Hydrogen (H2) has been widely used in the chemical industry as a reducing agent. As the researches move along, increasing attention has been paid to its biological functions. The selective antioxidant effect of hydrogen is considered to be the main reason for medical applications. So far, many studies have confirmed its potential protective effects on ischemia/reperfusion injury of multiple organs, neurodegenerative diseases, bone and joint diseases, and respiratory diseases, opening a new era in the medical research and application of H2. Increasing studies have focused on its biological effects and molecular mechanisms in the treatment of different diseases. In this paper, we review the biological effects, molecular mechanisms and methods of H2 supply. We do hope that the advances in materials science can be better translated into medical applications and solve clinical problems. The medical application of H2 is promising, and how to prepare an H2 sustained-release system to achieve a sustained and stable H2 supply in the body and ultimately improve the therapeutic effect of H2 is a problem worthy of further investigation.
Keywords: anti-allergic reactions; anti-apoptotic effect; anti-inflammatory; antioxidant; biological effects; energy generation; hydrogen; molecular mechanisms.