基于PGC-1α-Sirt3通路探讨九龙藤总黄酮对氧糖剥夺诱导HT22细胞损伤的保护作用

Study on the Protective Effect of Total Flavonoids from Bauhinia Championii (Benth.) Benth. on Oxygenglucose Deprivation-induced HT22 Damage in Mice Based on PGC-1α-Sirt3 Signaling Pathway

目的:基于PGC-1α-Sirt3信号通路探讨九龙藤总黄酮(BCF)对氧糖剥夺(OGD)诱导小鼠海马神经元(HT22)细胞损伤的保护作用。方法:25,50,100,200,400,600μg·ml^-1的BCF预处理HT22细胞24 h后,OGD诱导HT22细胞损伤12 h,MTT法检测HT22细胞存活率,筛选BCF作用OGD诱导HT22细胞的最佳浓度。HT22细胞分为空白对照组、OGD组、OGD+BCF(200μg·ml^-1)组、OGD+BCF(200μg·ml^-1)组+过氧化物酶体增殖物受体γ辅助激活因子-1α(PGC-1α)抑制剂(SR-18292)组、OGD+SR-18292组。TUNEL法检测HT22细胞凋亡,试剂盒检测HT22细胞乳酸脱氢酶(LDH)漏出量、丙二醛(MDA)含量、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性,Rt-PCR和Western Blot分别检测HT22细胞PGC-1α、沉默信息调节因子3(Sirt3)mRNA和蛋白表达。结果:200μg·ml-1的BCF作用OGD诱导的HT22细胞存活率最大。OGD诱导后,HT22细胞凋亡指数、LDH漏出量和MDA含量升高(P<0.05),SOD和GSH-Px活力、PGC-1α和Sirt3 mRNA及蛋白表达均降低(P<0.05)。BCF作用后,OGD诱导的HT22细胞凋亡指数、LDH漏出量和MDA含量降低(P<0.05),SOD和GSH-Px活力、PGC-1α和Sirt3 mRNA及蛋白表达均升高(P<0.05)。而加入PGC-1α抑制剂SR-18292后,BCF对OGD损伤的HT22细胞各项检测指标均无显著影响(P>0.05)。结论:BCF通过激活PGC-1α-Sirt3信号通路发挥对OGD诱导损伤的HT22细胞的保护作用。

Objective:To investigate the protective effect of total flavonoids from Bauhinia championii(Benth.)Benth.(BCF)on oxygen-glucose deprivation(OGD)-induced hippocampal neurons(HT22)damage in mice based on PGC-1α-Sirt3 signaling pathway.Methods:HT22 cells were pretreated with BCF respectively at 25,50,100,200,400 and 600μg·ml-1 for 24 h,and then injured by OGD for 12 h.MTT assay was used to detect the survival rate of HT22 cells to screen the optimal concentration of BCF for induced HT22 cells by OGD.HT22 cells were divided into the blank control group,OGD group,OGD+BCF group,OGD+BCF+peroxisome proliferator-activated receptor-γcoactivator-1α(PGC-1α)inhibitor(SR-18292)group and OGD+SR-18292 group.MTT assay was used to detect the survival rate of OGD-induced HT22 cells and screen the optimal concentration of BCF for OGD-induced HT22 cells.TUNEL assay was used to detect the apoptosis of HT22 cells,the leakages of lactate dehydrogenase(LDH),malondialdehyde(MDA),superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)from HT22 cells were detected by kits,Rt-PCR and Western blot were used to detect the expressions of PGC-1αand SIRT3 mRNAs,and protein expressions in HT22 cells as well.Results:The survival rate of OGD-induced HT22 cells under the action of 200μg·ml^-1 BCF was the highest.After OGD induction,HT22 cell apoptosis index,LDH leakage and MDA content increased(P<0.05),SOD and GSH-Px activities,PGC-1αand Sirt3 mRNAs and protein expressions decreased(P<0.05).After BCF treatment,HT22 cell apoptosis index,LDH leakage and MDA content decreased(P<0.05),SOD and GSH-Px activities,PGC-1αand Sirt3 mRNAs and protein expressions increased(P<0.05).However,after adding SR-18292,BCF had no significant effect on OGD-induced HT22 cells(P>0.05).Conclusion:BCF exhibits protective effects on HT22 cells injured by OGD by activating PGC-1 a-Sirt3 signaling pathway.