) is a colorless, odorless gas that can act as a reducing agent under certain circumstances. Previously considered physiologically an inert and nonfunctional molecule in mammalian cells, H2
largely went ignored until Nature Medicine revealed the antioxidant and cytoprotective effects of hydrogen gas in a focal stroke model. Reactive oxygen species (ROS）is generated inside the body throughout our daily lives as a by-product of the energy metabolism by oxidative phosphorylation, which can cause biofilm system damage and intracellular oxidative phosphorylation disorders. H2
reacts with highly reactive oxidants such as hydroxyl radical (·OH) and peroxynitrite (ONOO-
) inside cells to improve ischemia reperfusion injury. In addition, hydrogen is a potent antiapoptotic and anti-inflammatory agent and can be used for potential medical applications in cells, tissues and organs. As a new antioxidant, hydrogen has the advantages of non-toxicity, easy diffusion and selective neutralization. This review makes a case for supporting hydrogen as a new antioxidant medicine for clinical applications. We also hope to provide a reference for the further study of hydrogen to preserve blood cells in transfusion medicine.