ubiquinone and Nerve-Degeneration

Coenzyme Q

Topics: Adult; Aged; Ataxia; Calcium-Binding Proteins; Cell Adhesion Molecules, Neuronal; Collectins; Cross-Sectional Studies; Female; Genetic Loci; Genetic Predisposition to Disease; Genetic Variation; Genome-Wide Association Study; Genotype; Humans; Male; Middle Aged; Mitochondrial Diseases; Muscle Weakness; Nerve Degeneration; Nerve Tissue Proteins; Neural Cell Adhesion Molecules; Neurons; Polymorphism, Single Nucleotide; Receptors, Scavenger; Ubiquinone

The authors summarized the evidence supporting neuroprotection based on the data available in the literature. In vivo and in vitro studies have indicated that many compounds can decrease neurodegeneration, excitotoxicity, oxidative stress, protein aggregation, disturbance of Ca2+ homeostasis and compensate the energy impairment. Selegiline, rasagiline, dopamine agonists and other molecules (ubiquinone, kynurenic acid, tocopherol, creatine, glatiramer acetate) exert neuroprotective effects in preclinical studies. Much less clinical data are available regarding neuroprotection in different neurological disorders. In this review, such preclinical and clinical evidences are summarized.

Topics: Animals; Creatine; Dopamine Agonists; Glatiramer Acetate; Humans; Indans; Kynurenic Acid; Micronutrients; Nerve Degeneration; Neurodegenerative Diseases; Neuroprotective Agents; Oxidative Stress; Parkinson Disease; Peptides; Selegiline; Tocopherols; Ubiquinone

An open-label dose-escalation trial was performed to assess the safety and tolerability of high doses of coenzyme Q10 (CoQ10) in ALS. CoQ10, a cofactor in mitochondrial electron transfer, may improve the mitochondrial dysfunction in ALS. In this study, CoQ10 was safe and well tolerated in 31 subjects treated with doses as high as 3,000 mg/day for 8 months.

Topics: Amyotrophic Lateral Sclerosis; Central Nervous System; Coenzymes; Dose-Response Relationship, Drug; Drug Tolerance; Energy Metabolism; Female; Free Radical Scavengers; Humans; Male; Maximum Tolerated Dose; Middle Aged; Mitochondria; Nerve Degeneration; Neurons; Neuroprotective Agents; Ubiquinone

The present study was carried out to elucidate the effects of coenzyme Q(10) (CoQ(10)) against cognitive impairments induced by dichlorvos (DDVP). We have previously shown organophosphate, DDVP-induced impairments in neurobehavioral indices viz. rota rod, passive avoidance, and water maze tests. In addition to this, we have also reported that chronic DDVP exposure leads to decreased mitochondrial electron transfer activities of cytochrome oxidase along with altered mitochondrial complexes I-III activity. Administration of CoQ(10) (4.5 mg/kg, i.p. for 12 weeks prior to DDVP administration daily) to DDVP-treated rats improved cognitive performance in passive avoidance task and Morris water maze test. Furthermore, CoQ(10) treatment also reduced oxidative stress (as evident by reduced malondialdehyde, decreased ROS and increased Mn-SOD activity) in DDVP-treated rats' hippocampus region, along with enhanced activity of complexes I-III and complex IV. Electron microscope studies of rat hippocampus mitochondria revealed that CoQ(10) administration leads to near normal physiology of mitochondria with well-defined cristae compared with DDVP-treated animals where enlarged mitochondria with distorted cristae are observed. CoQ(10) administration also attenuated neuronal damage in hippocampus as evident from histopathological studies. These results demonstrate the beneficial effects of CoQ(10) against organophosphate-induced cognitive impairments and hippocampal neuronal degeneration.

Topics: Animals; Avoidance Learning; Cognition Disorders; Dichlorvos; Disease Models, Animal; Drug Administration Schedule; Hippocampus; Male; Maze Learning; Mitochondria; Nerve Degeneration; Oxidative Stress; Proton Pumps; Rats; Rats, Wistar; Ubiquinone; Vitamins

To investigate the possibility that mitochondrial oxidative damage, oxidative DNA damage or both contribute to the neurodegenerative process of Alzheimer's disease (AD), we employed high-performance liquid chromatography using an electrochemical detector to measure the concentrations of the reduced and oxidized forms of coenzyme Q-10 (CoQ-10) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the cerebrospinal fluid (CSF) of 30 patients with AD and in 30 age-matched controls with no neurological disease. The percentage of oxidized/total CoQ-10 (%CoQ-10) in the CSF of the AD group (78.2 +/- 18.8%) was significantly higher than in the control group (41.3 +/- 10.4%) (P < 0.0001). The concentration of 8-OHdG in the CSF of AD patients was greater than in the CSF of controls (P < 0.0001) and was positively correlated with the duration of illness (r(s) = 0.95, P < 0.0001). The %CoQ-10 was correlated with concentrations of 8-OHdG in the CSF of AD patients (r(s) = 0.66, P < 0.001). The present study suggests that both mitochondrial oxidative damage and oxidative DNA damage play important roles in the pathogenesis of early AD development.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Aged, 80 and over; Alzheimer Disease; Biomarkers; Brain; Brain Chemistry; Deoxyguanosine; DNA Damage; Female; Free Radicals; Humans; Male; Middle Aged; Mitochondria; Mitochondrial Diseases; Nerve Degeneration; Oxidative Stress; 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

The neurotoxicity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, which produces Parkinsonism, is mediated by its metabolite 1-methyl-4-phenylpyridinium ion (MPP+). When injected into the striatum MPP+ is accumulated by dopaminergic nerve terminals and is then retrogradely transported to the substantia nigra compacta. The mechanism by which it mediates cell death involves both inhibition of complex I of the electron transport chain and free radical generation. In the present experiments we found that administration of the free radical spin trap N-tert-butyl-alpha-(2-sulfophenyl) nitrone (S-PBN) significantly attenuated substantia nigra cell loss produced by MPP+ administration into rat striatum. We also found that coadministration of coenzyme Q10 with nicotinamide, which attenuates energy depletion, significantly blocked MPP(+)-induced substantia nigra damage. Last, we found that a single administration of MPP+ into rat striatum can produce progressive cell loss in the substantia nigra and that administration of S-PBN starting 7 days after administration of MPP+ can block the ensuing neuronal damage. These observations suggest that a one-time exposure to a neurotoxic agent may result in progressive neuronal degeneration mediated by oxidative stress.

Topics: 1-Methyl-4-phenylpyridinium; Animals; Coenzymes; Cyclic N-Oxides; Dopamine Agents; Drug Combinations; Ions; Male; Nerve Degeneration; Niacinamide; Nitrogen Oxides; Oxidative Stress; Rats; Rats, Sprague-Dawley; Spin Labels; Substantia Nigra; Time Factors; 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

During aging the human brain shows a progressive increase in levels of dolichol, a reduction in levels of ubiquinone, but relatively unchanged concentrations of cholesterol and dolichyl phosphate. In a neurodegenerative disease, Alzheimer's disease, the situation is reversed with decreased levels of dolichol and increased levels of ubiquinone. The concentrations of dolichyl phosphate are also increased, while cholesterol remains unchanged. This study shows that the isoprenoid changes in Alzheimer's disease differ from those occurring during normal aging and that this disease cannot, therefore, be regarded as a result of premature aging. The increase in the sugar carrier dolichyl phosphate may reflect an increased rate of glycosylation in the diseased brain and the increase in the endogenous anti-oxidant ubiquinone an attempt to protect the brain from oxidative stress, for instance induced by lipid peroxidation.

Topics: Adult; Aged; Aged, 80 and over; Aging; Alzheimer Disease; Animals; Brain Chemistry; Cells, Cultured; Cholesterol; Dolichol Phosphates; Dolichols; Humans; Lipid Metabolism; Mevalonic Acid; Middle Aged; Nerve Degeneration; Polyisoprenyl Phosphates; Rats; Ubiquinone

Cultured neurons from rat dorsal root ganglia and cerebral cortex were infected with Sendai virus, which gives a productive replication with lysis of most neurons, and with the RW strain of mumps virus, which undergoes defective replication causing degeneration of only 30-40% of the neurons within 5 days after initial infection. In Sendai virus-infected cells the amount of polyisoprenoid lipids was enhanced. In mumps virus-infected cultures there were transient reductions in the contents of cholesterol, dolichol, and ubiquinone-9 in the cultures, whereas the reduction in the ubiquinone-10 level was progressive, reaching 20% of its original value 21 days after infection. Treatment of mumps virus-infected cultures with ubiquinone-10 protected the neurons from degeneration, whereas no effects were observed on exposure to ubiquinone-9. Linolenic acid (18:3) and arachidonic acid (20:4), but not myristic acid (14:0) and palmitic acid (16:0), also had significant neuroprotective effects.

Topics: Animals; Cell Survival; Cells, Cultured; Cerebral Cortex; Cholesterol; Dolichols; Fatty Acids, Nonesterified; Ganglia, Spinal; Kinetics; Mumps virus; Nerve Degeneration; Neurons; Parainfluenza Virus 1, Human; Peroxides; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; tert-Butylhydroperoxide; Time Factors; Ubiquinone; Virus Replication

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

Topics: Amino Acids; Brain Chemistry; Brain Diseases; Cerebellum; Cerebral Cortex; Cerebrosides; Cholesterol; Electroencephalography; Glycogen; Growth Disorders; Hair; Humans; Infant; Male; Nerve Degeneration; Pedigree; Phenobarbital; Phenytoin; Phospholipids; Plasmalogens; Seizures; Ubiquinone; Vitamin E