Oral administration of coenzyme Q10 prevents cytochrome c release from mitochondria induced by 1-methyl-4-phenylpyridinium ion in mouse brain synaptosomes

Coenzyme Q10 (CoQ10) exerts neuroprotective effects in several in vivo and in vitro models of neurodegenerative disorders. However, the mechanisms of action are not fully understood. The aim in this study was to investigate whether oral administration of CoQ10 could inhibit cytochrome c (cyt c) release from mitochondria induced by 1-methyl-4-phenylpyridinium ion (MPP+), which causes dopaminergic cell death by selective inhibition of complex I of the electron transport chain, in mouse brain synaptosomes. An increase of cyt c was detected in the cytosolic fraction from mouse brain synaptosomes treated with MPP+. Oral administration of CoQ10 prevented the mitochondrial cyt c release in the MPP+-treated synaptosomes. In addition, CoQ10 did not affect the MPP+-induced decrease in mitochondrial oxidation-reduction activity and membrane potential in brain synaptosomes. Our findings demonstrate that MPP+-induced mitochondrial cyt c release in brain synaptosomes is prevented by oral administration of CoQ10 independently of mitochondrial dysfunction prior to the cyt c release.