基于Nrf2信号通路的三七总皂苷对Aβ25-35诱导PC12细胞凋亡的保护作用机制研究

摘要

目的：探讨三七总皂苷对Aβ25-35诱导的PC12细胞凋亡的保护作用及分子机制。方法利用 Aβ25-35诱导 PC12细胞损伤模型, MTT 法检测 PC12细胞活力,试剂盒测定LDH漏出量、ROS水平、MDA含量、Caspase-3活力以及抗氧化酶SOD、CAT和GHS-Px活力,TUNEL染色检测细胞凋亡, JC-1染色观察线粒体膜电位, Western blot 检测相关蛋白HO-1、Lamin-B、细胞核内Nrf2及总Nrf2的蛋白表达。结果三七总皂苷能够明显抑制Aβ25-35诱导的PC12细胞活力下降(P<0．01)和LDH漏出(P<0．01),减少ROS和MDA的产生( P <0．01),增加 SOD、CAT 和 GSH-Px 活力( P <0．01),稳定线粒体膜电位,抑制 caspase-3的活化( P <0．01)。而且,三七总皂苷还能够上调 PC12细胞细胞核Nrf2、总Nrf2和细胞质中 HO-1的蛋白表达。 HO-1抑制剂SnPP能够抑制三七总皂苷的神经保护作用。结论三七总皂苷可能通过上调Nrf2/HO-1信号通路,从而抑制 Aβ25-35诱导PC12细胞氧化应激和凋亡。%Aim To investigate the protective effect of Panax Notoginseng Saponins ( PNS ) on Aβ25-35-in-duced apoptosis in PC12 cells and molecular mecha-nism. Methods The cell viability of PC12 cells was detected by MTT assay. The levels of LDH leakage, ROS,MDA,Caspase-3 activity and antioxidant enzyme activities of SOD, CAT, and GSH-Px activity were de-termined by respective kits. The apoptosis of cells was decteced by Western blot. Results PNS could signifi-cantly inhibit the decrease of cell viability and LDH leakage, reduce the production of MDA and ROS( P<0. 01), increase the activity of SOD,CAT and GSH-Px ( P <0. 01 ) , and the mitochondrial membrane poten-tial, inhibit the activation of caspase-3 ( P <0. 01 ) in PC12 cells which were induced by Aβ25-35 . PNS could incrase nuclear Nrf2 and up-regulate HO-1 . The neu-roprotective of PNS could be inhibited by HO-1 inhibi-tor ZnPP. Conclusion PNS may inhibit Aβ25-35-in-duced oxidative stress and apoptosis in PC12 cells by activating Nrf2/HO-1 signaling pathway.