MitoQ for Neurologic Disease

MitoQ, an antioxidant drug under development by Antipodean Pharmaceuticals Inc, may have potential in treating multiple sclerosis in addition to other neurologic diseases.

MitoQ is a mitochondria-targeted antioxidant molecule that may have potential in treating multiple sclerosis (MS), Parkinson’s disease, and Alzheimer’s disease. Scientists believe that MitoQ is a neuroprotective agent. Using an autoimmune encephalomyelitis (EAE) mouse model, which is a model of MS, investigators in Oregon administered MitoQ to determine whether the drug had any potential to ameliorate symptoms of MS.

In addition to a reduction in neurological disabilities in the EAE mice, researchers noted a suppression of inflammatory markers such as inflammatory cytokines and chemokines and a reduced rate of spinal neuron loss with use of MitoQ. An in vitro model of MS pathophysiology in a culture of neurons and glial cells, which support the activity of neurons in the brain, revealed a possible mechanism of the effects of MitoQ in reducing the pathologic inflammation and oxidative stress that occur in MS.

MitoQ is orally active, meaning that it would add to a growing arsenal of oral therapies for MS. As of 2007, Antipodean Pharmaceuticals Inc was in phase II clinical trials investigating the efficacy of MitoQ in Parkinson’s disease. Investigators with Antipodean also seek an indication for limiting the liver damage associated with hepatitis C virus (HCV) infection. According to ClinicalTrials.gov, both phase II studies are complete, and another phase II study in nonalcoholic fatty liver disease was terminated.

Phase III trials for HCV liver damage and Parkinson’s disease have not yet begun despite the fact that phase II trials in Parkinson’s disease ended in 2010 and phase II trials in HCV ended in 2008. The long delay suggests unpromising results in the phase II trials. However, with the results of this animal study, investigators may attempt a trial of MitoQ in MS.

Structurally, MitoQ (also known as mitoquinone mesylate) resembles coenzyme Q10, a mitochondrial antioxidant that is critical in maintaining energy metabolism in mitochondria. Previous studies have shown that MitoQ reduces oxidative DNA damage in human peripheral blood mononuclear cells. MitoQ is different from other antioxidant molecules in that MitoQ exerts more powerful antioxidant activity when the membrane potential of mitochondria is higher.

It should be noted that MitoQ is just one of many compounds under investigation for treating MS. Animal data may not reflect activity in humans, and it is too early to determine whether MitoQ will ever be available as a treatment for MS.