Y-box Binding Protein 1 Regulate Granulosa Cells Apoptosis in Premature Ovarian Insufficiency by Stabilizing Silent Information Regulator 1 mRNA
Objective:To investigate the effects of the Y-box binding protein 1(YBX1)on the proliferation and apoptosis of granulosa cells by regulating silent information regulator 1(SIRT1),and explore the differential ex-pression of YBX1 and SIRT1 of premature ovarian insufficiency(POI)patients and health controls,as well as its clinical significance.Methods:We recruited patients with POI and patients with normal ovarian function during in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI)assisted pregnancy in the Department of Reproduc-tive Medical Center of the Fourth Affiliated Hospital of Jiangsu University from June 2022 to July 2023.The granu-losa cells and serum were collected.Western-Blot(WB)to detect YBX1 protein expression.Real-time quantitative polymerase chain reaction(RT-qPCR)to detect YBX1 and SIRT1 mRNA levels,and the correlation between the abundance of YBX1 and SIRT1 in serum and follicle stimulating hormone(FSH),luteinizing hormone(LH),estra-diol(E2),anti-Mullerian Hormone(AMH),and antral follicle count(AFC)were analyzed.5-bromo-2-deoxyuracil(EdU)and cell counting Kit-8(CCK8)were applied to detect cell proliferation;TdT-mediated dUTP-biotin nick end labeling assay(TUNEL)to detect cell apoptosis;RT-qPCR to detect cell proliferating cell nuclear antigen(PC-NA),B cell lymphoma 2(Bcl2),Bcl2 associated X protein(BAX),and cysteine-aspartate protease 3(Caspase-3)mRNA expression;RNA Immunoprecipitation(RIP)experiment to detect the interaction between YBX1 and SIRT1.Results:The expression of YBX1 protein and SIRT1 mRNA in granulosa cells and serum of POI patients were significantly lower than that of the control group(P<0.05).The expression of YBX1 and SIRT1 mRNA in serum were negatively correlated with FSH,LH(r<0,P<0.05),and positively correlated with E2,AMH and AFC(r>0,P<0.05).Upregulating YBX1 in granulosa cells increased SIRT1 protein expression,SIRT1 mRNA stabili-ty,EdU positive rate,cell viability,PCNA mRNA expression level,Bcl2/BAX ratio(P<0.05),while decreased Caspase-3 mRNA expression level,TUNEL positive rate(P<0.05).Conclusions:The expression levels of YBX1 and SIRT1 in POI patients were significantly reduced and correlated with clinical ovarian function indicators.YBX1 can bind to SIRT1 mRNA and enhance its stability,which may promote the proliferation of granulosa cells,and in-hibit apoptosis.These findings suggested that YBX1 and SIRT1 are expected to become new targets for POI diag-nosis and treatment.
Premature ovarian insufficiencyY-box binding protein 1Silent information regulator 1Granulo-sa cellsCell proliferation and apoptosis