[Hydrogen and oxidative stress injury--from an inert gas to a medical gas].

Oxidative stress is intensive cellular oxidation caused by redundant reactive oxygen species (ROS) or free radicals. Redundant ROS causes DNA fracture, lipid peroxidation and protein inactivation, thus leading to severe cell damage. Recent studies have shown that hydrogen is a good anti-oxidant. It selectively reduces the hydroxyl radical, the most cytotoxic of ROS; however, it does not react with other ROS, which play physiological roles. As a result, it could protect tissues against oxidative stress injuries, such as ischemia/reperfusion injury of the heart, liver and intestine, cisplatin nephrotoxicity, sepsis and colon inflammation. As a medical gas, hydrogen may have a prospect for far-reaching clinical application.