| 摘要: |
| 目的 观察大麻二酚（CBD）对棕榈酸（PA）诱导的肝细胞损伤的保护作用，并考察其与自噬流相关的潜在机制。方法 原代培养大鼠肝细胞，分别给予1 μmol/L和5 μmol/L的CBD处理24 h，采用蛋白质印迹法检测自噬相关蛋白微管相关蛋白1轻链3（LC3）和p62的表达，考察CBD对细胞自噬的影响。将细胞分为4组并分别给予不同处理：PA组（800 μmol/L PA处理细胞）、PA+CBD组（800 μmol/L PA和5 μmol/L CBD联合作用）、PA+CBD+CQ组[800 μmol/L PA、5 μmol/L CBD和50 nmol/L自噬抑制剂氯喹（CQ）共同作用]和阴性对照组（加入等体积0.03% DMSO处理细胞），每组作用时间均为24 h；采用蛋白质印迹法检测LC3和p62的蛋白表达，流式细胞术考察细胞凋亡情况，qPCR法检测内质网应激相关因子CCAAT/增强子结合蛋白同源蛋白（CHOP）、葡萄糖调节蛋白78（GRP78）和X盒结合蛋白1（XBP-1） mRNA的表达，Rh123和lucigenin荧光探针分别检测线粒体的膜电位和活性氧簇（ROS）含量。结果 1 μmol/L和5 μmol/L CBD均不影响肝细胞LC3-Ⅱ/LC3-Ⅰ的比值以及p62蛋白的表达。与阴性对照组相比，PA组肝细胞LC3-Ⅱ/LC3-Ⅰ的比值和p62蛋白表达增加（P<0.05），细胞凋亡增加（P<0.05），CHOP、GRP78、XBP-1 mRNA表达增加（P<0.05），线粒体膜电位降低（P<0.05），线粒体ROS的生成增加（P<0.05）；与PA组相比，PA+CBD组肝细胞内的自噬流恢复，细胞凋亡减少，内质网应激和线粒体失常减轻（P<0.05）；同时给予CQ处理可以逆转CBD的保护作用（P<0.05）。结论 CBD能够通过促进自噬流减轻PA诱导的肝细胞损伤，改善内质网应激和线粒体功能。 |
| 关键词: 肝细胞 大麻二酚 棕榈酸 自噬流 内质网应激 线粒体功能障碍 细胞凋亡 |
| DOI：10.16781/j.0258-879x.2017.05.0583 |
| 投稿时间：2016-12-02修订日期：2017-02-21 |
| 基金项目:国家自然科学基金（81470900，31100639），上海市自然科学基金（11ZR1448100）. |
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| Cannabidiol attenuates palmitic acid-induced hepatocytes injury through promoting autophagic flux |
| CHEN Rui,GAO Xiao-gang,ZHANG Lei,SHI Xiao-min,GUO Wen-yuan,FU Zhi-ren* |
(Department of Organ Transplantation, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China
*Corresponding author) |
| Abstract: |
| Objective To explore the protective effect of cannabidiol (CBD) on palmitic acid (PA)-induced hepatocytes injury and to investigate the underlying mechanism associated with autophagic flux. Methods Primary cultured rat hepatocytes were treated with 1 or 5 μmol/L CBD for 24 h and Western blotting was performed to detect autophagy-related protein microtubule-associated protein 1 light chain 3 (LC3) and p62 expressions. Then the hepatocytes were divided into 4 groups and received different interventions, including PA group (the hepatocytes were stimulated with 800 μmol/L PA), PA+CBD group (the hepatocytes were co-stimulated with 800 μmol/L PA and 5 μmol/L CBD), PA+CBD+CQ group (the hepatocytes were co-stimulated with 800 μmol/L PA, 5 μmol/L CBD and 50 nmol/L autophagy inhibitor chloroquine[CQ]) and negative control group (an equal volume of 0.03% DMSO was added to the culture medium); the hepatocytes in all groups were treated for 24 h. We used Western blotting to detect LC3 and p62 proteins expressions, flow cytometry to determine apoptosis, qPCR assay to detect the mRNA expressions of CCAAT/enhancer-binding protein homologous protein (CHOP), glucose-regulated protein 78 (GRP78) and X-box-binding protein 1 (XBP-1), and the Rh123 and lucigenin fluorescent probes to detect the mitochondrial membrane potential and reactive oxygen species (ROS) content, respectively. Results The ratio of LC3-Ⅱ to LC3-Ⅰand p62 protein expression had no change in the cultured rat hepatocytes treated with 1 or 5 μmol/L CBD. Compared with the negative control group, the ratio of LC-Ⅱ to LC3-Ⅰand p62 protein expression were significantly increased (P<0.05), the apoptosis was significantly risen (P<0.05), the mRNA expressions of CHOP, GRP78 and XBP-1 were significantly increased (P<0.05), mitochondrial membrane potential was significantly decreased (P<0.05), and the ROS content in mitochondrial was significantly increased (P<0.05) in the PA group. Compared with PA group, the hepatocytes in the PA+CBD group showed an improved autophagic flux, increased apoptosis, reduced endoplasmic reticulum stress and mitochondrial dysfunction (all P<0.05). The protective effect of CBD on PA-induced hepatocytes injury was significantly inhibited by co-incubation with CQ (P<0.05). Conclusion CBD can attenuate PA-induced hepatocytes injury through promoting autophagic flux, reducing hepatocyte apoptosis, and improving endoplasmic reticulum stress and mitochondrial dysfunction. |
| Key words: hepatocytes cannabidiol palmitic acid autophagic flux endoplasmic reticulum stress mitochondrial dysfunction apoptosis |
