Aps Protect Cardiac Hypertrophy Induced By ISO Via PGC-1α Signaling Pathway

Objective The aim of the present study was to explore the protective effect of Astragalus polysaccharides on isoproterenol(ISO) induced myocardial hypertrophy,focusing on the energy metabolism related mechanism.Methods In animal study, cardiac hypertrophy was induced by ISO(15mg/kg﹒d) intraperitoneal injection. different concentration of APS(200 、400 、800 mg/kg﹒d)and PRO(40 mg/kg﹒d)was given by gavage. 3 weeks later, HMI、LVMI、LVEDP、LVSP hemodynamic parameters were observed; HE staining was performed to evulate Myocardial cell diameter. The m RNA expression of atrial natriuretic peptide( ANP) and PGC-1? was determined by RT-PCR; The protein expression of PGC-1? was dertermined by western blot; the content of FFA、ATP、ADP、AMP were quantified by enzyme-linked immunosorbent assay(ELISA). In cell study, myocardial hypertrophy was induced by ISO(10 μmol/L), and cardiopreotective effects of different concentration of APS(0.1 、1 、10 mg/L) and PRO 2 μ mol/L were observed on ISO induced cardiac hypertrophy. The volume of cardiomyocytes was measured by digestive isolation and computer photograph analysis system; the total protein content was determined by Bradford; The content of FFA、ATP、ADP、AMP were quantified by ELISA. The expression of ANP m RNA were determined by RT-PCR; Western blot were used to quantify protein expression of PGC-1α.Results Animal experiment, compared with control group,ISO model group markedly elevated HMI 、 LVMI 、 LVEDP level and decreased LVSP level,Meanwhile the expression of ANP m RNA were increase and the expression of PGC-1αm RNA and the protein expression of PGC-1α were decreased.Compared with ISO group, The APS for different dose groups were dependently improved hemodynamic index 、ATP/AMP、ATP/ADP ratio and PGC-1α m RNA and protein expression. Cell experiment,compared with the normal control group, ISO model group markedly elevated the cardiomyocyte size, total protein content,and the expression of ANP m RNA,but the protein expression of PGC-1α were decreased.Compared with ISO group, The APS( 0.1 mg/L,1 mg/L,10 mg/L)were dependently improved ATP/AMP 、 ATP/ADP ratio 、 PGC-1α protein expression.Conclusions APS can improve the ISO induced cardiac hypertrophy,which may be improve energy metabolism by PGC-1α.