The Evaluation and Quantitation of Dihydrogen Metabolism Using Deuterium Isotope in Rats.

Abstract

This study investigated the quantitative metabolic parameters of molecular hydrogen in vivo using intraperitoneally administered deuterium gas as a tracer, with deuterium enrichment measured in the body water pool. Under physiological conditions in rats, approximately 10% of the administered dose underwent oxidation, providing evidence of antioxidant activity. Neither hypoxic conditions nor endotoxin administration altered deuterium oxidation, whereas pure oxygen inhalation led to a reduction in oxidation. In parallel in vitro experiments using bovine heart submitochondrial particles, hydrogen significantly suppressed superoxide generation at Complex I of the mitochondrial respiratory chain. The authors discuss iron-sulfur clusters as potential mediators of reactive oxygen species production and their interaction with dihydrogen as a plausible mechanistic basis for the observed effects.

Mechanism

Hydrogen is proposed to interact with iron-sulfur clusters in mitochondrial respiratory chain Complex I, thereby reducing superoxide generation. In vivo, approximately 10% of administered hydrogen undergoes oxidation under physiological conditions, consistent with direct antioxidant activity.