Skeletal muscle response to inflammation--lessons for chronic obstructive pulmonary disease.

To describe how inflammation affects muscle adaptation and performance in people with chronic obstructive pulmonary disease. In chronic obstructive pulmonary disease, an increasingly sedentary lifestyle is a primary contributor to muscle dysfunction that results in a loss of mobility and independence and, ultimately, mortality. Given the systemic chronic inflammation and profound limb muscle atrophy in chronic obstructive pulmonary disease, it is tempting to speculate that the inflammatory process is deleterious to skeletal muscle. In healthy people, however, the inflammatory process initially is dominated by a destructive phase that is tightly regulated and modulates a reparative, regenerative phase. Although the inflammatory process and associated oxidative stress is more closely connected to muscle wasting in animal models of chronic obstructive pulmonary disease, the causative role of inflammation toward muscle atrophy and weakness in people with chronic obstructive pulmonary disease has not been definitively shown. Anti-inflammatory interventions aimed toward tempering muscle wasting and weakness in chronic obstructive pulmonary disease may not prove to be beneficial because of longer-term disruption of the regeneration of muscle tissue. Temporally and spatially targeted interventions aimed toward ameliorating oxidative stress, such as antioxidants, nutritional supplements, and chronic exercise training, may optimize outcomes toward maintaining muscle mass and performance.