Influence of moderate and high intensity interval training on infarcted rat diaphragm

Abstract Background Respiratory muscle dysfunction is commonly observed in heart failure (HF) patients and contributes to early fatigue dyspnea. As there no specific pharmacological therapy treat skeletal changes, physical exercise considered an important strategy prevent HF-associated myopathy. However, which type better during HF unsettled. Purpose To evaluate the effects of aerobic high intensity interval (HIIT) training on diaphragm morphometric, biochemical, molecular parameters infarcted rats. Methods Three months after inducing myocardial infarction (MI), male Wistar rats were assigned into three groups: sedentary MI (MI-Sed, n=8), subjected (MI-A, HIIT (MI-HIIT, n=8). Results compared a Sham group (n=8). Exercise was performed treadmill times week for months. Functional capacity test echocardiogram before protocols. Myosin heavy chain (MyHC) isoforms analyzed by electrophoresis; mitogen activated protein kinases (MAPK), NF-κB, TNF-α, Pax-7 expression evaluated Western-blot. Statistical analysis: ANOVA. similarly improved both Infarction size histological analysis did not differ between groups (MI-Sed 27.7±10.8; MI-A 29.6±12.9; MI-HIIT 27.4±12.2% total left ventricle area; p=0.91). Echocardiographic exercise. Cross sectional area fibers (Sham 1922±230; MI-Sed 1808±264; 1926±209; 2007±286 μm2), collagen interstitial fractional 4.93±1.76; 5.01±1.88; 4.55±1.18; 3.94±1.15%), percentage MyHC groups. lower than [Sham 1.15 (0.58–1.44), 1.19 (0.90–2.85), 1.46 (0.77–2.14), 0.46 (0.29–0.66) arbitrary units]. Total p-38 higher other 1.00±0.52; 1.77±0.47; 0.66±0.22; 0.46±0.31 The proteins Conclusion Both improves functional with influence infarction. Funding Acknowledgement Type funding sources: Foundation. Main source(s): FAPESP (São Paulo Research Foundation)