Protective effects of exercise in metabolic disorders are mediated by inhibition of mitochondrial-derived sterile inflammation

While beneficial properties of physical activity and exercise on human health have been extensively reported in literature, the exact mechanism(s) underpinning impacts of exercise are not well understood. Focusing on metabolic disorders, as the main causes of social and economic burden in current century, exercise exhibited promising effects in prevention, alleviation and retardation of these disorders including, type 2 diabetes (T2D), Alzheimer's disease (AD), major depressive disorder (MDD) and obesity. Recent evidence has unmasked the role of mitochondrial dysfunction and chronic inflammation in pathophysiology of these disorders. Despite of the wealth of research on the etiology of metabolic disorders, intimate connections between these diseases, complex pathophysiology and their comorbidity still remains a challenging dilemma. In addition, although physical activity has improving effects on human health, it is not clear that how exercise is able to exert its modulatory effects on outcomes of metabolic disorders. Among several mechanisms, we assumed the hypothesis that exercise mitigates the production of mitochondrial-induced reactive oxygen species (ROS) and danger associated molecular patterns (DAMPs) as the main triggering factors for inflammasome formation. Since inflammasomes are of highly deleterious molecules relevant to pathogenesis of metabolic disorders, we hypothesized that beneficial effects of exercise may be associated with its ability to enhance the mitochondrial biogenesis and glucose transportation through generation of brain derived neurotrophic factor (BDNF). Also, we proposed that boosting impact of exercise on autophagy process accelerates the elimination of damaged mitochondria and thus, results in considerable decrease in production of ROS and DAMPs and consequently sterile inflammation. (C) 2015 Elsevier Ltd. All rights reserved.