北五味子多糖对缺氧/复氧心肌细胞氧化应激损伤的保护作用

Protective Effect of Schisandra Chinensis Polysaccharide on Oxidative Stress Injury in Hypoxia/Reoxygenation Cardiomyocyte

目的观察北五味子多糖(SCP)对缺氧/复氧(H/R)诱导的心肌细胞凋亡及氧化应激损伤的影响及对微小RNA-212-3p(miR-212-3p)/10号染色体上缺失的磷酸酶和张力蛋白同源物(PTEN)分子轴的调控机制。方法体外培养大鼠心肌细胞H9c2,建立H/R损伤模型,分别采用不同剂量SCP处理细胞;采用流式细胞术检测细胞凋亡率;采用酶标法检测乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)、丙二醛(MDA)含量;实时荧光定量聚合酶链反应(RT-qPCR)检测miR-212-3p、PTEN表达量;应用双荧光素酶报告实验验证miR-212-3p、PTEN靶向关系。结果H/R处理后,细胞凋亡率升高(P<0.05),LDH、MDA含量与PTEN表达量升高(P<0.05),SOD含量与miR-212-3p表达量降低(P<0.05);SCP可降低细胞凋亡率与LDH、MDA含量及PTEN表达水平(P<0.05),提高SOD含量及miR-212-3p表达水平(P<0.05);双荧光素酶报告实验证实miR-212-3p可靶向结合PTEN;干扰miR-212-3p表达可减轻SCP对H/R诱导的心肌细胞凋亡及氧化应激损伤的作用。结论SCP可能通过促进miR-212-3p表达,抑制PTEN表达,从而抑制H/R诱导的心肌细胞凋亡,减轻氧化应激损伤。

Objective To investigate the effect of schisandra chinensis polysaccharide(SCP)on hypoxia/reoxygenation(H/R)-induced cardiomyocyte apoptosis and oxidative stress injury and its effect on microRNA-212-3p(miR-212-3p)/chromosome 10 regulatory mechanisms of the missing phosphatase and tensin homolog(PTEN)molecular axis.Methods Rat cardiomyocyte H9c2 were cultured in vitro to establish H/R injury models,and the cells were treated with different doses of SCP.The apoptosis rate was detected by flow cytometry,the contents of lactate dehydrogenase(LDH),superoxide dismutase(SOD),and malondialdehyde(MDA)were detected by enzyme labeling method;real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)to detect the expressions of miR-212-3p and PTEN;dual luciferase reporter assay was used to verify the targeting relationship between miR-212-3p and PTEN.Results After H/R treatment,the apoptosis rate was increased(P<0.05),the contents of LDH and MDA and the expression of PTEN were increased(P<0.05),and the content,of SOD and the expression of miR-212-3p were decreased(P<0.05).SCP to decrease the apoptosis rate,LDH,MDA content,and PTEN(P<0.05),and increase SOD content and miR-212-3p(P<0.05).Dual luciferase reporter assay confirmed that miR-212-3p could target and bind to PTEN,interfering with miR-212-3p to reduce the effect of SCP on H/R-induced cardiomyocyte apoptosis and oxidative stress injury.Conclusion SCP might inhibit H/R-induced cardiomyocyte apoptosis and alleviate oxidative stress injury by promoting the expression of miR-212-3p and inhibiting the expression of PTEN.