Aerobic exercise training improves skeletal muscle function and Ca2+ handling-related protein expression in sympathetic hyperactivity-induced heart failure

作者：Bueno C R Jr; Ferreira J C B; Pereira M G; Bacurau A V N; Brum P C^*

来源：Journal of Applied Physiology, 2010, 109(3): 702-709.

DOI：10.1152/japplphysiol.00281.2010

• cardiac diseases
• muscular abnormalities
• treadmill running
• Ca2+ transient

Bueno CR Jr, Ferreira JC, Pereira MG, Bacurau AV, Brum PC. Aerobic exercise training improves skeletal muscle function and Ca2+ handling-related protein expression in sympathetic hyperactivity-induced heart failure. J Appl Physiol 109: 702-709, 2010. First published July 1, 2010; doi: 10.1152/japplphysiol.00281.2010.-The cellular mechanisms of positive effects associated with aerobic exercise training on overall intrinsic skeletal muscle changes in heart failure (HF) remain unclear. We investigated potential Ca2+ abnormalities in skeletal muscles comprising different fiber compositions and investigated whether aerobic exercise training would improve muscle function in a genetic model of sympathetic hyperactivity-induced HF. A cohort of male 5-mo-old wild-type (WT) and congenic alpha(2A)/alpha(2C) adrenoceptor knockout (ARKO) mice in a C57BL/6J genetic background were randomly assigned into untrained and trained groups. Exercise training consisted of a 8-wk running session of 60 min, 5 days/wk (from 5 to 7 mo of age). After completion of the exercise training protocol, exercise tolerance was determined by graded treadmill exercise test, muscle function test by Rotarod, ambulation and resistance to inclination tests, cardiac function by echocardiography, and Ca2+ handling-related protein expression by Western blot. alpha(2A)/alpha(2C)ARKO mice displayed decreased ventricular function, exercise intolerance, and muscle weakness paralleled by decreased expression of sarcoplasmic Ca2+ release-related proteins [alpha(1)-, alpha(2)-, and beta(1)-subunits of dihydropyridine receptor (DHPR) and ryanodine receptor (RyR)] and Ca2+ reuptake-related proteins [sarco(endo) plasmic reticulum Ca2+-ATPase (SERCA) 1/2 and Na+/Ca2+ exchanger (NCX)] in soleus and plantaris. Aerobic exercise training significantly improved exercise tolerance and muscle function and reestablished the expression of proteins involved in sarcoplasmic Ca2+ handling toward WT levels. We provide evidence that Ca2+ handling-related protein expression is decreased in this HF model and that exercise training improves skeletal muscle function associated with changes in the net balance of skeletal muscle Ca2+ handling proteins.

• 出版日期2010-9