Exercise for the heart: signaling pathways

// Lichan Tao 1, * , Yihua Bei 2, 3, * , Haifeng Zhang 1 , Junjie Xiao 2, 3 , Xinli Li 1 1 Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China 2 Regeneration and Ageing Lab and Experimental Center of Life Sciences, School of Life Science, Shanghai University, Shanghai 200444, China 3 Shanghai Key Laboratory of Bio-Energy Crops, School of Life Science, Shanghai University, Shanghai 200444, China * These authors have contributed equally to this work Correspondence to: Xinli Li, e-mail: xinli3267_nj@hotmail.com Junjie Xiao, e-mail: junjiexiao@live.cn Keywords: exercise, cardiovascular disease, cardiac growth Received: May 10, 2015      Accepted: July 10, 2015      Published: July 23, 2015 ABSTRACT Physical exercise, a potent functional intervention in protecting against cardiovascular diseases, is a hot topic in recent years. Exercise has been shown to reduce cardiac risk factors, protect against myocardial damage, and increase cardiac function. This improves quality of life and decreases mortality and morbidity in a variety of cardiovascular diseases, including myocardial infarction, cardiac ischemia/reperfusion injury, diabetic cardiomyopathy, cardiac aging, and pulmonary hypertension. The cellular adaptation to exercise can be associated with both endogenous and exogenous factors: 1) exercise induces cardiac growth via hypertrophy and renewal of cardiomyocytes, and 2) exercise induces endothelial progenitor cells to proliferate, migrate and differentiate into mature endothelial cells, giving rise to endothelial regeneration and angiogenesis. The cellular adaptations associated with exercise are due to the activation of several signaling pathways, in particular, the growth factor neuregulin1 (NRG1)-ErbB4-C/EBPβ and insulin-like growth factor (IGF)-1-PI3k-Akt signaling pathways. Of interest, microRNAs (miRNAs, miRs) such as miR-222 also play a major role in the beneficial effects of exercise. Thus, exploring the mechanisms mediating exercise-induced benefits will be instrumental for devising new effective therapies against cardiovascular diseases.