mitoquinone and Mitochondrial-Diseases

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National Knowledge Infrastructure until September 2013 for eligible randomized controlled trials (RCTs), as well as unpublished and ongoing trials.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

Mitochondrial oxidative phosphorylation (OXPHOS) represents the final step in the conversion of nutrients into cellular energy. Genetic defects in the OXPHOS system have an incidence between 1:5,000 and 1:10,000 live births. Inherited isolated deficiency of the first complex (CI) of this system, a multisubunit assembly of 45 different proteins, occurs most frequently and originates from mutations in either the nuclear DNA, encoding 38 structural subunits and several assembly factors, or the mitochondrial DNA, encoding 7 structural subunits. The deficiency is associated with devastating multisystemic disorders, often affecting the brain, with onset in early childhood. There are currently no rational treatment strategies. Here, we present an overview of the genetic origins and cellular consequences of this deficiency and discuss how these insights might aid future development of treatment strategies.

Topics: Antioxidants; Child; Child, Preschool; Developmental Disabilities; Disease Progression; Drug Delivery Systems; Electron Transport Complex I; Energy Metabolism; Humans; Infant; Infant, Newborn; Mitochondrial Diseases; Organophosphorus Compounds; Oxidative Phosphorylation; Plastoquinone; Resveratrol; Stilbenes; Ubiquinone

Mitochondrial oxidative damage contributes to a range of degenerative diseases. Ubiquinones have been shown to protect mitochondria from oxidative damage, but only a small proportion of externally administered ubiquinone is taken up by mitochondria. Conjugation of the lipophilic triphenylphosphonium cation to a ubiquinone moiety has produced a compound, MitoQ, which accumulates selectively into mitochondria. MitoQ passes easily through all biological membranes and, because of its positive charge, is accumulated several hundred-fold within mitochondria driven by the mitochondrial membrane potential. MitoQ protects mitochondria against oxidative damage in vitro and following oral delivery, and may therefore form the basis for mitochondria-protective therapies.

Topics: Administration, Oral; Animals; Cations; Cell Membrane; Humans; Membrane Potential, Mitochondrial; Membrane Potentials; Mitochondria; Mitochondrial Diseases; Models, Biological; Models, Chemical; Organophosphorus Compounds; Oxygen; Quinones; Ubiquinone

Mitochondria have long been known to play a critical role in maintaining the bioenergetic status of cells under physiological conditions. Mitochondria produce large amounts of free radicals, and mitochondrial oxidative damage can contribute to a range of degenerative conditions including cardiovascular diseases (CVDs). Although the molecular mechanisms responsible for mitochondrion-mediated disease processes are not correctly understood, oxidative stress seems to play an important role. Consequently, the selective inhibition of mitochondrial oxidative damage is an obvious therapeutic strategy. This review considers the process of CVD from a mitochondrial perspective and provides a summary of the following areas: reactive oxygen species (ROS) production and its role in pathophysiological processes such as CVD, currently available antioxidants and possible reasons for their efficacy and inefficacy in ameliorating oxidative stress-mediated diseases, and recent developments in mitochondria-targeted antioxidants that concentrate on the matrix-facing surface of the inner mitochondrial membrane. These mitochondrion-targeted antioxidants have been developed by conjugating the lipophilic triphenylphosphonium cation to antioxidant moieties such as ubiquinol. These compounds pass easily through biological membranes and, due to their positive charge, they accumulate several-hundred-fold within mitochondria. In this way they protect against mitochondrial oxidative damage and show potential as a future therapy for CVDs.

Topics: Antioxidants; Cardiovascular Diseases; Diabetes Mellitus; Endothelium, Vascular; Humans; Membrane Potentials; Mitochondria; Mitochondrial Diseases; Nitric Oxide; Organophosphorus Compounds; Oxidative Stress; Reactive Oxygen Species; Reperfusion Injury; Risk Factors; Ubiquinone

The goal of this study was to assess mitochondrial function and ROS production in an experimental model of cocaine-induced cardiac dysfunction. We hypothesized that cocaine abuse may lead to altered mitochondrial function that in turn may cause left ventricular dysfunction. Seven days of cocaine administration to rats led to an increased oxygen consumption detected in cardiac fibers, specifically through complex I and complex III. ROS levels were increased, specifically in interfibrillar mitochondria. In parallel there was a decrease in ATP synthesis, whereas no difference was observed in subsarcolemmal mitochondria. This uncoupling effect on oxidative phosphorylation was not detectable after short-term exposure to cocaine, suggesting that these mitochondrial abnormalities were a late rather than a primary event in the pathological response to cocaine. MitoQ, a mitochondrial-targeted antioxidant, was shown to completely prevent these mitochondrial abnormalities as well as cardiac dysfunction characterized here by a diastolic dysfunction studied with a conductance catheter to obtain pressure-volume data. Taken together, these results extend previous studies and demonstrate that cocaine-induced cardiac dysfunction may be due to a mitochondrial defect.

Topics: Animals; Antioxidants; Cocaine; Cocaine-Related Disorders; Disease Susceptibility; Drug Evaluation, Preclinical; Heart Diseases; Male; Mitochondria, Heart; Mitochondrial Diseases; Molecular Targeted Therapy; Organophosphorus Compounds; Oxygen Consumption; Rats; Rats, Wistar; Reactive Oxygen Species; Ubiquinone