Abstract P177: Traditional Chinese Medication Qiliqiangxin Inhibits Cardiac Hypertrophy, Remodeling, and Dysfunction During Chronic Pressure Overload in Mice

Abstract

Qiliqiangxin (QL), a traditional Chinese medicine, has been used in the treatment of chronic heart failure. However, whether QL can prevent cardiac hypertrophy and remodeling in the hypertensive is unknown. We here compared the effects of QL with Losartan on the development of cardiac hypertrophy in a mice model of pressure overload. Constriction of transverse aorta (TAC) or sham operation was imposed to C57B/L6 mice and QL (0.6mg/Kg/day), Losartan (13.4mg/Kg/day) or vehicle was then administrated to them. Cardiac hypertrophy, remodeling, functions and fibrosis were evaluated by echocardiography, catheterization, histology, and examination of specific gene expression and ERK phosphorylation. Local apoptosis, autophagy, TNF-α/IGF-1, angiotensin II type 1 receptor (AT1-R), and especially the proliferation of cardiomyocytes and phosphorylation of ErbB2 and ErbB4 were examined in vivo to elucidate the mechanisms. Two weeks later, TAC resulted in a significant cardiac hypertrophy in vehicle group, which was significantly suppressed in either QL or Losartan group. At the end of 4 weeks, QL treatment effectively abrogated TAC-induced the development of myocardial remodeling, dysfunction, fibrosis, and the increases in apoptosis, autophagy, TNF-α to IGF-1 ratio and AT1-R expression, which were comparable to Losartan treatment. However, QL, but not Losartan, enhanced proliferation of cardiomyocytes at 4 weeks after TAC, which was paralleled with dowregulation of C/EBP β , upregulation of CITED4 , and increases in ErbB2 and ErbB4 phosphorylation. Thus, QL inhibits myocardial inflammation and cardiomyocyte death, and promotes cardiomyocyte proliferation, leading to an ameliorated cardiac remodeling and function in a mice model of pressure overload. The possible mechanisms may involve inhibition of AT1-R and activation of ErbB receptors.