三七总皂苷通过AMPK通路对PASMCs自噬的影响

Effects of Panax Notoginseng Total Saponins on PASMCs Autophagy through AMPK Pathway

该文探讨了在低氧高二氧化碳条件下,三七总皂苷对大鼠肺动脉平滑肌细胞(PASMCs)自噬的调控机制及对PASMCs增殖、凋亡的干预。以大鼠PASMCs为研究对象,饥饿处理后将其随机分为五组:正常对照组(N)、模型组(HH)、AMPK激动剂AICAR组(AI)、三七总皂苷组(PNS)和三七总皂苷联合AMPK激动剂组(PA)五组。相应处理后用CCK-8法检测各组细胞存活率;qRT-PCR法检测AMPK、mTOR、LC3、p62、Caspase-3的mRNA表达水平,Western blot检测AMPK、p-AMPK、mTOR、p-mTOR、LC3、p62、Caspase-3、PCNA的蛋白表达水平。透射电镜观察自噬小体。结果显示,与HH组相比,PNS组Caspase-3表达上调,PCNA表达下调,提示PNS可以促进PASMCs凋亡,抑制其增殖;PNS组AMPK-mTOR信号通路下调,自噬水平下降,说明PNS可以下调AMPK-mTOR通路活性,抑制自噬;PA组与PNS组相比自噬水平上升,增殖上调,凋亡减少,提示PNS对低氧高二氧化碳环境引起的大鼠PASMCs增殖的抑制作用可能是通过下调AMPK-mTOR信号通路抑制自噬,促进凋亡发挥作用的。

This study investigated the regulation mechanism of Panax notoginseng total saponins on autophagy of rat PASMCs(pulmonary artery smooth muscle cells)and the intervention on PASMCs proliferation and apoptosis under hypoxia and high carbon dioxide conditions.The rat PASMCs were randomly divided into five groups after starvation treatment:normal control group(N),model group(HH),AMPK agonist AICAR group(AI),Panax notoginseng total saponins group(PNS)and Panax notoginseng total saponins combined with AMPK agonist group(PA).After corresponding treatment,cell survival rate of each group was measured by CCK-8.AMPK,mTOR,LC3,p62 and Caspase-3 were detected by qRT-PCR,and the protein expression levels of AMPK,p-AMPK,mTOR,p-mTOR,LC3,p62,Caspase-3 and PCNA were detected by Western blot.Autophagosomes were observed by transmission electron microscopy.The results showed that compared with HH group,the expression of Caspase-3 was up-regulated and the expression of PCNA was down-regulated in PNS group,suggesting that PNS could promote the apoptosis of PASMCs and inhibit its proliferation.In the PNS group,AMPK-mTOR signaling pathway was down-regulated and autophagy level decreased,indicating that PNS could down-regulate AMPK-mTOR pathway activity and inhibit autophagy level.Compared with PNS group,the level of autophagy in PA group was increased,the proliferation was up-regulated,and the apoptosis was decreased,suggesting that PNS might inhibit the proliferation of PASMCs induced by hypoxia and high carbon dioxide in rats by down-regulating AMPK-mTOR signaling pathway to inhibit autophagy and promote apoptosis.