摘要目的:观察竹荪多糖（DIP）对亚砷酸钠（NaAsO 2）诱导人肝细胞（L-02细胞）中PINK1/Parkin途径介导的线粒体自噬的干预作用。 方法:将处于对数生长期且状态良好的L-02细胞分为对照组、NaAsO 2组（10 μmol/L）、DIP组（80 μg/ml）、DIP + NaAsO 2组（80 μg/ml DIP + 10 μmol/L NaAsO 2）、活性氧（ROS）清除剂N-乙酰半胱氨酸（NAC）组（5 mmol/L）、NAC + NaAsO 2组（5 mmol/L NAC + 10 μmol/L NaAsO 2）。蛋白免疫印迹法（Western blot）检测线粒体自噬相关蛋白p62、微管相关蛋白1轻链3（LC3）Ⅱ/LC3Ⅰ、PINK1、Parkin的表达水平，透射电子显微镜观察线粒体结构及自噬体，荧光探针法检测细胞内ROS水平。 结果:与对照组比较，NaAsO 2组p62、LC3Ⅱ/LC3Ⅰ、PINK1、Parkin蛋白表达量均较高（ P均< 0.05）；与NaAsO 2组比较，DIP、DIP + NaAsO 2、NAC、NAC + NaAsO 2组p62、LC3Ⅱ/LC3Ⅰ、PINK1、Parkin蛋白表达量均较低（ P均< 0.05）。透射电子显微镜下，与对照组比较，NaAsO 2组L-02细胞线粒体损伤明显，自噬小体数量增多；与NaAsO 2组比较，DIP + NaAsO 2组线粒体肿胀程度减小，空泡变性减少，自噬小体数量减少。与对照组（33 110.00 ± 2 191.28）比较，NaAsO 2组细胞内ROS水平较高（48 000.00 ± 2 395.31， P < 0.05）；DIP + NaAsO 2组细胞内ROS水平（38 670.00 ± 2 620.56）与NaAsO 2组比较明显降低（ P < 0.05），与对照组比较未见明显改变（ P > 0.05）。 结论:NaAsO 2可以诱导L-02细胞内PINK1/Parkin途径介导的线粒体自噬发生，DIP可以缓解NaAsO 2诱导的线粒体自噬。DIP可能通过对ROS的调控来影响NaAsO 2诱导的PINK1/Parkin途径介导的线粒体自噬。

abstractsObjective:To observe the effect of dictyophora polysaccharide (DIP) on PINK1/Parkin pathway mediated mitophagy induced by sodium arsenite (NaAsO 2) in human hepatocytes (L-02 cells). Methods:The L-02 cells in logarithmic growth phase and in good condition were divided into control group, NaAsO 2 group (10 μmol/L), DIP group (80 μg/ml), DIP + NaAsO 2 group (80 μg/ml DIP + 10 μmol/L NaAsO 2) , N-acetylcysteine (NAC) group (5 mmol/L), and NAC + NaAsO 2 group (5 mmol/L NAC + 10 μmol/L NaAsO 2). Western blotting was used to detect the expression levels of mitophagy related proteins p62, microtubule-associated protein 1 light chain 3 (LC3)Ⅱ/LC3Ⅰ, PINK1, and Parkin. The mitochondrial stucture and autophagosomes were observed by transmission electron microscope, the fluorescent probe method was used to detect the expression level of intracellular reactive oxygen species (ROS). Results:Compared with the control group, the protein expressions of p62, LC3 Ⅱ/LC3 Ⅰ, PINK1, and Parkin in NaAsO 2 group were higher ( P < 0.05); compared with the NaAsO 2 group, the protein expressions of p62, LC3 Ⅱ/LC3 Ⅰ, PINK1 and Parkin were lower in DIP, DIP + NaAsO 2, NAC, and NAC + NaAsO 2 groups ( P <0.05). According to the transmission electron microscope, compared with the control group, the mitochondria of L-02 cells in NaAsO 2 group were significantly damaged and the number of autophagosomes increased. Compared with NaAsO 2 group, the degree of mitochondrial swelling, vacuolar degeneration and the number of autophagosomes decreased in DIP + NaAsO 2 group. Compared with the control group (33 110.00 ± 2 191.28), the intracellular ROS level in NaAsO 2 group was higher (48 000.00 ± 2 395.31, P < 0.05); the level of intracellular ROS in DIP + NaAsO 2 group (38 670.00 ± 2 620.56) was significantly lower than that in NaAsO 2 group( P < 0.05), and there was no significant change compared with the control group ( P > 0.05). Conclusions:NaAsO 2 can induce PINK1/Parkin mediated mitophagy in L-02 cells. DIP can alleviate NaAsO 2 induced mitophagy. DIP may affect PINK1/Parkin mediated mitophagy induced by NaAsO 2 through the regulation of ROS.