Exercise as a Model to Study Interactions Between Oxidative Stress and Inflammation

Abstract

Inflammation is involved in the pathogenesis of insulin resistance, atherosclerosis, neurodegeneration, and tumor growth, and low-grade chronic inflammation appears as a key player in the pathogenesis of several chronic diseases, including type 2 diabetes, cardiovascular disease, cancer and Alzheimer's disease. Given that regular exercise offers protection against all causes of mortality, primarily by protection against atherosclerosis and insulin resistance, we suggest that exercise may exert some of its beneficial health effects by inducing anti-inflammatory actions. During exercise, skeletal muscles release IL-6 into the circulation and muscle-derived IL-6 mediates anti-inflammatory effects. Supplementation with antioxidative vitamins attenuates the systemic IL-6 response to exercise primarily via inhibition of the IL-6 protein release from contracting skeletal muscle per se. Apparently, antioxidants attenuate some of the normal physiological responses to nondamaging exercise. Therefore, the use of antioxidant supplementation may be less desirable from a long-term health perspective. This point of view is partly supported by large-scale studies showing no effect, or even a detrimental effect, of antioxidant supplementation on morbidity and mortality and by studies showing that antioxidants may blunt some of the metabolic effects of regular exercise