanesulfonylpiperazin-1-yl)-1,4-dihydronaphthalene-1,4-dione) and idebenone, which show modest whole-cell activity and appear to act, at least in part, by targeting ThyX in Mtb.

Topics: Bacterial Proteins; Bayes Theorem; DNA Gyrase; Enzyme Inhibitors; Machine Learning; Models, Molecular; Mycobacterium tuberculosis; Naphthoquinones; Thymidylate Synthase; Ubiquinone; User-Computer Interface

Considerable evidence demonstrated that the central role of reactive oxygen species and reactive nitrogen species (ROS and RNS) in the development of thermal hyperalgesia is associated to acute and chronic inflammation. Idebenone (IDE), a synthetic analogue of the endogenous cellular antioxidant coenzyme Q10 (CoQ10), is an active drug in the central nervous system which shows a protection in a variety of neurological disorders. Since it is lipophilic, poorly water soluble and highly bound to plasma proteins, different technological approaches have been explored to increase its solubility and new pharmaceutical properties. Therefore, it has been complexed with HP-β-cyclodextrins (HP) and its efficacy has been assessed in an animal model of carrageenan-induced thermal hyperalgesia. All male rats used for this study received a subplantar injection of carrageenan into the right hindpaw in the presence or absence of IDE alone and IDE/HP complex. We observed that IDE poorly reduced painful carrageenan effects whereas IDE/HP complex was able to prevent carrageenan-induced hyperalgesia and edema in a dose-dependent manner, reducing spinal MDA levels and protein nitration. Hence, our results demonstrated that when complexed with HP, idebenone exerts a potent analgesic and anti-inflammatory efficacy.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Analgesics; Animals; Anti-Inflammatory Agents; Antioxidants; Carrageenan; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Compounding; Edema; Hyperalgesia; Inflammation; Male; Malondialdehyde; Oxidative Stress; Rats, Sprague-Dawley; Spinal Cord; Superoxide Dismutase; Time Factors; Ubiquinone

Topics: Animals; Apoptosis; Chlorocebus aethiops; COS Cells; Cytoskeletal Proteins; Eye Proteins; Glaucoma, Open-Angle; Glycoproteins; Humans; Mutation; Ubiquinone

Topics: Animals; Antibodies, Monoclonal, Humanized; Antigens, CD20; Azetidines; B-Lymphocytes; Benzamides; Benzyl Compounds; Blood-Brain Barrier; Clinical Trials as Topic; Disease Progression; Dogs; Drug Approval; Fingolimod Hydrochloride; Hope; Humans; Male; Mice; Multiple Sclerosis, Chronic Progressive; Neuroprotective Agents; Piperidines; Precision Medicine; Pyridines; Rituximab; Thiazoles; Ubiquinone; United States; United States Food and Drug Administration

Idebenone (IDE) is a lipophilic benzoquinone electron carrier synthetic analogue of coenzyme Q10, which behaves as an antioxidant and free radical scavenging molecule. Recently, the therapeutic application of IDE in Leber's hereditary optic neuropathy has been discussed. This work was aimed at evaluating the encapsulation of IDE in solid-lipid nanoparticles (SLN). In particular, we tested the possibility of adapting the quasi-emulsion solvent diffusion technique, already proposed to produce polymeric nanoparticles, to prepare positively charged SLN with different compositions. Such a charge, due to the addition of a cationic lipid, would facilitate the interaction with the negatively charged eye surface epithelium, with a consequent longer pre-corneal residence time of the colloidal systems. In a preliminary evaluation of the produced IDE-loaded SLN, the antioxidant activity of the drug was demonstrated using an oxygen radical absorbance capacity assay. Encapsulation of the drug in the nanocarrier systems seems able to protect IDE from degradation and prolong its antioxidant potential.

Topics: Antioxidants; Cations; Drug Carriers; Lipids; Nanoparticles; Reactive Oxygen Species; Ubiquinone

Mitoquinone (MitoQ) attenuates aminoglycoside (AG)-induced upregulation of the proapoptotic molecules Bak and harakiri (Hrk) and decreases the percentage of apoptotic House Ear Institute Organ of Corti 1 (HEI-OC1) cells.. The primary mechanism of AG ototoxicity is the formation of reactive oxygen species, which leads to hair cell death via apoptotic and nonapoptotic pathways. Antioxidants have been shown to protect against AG ototoxicity. Mitoquinone is a mitochondria-targeted derivative of the antioxidant ubiquinone. Thus, MitoQ may be more effective in preventing AG ototoxicity compared with untargeted antioxidants.. Ribonucleic acid from untreated HEI-OC1 cells and cells exposed to gentamicin with and without preincubation with MitoQ, idebenone (IDB, an untargeted ubiquinone), or decylTPP (positive control) were used to assess gene expression of Bak and Hrk using real-time polymerase chain reaction. Protein expression of Bak and Hrk was determined by Western blotting. Annexin V assay using flow cytometry was performed to assess the percentage of apoptotic HEI-OC1 cells treated with gentamicin with and without preincubation with MitoQ, decylTPP, or IDB.. Preincubation of HEI-OC1 cells with MitoQ significantly decreased the gentamicin-induced upregulation of Bak gene (p = 0.03) but not preincubation with IDB (p = 0.87). Harakiri levels were very low that relative quantification could not be carried out. Protein levels of Bak and Hrk were not different between treatments. Annexin V assay showed that gentamicin increased the percentage of apoptotic cells (p < 0.05) compared with control. However, the percentages of apoptotic cells in gentamicin-treated and cells pretreated with the antioxidants MitoQ or IDB were not different.. Mitoquinone attenuated the gentamicin-induced upregulation of the Bak gene but not its product, the proapoptotic molecule Bak, and MitoQ did not significantly decrease the gentamicin-induced cell apoptosis in vitro. Further in vivo studies are needed to assess the clinical significance of these findings.

Topics: Antioxidants; Apoptosis; Apoptosis Regulatory Proteins; bcl-2-Associated X Protein; Cell Line; Gentamicins; Hair Cells, Auditory; Humans; Mitochondria; Organophosphorus Compounds; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Ubiquinone

The mechanisms of general anesthesia by volatile drugs remain largely unknown. Mitochondrial dysfunction and reduction in energy levels have been suggested to be associated with general anesthesia status. 2-Deoxy-D-glucose (2-DG), an analog of glucose, inhibits hexokinase and reduces cellular levels of adenosine triphosphate (ATP). 3-Nitropropionic acid is another compound which can deplete ATP levels. In contrast, idebenone and L-carnitine could rescue deficits of energy. We therefore sought to determine whether 2-DG and/or 3-nitropropionic acid can enhance the anesthetic effects of isoflurane, and whether idebenone and L-carnitine can reverse the actions of 2-DG.. C57BL/6J mice (8 months old) received different concentrations of isoflurane with and without the treatments of 2-DG, 3-nitropropionic acid, idebenone, and L-carnitine. Isoflurane-induced loss of righting reflex (LORR) was determined in the mice. ATP levels in H4 human neuroglioma cells were assessed after these treatments. Finally, 31P-magnetic resonance spectroscopy was used to determine the effects of isoflurane on brain ATP levels in the mice.. 2-DG enhanced isoflurane-induced LORR (P = 0.002, N = 15). 3-Nitropropionic acid also enhanced the anesthetic effects of isoflurane (P = 0.005, N = 15). Idebenone (idebenone + saline versus idebenone + 2-DG: P = 0.165, N = 15), but not L-carnitine (L-carnitine + saline versus L-carnitine + 2-DG: P < 0.0001, N = 15), inhibited the effects of 2-DG on enhancing isoflurane-induced LORR in the mice, as evidenced by 2-DG not enhancing isoflurane-induced LORR in the mice pretreated with idebenone. Idebenone (idebenone + saline versus idebenone + 2-DG: P = 0.177, N = 6), but not L-carnitine (L-carnitine + saline versus L-carnitine + 2-DG: P = 0.029, N = 6), also mitigated the effects of 2-DG on reducing ATP levels in cells, as evidenced by 2-DG not decreasing ATP levels in the cells pretreated with idebenone. Finally, isoflurane decreased ATP levels in both cultured cells and mouse brains (β-ATP: P = 0.003, N = 10; β-ATP/phosphocreatine: P = 0.006, N = 10; β-ATP/inorganic phosphate: P = 0.001, N = 10).. These results from our pilot studies have established a system and generated a hypothesis that 2-DG enhances anesthetic effects via reducing energy levels. These findings should promote further studies to investigate anesthesia mechanisms.

Topics: Adenosine Triphosphate; Anesthetics, Inhalation; Animals; Antimetabolites; Antioxidants; Carnitine; Deoxyglucose; Drug Synergism; Energy Metabolism; Humans; Isoflurane; Mice; Mice, Inbred C57BL; Nitro Compounds; Propionates; Ubiquinone; Vitamins

This study investigates the effect of insulin combined with idebenone on blood-brain barrier (BBB) permeability in experimental streptozotocin-induced diabetic rats as well as the underlying mechanisms. With a diabetic rat model, we show that insulin and idebenone normalize body weight and water intake and restore BBB permeability and that their combination displays a synergistic effect. The results from transmission electron microscopy show that the combination of insulin and idebenone significantly closed the tight junction (TJ) in diabetic rats. The results from Western blotting in diabetic rats show that the upregulation of TJ-associated proteins occludin, and zonula occludens (ZO)-1 caused by the combination of insulin and idebenone is more remarkable than that with either agent alone. In addition, the activations of reactive oxygen species (ROS) and advanced glycation end products (AGEs) and the expression levels of receptors for advanced glycation end-products (RAGE) and nuclear factor-κB (NF-κB) were significantly decreased after treatment with insulin and idebenone in diabetic rats. These results suggest that the combination of insulin and idebenone could decrease the BBB permeability in diabetic rats by upregulating the expression of occludin, claudin-5, and ZO-1 and that the ROS/AGE/RAGE/NF-κB signal pathway might be involved in the process.

Topics: Animals; Antioxidants; Blood-Brain Barrier; Capillary Permeability; Diabetes Mellitus, Experimental; Disease Models, Animal; Hypoglycemic Agents; Insulin; Male; Microscopy, Electron, Transmission; Nucleoproteins; Rats; Rats, Wistar; Reactive Oxygen Species; Statistics, Nonparametric; Ubiquinone

In past years, nanostructured lipid carriers (NLCs) have emerged as novel topical antioxidant delivery systems because of combined positive features of liposomes and polymeric nanoparticles. Here, we seek to unlock the possibility of idebenone (IDB; an antioxidant)-loaded NLCs (IDB-NLCs) cellular interactions such as, viability and uptake, and its photoprotective effects against Ultraviolet-B (UVB)-mediated oxidative stress in immortal human keratinocyte cell line (HaCaT). The two-step preformulation strategy followed by three-level, three-variable, L9 (3(3)) Taguchi robust orthogonal design employed was important in improving IDB-NLCs key physicochemical aspects such as, entrapment efficiency, drug release (sustained), occlusion, skin deposition and physical stability. UV crosslinker, confocal microscopy and flow cytometry techniques were used to (1) mediate oxidative stress in HaCaT cells, (2) study a qualitative cellular uptake, (3) measure intracellular reactive oxygen species (ROS), and mitochondrial membrane potential, respectively. NLCs markedly improved biocompatibility of IDB under normal as well as stress conditions. Quantitative and qualitative cell uptake studies demonstrated a significant uptake of IDB-NLCs (3-fold increase) and nile red-labeled IDB-NLCs (NR-IDB-NLCs) at 2 h, respectively, hence exerted improved photoprotective effects.

Topics: Biological Transport; Caprylates; Cell Line; Cell Survival; Drug Carriers; Drug Liberation; Glycerides; Humans; Keratinocytes; Membrane Potential, Mitochondrial; Microscopy, Electron, Transmission; Nanoparticles; Radiation-Protective Agents; Reactive Oxygen Species; Surface-Active Agents; Triglycerides; Ubiquinone; Ultraviolet Rays

Genetic defects in the UBE3A gene, which encodes for the imprinted E6-AP ubiquitin E3 ligase (UBE3A), is responsible for the occurrence of Angelman syndrome (AS), a neurodegenerative disorder which arises in 1 out of every 12,000-20,000 births. Classical symptoms of AS include delayed development, impaired speech, and epileptic seizures with characteristic electroencephalography (EEG) readings. We have previously reported impaired mitochondrial structure and reduced complex III in the hippocampus and cerebellum in the Ube3a(m-/p+) mice. CoQ10 supplementation restores the electron flow to the mitochondrial respiratory chain (MRC) to ultimately increase mitochondrial antioxidant capacity. A number of recent studies with CoQ10 analogues seem promising in providing therapeutic benefit to patients with a variety of disorders. CoQ10 therapy has been reported to be safe and relatively well-tolerated at doses as high as 3000mg/day in patients with disorders of CoQ10 biosynthesis and MRC disorders. Herein, we report administration of idebenone, a potent CoQ10 analogue, to the Ube3a(m-/p+) mouse model corrects motor coordination and anxiety levels, and also improves the expression of complexes III and IV in hippocampus CA1 and CA2 neurons and cerebellum in these Ube3a(m-/p+) mice. However, treatment with idebenone illustrated no beneficial effects in the reduction of oxidative stress. To our knowledge, this is the first study to suggest an improvement in mitochondrial respiratory chain dysfunction via bioenergetics modulation with a CoQ10 analogue. These findings may further elucidate possible cellular and molecular mechanism(s) and ultimately a clinical therapeutic approach/benefit for patients with Angelman syndrome.

Topics: Angelman Syndrome; Animals; Antioxidants; Cerebellum; Disease Models, Animal; Electron Transport; Hippocampus; Mice; Mitochondria; Motor Activity; Oxidative Stress; Ubiquinone; Ubiquitin-Protein Ligases

The present study investigated the in vitro and in vivo effects of individual and combined doses of idebenone, carnosine and vitamin E on ameliorating some of the biochemical indices of nano-sized titanium dioxide (n-TiO2) in mice liver.. The in vitro cytotoxic effect of nano-sized anatase TiO2 (21 nm) on hepatic cell lines (HepG 2) was investigated. Additionally, n-TiO2 was orally administered (150 mg/kg/day) for 2 weeks, followed by a daily intragastric gavage of the aforementioned antioxidants for 1 month.. n-TiO2 induced significant cytotoxicity in hepatic cell lines and elevated the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepatic total antioxidant capacity (TAC) and nitrite/nitrate (NOx) levels. Meanwhile, glutathione-S-transferase (GST) activity was significantly reduced. Moreover, RT-PCR and western blot analysis showed that n-TiO2 significantly altered the mRNA and protein expressions of transforming growth factor-beta (TGF-β1) and Smad-2, as well as vascular endothelium growth factor (VEGF). Histopathological examination of hepatic tissue reinforced these results.. Idebenone, carnosine and vitamin E ameliorated the deviated parameters with the combination regimen demonstrating the most pronounced effect. Oxidative stress, liver fibrosis and angiogenesis may be implicated in n-TiO2-induced liver toxicity.

Topics: Alanine Transaminase; Angiogenesis Inhibitors; Animals; Antioxidants; Aspartate Aminotransferases; Carnosine; Cell Line, Tumor; Chemical and Drug Induced Liver Injury; Glutathione Transferase; Hep G2 Cells; Humans; Liver Cirrhosis; Male; Mice; Nitrates; Nitrites; Smad2 Protein; Titanium; Transforming Growth Factor beta; Ubiquinone; Vascular Endothelial Growth Factor A; Vitamin E

Topics: Antioxidants; Humans; Male; Muscular Dystrophy, Duchenne; Respiration Disorders; Ubiquinone

It is generally accepted that Friedreich's ataxia (FRDA) is caused by a deficiency in frataxin expression, a mitochondrial protein involved in iron homeostasis, which mainly affects the brain, dorsal root ganglia of the spinal cord, heart and in certain cases the pancreas. However, there is little knowledge as to other possible genes that may be affected in this disorder, and which can contribute to its complexity. In the current study we compared human periodontal ligament cells gene expression of healthy individuals and FRDA patients. The expression of active-caspase 3, as well as other apoptosis-related genes, was increased in the FRDA cells. Furthermore, iron-sulphur cluster genes, as well as oxidative stress-related genes were overexpressed in FRDA. Moreover, brain-derived neurotrophic factor, neuregulin 1 and miR-132 were all upregulated. These three genes are capable of regulating the expression of each other. Interestingly, when the cells from FRDA patients were co-cultured in the presence of idebenone and deferiprone, caspase expression decreased while antioxidant gene expression, as well as frataxin expression, increased. Regarding epigenetic mechanisms, the frataxin gene was hypermethylated, compared to the healthy counterparts, in the upstream GAA repetitive region. Of the three DNA methyltransferases, DNMT1 but not DNMT3׳s gene expression was higher in FRDA cells. In conclusion, our data show that FRDA cells present altered expression of genes related to cell cycle, oxidative stress and iron homeostasis which may be implicated in the increased apoptotic levels. Also, the altered expression is in a certain degree normalized in the presence of idebenone and deferiprone.

Topics: Antioxidants; Apoptosis; Azacitidine; Brain-Derived Neurotrophic Factor; Caspase 3; Cells, Cultured; Decitabine; Deferiprone; DNA (Cytosine-5-)-Methyltransferase 1; DNA (Cytosine-5-)-Methyltransferases; DNA Methylation; Epigenesis, Genetic; Frataxin; Friedreich Ataxia; Gene Expression Profiling; Humans; Iron Chelating Agents; Iron-Binding Proteins; MicroRNAs; Neuregulin-1; Oxidative Stress; Periodontal Ligament; Pyridones; Superoxide Dismutase; Ubiquinone

The present study compares three vesicular systems, cationic LeciPlex, invasomes, and conventional liposomes for their ability to deliver drugs deep into the skin. Skin penetration ability of the three vesicular systems was studied for two drugs namely idebenone (antioxidant/anticancer) and azelaic acid (antiacne). All systems showed sizes in nanometer range with small polydispersity indices. Vesicular systems were characterized by CryoTEM studies to understand the differences in morphology of the vesicular systems. Ex vivo human skin penetration studies suggested a pattern in penetration of drugs in different layers of the skin: LeciPlex showed higher penetration for idebenone whereas invasomes showed higher penetration of azelaic acid. Ex vivo study using a fluorescent dye (DiI) was performed to understand the differences in the penetration behavior of the three vesicular systems on excised human skin. In vitro cytotoxicity studies on B16F10 melanoma cell lines revealed, when loaded with idebenone, LeciPlex formulations had the superior activity followed by invasomes and liposomes. In vitro antimicrobial study of azelaic acid loaded systems on Propionibacterium acne revealed high antimicrobial activity for DDAB leciplex followed by almost equal activity for invasomes and CTAB LeciPlex followed by liposomes. Whereas antiacne efficacy study in rats for azelaic acid loaded systems, invasomes exhibited the best antiacne efficacy followed by liposomes and LeciPlex.

Topics: Animals; Anti-Infective Agents; Cell Line, Tumor; Chemistry, Pharmaceutical; Dermatologic Agents; Dicarboxylic Acids; Drug Delivery Systems; Female; Humans; Liposomes; Melanoma, Experimental; Propionibacterium acnes; Rats; Rats, Wistar; Skin; Skin Absorption; Ubiquinone

Age-related macular degeneration (AMD) is one of the leading causes of blindness. Degeneration of the retinal pigment epithelium (RPE) is pathognomonic for the disease, and oxidative stress plays an important role in the pathogenesis of this disease. This study investigates potential antiapoptotic and cytoprotective effects of idebenone on cultured RPE cells (ARPE-19) under conditions of oxidative stress.. ARPE-19 cells were treated with 1-100 µM idebenone. Cell viability (MTT assay), induction of intracellular reactive oxygen species (ROS) and histone-associated DNA fragments in mono- and oligonucleosomes, expression of proapoptotic BAX and antiapoptotic Bcl-2 as well as senescence-associated β-galactosidase (SA-β-Gal) activity were investigated under exposure to hydrogen peroxide (H2O2).. Idebenone concentrations from 1 to 20 µM showed no toxic effects on ARPE-19 cells. When cells were treated with H2O2, pretreatment with 5, 7.5, 10, and 20 µM idebenone led to a significant increase in the viability of ARPE-19 cells. In addition, idebenone pretreatment significantly attenuated the induction of SA-β-Gal and intracellular ROS as well as the amount of histone-associated DNA fragments after treatment with H2O2. The reduction of proapoptotic BAX and the elevation of antiapoptotic Bcl-2 under idebenone show that this process is rather mediated by inhibiting H2O2-induced apoptosis, not necrosis.. In this study, idebenone increased survival of ARPE-19 cells and reduced cell death, senescence, and oxidative stress by stabilizing the BAX/Bcl-2 ratio.

Topics: Antioxidants; bcl-2-Associated X Protein; Blotting, Western; Cell Death; Cell Survival; Cells, Cultured; Cellular Senescence; Humans; Hydrogen Peroxide; Oxidants; Oxidative Stress; Proto-Oncogene Proteins c-bcl-2; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Retinal Pigment Epithelium; RNA, Messenger; Ubiquinone

Topics: Child; Dystrophin; Exons; Humans; Male; Muscular Dystrophy, Duchenne; Oligonucleotides; Oxadiazoles; RNA Splicing; Ubiquinone

The expression levels of anoctamin 1 (ANO1, TMEM16A), a calcium-activated chloride channel (CaCC), are significantly increased in several tumors, and inhibition of ANO1 is known to reduce cell proliferation and migration. Here, we performed cell-based screening of a collection of natural products and drug-like compounds to identify inhibitors of ANO1. As a result of the screening, idebenone, miconazole and plumbagin were identified as novel ANO1 inhibitors. Electrophysiological studies showed that idebenone, a synthetic analog of coenzyme Q10, completely blocked ANO1 activity in FRT cells expressing ANO1 without any effect on intracellular calcium signaling and CFTR, a cAMP-regulated chloride channel. The CaCC activities in PC-3 and CFPAC-1 cells expressing abundant endogenous ANO1 were strongly blocked by idebenone. Idebenone inhibited cell proliferation and induced apoptosis in PC-3 and CFPAC-1 cells, but not in A549 cells, which do not express ANO1. These data suggest that idebenone, a novel ANO1 inhibitor, has potential for use in cancer therapy.

Topics: Animals; Anoctamin-1; Antineoplastic Agents; Antioxidants; Apoptosis; Biological Products; Calcium Signaling; Cell Line, Tumor; Cell Proliferation; Chloride Channels; Cystic Fibrosis Transmembrane Conductance Regulator; Humans; Miconazole; Naphthoquinones; Neoplasm Proteins; Rats; Rats, Inbred F344; Ubiquinone

The early stages of the atherosclerotic process are initiated by accumulation of oxidized low-density lipoprotein (oxLDL) and damage to the structure or function of the endothelium. Antioxidant supplementation may be a plausible strategy to prevent atherosclerotic disease by quenching excessive reactive oxidative species. In the present study, we demonstrated that idebenone at suitable concentrations significantly prevented oxLDL-induced endothelial dysfunction. The underlying mechanisms of idebenone included inhibition of oxidative damage, suppression of the down-regulation of Bcl-2 and up-regulation of Bax and cleaved caspase-3 in human umbilical vein endothelial cells (HUVECs) exposed to oxLDL. Moreover, idebenone pretreatment inhibited oxLDL-mediated HUVECs damage by attenuating lipid peroxidation and promoting SOD activity. Finally, pro-incubation with idebenone inhibited mitochondrial dysfunction induced by oxLDL through the mitochondrial-dependent apoptotic pathway and GSK3β/β-catenin signalling pathways. In summary, idebenone is a promising agent in the treatment or prevention of atherosclerosis via inhibiting oxidative stress and improving mitochondrial function.

Topics: Antioxidants; Apoptosis; beta Catenin; Cell Survival; Cells, Cultured; Dose-Response Relationship, Drug; Endothelial Cells; Female; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Humans; Lipoproteins, LDL; Mitochondria; Signal Transduction; Treatment Outcome; Ubiquinone

Topics: Adolescent; DNA, Mitochondrial; Humans; Male; Mutation; NADH Dehydrogenase; Optic Atrophy, Hereditary, Leber; Ubiquinone

Friedreich's ataxia (FRDA), the most common hereditary ataxia, is characterized by progressive degeneration of the central and peripheral nervous system, hypertrophic cardiomyopathy and a high risk of diabetes. FRDA is caused by abnormally low levels of frataxin, a highly conserved mitochondrial protein. Drosophila has been previously successfully used to model FRDA in various cell types, including neurons and glial cells. Here, we report the development of a Drosophila cardiac model of FRDA. In vivo heart imaging revealed profound impairments in heart function in frataxin-depleted Drosophila, including a strong increase in end-systolic and end-diastolic diameters and a decrease in fractional shortening (FS). These features, reminiscent of pathological phenotypes in humans, are fully rescued by complementation with human frataxin, suggesting conserved cardiac functions of frataxin between the two organisms. Oxidative stress is not a major factor of heart impairment in frataxin-depleted flies, suggesting the involvement of other pathological mechanisms notably mitochondrial respiratory chain (MRC) dysfunction. Accordingly, we report that methylene blue (MB), a compound known to act as an alternative electron carrier that bypasses mitochondrial complexes I-III, was able to prevent heart dysfunction. MB also partially rescued the phenotype when administered post-symptomatically. Analysis of MB derivatives demonstrates that only compounds with electron carrier properties are able to prevent the heart phenotype. Thus MB, a compound already used for several clinical applications, appears promising for the treatment of the heart dysfunctions that are a major cause of death of FRDA patients. This work provides the grounds for further evaluation of MB action in mammals.

Topics: Animals; Cardiotonic Agents; Disease Models, Animal; Drosophila melanogaster; Drosophila Proteins; Drug Evaluation, Preclinical; Frataxin; Friedreich Ataxia; Gene Knockdown Techniques; Humans; Iron-Binding Proteins; Male; Methylene Blue; RNA Interference; Ubiquinone

The current study investigated the neuroprotective activity of idebenone against pilocarpine-induced seizures and hippocampal injury in rats. Idebenone is a ubiquinone analog with antioxidant, and ATP replenishment effects. It is well tolerated and has low toxicity. Previous studies reported the protective effects of idebenone against neurodegenerative diseases such as Friedreich's ataxia and Alzheimer's disease. So far, the efficacy of idebenone in experimental models of seizures has not been tested. To achieve this aim, rats were randomly distributed into six groups. Two groups were treated with either normal saline (0.9 %, i.p., control group) or idebenone (200 mg/kg, i.p., Ideb200 group) for three successive days. Rats of the other four groups (P400, Ideb50 + P400, Ideb100 + P400, and Ideb200 + P400) received either saline or idebenone (50, 100, 200 mg/kg, i.p.) for 3 days, respectively followed by a single dose of pilocarpine (400 mg/kg, i.p.). All rats were observed for 6 h post pilocarpine injection. Latency to the first seizure, and percentages of seizures and survival were recorded. Surviving animals were sacrificed, and the hippocampal tissues were separated and used for the measurement of lipid peroxides, total nitrate/nitrite, glutathione and DNA fragmentation levels, in addition to catalase and Na(+), K(+)-ATPase activities. Results revealed that in a dose-dependent manner, idebenone (100, 200 mg/kg) prolonged the latency to the first seizure, elevated the percentage of survival and diminished the percentage of pilocapine-induced seizures in rats. Significant increases in lipid peroxides, total nitrate/nitrite, DNA fragmentation levels and catalase activity, in addition to a significant reduction in glutathione level and Na(+), K(+)-ATPase activity were observed in pilocarpine group. Pre-administration of idebenone (100, 200 mg/kg, i.p.) to pilocarpine-treated rats, significantly reduced lipid peroxides, total nitrate/nitrite, DNA fragmentation levels, and normalized catalase activity. Moreover, idebenone prevented pilocarpine-induced detrimental effects on brain hippocampal glutathione level, and Na(+), K(+)-ATPase enzyme activity in rats. Data obtained from the current investigation emphasized the critical role of oxidative stress in induction of seizures by pilocarpine and elucidated the prominent neuroprotective and antioxidant activities of idebenone in this model.

Topics: Animals; Antioxidants; DNA Damage; Glutathione; Hippocampus; Male; Malondialdehyde; Neuroprotective Agents; Pilocarpine; Rats; Rats, Sprague-Dawley; Seizures; Sodium-Potassium-Exchanging ATPase; Ubiquinone

In this study we prepared solid lipid nanoparticles (SLN), by the phase inversion temperature (PIT) method, using cetyl palmitate as solid lipid and three different non-ionic emulsifiers of the polyoxyethylene ethers family (ceteth-20, isoceteth-20, oleth-20). These SLN were loaded with different amount of idebenone (IDE), an antioxidant drug useful in the treatment of neurodegenerative diseases and skin oxidative damages. The differential scanning calorimetry (DSC) was employed to evaluate the effects of the different emulsifiers and the different amounts of drug loaded on the thermotropic behavior of SLN and to investigate how the drug was arranged into these nanoparticles. The IDE seemed to be located into different regions of the SLN depending on its concentration and on the surfactant used. The results of this study suggest that the calorimetric studies performed on SLN could provide valuable information to optimize SLN design and drug release from these carriers.

Topics: Antioxidants; Calorimetry, Differential Scanning; Drug Carriers; Drug Compounding; Drug Liberation; Drug Stability; Ethers; Microscopy, Electron, Transmission; Molecular Structure; Nanoparticles; Palmitates; Particle Size; Polyethylene Glycols; Surface Properties; Surface-Active Agents; Transition Temperature; Ubiquinone

We report a case of a young Chinese male presenting with sequential, painless, bilateral visual loss in Hong Kong. He was diagnosed to have Leber's hereditary optic neuropathy with genetic workup showing G11778A mutation with over 80% heteroplasmy. He was started on idebenone treatment 11 months after onset of the binocular disease. To our best knowledge, this is the first case of Leber's hereditary optic neuropathy treated with idebenone in Hong Kong. The recent evidence of the diagnosis and treatment of this devastating disease is reviewed.

Topics: Adolescent; Antioxidants; Diagnosis, Differential; Hong Kong; Humans; Male; Optic Atrophy, Hereditary, Leber; Ubiquinone; Visual Acuity

Friedreich's ataxia (FRDA), the most common inherited ataxia, is a neurodegenerative disease caused by a reduction in the levels of the mitochondrial protein frataxin, the function of which remains a controversial matter. Several therapeutic approaches are being developed to increase frataxin expression and reduce the intramitochondrial iron aggregates and oxidative damage found in this disease. In this study, we tested separately the response of a Drosophila RNAi model of FRDA (Llorens et al., 2007) to treatment with the iron chelator deferiprone (DFP) and the antioxidant idebenone (IDE), which are both in clinical trials. The FRDA flies have a shortened life span and impaired motor coordination, and these phenotypes are more pronounced in oxidative stress conditions. In addition, under hyperoxia, the activity of the mitochondrial enzyme aconitase is strongly reduced in the FRDA flies. This study reports that DFP and IDE improve the life span and motor ability of frataxin-depleted flies. We show that DFP eliminates the excess of labile iron in the mitochondria and thus prevents the toxicity induced by iron accumulation. IDE treatment rescues aconitase activity in hyperoxic conditions. These results validate the use of our Drosophila model of FRDA to screen for therapeutic molecules to treat this disease.

Topics: Aconitate Hydratase; Animals; Antioxidants; Deferiprone; Disease Models, Animal; Drosophila; Frataxin; Friedreich Ataxia; Hyperoxia; Iron; Iron-Binding Proteins; Mitochondria; Mutation; Oxidative Stress; Phenotype; Pyridones; Ubiquinone

Oxidative stress and mitochondrial dysfunction appear to contribute to neurodegenerative processes during multiple sclerosis (MS). Thus, antioxidants may represent a therapeutic option for MS. The antioxidant idebenone was proven to be beneficial in Friedreich's ataxia and Leber's hereditary optic neuropathy, two disorders caused by mitochondrial alterations. Here we showed that idebenone protected neuronal HT22 cells from glutamate-induced death in vitro. However, in experimental autoimmune encephalomyelitis, idebenone failed to affect disease incidence or onset when applied preventively, or to reduce disease severity when applied therapeutically. Histopathological examination of CNS from idebenone treated mice showed no improvement in inflammation, demyelination, or axonal damage. Thus, we hypothesize that idebenone treatment will likely not benefit patients with MS.

Topics: Animals; Antioxidants; Chronic Disease; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Hippocampus; Inflammation; Mice; Mice, Inbred C57BL; Neurons; Severity of Illness Index; Ubiquinone

The aim of this study was to investigate the toxic impacts of titanium dioxide nanoparticles (TiO₂-NPs) on rat kidneys and the possible prophylactic role of either quercetin or idebenone. TiO₂-NPs were administered orally at either 600 mg or 1 g/kg body weight for 5 consecutive days to evaluate dose-dependent toxicity referred to the OECD guidelines for testing of chemicals. The results showed that administration of either low or high repeated doses of TiO₂-NPs to rats significantly increases serum kideney function biomarkers (urea, creatinine and uric acid) as well as increases in serum glucose and serum immuno- inflammatory biomarkers including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), immunoglobin g (IGg), vascular endothelial growth factor (VEGF, angiogenic factor) and nitric oxide (NO) with a concomitant decrease in renal GSH content versus normal control values. The increase in these biomarkers was more evident in rats intoxicated with high TiO₂-NPs repeated doses. Oral co- administration of either quercetin or idebenone (each 200mg/Kg body weight) daily for three weeks to rats intoxicated by either of the two doses markedly ameliorated TiO₂-NPs induced alteration in the above biomarkers. The prophylactic impacts of both agents on biochemical markers were more pronounced in rats received low TiO₂-NPs repeated doses. The biochemical investigation was supported by histological examination. In conclusion, The data showed the severity in renotoxicity of TiO₂-NPs was dose-dependent and the protective effect of quercetin and idebenone may be related to their antioxidant and anti-inflammatory properties.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Blood Glucose; Creatinine; Cytokines; Dose-Response Relationship, Drug; Inflammation Mediators; Kidney Diseases; Male; Metal Nanoparticles; Particle Size; Quercetin; Rats; Titanium; Ubiquinone; Urea

An aim of the study was to assess the severity of asthenic syndrome, emotional disorders and quality of life indicators in post stroke patients treated with idebenone (noben). We studied 35 patients aged from 47 to 76 years, mean age 58,85±7,99 years, 21 men and 14 women. The time after stroke was 1-8 years (mean 2,63±1,51 years). The duration of follow-up was 6 months. Patients were examined at baseline and 3 and 6 months after treatment with noben in dose 90 mg daily (30 mg 3 times a day). Patients were examined clinically, the following scales were used as well: the Scandinavian stroke scale, the modified MFIS-21, the hospital anxiety and depression scale (HADS) and EQ5D including VAS. It has been shown that asthenic syndrome negatively influenced quality of life and emotional sphere thus impeding the recovery of daily activities. The follow-up study revealed that the treatment with idebenone in dose 90 mg daily decreased the severity of asthenia and emotional disorders and significantly improved quality of life.

Topics: Affective Symptoms; Aged; Aged, 80 and over; Antioxidants; Female; Humans; Male; Middle Aged; Quality of Life; Severity of Illness Index; Stroke; Ubiquinone

Two new aza analogues of the neuroprotective agent idebenone have been synthesized and characterized. Their antioxidant activity, and ability to augment ATP levels have been evaluated in several different cell lines having suboptimal mitochondrial function. Both compounds were found to be good ROS scavengers, and to protect the cells from oxidative stress induced by glutathione depletion. The compounds were more effective than idebenone in neurodegenerative disease cells. These novel pyrimidinol derivatives were also shown to augment ATP levels in coenzyme Q(10)-deficient human lymphocytes. The more lipophilic side chains attached to the pyrimidinol redox core in these compounds resulted in less inhibition of the electron transport chain and improved antioxidant activity.

Topics: Adenosine Triphosphate; Animals; Antioxidants; Cattle; Cell Line; Cell Survival; Drug Design; Glutathione; Humans; Lymphocytes; Mitochondria; Multienzyme Complexes; NADH, NADPH Oxidoreductases; Neurodegenerative Diseases; Neuroprotective Agents; Pyrimidines; Reactive Oxygen Species; Ubiquinone

We have studied the effects of idebenone on mitochondrial function in cybrids derived from one normal donor (HQB17) and one patient harboring the G3460A/MT-ND1 mutation of Leber's Hereditary Optic Neuropathy (RJ206); and in XTC.UC1 cells bearing a premature stop codon at amino acid 101 of MT-ND1 that hampers complex I assembly. Addition of idebenone to HQB17 cells caused mitochondrial depolarization and NADH depletion, which were inhibited by cyclosporin (Cs) A and decylubiquinone, suggesting an involvement of the permeability transition pore (PTP). On the other hand, addition of dithiothreitol together with idebenone did not cause PTP opening and allowed maintenance of the mitochondrial membrane potential even in the presence of rotenone. Addition of dithiothreitol plus idebenone, or of idebenol, to HQB17, RJ206 and XTC.UC1 cells sustained membrane potential in intact cells and ATP synthesis in permeabilized cells even in the presence of rotenone and malonate, and restored a good level of coupled respiration in complex I-deficient XTC.UC1 cells. These findings demonstrate that idebenol can feed electrons at complex III. If the quinone is maintained in the reduced state, a task that in some cell types appears to be performed by dicoumarol-sensitive NAD(P)H:quinone oxidoreductase 1 [Haefeli et al. (2011) PLoS One 6, e17963], electron transfer to complex III may allow reoxidation of NADH in complex I deficiencies.

Topics: Adenosine Triphosphate; Animals; Antioxidants; Cell Respiration; Cells, Cultured; Dithiothreitol; Drug Evaluation, Preclinical; Energy Metabolism; Membrane Potential, Mitochondrial; Mice; Mitochondria, Liver; Oxygen Consumption; Ubiquinone

Idebenone (IDB) is a synthetic antioxidant and analog of coenzyme Q10. The percutaneous permeation of IDB was investigated in guinea pig skin after application of different formulations. The enhancing effects of various formulations [nanostructured lipid carriers (NLCs), nanoemulsion (NE), or oil solution] on the permeation of IDB were evaluated using ex vivo guinea pig skins. Furthermore, stability of different formulations and in which chemical stability of IDB was determined during storage. Permeation experiments revealed that formulations varied in their ability to enhance the skin permeation of IDB. For NLC formulation, the cumulative amount of IDB in the epidermis, dermis, and acceptor medium of diffusion cells was approximately threefold more than NE or oil solution at the end of 24-h experiment. No significant difference between NE and oil solution was observed in the enhancement of penetration efficacy of IDB. Different formulations resulted in stability with different properties. NLC formulation revealed preferentially more stable than NE. The residual percentage of IDB loaded in NLCs, NE, and oil solution was 90.1%, 65.4%, and 51.3%, respectively, when stored at 40°C under 75% RH and 3,000 lx light conditions for 180 days. The results obtained here demonstrated that the abilities of NLCs to improve the chemical stability of IDB and enhance the skin permeation are much better than NE and oil solution. These suggest that NLCs containing IDB have significant potential use for skin care as an alternative topical formulation.

Topics: Animals; Antioxidants; Drug Carriers; Drug Stability; Female; Guinea Pigs; Lipids; Nanostructures; Skin Absorption; Ubiquinone

Friedreich ataxia (FA) is the most frequent type of autosomal recessive cerebellar ataxia, occurring at a mean age of 16 years. Nearly 98% of patients with FA present with homozygous GAA expansions in the FXN gene. The remaining patients are compound heterozygous for an expansion and a point mutation. Patients who are compound heterozygous for an exonic deletion and an expansion are exquisitely rare.. To describe 6 patients affected with FA due to an exonic deletion mutation (FAexdel) and to compare these 6 patients with FAexdel with 46 patients consecutively diagnosed with typical FA due to homozygous GAA expansion and whose small expansions were within the same range as that of the expansions of the patients with FAexdel.. Description of a series.. Academic research.. Six patients with FAexdel and 46 patients with typical FA.. FXN gene analysis, including assessments of GAA expansion and exon sequencing and determination of exonic copy numbers using multiplex ligation-dependent probe amplification.. We identified 6 patients with FA who presented with the combination of 1 GAA expansion and 1 FXN exonic deletion. The mean (SD) age at onset of the disease was earlier for patients with FAexdel (7 [4] years [range, 3-12 years]) than for patients with typical FA (15 [5] years [range, 6-30 years]) (P = .001), and the median time to confinement to wheelchair was shorter for patients with FAexdel (20 years) than for patients with typical FA (28 years) (P = .002). There was no difference between the mean (SD) size of the expansion for the patients with FAexdel (780 [256] GAA triplet repeat sequences [range, 340-1070 GAA triplet repeat sequences]) and the mean (SD) size of the short expansion for the patients with typical FA (634 [163] GAA triplet repeat sequences [range, 367-1000 GAA triplet repeat sequences]) (P = .10). The mean disease duration before becoming wheelchair bound was shorter for patients with FAexdel (9 years) than for patients with typical FA (13 years), and the incidence of cardiomyopathy was higher for patients with FAexdel (84%) than for patients with typical FA (68%). However, these differences were not significant, probably owing to the small size of the FAexdel group. The other extraneurological signs, such as scoliosis or diabetes mellitus, were particularly frequently observed in the FAexdel group. One patient presented at 9 years of age with severe angina and marked cardiomyopathy that confined her to a wheelchair. Three patients had disabling autonomic disturbances. It appears that exonic deletion significantly contributes to the clinical picture of patients with FA.. Friedreich ataxia due to an exonic deletion mutation corresponds to an early onset and severe variant of FA. FXN should be investigated for exonic deletion in patients with early-onset FA in which only 1 GAA expansion without a point mutation is found. Patients with FAexdel have to be carefully observed using cardiological, orthopaedic, endocrinological, gastroenterological, and ophthalmological data. Friedreich ataxia due to an exonic deletion mutation should be suspected in young patients presenting with severe scoliosis.

Topics: Adult; Antioxidants; Cardiomyopathies; Disease Progression; Electromyography; Exons; Family Health; Female; Frataxin; Friedreich Ataxia; Humans; Iron-Binding Proteins; Magnetic Resonance Imaging; Male; Middle Aged; Sequence Deletion; Trinucleotide Repeat Expansion; Ubiquinone

Digitonin solubilizes mitochondrial membrane, breaks the integrity of the respiratory chain and releases two mobile redox-active components: coenzyme Q (CoQ) and cytochrome c (cyt c). In the present study we report the inhibition of glycerol-3-phosphate- and succinate-dependent oxygen consumption rates by digitonin treatment. Our results show that the inhibition of oxygen consumption rates is recovered by the addition of exogenous synthetic analog of CoQ idebenone (hydroxydecyl-ubiquinone; IDB) and cyt c. Glycerol-3-phosphate oxidation rate is recovered to 148 % of control values, whereas succinate-dependent oxidation rate only to 68 %. We find a similar effect on the activities of glycerol-3-phosphate and succinate cytochrome c oxidoreductase. Our results also indicate that succinate-dependent oxidation is less sensitive to digitonin treatment and less activated by IDB in comparison with glycerol-3-phosphate-dependent oxidation. These findings might indicate the different mechanism of the electron transfer from two flavoprotein-dependent dehydrogenases (glycerol-3-phosphate dehydrogenase and succinate dehydrogenase) localized on the outer and inner face of the inner mitochondrial membrane, respectively.

Topics: Animals; Cytochromes c; Digitonin; Disease Models, Animal; Dose-Response Relationship, Drug; Glycerolphosphate Dehydrogenase; Glycerophosphates; Hyperthyroidism; Kinetics; Male; Mitochondria, Liver; Mitochondrial Membranes; Oxidation-Reduction; Oxygen Consumption; Rats; Rats, Wistar; Recovery of Function; Succinate Cytochrome c Oxidoreductase; Succinic Acid; Ubiquinone

The aim of this study was to evaluate in vitro the permeation of the antioxidant agent Idebenone (IDE) loaded into solid lipid nanoparticles (SLN) across MDCKII-MDR1 cell monolayer, selected as an in vitro model of the Blood Brain Barrier (BBB). SLN were prepared using cetyl palmitate as solid lipid and different non-ionic surfactants, oleth-20, ceteth-20 and isoceth-20, by the phase inversion temperature (PIT) technique. The resulting SLN showed physiological pH and osmolarity values, a mean particle diameter in the range of 33-63 nm, a single peak in size distribution, and a zeta potential ranging from +3.14 to -2.89 mV. When incubating these SLN in Simulated Body Fluid (SBF), the particle size was maintained for all samples throughout the study. IDE permeability across MDCKII-MDR1 cell monolayers from the SLN under investigation was 0.40-0.53 fold lower than free IDE and no significant difference was observed comparing IDE permeation from all the SLN tested. It is noteworthy that IDE loading into SLN avoided the use of an organic solvent to solubilize IDE, a poor water soluble compound, allowing the parenteral administration of this drug in aqueous vehicles. Furthermore, the results of in vitro transport studies, performed using fluorescein-dextran 4000 (FD4) and diazepam (DZ) as markers of the paracellular pathway and the transcellular pathway, respectively, pointed out that IDE could permeate via a transcellular pathway. Therefore, these novel nanocarriers could be regarded as a promising strategy to design delivery systems for IDE administration to the brain, deserving further investigations under in vivo conditions.

Topics: Animals; Antioxidants; Blood-Brain Barrier; Diffusion; Dogs; Lipids; Materials Testing; Nanocapsules; Ubiquinone

Short-chain quinones have been investigated as therapeutic molecules due to their ability to modulate cellular redox reactions, mitochondrial electron transfer and oxidative stress, which are pathologically altered in many mitochondrial and neuromuscular disorders. Recently, we and others described that certain short-chain quinones are able to bypass a deficiency in complex I by shuttling electrons directly from the cytoplasm to complex III of the mitochondrial respiratory chain to produce ATP. Although this energy rescue activity is highly interesting for the therapy of disorders associated with complex I dysfunction, no structure-activity-relationship has been reported for short-chain quinones so far. Using a panel of 70 quinones, we observed that the capacity for this cellular energy rescue as well as their effect on lipid peroxidation was influenced more by the physicochemical properties (in particular logD) of the whole molecule than the quinone moiety itself. Thus, the observed correlations allow us to explain the differential biological activities and therapeutic potential of short-chain quinones for the therapy of disorders associated with mitochondrial complex I dysfunction and/or oxidative stress.

Topics: Adenosine Triphosphate; Animals; Antioxidants; Cell Line; Chemical Phenomena; Electron Transport Complex I; Humans; Lipid Peroxidation; Mitochondrial Diseases; Rats; Ubiquinone

Idebenone (IDE), a synthetic derivative of ubiquinone, shows a potent antioxidant activity that could be beneficial in the treatment of skin oxidative damages. In this work, the feasibility of targeting IDE into the upper layers of the skin by topical application of IDE-loaded solid lipid nanoparticles (SLN) was evaluated. SLN loading different amounts of IDE were prepared by the phase inversion temperature method using cetyl palmitate as solid lipid and three different non-ionic surfactants: ceteth-20, isoceteth-20 and oleth-20. All IDE loaded SLN showed a mean particle size in the range of 30-49 nm and a single peak in size distribution. In vitro permeation/penetration experiments were performed on pig skin using Franz-type diffusion cells. IDE penetration into the different skin layers depended on the type of SLN used while no IDE permeation occurred from all the SLN under investigation. The highest IDE content was found in the epidermis when SLN contained ceteth-20 or isoceteth-20 as surfactant while IDE distribution into the upper skin layers depended on the amount of IDE loaded when oleth-20 was used as surfactant. These results suggest that the SLN tested could be an interesting carrier for IDE targeting to the upper skin layers.

Topics: Animals; Antioxidants; Cetomacrogol; Drug Delivery Systems; Ethers; Feasibility Studies; Lipids; Nanoparticles; Particle Size; Permeability; Plant Oils; Polyethylene Glycols; Skin Absorption; Surface-Active Agents; Swine; Tissue Distribution; Ubiquinone

Idebenone is a benzoquinone analog that is used in the treatment of several neurological disorders including Friedreich's ataxia. It was found that the reaction of idebenone with 2-cyanoacetamide under alkaline conditions generates fluorescent products, and the reaction was considered to proceed via Craven's reaction. The reaction mixture from idebenone gave fluorescence with excitation and emission maximum wavelengths at 358 nm and 409 nm, respectively. It was adopted for HPLC with post-column fluorescence derivatization of idebenone. Idebenone in the plasma showed a linear response in the range of 0.5-32 ng (25-1600 ng/mL), and the quantitation limit (S/N=10) was 12.5 ng/mL. The detection limit (S/N=3) of the standard solution of idebenone was 0.1 ng. The HPLC system was applied to the human blood plasma obtained by finger prick. The plasma sample obtained by finger prick gave a similar chromatogram to that of venous blood obtained by venipuncture.

Topics: Chromatography, High Pressure Liquid; Humans; Nitriles; Spectrometry, Fluorescence; Ubiquinone

The knowledge of the interactions between solid lipid nanoparticles (SLN) and cell membranes is important to develop effective carrier systems for drug delivery applications. Loading idebenone (IDE), an antioxidant drug useful in the treatment of neurodegenerative diseases, into SLN improves IDE antioxidant activity in in vitro biological studies, but the mechanism by which IDE permeation through the blood-brain barrier (BBB) occurs are still unclear. Therefore, in this research, unloaded and IDE loaded SLN interaction with biomembrane models, consisting of dimyristoylphosphatidylcholine multilamellar vesicles (MLV), were studied by differential scanning calorimetry (DSC). In the experiments performed, unloaded and IDE loaded SLN where incubated with the biomembrane models and their interactions were evaluated through the variations in their calorimetric curves. The results of our DSC studies indicated that the SLN under investigation were able to go inside the phospholipid bilayers with a likely localization in the outer bilayers of the MLV from where they moved toward the inner layers by increasing the contact time between SLN and MLV. Furthermore, IDE loaded SLN were able to release IDE into the biomembrane model, thus facilitating IDE penetration into the bilayers while free IDE showed only a low ability to interact with this model of biomembranes. Our results suggest that these SLN could be regarded as a promising drug delivery system to improve IDE bioavailability and antioxidant activity.

Topics: Antioxidants; Biological Availability; Calorimetry; Calorimetry, Differential Scanning; Dimyristoylphosphatidylcholine; Drug Delivery Systems; Lipids; Membranes; Membranes, Artificial; Nanoparticles; Phospholipids; Ubiquinone

Antioxidants have been shown to protect against aminoglycoside-induced hearing loss. Mitoquinone (MitoQ) is a mitochondria-targeted derivative of the antioxidant ubiquinone. MitoQ is attached to a lipophilic triphenylphosphonium (TPP) cation, which enables its accumulation inside the mitochondria several hundred-fold over the untargeted antioxidant. The goals of this study were to determine if MitoQ attenuates gentamicin-induced activation of caspase-3/7 activity as a marker of apoptosis and to determine if MitoQ impacts aminoglycoside antimicrobial efficacy.. Prospective and controlled.. Antibiotic efficacy and minimum inhibitory concentrations (MICs) of gentamicin against three strains each of Staphylococcus aureus, Haemophilus influenzae, and Pseudomonas aeruginosa were evaluated with and without MitoQ using broth dilution methods. Apoptosis was assessed by caspase-3/7 activity in untreated HEI-OC1 cells and cells exposed to 2 mM gentamicin for 24 hours, with and without a 24-hour preincubation with 0.5 μM each of MitoQ, idebenone (an untargeted ubiquinone), or decylTPP (positive control).. Gentamicin MICs for P aeruginosa and H influenzae were not affected by MitoQ at pharmacological levels. MICs for S aureus were enhanced by MitoQ. Cell viability was significantly lower in the gentamicin-treated cells. A significant increase in caspase-3/7 activity was observed in cells treated with gentamicin or with idebenone + gentamicin (P = .005). Preincubation with MitoQ decreased the gentamicin-induced apoptosis of HEI-OC1 cells to a greater extent compared to idebenone (P = .002).. MitoQ attenuates gentamicin-induced apoptosis in HEI-OC1 cells and does not compromise gentamicin antibiotic efficacy. MitoQ holds promise as a means of preventing aminoglycoside ototoxicity.

Topics: Analysis of Variance; Apoptosis; Caspase 3; Cell Survival; Gentamicins; Haemophilus influenzae; Microbial Sensitivity Tests; Mitochondria; Organophosphorus Compounds; Prospective Studies; Pseudomonas aeruginosa; Staphylococcus aureus; Ubiquinone

We investigated the damage caused by oxidative stress using the yeast Saccharomyces cerevisiae as a model biological system. After inducing oxidative stress with menadione, we were able to evaluate the extent of cellular oxidative stress by utilizing 2',7'-dichlorofluorescein diacetate (DCFH-DA) as a marker of the presence of reactive oxygen species. Cells were grown on different carbon sources in order to compare fermentative and oxidative metabolism. Under these conditions we evaluated the effectiveness of idebenone (2,3-dimethoxy-5-methyl-6-(10- hydroxydecyl)-1,4-benzoquinone) as a molecule that could relieve menadione-induced growth inhibition in Saccharomyces cerevisiae.

Topics: Antioxidants; Fermentation; Fluoresceins; Oxidative Stress; Reactive Oxygen Species; Saccharomyces cerevisiae; Ubiquinone; Vitamin K 3

Leber's hereditary optic neuropathy (LHON) is an inherited disease caused by mutations in complex I of the mitochondrial respiratory chain. The disease is characterized by loss of central vision due to retinal ganglion cell (RGC) dysfunction and optic nerve atrophy. Despite progress towards a better understanding of the disease, no therapeutic treatment is currently approved for this devastating disease. Idebenone, a short-chain benzoquinone, has shown promising evidence of efficacy in protecting vision loss and in accelerating recovery of visual acuity in patients with LHON. It was therefore of interest to study suitable LHON models in vitro and in vivo to identify anatomical correlates for this protective activity. At nanomolar concentrations, idebenone protected the rodent RGC cell line RGC-5 against complex I dysfunction in vitro. Consistent with the reported dosing and observed effects in LHON patients, we describe that in mice, idebenone penetrated into the eye at concentrations equivalent to those which protected RGC-5 cells from complex I dysfunction in vitro. Consequently, we next investigated the protective effect of idebenone in a mouse model of LHON, whereby mitochondrial complex I dysfunction was caused by exposure to rotenone. In this model, idebenone protected against the loss of retinal ganglion cells, reduction in retinal thickness and gliosis. Furthermore, consistent with this protection of retinal integrity, idebenone restored the functional loss of vision in this disease model. These results support the pharmacological activity of idebenone and indicate that idebenone holds potential as an effective treatment for vision loss in LHON patients.

Topics: Administration, Oral; Animals; Antioxidants; Cell Line; Cell Survival; Disease Models, Animal; Drug Administration Schedule; Electron Transport Complex I; Humans; Intravitreal Injections; Male; Mice; Mitochondria; Mutation; Optic Atrophy, Hereditary, Leber; Retinal Ganglion Cells; Rotenone; Ubiquinone; Visual Acuity

Topics: Antioxidants; Humans; Male; Optic Atrophy; Optic Disk; Ubiquinone; Visual Fields; Wolfram Syndrome; Young Adult

The present study aims to clarify the protective effect of supplementation with some antioxidants, such as idebenone (200 mg/kg, ip), melatonin (10 mg/kg, ip) and arginine (200 mg/kg, ip) and their combination, on liver function (T. protein, albumin, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase), energetic parameters (adenosine triphosphate, adenosine diphosphate, adenosine monophosphate, inorganic phosphate, total adenylate, adenylate energy charge and potential phosphate). The effect on glycolytic and glycogenolytic enzymes (glucose, glycogen, glycogen phosphorylase, pyruvate kinase and phosphofructokinase against hypoxia) was also studied. The drugs were administered 24 and 1 h prior sodium nitrite intoxication. All biochemical parameters were estimated 1 h after sodium nitrite injection. Injection of sodium nitrite (75 mg/kg, sc) produced a significant disturbance in all biochemical parameters of liver function, energetic parameters and glycolytic and glycogenolytic enzymes. Hepatic damage was confirmed by histopathological examination of the liver as compared to controls. The marked changes in hepatic cells induced by sodium nitrite were completely abolished by pretreatment with the drug combination, suggesting potential protection against sodium nitrite-induced hypoxia. It could be concluded that a combination of both idebenone and melatonin or idebenone and arginine provides potential protection against sodium nitrite-induced hypoxia by improving biochemical parameters and preserving liver histology.

Topics: Animals; Antioxidants; Arginine; Chemical and Drug Induced Liver Injury; Cytoprotection; Dietary Supplements; Disease Models, Animal; Drug Therapy, Combination; Energy Metabolism; Hypoxia; Liver; Male; Melatonin; Oxidative Stress; Rats; Reactive Oxygen Species; Sodium Nitrite; Time Factors; Ubiquinone

An 18-year-old lady had presented to us with insidious onset progressive gait ataxia of 5-year duration. Her sister had similar complaints and type 1 diabetes mellitus. Examination revealed, gait ataxia, impaired tandem gait, babinski sign and severe swaying on testing for Romberg's sign. All deep tendon reflexes were exaggerated. On investigations, there was no evidence for diabetes mellitus or nutritional deficiencies. Electrocardiogram and echocardiogram were normal. Magnetic spine resonance showed marked atrophy of cervical cord with normal cerebellum. The genetic testing disclosed expanded GAA repeat length on both alleles of FXN gene. The GAA repeat length on both alleles was much less than mean length observed in Friedreich's ataxia. This case highlights how strongly the genotype influences the neurological and systemic manifestations as well as severity of disease in Friedreich's ataxia.

Topics: Adolescent; Antioxidants; Atrophy; Exercise Therapy; Female; Frataxin; Friedreich Ataxia; Genotype; Humans; Iron-Binding Proteins; Magnetic Resonance Imaging; Phenotype; Reflex, Babinski; Spinal Cord; Trinucleotide Repeat Expansion; Ubiquinone

Increasing the lipophilicity and/or amphiphilicity of drugs is a potential strategy to improve loading and retention in lipid-based carriers, such as liposomes or lipid nanoparticles.. Idebenone (IDE), an antioxidant compound structurally related to coenzyme Q, or amphiphilic prodrugs of IDE with lipoamino acids, were loaded in neutral or negatively charged SUVET unilamellar liposomes to achieve a controlled release.. Technological properties of these systems in the presence of loaded drugs were evaluated in terms of vesicle size, homogeneity, and surface charge, as well as in vitro drug release. The effect of liposomal carrier on the in vitro antioxidant activity of the prodrugs was evaluated from using different biochemical assays on murine astrocyte cultures.. Although a good loading efficiency was obtained, liposomes were not able to release efficiently the encapsulated drugs, at least in the in vitro serum-free conditions used for the biological tests. However, in some cases, such as in the comet assay, encapsulation of IDE prodrugs in liposomes allowed for the improvement of their protective activity, compared to the free compounds, against the oxidative damage induced on cultured astrocytes.. Experimental in vitro data suggested that the high affinity shown by these lipophilic IDE derivatives for the liposomal carriers negatively affect their biological activity.

Topics: Animals; Antioxidants; Astrocytes; Cells, Cultured; Comet Assay; DNA; Drug Carriers; Liposomes; Prodrugs; Rats; Rats, Wistar; Reactive Oxygen Species; Ubiquinone

Iron chelators are a new therapeutical approach for patients with Friedreich's ataxia, on the basis that oxidative cell damage that occurs in these patients is due to the increasing deposits of mitochondrial iron pools. The objective of the study was to evaluate the effects of the combined therapy of idebenone and low oral doses of deferiprone on the neurological signs and cardiac function parameters. This study was designed as a prospective open-label single-arm study. Twenty Friedreich's ataxia patients were treated with idebenone (20 mg/kg/day) and deferiprone (20 mg/kg/day) for 11 months. Patients were evaluated before the start and throughout the study with the International Cooperative Ataxia Rating Scale (ICARS) scores, echocardiographic measurements and MRI (magnetic resonance imaging) techniques to asses brain iron deposits in the dentate nucleus. No significant differences were observed in total ICARS scores when comparing baseline status and the end of the study in the whole group of patients. Posture and gait scores increased significantly after 11 months of therapy (Wilcoxon's test, p = 0.04) and kinetic function improved significantly (Wilcoxon's test, p = 0.015). Echocardiography data showed a significant reduction of the interventricular septum thickness (Wilcoxon's test, p = 0.04) and in the left ventricular mass index (Wilcoxon's test, p = 0.038) after the start of the therapy. The MRI values in the dentate nucleus showed a statistically significant reduction (Wilcoxon's test p = 0.007) between baseline conditions and after 11 months of the therapy. Combined therapy with idebenone and deferiprone in patients with FDRA indicates a stabilizing effect in neurologic dysfunctions due to an improvement in the kinetic functions, with a worsening of gait and posture scores. Heart hypertrophy parameters and iron deposits in dentate nucleus improved significantly. Combined therapy was well tolerated with mild side effects, apart from the risk of neutropenia and progressive reduction of plasma iron parameters.

Topics: Adolescent; Adult; Antioxidants; Blood Cell Count; Brain Chemistry; Child; Deferiprone; Drug Therapy, Combination; Dysarthria; Female; Friedreich Ataxia; Gait Disorders, Neurologic; Heart Function Tests; Humans; Iron; Iron Chelating Agents; Magnetic Resonance Imaging; Male; Neurologic Examination; Oculomotor Muscles; Prospective Studies; Pyridones; Speech Disorders; Ubiquinone; Ultrasonography; Young Adult

Solid lipid nanoparticles (SLN) are regarded as interesting drug delivery systems and their preparation techniques have gained a great deal of attention.. To evaluate the feasibility of preparing idebenone (IDE) loaded SLN from O/W microemulsions by the phase-inversion temperature (PIT) method. Since SLN have been proposed to improve drug delivery to the brain, IDE was chosen as model drug due to its activity in the treatment of neurodegenerative diseases.. Cetyl palmitate was used as solid lipid to prepare SLN containing two surfactant/cosurfactant mixtures, isoceteth-20/glyceryl oleate (SLN A) and ceteth-20/glyceryl oleate (SLN B) by the PIT method.. All the formulations tested showed a mean particle diameter ranging from 30 to 95 nm and a single peak in size distribution. Stability tests showed that SLN B were more stable than SLN A. IDE release was dependent both on the type of primary surfactant used and the amount of loaded drug. IDE-loaded SLN were effective in inhibiting 2,2'-azobis-(2-amidinopropane)dihydrochloride (APPH)-induced lactic dehydrogenase (LDH) release and reactive oxygen species (ROS) production in primary cultures of astrocytes obtained from rat cerebral cortex. It is noteworthy that SLN B2 (containing ceteth-20 as primary surfactant and 0.7% w/w IDE) were able to prevent entirely both the LDH release and ROS production induced by APPH.. The PIT method provided SLN with good technological properties. The tested SLN could be regarded as interesting carriers to overcome the blood brain barrier and increase the efficacy of the loaded drug.

Topics: Animals; Antioxidants; Astrocytes; Blood-Brain Barrier; Cerebral Cortex; Cetomacrogol; Drug Delivery Systems; Drug Stability; Emulsions; Ethylene Glycols; Fatty Alcohols; Glycerides; In Vitro Techniques; Nanoparticles; Palmitates; Particle Size; Rats; Rats, Wistar; Reactive Oxygen Species; Surface-Active Agents; Tissue Distribution; Ubiquinone

Short-chain quinones are described as potent antioxidants and in the case of idebenone have already been under clinical investigation for the treatment of neuromuscular disorders. Due to their analogy to coenzyme Q10 (CoQ10), a long-chain quinone, they are widely regarded as a substitute for CoQ10. However, apart from their antioxidant function, this provides no clear rationale for their use in disorders with normal CoQ10 levels. Using recombinant NAD(P)H:quinone oxidoreductase (NQO) enzymes, we observed that contrary to CoQ10 short-chain quinones such as idebenone are good substrates for both NQO1 and NQO2. Furthermore, the reduction of short-chain quinones by NQOs enabled an antimycin A-sensitive transfer of electrons from cytosolic NAD(P)H to the mitochondrial respiratory chain in both human hepatoma cells (HepG2) and freshly isolated mouse hepatocytes. Consistent with the substrate selectivity of NQOs, both idebenone and CoQ1, but not CoQ10, partially restored cellular ATP levels under conditions of impaired complex I function. The observed cytosolic-mitochondrial shuttling of idebenone and CoQ1 was also associated with reduced lactate production by cybrid cells from mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) patients. Thus, the observed activities separate the effectiveness of short-chain quinones from the related long-chain CoQ10 and provide the rationale for the use of short-chain quinones such as idebenone for the treatment of mitochondrial disorders.

Topics: Adenosine Triphosphate; Animals; Cell Line; Cell Line, Tumor; Cells, Cultured; Female; HEK293 Cells; Hep G2 Cells; Humans; Lactic Acid; Male; Membrane Potential, Mitochondrial; Mice; NAD; NAD(P)H Dehydrogenase (Quinone); Oxidation-Reduction; Quinones; Rats; Rotenone; Ubiquinone

Mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) is a maternally-inherited multisystem disorder. Mitochondrial angiopathy mediated by nitric oxide, a metabolite of L-arginine, is among the proposed pathophysiologic mechanisms of stroke-like episodes (SLEs) in MELAS. There are very few reports on long-term prevention of SLEs with oral L-arginine and idebenone treatment in MELAS adult patients.. A 38-year-old patient with MELAS and SLEs was treated with oral L-arginine and idebenone for 27months. She remained free of attacks throughout the treatment period except when she stopped her treatment on two occasions during which she had recurrent cerebral metabolic attacks. The patient experienced no side effect of treatment with L-arginine and idebenone.. Our observation suggests long-term safety and potential benefit of oral L-arginine and idebenone in the prevention of recurrence of SLEs in adult MELAS patients.

Topics: Administration, Oral; Adult; Antioxidants; Arginine; Drug Combinations; Female; Humans; MELAS Syndrome; Stroke; Time Factors; Treatment Outcome; Ubiquinone

The present study was aimed at investigating the effect and the possible mechanism of idebenone on endogenous glutamate release in nerve terminals of rat cerebral cortex (synaptosomes). Idebenone inhibited the release of glutamate that was evoked by exposing synaptosomes to the K(+) channel blocker 4-aminopyridine (4-AP), and this phenomenon was concentration dependent. Inhibition of glutamate release by idebenone was prevented by chelating extracellular Ca(2+), or by the vesicular transporter inhibitor bafilomycin A1, but was insensitive to DL-threo-beta-benzyl-oxyaspartate, a glutamate transporter inhibitor. Idebenone decreased the depolarization-induced increase in the cytosolic free Ca(2+) concentration ([Ca(2+)](C)),whereas it did not alter the resting synaptosomal membrane potential or 4-AP-mediated depolarization. The inhibitory effect of idebenone on evoked glutamate release was prevented by blocking the Ca(v)2.2 (N-type) and Ca(v)2.1 (P/Q-type) channels, but not by blocking intracellular Ca(2+) release or Na(+)/Ca(2+) exchange. Furthermore, the idebenone effect on 4-AP-evoked Ca(2+) influx and glutamate release was completely abolished by the protein kinase A (PKA) inhibitors, H89 and KT5720. On the basis of these results, it was concluded that idebenone inhibits glutamate release from rat cortical synaptosomes and this effect is linked to a decrease in [Ca(2+)](C) contributed by Ca(2+) entry through presynaptic voltage-dependent Ca(2+) channels and to the suppression of PKA signaling cascade.

Topics: 4-Aminopyridine; Animals; Aspartic Acid; Calcium; Calcium Channel Blockers; Calcium Channels; Calcium Signaling; Carbazoles; Cerebral Cortex; Clonazepam; Cyclic AMP-Dependent Protein Kinases; Dantrolene; Dose-Response Relationship, Drug; Enzyme Inhibitors; Glutamate Plasma Membrane Transport Proteins; Glutamic Acid; Indoles; Isoquinolines; Macrolides; Male; Maleimides; Membrane Potentials; Nerve Endings; omega-Conotoxins; Potassium; Protein Kinase C; Protein Kinase Inhibitors; Pyrroles; Rats; Rats, Sprague-Dawley; Sodium-Calcium Exchanger; Sulfonamides; Synaptosomes; Thiazepines; Ubiquinone

Idebenone is a coenzyme Q10 analog and an antioxidant that has been used clinically to treat Friedreich Ataxia. Being an antioxidant, idebenone could have potential therapeutic potential to treat other neurodegenerative diseases such as Parkinson's disease in which oxidative stress plays a role in their pathogenesis. But whether idebenone can be used to treat Parkinson's disease has not been evaluated. In this study, we found that exposure of the dopaminergic neuroblastoma SHSY-5Y cells to 1-10 μM idebenone for 72 h had no effect on the cell viability revealed by trypan blue exclusion assay and MTT assay. However, cells exposed to 25 μM or higher concentrations of idebenone showed extensive trypan blue-positive staining and significant reduction in cell viability revealed by MTT assay indicating that most of the cells were no longer viable. Idebenone-induced cell death was characterized by genomic DNA fragmentation and accumulation of cytochrome c in the cytosol indicating that the death was apoptotic in nature. In addition, idebenone induced an increase in the total RNA of the pro-apoptosis protein BAX, it also increased the caspase-3 activity in the cell lysates when compared with the untreated control cells or cells exposed to 10 μM or lower concentrations of idebenone. The detrimental effect of idebenone was attenuated by glutathione, an antioxidant, suggesting that oxidative stress contributed to the idebenone-induced cell death. In conclusion, our results suggest that antioxidant idebenone induced apoptosis when used in high concentrations.

Topics: Antioxidants; Apoptosis; Caspase 3; Cell Line, Tumor; Cell Survival; Cytochromes c; DNA Fragmentation; Dopamine; Dose-Response Relationship, Drug; Glutathione; Humans; Neuroblastoma; Tetrazolium Salts; Thiazoles; Time Factors; Trypan Blue; Ubiquinone

Topics: Antioxidants; Humans; Neurodegenerative Diseases; Oxidative Stress; Ubiquinone

Friedreich's ataxia (FRDA) is a mitochondrial rare disease, which molecular origin is associated with defect in the expression of frataxin. The pathological consequences are degeneration of nervous system structures and cardiomyopathy with necrosis and fibrosis, among others.. Using FRDA fibroblasts we have characterized the oxidative stress status and mitochondrial biogenesis. We observed deficiency of MnSOD, increased ROS levels and low levels of ATP. Expression of PGC-1α and mtTFA was increased and the active form of the upstream signals p38 MAPK and AMPK in fibroblasts from two patients. Interestingly, the expression of energetic factors correlated with the natural history of disease of the patients, the age when skin biopsy was performed and the size of the GAA expanded alleles. Furthermore, idebenone inhibit mitochondriogenic responses in FRDA cells.. The induction of mitochondrial biogenesis in FRDA may be a consequence of the mitochondrial impairment associated with disease evolution. The increase of ROS and the involvement of the oxidative phosphorylation may be an early event in the cell pathophysiology of frataxin deficiency, whereas increase of mitochondriogenic response might be a later phenomenon associated to the individual age and natural history of the disease, being more evident as the patient age increases and disease evolves. This is a possible explanation of heart disease in FRDA.

Topics: Adenosine Triphosphate; Adolescent; Adult; Aging; Alleles; AMP-Activated Protein Kinases; Antioxidants; Catalase; Child; Disease Progression; DNA-Binding Proteins; Energy Metabolism; Female; Fibroblasts; Friedreich Ataxia; Gene Expression Regulation; Glutathione Peroxidase; Heat-Shock Proteins; Humans; Male; Middle Aged; Mitochondria; Mitochondrial Proteins; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Reactive Oxygen Species; Signal Transduction; Superoxide Dismutase; Transcription Factors; Trinucleotide Repeats; Ubiquinone

Topics: Burkholderia; Canada; Giant Cell Arteritis; Humans; Multiple Sclerosis; Neurology; Ophthalmology; Optic Atrophy, Hereditary, Leber; Pseudotumor Cerebri; Retinal Artery Occlusion; Societies, Medical; Tissue Plasminogen Activator; Tomography, Optical Coherence; Ubiquinone

Topics: Antioxidants; Female; Humans; Male; Optic Atrophy, Hereditary, Leber; Placebos; Ubiquinone

Topics: Antioxidants; Female; Humans; Male; Optic Atrophy, Hereditary, Leber; Placebos; Ubiquinone

Heterozygous loss-of-function mutation of the human gene for the mitochondrial protease HtrA2 has been associated with increased risk to develop mitochondrial dysfunction, a process known to contribute to neurodegenerative disorders such as Huntington's disease (HD) and Parkinson's disease (PD). Knockout of HtrA2 in mice also leads to mitochondrial dysfunction and to phenotypes that resemble those found in neurodegenerative disorders and, ultimately, lead to death of animals around postnatal day 30. Here, we show that Idebenone, a synthetic antioxidant of the coenzyme Q family, and Resveratrol, a bioactive compound extracted from grapes, are both able to ameliorate this phenotype. Feeding HtrA2 knockout mice with either compound extends lifespan and delays worsening of the motor phenotype. Experiments conducted in cell culture and on brain tissue of mice revealed that each compound has a different mechanism of action. While Idebenone acts by downregulating the integrated stress response, Resveratrol acts by attenuating apoptosis at the level of Bax. These activities can account for the delay in neuronal degeneration in the striata of these mice and illustrate the potential of these compounds as effective therapeutic approaches against neurodegenerative disorders such as HD or PD.

Topics: Animals; Cell Count; Gene Expression Regulation; Gene Knockout Techniques; High-Temperature Requirement A Serine Peptidase 2; Longevity; Mice; Mitochondrial Proteins; Motor Activity; Neostriatum; Oxidative Stress; Resveratrol; Serine Endopeptidases; Signal Transduction; Stilbenes; Transcription Factor CHOP; Ubiquinone

Idebenone has been used as therapy for Friedreich ataxia for more than a decade. Although several studies have assessed the influence of therapy on neurologic or cardiac function, there is a paucity of data surrounding patient-reported outcome measures. In an observational study of the effect of intermediate-dose idebenone (20 mg/kg per day) on quality of life and neurologic function measures, seven patients with Friedreich ataxia were assessed using the Pediatric Quality of Life Inventory, the International Cooperative Ataxia Rating Scale, and an Activities of Daily Living Scale before initiation of idebenone therapy and after 1 year of therapy. Physical scores on the Pediatric Quality of Life Inventory were universally worse after 1 year, and correlated with decreased activities of daily living scores. Despite worsening physical scores, there was a trend toward improved total, emotional, social, and school components of quality of life scores after 1 year of idebenone therapy. There was no statistically significant change in Pediatric Quality of Life Inventory scores between baseline and 1 year of idebenone therapy. Functional ability, as measured by activities of daily living scores, appeared to have the most influence on the perception of physical quality of life, which may be important in planning future therapeutic trials.

Topics: Activities of Daily Living; Adolescent; Female; Follow-Up Studies; Friedreich Ataxia; Humans; Male; Prospective Studies; Quality of Life; Ubiquinone

Nanoparticles based on chitosan (Ch) and N-carboxymethylchitosan (N-CMCh) cross-linked with tripolyphosphate (TPP) were developed by co-drying with idebenone in different polymer-to-drug ratios (1.3:1 to 16:1) with 20% (wt/wt) colloidal silicon dioxide and tripolyphosphate (0.2 mg/mL). At high ratios (8:1 and 16:1) the spray-dried powder showed spherical and dense particles with a size close to 1 μm, allowing almost complete drug coating by the polymeric system and a high efficiency of drug incorporation (>90% and >80%, for Ch and N-CMCh, respectively). The nanoparticles showed a 10-fold increase of drug stability in comparison with free drug and preserved antioxidant activity in vitro. Compared with the severely irritative free form of idebenone, the nanoparticle formulation showed decreased mucous membrane irritation. These results revealed the potential of Ch and N-CMCh nanoparticles as carriers for a hydrophobic and irritative drug such as idebenone for topical or nasal use.

Topics: Antioxidants; Chitosan; Drug Carriers; Microscopy, Electron, Scanning; Nanoparticles; Particle Size; Spectrophotometry, Infrared; Ubiquinone

Evidence exists that nitric oxide (NO) may mediate both protective and pathological responses during brain hypoxia (HP). Reactive oxygen species have also been implicated in the pathophysiological response of the brain tissues to HP. Therefore, this study investigated whether a NO precursor, l-arginine (l-arg), a free radical scavenger, idebenone (ID), and their combination would reduce neurological injury resulting from hemic hypoxia (HP) in rats. Adult male Wistar albino rats were injected with sodium nitrite (60 mg/kg, s.c.) to establish hemic hypoxia. ID (100 mg kg(-1), i.p.) and/or l-arg (100 mg kg(-1), i.p.) were administrated 24 and 1h prior to sodium nitrite intoxication, respectively. Hypoxia significantly decreased hemoglobin concentration, while significantly increased serum lactate dehydrogenase (LDH), creatine phosphokinase (CPK), total nitrate/nitrite, sialic, and uric acids concentrations. Moreover, brain lipid peroxides were significantly enhanced, while reduced glutathione, l-ascorbic acids, adenosine triphosphate (ATP) contents, and the activities of catalase and superoxide dismutase, were significantly reduced in the brain tissue. Pretreatment with either ID or l-arg altered the majority of the above-mentioned biochemical changes in hypoxic rats. Additionally, the combination of these two agents significantly reduced injury marker enzyme activities as well as serum sialic, and uric acids level (P>0.05 vs. control). Moreover, this combination exerted a synergistic antioxidant effect by blocking the induction of lipid peroxidation, preserving brain energy (ATP) content, and greatly reducing the hypoxic alterations in brain enzymatic and non-enzymatic antioxidants. Histopathological examination of the brain tissue supported these biochemical findings. This study showed that ID and l-arg were capable of reducing neurological injury following HP in rat, and support the idea of the usefulness of l-arg and ID as prophylaxis from hypoxic brain injury.

Topics: Adenosine Triphosphate; Animals; Antioxidants; Arginine; Brain; Catalase; Creatine Kinase; Disease Models, Animal; Drug Administration Schedule; Drug Combinations; Gliosis; Hemoglobins; Hypoxia, Brain; L-Lactate Dehydrogenase; Male; Nervous System Diseases; Neurons; Nitrates; Nitric Oxide; Random Allocation; Rats; Rats, Wistar; Superoxide Dismutase; Time Factors; Ubiquinone

Coenzyme Q(10) (CoQ(10)) and its analogs are used therapeutically by virtue of their functions as electron carriers, antioxidant compounds, or both. However, published studies suggest that different ubiquinone analogs may produce divergent effects on oxidative phosphorylation and oxidative stress.. To test these concepts, we have evaluated the effects of CoQ(10), coenzyme Q(2) (CoQ(2)), idebenone, and vitamin C on bioenergetics and oxidative stress in human skin fibroblasts with primary CoQ(10) deficiency. A final concentration of 5 microM of each compound was chosen to approximate the plasma concentration of CoQ(10) of patients treated with oral ubiquinone. CoQ(10) supplementation for one week but not for 24 hours doubled ATP levels and ATP/ADP ratio in CoQ(10) deficient fibroblasts therein normalizing the bioenergetics status of the cells. Other compounds did not affect cellular bioenergetics. In COQ2 mutant fibroblasts, increased superoxide anion production and oxidative stress-induced cell death were normalized by all supplements.. THESE RESULTS INDICATE THAT: 1) pharmacokinetics of CoQ(10) in reaching the mitochondrial respiratory chain is delayed; 2) short-tail ubiquinone analogs cannot replace CoQ(10) in the mitochondrial respiratory chain under conditions of CoQ(10) deficiency; and 3) oxidative stress and cell death can be counteracted by administration of lipophilic or hydrophilic antioxidants. The results of our in vitro experiments suggest that primary CoQ(10) deficiencies should be treated with CoQ(10) supplementation but not with short-tail ubiquinone analogs, such as idebenone or CoQ(2). Complementary administration of antioxidants with high bioavailability should be considered if oxidative stress is present.

Topics: Adenosine Diphosphate; Adenosine Triphosphate; Ascorbic Acid; Cells, Cultured; Fibroblasts; Humans; Molecular Structure; Superoxides; Ubiquinone

Analogues of mitoQ and idebenone were synthesized to define the structural elements that support oxygen consumption in the mitochondrial respiratory chain. Eight analogues were prepared and fully characterized, then evaluated for their ability to support oxygen consumption in the mitochondrial respiratory chain. While oxygen consumption was strongly inhibited by mitoQ analogues 2-4 in a chain length-dependent manner, modification of idebenone by replacement of the quinone methoxy groups by methyl groups (analogues 6-8) reduced, but did not eliminate, oxygen consumption. Idebenone analogues 6-8 also displayed significant cytoprotective properties toward cultured mammalian cells in which glutathione had been depleted by treatment with diethyl maleate.

Topics: Antioxidants; Cytoprotection; Glutathione; Humans; Mitochondria; Organophosphorus Compounds; Oxygen Consumption; Ubiquinone

Topics: Adult; Antioxidants; Chronic Disease; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Migraine Disorders; Treatment Outcome; Ubiquinone

Duchenne muscular dystrophy (DMD) is a severe and still incurable disease, with heart failure as a leading cause of death. The identification of a disease-modifying therapy may require early-initiated and long-term administration, but such type of therapeutic trial is not evident in humans. We have performed such a trial of SNT-MC17/idebenone in the mdx mouse model of DMD, based on the drug's potential to improve mitochondrial respiratory chain function and reduce oxidative stress.. In this study, 200 mg/kg bodyweight of either SNT-MC17/idebenone or placebo was given from age 4 weeks until 10 months in mdx and wild-type mice. All evaluators were blinded to mouse type and treatment groups. Idebenone treatment significantly corrected cardiac diastolic dysfunction and prevented mortality from cardiac pump failure induced by dobutamine stress testing in vivo, significantly reduced cardiac inflammation and fibrosis, and significantly improved voluntary running performance in mdx mice.. We have identified a novel potential therapeutic strategy for human DMD, as SNT-MC17/idebenone was cardioprotective and improved exercise performance in the dystrophin-deficient mdx mouse. Our data also illustrate that the mdx mouse provides unique opportunities for long-term controlled prehuman therapeutic studies.

Topics: Animals; Antioxidants; Biomarkers; Cardiotonic Agents; Diastole; Dobutamine; Echocardiography; Fibrosis; Male; Mice; Mice, Inbred mdx; Mitochondrial Diseases; Muscle, Skeletal; Muscular Dystrophy, Animal; Myocardium; Oxidative Stress; Physical Conditioning, Animal; Placebos; Single-Blind Method; Time Factors; Troponin I; Ubiquinone

Respiratory failure can be the direct cause of death in patients with Leigh syndrome. Unfortunately, no effective treatment strategy is available. Here, we report successful treatment of a patient with Leigh syndrome using idebenone, a derivative of coenzyme Q-10. The patient's brainstem function, especially respiratory function, improved after idebenone treatment. Idebenone may be worth trying in patients with Leigh syndrome.

Topics: Adolescent; Brain Stem; Evoked Potentials, Auditory, Brain Stem; Follow-Up Studies; Humans; Lactic Acid; Leigh Disease; Male; Polysomnography; Respiration; Respiratory Insufficiency; Ubiquinone

The aim of this study was to investigate inherent in vitro permeability, metabolism, and cytotoxicity of idebenone - an active used to protect skin as an anti-aging agent - and compare it to idebenone linoleate.. Idebenone and idebenone linoleate were investigated in pig ear skin and melanoma (B16: F10 mouse) cells. Diffusion experiments were conducted at 37 degrees C (bath temperature) using Franz diffusion cells. Authentic metabolite samples were synthetically prepared. Samples were analyzed using liquid chromatography-mass spectrometry/mass spectrometry. Cell viability was determined via the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay.. Idebenone was shown to permeate across viable porcine ear tissue; there was no evidence that idebenone linoleate permeated across porcine ear tissue after 4 h. Idebenone was metabolized to idebenone acid in both pig ear and mouse melanocytes; only minor idebenone linoleate metabolism was observed. Idebenone displayed delayed in vitro toxicity (via MTT assay) in melanocytes, while idebenone linoleate displayed no such in vitro toxicity.. The in vitro metabolism and cytotoxicity results suggest that metabolic activation of idebenone is the likely culprit that activates the skin irritation mechanism via idebenone in vivo usage. An idebenone ester (e.g. idebenone linoleate) appears to provide a superior in vitro safety profile over idebenone.

Topics: Animals; Cells, Cultured; Chromatography, High Pressure Liquid; Ear, External; Immunohistochemistry; In Vitro Techniques; Linoleic Acid; Mass Spectrometry; Melanocytes; Mice; Sensitivity and Specificity; Skin Absorption; Ubiquinone

Topics: Antioxidants; Friedreich Ataxia; Humans; Ubiquinone

Left ventricular hypertrophy (LVH) is a frequent finding in Friedreich's ataxia (FRDA). In previous studies treatment with idebenone, a synthetic analogue of coenzyme Q10, has been associated with a substantial decrease in myocardial hypertrophy, despite great variability in cardiac responsiveness among patients. Here we present the results of a retrospective analysis of a cohort of 35 patients (20 with LVH, 15 without LVH) with confirmed molecular diagnosis of FRDA, treated with idebenone 5 mg/kg/day for up to five years. At the end of the study, we found an increase of interventricular septum and posterior wall thickness in the group without LVH before treatment and no change in the group with LVH before treatment. The neurological picture of the disease significantly deteriorated with time in both groups.

Topics: Adult; Analysis of Variance; Antioxidants; Cohort Studies; Echocardiography; Female; Follow-Up Studies; Friedreich Ataxia; Heart; Heart Septum; Humans; Hypertrophy, Left Ventricular; Male; Myocardium; Retrospective Studies; Severity of Illness Index; Ubiquinone

Noben (idebenone) at a dose of 120 mg per day for six months was used in the treatment of 35 patients aged 60-86 years with Alzheimer's-type dementia, mixed dementia, and memory impairments not reaching the stage of dementia. Patients were assessed on the basis of data from somatic, neurological, and psychiatric investigations, as well as neuropsychological testing and a series of psychometric and other scales and tests, before and after treatment. Significant improvements in patients' conditions on the MMSE were seen in patients with mild and moderate dementia. Improvements in daily activities were obtained in 27% of patients. Neuropsychological investigations demonstrated improvements in short-term and long-term memory and attention, with improvements in speech functions, performance of kinesthetic, spatial, and dynamic praxis tests, and in visuospatial gnosis, thought, and writing. On the CGI scale, positive treatment effects were obtained in 37% of patients, while 48% of patients remained in a stable state.

Topics: Aged; Aged, 80 and over; Antioxidants; Attention; Cognition; Cognition Disorders; Dementia; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Humans; Male; Memory; Middle Aged; Neuropsychological Tests; Severity of Illness Index; Time Factors; Treatment Outcome; Ubiquinone

In children with Friedreich's ataxia (FRDA children), clinical ataxia outcomes are hardly substantiated by underlying neurophysiological parameters. In young FRDA children, some reports (based upon International Cooperative Ataxia Rating Scale scores (ICARS)) mention transient neurological improvement upon idebenone treatment. However, these outcomes are obtained with adult instead of pediatric reference values. It is unknown whether age-related neurophysiological parameters can really substantiate neurologic improvement.. In young FRDA children, we aimed to determine longitudinal neurophysiological parameters during idebenone treatment.. During a two-year study period, 6 genetically proven FRDA children with cardiomyopathy (6-18years) were longitudinally assessed for neurophysiological parameters [sensory evoked potentials (SEPs), F response, peripheral nerve conduction and dynamometry] in association with age-matched ICARS-scores.. In all FRDA children, SEPs remained absent during the two-year study period. Peroneal nerve conduction velocity declined (from -1SD to -2SD; p<.05), whereas F responses remained essentially unaltered. Total muscle force and leg muscle force decreased (from -2 to -3SD and -2.5 to -3.5SD; both p<.05) and age-related ICARS-scores deteriorated (median increase +41%; p<.05).. In FRDA children, age-related neurophysiological and ataxia parameters deteriorate during idebenone treatment. Although we cannot exclude some (subjective) disease stabilization, age-related neurophysiological parameters do not substantiate neurologic improvement.

Topics: Adolescent; Age Factors; Antioxidants; Child; Evoked Potentials, Somatosensory; Friedreich Ataxia; Humans; Longitudinal Studies; Muscle Strength Dynamometer; Neural Conduction; Treatment Outcome; Ubiquinone

Topics: Administration, Cutaneous; Adult; Antioxidants; Cosmetics; Dermatitis, Allergic Contact; Facial Dermatoses; Female; Humans; Patch Tests; Skin Aging; Ubiquinone

Effect of CoQ compounds (Qs) on reactive oxygen (ROS) generation by mitochondrial complex I was studied using rat liver mitochondria and chemiluminescence probe L012. Kinetic analysis revealed that short chain Qs, such as Q2 and idebenone enhanced ROS generation by mitochondrial NADH oxidase system by a succinate-inhibitable mechanism. Lipid peroxidation in mitochondrial membranes induced by NADH and iron was inhibited by short chain Qs. The inhibitory activity was enhanced by co-oxidation of succinate as determined by chemiluminescence method and by electron spin resonance spectroscopy. These results suggested that the reduced form of short chain Qs inhibited mitochondrial ROS generation and lipid peroxidation.

Topics: Animals; Male; Metabolic Networks and Pathways; Mitochondria, Liver; Oxidoreductases; Rats; Rats, Wistar; Reactive Oxygen Species; Ubiquinone

The aim of this work was to study the effect of the drug idebenone on the growth of a strain of Saccharomyces cerevisiae yeast and its respiratory-deficient mutant (rho(0)). We took this yeast as a model system of the interaction of the drug with mammalian cells. The effect of idebenone was evaluated in rich and minimal media. In the S288c strain, idebenone exerted a growth inhibitory effect in concentrations higher than 50 microM in media containing a carbon source consumed at mitochondrial level. In conditions of low oxygen supply, idebenone allows yeast to keep a cellular yielding comparable with conditions of normal oxygen supply. Also, the presence of idebenone in the growth media increased by 50% the fluorescence signal of rhodamine 123, indicating a higher mitochondrial membrane potential. The results could explain the effect of idebenone in the treatment of diseases in which oxygen deficiency alters the energetic metabolism of the cell.

Topics: Culture Media; Mitochondria; Oxygen; Rhodamine 123; Saccharomyces cerevisiae; Ubiquinone

Antioxidant therapy is a new therapeutical approach for patients with Friedreich ataxia.. To assess the effectiveness of long-term idebenone treatment in Friedreich ataxia patients.. An open-labelled prospective study. Ten paediatric patients (age range 8-18 years) and 14 adults (age range 18-46 years) with genetic diagnosis of Friedreich ataxia were treated with idebenone (5-20mg/kg/day) for 3-5 years. Neurological evolution was evaluated using the International Cooperative Ataxia Rating Scale (ICARS), and cardiological outcomes using echocardiography.. In paediatric patients, no significant differences were observed in ICARS scores and echocardiographic measurements when comparing baseline status and after 5 years of follow-up. Concerning adult cases, ICARS scores showed a significant increase in neurological dysfunctions during 3 years of therapy (Wilcoxon test, p=0.005), while echocardiographic measurements remained unchanged.. Our results indicate that longer-term idebenone treatment prevented progression of cardiomyopathy in both paediatric and adult patients, whereas its stabilizing effect on neurological dysfunction was present only in the paediatric population, mainly before puberty. This suggests that the age at which idebenone treatment is initiated may be an important factor in the effectiveness of the therapy.

Topics: Adolescent; Adult; Antioxidants; Child; Echocardiography; Female; Follow-Up Studies; Friedreich Ataxia; Heart Diseases; Heart Function Tests; Humans; Male; Neurologic Examination; Neuropsychological Tests; Treatment Outcome; Ubiquinone; Young Adult

Idebenone, a synthetic analogue of coenzyme Q, attenuates noise-induced hearing loss by virtue of its antioxidant properties. This study involves a guinea pig model of acoustic trauma where the effectiveness of idebenone is analyzed in comparison with Vitamin E (alpha-tocopherol) that exhibits a potent antioxidant activity in the inner ear. Idebenone and vitamin E were injected intraperitoneally 1 h before noise exposure and once daily for three days; functional and morphological studies were then carried out, respectively, by auditory brainstem responses evaluation, scanning electron microscopy and terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay identification of missing and apoptotic cells was also performed. The results showed that the protective effects of idebenone and vitamin E were not additive implying that the two antioxidants may share competitive mechanisms.

Topics: Animals; Antioxidants; Benzoquinones; Drug Synergism; Electrophysiology; Guinea Pigs; Hearing; Hearing Loss, Noise-Induced; In Situ Nick-End Labeling; Microscopy, Electron, Scanning; Noise; Organ of Corti; Ubiquinone; Vitamin E

Diarrhea and anemia are side effects of mycophenolic acid (MPA), but underlying mechanisms are not fully understood. Gene expression of major-alpha-hemoglobin and catalase was suppressed in livers of mycophenolate mofetil (MMF)-treated rats, suggesting MPA attenuates cellular defense against reactive oxygen species (ROS). We investigated whether the antioxidant idebenone might alleviate MPA-related side effects.. Rats were treated as follows: group 1: controls; group 2: idebenone; group 3: MMF; and group 4: MMF/idebenone. Blood was collected weekly to determine cell counts, hemoglobin, MPA, plasma albumin, total protein, creatinine, and urea concentrations. On day 28 RNA was extracted from liver, kidneys, and bone marrow (BM). Colon and jejunum were examined histologically.. High-dose MMF-treated rats developed diarrhea, dehydration, and weight loss. After a week, a significant decrease (P=0.001) in erythrocyte count and hemoglobin concentration was observed that was not influenced by idebenone. Degenerative changes in the jejunum were slightly attenuated by idebenone. Idebenone did not influence MPA-induced suppression of catalase. A significant suppression of major-alpha-hemoglobin and the erythropoietin (EPO)-receptor in BM of MMF-treated groups and almost complete absence of hemopoietic progenitor cells were observed. EPO-mRNA was markedly upregulated in the MMF-group and even more in the MMF/idebenone-group.. Idebenone showed minimal benefit on MMF-related diarrhea and anemia. BM of MMF-treated rats revealed erythroid aplasia as a possible reason for anemia. Marked upregulation of EPO-mRNA presumably reflects a compensatory mechanism. Because ROS have the potential to suppress EPO expression, it can be hypothesized that enhanced EPO-mRNA expression in MMF/idebenone-treated rats is caused by antagonism of ROS.

Topics: Animals; Antioxidants; Catalase; Colon; DNA, Complementary; Erythropoietin; Female; Gene Expression Regulation; Hemoglobins; Immunosuppressive Agents; Jejunum; Models, Animal; Mycophenolic Acid; Rats; Rats, Wistar; Receptors, Erythropoietin; Reverse Transcriptase Polymerase Chain Reaction; Ubiquinone

Topics: Administration, Cutaneous; Adult; Antioxidants; Benzoquinones; Cosmetics; Dermatitis, Allergic Contact; Dermatologic Agents; Female; Humans; Patch Tests; Skin Aging; Ubiquinone

Topics: Administration, Cutaneous; Antioxidants; Benzoquinones; Cosmetics; Dermatitis, Allergic Contact; Dermatologic Agents; Female; Humans; Middle Aged; Patch Tests; Skin Aging; Ubiquinone

Idebenone (IDE), a synthetic analog of coenzyme Q, strongly activates glycerol phosphate (GP) oxidation in brown adipose tissue mitochondria. GP oxidase, GP cytochrome c oxidoreductase and GP dehydrogenase activities were all significantly stimulated by 13 muM IDE. Substituted derivatives of IDE acetyl- and methoxyidebenone had similar activating effects. When succinate was used as substrate, no activation by IDE could be observed. The activation effect of IDE could be explained as release of the inhibition of glycerol phosphate dehydrogenase by endogenous free fatty acids. NADH oxidoreductase activity and oxidation of NADH-dependent substrates were inhibited by IDE. The extent of the inhibition and IDE concentration dependence varied when various substrates were tested, being highest for pyruvate and lowest for 2-oxoglutarate. This study thus showed that the effect of IDE on various mitochondrial enzymes is very different and thus its therapeutic use should take into account its specific effect on various mitochondrial dehydrogenases in relation to particular defects of mitochondrial respiratory chain.

Topics: Adipose Tissue, Brown; Animals; Cells, Cultured; Cricetinae; Dose-Response Relationship, Drug; Electron Transport; Enzyme Activation; Male; Mitochondria; Ubiquinone

The goal of this study was to determine the ability of two putative antioxidant solutions to suppress the formation of superoxide anion radicals created by optical excitation of a photosensitizer and measured by highly sensitive luminometric detection.. Solutions containing 3% antioxidant complex and 1% idebenone were tested. The antioxidant complex is an aqueous combination of botanical extracts rich in ferulic acid, caffeic acid, and other polyphenols. Idebenone is a lower molecular weight analog of coenzyme Q(10) (a potent antioxidant). Each was dissolved in lipid soluble reagents (solutions) and run through a Photochem (photochemiluminometer system) device. Their antioxidant capacity was expressed as nmol equivalents of synthetic vitamin E. Nine aliquots of each compound were measured. The mean antioxidant capacities for the 3% antioxidant complex and 1% idebenone were 525 +/- 23 and 213 +/- 14 nmol, respectively, with a statistically significant difference between the two compounds (P < 0.001).. The 3% antioxidant solution possesses a significant antioxidative capacity, which was 2.5 times greater than the known antioxidant idebenone in a 1% solution as shown by the quenching of superoxide anion radicals measured by photochemiluminescence. This method provides rapid, accurate, and sensitive measurement of the antioxidant properties of lipid-soluble compounds.

Topics: Antioxidants; Caffeic Acids; Coumaric Acids; Flavonoids; Luminescence; Luminescent Measurements; Phenols; Plant Extracts; Polyphenols; Solubility; Superoxides; Ubiquinone; Ultraviolet Rays; Vitamin E

Topics: Administration, Cutaneous; Allergens; Antioxidants; Benzoquinones; Dermatitis, Allergic Contact; Diagnosis, Differential; Facial Dermatoses; Female; Humans; Middle Aged; Patch Tests; Skin Aging; Ubiquinone

Friedreich Ataxia (FRDA), the most frequent inherited ataxia, is not only characterized by progressive gait and limb ataxia, but in most cases is also accompanied by a severe hypertrophic cardiomyopathy. This life threatening symptom can be ameliorated by the administration of idebenone, a short chain quinone antioxidant, supporting additional evidence that oxidative stress plays a major role in the pathogenesis of this disease. In this study we analyze the combinatorial effect of different antioxidants on cell viability of FRDA fibroblasts and of RAT-1 immortalized fibroblasts exposed to oxidative stress. We find that an equimolar mixture of idebenone and vitamin E is more potent than each of the compound alone. Increased potency was also obtained with a novel synthetic antioxidant (Fe-Aox29) combining the active groups from both idebenone and vitamin E. These results indicate, that idebenone and vitamin E might act synergistically to counteract oxidative stress in fibroblasts from FRDA patients.

Topics: Animals; Antioxidants; Benzoquinones; Cell Line, Transformed; Cell Survival; Chromans; Fibroblasts; Friedreich Ataxia; Humans; Hydrogen Peroxide; Protective Agents; Rats; Reactive Oxygen Species; Ubiquinone; Vitamin E

To ascertain the efficacy of idebenone and multivitamin treatment in Leber's hereditary optic neuropathy (LHON).. Two patients diagnosed of unilateral LHON were treated with megadoses of idebenone, vitamin C and riboflavin for one year. They were examined clinically before, during and after treatment.. No improvement of visual function was observed. Despite the idebenone treatment, in both cases the second eye became involved.. Despite previous reports of visual recovery with idebenone in patients with LHON, our experience shows that an effective treatment for Leber's disease remains to be found.

Topics: Adult; Antioxidants; Ascorbic Acid; Benzoquinones; Female; Humans; Male; Optic Atrophy, Hereditary, Leber; Riboflavin; Treatment Failure; Ubiquinone; Vitamin B Complex; Vitamins

L-ergothioneine (EGT) is a stable antioxidant found in food plants as well as in animal tissue undergoing relatively high levels of oxidative stress. Idebenone is a stable analog of the antioxidant coenzyme Q(10). All are potent antioxidants found in skincare products, but their relative potencies are not well described.. To establish the physiological relevance of EGT by examining transcription of the EGT transporter gene OCTN-1 and production of the receptor protein in skin fibroblasts. In addition, to compare the inhibition of lipid peroxide formation by coenzyme Q(10) and EGT. Furthermore, to compare the peroxide-scavenging abilities of EGT and idebenone in both simple solution and in cell cultures exposed to ultraviolet A (UVA).. OCTN-1 expression and production in cultured fibroblasts were measured through real-time reverse transcription-PCR and Western blotting, respectively. Alloxan-induced lipid peroxidation in liposomes was used to evaluate the inhibition of lipid peroxide formation. The abilities of EGT and idebenone to directly scavenge hydroxyl radicals produced by H(2)O(2 )were determined. Finally, we irradiated fibroblasts with UVA340 radiation and compared antioxidant capabilities to scavenge free radicals.. We found that OCTN-1 is expressed and readily detectable in cultured human fibroblasts. EGT was more efficient in inhibiting lipid peroxide formation than coenzyme Q(10) or idebenone. Samples treated with EGT had significantly less peroxide than those treated with idebenone 120 min after adding the antioxidants to H(2)O(2). EGT acted significantly quicker and more efficiently in capturing reactive oxygen species (ROS) after UVA340 irradiation.. EGT is a natural skin antioxidant, as evidenced by the presence of the EGT transporter in fibroblasts. EGT is a more powerful antioxidant than either coenzyme Q(10) or idebenone due to its relatively greater efficiency in directly scavenging free radicals and in protecting cells from UV-induced ROS.

Topics: Alloxan; Analysis of Variance; Antioxidants; Benzoquinones; Cells, Cultured; Ergothioneine; Fibroblasts; Humans; Lipid Peroxidation; Liposomes; Organic Cation Transport Proteins; Peroxides; Polymerase Chain Reaction; Reactive Oxygen Species; RNA, Messenger; Symporters; Ubiquinone; Ultraviolet Rays

The results of treatment with noben (idebenon), an improved structural analogue of coenzyme Q10, of 34 patients with Friedrich's disease are presented. In all cases, the clinical diagnosis was confirmed by the presence of a typical mutation, an expansion of trinucleotide GAA-repeats, in the FRDA gene. All patients received noben as a main drug in dosage 5 mg/kg daily during 3 months. An examination of the patients included modern laboratory and instrumental methods, analysis of levels of lactic and pyruvic acids and their ratio in the peripheral blood. Also parameters of lipid peroxidation and mitochondrial dehydrogenase activity in peripheral lymphocytes were studied. Positive changes were found in the majority of patients for muscle strength in extremities, tolerability to physical loadings, general fatigue, movement activity, speech and coordination functions, along with significant improvement of biochemical and cytochemical status. The results obtained suggest a positive effect of noben on cell energy metabolism in this severe disorder from the group of mitochondrial cytopathies.

Topics: Adolescent; Adult; Antioxidants; Child; DNA Mutational Analysis; DNA, Mitochondrial; Dose-Response Relationship, Drug; Energy Metabolism; Frataxin; Friedreich Ataxia; Humans; Iron-Binding Proteins; Lipid Peroxidation; Lymphocytes; Middle Aged; Mitochondria; Mutation; Oxidoreductases; Treatment Outcome; Ubiquinone

The established protective effect of coenzyme Q (CoQ) analogs is dependent on the location of reactive oxygen species (ROS) generation. One of these analogs--idebenone (hydroxydecyl-ubiquinone) is used as an antioxidative therapeutic drug. We tested its scavenging effect on the glycerophosphate (GP)-dependent ROS production as this enzyme was shown as a new site in the mitochondrial respiratory chain where ROS can be generated. We observed that idebenone inhibits both GP- and succinate-dependent ROS production. Idebenone and CoQ1 were found to be more efficient in the scavenging activity (IC50: 0.052 and 0.075 microM, respectively) than CoQ3 (IC50: 45.8 microM). Idebenone also inhibited ferricyanide (FeCN)-activated, GP-dependent ROS production. Our data thus extend previous findings on the scavenging effect of idebenone and show that it can also eliminate GP-dependent ROS generation.

Topics: Adipose Tissue, Brown; Animals; Antioxidants; Benzoquinones; Cricetinae; Ferricyanides; Free Radical Scavengers; Glycerophosphates; Hydrogen Peroxide; In Vitro Techniques; Male; Mesocricetus; Mitochondria; Oxygen Consumption; Reactive Oxygen Species; Succinates; Ubiquinone

Topics: Antioxidants; Ascorbic Acid; Benzoquinones; Coumaric Acids; Humans; Kinetin; Radiation-Protective Agents; Skin; Ubiquinone; Ultraviolet Rays; Vitamin E

Lipoamino acids (LAA) are useful promoieties to modify physicochemical properties of drugs, namely lipophilicity and amphiphilicity. The resulting membrane-like character of drug-LAA conjugates can increase the absorption profile of drugs through cell membranes and biological barriers. To show the role of amphiphilicity with respect to lipophilicity in the interaction of drugs with biomembranes, in the present study we evaluated the mode of such an interaction of lipophilic conjugates of LAA with the antioxidant drug idebenone (IDE). DSC analysis and transfer kinetic studies were carried out using dimyristoylphosphatidylcholine (DMPC) multilamellar liposomes (MLVs) as a model. For comparison, two esters of IDE with alkanoic acids were synthesized and included in the analysis. The experimental results indicate that based on their different structure, IDE-LAA conjugates interacted at different levels with respect to pure IDE with DMPC bilayers. In particular, a progressive penetration inside the vesicles was observed upon incubation of IDE-LAA compounds with empty liposomes. The enhanced amphiphilicity of the drug due to the LAA moieties caused more complex interactions with DMPC bilayers, compared to those registered with the native drug or IDE alkanoate esters.

Topics: Antioxidants; Benzoquinones; Butyric Acid; Calorimetry; Caproates; Membranes; Models, Biological; Models, Molecular; Prodrugs; Solubility; Spectrophotometry, Infrared; Ubiquinone

In this work we investigated the effects of oil phase lipophilicity on in vitro drug release from topical o/w microemulsions (MEs) containing low percentages of emulsifiers. Three different lipids, isopropyl myristate (IPM), isopropyl palmitate (IPP), and isopropyl stearate (IPS), whose lipophilicity increased in the order IPM < IPP

Topics: Algorithms; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Benzoquinones; Chemical Phenomena; Chemistry, Pharmaceutical; Chemistry, Physical; Chromatography, High Pressure Liquid; Data Interpretation, Statistical; Drug Stability; Emulsions; Membranes, Artificial; Molecular Weight; Naproxen; Oils; Pharmaceutical Preparations; Solvents; Spectrophotometry; Spectrophotometry, Ultraviolet; Sunscreening Agents; Surface-Active Agents; Ubiquinone

Growth of Helicobacter pylori was inhibited by the quinones, idebenone, duroquinone, menadione, juglone, and coenzyme Q(1) at low concentrations of 0.8 to 3.2 mug/ml. Idebenone specifically inhibited H. pylori growth by inhibiting respiration and decreasing the cellular ATP level. The respiratory inhibition was accompanied by reduction of idebenone by the H. pylori cells.

Topics: Adenosine Triphosphate; Animals; Antioxidants; Benzoquinones; Helicobacter pylori; Kinetics; Oxidation-Reduction; Ubiquinone

Idebenone is a synthetic analogue of coenzyme Q10 with antioxidant properties. The present study investigated the antioxidant activity of idebenone in the rescue of acoustic trauma. Noise-induced hearing loss was induced by exposing guinea pigs to a continuous pure tone and idebenone was injected intraperitoneally 1 h before noise exposure and once daily for 3 days. Guinea pigs treated with idebenone showed significantly smaller auditory threshold shifts than unprotected control animals. Missing and apoptotic cells were identified with scanning electron microscopy and terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay. Protected animals presented a lesser extent of both apoptotic activation and hair cell loss in the organ of Corti. Our results suggest an antioxidant function of idebenone in protection from noise-induced hearing loss and provide a rationale for exploring therapeutic strategies in humans.

Topics: Acoustic Stimulation; Analysis of Variance; Animals; Antioxidants; Apoptosis; Auditory Threshold; Benzoquinones; Dose-Response Relationship, Radiation; Guinea Pigs; Hearing Loss, Noise-Induced; In Situ Nick-End Labeling; Microscopy, Electron, Scanning; Time Factors; Ubiquinone

Topics: Antioxidants; Benzoquinones; Cardiotonic Agents; Clinical Trials as Topic; Friedreich Ataxia; Humans; Hypertrophy, Left Ventricular; Mitochondria, Heart; Oxidative Stress; Ubiquinone; Ultrasonography

Lipophilic conjugates of idebenone (IDE) with short-chain alkylamino acids were previously synthesized and evaluated in vitro for their antioxidant properties. In this study, their susceptibility to chemical and enzymatic hydrolysis was evaluated. Results indicated that these derivatives release the parent drug quantitatively via enzymatic hydrolysis by serum and liver esterases, with a cleavage rate related to the length of the alkyl side chain. Consequently, the present lipoamino acid conjugates of IDE are prodrugs and their in vivo effects are mediated through the parent compound released in the body.

Topics: Amino Acids; Animals; Benzoquinones; Cattle; Drug Evaluation, Preclinical; Drug Stability; Enzyme Stability; Lipid Metabolism; Lipids; Serum Albumin, Bovine; Ubiquinone

Friedreich ataxia (FRDA), a progressive neurodegenerative disorder associated with cardiomyopathy, is caused by severely reduced frataxin, a mitochondrial protein involved in Fe-S cluster assembly. We have recently generated mouse models that reproduce important progressive pathological and biochemical features of the human disease. Our frataxin-deficient mouse models initially demonstrate time-dependent intramitochondrial iron accumulation, which occurs after onset of the pathology and after inactivation of the Fe-S dependent enzymes. Here, we report a more detailed pathophysiological characterization of our mouse model with isolated cardiac disease by echocardiographic, biochemical and histological studies and its use for placebo-controlled therapeutic trial with Idebenone. The Fe-S enzyme deficiency occurs at 4 weeks of age, prior to cardiac dilatation and concomitant development of left ventricular hypertrophy, while the mitochondrial iron accumulation occurs at a terminal stage. From 7 weeks onward, Fe-S enzyme activities are strongly decreased and are associated with lower levels of oxidative stress markers, as a consequence of reduced respiratory chain activity. Furthermore, we demonstrate that the antioxidant Idebenone delays the cardiac disease onset, progression and death of frataxin deficient animals by 1 week, but does not correct the Fe-S enzyme deficiency. Our results support the view that frataxin is a necessary, albeit non-essential, component of the Fe-S cluster biogenesis, and indicate that Idebenone acts downstream of the primary Fe-S enzyme deficit. Furthermore, our results demonstrate that Idebenone is cardioprotective even in the context of a complete lack of frataxin, which further supports its utilization for the treatment of FRDA.

Topics: Animals; Benzoquinones; Cardiomyopathy, Dilated; Disease Models, Animal; Electrocardiography; Frataxin; Friedreich Ataxia; Iron-Binding Proteins; Iron-Sulfur Proteins; Mice; Mitochondria; Myocardium; Oxidative Stress; Ubiquinone

Quinone derivatives are among the rare compounds successfully used as therapeutic reagents to fight mitochondrial diseases. However, their beneficial effect appears to depend on their side chain which presumably governs their interaction with the respiratory chain. The effect of four quinone derivatives was comparatively studied on NADH- and succinate-competitive oxidation by a sub-mitochondrial fraction. Under our experimental conditions, the less hydrophobic derivatives (menadione, duroquinone) poorly affected electron flow from either NADH or succinate to oxygen, yet readily diverting electrons from isolated complex I. This latter effect was abolished by succinate addition. More hydrophobic derivatives (idebenone, decylubiquinone) stimulated oxygen uptake from succinate. But while NADH oxidation was slightly inhibited by idebenone, it was somewhat increased by decylubiquinone. As a result, idebenone strongly favoured succinate over NADH oxidation. This study therefore suggests that any therapeutic use of quinone analogues should take into account their specific effect on each respiratory chain dehydrogenase.

Topics: Animals; Benzoquinones; Binding, Competitive; Cell Respiration; Cells, Cultured; Dose-Response Relationship, Drug; Homeostasis; Mice; Mice, Inbred C57BL; Mitochondria, Liver; NAD; Oxidation-Reduction; Oxygen; Oxygen Consumption; Quinones; Substrate Specificity; Ubiquinone; Vitamin K 3

We studied plasma and cerebrospinal fluid (CSF) concentrations of idebenone in five Friedreich ataxia patients on treatment with this antioxidant, and plasma and CSF ubiquinone-10 (Q (10)) concentrations in 15 controls. CSF idebenone concentrations were below the detection limit in 3 Friedreich ataxia patients and no association could be demonstrated between plasma and CSF idebenone values. Q (10) CSF concentrations (median: 2.25 nmol/L) were approximately 300 times lower than those of plasma (median: 0.77 micro mol/L). No correlation was observed between plasma and CSF Q (10) concentrations. A significantly positive correlation was observed between CSF total protein values (range 8.1 - 107.5 mg/dL; median: 29.5) and CSF Q (10) concentrations (Spearman test: r = 0.664; p = 0.01). Our findings suggest that less idebenone is distributed to the brain than to other tissues, although CSF does not appear to be an appropriate material for treatment monitoring of idebenone and other quinoid compounds.

Topics: Adolescent; Adult; Antioxidants; Benzoquinones; Blood-Brain Barrier; Case-Control Studies; Child; Coenzymes; Friedreich Ataxia; Humans; Ubiquinone

The potential therapeutic advantages of the encapsulation of idebenone within pegylated liposomes were investigated in vitro on primary cortical astrocytes of rats. In particular, both the concentration-dependent effects and the therapeutic effectiveness toward excitotoxic injury, elicited by chronic treatment with ethanol (100 microM) for 12 days, were evaluated. The following parameters were taken into consideration to assay free or liposomally entrapped idebenone: lactic dehydrogenase release, respiratory capacity measured by tetrazolium salt conversion, glutamine synthetase, and the levels of constitutive and inducible 70-kDa heat shock proteins. To evaluate the effects on astrocytes, three different drug concentrations were used (0.5 microM, 5 microM, and 50 microM). At the highest concentration used (50 microM), a toxic effect of the free and liposomally entrapped drug was observed. Toxic effects seem to be due to a cellular membrane perturbation, as demonstrated by (45)Ca(2+) permeation. The therapeutic effect of free or liposomally entrapped idebenone on ethanol-induced injury of primary cortical astrocytes was evaluated as a function of the drug concentration. The drug liposome formulation was much more effective than the free drug in counteracting the ethanol-induced damage in astrocytes, i.e., 10-times-lower doses of liposomally entrapped idebenone are able to provide a greater protective action than the free drug. The improved action of idebenone-loaded liposomes is probably due to the greater drug bioavailability at the cellular level.

Topics: Animals; Astrocytes; Benzoquinones; Cells, Cultured; Cerebral Cortex; Drug Resistance; Ethanol; Liposomes; Neuroprotective Agents; Polyethylene Glycols; Rats; Rats, Wistar; Ubiquinone

The authors report 7 years of follow-up evaluation of a patient with coenzyme Q10 (CoQ10) deficiency. Initial symptoms of exercise intolerance and hyperlactatemia improved markedly with substitutive treatment. However, CoQ(10) supplementation did not prevent the onset of a cerebellar syndrome. A switch to idebenone treatment resulted in clinical and metabolic worsening, which disappeared with subsequent CoQ10 treatment. CoQ10 defects may cause progressive neurologic disease despite supplementation.

Topics: Benzoquinones; Carnitine; Cerebellar Ataxia; Cerebellum; Child, Preschool; Disease Progression; Drug Therapy, Combination; Exercise Tolerance; Female; Follow-Up Studies; Humans; Lactates; Magnetic Resonance Imaging; Mitochondria, Muscle; Mitochondrial Myopathies; Muscle, Skeletal; Treatment Failure; Ubiquinone; Vomiting

Topics: Benzoquinones; Double-Blind Method; Free Radical Scavengers; Friedreich Ataxia; Humans; Hypertrophy, Left Ventricular; Randomized Controlled Trials as Topic; Research Design; Ubiquinone

Severe hypertrophic cardiomyopathy in a 15 years old child with Friedreich ataxia was treated with idebenone on the basis of a preliminary study reported in the literature. After 3 months of treatment the muscle thickness and mass and idices of diastolic function on echocardiogram and ischaemic signs on ECG changed significantly.. Our data proves the preliminary results, so idebenobe treatment is very effective in the disease, where a deficiency of frataxin is involved in the regulation of mitochondral iron content which is responsible for myocardial injury. We suggest the widespread use of idebenone to treat patients with Friedreich ataxia and hypertrophic cardiomyopathy to improve the fatal prognosis of this type of cardiomyopathy.

Topics: Adolescent; Antioxidants; Benzoquinones; Cardiomyopathy, Hypertrophic; Child; Echocardiography; Electrocardiography; Female; Frataxin; Friedreich Ataxia; Humans; Iron-Binding Proteins; Mitochondria, Heart; Treatment Outcome; Ubiquinone

Friedreich Ataxia (FRDA), the most common inherited ataxia, arises from defective expression of the mitochondrial protein frataxin, which leads to increased mitochondrial oxidative damage. Therefore, antioxidants targeted to mitochondria should be particularly effective at slowing disease progression. To test this hypothesis, we compared the efficacy of mitochondria-targeted and untargeted antioxidants derived from coenzyme Q10 and from vitamin E at preventing cell death due to endogenous oxidative stress in cultured fibroblasts from FRDA patients in which glutathione synthesis was blocked. The mitochondria-targeted antioxidant MitoQ was several hundredfold more potent than the untargeted analog idebenone. The mitochondria-targeted antioxidant MitoVit E was 350-fold more potent than the water soluble analog Trolox. This is the first demonstration that mitochondria-targeted antioxidants prevent cell death that arises in response to endogenous oxidative damage. Targeted antioxidants may have therapeutic potential in FRDA and in other disorders involving mitochondrial oxidative damage.

Topics: Antioxidants; Benzoquinones; Cell Death; Drug Delivery Systems; Fibroblasts; Friedreich Ataxia; Humans; Mitochondria; Models, Biological; Organophosphorus Compounds; Oxidative Stress; Ubiquinone; Vitamin E

In this study, we investigated the involvement of reactive oxygen species (ROS) and calcium in staurosporine (STS)-induced apoptosis in cultured retinal neurons, under conditions of maintained membrane integrity. The antioxidants idebenone (IDB), glutathione-ethylester (GSH/EE), trolox, and Mn(III)tetrakis (4-benzoic acid) porphyrin chloride (MnTBAP) significantly reduced STS-induced caspase-3-like activity and intracellular ROS generation. Endogenous sources of ROS production were investigated by testing the effect of the following inhibitors: 7-nitroindazole (7-NI), a specific inhibitor of the neuronal isoform of nitric oxide synthase (nNOS); arachidonyl trifluoromethyl ketone (AACOCF(3)), a phospholipase A(2) (PLA(2)) inhibitor; allopurinol, a xanthine oxidase inhibitor; and the mitochondrial inhibitors rotenone and oligomycin. All these compounds decreased caspase-3-like activity and ROS generation, showing that both mitochondrial and cytosolic sources of ROS are implicated in this mechanism. STS induced a significant increase in intracellular calcium concentration ([Ca(2+)](i)), which was partially prevented in the presence of IDB and GSH/EE, indicating its dependence on ROS generation. These two antioxidants and the inhibitors allopurinol and 7-NI also reduced the number of TdT-mediated dUTP nick-end labeling-positive cells. Thus, endogenous ROS generation and the rise in intracellular calcium are important inter-players in STS-triggered apoptosis. Furthermore, the antioxidants may help to prolong retinal cell survival upon apoptotic cell death.

Topics: Adenine; Allopurinol; Animals; Antioxidants; Apoptosis; Arachidonic Acids; Benzoquinones; Blotting, Western; Calcium; Carbon; Caspase 3; Caspases; Cell Death; Cell Survival; Chick Embryo; Chromans; Coloring Agents; Cytosol; DNA Fragmentation; Enzyme Inhibitors; Glutathione; In Situ Nick-End Labeling; Indazoles; Metalloporphyrins; Mitochondria; Neurons; Nitric Oxide Synthase; Oligomycins; Protein Isoforms; Reactive Oxygen Species; Retina; Rotenone; Staurosporine; Tetrazolium Salts; Thiazoles; Time Factors; Ubiquinone; Uncoupling Agents; Xanthine Oxidase

Ethanol-induced neurological disorders have recently been characterised. Indeed, evidence has been collected indicating that chronic ethanol consumption leads to direct or indirect changes in the viability of central nervous system cells. Here we investigated the role of free radical overproduction in primary cortical rat astroglial cells undergoing chronic treatment with ethanol (100 microM). In particular, exposure of astroglial cell cultures to ethanol for 12 consecutive days produced an increased release of lactic dehydrogenase, a decrease on glutamine synthase activity being both effects accompanied by decrease in astroglial viability as detected by MTT (Thiazolyl Blue) test. These effects were accompanied by an increased formation of malondialdehyde (a marker of lipid peroxidation) and by abnormal formation of heat shock protein, being both effects antagonised by liposomally entrapped idebenone, a non-peptidyl free radical scavenger. Taken together, these results suggest that ethanol-induced injury on astroglial cells are mediated by abnormal formation of free radical species and this may represent a useful approach in the treatment of ethanol-related brain disorders.

Topics: Animals; Antioxidants; Astrocytes; Benzoquinones; Cells, Cultured; Central Nervous System Depressants; Cerebral Cortex; Ethanol; Free Radicals; Liposomes; Oxidative Stress; Rats; Rats, Wistar; Ubiquinone

Friedreich Ataxia (FRDA), the most prevalent of the inherited ataxias, is a multi-systemic disease with loss of sensory neurons and life-threatening hypertrophic cardiomyopathy as its most severe manifestations. Reduced levels of the mitochondrial protein frataxin lead to cell-damaging oxidative stress and consequently FRDA is considered as a model for more common neurodegenerative disorders in which reactive radicals and oxidative stress are involved. We have developed a cellular assay system that discriminates between fibroblasts from FRDA patients and unaffected donors on the basis of their sensitivity to pharmacological inhibition of de novo synthesis of glutathione. With this assay we observed that supplementation with selenium effectively improved the viability of FRDA fibroblasts, indicating that basal selenium concentrations are not sufficient to allow an adequate increase in the activity of certain detoxification enzymes (such as GPX). Furthermore, we characterized potential drug candidates and found that idebenone, a mitochondrially localized antioxidant that ameliorates cardiomyopathy in FRDA patients, as well as other lipophilic antioxidants protected FRDA cells from cell death. Our results also demonstrate for the first time that small-molecule GPX mimetics have potential as a novel treatment strategy for Friedreich Ataxia and presumably also for other neurodegenerative diseases with mitochondrial impairment.

Topics: Benzoquinones; Biological Assay; Biomimetics; Coenzymes; Fibroblasts; Friedreich Ataxia; Glutathione; Glutathione Peroxidase; Humans; In Vitro Techniques; Models, Biological; Ubiquinone

The protective antioxidant role of idebenone both as free drug and drug-loaded Tween 80-coated polyethyl-2-cyanoacrylate (PECA) nanocapsules is reported. The relationship between oxidative damage and apoptotic or nonapoptotic cell death is evaluated in vitro.. Idebenone-loaded nanocapsules were prepared with the interfacial polymerization method in the presence of Tween 80. Human nonimmortalized fibroblasts. under different stress conditions, either 0.5 mM diethylmaleate (DEM) for 60 min or 0.1 mM H2O2 for 30 min, were used as the experimental in vitro model. The production of reactive oxygen species, the cell viability, and the nuclear DNA damage were evaluated. The presence of apoptotic damage was evaluated both by the determination of caspase-3-like protein activity and by Promega's fluorescent apoptotic detection system.. DEM and H2O2 affected the cultured cells in different ways. DEM induced a moderate cellular insult, which was efficaciously antagonized by idebenone-loaded PECA nanocapsules. H2O2 elicited severe damage to nuclear DNA, which was reduced by idebenoneloaded PECA nanocapsules. The free drug was less effective than idebenone-loaded nanocapsules.. The findings reported here demonstrate that an improved antioxidant effect was obtained with a low idebenone concentration (0.5 microM) when the drug was entrapped within Tween 80-coated PECA nanocapsules.

Topics: Antioxidants; Apoptosis; Benzoquinones; Capsules; Caspase 3; Caspases; Cell Survival; Cyanoacrylates; DNA Damage; Fibroblasts; Free Radical Scavengers; Humans; Hydrogen Peroxide; L-Lactate Dehydrogenase; Maleates; Oxidative Stress; Ubiquinone

Idebenone is a quinone analog that is applied in the treatment of several neurological disorders including Friedreich ataxia and mitochondrial encephalomyopathies. Our aim was to develop an easy and sensitive analytical HPLC-procedure for the determination of idebenone in the serum of patients treated with this drug. Serum samples from nine paediatric patients diagnosed with Friedreich ataxia and receiving idebenone treatment were analyzed. Idebenone was separated from serum by reverse high-pressure liquid chromatography and analyzed using an electrochemical detection procedure. No interferences were observed during analysis of patient samples obtained prior to idebenone treatment. Calibration of idebenone concentration indicated a linear range between 500 pmol/l and 5 micromol/l and calculation of within-run and between-run coefficients of variation suggested adequate analytical quality for reliable determination. In agreement with previously reported data, during drug therapy, idebenone serum concentrations (basal conditions, range 0.1-0.49 micromol/l) were greatly elevated 90 min after an oral dose (range 0.66-3.63 micromol/l). Thus, we have developed a simple and rapid method that offers adequate analytical quality for accurate idebenone determination.

Topics: Adolescent; Antioxidants; Benzoquinones; Child; Chromatography, High Pressure Liquid; Electrochemistry; Female; Friedreich Ataxia; Humans; Male; Monitoring, Physiologic; Pharmacology, Clinical; Ubiquinone

Friedreich's ataxia (FRDA) is a neuro-degenerative disease causing limb and gait ataxia and hypertrophic cardiomyopathy. It results from a triplet expansion in the first intron of the frataxin gene encoding a mitochondrial protein of yet unknown function. Cells with low frataxin content display generalized deficiency of mitochondrial iron-sulfur cluster-containing proteins, which presumably denotes overproduction of superoxide radicals in these organelles. Idebenone, a short-chain quinone, may act as a potent free radical scavenger protecting mitochondria against oxidative stress. We therefore carried out an open trial of idebenone (oral supplementation; 5mg/kg/day) in a large series of FRDA patients and followed their left ventricular mass and function. Consistent and definitive worsening being observed in the natural course of the disease and cardiac hypertrophy having no chance of spontaneous reversal and to be subject to a placebo effect, the patient's heart status before and after the treatment was used to unambiguously establish the effect of the drug. After six months, heart ultrasound revealed more than 20% reduction of left ventricular mass in about half of the patients (p < 0.001) and no significant change in the other half. Since any measurable reversion of this pathogenic trait is highly significant, this demonstrates the efficiency of idebenone in controlling heart hypertrophy in FRDA. Owing to the absence of side effects of the drug, idebenone (up to 15mg/kg/day) should be prescribed for FRDA patients continuously as early as possible.

Topics: Administration, Oral; Adolescent; Adult; Antioxidants; Benzoquinones; Cardiomyopathy, Hypertrophic; Carrier Proteins; Child; Child, Preschool; Female; Frataxin; Friedreich Ataxia; Humans; Iron-Binding Proteins; Male; Treatment Outcome; Ubiquinone; Ventricular Function, Left

Idebenone, a synthetic analogue of coenzyme Q10, has been shown to improve cardiac function in patients with Friedreich ataxia and a deficiency of respiratory chain complexes I-III. We describe a woman with severe combined right and left heart failure due to a mitochondrial cardiomyopathy. The patient underwent an endomyocardial biopsy as part of an evaluation for cardiac transplantation. It showed severely decreased respiratory complex activities dependent on CoQ, pointing to CoQ depletion. Following idebenone treatment there was a dramatic improvement in her clinical status with resolution of the heart failure.

Topics: Adult; Antioxidants; Benzoquinones; Biopsy; Cardiomyopathies; Electron Transport Complex I; Electron Transport Complex II; Electron Transport Complex III; Female; Humans; Mitochondrial Myopathies; Multienzyme Complexes; NADH, NADPH Oxidoreductases; Oxidoreductases; Succinate Dehydrogenase; Ubiquinone

The previously unrecognised association of myoclonus in two patients with LHON with the 11778/ND4 pathogenic mutation is described. EEG failed to disclose epileptic figures, and a back averaging study suggested that myoclonus was cortical in origin in both patients.

Topics: Adult; Anti-Inflammatory Agents; Antioxidants; Benzoquinones; Biopsy; Disease Progression; Electroencephalography; Electromyography; Evoked Potentials, Visual; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Mutation; Myoclonus; Optic Atrophy, Hereditary, Leber; Steroids; Treatment Outcome; Ubiquinone; Visual Acuity

A new self-microemulsifying drug delivery system (SMEDDS) was developed to increase the dissolution rate, solubility, and, ultimately, bioavailability of a poorly water soluble drug, idebenone. Pseudoternary phase diagrams were used to evaluate the self-microemulsification existence area, and the release rate of idebenone was investigated. The mixtures consisting of Labrafac hydro or Labrafil 2609 (HLB values > 4) with the surfactant (Labrasol containing 80% Transcutol) and cosurfactant (Plurol oleique WL 1173) were found to be optimum formulations. Using the SMEDDS formulations of 5% to 20% of Labrafac hydro or Labrafil 2609 in combination with the surfactant/cosurfactant mixing ratio of 3, the microemulsion existence field was wider compared to the other SMEDDS formulations due to high affinity for the continuous phase. The in vitro dissolution rate of idebenone from SMEDDS was more than twofold faster compared with that of tablets. The developed SMEDDS formulation can be used as a possible alternative to traditional oral formulations of idebenone to improve its bioavailability.

Topics: Antioxidants; Benzoquinones; Biological Availability; Chemistry, Pharmaceutical; Drug Delivery Systems; Emulsions; Solubility; Surface-Active Agents; Ubiquinone

Expression of immediate early genes has been reported during reperfusion after ischemia in rat livers due to oxygen radical formation. This study investigates in perfused pig livers the effect of the antioxidant idebenone and of cold ischemia time on the gene expression of c-fos and c-jun.. Livers were perfused for 210 min after 0.5 h or 20 h ischemic storage (4 degrees C). One group of pigs was fed idebenone (280 mg/day/7days) prior to organ harvesting. C-fos and c-jun mRNA were determined by RT-PCR at 3, 30, 60, 120 180, 210 min during reperfusion.. Lipid peroxidation increased in liver tissue form 0.54 +/- 0.21 to 1. 09 +/- 0.54 nmol MDA/mg protein during reperfusion after 20 h compared to 0.5 h cold storage. This was antagonized by idebenone (0. 68 +/- 0.20 nmol/MDA/mg protein). C-fos and c-jun were strongly induced in livers stored for 20 h, which was attenuated by idebenone (p < 0.05).. These findings suggest that cold ischemia time and oxygen radicals are critical for immediate early gene expression and that application of an effective antioxidant can attenuate this early stress reaction of the pig liver.

Topics: Animals; Antioxidants; Benzoquinones; Cold Temperature; Disease Models, Animal; Female; Gene Expression Regulation; Genes, fos; Genes, jun; Humans; In Vitro Techniques; Lipid Peroxidation; Liver; Liver Transplantation; Male; Molecular Structure; Perfusion; Rats; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Time Factors; Ubiquinone

The authors investigated the effectiveness of idebenone combined with vitamin B2 and vitamin C in the treatment of patients with Leber hereditary optic neuropathy (LHON) in an early stage as compared with untreated patients with LHON. These agents may stimulate the formation of ATP.. For this retrospective study, the authors selected 28 outpatients with LHON from the Keio University Hospital. These patients were followed for 2 to 19 years from disease onset. They were divided into two groups: 14 untreated patients (11778 mutation in 10 patients, 3460 mutation in 2 patients, and 14484 mutation in 2 two patients); and 14 treated patients (11778 mutation in 11 patients, 3460 mutation in 1 patient, and 14484 mutation in 2 patients). The treated patients were administered medical treatment with idebenone, vitamin B2, and vitamin C for at least 1 year. The current study evaluated the following: 1) number of eyes with visual recovery > or = 0.3; 2) interval between the onset of LHON and the beginning of visual recovery; 3) interval between the onset of LHON and visual recovery to 0.3; and 4) interval between the beginning of medical treatment and the beginning of visual recovery in the treated subjects.. There was no significant difference in the number of eyes with visual recovery > or = 0.3 in the two groups with the 3460, 11778, or 14484 mutation. Patients with visual recovery showed a fenestrated scotoma or a clearing of central vision. The mean interval between the onset of LHON and the beginning of visual recovery was significantly shorter in the treated group (11.1 months) than in the untreated group (17.4 months) (P = 0.03). The mean interval between the onset of LHON and visual recovery to 0.3 was significantly shorter in the treated group (17.6 months) than in the untreated group (34.4 months) (P = 0.01). The mean interval between the initiation of medical treatment to the beginning of visual recovery was 5.4 months.. Results suggest that the administration of idebenone, vitamin B2, and vitamin C sped the recovery of vision in patients with LHON.

Topics: Adolescent; Adult; Age of Onset; Antioxidants; Ascorbic Acid; Benzoquinones; Drug Therapy, Combination; Female; Follow-Up Studies; Humans; Male; Middle Aged; Mutation; Optic Atrophies, Hereditary; Recovery of Function; Retrospective Studies; Riboflavin; Time Factors; Ubiquinone; Vision Disorders; Visual Acuity

In this study, we examined the effect of the neuroprotective agent 2, 3-dimethoxy-5-methyl-6-(10-hydroxydecyl)-1,4-benzoquinone (CV-2619) on reperfusion injury in cultured rat astrocytes after exposure to hydrogen peroxide (H(2)O(2))-containing medium. CV-2619 (10 nM to 10 microM) significantly attenuated the reperfusion-induced decrease in cell viability. The compound showed an anti-apoptotic effect in this astrocyte injury model. Antioxidants such as ascorbic acid, alpha-tocopherol and reduced glutathione also inhibited H(2)O(2) exposure-induced cytotoxicity. CV-2619 did not affect the levels of reactive oxygen species, but it increased nerve growth factor (NGF) production. The effect of CV-2619 on H(2)O(2) exposure-induced cytotoxicity was blocked by cycloheximide and anti-NGF antibody. The protective effect of CV-2619 was antagonized by the mitogen-activated protein (MAP)/extracellular signal-regulated kinase (ERK) kinase inhibitor 2'-amino-3'-methoxyflavone and the phosphatidylinositol-3 kinase inhibitor wortmannin. These findings suggest that the effect of CV-2619 is mediated at least partly by NGF production in astrocytes and that ERK and phosphatidylinositol-3 kinases play a role in the downstream mechanism.

Topics: Animals; Antioxidants; Astrocytes; Benzoquinones; Cells, Cultured; Nerve Growth Factor; Neuroprotective Agents; Rats; Rats, Wistar; Reperfusion Injury; Ubiquinone

To develop a sensitive method for the analysis of idebenone [Ide, 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-p-benzoquinone] in human plasma.. The concentrations in plasma were determined by a high performance liquid chromatography-mass spectrometry coupled with an atmosphere pressure chemical impact ion source method (LC/MS-APCI).. The chromatograms indicated a good separation of the analytes and there was no interference by other compounds. The coefficients of determination of the calibration curves were above 0.999. The calibration range was 20-600 micrograms.L-1. Peak plasma idebenone concentration (Cmax) of (316 +/- 85) micrograms.L-1 was achieved within (96 +/- 34) min (Tpeak) after an oral dose of 30 mg. Lower limit of quantitation of the method for Ide determination was 20 micrograms.L-1.. The advantages of using LC/MS-APCI technique include better sensitivity, higher selectivity, and less time consumption, compared with HPLC method.

Topics: Antioxidants; Benzoquinones; Chromatography, High Pressure Liquid; Humans; Mass Spectrometry; Ubiquinone

We report a patient with MELAS treated for 24 months with idebenone and riboflavin, during which no stroke-like episodes occurred. Moreover neurological symptoms clearly improved, and a recovery of brain MRI and EEG abnormalities was observed. We conclude that the combined treatment with idebenone and riboflavin may restore the metabolic impairment in MELAS, possibly improving the long-term prognosis in these patients.

Topics: Adult; Antioxidants; Aphasia, Wernicke; Benzoquinones; Cerebral Cortex; Cerebral Infarction; Drug Administration Schedule; Drug Therapy, Combination; Electron Transport; Humans; Magnetic Resonance Imaging; Male; MELAS Syndrome; Mitochondria; Photosensitizing Agents; Riboflavin; Treatment Outcome; Ubiquinone

The distribution patterns of amyloid precursor protein (APP) fragments were studied immunocytochemically in the rat brain before, after 10 min ischemia and following treatment by idebenone. Six months after brain ischemia intense staining for APP appeared in extra- and intracellular space. These findings indicate that APP is involved in the degeneration process of brain neuronal and glial cells following ischemia-reperfusion injury and anti-oxidative therapy did not prevent and/or stop this phenomenon.

Topics: Alzheimer Disease; Amyloid beta-Protein Precursor; Amyloidosis; Animals; Antioxidants; Benzoquinones; Cell Death; Drug Evaluation, Preclinical; Extracellular Space; Female; Free Radicals; Heart Arrest; Hypoxia-Ischemia, Brain; Intracellular Fluid; Neuroglia; Neurons; Neuroprotective Agents; Oxidative Stress; Rats; Rats, Wistar; Reperfusion Injury; Risk Factors; Ubiquinone

Amyloid beta-peptide (A beta), the major constituent of the senile plaques in the brains of patients with Alzheimer's disease, is cytotoxic to neurons and has a central role in the pathogenesis of the disease. Previous studies have suggested that oxidative stress is involved in the mechanisms of A beta-induced neurotoxicity in vitro. In the present study, we examined whether oxidative stress contributes to learning and memory deficits caused by continuous intracerebroventricular infusion of A beta-(1-42). In the A beta-(1-42)-infused rats, spontaneous alternation behaviour in a Y-maze and spatial memory in a water maze task were significantly impaired, as compared with A beta-(40-1)-infused control rats. The retention of passive avoidance learning was also significantly impaired by treatment with A beta-(1-42). Potent antioxidants idebenone and alpha-tocopherol prevented the behavioural deficits in Y-maze and water maze, but not passive avoidance, tasks in A beta-(1-42)-infused rats when they were repeatedly administered by mouth once a day from 3 days before the start of A beta infusion to the end of behavioural experiments. Lipid peroxide levels in the hippocampus and cerebral cortex of A beta-(1-42)-infused rats did not differ from those in control animals, and neither idebenone nor alpha-tocopherol affected the lipid peroxide levels. These results suggest that treatment with antioxidants such as idebenone and alpha-tocopherol prevents learning and memory deficits caused by A beta.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Antioxidants; Avoidance Learning; Benzoquinones; Brain Chemistry; Drug Interactions; Injections, Intraventricular; Lipid Peroxidation; Locomotion; Male; Maze Learning; Memory; Nerve Degeneration; Neurotoxins; Oxidative Stress; Peptide Fragments; Rats; Rats, Wistar; Ubiquinone; Vitamin E

We have studied the synthesis of [11C]2,3-dimethoxy-5-methyl-6-(10-hydroxy)-decyl-1,4-benzoquinone (idebenone) and [11C]2,3-dimethoxy-5-methyl-1,4-benzoquinone (CoQo) by methylation of their respective desmethyl precursors using [11C]CH3I for in vivo measurement of mitochondrial electron transfer and redox state. The [11C]idebenone was more lipophilic than [11C]CoQo; the latter became hydrophilic by reduction. Clearance of [11C]idebenone from mouse brain was more rapid than that of [11C]CoQo. The results indicated that modification of the isoprenoid side chain in [11C]CoQ is necessary to develop more suitable radiopharmaceuticals.

Topics: Animals; Benzoquinones; Brain; Carbon Radioisotopes; Electron Transport; Mice; Mitochondria; Molecular Structure; Oxidation-Reduction; Radiochemistry; Tissue Distribution; Ubiquinone

We studied the potential neuroprotective action of nicergoline in immortalized hypothalamic GT1-7 cells exposed to agents which deplete levels of reduced glutathione, thus causing oxidative stress and cell death. Treatment with diethylmaleate (1 mM), buthionine sulfoximine (500 microM) or menadione (10-50 microM) caused diffuse GT1-7 cell degeneration, as assessed by using either the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay or the fluorescent dyes fluorescein diacetate and propidium iodide. Pre- and/or co-exposure of the cells to nicergoline significantly prevented diethylmaleate- or buthionine sulfoximine-induced neuronal death, whereas nicergoline was ineffective against menadione-induced toxicity. This effect was concentration-dependent and was mimicked by the classical antioxidants idebenone and vitamin E, and did not depend on interference with protein kinase C. Interestingly, the antineurodegenerative activity of nicergoline and vitamin E or idebenone was not additive, suggesting that these compounds share some intracellular mechanism(s) responsible for their protective effects. In conclusion, the present data indicate that nicergoline has neuroprotective activity, possibly mediated by the antioxidant activity of the molecule, and give support to the potential use of nicergoline in the prevention and therapy of neurodegenerative diseases.

Topics: Animals; Antioxidants; Benzoquinones; Buthionine Sulfoximine; Cell Death; Cell Line; Cell Survival; Dose-Response Relationship, Drug; Enzyme Inhibitors; Maleates; Neurons; Neuroprotective Agents; Nicergoline; Staurosporine; Tetrazolium Salts; Thiazoles; Ubiquinone; Vitamin E

Idebenone, a compound with protective efficacy against neurotoxicity both in in vitro and in in vivo models, exists in two different oxidative states: the ubiquinol-derivative (reduced idebenone) and the ubiquinone-derivative (oxidised idebenone). In the present study, we have observed that both the redox forms of idebenone have a dose-dependent inhibitory effect on the enzymatic metabolism of arachidonic acid in astroglial homogenates (IC50 reduced idebenone: 1.76 +/- 0.86 microM; IC50 oxidised idebenone: 16.65 +/- 3.48 microM), while in platelets, they are apparently less effective (IC50 reduced idebenone: 18.28 +/- 4.70 microM; IC50 oxidised idebenone: > 1 mM). We have also observed that the oxidised form preferentially inhibited cyclooxygenase vs. lipoxygenase metabolism (IC50 ratio lipoxygenase/cyclooxygenase: 3.22), while the reduced form did not discriminate between the two pathways (IC50 ratio lipoxygenase/cyclooxygenase: 1.38). In this respect, the inhibitory action of reduced idebenone resembled that of the antioxidant nordihydroguaiaretic acid, while oxidised idebenone behaved similarly as indomethacin and piroxicam--two typical anti-inflammatory agents. Our results suggest the existence of two distinct mechanisms of action for the two redox forms of idebenone and a preferential action of the drug on arachidonic acid metabolism in the central nervous system.

Topics: Animals; Antioxidants; Arachidonic Acid; Astrocytes; Benzoquinones; Cells, Cultured; Chromatography, High Pressure Liquid; Hippocampus; Male; Neuroprotective Agents; Oxidation-Reduction; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Sprague-Dawley; Ubiquinone

A role for the antioxidants vitamin E and idebenone in decreasing retinal cell injury, after metabolic inhibition induced by chemical ischemia and hypoglycemia, was investigated and compared with oxidative stress conditions. Preincubation of the antioxidants, vitamin E (20 microM) and idebenone (10 microM), effectively protected from retinal cell injury after oxidative stress or hypoglycemia, whereas the protection afforded after postincubation of both antioxidants was decreased. Delayed retinal cell damage, mediated by chemical ischemia, was attenuated at 10 or 12 h postischemia, only after exposure to the antioxidants during all the experimental procedure. An antagonist of the N-methyl-D-aspartate (NMDA) receptors, an inhibitor of nitric oxide synthase (NOS) or a blocker of L-type Ca2+ channels were ineffective in reducing cell injury induced by chemical ischemia, hypoglycemia or oxidative stress. Oxidative stress and hypoglycemia increased (about 1.2-fold) significantly the fluorescence of the probe DCFH2-DA, that is indicative of intracellular ROS formation. Free radical generation detected with the probe dihydrorhodamine 123 (DHR 123) was enhanced after oxidative stress, chemical ischemia or hypoglycemia (about 2-fold). Nevertheless, the antioxidants vitamin E or idebenone were ineffective against intracellular ROS generation. Cellular energy charge decreased greatly after chemical ischemia, was moderately affected after hypoglycemia, but no significant changes were observed after oxidative stress. Preincubation with vitamin E prevented the changes in energy charge upon 6 h posthypoglycemia. We can conclude that irreversible changes occurring during chemical ischemia mainly reflect the alterations taking place at the ischemic core, whereas hypoglycemia situations may reflect changes occurring at the penumbra area, whereby vitamin E or idebenone may help to increase cell survival, exerting a beneficial neuroprotective effect.

Topics: Animals; Antioxidants; Benzoquinones; Calcium Channel Blockers; Cells, Cultured; Chick Embryo; Enzyme Inhibitors; Excitatory Amino Acid Antagonists; Free Radicals; Hypoglycemia; Ischemia; Neurons; Oxidative Stress; Reactive Oxygen Species; Retina; Ubiquinone; Vitamin E

Alzheimer's disease is widely held to be associated with oxidative stress due, in part, to the membrane action of amyloid beta-peptide (A beta) aggregates. In this study, the involvement of oxidative stress on A beta-induced energy metabolism dysfunction was evaluated on PC12 cells. It was shown that A beta peptides (A beta25-35 and A beta1-40) induce a concentration-dependent accumulation of reactive oxygen species (ROS), decrease the cellular redox activity, and lead to the depletion of ATP levels. The observed inhibition by A beta of mitochondrial function and of glycolysis is blocked by the antioxidants vitamin E, idebenone, and GSH ethyl ester. Taken together, these data suggest that exposure of PC12 cells to A beta results in an impairment of energy metabolism, leading to a deficit in ATP levels and to the compromise of cellular viability. Furthermore, the generation of ROS seems to be a crucial event responsible for the energetic metabolic dysfunction induced by A beta.

Topics: Adenosine Triphosphate; Amyloid beta-Peptides; Animals; Antioxidants; Benzoquinones; Deoxyglucose; Dose-Response Relationship, Drug; Electron Transport; Electron Transport Complex II; Electron Transport Complex III; Electron Transport Complex IV; Glutathione; Glycolysis; Mitochondria; Multienzyme Complexes; NAD(P)H Dehydrogenase (Quinone); Neurons; Neuroprotective Agents; Oxidative Stress; Oxidoreductases; PC12 Cells; Peptide Fragments; Pyruvic Acid; Rats; Succinate Dehydrogenase; Tritium; Ubiquinone; Vitamin E

Topics: Aconitate Hydratase; Benzoquinones; Coenzymes; Deferoxamine; Electron Transport Complex II; Friedreich Ataxia; Humans; Iron; Iron-Sulfur Proteins; Multienzyme Complexes; Oxidoreductases; Quinones; Succinate Dehydrogenase; Ubiquinone

Friedreich's ataxia is caused by a deficiency of frataxin, a protein involved in regulation of mitochondrial iron content. We have reported a combined deficiency of a Krebs-cycle enzyme, aconitase, and three mitochondrial respiratory-chain complexes in endomyocardial biopsy samples from patients with this disorder. All four enzymes share iron-sulphur cluster-containing proteins that are damaged by iron overload through generation of oxygen free radicals. We used an in-vitro system to elucidate the mechanism of iron-induced injury and to test the protective effects of various substances. On the basis of these results, we assessed the effect of idebenone (a free-radical scavenger) in three patients with Friedreich's ataxia.. Heart homogenates from patients with valvular stenosis were tested for respiratory-chain complex II activity, lipoperoxidation, and aconitase activity by spectrophotometric assays, in the presence of reduced iron (Fe2+), oxidised iron (Fe3+), desferrioxamine, ascorbic acid, and idebenone. The Friedreich's ataxia patients (aged 11 years, 19 years, and 21 years) underwent ultrasonographic heart measurements at baseline and after 4-9 months of idebenone (5 mg/kg daily).. Fe2+ (but not Fe3+) decreased complex II activity and increased lipoperoxidation in heart homogenate. Addition of ascorbate or desferrioxamine increased some of the iron-induced adverse effects. Idebenone protected against these effects. In the three patients, left-ventricular mass index decreased from baseline to 4-9 months of idebenone treatment (patient 1, 145 g to 114 g; patient 2, 215 g to 151 g; patient 3, 408 g to 279 g).. Our in-vitro data suggest that both iron chelators and antioxidant drugs that may reduce iron are potentially harmful in patients with Friedreich's ataxia. Conversely, our preliminary findings in patients suggest that idebenone protects heart muscle from iron-induced injury.

Topics: Adult; Antioxidants; Benzoquinones; Cardiac Volume; Cardiomyopathies; Child; Electron Transport Complex II; Female; Friedreich Ataxia; Humans; Iron Chelating Agents; Male; Multienzyme Complexes; Myocardium; Oxidoreductases; Succinate Dehydrogenase; Ubiquinone

Topics: Antioxidants; Benzoquinones; Female; Friedreich Ataxia; Glutathione Peroxidase; Glutathione Reductase; Humans; Selenium; Ubiquinone

Topics: Animals; Antioxidants; Benzoquinones; Cells, Cultured; Fermentation; Inhibitory Concentration 50; Lipid Peroxidation; Magnetic Resonance Spectroscopy; Microsomes, Liver; Molecular Structure; Neurons; Neuroprotective Agents; Piperazines; Rats; Spectrometry, Mass, Fast Atom Bombardment; Streptomyces; Ubiquinone

To observe the effects of four drugs, ligustrazine (Lig), tanshinone II A (Tan), ubiquinone (Ubi) and idebenone (Ide), on learning and memory of mouse.. Mouse water maze was used to evaluate nootropic effect.. In comparison with the defective model (only scopolamine 3 mg.kg-1, Tan 20 mg.kg-1, ig) shortened the escape latency dramatically from (36 +/- 19) s to (11 +/- 5) s (P < 0.01) and reduced errors from 7 +/- 5 to 1.5 +/- 1.3 (P < 0.05). Ubi 20 mg.kg-1 ig decreased the escape latency from (37 +/- 18) s to (17 +/- 12) s and errors from 8 +/- 5 to 2.1 +/- 2.7 (P < 0.01). Ide 120 mg.kg-1 (ig) reduced the errors from 8 +/- 6 to 3.4 +/- 2.9 (P < 0.05), but had no remarkable effect on the escape latency. Lig did not exhibit marked effect on the deficit.. Tan, Ubi, and Ide improved scopolamine-caused spatial performance defects in mouse.

Topics: Abietanes; Animals; Anticoagulants; Benzoquinones; Female; Fibrinolytic Agents; Male; Maze Learning; Mice; Phenanthrenes; Pyrazines; Ubiquinone

Idebenone [2,3-dimethoxy-5-methyl-6-(10-hydroxydecyl)-1,4-benzoquinone] is a synthetic analogue of coenzyme Q that is currently employed in the treatment of vascular and degenerative diseases of the central nervous system. There is some evidence to suggest that idebenone might function as an antioxidant; however, it has not been demonstrated whether this function pertains to the quinone or hydroquinone form of idebenone. Here we demonstrate that idebenone can scavenge a variety of free radical species, including organic radicals such as 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and diphenylpicrylhydrazyl, peroxyl and tyrosyl radicals, and peroxynitrite. Idebenone can also redox couple with hypervalent species of Mb or Hb, thus preventing lipid peroxidation promoted by these species. Likewise, idebenone inhibits microsomal lipid peroxidation induced by ADP-iron complexes or organic hydroperoxides. In so doing, idebenone prevents the destruction of cytochrome P450, which otherwise would accompany lipid peroxidation. Irrespective of the experimental system under investigation, idebenone functions by virtue of the electron-donating properties of the hydroquinone form. Redox coupling of this hydroquinone with free radicals generates the quinone compound, which per se lacks antioxidant activity. In many experiments, the antioxidant effects of idebenone become appreciable at approximately 2 microM, which is well in the range of plasma levels attainable in patients given oral doses of this drug. Moreover, comparative experiments have shown that the antioxidant efficiency of idebenone varies from no less than 50% to slightly more than 100% of that of vitamin E or Trolox. We would therefore propose that the neuroprotective effects of idebenone can be attributed, at least in part, to its ability to function as an antioxidant, involving redox cycling between hydroquinone and quinone.

Topics: Antioxidants; Arachidonic Acid; Benzoquinones; Free Radicals; Lipid Peroxidation; Peroxides; Ubiquinone

The effect of energetic metabolism compromise, obtained by chemical induction of hypoglycaemia (glucose deprivation), hypoxia (mitochondrial respiratory chain inhibition), and ischaemia (hypoglycaemia plus hypoxia), on glutamate toxicity was analyzed on PC12 cells. The respiratory status of these cells, measured by the MTT [3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide] assay, was significantly decreased after metabolic inhibition induced by ischaemia, but it was not affected by both hypoglycaemia and hypoxia. Under hypoglycaemia, but not under hypoxia, ATP levels were significantly reduced (from 12.67+/-0.48 to 5.38+/-1.41 nmol/mg protein). However, ischaemic-like conditions greatly potentiated the decline of ATP levels (95% decrease) observed after hypoglycaemia. The influence of metabolic inhibition on glutamate-induced cytotoxicity was also analyzed. When the cells were preincubated under conditions that deplete ATP (hypoglycaemia and ischaemia), the inhibition of MTT reduction, measured after glutamate incubation, was potentiated. This effect could be reverted when vitamin E and idebenone were present during the induction of metabolic inhibition. The ATP levels above which glutamate susceptibility was enhanced were also determined. These results indicate that glutamate toxicity on PC12 cells, which occurs by a mechanism independent of N-methyl-D-aspartate (NMDA) receptor activation, can be enhanced by the depletion of intracellular ATP upon metabolic stress; it is dependent on the extent of ATP depletion and seems to involve the generation of free radicals. It can be concluded that under ischaemic conditions, the deleterious effects of glutamate can be potentiated by the energetic compromise associated with this pathologic situation.

Topics: Adenosine Triphosphate; Animals; Antioxidants; Benzoquinones; Cell Hypoxia; Disease Susceptibility; Energy Metabolism; Glutamic Acid; Hypoglycemia; Ischemia; Mitochondria; PC12 Cells; Rats; Receptors, N-Methyl-D-Aspartate; Tetrazolium Salts; Thiazoles; Ubiquinone; Vitamin E

In the present study the effect of ascorbate (0.8 mM)/iron (2.5 microM) on lipid and protein oxidation, in Synaptosomes isolated from rat brain cortex, was evaluated. Vitamin E, idebenone and reduced glutathione were used as free radicals scavengers, in order to analyze the mechanism involved in ascorbate/iron-induced oxidative stress. An increased formation of reactive oxygen species (ROS) in the cytosol and in the mitochondria was observed, in ascorbate/iron treated synaptosomes. Idebenone (50 microM) prevented the increased formation of ROS in both synaptosomal compartments, vitamin E (150 microM) protected partially this formation in mitochondria, whereas reduced glutathione (250 microM) (GSH) was ineffective. After ascorbate/iron treatment an increase in lipid peroxidation occurred as compared to control, which was completely inhibited by idebenone. A decrease in protein-SH content was also observed, and it was prevented by Vitamin E, idebenone and GSH. When synaptosomes were treated with ascorbate/iron the levels of GSH decreased, and the levels of oxidized glutathione (GSSG) increased as compared to controls under these conditions. Glutathione peroxidase activity was unchanged, whereas an inhibition of glutathione reductase activity was observed. These data suggest that the increased formation of free radicals in synaptosomes leads to lipid and protein oxidation, the role of the endogenous GSH being essential to protect protein thiol-groups against oxidative damage in order to maintain enzyme activity.

Topics: Adenine Nucleotides; Animals; Antioxidants; Ascorbic Acid; Benzoquinones; Brain; Free Radical Scavengers; Free Radicals; Glutathione; Iron; Lipid Peroxidation; Male; Nerve Tissue Proteins; Oxidation-Reduction; Oxidative Stress; Rats; Rats, Wistar; Reactive Oxygen Species; Sulfhydryl Compounds; Synaptosomes; Ubiquinone; Vitamin E

Rats were given vitamin E (Vit-E), idebenone (ID), or vitamin C (Vit-C) in their food for 2 or 4 weeks. After feeding, the ability of rats to reduce 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol) in terms of the half-life of Tempol was examined as a specific marker. Tempol was repeatedly injected intravenously, and its half-life was serially evaluated by an in vivo electron spin resonance (ESR) technique. The radical-reducing ability in rats was enhanced differently by Vit-E, ID, and Vit-C, i.e., slow onset of the ability after Vit-E and ID (lipid-soluble antioxidants) and fast onset after Vit-C (a water-soluble antioxidant).

Topics: Animals; Antioxidants; Ascorbic Acid; Benzoquinones; Cyclic N-Oxides; Electron Spin Resonance Spectroscopy; Male; Oxidation-Reduction; Rats; Rats, Wistar; Spin Labels; Ubiquinone; Vitamin E

Oxidant stress induced by hydrophobic bile acids has been implicated in the pathogenesis of liver injury in cholestatic liver disorders. We evaluated the effect of idebenone, a coenzyme Q analogue, on taurochenodeoxycholic acid (TCDC)-induced cell injury and oxidant stress in isolated rat hepatocytes and on glycochenodeoxycholic acid (GCDC)-induced generation of hydroperoxides in fresh hepatic mitochondria. Isolated rat hepatocytes in suspension under 9% oxygen atmosphere were preincubated with 0, 50, and 100 micromol/l idebenone for 30 min and then exposed to 1000 micromol/l TCDC for 4 h. LDH release (cell injury) and thiobarbituric acid reactive substances (measure of lipid peroxidation) increased after TCDC exposure but were markedly suppressed by idebenone pretreatment. In a second set of experiments, the addition of 100 micromol/l idebenone up to 3 h after hepatocytes were exposed to 1000 micromol/l TCDC resulted in abrogation of subsequent cell injury and markedly reduced oxidant damage to hepatocytes. Chenodeoxycholic acid concentrations increased to 5.15 nmol/10(6) cells after 2 h and to 7.05 after 4 h of incubation of hepatocytes with 1000 micromol/l TCDC, and did not differ in the presence of idebenone. In freshly isolated rat hepatic mitochondria, when respiration was stimulated by succinate, 10 micromol/l idebenone abrogated the generation of hydroperoxides during a 90-minute exposure to 400 micromol/l GCDC. These data demonstrate that idebenone functions as a potent protective hepatocyte antioxidant during hydrophobic bile acid toxicity, perhaps by reducing generation of oxygen free radicals in mitochondria.

Topics: Animals; Antioxidants; Benzoquinones; Bile Acids and Salts; Chemical and Drug Induced Liver Injury; Glycochenodeoxycholic Acid; L-Lactate Dehydrogenase; Lipid Peroxidation; Liver; Male; Mitochondria, Liver; Oxidative Stress; Rats; Rats, Sprague-Dawley; Succinic Acid; Taurochenodeoxycholic Acid; Thiobarbituric Acid Reactive Substances; Ubiquinone

The application of amyloid beta-peptide (Abeta) 1-40 (10 microM) caused neurodegeneration of hippocampal neuronal cells, as indicated by the release of lactate dehydrogenase (LDH) into the culture medium. Treatment with idebenone (10-1000 nM), a potent antioxidant in mitochondria, protected the hippocampal neurons against the Abeta1-40(10 microM)-induced neurotoxicity. To determine the morphological change in neurons during the Abeta1-40-induced cytotoxicity, the cells were immunostained with anti-MAP2 antibodies. After 4-day exposure to 10 microM Abeta1-40, the number of neurons was reduced, and the surviving neurons had an apparently reduced number of neurites which were shorter than those of control neurons. When idebenone was added to the culture medium with Abeta1-40, the number of surviving neurons was significantly increased, and their neurites were as long as seen in control culture. These results suggest that reactive oxygen species mediate neurotoxicity of Abeta1-40, and idebenone protects neurons against the Abeta1-40-induced neurotoxicity.

Topics: Amyloid beta-Peptides; Analysis of Variance; Animals; Antioxidants; Benzoquinones; Cell Count; Cell Survival; Cells, Cultured; Hippocampus; L-Lactate Dehydrogenase; Neurites; Neurons; Rats; Rats, Sprague-Dawley; Ubiquinone

Cerebral ischemia followed by oxygen reperfusion induces apoptosis in hippocampal neurons in stroke-prone spontaneously hypertensive rats (SHRSP) but not in Wistar Kyoto rats (WKY). The overproduction of oxygen-free radicals that occurs in the tissues of SHRSP is implicated in reoxygenation injury after hypoxia. Antioxidants inhibit reoxygenation injury in hippocampal slices, and temporal cortices in Alzheimer's disease increase sensitivity to oxygen-free radicals. Because this sensitivity may contribute to the development of the disease, we have studied hypoxia and oxygen reperfusion using cortical neurons isolated from WKY and SHRSP (at 15 days of gestation). We have tried to determine whether cortical neurons are damaged under these conditions, and whether neurons from SHRSP are more vulnerable than those from WKY. We have tried also to verify whether neuronal damage is minimized by vitamin E using the following techniques: (a) Trypan blue staining, (b) in situ staining of apoptosis, (c) ultrastructural examination, and (d) measurement of lactic dehydrogenase (LDH) activity in the bathing medium. Furthermore, we have examined the mechanisms involved in the development of neuronal damage and have studied ways of minimizing it. We demonstrated that 36 hours of hypoxia significantly increased the rate of cell death in SHRSP (p < 0.01), although 12 to 24 hours of hypoxia did not increase cell death in either WKY or SHRSP. In addition, 6 to 36 hours of hypoxia and 1.5 to 5 hours of oxygen reperfusion heavily damaged cells of both WKY and SHRSP, and most became apoptotic or necrotic. In contrast, cells incubated with 50 to 300 microg/ml of vitamin E remained intact, although 10 to 20 microg/ml of vitamin E did not totally preserve the cells. Moreover, vitamin E protected the neurons from high concentrations of sodium nitroprusside (nitric oxide donor) in a dose-dependent manner. Vitamin E, when added to the cells, increased in concentration in a time-dependent manner over a 24-hour period and in a dose-dependent manner below 200 microg/ml, and it was detected mostly in the mitochondria. We also demonstrated that serial treatments with allopurinol (a xanthine oxidase inhibitor) or superoxide dismutase preserved neurons during hypoxia and oxygen reperfusion. These data indicate that SHRSP neurons are weaker than WKY neurons in long-term hypoxia; oxygen radical generation occurs in the early minutes after reperfusion, and then the oxygen-free radicals cause hea

Topics: Animals; Antioxidants; Apoptosis; Benzoquinones; Cerebral Cortex; Cerebrovascular Disorders; Free Radical Scavengers; Genetic Predisposition to Disease; Hypoxia, Brain; Necrosis; Neurons; Nitric Oxide; Osmolar Concentration; Oxygen; Rats; Rats, Inbred SHR; Rats, Wistar; Reperfusion; Superoxide Dismutase; Ubiquinone; Vitamin E

We used phosphorus magnetic resonance spectroscopy (31P-MRS) to study in vivo brain and muscle bioenergetics in a male patient with Leber's hereditary optic neuropathy (LHON) and mtDNA mutation at 11,778 bp who developed spastic paraparesis with white matter lesions on brain MR imaging. The study was performed before and during treatment with idebenone (135 mg t.i.d.) and after withdrawal. Clinical amelioration and worsening were associated with parallel changes in brain and skeletal muscle bioenergetics following the administration or withdrawal of idebenone. Reversal of paraparesis by idebenone was paralleled by normalization of 31P-MRS, serum lactate and central motor conduction. Extra-ocular neurological dysfunction in LHON may be amenable to treatment by appropriate quinones.

Topics: Adult; Benzoquinones; Brain; Energy Metabolism; Follow-Up Studies; Humans; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; Male; Mitochondria, Muscle; Muscle, Skeletal; Neurologic Examination; Optic Atrophies, Hereditary; Paraparesis, Tropical Spastic; Phosphorus Isotopes; Ubiquinone

Topics: Adult; Antidepressive Agents; Benzoquinones; Brain; Depressive Disorder; DNA, Mitochondrial; Humans; Male; Point Mutation; Regional Blood Flow; RNA, Transfer; Tomography, Emission-Computed, Single-Photon; Ubiquinone

The effect of antioxidants and reducing agents on glutamate-induced cytotoxicity was examined using PC12 cells. The antioxidants vitamin E, idebenone, and selegiline protected cells against the cytotoxicity observed 24 h after exposure to 0.5 or 10 mM glutamate, as determined by lactate dehydrogenase leakage, even when added 3 h after glutamate. The reducing agents, glutathione (GSH) and dithiothreitol (DTT), also provided protection against the cytotoxicity of glutamate. Preincubation of PC12 cells with the antioxidants mentioned above, or the incubation with those antioxidants after exposure to glutamate for 3 h, prevented the reduction of viability caused by glutamate. Cystine uptake was inhibited by exposure of cells to glutamate, as determined by L-[35S]-cystine uptake. Incubation of cells with 0.5 or 10 mM glutamate caused a marked decrease in cellular GSH levels, not prevented by antioxidants. The activity of GSSG reductase was decreased by glutamate and this inhibition was reverted in the presence of the reducing agents GSH and DTT. These results indicate that glutamate toxicity on PC12 cells results from the inhibition of cystine uptake with consequent GSH depletion and oxidative stress, suggesting that antioxidants may reduce the cellular damage in pathologic conditions associated with excessive glutamate release.

Topics: Animals; Antioxidants; Benzoquinones; Cell Death; Cystine; Dithiothreitol; Glutamic Acid; Glutathione; Glutathione Reductase; Kinetics; L-Lactate Dehydrogenase; Oxidative Stress; PC12 Cells; Rats; Selegiline; Ubiquinone; Vitamin E

We observed in extra- and intracellular space accumulation of different fragments of amyloid precursor protein (APP) and apolipoprotein E (Apo E) in rat brain after cardiac arrest with long-term survival. Idebenone treatment did not affect APP and Apo E alterations in this condition.

Topics: Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Apolipoproteins E; Benzoquinones; Brain Ischemia; Cerebral Cortex; Female; Hippocampus; Rats; Rats, Wistar; Ubiquinone

Heat shock proteins (HSPs) are induced in the liver after warm ischemia/reperfusion and are thought to be markers of hepatocellular injury and oxidative stress.. The influence of variable periods of cold storage followed by reperfusion on the expression of HSP70 was studied in the isolated perfused pig liver. Organs were harvested and stored in histidine-tryptophan-ketoglutarate solution at 4 degrees C and then perfused (210 min) in a closed water bath (38 degrees C), which subjects the liver to fluctuating outer pressure. The role of energy depletion, reactive oxygen intermediates, Kupffer cells, and circulating leukocytes in HSP70 expression was determined.. HSP70 expression was not detectable in liver tissue before explantation or before reperfusion by Northern blot analysis using a pig HSP70 gene probe. HSP70 expression was observed after reperfusion depending on cold storage time. Kinetics of HSP70 expression monitored by reverse transcriptase polymerase chain reaction showed a rapid increase of mRNA within 1 hr, which was closely associated with delayed recovery of hepatocellular energy charge, as assessed by the ketone body ratio. The inactivation of Kupffer cells, the presence or absence of leukocytes, and the suppression of oxidative stress with the antioxidant idebenone, given during reperfusion, had no influence. However, feeding the animals with idebenone over 7 days before explantation led to a faster recovery of ketone body ratio, paralleled by a substantial suppression of HSP70 expression.. Our data show that HSP70 expression during reperfusion is mainly dependent on the preceding cold storage time and the consecutive delayed recovery of the hepatocellular energy charge.

Topics: Animals; Base Sequence; Benzoquinones; Cold Temperature; Conserved Sequence; DNA Primers; Energy Metabolism; Female; Gadolinium; Glucose; HSP70 Heat-Shock Proteins; Hypertonic Solutions; Ischemia; Ketone Bodies; Kinetics; Kupffer Cells; Liver; Male; Mannitol; Organ Preservation; Polymerase Chain Reaction; Potassium Chloride; Procaine; Reperfusion; RNA, Messenger; Swine; Transcription, Genetic; Ubiquinone

A 16-year-old boy with mitochondrial encephalomyopathy had seizures, short stature, muscle weakness, progressive hearing loss, mental retardation, and myoclonus. His cranial computed tomography showed progressive calcification in the basal ganglia and cerebral atrophy. Muscle biopsy revealed many ragged-red fibers with variable cytochrome c oxidase activity and some strongly succinate dehydrogenase-reactive blood vessels. Sequence analysis of the entire mitochondrial DNA revealed a novel point mutation in the tRNA-Thr gene at nucleotide pair 15915. Serum lactate levels were decreased by high-dose coenzyme Q10 (CoQ10) therapy. The spectral power density, a parameter of background activity on electroencephalography, was markedly improved after additional administration of idebenone. After initiation of combined CoQ10 and idebenone therapy, the clinical abnormalities did not progress for 16 months.

Topics: Adolescent; Benzoquinones; Brain; Coenzymes; DNA, Mitochondrial; Electroencephalography; Humans; Male; Mitochondrial Encephalomyopathies; Neurologic Examination; Point Mutation; RNA, Transfer, Thr; Sequence Analysis; Ubiquinone

Despite the large body of evidence for a major role of neutrophils and oxidant stress, the exact pathogenesis of the early ischemia/reperfusion injury after cold preservation of the liver is not well understood. The potential benefit of an antioxidant on metabolic liver function during reperfusion has been demonstrated in several studies.. We describe a cold storage/reperfusion damage model with isolated perfused pig livers, where the effects of neutrophils and idebenone, a recently developed benzoquinone antioxidant were studied. The integrity of sinusoidal endothelial cells (SEC) was estimated by hyaluronic acid concentration in perfusate and the expression of endothelial constitutive nitric oxide synthase (ecNOS) after reperfusion and compared to lipid peroxidation and antioxidant content.. Hyaluronic acid displayed the highest levels and ecNOS mRNA was most depressed in livers reperfused with neutrophils after 20 h cold storage; this was accompanied by an increase in lipid peroxidation (TBARS) and a breakdown of endogenous lipophilic antioxidants (alpha-tocopherol and coenzyme Q-10). These effects were attenuated, when neutrophils were excluded from reperfusion and almost completely abolished by the addition of 200 mumol/L idebenone.. These data suggest that a leukocyte-mediated damage based on reactive oxygen species markedly contributes to the reperfusion injury of SEC after cold preservation of the liver. Therefore, the presence of effective antioxidants in the early reperfusion phase may be beneficial for liver graft integrity.

Topics: Animals; Antioxidants; Benzoquinones; Cold Temperature; Depression, Chemical; Endothelium; Leukocytes; Liver; Oxidative Stress; Reperfusion Injury; Swine; Ubiquinone

The neuroprotective action of insulin-like growth factor I (IGF-I) was tested in immortalized hypothalamic GT1-7 cells exposed to reduced glutathione depleting agents, which cause oxidative stress and cell death. The extent of cell survival was assessed by either using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide cytotoxicity assay or counting at the fluorescence microscope GT1-7 cells prelabeled with fluorescent dyes selective for viable and dead cells. Treatments with buthionine sulfoximine (500 microns), diethylmaleate (1 mM), and ethacrynic acid (200 microns) caused diffuse GT1-7 cell death (40-60%). Exposure of the same cells to IGF-I (either before or concomitant to the toxic agent, depending on the drug used) significantly prevented neuronal death. This effect was rapid, concentration-dependent, maximal at concentrations of 25-50 ng/ml, and mimicked by IGF-II, fibroblast growth factor, and the potent antioxidant idebenone. In contrast, IGF-I, as well as idebenone, were completely ineffective in antagonizing the toxic effect produced by different concentrations of menadione. In conclusion, the present data demonstrate a protective role for IGF-I against glutathione depleting agents-induced damage in GT1-7 cells suggesting an antioxidant action of this growth factor in hypothalamic neurons.

Topics: Animals; Benzoquinones; Buthionine Sulfoximine; Cell Death; Cell Line, Transformed; Ethacrynic Acid; Hypothalamus; Insulin-Like Growth Factor I; Maleates; Methionine Sulfoximine; Mice; Mice, Transgenic; Neurons; Neuroprotective Agents; Radiation-Protective Agents; Ubiquinone; Vitamin K

We have studied the interaction of idebenone (2,3-dimethoxy-5-methy-6-(10-hydroxy)decyl-1,4-benzoquinone) with the energy-conserving complexes of the respiratory chain in beef heart mitochondria and compared its energetic efficiency with that of other analogs of coenzyme Q. Idebenone is a very effective substrate for succinate:Q reductase and ubiquinol:cytochrome c reductase, but it is clearly a poor substrate for NADH:Q reductase (complex I). Indeed, idebenone is a strong inhibitor of both the redox and proton pumping activity of complex I, showing effects in part similar to those of coenzyme Q-2. However, the mechanism of idebenone interaction with complex I may be different from that of Q-2 because of its different sensitivity to inhibitors. The possible relevance of the present findings to the therapeutic use of idebenone is discussed.

Topics: Animals; Benzoquinones; Cattle; Electron Transport; Energy Metabolism; Enzyme Inhibitors; In Vitro Techniques; Mitochondria, Heart; NAD(P)H Dehydrogenase (Quinone); Oxidation-Reduction; Substrate Specificity; Ubiquinone

We report a 36-year-old man with MELAS in whom a 5-month course of high-dose oral idebenone, a derivative of coenzyme Q10, increased markedly cerebral metabolic ratio of oxygen and oxygen extraction fraction without increased cerebral blood flow with PET. The results indicate that idebenone improves mitochondrial oxidative metabolism in the brain and suggest a therapeutic potential of idebenone for MELAS.

Topics: Adult; Benzoquinones; Brain; Humans; Magnetic Resonance Imaging; Male; MELAS Syndrome; Mitochondria; Tomography, Emission-Computed; Ubiquinone

The effect of idebenone on the serotonergic system was evaluated in the aging rat by measuring the kinetic constants of 3H-5HT and 3H-ketanserin binding sites in the cerebral cortex of rats at 3, 15 and 24 months of age following acute and subchronic administration of the drug. Idebenone displayed no in vitro affinity toward any population of serotonin receptors and did not modify their kinetic parameters after a single dose of 100 mg/kg, at any age tested. A subchronic treatment with the drug for 21 days at the dose of 30 mg/kg did not induce any relevant change in 3- and 15-month-old rats, whereas it significantly increased the density of both 3H-5HT and 3H-ketanserin binding sites in 24-month-old rats, where a lower number of receptors is detected as a consequence of aging. This effect was rather specific, since under the same experimental conditions no changes were detected in the density of cortical beta-adrenergic receptors in aged animals. In microdialysis studies, acute administration with idebenone did not affect 5HT and 5HIAA release at any age. Conversely, the pattern of serotonin metabolism was significantly modified in aged rats following repeated treatment with idebenone and was partially restored to a value similar to the one observed in young animals. These results suggest that idebenone, a putative neuroprotective agent which has been shown to improve brain metabolism in ischemic conditions, might also attenuate age-associated neuronal damage, acting probably on several neurotransmitter systems which undergo selective modification during aging.

Topics: Age Factors; Animals; Benzoquinones; Cerebral Cortex; Hippocampus; Ketanserin; Male; Microdialysis; Propanolamines; Rats; Rats, Wistar; Receptors, Adrenergic, beta; Receptors, Serotonin; Serotonin; Ubiquinone

The pharmacokinetics and tolerance of idebenone after single or repeated doses have been studied in young patients with mitochondrial encephalomyopathy.. No significant adverse effects were noted. In 3 out of 7 patients idebenone induced overall stimulation and improvement in arousal. Plasma concentrations of idebenone and its main metabolites were determined and the pharmacokinetic parameters of idebenone after single and repeated doses were estimated. During the single dose study, the mean plasma concentrations of idebenone and its main metabolites and mean pharmacokinetic parameters were comparable to published results (Cmax = 452.2 ng.ml-1, tmax = 2.3 h, AUC = 26 micrograms. ml-1.h, t1/2 beta = 16.5 h). During the repeated doses study, no significant difference was found between mean residual plasma concentrations of idebenone on Day 2 (47 ng.ml-1) and Day 5 (70.6 ng.ml-1), and mean t1/2 beta of idebenone after the single and after repeated dose studies, i.e., there was no evidence of accumulation. Although idebenone did not appear to accumulate during this study, the coadministration of anticonvulsants, often prescribed during mitochondrial encephalomyopathy, can affect its pharmacokinetics.

Topics: Adolescent; Anticonvulsants; Benzoquinones; Child; Child, Preschool; Drug Administration Schedule; Drug Therapy, Combination; Female; Humans; Male; Mitochondrial Encephalomyopathies; Phenobarbital; Ubiquinone

6-(10-Hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone) has been found to have a membrane-stabilizing activity in studies using lysosomes. Using dimyristoyl L-alpha-phosphatidylcholine (DMPC) as a substrate, the effects of idebenone and related benzoquinones on phospholipid digestion by phospholipase A2 (PLA2) was investigated. Free myristic acid, released from DMPC upon PLA2 treatment, was anthrylmethylated with 9-anthryldiazomethane (ADAM) and determined by reversed-phase HPLC. Idebenone and a related benzoquinone, 2,3-dimethoxy-5-methyl-6-(10-morpholinodecyl)-1, 4-benzquinone hydrochloride (QS-10.Mor), inhibited the hydrolysis of the substrate with PLA2 in a dose-dependent manner. It is suggested that the effect of idebenone on PLA2, in addition to its antioxidant activity lipid peroxidation, can be attributed to membrane-stabilizing activity.

Topics: Animals; Benzoquinones; Chromatography, High Pressure Liquid; Dimyristoylphosphatidylcholine; Elapid Venoms; Fatty Acids; Lipid Peroxidation; Pancreas; Phospholipases A; Phospholipases A2; Phospholipids; Swine; Ubiquinone

The ability of the benzoquinone coenzyme Q-10 or its derivative QSA-10 (idebenone) to protect against lipid peroxidation and protein damage mediated by the pro-oxidative system NADPH/ADP/Fe3+ was tested in a rat liver microsomal model incubated in University of Wisconsin (UW) or histidine-tryptophan-ketoglutarate (HTK) solutions. Lipid peroxidation, as followed by direct determination of lipid hydroperoxides and by monitoring of malondialdehyde equivalents, was 1.8-fold enhanced in HTK and 3-fold attenuated in UW compared with HEPES buffer. Function and integrity of microsomal enzymes were investigated using glutathione S-transferase and cytochrome P-450 IIIA activity as assessed by lidocaine N-deethylation to monoethylglycinexylidide as well as by Western blot analysis of the cytochrome P-450 IIIA protein. Glutathione S-transferase activity was reduced by about 70% in HEPES compared with 50% in HTK and 36% in UW. Cytochrome P-450 IIIA was inactivated by about 75% in HEPES and HTK, compared with 55% in UW. The enzyme inactivation was paralleled by a loss of immunoreactive cytochrome P-450 IIIA protein. Supplementation of HTK with 0.1 mumol/L QSA-10 offered complete protection against lipid peroxidation, compared with 100 mumol/L with Q-10. QSA-10 (20 mumol/L) prevented protein damage in both preservation solutions, whereas Q-10 (20 mumol/L) offered only partial protection in UW and had no effect in HTK. The use of QSA-10 during liver transplantation may therefore have the potential of increasing the efficacy of organ preservation, maintaining donor organ quality, and preventing reperfusion injury. It is suitable for human use and has energy-conserving properties in addition to its antioxidant nature.

Topics: Adenosine; Allopurinol; Animals; Antioxidants; Aryl Hydrocarbon Hydroxylases; Benzoquinones; Coenzymes; Cytochrome P-450 CYP3A; Cytochrome P-450 Enzyme System; Free Radicals; Glutathione; Insulin; Lipid Peroxidation; Male; Microsomes, Liver; Organ Preservation; Organ Preservation Solutions; Oxidoreductases, N-Demethylating; Raffinose; Rats; Rats, Wistar; Ubiquinone

Investigation of a maternal family of three generations of Leber's hereditary optic neuropathy (LHON) showed four affected and three unaffected individuals. Two of the four patients had recovered near-normal vision, one spontaneously, and one following treatment with idebenone, a quinol compound. One patient whose visual impairment persisted was a heavy consumer of alcohol and tobacco. Molecular genetic analysis of 12 known primary or secondary mutations in mitochondrial DNA (mtDNA) associated with LHON revealed only the 11778 mutation in a homoplasmic fashion with no secondary mutations. The variations in clinical outcome thus could not be explained by synergistically interacting secondary mutations in mtDNA. Environmental factors may play an etiologic role in the development of optic atrophy.

Topics: Adult; Aged; Alcohol Drinking; Benzoquinones; Child; DNA, Mitochondrial; Female; Humans; Male; Middle Aged; Mutation; Optic Atrophies, Hereditary; Pedigree; Prognosis; Smoking; Ubiquinone; Vision Disorders; Visual Acuity; Visual Fields

Topics: Adenosine; Allopurinol; Animals; Aryl Hydrocarbon Hydroxylases; Benzoquinones; Blotting, Western; Cytochrome P-450 CYP3A; Cytochrome P-450 Enzyme System; Free Radicals; Glutathione; Glutathione Transferase; Insulin; Lipid Peroxidation; Liver; Male; Malondialdehyde; Microsomes, Liver; Organ Preservation; Organ Preservation Solutions; Oxidoreductases, N-Demethylating; Probucol; Raffinose; Rats; Rats, Wistar; Ubiquinone

We investigated the effects of the combination of idebenone, an energy metabolism enhancer, and manidipine 2HCl, a dihydropyridine-derivative calcium antagonist, on neurological deficits and histological changes in the brain and kidneys of stroke-prone spontaneously hypertensive rats (SHRSP) with cerebrovascular lesions (stroke). The SHRSP were kept on a 1% NaCl solution as their drinking water to synchronize the onset of stroke. After the onset of stroke symptoms, the salt solution was replaced with tap water. On the day following the onset of stroke, idebenone (50 mg/kg), manidipine 2HCl (2 mg/kg) or a combination of idebenone (50 mg/kg) and manidipine 2HCl (2 mg/kg) was administered orally once a day for 3 weeks. In the combination group and manidipine 2HCl-treated group, the neurological deficits after the onset of stroke were ameliorated during the entire experimentalperiod. Especially, the combination significantly decreased the number of days with severe neurological deficits as compared to the control group. The combination and manidipine 2HCl significantly recovered the decrease in body weight and ameliorated the increase of brain weight, which was mainly caused by edema, significantly as compared to the control group. Manidipine 2HCl ameliorated the histological changes in the brain. In the combination group, the histological changes in both the brain and the kidneys were ameliorated. In conclusion, the combination of idebenone and manidipine 2HCl significantly ameliorated the neurological deficits and the histological changes in the brain and the kidney of SHRSP with stroke as compared to each individual treatment. We concluded that manidipine 2HCl enhances the therapeutic effect of idebenone in the treatment of cerebrovascular diseases.

Topics: Administration, Oral; Animals; Benzoquinones; Brain; Calcium Channel Blockers; Cerebrovascular Disorders; Dihydropyridines; Drug Combinations; Drug Synergism; Drug Therapy, Combination; Kidney; Male; Nitrobenzenes; Piperazines; Rats; Rats, Inbred SHR; Ubiquinone

Persistent stimulation of energy consumption, induced by depolarization with veratridine, mimics a condition of abnormally enhanced energy demand and causes an increase in the oxygen consumption rate (QO2) and in the interconversion of pyruvate dehydrogenase complex (PDHc) into its active form. Wistar rats at the age of 26 months do not show alterations of QO2 and the ability of veratridine to increase QO2 in comparison with 6 month-old animals whereas the active form of PDHc is slightly but significantly reduced. Idebenone, a ubiquinone-like molecule (1 microM), does not affect the QO2 or PDHc activation state in resting conditions but attenuates the veratridine-challenged increase in QO2 at all the ages tested and attenuates the increase in the percentage of PDHa reaching statistical significance in 26-month-old rats. At higher concentration (10 microM) idebenone totally abolishes the veratridine-induced increase in PDHa also in the 6 month-old rats. At the lower concentration, the drug does not affect the increase in QO2 induced by an uncoupler of oxidative phosphorylation. The results obtained suggest a protective effect of idebenone on the cerebral tissue against stressful conditions; this action may be exerted at the level of some mitochondrial component and/or on the Na+ homeostasis.

Topics: Adenosine Triphosphate; Aging; Animals; Benzoquinones; Cerebral Cortex; Energy Metabolism; Enzyme Activation; Male; Oxidation-Reduction; Oxygen Consumption; Pyruvate Dehydrogenase Complex; Rats; Rats, Wistar; Sodium-Potassium-Exchanging ATPase; Synaptosomes; Ubiquinone; Veratridine

Effect of idebenone on the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-selective glutamate receptor was evaluated using Xenopus oocytes injected with RNAs encoding mouse alpha 1 and alpha 2 AMPA receptors. Concanavalin A augmented current responses of the RNA-injected oocytes to glutamate, kainate, and AMPA and these responses were further potentiated by 100 microM idebenone. The minimum concentration of idebenone that gave a significant potentiation was 10 microM for glutamate. These results suggest that idebenone acts on AMPA-selective glutamate receptor channels composed of alpha 1 and alpha 2 subunits.

Topics: alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; Animals; Benzoquinones; Concanavalin A; Dose-Response Relationship, Drug; Electrophysiology; Female; Glutamates; Glutamic Acid; Oocytes; Receptors, Glutamate; RNA, Complementary; Ubiquinone; Xenopus laevis

The effects of cerebral metabolism-improving drugs on NADPH diaphorase activity in the mouse brain were studied, and we found that diaphorase activity in the post-mitochondrial fraction of brain homogenate was enhanced by idebenone in a concentration-dependent manner. Histochemical studies also indicated that diaphorase staining was intensified by idebenone at the same concentration. These results suggest that idebenone may stimulate the production of nitric oxide, probably through its direct action on nitric oxide synthase, thus producing its protective action on neurological disorders due to cerebral hypoxia or ischemia as a consequence of dilating the cerebral blood vessels.

Topics: Amino Acid Oxidoreductases; Animals; Benzoquinones; Brain; Brain Ischemia; Cerebral Cortex; Choroid Plexus; Dose-Response Relationship, Drug; Histocytochemistry; Hypoxia; In Vitro Techniques; Male; Mice; NADPH Dehydrogenase; Nitric Oxide; Nitric Oxide Synthase; Ubiquinone

The novel free radical scavenger and electron-trapping agent, idebenone, protects cultured cortical neurons against necrotic degeneration induced by either a brief exposure to N-methyl-D-aspartate (NMDA) or a prolonged exposure to kainate. As opposed to the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]- cyclohepten-5,10-imine hydrogen maleate (MK801), idebenone rescued cortical neurons even when applied 30 min after the NMDA pulse, suggesting that the drug interferes with the chain of toxic reactions triggered by an excessive stimulation of excitatory amino acid receptors.

Topics: Animals; Benzoquinones; Cells, Cultured; Cerebral Cortex; Dizocilpine Maleate; Mice; N-Methylaspartate; Nerve Degeneration; Neurons; Neuroprotective Agents; Neurotoxins; Time Factors; Ubiquinone

Glutamate-induced glutathione depletion in immature embryonic cortical neurons has been shown to lead to oxidative stress and cell death. We have used this in vitro model to investigate the mechanism(s) by which free radicals induce neuronal degeneration. We find that glutathione depletion leads to hyper-condensation and fragmentation of chromatin into spherical or irregular shapes, a morphologic signature of apoptosis. These morphologic changes are accompanied by laddering of DNA into multiple oligonucleosomal fragments and can be prevented by the antioxidants idebenone and butylated hydroxyanisole. Cell death induced by glutathione depletion can also be prevented by inhibitors of macromolecular synthesis. Taken together, these observations suggest that oxidative stress can induce apoptosis in neurons.

Topics: Analysis of Variance; Animals; Antioxidants; Apoptosis; Benzoquinones; Butylated Hydroxyanisole; Cerebral Cortex; Chromatin; Cycloheximide; Dactinomycin; DNA Damage; Embryo, Mammalian; Free Radicals; Glutamates; Glutamic Acid; Glutathione; Neurons; Neurotoxins; Rats; Rats, Sprague-Dawley; Ubiquinone

Nerve growth factor (NGF) plays an important role in the survival and maintenance of cholinergic neurons in the central neuronal system. Since this factor does not cross the blood-brain barrier and is easily metabolized by peptidases when administered peripherally, it can be used for medical treatment only when directly injected into the brain. We report here that repeated oral administration of the stimulators for the NGF synthesis, idebenone and propentofylline, produced a significant recovery of the reduced NGF content in the frontal and parietal cortices of aged rats. These compounds also improved deficits of performance in water maze, passive avoidance and habituation tasks in basal-forebrain-lesioned rats. These results suggest that the use of the stimulators for the NGF synthesis may provide a therapeutic approach to cholinergic dysfunction.

Topics: Administration, Oral; Aging; Analysis of Variance; Animals; Benzoquinones; Brain; Choline O-Acetyltransferase; Cognition; Humans; Learning; Male; Memory; Nerve Growth Factors; Rats; Rats, Wistar; Ubiquinone; Xanthines

Nerve growth factor plays an important role in the survival and maintenance of cholinergic neurons in the central neuronal system. In senile dementia of the Alzheimer type, learning and memory are impaired by the loss of neurons in the magnocellular cholinergic neuronal system. It is therefore, of interest to investigate the role of nerve growth factor in this degenerative disorder. Since nerve growth factor does not cross the blood-brain barrier and is easily metabolized by peptidases when administered peripherally, it can be used for medical treatment only when directly injected into the brain. We demonstrate here that the oral administration of idebenone, a potent in vitro nerve growth factors synthesis stimulator, induced an increase in nerve growth factor protein and mRNA, and in choline acetyltransferase activity, in basal forebrain lesioned rats, but not in intact rats. Idebenone also ameliorated the behavioral deficits in habituation, water maze, and passive avoidance tasks in these animals. These results suggest that idebenone stimulated nerve growth factor synthesis in vivo and ameliorates the behavioral deficits which were accompanied with the recovery of the reduced choline acetyltransferase activity in the basal forebrain-lesioned rats.

Topics: Animals; Avoidance Learning; Base Sequence; Benzoquinones; Brain; Brain Chemistry; Choline O-Acetyltransferase; Habituation, Psychophysiologic; Learning; Male; Memory; Molecular Sequence Data; Motor Activity; Nerve Growth Factors; Prosencephalon; Rats; Rats, Wistar; RNA, Messenger; Space Perception; Ubiquinone

We examined the protective effects of idebenone, 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone, on the cytotoxicity of oxidatively-modified low density lipoprotein (oxLDL), using cultured vascular endothelial cells from fetal bovine aorta. When the cells were incubated with idebenone, the toxicity of oxLDL was inhibited dose-dependently (10(-7)-10(-5) M). When cells were preincubated with idebenone, the toxicity of oxLDL was inhibited only at a high concentration (10(-5) M). However, idebenone had no significant effects on copper-induced modification of LDL. The protective effects of idebenone on oxLDL-induced endothelial toxicity may be beneficial for the inhibition of the development of atherosclerosis in the brain and other arterial systems.

Topics: Animals; Aorta, Thoracic; Benzoquinones; Butylated Hydroxytoluene; Cattle; Cell Survival; Cells, Cultured; Copper; Dose-Response Relationship, Drug; Endothelium, Vascular; Humans; Kinetics; L-Lactate Dehydrogenase; Lipid Peroxidation; Lipoproteins, LDL; Malondialdehyde; Thiobarbituric Acid Reactive Substances; Ubiquinone; Vitamin E

Idebenone (6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone) is a benzoquinone that has been shown to improve cognitive function in animals subjected to cerebral ischemia and in rats with lesions of the basal forebrain cholinergic system. Because the cognitive deficits observed in aged rats have been associated with decreased cerebral blood flow and basal forebrain cholinergic dysfunction, it was hypothesized that IDE might improve cognition in aged animals. In the present study, the effects of idebenone on cognitive function in aged Long-Evans rats were assessed using a battery of tests that evaluated attention, habituation, and spatial learning. Selective attention was assessed using an overshadowing paradigm, where IDE (30 mg/kg, IP) was injected 30 min prior to compound cue exposure. IDE enhanced the overshadowing effect in aged rats. The Morris water maze was used to assess spatial learning, where IDE (3 mg/kg, IP) was injected daily throughout the course of training. IDE did not improve the impaired performance of aged rats in the Morris task. Habituation was tested by measuring recovery from gustatory neophobia. IDE (30 mg/kg, IP) was injected 30 min prior to the first exposure to the novel taste. IDE normalized habituation rate in aged rats. It was concluded that IDE improves some forms of acquisition in aged rats, and may do so by decreasing general reactivity to novel stimuli.

Topics: Aging; Animals; Anxiety; Attention; Benzoquinones; Cognition; Environment; Habituation, Psychophysiologic; Learning; Male; Mental Processes; Rats; Space Perception; Taste; Ubiquinone

The effect of idebenone on the changes in adenosine and nucleotide metabolism occurring in hippocampal slices after ischemia-like conditions (superfusion with glucose-free Krebs solution gassed with 95% N2-5% CO2) and during reperfusion with normal Krebs solution was investigated by measuring adenosine and inosine outflow, and adenosine and adenine nucleotide levels by HPLC. Five minutes of ischemia-like conditions brought about an 8- and 4-fold increase in adenosine and inosine outflow 10 min after reperfusion and a 75% increase in the tissue level of adenosine, a 40% decrease in ATP, and a 50% increase in AMP at the end of the ischemic period. Ten minutes after reperfusion, ATP and AMP returned to control values. Idebenone (25-100 microM) brought about a concentration-dependent increase in adenosine and inosine outflow evoked by ischemia-like conditions. Idebenone (50 microM) also increased the adenosine content in hippocampal slices after both ischemia (+150%) and reperfusion (+320%). An 82% increase in ADP, 174% in AMP, and 56% in the total sum of nucleotides, 10 min after reperfusion were found in idebenone treated slices. These results suggest that idebenone enhances adenosine formation after ischemia-like conditions from sources other than AMP, and improves phosphorylating activity during reperfusion. Idebenone, by increasing adenosine and total nucleotide levels, may protect brain tissue from ischemic damage.

Topics: Adenine Nucleotides; Adenosine; Adenosine Diphosphate; Adenosine Monophosphate; Adenosine Triphosphate; Animals; Benzoquinones; Brain Ischemia; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Hippocampus; In Vitro Techniques; Inosine; Male; Rats; Rats, Wistar; Ubiquinone

The relationship between nerve growth factor (NGF) and senile dementia of the Alzheimer type is of interest. We demonstrate here that the oral administration of idebenone, a stimulator of NGF synthesis in vitro, produced recovery of reduced NGF content in aged rat brain. Twenty-one-day successive administration of idebenone produced significant recovery of reduced NGF content in the frontal cortex and parietal cortex of aged rats. These results suggest that NGF content in the brain is low in aged rats and that oral administration of idebenone leads to a recovery of this reduction.

Topics: Administration, Oral; Aging; Animals; Benzoquinones; Brain; Choline O-Acetyltransferase; Frontal Lobe; Hippocampus; Male; Nerve Growth Factors; Olfactory Bulb; Organ Specificity; Parietal Lobe; Rats; Rats, Wistar; Reference Values; Ubiquinone

Effects of OM-853 on behavioral responses in the forced swim test were studied. OM-853 significantly reduced the duration of immobility without any change in the exploratory activity. Imipramine also reduced the duration of immobility, but idebenone did not. On the other hand, vinpocetine enhanced the duration with a suppressive effect on ambulation. The anti-immobility effect of OM-853 was reversed by pretreatment with haloperidol. These results demonstrate that the effect of OM-853 on the swim test is different from that of idebenone and vinpocetine. Furthermore, the present results suggest that OM-853 may exert its anti-immobility activity through facilitated transmission of the dopaminergic and/or adrenergic systems.

Topics: Animals; Behavior, Animal; Benzoquinones; Haloperidol; Imipramine; Immobilization; Male; Motor Activity; Phosphodiesterase Inhibitors; Rats; Rats, Wistar; Swimming; Ubiquinone; Vinca Alkaloids

The protective effects of BMY-21502 (1-[[1-[2-(trifluoromethyl)-4-pyrimidinyl]-4-piperidinyl]methyl]-2- pyrrolidinone) against cerebral anoxia were investigated using various models in mice, in comparison with those of other cerebroactive drugs. Oral administration of BMY-21502 (10-100 mg/kg) significantly prolonged the survival time in KCN (2.4 mg/kg, i.v.)-induced anoxia. Oxiracetam and idebenone exerted similar but weak protection at doses above 100 mg/kg, p.o. and only at a dose of 100 mg/kg, p.o., respectively. Significant protection by BMY-21502 against moderate hypobaric hypoxia was observed at doses of 30 and 100 mg/kg, p.o. Idebenone (100 and 300 mg/kg, p.o.) significantly prolonged the survival time of mice in this model, but oxiracetam (30-300 mg/kg, p.o.) did not. Oral administration of all of these drugs (BMY-21502, 3-300 mg/kg; Oxiracetam, 100-1000 mg/kg; Idebenone, 100-1000 mg/kg) failed to increase the number of gasps and the duration of gasping in the decapitated head of mice as a complete ischemic model. The anti-anoxic effect of BMY-21502 in the KCN-anoxia model was blocked by pretreatment with scopolamine. These findings suggest that BMY-21502 has an anti-anoxic action superior to those of the other cerebroactive drugs used, and activation of the CNS cholinergic system is involved as one of the causative mechanisms for the anti-anoxic effect of BMY-21502.

Topics: Animals; Atmospheric Pressure; Benzoquinones; Brain Ischemia; Disease Models, Animal; Hypoxia, Brain; Male; Mice; Potassium Cyanide; Psychotropic Drugs; Pyrimidines; Pyrrolidines; Pyrrolidinones; Scopolamine; Ubiquinone

Topics: Administration, Oral; Benzoquinones; Child; DNA Mutational Analysis; Humans; Male; Optic Atrophies, Hereditary; Ubiquinone

Effect of WEB 1881 FU (nebracetam) on hypoxia and ischemia-induced impairment of 2-deoxyglucose (2DG) uptake and CA1 field potentials induced by hypoxia and hypoxia/hypoglycemia (ischemia) in rat brain slices was evaluated and compared to the findings obtained with pentobarbital and idebenone. Hippocampal and cortical slices were exposed to 15-20 min of ischemia, and then these slices were returned to oxygenated and glucose-containing buffer for 6 hr. Ischemia reduced both 30 mM KCl-induced 2DG uptake and CA1 field potentials elicited by the stimulation of Schaffer collaterals in the hippocampus. Pretreatment of nebracetam at 1 mM or pentobarbital at 0.1 mM attenuated a decline of 2DG uptake and CA1 field potentials under the condition of ischemia. In addition, nebracetam and pentobarbital relatively recovered the increase of 2DG uptake in the hippocampus under hypoxia for 45 min. Furthermore, these drugs also attenuated the decline of 2DG uptake induced by 10 mM glutamate for 20 min. However, treatment with idebenone did not recover the deficit of 2DG uptake and CA1 field potential. The present result suggests that nebracetam and pentobarbital exert neuroprotective actions against not only ischemia but also glutamate toxicity.

Topics: Animals; Benzoquinones; Brain Ischemia; Cerebral Cortex; Deoxyglucose; Electrophysiology; Evoked Potentials; Glutamates; Glutamic Acid; Hippocampus; Hypoxia; In Vitro Techniques; Male; Parasympathomimetics; Pentobarbital; Pyrrolidinones; Rats; Rats, Inbred Strains; Ubiquinone

Bifemelane hydrochloride (bifemelane), idebenone and indeloxazine hydrochloride (indeloxazine) are used clinically to reduce apathy and other emotional disturbances in patients with cerebrovascular disease. In gerbil brains, ischemia affects many monoaminergic neurotransmitters and their metabolites. In the present study, the effects of treatment with bifemelane, idebenone and indeloxazine on ischemia-induced changes in monoamines and their metabolites were studied in ischemic gerbil brains. Although these drugs had no effect on the monoaminergic neurotransmitters or their metabolites in sham-operated animals, in the ischemic brains both dopamine and serotonin turnovers were abnormal after idebenone or indeloxazine treatment. Bifemelane, in contrast, tended to correct the ischemia-induced changes in the dopaminergic and serotonergic systems in the cerebral cortex, hippocampus and thalamus + midbrain. From the present results and those in previous reports, we conclude that bifemelane is more appropriate than idebenone or indeloxazine as a treatment for the ischemia-induced changes in monoaminergic neurotransmitter systems.

Topics: Animals; Benzhydryl Compounds; Benzoquinones; Biogenic Monoamines; Brain Chemistry; Brain Ischemia; Dopamine; Gerbillinae; Hydroxyindoleacetic Acid; Morpholines; Nerve Tissue Proteins; Norepinephrine; Serotonin; Ubiquinone

The effects of various nootropic candidates on mescaline-induced head-twitches were studied in mice. The number of head-twitches induced by mescaline (100 mg/kg, s.c.) was significantly reduced by idebenone (32 and 100 mg/kg, i.p.), minaprine (0.32-10 mg/kg, p.o.) and nebracetam (100 mg/kg, p.o.). Cholinesterase inhibitors such as tetrahydroaminoacridine (1 and 10 mg/kg, p.o.), NIK-247 (10 and 18 mg/kg, p.o.) and physostigmine (0.32 mg/kg, i.p.) also suppressed the head-twitch response to mescaline. These results suggest that the direct or indirect cholinergic-activating effects of these drugs may be involved in inhibiting mescaline-induced head-twitches.

Topics: Animals; Antidepressive Agents; Behavior, Animal; Benzoquinones; Cholinesterase Inhibitors; Male; Mescaline; Mice; Mice, Inbred Strains; Psychotropic Drugs; Pyridazines; Pyrrolidinones; Ubiquinone

A high-performance liquid chromatographic determination of idebenone, a new cerebral metabolism-improving agent, in rat serum and brain has been developed. After separation of idebenone on a reversed-phase column, idebenone was reduced once in a platinum catalyst reduction column connected on-line, then monitored quantitatively by electrochemical detection. A linear relationship between the peak-height ratio of idebenone to the internal standard and idebenone concentration was observed in the range 0.015-50 ng with a detection limit of 5 pg (signal-to-noise ratio = 5). This method was satisfactorily rapid and sensitive, and was successfully applied to the determination of idebenone in rat serum and brain tissues.

Topics: Animals; Benzoquinones; Brain; Brain Chemistry; Catalysis; Chromatography, High Pressure Liquid; Electrochemistry; Indicators and Reagents; Male; Oxidation-Reduction; Platinum; Rats; Rats, Inbred Strains; Ubiquinone; Vitamin K

The effect of idebenone, an agent improving cerebral metabolism, on catecholamine secretion was examined using primary cultures of bovine adrenal chromaffin cells. Catecholamine secretion evoked by acetylcholine was markedly inhibited by idebenone, and this effect was concentration-dependent. In contrast, other cerebral metabolism-improving agents, such as hopantenate and propentofylline, failed to cause any significant effect on the secretion in the same concentration range. Furthermore, idebenone inhibited the secretion evoked by high K+, veratridine, and Ba2+, but failed to inhibit the secretion evoked by the Ca(2+)-ionophore A23187. Idebenone also inhibited the radioactive Ca2+ uptake stimulated by acetylcholine or high K+ under the conditions in which its inhibitory action on the secretion was observed. Nifedipine, a typical voltage-dependent Ca2+ channel blocker, inhibited the secretion evoked by high K+, and this inhibitory action on the secretion was markedly reduced by the presence of idebenone. The present results suggest that idebenone may inhibit the influx of extracellular Ca2+ into the cells presumably through its blocking action on the voltage-dependent Ca2+ channels, resulting in the inhibition of catecholamine secretion in the adrenal chromaffin cell.

Topics: Acetylcholine; Adrenal Medulla; Animals; Benzoquinones; Calcium; Calcium Channel Blockers; Calcium Channels; Catecholamines; Cattle; Cells, Cultured; Chromaffin System; Ubiquinone

The effect of oxiracetam (CGP 21690E, CAS 62613-82-5) on cerebrovascular impairment was investigated in rats. 1. After injection of tranylcypromine (a MAO inhibitor), spontaneously hypertensive rats (SHR) which had been previously infused with norepinephrine (NE) for 14 days displayed stroke-related behaviour including kangaroo-like posture, seizures and death. Administration of oxiracetam at doses of 400 and 800 mg/kg/d p.o. for 14 days before tranylcypromine injection inhibited the stroke-related behaviour. 2. Bilateral common carotid and vertebral artery occlusion induced electroencephalogram (EEG) flattening, the EEG recovering gradually after re-perfusion of cerebral blood flow. Oxiracetam administered after the re-perfusion at a dose of 100 mg/kg, i.v. accelerated the recovery. This facilitatory effect was not seen when either piracetam (50 and 100 mg/kg i.v.) or idebenone (50 and 100 mg/kg i.v.) were administered. 3. Occlusion of middle cerebral artery produced cerebral infarction and disturbed the circadian rhythm of spontaneous motor activity with an relative increase of activity in the light period. Treatment with oxiracetam (400 mg/kg/d p.o.) for 14 days after the occlusion showed a tendency to an improvement in the disturbed circadian rhythm but did not influence the size of brain infarction. From these results, oxiracetam is thought to have a protective effect in cerebrovascular impairment.

Topics: Animals; Behavior, Animal; Benzoquinones; Blood Pressure; Cerebral Arteries; Cerebral Infarction; Cerebrovascular Disorders; Electroencephalography; Male; Motor Activity; Norepinephrine; Piracetam; Pyrrolidines; Rats; Rats, Inbred SHR; Rats, Inbred Strains; Tranylcypromine; Ubiquinone

Topics: Adrenal Glands; Animals; Benzoquinones; Brain; Carbon Radioisotopes; Catecholamines; Cattle; Cells, Cultured; Chromaffin System; Stimulation, Chemical; Tyrosine; Ubiquinone

The antioxidative effect of idebenone was studied in isolated mitochondria from the rat heart. Variables for dynamic microstructure, membrane viscosity and wobbling angle of phospholipids, were measured by means of a nanosecond time-resolved fluorometer. Exposure of isolated cardiac mitochondria to oxidative conditions in vitro caused significant alterations in lipid peroxidation, wobbling angle of phospholipids and membrane viscosity. Exposure of mitochondria to oxidative conditions after idebenone pretreatment resulted in no significant alterations in membrane viscosity and wobbling angle of phospholipids. Alterations in these variables seemed to be related to the amount of peroxidized lipid. Protection of phospholipids against peroxidation by antioxidative substances is effective in maintaining nearly normal physical properties in the dynamic microstructure of cardiac mitochondrial membranes.

Topics: Animals; Antioxidants; Benzoquinones; In Vitro Techniques; Lipid Peroxidation; Male; Malondialdehyde; Mitochondria, Heart; Oxidation-Reduction; Phospholipids; Rats; Rats, Inbred Strains; Ubiquinone; Viscosity

Age-related changes in the acquisition and retention of memory based on the step-through active avoidance response were studied in rats and the effects of cholinergic drugs and cerebral metabolic activators on memory impairment in old rats were also tested. Six- and 12-month-old rats showed lower rates of acquisition of the active avoidance response than did 2-month-old rats. In addition, the retention of the active avoidance response in 6- and 12-month-old rats diminished rather rapidly compared with that observed in 2-month-old rats. Intraventricular injection of acetylcholine at doses of 20 and 50 ng caused a significant improvement of memory impairment in old rats. Physostigmine and arecoline also caused a significant ameliorating effect at doses of 0.02 and 0.05 mg/kg i.p. and 0.2 and 0.5 mg/kg i.p., respectively. Hopantenate calcium (100 mg/kg, p.o.), idebenone (20 and 50 mg/kg, i.p.), indeloxazine (50 mg/kg, p.o.) and DM-9384 (30 mg/kg, p.o.) also proved useful to improve memory impairment in old rats.

Topics: Acetylcholine; Aging; Animals; Benzoquinones; Brain; Central Nervous System Agents; gamma-Aminobutyric Acid; Learning; Male; Memory Disorders; Morpholines; Pantothenic Acid; Parasympathomimetics; Pyrrolidinones; Rats; Rats, Inbred Strains; Ubiquinone

Previous studies with the N18-RE-105 neuronal-like cell line and primary cortical cultures demonstrate that glutamate can produce a calcium-dependent, delayed form of neuronal degeneration that results from its competitive inhibition of cystine transport, which leads to cellular glutathione depletion and death by oxidative stress. Idebenone, a centrally active antioxidant used to treat multiinfarct dementia, protects cells from this form of glutamate-induced cytotoxicity in vitro. In the present study, we have examined the effects of systemic treatment with idebenone on the neurotoxic consequences of intrastriatal injection of kainic acid, quisqualic acid, or quinolinic acid, an NMDA receptor agonist, on neuronal degeneration. Striatal damage was assessed by quantitative neurochemistry with measurement of choline acetyltransferase activity and glutamate decarboxylase activity, by histochemical analysis for acetylcholinesterase and NADPH diaphorase staining and by behavioral assessment of circling produced by systemic apomorphine treatment 10 days after the unilateral lesion. The results indicate that treatment with idebenone provides significant protection against the neuronal degeneration induced by intrastriatal injection of kainic acid and quisqualic acid, but not the NMDA receptor agonist, quinolinic acid. The results suggest that oxidative stress may contribute to the proximate cause of neuronal degeneration induced by quisqualate and by kainate receptor agonists and that the mechanisms of neuronal degeneration caused by quisqualate/kainate receptor agonists differ from those associated with NMDA receptor agonists.

Topics: Animals; Apomorphine; Benzoquinones; Choline O-Acetyltransferase; Corpus Striatum; Glutamate Decarboxylase; Histocytochemistry; Kainic Acid; Kinetics; Male; Motor Activity; NADPH Dehydrogenase; Nerve Degeneration; Oxadiazoles; Pyridines; Quinolinic Acid; Quinolinic Acids; Quinones; Quisqualic Acid; Rats; Rats, Inbred Strains; Ubiquinone

Using the N18-RE-105 neuroblastoma X retina cell line, we previously described Ca2(+)-dependent quisqualate-type glutamate toxicity caused by the inhibition of high-affinity cystine uptake, leading to glutathione depletion and accumulation of cellular oxidants. We now demonstrate that primary cultures of rat cortical neurons (E17; 24-72 h in culture), but not glia, also degenerate when exposed to culture medium with reduced cystine or containing competitive inhibitors of cystine uptake, including glutamate. At this developmental stage, neurotoxicity did not occur as a consequence of continuous exposure to glutamate receptor subtype agonists, N-methyl-D-aspartate, kainate, or 2(RS)-amino-3-hydroxy-5-methyl-4-isoxazolepropionate. However, those that inhibited neuronal cystine uptake--quisqualate, glutamate, homocysteate, beta-N-oxalyl-L-alpha,beta-diaminopropionic acid, and ibotenate--were neurotoxic. Toxicity related to quisqualate did not correlate with the development of quisqualate-stimulated phosphatidylinositol turnover. The toxic potencies of glutamate, quisqualate, and homocysteate were inversely proportional to the concentration of cystine in the medium, suggesting that they competitively inhibit cystine uptake. Autoradiographic analysis of the cellular localization of L-[35S]cystine uptake indicated that embryonic neurons have a high-affinity transport system that is sensitive to quisqualate, whereas non-neuronal cells in the same cultures have a low-affinity system that is insensitive to quisqualate but potently blocked by D-aspartate and glutamate. Exposure to glutamate or homocysteate resulted in a time-dependent depletion of the cellular antioxidant glutathione. The centrally acting antioxidant idebenone and alpha-tocopherol completely blocked the neurotoxicity resulting from glutamate exposure. We propose that competitive inhibition of cystine transport and reduction of extracellular cystine levels result in neuronal cell death due to accumulation of cellular oxidants.

Topics: Animals; Benzoquinones; Biological Transport; Carbachol; Cell Survival; Cells, Cultured; Cerebral Cortex; Cystine; Fetus; Glutamates; Homocysteine; In Vitro Techniques; Neurons; Oxadiazoles; Quinones; Quisqualic Acid; Rats; Ubiquinone; Vitamin E

Previously we reported that astroglial cells cultured from mouse brain synthesize and secrete nerve growth factor (NGF) and that, in quiescent cells, catecholamines markedly increase the NGF content in the conditioned medium (CM). We wished to further assess the structural properties required for exhibition of such effect of compounds containing a ring structure analogous to that of catechol on astroglial NGF synthesis. During our study, we found that hydroquinone, which was confirmed not to stimulate NGF synthesis in mouse fibroblast cells in another of our investigations, is a potent stimulator of NGF synthesis in astroglial cells and that 1,4-benzoquinone, an oxidized form of hydroquinone, is a more effective stimulator than hydroquinone itself. In addition, the results of experiments with 1,2-benzoquinone derivatives indicated that the presence of a long aliphatic side chain in the molecule eliminates the stimulatory effect of 1,4-benzoquinone on NGF synthesis in astroglial cells.

Topics: Animals; Astrocytes; Benzoquinones; Brain; Catechols; Cells, Cultured; Hydroquinones; Mice; Mice, Inbred ICR; Molecular Structure; Nerve Growth Factors; Quinones; Resorcinols; Structure-Activity Relationship; Ubiquinone

Using a repeated acquisition procedure in a three-panel runway apparatus, the effects of minaprine on the impairment of working memory produced by scopolamine, ethylcholine aziridinium ion (AF64A) or cerebral ischemia were investigated in rats. Minaprine (3.2-32 mg/kg IP) as well as idebenone (10-100 mg/kg IP) and physostigmine (0.1-0.32 mg/kg IP) dose-dependently reduced the increase of errors (pushes made on the two incorrect panels located at each choice point) induced by 0.56 mg/kg IP scopolamine. Cerebral ischemia for 5 min caused a significant increase of errors in the runway task. Minaprine at 3.2 and 10 mg/kg administered IP immediately after blood recirculation and again 30 min before the runway test conducted 24 h after ischemia, significantly reduced increases in errors expected to occur after 5 min of ischemia. Physostigmine 0.1 mg/kg similarly attenuated the increase in errors in ischemic rats. However, minaprine at doses up to 32 mg/kg IP failed to reduce the increase of errors induced by AF64A 2.5 nmol injected into the dorsal hippocampus. These findings suggest that minaprine exerts an ameliorating effect on amnesia produced by scopolamine and cerebral ischemia, probably through mediation of its stimulant action on central cholinergic systems.

Topics: Animals; Aziridines; Benzoquinones; Brain Ischemia; Choline; Hippocampus; Injections; Male; Memory; Physostigmine; Psychomotor Performance; Pyridazines; Quinones; Rats; Rats, Inbred Strains; Scopolamine; Ubiquinone

Effect of WEB 1881 FU on hypoglycemia/hypoxia-induced brain damage in rats was evaluated and compared to findings obtained with idebenone. We used an in vitro model that facilitated the direct monitoring of dopamine release from striatal slices. The response to high K+ stimulation under perfusion of the slices with D-glucose-free Ringer solution (hypoglycemia) decreased at 40 min, and then practically disappeared. WEB 1881 FU at 10(-6) M or idebenone at 10(-6) M significantly protected against impairment of the striatal responses under the conditions of hypoglycemia. Hypoglycemic injury, evidenced by a remarkable neuron loss, necrosis and spongyosis was also ameliorated by these drugs. WEB 1881 FU at 10(-6) M had a protective action against the impairment of striatal responses evoked by NaCN (electron transport inhibitor at site 3) and oligomycin (inhibitor of mitochondrial ATP synthesis), but idebenone at 10(-6) M did not. In light of these observations, the possibility that WEB 1881 FU and idebenone exert neuroprotective actions against hypoglycemic/hypoxic brain injury by activating energy metabolism with different mechanisms from each other has to be considered.

Topics: Animals; Benzoquinones; Brain Diseases; Corpus Striatum; Cyanides; Dopamine; Hypoglycemia; Hypoxia; In Vitro Techniques; Male; Neurons; Oligomycins; Parasympatholytics; Potassium; Pyrrolidinones; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

Idebenone, 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone, at a dose of 100 mg/kg (i.p.) markedly increased the level of 5-hydroxyindole-3-acetic acid (5-HIAA) in several brain regions without affecting monoamine contents in normal rats. In rats with cerebral ischemia, idebenone (10 mg/kg, i.p.) normalized the decreased levels of 5-HIAA in the cerebral cortex, hippocampus, diencephalon and brain stem. A 5-hydroxytryptamine (serotonin, 5-HT) biosynthesis inhibitor, DL-p-chlorophenylalanine (PCPA, 150 mg/kg, i.p.) decreased the levels of 5-HT to one-third of the control level 24 h after administration. Idebenone (10, 30, or 100 mg/kg, i.p.), administered 24 h after the treatment with PCPA, accelerated the PCPA-induced 5-HT decreased in the hippocampus, diencephalon and brain stem in a dose-dependent manner. Idebenone (100 mg/kg, i.p.) stimulated the release of 5-HT in the dorsal hippocampus as determined by in vivo differential pulse voltammetry. Idebenone, like p-chloroamphetamine (PCA), stimulated 5-HT release from slices of hippocampus and diencephalon, and the formation of cyclic AMP in a concentration-dependent manner in rat diencephalon slice. This stimulation was almost completely blocked by methysergide, a 5-HT receptor blocker. Idebenone slightly and PCA markedly inhibited 5-HT uptake into hippocampus slices. The mechanism of the 5-HT releasing actions of idebenone in the hippocampal slices may be mediated through endogenous calcium. These results suggest that idebenone has an enhancing effect on the turnover of 5-HT in the hippocampus, diencephalon, and brain stem of rats.

Topics: Animals; Benzoquinones; Biogenic Monoamines; Brain; Brain Ischemia; Cyclic AMP; Disease Models, Animal; Fenclonine; Hippocampus; Hydroxyindoleacetic Acid; Indoles; Male; Quinones; Rats; Rats, Inbred Strains; Serotonin; Ubiquinone

Monoamine metabolites and norepinephrine (NE) in the cerebrospinal fluid of patients with cerebrovascular dementia were measured to study the effects of administration of idebenone. Six patients with cerebral infarction and one with cerebral hemorrhage (mean age 65.4 years) were enrolled as subjects. All the patients had mental and intelligence impairment which was evaluated by the Hasegawa's Dementia Rating (DR) Scale. The patients were medicated with a 90 mg/day dose of idebenone for 1 to 2 months, and homovanillic acid (HVA), 5-hydroxyindole acetic acid (5-HIAA), 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) and NE in the cerebrospinal fluid were determined by high-performance liquid chromatography before and after the medication of idebenone. Before the medication, the level of HVA was 21.7 +/- 1.4 ng/ml (mean +/- SE), which was significantly lower (p less than 0.01) as compared with that in control subjects of similar age. The level of 5-HIAA was 18.5 +/- 2.7 ng/ml, and that of MHPG 9.5 +/- 0.7 ng/ml, both of which were lower than those of the controls, though statistically not significant. NE was similar to the control value. After administration of idebenone, HVA measured was 27.1 +/- 3.2 ng/ml, showing a tendency to increase. The levels of 5-HIAA and MHPG were 26.7 +/- 2.3 ng/ml and 10.7 +/- 0.6 ng/ml, respectively, which were significantly (p less than 0.05) higher than the premedication values. The percentages of the change were 12.8 +/- 8.0 for HVA, 58.2 +/- 18.5 for 5-HIAA and 14.2 +/- 5.0 for MHPG. The score of the DR scale was improved by 5 or less after the idebenone medication in most subjects. HVA and 5-HIAA increased markedly in the patients who showed a tendency of improvement of mental impairment as evaluated by the DR scale. The results suggested that idebenone would improve abnormalities in neurotransmitters of patients with cerebrovascular dementia, especially promoting serotonin turnover.

Topics: Aged; Aged, 80 and over; Benzoquinones; Biogenic Monoamines; Dementia, Vascular; Homovanillic Acid; Humans; Hydroxyindoleacetic Acid; Male; Methoxyhydroxyphenylglycol; Middle Aged; Quinones; Ubiquinone

The inhibitory effect of 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone) on platelet aggregation was studied in rat and human platelets in vitro, and the mechanism of inhibition was examined in rat platelets. Idebenone inhibited the aggregation induced by collagen and thrombin in washed platelets, and by arachidonate and ADP in platelet-rich plasma (PRP). The inhibition was more prominent in collagen- and arachidonate-induced aggregation. In collagen-induced aggregation of human platelets, idebenone was 8-fold more potent than aspirin. In addition, idebenone inhibited prostaglandin synthesis and thromboxane B2 production, and also increased the cyclic AMP content in platelets. However, the concentration of idebenone required to inhibit thromboxane B2 production was much lower than that required to increase cyclic AMP. These results indicate that idebenone inhibits platelet aggregation by inhibiting thromboxane B2 synthesis rather than by increasing cyclic AMP content.

Topics: Benzoquinones; Blood Platelets; Cyclic AMP; Humans; Lipid Peroxidation; Male; Platelet Aggregation; Platelet Aggregation Inhibitors; Prostaglandins; Quinones; Thromboxane B2; Ubiquinone

The effects of idebenone and vinpocetine which reportedly prevent impairment of learning and memory were studied in vitro, on the long-term potentiation of the population spike in the pyramidal layer of CA3 region of slices of hippocampus in the guinea pig. Idebenone (10(-9) M-10(-6) M) or vinpocetine (10(-7) M-10(-6) M) significantly augmented long-term potentiation in the mossy fibre-CA3 pyramidal cell system, without any significant changes in population spikes in the absence of tetanic stimulation. These results suggest that both drugs have direct actions on the hippocampal neurones to augment long-term potentiation at fairly small concentrations. Further, when the two drugs were applied together, the augmenting effects were additive.

Topics: 2-Amino-5-phosphonovalerate; Animals; Anticonvulsants; Benzoquinones; Electric Stimulation; Guinea Pigs; Hippocampus; In Vitro Techniques; Male; Pyramidal Tracts; Quinones; Receptors, N-Methyl-D-Aspartate; Receptors, Neurotransmitter; Time Factors; Ubiquinone; Valine; Vinca Alkaloids

The ameliorating effects of idebenone and indeloxazine hydrochloride on the impairment of memory and learning were studied in cerebral embolized rats. The embolized rats had impaired memory and learning ability in the radial maze task; these were demonstrated by a decrease in correct responses and an increase in total errors. In particular, the rats showed severe impairment of working memory, as shown by a marked increase in the numbers of re-entries into the arm that had been already visited. Idebenone (30 mg/kg, p.o.) exerted marked ameliorating effects on the impairment in the embolized rats: the drug significantly increased the correct responses and decreased the errors. Indeloxazine hydrochloride also improved the memory impairment in the embolized rats, as shown by a reduction of the errors. The ameliorating effects of these drugs may be due mainly to improvement of hypofunctions of the central nervous system. These results confirm that idebenone and indeloxazine hydrochloride may have ameliorating actions on impairment of memory and learning induced by brain hypofunction, and they suggest that the action of idebenone is more potent than that of indeloxazine hydrochloride.

Topics: Animals; Antidepressive Agents; Benzoquinones; Intracranial Embolism and Thrombosis; Learning Disabilities; Male; Memory Disorders; Morpholines; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

Two patients with mitochondrial myopathy, encephalopathy, lactic acidosis and strokelike episodes (MELAS) in one family are reported. Pathological examination of case 1 showed ragged-red fibers, with 7% of the fibers being unstained by cytochrome c oxidase stain, peripheral nerve damage, multiple areas of softening in the cerebrum and midbrain, and spongy changes in the cerebrum, optic nerve and pons. Electron microscopic examination revealed abnormal accumulations of mitochondria in the skeletal muscle, smooth muscle and cardiac muscle. The activity of cytochrome c oxidase in the brain and liver showed a tendency to decrease. In case 2 (maternal aunt of case 1), muscular weakness and peripheral nerve damage improved by treatment with coenzyme Q10. By adding idebenone to the coenzyme Q10 therapy, the EEG and Wechsler's Adult Intelligence Scale (WAIS) improved. Furthermore, in the cerebral spinal fluid (CSF), the protein, lactate, and pyruvate decreased, and the monoamines and monoamine metabolites increased.

Topics: Acidosis, Lactic; Adolescent; Benzoquinones; Brain Diseases; Cerebrovascular Disorders; Female; Humans; Male; Middle Aged; Mitochondria, Muscle; Quinones; Syndrome; Ubiquinone

Improvement of energy metabolism in ischemic cerebral tissue benefits the therapy of occlusive cerebrovascular disorders. In the present study, the effects of 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone) on neurological signs, such as ischemic seizures, lactate and ATP contents of the cerebral cortex, and local cerebral blood flow, were assessed in stroke-prone spontaneously hypertensive rats (SHRSP) with experimentally induced cerebral ischemia. Experimental cerebral ischemia was caused by bilateral carotid artery occlusion (BCAO) in male SHRSP (8-10 weeks old). Pretreatment with idebenone (10-100 mg/kg, p.o.) for 3 or 10 days delayed the onset of ischemic seizure (acute stroke) and prolonged survival time in SHRSP roughly in a dose-dependent manner. When the compound (100 mg/kg, i.p.) was given once 30 min after BCAO, it exerted similar ameliorating effects on the neurological deficits. When idebenone (100 mg/kg for 3 days) was given orally, it did not significantly inhibit the decrease in regional cerebral blood flow induced by BCAO. However, the same treatment markedly inhibited increases in the lactate content and lactate/pyruvate ratio and the decrease in ATP content of the cerebral cortex. The compound did not affect cerebral blood flow in normal rats. These results suggest that idebenone ameliorates the neurological deficits related to cerebral ischemia, and that this effect is mediated by improving cerebral energy metabolism.

Topics: Animals; Benzoquinones; Brain; Brain Ischemia; Cerebrovascular Circulation; Disease Models, Animal; Energy Metabolism; Motor Activity; Papaverine; Quinones; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Ubiquinone

The effects of 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone) on neurological deficits following cerebrovascular lesions were examined in stroke-prone spontaneously hypertensive rats (SHRSP). The SHRSP were maintained on a 1% NaCl solution as drinking water to shorten the onset time of cerebrovascular lesions (stroke). After the onset of stroke, the salt solution was exchanged for tap water, and idebenone (30 and 100 mg/kg) was administered orally once daily for 3 weeks. The neurological deficits were evaluated by a specially designed scoring system or by an open-field test. Idebenone decreased the severity of the neurological deficits in a dose-dependent manner and this was statistically significant in the high-dose group. The severity of neurological changes was inversely related to the motor activity in the open-field test performed when the experiment was terminated, indicating the appropriateness of the scoring system. Moreover, the compound (100 mg/kg) significantly ameliorated a decrease in food intake (anorexia) that followed the onset of stroke. These results suggest that idebenone may be useful to treat patients with cerebrovascular lesions.

Topics: Animals; Benzoquinones; Body Weight; Brain; Cerebrovascular Disorders; Dose-Response Relationship, Drug; Eating; Male; Motor Activity; Quinones; Rats; Rats, Inbred SHR; Ubiquinone

The effects of idebenone, a cerebral metabolic enhancer, on learning and memory impairment in two rat models with central cholinergic or serotonergic dysfunction were investigated using positively reinforced learning tasks. A delayed alternation task using a T maze was employed to test the effect of idebenone on short-term memory impairment induced by a cholinergic antagonist, scopolamine. A correct response, defined as a turn toward the arm opposite to that in the forced run, was rewarded with food pellets. Scopolamine (0.2 and 0.5 mg/kg, i.p.) significantly decreased the correct responses to the chance level in the 60-s-delayed alternation task. The scopolamine (0.2 mg/kg, i.p.)-induced impairment of short-term memory was improved by idebenone (3-30 mg/kg, i.p.) or an acetylcholinesterase inhibitor, physostigmine (0.1 and 0.2 mg/kg, i.p.), administered simultaneously. The central serotonergic dysfunction model was produced by giving rats a diet deficient in tryptophan, a precursor of serotonin. The rats fed on a tryptophan-deficient diet (TDD) showed a slower learning process in the operant brightness discrimination task (mult V115 EXT) than did rats fed on a normal diet. Idebenone (60 mg/kg/day) admixed with the TDD decreased the number of lever-pressing responses emitted during the extinction periods. The percentage of correct responses was significantly higher in the idebenone-treated group than in the control TDD group. These results suggest that idebenone may improve both the impairment of short-term memory induced by a decreased cholinergic activity and the retardation of discrimination learning induced by central serotonergic dysfunction.

Topics: Acetylcholine; Animals; Benzoquinones; Cerebral Cortex; Cerebrovascular Disorders; Discrimination Learning; Learning Disabilities; Male; Memory Disorders; Memory, Short-Term; Quinones; Rats; Rats, Inbred Strains; Scopolamine; Serotonin; Ubiquinone

Two rat models of memory impairment in passive avoidance learning induced by cerebrovascular disturbance, were established to estimate the effects of a cerebral metabolic enhancer, idebenone. Transient and global cerebral ischemia in rats, produced by 4-vessel occlusion for 200 s immediately after the acquisition trial of passive avoidance learning, shortened the latencies in the retention test trial performed 24 h later. This retrograde amnesia was reversed significantly by idebenone administered orally or intraperitoneally at the doses of 10 and 30 mg/kg before the retention test trial. Idebenone at a dose of 10 mg/kg, given intraperitoneally before or immediately after the ischemia, also markedly inhibited the appearance of amnesia. In the second model, permanent and cerebral hemisphere embolization produced by injecting 2,000 microspheres into the internal carotid artery, significantly impaired passive avoidance learning performed 7 days later. The repeated administration of idebenone (30 mg/kg, i.p.). once a day after the embolization, significantly improved the impairment of passive avoidance learning in the embolized rats. Furthermore, physostigmine and arginine-vasopressin as reference compounds improved the impairment of passive avoidance learning in these models. These findings suggest that idebenone ameliorates memory impairment induced by cerebral vascular disturbance in rats.

Topics: Administration, Oral; Animals; Avoidance Learning; Benzoquinones; Brain Ischemia; Cerebrovascular Disorders; Injections, Intraperitoneal; Intracranial Embolism and Thrombosis; Male; Memory Disorders; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

The effects of idebenone on survival time of mice subjected to hypoxia induced by N2 and CO2 inhalation and KCN injection were studied. Idebenone (10, 20, 50 and 100 mg/kg, i.p.) prolonged the survival time of mice exposed to a hypoxic condition (98% N2, 2% O2) in a dose-dependent manner: significant prolongations were observed at doses higher than 20 mg/kg. The drug also exerted a similar elongation effect at the same doses under conditions of 100% CO2 gas inhalation and KCN injection (3 mg/kg, i.v.). The results suggest that idebenone protects against hypoxia by improving cerebral energy metabolism.

Topics: Animals; Benzoquinones; Cerebral Cortex; Energy Metabolism; Hypoxia; Mice; Mice, Inbred ICR; Quinones; Ubiquinone

Cerebral ischemia was induced by a 200-s occlusion of both common carotid arteries in rats in which both vertebral arteries had been permanently cauterized. In the ischemic rats, a significant decrease in acetylcholine (ACh) and a marked increase in choline were observed in the cerebral cortex, hippocampus, striatum, and diencephalon. A slight increase in choline was also observed in the cerebellum and brain stem. Pretreatment with idebenone (10 mg/kg, i.p.) inhibited the decrease in ACh and the increase in choline in the forebrain regions. In addition, the same dose of idebenone inhibited the increments of lactate and free fatty acid contents and tended to inhibit the decrement of the ATP content in the cerebral cortex of the cerebral ischemic rats. These results indicate that idebenone inhibits the alteration of the ACh level and the disruption of membrane phospholipids in the brain of ischemic rats; these effects may be mediated by improved cerebral energy metabolism.

Topics: Acetylcholine; Animals; Benzoquinones; Brain; Brain Ischemia; Choline; Disease Models, Animal; Energy Metabolism; Fatty Acids, Nonesterified; Male; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

To investigate the possible action sites of a cerebral metabolism activator, idebenone, (6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone), its distribution in the brain and effect on local cerebral glucose utilization (LCGU) were studied in normal (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP) with cerebrovascular lesions. 14C-Idebenone distributed rapidly into the brain after intravenous administration (10 mg/kg), and the total 14C contents in the brain at peak time corresponded to 0.45-0.56% of the dosages. An autoradiographic study showed that the 14C levels were higher in the white than in the gray matter. When 14C-idebenone was administered orally (100 mg/kg) and intraperitoneally (30 mg/kg), the total 14C levels were not markedly different among the brain regions of the rats. The concentration of unchanged idebenone was higher in the cerebral cortex, thalamus, and cerebellum than that in the other brain regions. Studies on LCGU demonstrated that idebenone (30 mg/kg/day, i.p., for 3 days) improved the reduction of LCGU in SHRSP with stroke, especially in the temporal cortex, thalamus dorsomedial nucleus, subthalamic nucleus, mamillary body, hippocampus dentate gyrus, caudate-putamen, inferior colliculus, and cerebellar nucleus. Based on these results, possible action sites of idebenone for its main pharmacologic effects are discussed.

Topics: Animals; Benzoquinones; Brain; Cerebrovascular Disorders; Glucose; Male; Quinones; Rats; Rats, Inbred SHR; Rats, Inbred Strains; Rats, Inbred WKY; Ubiquinone

Lipid peroxidation in brain mitochondria was induced by NADH in the presence of ADP and FeCl3. A novel quinone compound, idebenone, inhibited this peroxidation and the inhibition was markedly enhanced by succinate, a substrate of mitochondrial respiration. The concentration of succinate required to exert the maximal effect was 1.5 mM. The concentration of idebenone giving 50% inhibition (IC50) was 0.5 and 84 microM in the presence and absence of succinate, respectively, indicating that succinate enhances the inhibition by 170-fold. Moreover, the inhibitory effect of idebenone in the presence of succinate was abolished by adding thenoyltrifluoroacetate (TTFA), an inhibitor of complex II in the mitochondrial respiratory chain. These results indicate that idebenone is changed through complex II to its reduced form, which protects mitochondria against lipid peroxidation.

Topics: Animals; Benzoquinones; Brain; Lipid Peroxidation; Mitochondria; Quinones; Rats; Succinates; Ubiquinone

Stroke-prone spontaneously hypertensive rats (SHRSP) were kept on a 1% NaCl solution as drinking water to shorten the onset-time of a stroke. The level of lipoperoxide (LPO) in the erythrocytes of SHRSP loaded with salt for 22 days was significantly higher than that of the controls. Idebenone treatment (30 mg/kg per day, p.o.) markedly decreased the LPO to the level of the controls. Hemolysis in SHRSP was accelerated by the salt-loading. Idebenone significantly inhibited the hemolysis in a dose-dependent manner. These results suggest that idebenone inhibits lipid peroxidation in erythrocytes and stabilizes the erythrocyte membrane.

Topics: Animals; Benzoquinones; Cerebrovascular Disorders; Erythrocytes; Hemolysis; Hypertension; Lipid Peroxidation; Male; Quinones; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Ubiquinone

The oxidation of succinate and NADH in a ubiquinone-depleted canine brain mitochondrial preparation was restored by a low molecular weight benzoquinone, idebenone. Idebenone inhibited NADH(NADPH)/ADP-Fe3+-dependent lipid peroxidation in canine brain mitochondria and protected against the resulting inactivation of NADH-cytochrome c reductase activity. Idebenone did not affect the activities of succinate oxidase in canine and rat brain mitochondria but suppressed the oxygen consumption in NADH oxidation. This suppression might be related to the inhibition of lipid peroxidation. These results suggest that idebenone functions as an electron carrier in the respiratory chains of brain mitochondria and as an antioxidant against membrane damage caused by lipid peroxidation in brain mitochondria.

Topics: Animals; Benzoquinones; Brain; Cell Membrane; Dogs; Female; Lipid Peroxidation; Male; Microsomes; Mitochondria; Oxygen Consumption; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

A daily dose of 90 mg of idebenone was given to nine patients with cerebrovascular disorders to investigate its effects on clinical symptoms and electroencephalograms (EEG). Changes in EEG before and after the administration were compared quantitatively by computer analysis using the wave-form recognition method. Significant increase in frequency in the alpha band (O1) and trends of increased appearance of beta waves, decreased appearance of alpha 1 bands, and lowered amplitude in the alpha 1 and alpha 2 bands were observed after administration of idebenone. The theta waves of 30 microV and over had a significantly diminished maximum amplitude (C3) and a tendency to appear less often. Mean frequency of the EEG and appearance of fast waves apparently increased in the patients showing improvement of the clinical symptoms as compared with those not showing improvement. The results suggested that idebenone improved the EEG in the patients with cerebrovascular disorders, causing changes in EEG similar to those observed with psychostimulants.

Topics: Adult; Aged; Aged, 80 and over; Benzoquinones; Cerebrovascular Disorders; Electroencephalography; Female; Humans; Male; Middle Aged; Quinones; Ubiquinone

The effects of reducing agents and antioxidants on L-Glutamate (Glu)-induced cytotoxicity were examined in the N18-RE-105 neuronal cell line. The cytotoxicity by Glu (1 and 10mM) was potentiated by exposure to growth medium containing a low concentration of cystine (5-100 microM), instead of the normal medium containing 200 microM cystine. In contrast, the toxicity was suppressed by increasing the cystine concentration to 500 to 1000 microM. Reducing agents, cysteine (30-1000 microM), dithiothreitol (10-250 microM) and glutathione (GSH, 10-1000 microM) also protected the cells against the cytotoxicity of 10 mM Glu in a concentration-dependent manner. The antioxidants vitamin E (10-100 microM), idebenone (0.1-3 microM) and vinpocetine (10-100 microM) also provided marked protection against the cytotoxicity of Glu (10 mM) or quisqualate (1 mM). Antioxidants also prevented the delayed cell death caused by lowering the concentration of cystine in the medium to 5 microM. Incubation of the cells with 10 mM Glu caused a marked decrease in cellular GSH levels. Although cysteine and dithiothreitol prevented the GSH reduction caused by Glu, antioxidants did not. The cellular levels of oxidants were assessed using 2,7-dichlorofluorescin, a probe that accumulates within cells and is converted to a fluorescent product by oxidation. Glu (10 mM) caused a marked increase in such fluorescence, whereas vitamin E and idebenone reduced markedly the number of fluorescent cells to control levels even added with 10 mM Glu. These results indicate that oxidative stress due to loss of cellular levels of GSH is one mechanism whereby Glu/quisqualate exert cytotoxicity and suggest that centrally active antioxidants may reduce neuronal damage in pathologic conditions associated with excessive Glu release.

Topics: Animals; Antioxidants; Benzoquinones; Cell Survival; Cystine; Excitatory Amino Acid Antagonists; Glutamates; Glutathione; Mice; Peroxides; Quinones; Rats; Sulfhydryl Compounds; Time Factors; Tumor Cells, Cultured; Ubiquinone; Vitamin E

A rise in blood and liver acetaldehyde concentrations following an intragastric administration of ethanol to rats was significantly inhibited when the quinone derivatives 2,3-dimethoxy-5-methyl-6-decaprenyl-1,4-benzoquinone (ubidecarenone, coenzyme Q10), 4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-f]quinoline-2,7,9-tricarboxylic acid (pyrroloquinoline quinone, PQQ) and 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone) were injected intraperitoneally, prior to ethanol load, at a dose of 10, 11.5 and 30 mg/kg of body weight, respectively. When acetaldehyde was incubated in vitro with 1,4-benzoquinone (3.7-13.0 mM) or PQQ (1.4-4.9 mM) at 0 and 40 degrees C, the acetaldehyde concentrations slowly decreased with incubation time at 40 degrees C. The results suggest that low acetaldehyde concentrations following ethanol load are due to an accelerated oxidation of acetaldehyde by PQQ in the liver and the circulating blood.

Topics: Acetaldehyde; Animals; Benzoquinones; Coenzymes; Ethanol; In Vitro Techniques; Liver; Male; PQQ Cofactor; Quinolones; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

Effects of bifemelane hydrochloride, idebenone and indeloxazin hydrochloride on ischemia-induced decrease in acetylcholine (ACh) levels were studied in gerbils. Among these three drugs, only bifemelane hydrochloride significantly inhibited the decrease in ACh concentration in the cerebral cortex, hippocampus and striatum of ischemic gerbils. This suggests that bifemelane hydrochloride has an anti-ischemic action and beneficial effects on various symptoms induced by ischemia.

Topics: Acetylcholine; Animals; Benzhydryl Compounds; Benzoquinones; Brain Chemistry; Brain Ischemia; Cerebral Cortex; Corpus Striatum; Gerbillinae; Hippocampus; Humans; Infant, Newborn; Morpholines; Quinones; Ubiquinone

Topics: Animals; Benzoquinones; Cattle; Female; In Vitro Techniques; Liver; Mitochondria, Heart; Quinones; Rabbits; Rats; Rats, Inbred Strains; Ubiquinone

Topics: Acidosis, Lactic; Benzoquinones; Brain Diseases, Metabolic; Coenzymes; Female; Humans; Middle Aged; Mitochondria, Muscle; Neuromuscular Diseases; Quinones; Syndrome; Ubiquinone

The effects of idebenone and various nootropic drugs on lipid peroxidation in rat brain homogenate were examined. Idebenone inhibited lipoperoxide (LPO) production in brain homogenate in a concentration-dependent manner, with an IC50 of 38 microM. The inhibition was strongly enhanced (about 100-fold) by adding succinate, a substrate in the mitochondrial respiration. The optimal concentration of succinate was 0.5 mM. Inhibition of lipid peroxidation in brain homogenate by various nootropic drugs in the presence or absence of succinate was then examined. Drugs added to the brain homogenate at 100 microM in the absence of succinate inhibited LPO production in the order: idebenone greater than vinpocetine greater than bifemelane greater than indeloxazine greater than calcium hopantenate. However, when the drugs were added at 1 microM in the presence of succinate, only idebenone demonstrated inhibition. These results suggest that although almost all of the drugs tested inhibit lipid peroxidation in brain homogenate, only idebenone is activated by succinate, the other drugs being insensitive to this compound.

Topics: Animals; Benzhydryl Compounds; Benzoquinones; Brain; Depression, Chemical; Dose-Response Relationship, Drug; gamma-Aminobutyric Acid; In Vitro Techniques; Lipid Peroxides; Male; Morpholines; Pantothenic Acid; Quinones; Rats; Rats, Inbred Strains; Succinates; Ubiquinone; Vinca Alkaloids

The effects of idebenone, a cerebral metabolism activator, on mouse-killing behavior (muricide) in rats with lesions of the midbrain raphe nuclei were studied. Single administration of idebenone (30 and 100 mg/kg, IP) inhibited the muricidal behavior in the raphe-lesioned rats in a dose-dependent manner. Idebenone also suppressed muricide in the olfactory bulbectomized rats, although the effect was less marked than that shown in the raphe-lesioned rats. In addition, the antimuricidal effect of idebenone was augmented with repeated administration. These results support previous findings that idebenone has an activating action on central serotonergic neurons in rats and in patients with cerebrovascular dementia, and suggest that idebenone may improve some of the depressive symptoms often observed in patients with cerebrovascular lesions and other forms of brain disturbance.

Topics: Aggression; Animals; Behavior, Animal; Benzoquinones; Imipramine; Male; Olfactory Bulb; Quinones; Raphe Nuclei; Rats; Rats, Inbred Strains; Ubiquinone

Elucidation of the alterations of intracerebral neurotransmitters in cerebrovascular dementia is of prime importance not only in revealing patho-physiological mechanism but also in developing the therapy for the disease. We measured monoamine metabolites and norepinephrine (NE) in cerebrospinal fluid of patients with cerebrovascular dementia, to study the effects of administration of 6-(10-hydroxydecyl)-2, 3-dimethoxy-5-metyl-1,4-benzoquinone (idebenone, CV-2619). Six patients with cerebral infarction and 1 with cerebral hemorrhage, at the mean age of 65.4 years, were enrolled as subjects. All patients had mental and intelligent impairment, and the Hasegawa's Dementia Rating (DR) Scale was performed. The patients were medicated with 90 mg daily dose of CV-2619 for 1 to 2 months, and homovanillic acid (HVA), 5-hydroxyindole acetic acid (5-HIAA), 3-methoxy-4-hydroxyphenylethylenglycol (MHPG), NE in cerebrospinal fluid were determined by high-performance liquid chromatography before and also after the medication. Before the medication, HVA was 21.7 +/- 1.4 ng/ml (mean +/- SE), which was significantly low (p less than 0.01), compared with controls at a similar age: 5-HIAA was 18.5 +/- 2.7 ng/ml, and MHPG, 9.5 +/- 0.7 ng/ml, both of which were not significantly low, but tended to be low, compared with the controls. NE was similar to the control value. With the administration of CV-2619, HVA measured 27.1 +/- 3.2 ng/ml, showing a tendency to increase; 5-HIAA was 26.7 +/- 2.3 ng/ml, and MHPG, 10.7 +/- 0.6 ng/ml, both of which increased significantly (p less than 0.05), compared with the respective premedication values.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aged; Benzoquinones; Biogenic Amines; Cerebrovascular Disorders; Chromatography, High Pressure Liquid; Dementia; Homovanillic Acid; Humans; Hydroxyindoleacetic Acid; Methoxyhydroxyphenylglycol; Middle Aged; Norepinephrine; Quinones; Ubiquinone

Topics: Animals; Benzoquinones; Female; In Vitro Techniques; Lipid Peroxides; Microsomes, Liver; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

To investigate the possible action-sites of a cerebral metabolism activator, idebenone (CV-2619), its distribution in the brain and effect on local cerebral glucose utilization (LCGU) were studied both in normal rats (WKY) and in stroke-prone spontaneously hypertensive rats (SHRSP) with cerebrovascular lesions. At 5 min after intravenous administration of [14C] CV-2619 (10 mg/kg), the distribution ratio in the brain was 0.45-0.56% of the dosage. Autoradiographic study showed that 14C levels were higher in the white matter than in the grey matter. When [14C] CV-2619 was administered orally (100 mg/kg) and intraperitoneally (30 mg/kg), 14C levels in eleven brain regions (15 min after administration) were 0.22-0.39 microgram/g (CV-2619 equivalent) and 1.11-1.30 micrograms/g, respectively, in WKY and 0.17-0.28 microgram/g and 1.66-1.87 microgram/g, respectively, in SHRSP. Total 14C levels were not markedly different among the brain regions of the rats. The analysis of unchanged CV-2619 and its metabolites revealed that unchanged CV-2619 in the cerebral cortex, thalamus and cerebellum was relatively higher than that in the other brain regions. Studies on LCGU demonstrated that CV-2619 (30 mg/kg/day, i.p., for 3 days) improved the decrement of LCGU in the temporal cortex, thalamus dorsomedial nucleus, subthalamic nucleus, mamillary body, hippocampus dentate gyrus, caudate-putamen, inferior colliculus and cerebellar nucleus of SHRSP with stroke. Based on these results, the possible action-sites of CV-2619 for its main pharmacological effects were discussed.

Topics: Administration, Oral; Animals; Benzoquinones; Brain; Cerebrovascular Disorders; Glucose; Injections, Intravenous; Male; Quinones; Rats; Rats, Inbred SHR; Rats, Inbred Strains; Rats, Inbred WKY; Ubiquinone

The effects of 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone, CV-2619) on the contents, turnover, release and uptake of monoamines, especially serotonin (5-HT), in various brain regions of Wistar rats were studied in vivo and in vitro. In normal rats, an intraperitoneal (i.p.) dose of 100 mg/kg of CV-2619 had no significant effect on the levels of norepinephrine (NE), dopamine (DA) and their metabolites, and 5-HT in the brain regions examined, but it increased the levels of 5-hydroxyindole-3-acetic acid (5-HIAA), the main metabolite of 5-HT, in many brain regions. In rats with cerebral ischemia, a low dose (10 mg/kg, i.p.) of CV-2619 normalized the decreased levels of 5-HIAA in the cerebral cortex, hippocampus, diencephalon and brain stem. A 5-HT biosynthesis inhibitor, DL-p-chlorophenylalanine (PCPA, 150 mg/kg, i.p.), decreased the levels of 5-HT in all brain regions to one-third of the control levels 24 hr after administration in normal rats. CV-2619 (10, 30 or 100 mg/kg, i.p.), administered 24 hr after the treatment with PCPA, accelerated the PCPA-induced 5-HT decreases in the hippocampus, diencephalon and brain stem in a dose-dependent manner. In vitro CV-2619, like p-chloroamphetamine (PCA), stimulated 5-HT release from slices of the hippocampus and diencephalon. CV-2619 slightly inhibited and PCA markedly inhibited 5-HT uptake into hippocampal slices. The mechanism of the 5-HT releasing action of CV-2619 in hippocampal slices seems to be mediated through endogenous calcium. These results suggest that CV-2619 has an enhancing effect on the turnover of 5-HT in the hippocampus, diencephalon and brain stem of rats.

Topics: 3,4-Dihydroxyphenylacetic Acid; Animals; Benzoquinones; Biogenic Amines; Brain; Brain Ischemia; Chromatography, High Pressure Liquid; Dopamine; Dose-Response Relationship, Drug; Egtazic Acid; Fenclonine; Hippocampus; Homovanillic Acid; Hydroxyindoleacetic Acid; Male; Methoxyhydroxyphenylglycol; Norepinephrine; Quinones; Rats; Rats, Inbred Strains; Serotonin; Time Factors; Ubiquinone

The effects of idebenone (CV-2619) and its metabolites on respiratory activity and lipid peroxidation in isolated brain mitochondria from rats and dogs were studied. CV-2619 was easily reduced by canine brain mitochondria in the presence of respiratory substrates. Reduced CV-2619 (2H-CV-2619) was rapidly oxidized through the cytochrome b chain, indicating that the compound functioned simply as an electron carrier of mitochondrial respiratory system. Both nicotinamide adenine dinucleotide (NADH)- and nicotinamide adenine dinucleotide phosphate (NADPH)-dependent lipid peroxidations were examined in canine brain mitochondria in the presence of adenosine diphosphate (ADP) and Fe3+. NADH-cytochrome c reductase activity was sensitive to NADPH-dependent lipid peroxidation. CV-2619 (10(-5)M) strongly inhibited both types of the lipid peroxidation reactions and protected the resultant inactivation of the NADH-cytochrome c reductase activity. Activities of succinate oxidase in rat and canine brain mitochondria were virtually unaffected by CV-2619 and its metabolites (10(-5)-10(-6) M). On the other hand, CV-2619 markedly suppressed the state 3 respiration in glutamate oxidation in a dose dependent manner without any effect on the state 4 respiration and the ADP/O ratio in intact rat brain mitochondria. The inhibitory effect of CV-2619 was also observed in NADH-cytochrome c reductase, but not in NADH-2,6-dichlorophenolindophenol (DCIP) and NADH-ubiquinone reductases in canine brain mitochondria. These facts and results of inhibitor analysis suggest that the action site of CV-2619 is NADH-linked complex I in the mitochondrial respiratory chain and is different from that of inhibitors of oxidative phosphorylation such as rotenone, oligomycin and 2,4-dinitrophenol. Finally, the above findings suggest that CV-2619 acts as an electron carrier in respiratory chains and functions as an antioxidant against membrane damage caused by lipid peroxidation in brain mitochondria. It appears likely that the inhibition of oxygen consumption caused by CV-2619 is related to the effect on non-respiratory systems such as lipid peroxidation which also consumes oxygen.

Topics: Animals; Benzoquinones; Brain Chemistry; Dogs; Female; gamma-Aminobutyric Acid; Glutamates; Glutamic Acid; In Vitro Techniques; Lipid Peroxides; Malates; Male; Mitochondria; NADP; Oxygen Consumption; Pantothenic Acid; Pyruvates; Pyruvic Acid; Quinones; Rats; Rats, Inbred Strains; Respiration; Species Specificity; Succinates; Ubiquinone

The addition of CV-2619 (10(-4) M) stimulated the release of endogenous 5-hydroxytryptamine (5-HT) markedly and that of norepinephrine (NE) slightly from slices of rat diencephalon, but it did not affect dopamine (DA) release. The addition of CV-2619 (10(-5)-10(-4) M) or 5-HT (10(-6)-10(-4) M) stimulated cyclic AMP formation in a concentration-dependent manner. Methysergide (10(-4) M), a 5-HT receptor blocker, almost completely blocked CV-2619 (10(-4) M)- and 5-HT (10(-4) M)-induced cyclic AMP formation. These results suggest that CV-2619 stimulates cyclic AMP formation via endogenous monoamine, particularly, 5-HT release.

Topics: Animals; Benzoquinones; Biogenic Amines; Cyclic AMP; Diencephalon; Dopamine; In Vitro Techniques; Male; Norepinephrine; Quinones; Rats; Rats, Inbred Strains; Serotonin; Theophylline; Ubiquinone

The effects of a novel compound, idebenone [6-(10-hydroxydecyl)-2, 3-dimethoxy-5-methyl-1, 4-benzoquinone] and cholinergic drug on short-term memory (STM) were studied in a delayed alternation task in rats. Rats were initially trained using a delayed alternation task in which a forced run to one arm of a T-maze was followed by a free-choice run. A correct free-choice response was defined as a turn toward the arm opposite to that in the forced run, and was rewarded with food pellets. When the time interval between the forced run and free-choice run was longer than 60 sec, the correct responses decreased by about 30% compared with that in no delay trials. After repeated training of the 60 sec-delayed alternation task, the effect of an anticholinergic drug scopolamine (0.1-0.5 mg/kg, ip) on the delayed alternation task was tested. The drug administered 20 min before the test significantly decreased the correct responses in a dose dependent manner. The effect of scopolamine (0.2 mg/kg, ip) was antagonized by the simultaneous administration of physostigmine (0.05-0.2 mg/kg, ip) in a dose dependent manner. Furthermore, physostigmine (0.1 and 0.2 mg/kg, ip) alone increased correct responses in the same task. Idebenone (3-30 mg/kg, ip), administered simultaneously with scopolamine, significantly improved the scopolamine-induced decrement of correct responses, with the highest efficacy at 10 mg/kg. The compound alone did not affect the number of correct responses. These results suggest that STM is closely related to the cholinergic system, and that idebenone may have an improving effect on the impairment of STM induced by a decreased cholinergic activity.

Topics: Animals; Benzoquinones; Brain; Cholinergic Fibers; Male; Memory Disorders; Memory, Short-Term; Physostigmine; Quinones; Rats; Rats, Inbred Strains; Scopolamine; Ubiquinone

The effect of idebenone (CV-2619), 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone, on 5-hydroxyindoles in the dorsal hippocampus of rats was investigated by using in vivo differential pulse voltammetry. CV-2619 (100 mg/kg, i.p.) produced a large increase in oxidation current at 280 mV (peak 2) in the dorsal hippocampus. The increase was statistically significant at 20 and 30 min after the administration. 5-Hydroxytryptophan (150 mg/kg, i.p.) also caused a marked increase in peak 2, which was clearly inhibited by the treatment with pargyline (50 mg/kg, i.p.). Thus, the increase in peak 2 induced by CV-2619 seems to be associated with an increase in the 5-HT metabolite 5-hydroxyindoleacetic acid and also partly with an increase in 5-HT.

Topics: 5-Hydroxytryptophan; Animals; Benzoquinones; Electrochemistry; Hippocampus; Indoles; Male; Pargyline; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

The effects of 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (CV-2619) on the respiration and non-respiratory oxygen consumption induced by ascorbate and Fe2+ in rat brain mitochondria were studied. When CV-2619 (100 and 300 mg/kg) was orally administered to rats for 3 days, it increased the state 3 respiration stimulated by ADP, slightly decreased the state 4 respiration after the consumption of ADP and resulted in a significant increase of the respiratory control index (RCI) by 14-19% for glutamate oxidation (p less than 0.01) and 10-17% for succinate oxidation (p less than 0.05), respectively. The RCI increasing effect of CV-2619 was dose dependent, but the compound had no effect on the ADP/O ratio. CV-2619 significantly suppressed by about 10% the non-respiratory oxygen consumption (p less than 0.02), which closely associated with non-enzymatic reactions such as lipid peroxidation, membrane lysis and swelling of mitochondria. Thus, CV-2619 may contribute to stimulate the net ATP formation by the well-coupling of electron and energy transfer, and by the reduction of non-respiratory oxygen consumption in cerebral metabolism.

Topics: Adenosine Diphosphate; Animals; Benzoquinones; Brain; In Vitro Techniques; Mitochondria; Oxygen Consumption; Phosphorylation; Quinones; Rats; Ubiquinone

Effect of idebenone (CV-2619) on memory impairment was studied in rats with cerebral embolization. The cerebral embolization, produced by injecting 2000 microspheres into the internal carotid artery, caused a significant impairment in passive avoidance response. Repeated administrations of idebenone (30 mg/kg/day, i.p.), partially but significantly improved the impairment of the passive avoidance response in the embolized rats. The results suggest that the repeated administration of idebenone exerts an ameliorating effect on memory impairment induced by cerebral embolization.

Topics: Animals; Arecoline; Arginine Vasopressin; Avoidance Learning; Benzoquinones; Intracranial Embolism and Thrombosis; Male; Memory; Physostigmine; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

Metabolic studies of idebenone (CV-2619), a new cerebral metabolism improving agent, in the rat and dog by thin-layer chromatography, gas-liquid chromatography-mass spectrometry and fast atom bombardment-mass spectrometry led to characterization of the following metabolites: the parent compound, 6-(9-carboxynonyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (QS-10), 6-(7-carboxyheptyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (QS-8), 6-(5-carboxypentyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (QS-6), 6-(3-carboxypropyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (QS-4), 1- or 4-phenyl sulfate of the hydroquinone derivatives of CV-2619 and QS-4, and 1- and 4-phenyl glucuronides of the hydroquinone derivative of QS-10. These results indicated that CV-2619 was metabolized by oxidation of the side chain followed by beta-oxidation to form successively QS-10, QS-8, QS-6 and QS-4, and reduction of the quinone ring and subsequent conjugation yielding the sulfates and glucuronides of the hydroquinone derivatives of CV-2619, QS-10, QS-8, QS-6 and QS-4.

Topics: Animals; Benzoquinones; Bile; Biotransformation; Chromatography, Gas; Chromatography, Thin Layer; Dogs; Glucuronates; Kinetics; Male; Mass Spectrometry; Quinones; Rats; Rats, Inbred Strains; Species Specificity; Ubiquinone

After oral administration of 14C-labeled idebenone (14C-CV-2619) to rats, the plasma 14C level reached a plateau at 15 min, which persisted till 8 h and then decreased with a half-life of 4.5 h. In dogs, after oral dosing, the plasma 14C peaked at 15 min, followed by biophysical decline with half-lives of 2.2 and 15.4 h. The plasma of both animals contained mostly metabolites, with a small amount of unchanged CV-2619, which was greater than 90% protein-bound. In rats given 14C-CV-2619 orally or intravenously, 14C was distributed widely in tissues, with relatively high concns. in the gut, liver and kidney. CV-2619 readily entered the rat brain to undergo subcellular distribution with a significant amount localized in mitochondria. The concn. of 14C in rat fetus was low, as was that in the milk. Oral 14C-CV-2619 was eliminated by rats and dogs mostly as metabolites within 48 h. In rats, more was excreted in urine than in feces, whereas in dogs excretion by these two routes was almost equal. Enterohepatic cycling of biliary 14C occurred in rats. Repeated oral ingestions of 14C-CV-2619 to rats resulted in no accumulation of 14C. The metabolites found in rats and dogs were QS-10, QS-8, QS-6 and QS-4 formed by oxidative shortening of the side chain of CV-2619, and desmethylated CV-2619 and QS-4. Glucuronides and sulfates of the dihydro (quinol) derivatives of the above metabolites were also detected. Dihydro QS-4 sulfate was the major metabolite in plasma and urine of both animals, while dihydro QS-10 glucuronide was predominant in rat bile.

Topics: Animals; Autoradiography; Benzoquinones; Blood Proteins; Brain; Chromatography, Thin Layer; Dogs; Erythrocytes; Feces; Female; Intestinal Absorption; Male; Placenta; Pregnancy; Protein Binding; Quinones; Rats; Rats, Inbred Strains; Species Specificity; Subcellular Fractions; Tissue Distribution; Ubiquinone

The effect of 6-(10-hydroxydecyl)-2, 3-dimethoxy-5-methyl-1, 4-benzoquinone (idebenone, CV-2619) on brightness discrimination learning of the operant type was examined in rats with central serotonergic dysfunction. The animal model was produced by feeding Wistar rats a diet deficient in tryptophan (a precursor of serotonin) as the control group. The control rats with central serotonergic dysfunction showed lower ability to learn the discrimination task (multiple VI 15 seconds extinction schedule) than normal feeding rats. Rats which were chronically administered with idebenone (60 mg/kg/day) admixed with the tryptophan deficient diet were used as an experimental group. In the control and experimental groups, total responses (R+ + R-) were significantly increased in the early stage of learning test period, compared with the normal rats. In the late stage of the learning periods, the numbers of R-decreased in idebenone-treated group but not in control group. Therefore, the correct response ratio [( R+/(R+ + R-)] X 100) was significantly higher in the treated group than in the control. The results suggest that idebenone, which has an improving action on cerebral energy metabolism and a stimulating action on central serotonergic turnover, may exert an ameliorating effect on impaired discrimination learning in rats with central serotonergic dysfunction.

Topics: Animals; Benzoquinones; Brain Diseases; Conditioning, Operant; Discrimination Learning; Learning Disabilities; Male; Quinones; Rats; Rats, Inbred Strains; Serotonin; Tryptophan; Ubiquinone; Visual Perception

Ten healthy male volunteers participated in this Phase I multiple dose study with CV-2619 (6-[10-hydroxydecyl]-2,3- dimethoxy-5-methyl-1,4-benzoquinone, idebenone). Each volunteer received single oral doses of 100 mg CV-2619 on study days 1 and 35, and during days 2 to 34, 300 mg daily in three divided doses. Blood and urine samples were collected for pharmacokinetic analysis of CV-2619 and its two major metabolites. CV-2619 was well tolerated with regard to the subjective and objective assessments made during the study. There were no changes in clinical laboratory values which could be directly attributed to the administration of CV-2619. The elimination of CV-2619 appeared to be biphasic with a mean terminal elimination half-life of 18 h. Levels of metabolites in serum were too low to provide adequate description of their elimination kinetics. CV-2619 and its metabolites showed no tendency to accumulate over the 35-day period.

Topics: Administration, Oral; Adult; Benzoquinones; Biotransformation; Drug Administration Schedule; Drug Evaluation; Drug Tolerance; Half-Life; Humans; Kinetics; Male; Quinones; Ubiquinone

Improvement of energy metabolism in ischemic cerebral tissue benefits the therapy of occlusive cerebrovascular lesions. In the present study, the effects of 6-(10-hydroxydecyl)-2, 3-dimethoxy-5-methyl-1, 4-benzoquinone (idebenone, CV-2619) on neurological signs, local cerebral blood flow, and cerebral energy metabolism were assessed in stroke-prone spontaneously hypertensive rats (SHRSP) with bilateral carotid artery occlusion (BCAO). Pretreatment with CV-2619 (10-100 mg/kg, p.o.) for three or ten successive days delayed the onset of ischemic seizure (acute stroke) and prolonged survival time in the SHRSP. When the compound (100 mg/kg, i.p.) was given once 30 min after BCAO, it exerted similar ameliorating effects on the neurological deficits. When CV-2619 (100 mg/kg for 3 days) was given orally, it did not inhibit a decrease in regional cerebral blood flow induced by the carotid artery occlusion. However, the same treatment markedly inhibited increases in lactate content and lactate/pyruvate ratio and a decrease in ATP content in the cerebral cortex. In addition, the compound showed no effect on cerebral blood flow in normal rats. These results suggest that CV-2619 has an ameliorating effect on neurological deficits related with cerebral ischemia, and this effect is mediated by improved cerebral energy metabolism.

Topics: Adenosine Triphosphate; Animals; Benzoquinones; Brain Ischemia; Cerebral Cortex; Cerebrovascular Circulation; Energy Metabolism; Lactates; Lactic Acid; Male; Quinones; Rats; Seizures; Ubiquinone

The effects of CV-2619 on the half-life and hemolysis of red blood cells (RBC) in stroke-prone spontaneously hypertensive rats (SHRSP) were examined. The half-life of RBC in SHRSP was shorter than that in control Wistar Kyoto rats (WKY) and was significantly prolonged in SHRSP kept on a diet containing 0.1% (w/w) of CV-2619 (calculated at 71.0 mg/kg/day): 11.7 +/- 0.4 days in untreated SHRSP (n = 11); 13.8 +/- 0.1 days in treated SHRSP (n = 5, P less than 0.01); and 14.8 +/- 0.5 days in WKY (n = 6). The hemolysis of RBC in salt-loaded SHRSP was accelerated compared with that in WKY. In SHRSP given CV-2619 (20 or 70 mg/kg/day, p.o.) for 2 weeks, the hemolysis was significantly inhibited; the percent hemolysis was 43.9 +/- 0.9% (n = 10) in the control, 39.5 +/- 0.9% (n = 9, P less than 0.01) in the group given 20 mg/kg CV-2619, and 37.1 +/- 0.8% (n = 9, P less than 0.001) in the group given 70 mg/kg CV-2619. These results suggest that the stabilizing effect of CV-2619 on the membrane of RBC is involved in its therapeutic effects in cerebral vascular disorders.

Topics: Animals; Benzoquinones; Cerebrovascular Disorders; Erythrocyte Aging; Half-Life; Hemolysis; Male; Quinones; Rats; Rats, Inbred SHR; Ubiquinone

Lipid peroxidation in rat brain mitochondria was induced by NADH in the presence of ADP and FeCl3. CV-2619 inhibited the lipid peroxidation in a concentration-dependent manner; the concentration giving 50% inhibition (IC50) was 84 microM. In addition, the inhibitory effect of CV-2619 was strongly enhanced by adding substrates of mitochondrial respiration; when succinate, glutamate, or succinate plus glutamate was added, the IC50 of CV-2619 was changed to 1.1, 10, or 0.5 microM, respectively. Metabolites of CV-2619 also inhibited the lipid peroxidation. The inhibitory effect of CV-2619 on mitochondrial lipid peroxidation disappeared when TTFA, an inhibitor of complex II in mitochondrial respiratory chain, was added. The results indicate that in mitochondria CV-2619 is changed to its reduced form which inhibits lipid peroxidation.

Topics: Animals; Antimycin A; Benzoquinones; Brain; Coenzymes; gamma-Aminobutyric Acid; Lipid Peroxides; Male; Mitochondria; NAD; Oxygen Consumption; Pantothenic Acid; Quinones; Rats; Rats, Inbred Strains; Rotenone; Thenoyltrifluoroacetone; Ubiquinone; Vitamin E

The effects of a novel compound, 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone, CV-2619), on cerebral and renal vascular changes were examined in stroke-prone spontaneously hypertensive rats (SHRSP) and in rats with experimentally induced hypertension. CV-2619 (35 mg/kg/day, p.o.) significantly inhibited the onset of cerebrovascular lesions (stroke) and the elevation of blood pressure in SHRSP with mild hypertension. A higher dose (2 X 50 mg/kg/day, p.o.) clearly delayed the onset of both stroke and proteinuria without any effect on the blood pressure in SHRSP with severe hypertension. In DOCA-salt hypertensive rats, CV-2619 (2 X 5 or 2 X 25 mg/kg/day, p.o.) dose-dependently inhibited decreases in body weight and water balance and the development of cerebral and renal vascular changes. These results suggest that CV-2619 inhibits the development of stroke and renal vascular lesions in hypertensive rats.

Topics: Animals; Benzoquinones; Blood Pressure; Body Weight; Brain; Cerebrovascular Disorders; Hypertension; Kidney; Male; Quinones; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Time Factors; Ubiquinone; Water-Electrolyte Balance

The concentrations of acetylcholine (Ach) and choline in various brain regions of rats with and without cerebral ischemia and the effects of 6-(10-hydroxy-decyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone, CV-2619) on the levels of these parameters were investigated. Cerebral ischemia was induced by a 200-sec occlusion of both common carotid arteries in animals in which both vertebral arteries had been permanently cauterized. The concentrations of Ach and choline in the brain were determined by means of pyrolysis gas chromatography. In normal rats, CV-2619 (10, 30 and 100 mg/kg, i.p.) did not alter the concentrations of Ach and choline in the brain regions examined. In the ischemic rats, a significant decrease in Ach and a marked increase in choline were observed in the cerebral cortex, hippocampus, striatum, and diencephalon. A slight increase in the concentration of choline was also observed in the cerebellum and brain stem. Pretreatment with CV-2619 (10 mg/kg, i.p.) inhibited the decrease in Ach and the increase in choline in the forebrain regions. Moreover, the same dose of CV-2619 inhibited the increment of lactate content and tended to inhibit the decrement of ATP content in the cerebral cortex. These results indicate that CV-2619 inhibits alterations of the concentrations of Ach and choline in the brain of the ischemic rats; this inhibition may be due to the ameliorating effect of CV-2619 on the disturbance of cerebral energy metabolism under ischemic conditions.

Topics: Acetylcholine; Adenosine Triphosphate; Animals; Benzoquinones; Brain; Brain Ischemia; Choline; Energy Metabolism; Lactates; Lactic Acid; Male; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

An experimental model of amnesia induced by cerebral ischemia after one-trial passive avoidance learning was established to test the effects of a novel compound, 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (idebenone, CV-2619), and some commonly used drugs in rats. One day after the vertebral artery was electrocauterized bilaterally, the common carotid artery was transiently occluded bilaterally to produce cerebral ischemia. The amnesia was estimated by the response latency for a rat to step from a light safety compartment to a dark compartment in which a foot-shock was given. The results of the retention test given 24 hr after the ischemia indicated that amnesia was successfully produced when the 200-600 sec ischemia was provided within 20 min after the avoidance learning. The effects of drugs on the amnesia induced by a 200-sec ischemia immediately after the avoidance learning were as follows: CV-2619 (10, 30 mg/kg, i.p. or p.o.) given before the retention test significantly increased the response latency, indicating a reversal effect on the amnesia. Physostigmine (0.1, 0.2 mg/kg, i.p.) and arginine-vasopressin (10 micrograms/kg, s.c.) were also effective, and calcium hopantenate (500 mg/kg, p.o.) showed a slight reversal action. Furthermore, CV-2619 (10 mg/kg, i.p.), given before or after the ischemia, significantly inhibited the appearance of amnesia.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Amnesia; Animals; Arginine Vasopressin; Avoidance Learning; Benzoquinones; Brain Ischemia; Conditioning, Operant; gamma-Aminobutyric Acid; Humans; Male; Pantothenic Acid; Physostigmine; Quinones; Rats; Rats, Inbred Strains; Time Factors; Ubiquinone

Topics: Animals; Benzoquinones; Brain Chemistry; Lipid Peroxides; Male; Malondialdehyde; Oxidation-Reduction; Quinones; Rats; Rats, Inbred Strains; Ubiquinone; Vitamin E

Effects of CV-2619 (10 and 30 mg/kg/day, p.o.) or ubiquinone-10 (Q-10, 10 mg/kg/day, p.o.) treatment for 5 weeks on systolic blood pressure (SBP) and myocardial energy metabolism were studied in spontaneously hypertensive rats of 20 weeks of age. The systolic blood pressure was about 205 mmHg at the start of the experiment, and a slight increase was noted thereafter in the control (vehicle) group. CV-2619, but not Q-10, inhibited the increase in the blood pressure. At 25 weeks of age, cardiac hypertrophy was noted to the same extent in either treated group. Myocardial contents of glycolytic intermediates (glycogen, glucose, pyruvate and lactate) and creatine phosphate (Cr-P), ATP, ADP, and AMP were not significantly influenced by CV-2619 or Q-10 treatment. CV-2619, however, significantly increased the energy charge, an index of myocardial energy state, with higher dose and lowered the lactate/pyruvate ratio with either dose. These results suggest that CV-2619 has a mild antihypertensive effect and improves the myocardial energy state in the hypertrophied heart during the sustained phase of hypertension in SHR rats.

Topics: Animals; Benzoquinones; Blood Pressure; Body Weight; Cardiomegaly; Cyclic AMP; Electrocardiography; Energy Metabolism; Heart Rate; Heart Ventricles; Hypertension; Male; Myocardium; Organ Size; Phosphoric Acids; Proteins; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

Antidote actions of CV-2619 and ubiquinone-10 (Q-10) against adriamycin (ADM) cardiotoxicity were studied in spontaneously hypertensive rats. ADM (1 mg/kg/day, i.p.) elicited widening of the QRS complex in the ECG. The widening of the QRS complex was counteracted by a 10-day treatment with CV-2619 (10 and 30 mg/kg/day, p.o.) or Q-10 (10 mg/kg/day, p.o.), which was started on the 15th day of the ADM treatment. CV-2619 or Q-10, however, did not influence ADM-induced decrease in body and heart ventricular weights. Systemic hypotension caused by adriamycin was accelerated by CV-2619 or Q-10. The ADM treatment significantly decreased myocardial glycogen and glucose contents, while it did not affect the lactate content. Furthermore, ADM did not affect the myocardial content of adenine nucleotides, but significantly increased that of creatine phosphate. CV-2619 or Q-10 medication did not counteract changes in these contents by ADM. On the contrary, both agents decreased the lactate content and increased the phosphorylation potential, an index of myocardial energy state. In conclusion, CV-2619 might be as effective as Q-10 to protect the heart against ADM cardiotoxicity, and both test agents improved the myocardial energy state.

Topics: Animals; Benzoquinones; Blood Pressure; Body Weight; Doxorubicin; Electrocardiography; Energy Metabolism; Heart Rate; Heart Ventricles; Hypertension; Male; Myocardium; Organ Size; Phosphoric Acids; Phosphorylation; Proteins; Quinones; Rats; Rats, Inbred Strains; Ubiquinone

Effects of CV-2619 and ubiquinone-10 (Q-10) on the energy metabolism of red blood cells (RBC) of Sprague Dawley rats were studied in the presence or absence of NaF. NaF (0.3--10 mM) dose-dependently decreased the ATP and lactate contents of the RBC. In the presence of NaF (1.5 mM), ATP content decreased to about 30% of the control. Phosphofructokinase (PFK) was markedly activated, while glyceraldehydephosphate dehydrogenase (GAPDH) and enolase were inhibited by NaF. Thus, the decrease in ATP by NaF might be attributed to retarded glycolysis due to inhibition of the latter two enzymes. The decrease in ATP by NaF (1.5 mM) was dose-dependently inhibited by CV-2619 (0.3--30 microM). Inhibition of enolase and activation of PFK by NaF were still noted even in the presence of CV-2619. Inhibition of GAPDH by NaF, however, was released by CV-2619. Q-10 (1--100 microM) did not affect the ATP levels decreased by NaF. It could be concluded that CV-2619 counteracted the NaF-induced decrease in the ATP level by accelerating the glycolytic flux through the GAPDH step, which was a rate-limiting one in the presence of NaF. Q-10, however, had no effect on the glycolytic flux.

Topics: Adenosine Triphosphate; Animals; Benzoquinones; Dose-Response Relationship, Drug; Energy Metabolism; Erythrocytes; Glucose; Glycolysis; In Vitro Techniques; Lactates; Lactic Acid; Male; Quinones; Rats; Rats, Inbred Strains; Sodium Fluoride; Time Factors; Ubiquinone