Objective: To explore the effect of calcium-independent phospholipase A2 (iPLA2) on the expression of mitochondrial glycerol 3-phosphate dehydrogenase (mGPDH) in human non-alcoholic fatty liver disease cells. Methods: Oleic acid was used to construct a non-alcoholic fatty liver disease cell model by inducing lipid deposition in THLE-2 cells in vitro. Simultaneously, intracellular triglyceride content, iPLA2 expression levels, and mGPDH levels were determined at various induction times (0, 24, 48, and 72 h) using a triglyceride assay kit, quantitative RT-PCR, and western blotting. The model cells were treated with bromelenol lactone, an iPLA2 inhibitor, and N-acetylcysteine, a ROS inhibitor, respectively. Following continuous culture for 24 and 48 hours, the cells were harvested, and the mRNA and protein expression levels of mGPDH were measured. Statistical analysis was performed using the t-test, one-way analysis of variance, and linear correlation. Results: The intracellular triglyceride content gradually increased (P < 0.01), the mGPDH mRNA and protein expression decreased (P < 0.01), and the iPLA2 mRNA and protein expression increased (P < 0.01) in THLE-2 cells with the prolonging time effect of oleic acid therapy. In addition, the mGPDH mRNA expression level was negatively correlated with the iPLA2 mRNA level (r = -0.878, P = 0.002). The expression levels of mGPDH mRNA and protein in the iPLA2 inhibitor group and ROS inhibitor group were increased compared with the model control group (P < 0.01). The expression of mGPDH mRNA was increased at 24 h compared with 48 h in the iPLA2 inhibitor group (P < 0.01). The expression of mGPDH mRNA was gradually increased in the ROS inhibitor group with the prolongation of inhibitor action time (P < 0.01). Compared with the two inhibitor groups, the increase in mGPDH mRNA was significantly higher in the ROS inhibitor group than that in the iPLA2 inhibitor group, and the difference was statistically significant (P < 0.01). Conclusion: iPLA2 can inhibit the expression of mGPDH in non-alcoholic fatty liver cells to a certain extent.
目的： 探讨钙非依赖性磷脂酶A2（iPLA2）在人非酒精性脂肪性肝病细胞中对线粒体甘油3-磷酸脱氢酶（mGPDH）表达的影响。 方法： 体外用油酸诱导THLE-2细胞脂质沉积，构建非酒精性脂肪性肝病细胞模型。同时运用甘油三酯试剂盒、定量RT-PCR和蛋白质印迹法分别检测不同诱导时期（0、24、48、72 h）细胞内甘油三酯含量、iPLA2及mGPDH的表达水平。在模型细胞中分别加入iPLA2抑制剂溴烯醇内酯和活性氧（ROS）抑制剂N-乙酰半胱氨酸，继续培养24、48 h后收集细胞，检测细胞内mGPDH的mRNA和蛋白的表达水平。采用t检验、单因素方差分析、直线相关分析法进行统计学分析。 结果： 随着油酸作用THLE-2细胞时间的延长，细胞内甘油三酯含量逐渐增加（P < 0.01），mGPDH mRNA及蛋白表达量降低（P < 0.01），iPLA2 mRNA及蛋白表达量增加（P < 0.01）。并且mGPDH mRNA表达水平与iPLA2 mRNA水平呈负相关（r = -0.878，P = 0.002）。iPLA2抑制剂组和ROS抑制剂组中mGPDH mRNA和蛋白表达量较模型对照组增加（P值均< 0.01）。iPLA2抑制剂组中24 h mGPDH mRNA表达量较48 h增加（P < 0.01）。ROS抑制剂组中mGPDH mRNA表达量随抑制剂作用时间的延长而逐渐增加(P < 0.01)。2个抑制剂组比较，ROS抑制剂组mGPDH mRNA增加较iPLA2抑制剂组明显，差异有统计学意义（P < 0.01）。 结论： 非酒精性脂肪性肝病细胞中iPLA2在一定程度上可抑制mGPDH的表达。.
Keywords: Calcium-independent phospholipase A2; Glycerol 3-phosphate dehydrogenase; Non-alcoholic fatty liver disease; Non-alcoholic fatty liver disease cells.