摘要
目的:探讨氧化苦参碱干预砷致肝星状细胞(HSC)活化过程中细胞自噬的变化。方法:本实验使用100 μmol/L亚砷酸钠作用于人胎肝细胞株LO2 24 h,收取培养上清。将染砷LO2细胞培养上清与正常培养液按照1 ∶ 4比例混合,用于培养人肝星状细胞株LX-2,24 h后采用低(0.25 g/L)和高(1 g/L)剂量氧化苦参碱干预培养24 h;采用全自动生化分析仪检测染砷LO2细胞培养上清中天冬氨酸氨基转移酶(AST)和丙氨酸氨基转移酶(ALT)水平;ELISA检测染砷LO2细胞培养上清中转化生长因子β1(TGF-β1)水平;MTT法检测LX-2细胞活力;Western blot检测α-平滑肌肌动蛋白(α-SMA)、自噬相关基因12(Atg12)、自噬相关基因5(Atg5)和微管相关蛋白1轻链3-Ⅱ(LC3-Ⅱ)蛋白表达水平变化;油红O染色光镜下观察LX-2细胞中脂滴。结果:(1)染砷LO2细胞培养上清AST和ALT水平显著增加( P <0.05),此上清加入LX-2细胞培养基中可明显增强LX-2细胞活力( P <0.05),与染砷LO2细胞培养上清共孵育的LX-2细胞内脂滴数量显著减少,且LX-2活化标志蛋白α-SMA表达水平显著上调( P <0.05);(2)与染砷LO2细胞培养上清共孵育可上调LX-2细胞Atg12、Atg5和LC3Ⅱ蛋白表达,较对照组差异具有显著性( P <0.05);(3)低、高剂量氧化苦参碱干预可抑制与染砷LO2细胞培养上清共孵育的LX-2细胞的活力( P <0.05),且使LX-2细胞α-SMA、Atg12、Atg5和LC3-Ⅱ蛋白表达水平显著下调( P <0.05),高剂量氧化苦参碱干预的LX-2细胞自噬标志蛋白LC3-Ⅱ表达水平降低较低剂量氧化苦参碱干预更为显著( P <0.05);(4)低、高剂量氧化苦参碱干预后LX-2细胞内脂滴数量较染砷LO2细胞培养上清共孵育的LX-2细胞均显著增多。结论:砷致肝纤维化过程中间接活化HSC与砷损伤肝细胞有关,细胞自噬参与这一过程,且HSC可能通过促进其内脂滴降解而促进自身的活化。氧化苦参碱可通过抑制细胞自噬,减少HSC活化实现其减轻肝纤维化的作用。
AIM: To investigate the effect of oxymatrine (OM) on the autophagy of hepatic stellate cells (HSC) during HSC activation induced by arsenic (As). METHODS: Supernatant of human LO2 hepatocytes cultured with 100 μmol/L NaAsO 2 for 24 h was collected. Human HSC line LX-2 was cultured for 24 h before mingling culture supernatant of LO2 cells with arsenic exposure and normal culture media in a 1∶ 4 ratio, and then treated with low dose (0.25 g/L) and high dose (1 g/L) of OM. The levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in culture medium were measured by biochemical method. The level of transforming growth factor-β1 (TGF-β1) in the culture supernatant of LO2 cells with arsenic exposure was detected by ELISA. The cell viability was examined by MTT assay. The protein levels of α-smooth muscle actin (α-SMA), autophagy-related gene 12 (Atg12), autophagy-related gene 5 (Atg5) and microtubule-associated protein 1 light chain 3-Ⅱ(LC3-Ⅱ) were determined by Western blot. Lipid droplets were observed by oil red O staining under microscope. RESULTS: The levels of AST and ALT were obviously increased in the culture supernatant of LO2 cells with arsenic exposure ( P <0.05). The viability of LX-2 cells was obviously enhanced while adding supernatant of LO2 cells with arsenic exposure into the culture media of LX-2 cells ( P <0.05), the number of lipid drops decreased, and the expression of α-SMA was increased ( P <0.05). Co-incubation with supernatant of LO2 cells and arsenic exposure obviously increased the expression of Atg12, Atg5, LC3-Ⅱ at protein level in the LX-2 cells as compared with control group ( P <0.05). Low dose and high dose of OM inhibited the viability of LX-2 cells caused by co-incubation of the supernatant of LO2 cells with arsenic exposure ( P <0.05) and decreased the protein expression of α-SMA, Atg12, Atg5 and LC3-Ⅱ in the LX-2 cells ( P <0.05). High dose of OM was more effective in expression of LC3-Ⅱ than low dose ( P <0.05). The number of lipid droplets in the LX-2 cells treated with OM was increased obviously as compared with the supernatant of LO2 cells with arsenic exposure. CONCLUSION: Arsenic exposure promotes the activation of HSC by damage of hepatocytes. Autophagy participates in the activation of HSC, and the mechanism is concerned with providing energy by degrading the lipid droplet of HSC. Oxymatrine intervention alleviates liver fibrosis by inhibiting autophagy and activation of HSC.
作者
马子华
张景允
杨柳
田甜
汤雷
郑璐
蔡爽
韩冰
谢汝佳
杨婷
杨勤
MA Zi-hua;ZHANG Jing-yun;YANG Liu;TIAN Tian;TANG Lei;ZHENG Lu;CAI Shuang;HAN Bing;XIE Ru-jia;YANG Ting;YANG Qin(Department of Pathophysiology, Guizhou Provincial Key Laboratory of Pathogensis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang 550000 , China)
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2019年第9期1662-1667,共6页
Chinese Journal of Pathophysiology
基金
国家自然科学基金资助项目(No.81460484)
关键词
肝星状细胞
氧化苦参碱
自噬
细胞活力
肝纤维化
Hepatic stellate cells
Oxymatrine
Autophagy
Cell viability
Hepatic fibrosis
