目的 探讨毛蕊花糖苷对棕榈酸处理的HepG2细胞线粒体保护作用，并探讨其作用机制。方法 将HepG2细胞设置为对照组、棕榈酸（100 μmol/L）组、毛蕊花糖苷（50 μmol/L）组、棕榈酸（100 μmol/L）＋毛蕊花糖苷（50 μmol/L）组。MitoSox荧光探针在激光共聚焦显微镜下检测线粒体超氧化物水平的变化；JC-1荧光探针在激光共聚焦显微镜下观察线粒体膜电位的改变；Tomm20、微管相关蛋白轻链3（LC3）特异性抗体进行免疫荧光染色，观察共定位情况；线粒体提取试剂盒提取HepG2细胞内线粒体，蛋白质免疫印迹技术检测线粒体上LC-3Ⅱ蛋白相对表达水平的变化。结果 棕榈酸组细胞内MitoSox红色荧光显著增强（P＜0.05），棕榈酸＋毛蕊花糖苷组HepG2细胞内红色荧光强度显著降低（P＜0.05）；棕榈酸组HepG2细胞内绿/红荧光强度比例显著升高（P＜0.05），棕榈酸＋毛蕊花糖苷组HepG2细胞内绿/红荧光强度比例显著降低（P＜0.05）；Tomm20和LC3共定位分析结果显示，棕榈酸组线粒体与LC3在空间上没有明显的共定位，棕榈酸＋毛蕊花糖苷组HepG2细胞内线粒体形态完整，线粒体与LC3显示出明显的共定位；蛋白质免疫印迹结果显示，与棕榈酸组比较，棕榈酸＋毛蕊花糖苷组HepG2细胞内线粒体上LC3-Ⅱ蛋白相对表达水平显著升高（P＜0.05）。结论 在棕榈酸处理的HepG2细胞模型中，毛蕊花糖苷可能通过诱导线粒体自噬发挥线粒体保护作用。

Objective To investigate the protective effect of acteoside on mitochondria of HepG2 cells treated with palmitic acid, and to explore its mechanism. Methods HepG2 cells were set as the control group, palmitic acid (100 μmol/L) group, acteoside (50 μmol/L) group, and palmitic acid (100 μmol/L) + acteoside (50 μmol/L) group. Changes in mitochondrial superoxide levels were detected by MitoSox fluorescent probes under a laser confocal microscope. The JC-1 fluorescent probe was used to observe the changes of mitochondrial membrane potential under a laser confocal microscope. Immunofluorescence staining was performed with Tomm20 and LC3 specific antibodies to observe the co-localization situation. Mitochondria were extracted from HepG2 cells using the mitochondrial extraction kit, and the changes in the relative expression level of LC-3Ⅱ protein on mitochondria were detected by Western blotting. Results The red fluorescence of MitoSox in the cells of the palmitic acid group was significantly enhanced (P < 0.05), while the intensity of red fluorescence in the cells of HepG2 in the palmitic acid + acteoside group was significantly decreased (P < 0.05). The ratio of intracellular green/red fluorescence intensity in HepG2 cells in the palmitic acid group was significantly increased (P < 0.05), while the ratio of intracellular green/red fluorescence intensity in HepG2 cells in the palmitic acid + acteoside group was significantly decreased (P < 0.05). The results of Tomm20 and LC3 co-localization analysis showed that there was no obvious co-localization of mitochondria and LC3 in space in the palmitic acid group, while the mitochondria morphology in HepG2 cells was intact, and mitochondria and LC3 showed obvious co-localization. The results of Western blotting showed that the relative expression levels of LC3-II protein on mitochondria in HepG2 cells in the palmitic acid + acteoside group were significantly increased compared with those in the palmitic acid group (P < 0.05). Conclusion In HepG2 cells treated with palmitic acid, acteoside may exert mitochondrial protection by inducing mitochondrial autophagy.

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新疆维吾尔自治区自然科学基金资助项目（2022D01B41）；新疆维吾尔医学专科学校自然科学基金重点实验室开放课题项目（SYS2024-002）