Therapeutic role of coenzyme Q10 in Parkinson's disease

Mitochondrial dysfunction has been well established to occur in Parkinson's disease (PD) and appears to play a role in the pathogenesis of the disorder. A key component of the mitochondrial electron transport chain (ETC) is coenzyme Q10, which not only serves as the electron acceptor for complexes I and II of the ETC but is also an antioxidant. In addition to being crucial to the bioenergetics of the cell, mitochondria play a central role in apoptotic cell death through a number of mechanisms, and coenzyme Q10 can affect certain of these processes. Levels of coenzyme Q10 have been reported to be decreased in blood and platelet mitochondria from PD patients. A number of preclinical studies in in vitro and in vivo models of PD have demonstrated that coenzyme Q10 can protect the nigrostriatal dopaminergic system. A phase II trial of coenzyme Q10 in patients with early, untreated PD demonstrated a positive trend for coenzyme Q10 to slow progressive disability that occurs in PD.