Superoxide- and semiquinone-linked activation of molecular hydrogen in metal-catalyst-free solution.

ABSTRACT: The therapeutic effects of molecular hydrogen (H₂), particularly in ischemia-reperfusion (I/R) injury and deleterious inflammation, have been increasingly attributed to its modulation of redox balance. However, the precise molecular mechanisms underlying H₂-medated redox modulation, particularly in mitochondrial reverse electron transfer (RET)-driven superoxide (O₂•^-) generation, remain unclear. Here we show that under membrane-less in-solution conditions, H₂ modulates O₂•^- kinetics in ways consistent with a tunneling-assisted electron transfer involving SQ radicals, without catalytic metals or hydrogenases. Using enzymatic (xanthine oxidase/hypoxanthine; XO/Hx) and non-enzymatic (potassium superoxide; KO₂

SUBMITTER: Ishibashi T 

PROVIDER: S-EPMC12582930 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature