Oxidized high-density lipoprotein promotes rat ovarian granulosa cell apoptosis through reactive oxygen species-initiated p38 signaling pathway / 中国组织工程研究

ABSTRACT

BACKGROUND:Oxidative modification of high-density lipoprotein occurs in patients with polycystic ovary syndrome.However,the relationship between oxidized high-density lipoprotein and ovulation dysfunction and its mechanism are unknown. OBJECTIVE:To investigate the effect and potential mechanism of oxidized high-density lipoprotein on ovarian granulosa cell apoptosis. METHODS:Polycystic ovary syndrome rat model was established,then the high-density lipoprotein was harvested from the rat serum of heart blood.The degree of oxidation of the high-density lipoprotein was detected by high-density lipoprotein inflammation index assay,malondialdehyde assay and lipoprotein agarose gel electrophoresis assay.The normal rat ovarian granulosa cells were isolated and treated with high-density lipoprotein and oxidized high-density lipoprotein isolated from the model rat serum.Cell viability was detected by CCK-8 assay.Cell apoptosis was detected by flow cytometry.The generation of reactive oxygen species was detected by H2DCF-DA staining.The p38 signaling activity was detected by western blot assay.Ovarian granulosa cells were pretreated with reactive oxygen species inhibitors N-acetylcysteine,tetramethylpiperidine(Tempol)and p38 inhibitor SB203580,and then treated with oxidized high-density lipoprotein.Finally,cell apoptosis,reactive oxygen species production and p38 signaling activity were detected. RESULTS AND CONCLUSION:A portion of the high-density lipoprotein from the serum of polycystic ovary syndrome model rats affected oxidative modification.High-density lipoprotein and oxidized high-density lipoprotein isolated from the model rat serum inhibited granulosa cell viability and promoted apoptosis(all P<0.05).They promoted rat granulosa cell reactive oxygen species production and p38 activation(all P<0.05).N-acetylcysteine,Tempol and SB203580 reversed oxidized high-density lipoprotein induced granulosa cell apoptosis(all P<0.05).N-acetylcysteine and Tempol suppressed oxidized high-density lipoprotein-induced p38 activation(all P<0.05).SB203580 did not have a regulatory effect on reactive oxygen species production(P>0.05).In summary,polycystic ovary syndrome can promote partial oxidative modification of high-density lipoprotein.The oxidized high-density lipoprotein promotes rat granulosa cell apoptosis by the activation of the reactive oxygen species-initiated p38 signaling pathway.