H_2O_2, a Necessary Evil for Cell Signaling

摘要

For many years, hydrogen peroxide (H_2O_2) was viewed as the inevitable but unwanted by-product of an aerobic existence. Given the damage inflicted by H_2O_2, it was assumed that the faster the elimination of this toxic waste, the better for the cell.However, as highlighted in recent forums (1,2), we now know that mammalian cells produce H_2O_2 to mediate diverse physiological responses such as cell proliferation, differentiation, and migration (3, 4). This has led to implications of cellular "redox" signaling in regulating normal processes and disease progression, including angiogenesis, oxidative stress and aging, and cancer. This changing view of H_2O_2 has partly evolved from a clearer understanding of redox chemistry as it affects biology—that is, cellular signaling that is linked to reductive-oxidative-based mechanisms. As the components and mechanisms involved in performing cellular redox chemistry become better defined, new areas of research are emerging as to how the cells spatially andtemporally channel H_2O_2 into specific signaling pathways to achieve desired cellular outcomes.