苓桂术甘汤调控PINK1/Parkin通路改善线粒体自噬对非酒精性脂肪肝炎小鼠的影响

Effect of Linggui Zhugan Decoction in regulating PINK1/Parkin pathway to improve mitophagy in the NASH mice

关键词:  苓桂术甘汤  非酒精性脂肪肝炎  线粒体自噬  氧化应激  PINK1/Parkin通路

Key words:  Linggui Zhugan Decoction  non-alcoholic steatohepatitis  mitochondrial autophagy  oxidative stress  PINK1/Parkin pathway

摘要:

[目的] 研究苓桂术甘汤（LGZG）对非酒精性脂肪肝炎（NASH）模型小鼠的治疗效果及对PTEN诱导推定激酶1（PINK1）/泛素蛋白连接酶（Parkin）信号通路的影响。[方法] 通过蛋氨酸和胆碱缺乏（MCD）饮食诱导建立NASH小鼠模型，并灌胃不同剂量的LGZG。通过检测各组小鼠体质量、肝指数、丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、三酰甘油（TG）、总胆固醇（TC）、肝组织苏木精-伊红（HE）染色及冰冻组织油红O染色评估LGZG对NASH模型小鼠的治疗作用；通过对超氧化物歧化酶（SOD）、丙二醛（MDA）、谷胱甘肽过氧化物酶（GSHPx）、活性氧（ROS）的检测来评估LGZG对NASH模型肝脏抗氧化的能力；通过检测线粒体标志物TOM20、细胞色素c氧化酶Ⅳ亚型（COXⅣ）、电压依赖性阴离子通道蛋白1（VDAC1）的蛋白水平进而评估PINK1/Parkin通路的关键蛋白PINK1、Parkin、微管相关蛋白1轻链3-Ⅱ（LC3-Ⅱ）、P62、Beclin1的水平来探究LGZG对线粒体自噬的影响。[结果] LGZG可明显提升NASH模型小鼠体质量；降低肝指数；降低血清ALT、AST活性；降低TC、TG水平；同时改善NASH模型小鼠肝组织病理学变化，提示LGZG对NASH模型小鼠具有治疗作用；提高了SOD和GSH-Px水平的同时降低了MDA和ROS水平，提示LGZG提高了肝脏抗氧化能力。提高了PINK1、Parkin、LC3-Ⅱ、beclin1蛋白水平同时降低了TOM20、COXⅣ、VDAC1、P62蛋白水平，说明LGZG改善了NASH小鼠由PINK1/Parkin介导的线粒体自噬。[结论] LGZG对NASH模型小鼠具有治疗作用，并且提高肝脏抗氧化能力，其作用机制可能与通过调控PINK1/Parkin信号通路来改善线粒体自噬有关。

Abstract:

[Objective]To investigate the therapeutic effect of Linggui Zhugan Decoction (LGZG) on non-alcoholic steatohepatitis (NASH) model mice and its impact on the PINK1/Parkin signaling pathway.[Methods]A NASH mouse model was established using a methionine- and choline-deficient (MCD) diet, followed by intragastric administration of different doses of LGZG. The therapeutic effect of LGZG on NASH model mice was assessed by measuring body weight, liver index, serum ALT, AST, TG, and TC levels, as well as by performing hematoxylin-eosin (HE) staining and Oil Red O staining on frozen liver tissues. The liver's antioxidant capacity was evaluated by detecting levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and reactive oxygen species (ROS). To explore the effect of LGZG on mitophagy, the protein levels of mitochondrial markers (TOM20, COXⅣ, VDAC1) and key proteins of the PINK1/Parkin pathway (PINK1, Parkin, LC3-Ⅱ, P62, Beclin1) were measured.[Results]LGZG significantly increased the body weight of NASH model mice; reduced the liver index; decreased serum ALT and AST activities; lowered TC and TG levels; and ameliorated pathological changes in the liver tissue of NASH model mice. These results indicate that LGZG has a therapeutic effect on NASH model mice. LGZG increased SOD and GSH-Px levels while decreasing MDA and ROS levels, suggesting enhanced hepatic antioxidant capacity. Furthermore, LGZG increased the protein levels of PINK1, Parkin, LC3-Ⅱ, and Beclin1, while decreasing the protein levels of TOM20, COXⅣ, VDAC1, and P62. This demonstrates that LGZG improved PINK1/Parkin-mediated mitophagy in NASH mice.[Conclusion]LGZG exhibits a therapeutic effect on NASH model mice and enhances hepatic antioxidant capacity. The underlying mechanism may be associated with the regulation of the PINK1/Parkin signaling pathway to improve mitophagy.