Mechanism Of Exogenous Cholesterol Regulation Of Vigilin/ER? Promoting Granulose Cell Apoptosis

Background:In recent years,a large number of studies had found that imbalances in energy metabolism,such as hypercholesterolemia,can seriously affect the human reproductive system.During the development of follicles,a large number of germ cells are consumed due to the atresia of follicles.Studies had shown that follicular atresia is caused by granulosa cell apoptosis.Granular cells exist in various stages of follicular development,which not only provide nutrition for oocytes,but also participate in the occurrence of eggs and the maturation of eggs,so that granulosa cells are crucial for the development of follicles.Polycystic ovary syndrome is a kind of disease caused by endocrine and metabolic disorders common in women of childbearing age.It has the characteristics of polycystic ovary,hyperandrogenism,insulin resistance,anovulation and metabolic abnormalities.With the research progress in the field of energy metabolism and reproduction,it is found that lipid metabolism disorder can seriously affect the human reproductive system,and further realize that the accumulation of egg nutrients will seriously affect the quality of eggs.Lipid metabolism and granulosa cells are important for the development of follicles.Therefore,this study aimed to investigate the effect of exogenous cholesterol on the apoptosis of KGN cells?human ovarian granulosa cell tumor?and its mechanism,and provide a new target for further elucidation of the pathogenesis and prevention of follicular dysplasia.Methods:1.KGN cells were cultured in a DMEM high glucose medium containing 10%calf serum at 37°C 5%CO ₂ incubator.2.KGN cells were treated with exogenous cholesterol at different concentrations?0?g/ml,5?g/ml,10?g/ml,20?g/ml?for 24 h.Oil red O staining was used to observe intracellular lipid content,and NBD-Cholesterol fluorescent label showed the content of cholesterol.3.After exogenous cholesterol treatment,the effects of different concentrations of exogenous cholesterol on the apoptosis status of KGN cells were examined.4.MTT was used to detect the effect of different concentrations of exogenous cholesterol on the proliferation of KGN cells.Western blot and qRT-PCR were used to detect the effects of different concentrations of exogenous cholesterol on the expression of vigilin mRNA,vigilin protein,ER?protein and apoptosis related proteins BAX and BCL-2 in KGN cells.6.Intervene in ER?and observe the apoptosis of KGN cells.Results:1.Exogenous cholesterol was incubated with KGN cells for24 h,which increased the cell body of KGN cells and increased the intracellular lipid content.Compared with the control group,the treated group increased the number of apoptotic cells;BAX expression increased,BCL-2 The expression was decreased,10?g/ml,20?g/ml exogenous cholesterol treatment group was statistically significant?P<0.05?.2.Compared with the control group,the expression of vigilin and ER?in KGN cells was up-regulated,and the difference between 10?g/ml and20?g/ml exogenous cholesterol treatment group was statistically significant?P<0.05?.3.Exogenous cholesterol inhibited the proliferation of KGN cells,10?g/ml,20?g/ml exogenous cholesterol treatment group was statistically significant?P<0.05?.4.After treatment of KGN cells with estrogen receptor ER?inhibitor ICI182780,KGN cell apoptosis decreased.Conclusion:1.Exogenous cholesterol can promote apoptosis of KGN cells and can inhibit proliferation of KGN granulosa cells.2.The vigilin/ER?signaling molecule is involved in the regulation of exogenous cholesterol on KGN cell apoptosis.