Effects Of Ginsenoside Rg1 On Myocardial Hypertrophy Induced By Iso And The Underlying Mechanism

Objective This study is aimed to investigate the effects and mechanisms of Ginsenoside Rg1(Rg1) on hypertrophy induced by isoprenaline(Iso) in neonatal rat cardiomyocytes. The protective effects and the underlying mechanisms of Rg1 will be explored from energy metabolism and NF-кB /PGC-1α signaling pathway perspective, especially.Methods The primary neonatal rat cardiac myocytes were cultured and the model group were induced by isoproterenol(Iso) 10 μmol/L, so as to observe the effect of different doses(12.5 、25、50 μmol/L) of Ginsenoside Rg1, Nuclear Factor(NF-кB) inhibitor BAY11-7082(5 μmol/L) on hypertrophic myocytes. The Cells were randomly divided into 6 groups: Control group, Iso group, Iso + Rg1(12.5, 25 and 50 umol/L) group and Iso + BAY11-7082 group. The cardiomyocytes volume was measured by digestive isolation and computer photograph analysis system; Total protein contents were assayed by the method of coomassie brilliant blue(Bradford); The expression of adenosine triphosphate(ATP), adenosine monophosphate(AMP) and free fatty acids(FFA) were qualified by enzyme-linked immunosorbent assay(ELISA); The expression of atrial natriuretic peptide(ANP) m RNA were assessed by inverse transcription polymerase chain reaction(RT-PCR); The protein expression of p65, PGC-1α were measured by western blot.Results Compared with the Control group, cell size, total protein content and the level of free fatty acids(FFA) were increased, while ATP/AMP ratio were decreased(P<0.05). Besides, ANP m RNA expression increased and the protein expression of PGC-1α significantly decreased, while p65 were increased(P<0.05). Compared with Iso group, Rg1(25,50 μmol/L) and BAY11- 7082 group could effectively alleviate the hypertrophy induced by Iso, making the cell size and the total protein content decrease by 24.80%,26.56%,33.46% and 29.07%,41.64%,42.44% respectively. Furthermore, the level of FFA decreased and ATP/AMP ratio increased(P<0.05). Meanwhile, the expression of ANP m RNA and p65、PGC-1α protein were both reversed significantly in Rg1(25、50 μmol/L) and BAY11- 7082 group. It is found that the protective effects of Rg1 was obvious and Rg1(50 μmol/L) showed the same influence on cardiomyocytes with BAY11- 7082(5 μmol/L) group.Conclusions Ginsenoside Rg1 shows protective effects on cardiomyocytes hypertrophy induced by Iso obviously. The underlying mechanisms of Ginsenoside Rg1 is partly attributed to NF-кB/PGC-1α signaling pathway, through regulating the amount of FFA, ATP and improving the energy metabolism of hypertrophic myocytes, then exerts its pharmacological role.