The Influence Of Astragalus Polysaccharide On Myocardial Apoptosis In Diabetic Rats

ObjectiveTo discuss the protective effect that the Astragalus polysaccharide on apoptosis of myocardial cell and its mechanism.MethodsIn vivo experimen:55 mg/kg STZ were used as myocardial hypertrophy models by intra-peritoneally injection.Observe the effects of type 1 diabetes cardiomyopathy of the APS 200 mg/kg/d,400 mg/kg/d,800 mg/kg/d.Using the rat blood to get glucose,and using the ultrasound cardiograph to measure cardiac mass index,left ventricular mass index(bmi),LVEDP and LVSP.Myocardial tissue for TUNEL staining to judge the apoptosis.Using Western blot and RT-PCR to text the expression of Bax?Bcl-2?Caspase-3 and PGC-1?.Using ELISE to text ATP,ADP and AMP in the serum.In vitro study:Training rats myocardial cells,with a tendency for 33.3 / L glucose induced,observe APS 200 ?mol/L,400 ?mol/L,800 ?mol/L and APS + PGC-1 ?si RNA groups of high glucose induced myocardial cell injury protection.MTT method is used to test the cell survival rate,Caspase-3 activity is tested.Hoechst 33342 are used to compare the apoptosis of all groups.Using Western blot to text the expression of Bax?Bcl-2 and Caspase-3.ResultsIn vivo experiment:Diabetic cardiomyopathy group compared with controls of HMI,LVMI and LVEDP increased,LVSP;Bax,Caspase-3 and PGC-1? protein expression decreased and the Bcl-2 protein expression increased.ATP/ADP,ATP/AMP ratio is falling,HE staining show cardiac structural was abnormal and the TUNEL result showed that the apoptosis rate was increased significantly.The Diabetic with low,medium and high Astragalus polysaccharides group compare with diabetes cardiomyopathy,the expression of Bax,Caspase-3 is falling and the expression of Bcl-2 and PGC-1? is rising.The ATP/ADP,ATP/AMP ratio is rising.The apoptosis index in TUNEL staining was decreased and the HE staining show that myocardial tissue was reduced.In vitro study:Compared with the control group,the cell was damaged by high glucose and the cell survival rate decreased.In high glucose group,the Caspase-3 activity increases,and the Bax,Caspase-3 and PGC-1? protein expression decreased,the Bcl-2 expression increased.The apoptosis index in Hoechst33342 staining was increased.In the groups with medicine,the Caspase-3 activity is falling,and the expression of the Bax,Caspase-3 is falling and the Hoechst33342 staining result showed that the apoptosis rate was decreased.In the APS(800?mol/L)+ PGC-1?si RNA group,the Caspase-3 activity is higher than the APS(800?mol/L)and the apoptosis index in Hoechst33342 staining was increased.ConclusionsThe APS can improve the apoptosis of myocardial cell,and the mechanism is related to the expression of PGC-1?.