An old medicine as a new drug to prevent mitochondrial complex I from producing oxygen radicals.

Here, we demonstrate that OP2113 (5-(4-Methoxyphenyl)-3H-1,2-dithiole-3-thione, CAS 532-11-6), synthesized and used as a drug since 1696, does not act as an unspecific antioxidant molecule (i.e., as a radical scavenger) but unexpectedly decreases mitochondrial reactive oxygen species (ROS/H2O2) production by acting as a specific inhibitor of ROS production at the IQ site of complex I of the mitochondrial respiratory chain. Studies performed on isolated rat heart mitochondria also showed that OP2113 does not affect oxidative phosphorylation driven by complex I or complex II substrates. We assessed the effect of OP2113 on an infarct model of ex vivo rat heart in which mitochondrial ROS production is highly involved and showed that OP2113 protects heart tissue as well as the recovery of heart contractile activity. This work represents the first demonstration of a drug authorized for use in humans that can prevent mitochondria from producing ROS/H2O2. OP2113 therefore appears to be a member of the new class of mitochondrial ROS blockers (S1QELs) and could protect mitochondrial function in numerous diseases in which ROS-induced mitochondrial dysfunction occurs. These applications include but are not limited to aging, Parkinson's and Alzheimer's diseases, cardiac atrial fibrillation, and ischemia-reperfusion injury.

Déclaration de conflit d'intérêts

We report here that D.D. and P.D. are listed as inventors on pending and issued patent applications related to the molecule OP2113 described in this work (USA US62/215,215; France 15 184 217.6; France EP 17 159 691.9). P.D. is one of the founders of the OP2 drugs company. The funding sources had no role in the study design or the analysis and interpretation of data or in the decision to submit the article for publication. This does not alter our adherence to PLOS ONE policies on sharing data and materials.