Acute respiratory distress syndrome (ARDS) is a severe form of acute lung injury, characterized by rapid breathing, shortness of breath, and a low blood oxygen level. It occurs in as many as 17 percent of all COVID-19 cases and can lead to respiratory failure and death. Findings presented in a recent review suggest that extracellular superoxide dismutase (EcSOD), a potent antioxidant enzyme produced by the muscles during exercise, can reduce the risk of developing ARDS.
A critical feature of the pathogenesis of ARDS is an excessive immune response that leads to increased production of reactive oxygen species and pro-inflammatory mediators in the lungs. Evidence indicates that EcSOD is highly expressed in lung tissues, where it inhibits many of the pathological features of ARDS and acts as a scavenger of superoxide. Loss of EcSOD activity in mice markedly increases risk of death due to ARDS, however.
An abundance of evidence demonstrates that even a single session of exercise can boost EcSOD production in muscles. Taken together, these findings suggest that exercise could provide protection against ARDS by upregulating EcSOD production.