Homocysteine Mediated Cardiomyocyte Apoptosis And Lycium Barbarum Polysaccharide Intervention By Endoplasmic Reticulum Stress

Objective To investigate the apoptosis induced by homocysteine(Hcy)through endoplasmic reticulum stress(ERS)in APOE-/-mouse myocardial cells and H9C2 rat myocardial cells,and the intervention effect of lycium barbarum polysaccharide(LBP).Methods 1.Animals: 36 healthy SPF grade male APOE-/-mice aged 6 weeks were randomly divided into control group(CG),homocysteine group(HG),homocysteine + lycium lycium polysaccharide group(HLG),12 mice in each group.CG was given to the general diet and saline was given to the stomach;HG was given a diet containing 1.7% methionine,AIN-93 G.HLG was given a diet containing 1.7% methionine(AIN-93G)and LBP gavage.After 24 weeks of intervention,mice were sacrificed,serum Hcy concentration was detected,cardiac organ coefficients were recorded,TUNEL staining was used to detect the difference in apoptosis of myocardial cells in each group,and expressions of ERS related factors(BIP,ATF6,IRE1,PERK,ero1-alpha,CHOP)were detected by immunohistochemistry and western blot.2.Cells: under the condition of 37 ℃ and 5% CO2 cultivate H9C2 rat myocardial cells,the logarithmic phase test cell is divided into four groups: Control group(CG): 4% fetal bovine serum,high glucose DMEM culture for 48h;Lycium barbarum polysaccharide group(LG): 40mg/L LBP solution was added in 4% fetal bovine serum and high glucose DMEM for 48 h.Homocysteine group(HG): 200 umol/L HCY solution was added to 4% fetal bovine serum and high glucose DMEM for 48 h.Homocysteine + lycium barbarum polysaccharide group(HLG): LBP solution of 40mg/L and HCY solution of 200 umol /L were added to 4% fetal bovine serum and high-glucose DMEM for 48 h.The above model was copied in 96-well plate,24-well plate and 6-well plate to complete CCK8 cell viability detection,Tunel apoptosis detection,cell immunofluorescence,western blot and other tests,and detect the expression of ERS related factors.Results 1.Animal: compared with CG,HG serum Hcy concentration was significantly increased,cardiac organ coefficient was increased,and myocardial cell apoptosis was increased.Immunohistochemistry and western blot results of ERS related factors indicated that the expression level of HG was significantly higher than that of CG,while the expression level of HLG was lower than that of H group,and the difference was statistically significant(P < 0.05).2.Cells: there were no significant differences in cell viability,apoptosis and ERS related factors expression between LG group and CG group.Compared with CG group,HG group showed decreased cell viability,increased apoptosis index and increased expression of ERS related factors.Compared with the HG group,the HLG group showed an increase in cell viability,a decrease in apoptosis index,and a pullback in the expression of ERS related factors,with statistically significant differences(P < 0.05).Conclusion ERS is involved in hcy-mediated apoptosis of myocardial cells,and LBP can alleviate ERS to achieve myocardial protection.