Anti-inflammatory effects of exercise training in the skeletal muscle of patients with chronic heart failure

OBJECTIVES: The aim of this study was to assess the effects of regular physical exercise on local inflammatory parameters in the skeletal muscle of patients with chronic heart failure (CHF). BACKGROUND: Inflammatory activation with increased serum cytokine levels and expression of inducible nitric oxide synthase (iNOS) in the myocardium and peripheral skeletal muscles has been described in CHF. METHODS: Twenty male patients with stable CHF (left ventricular ejection fraction 25 +/- 2%; age 54 +/- 2 years) were randomized to a training group (n = 10) or a control group (n = 10). At baseline and after six months, serum samples and vastus lateralis muscle biopsies were obtained. Serum tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-1-beta levels were measured by enzyme-linked immunosorbent assay, local cytokine, and iNOS expression by real-time polymerase chain reaction. RESULTS: Exercise training improved peak oxygen uptake by 29% in the training group (from 20.3 +/- 1.0 to 26.1 +/- 1.5 ml/kg. min; p < 0.001 vs. control group). While serum levels of TNF-alpha, IL-6, and IL-1-beta remained unaffected by training, local skeletal muscle TNF-alpha decreased from 1.9 +/- 0.4 to 1.2 +/- 0.3 relative U (p < 0.05 for change vs. control group), IL-6 from 71.3 +/- 16.5 to 41.3 +/- 8.8 relative U (p < 0.05 vs. begin), and IL-1-beta from 2.7 +/- 1.1 to 1.4 +/- 0.6 relative U (p = 0.02 vs. control group). Exercise training also reduced local iNOS expression by 52% (from 6.3 +/- 1.2 to 3.0 +/- 1.0 relative U; p = 0.007 vs. control group). CONCLUSIONS: Exercise training significantly reduced the local expression of TNF-alpha, IL-1-beta, IL-6, and iNOS in the skeletal muscle of CHF patients. These local anti-inflammatory effects of exercise may attenuate the catabolic wasting process associated with the progression of CHF.