丹皮酚抑制帕金森病模型细胞凋亡的作用

目的:观察丹皮酚对帕金森病模型细胞凋亡的影响.方法:采用1-甲基-4-苯基吡啶(MPP+)处理具有多巴胺能神经元特性的PC12细胞建立帕金森病体外模型,并分为正常对照组、空白对照组、1 μmol/L丹皮酚组、3 μmol/L丹皮酚组和9 μmol/L丹皮酚组.以四甲基偶氮唑蓝比色法和乳酸脱氢酶法检测细胞损伤,以赫斯特荧光染剂染色及流式细胞术检测细胞凋亡,以二氯二氢荧光素-乙酰乙酸酯法检测细胞活性氧生成,以蛋白质印迹法检测凋亡相关蛋白半胱氨酸天冬氨酸蛋白酶-3(caspase-3)、Bcl-2和Bcl-2相关X蛋白(Bax)的表达水平.结果:与正常对照组比较,空白对照组细胞存活率显著降低,乳酸脱氢酶漏出率升高,凋亡细胞增多,活性氧生成增加,凋亡相关分子caspase-3活性上调、Bax/Bcl-2比值升高,差异均具有统计学意义(均P <0.01).与空白对照组比较,各浓度丹皮酚预处理后细胞存活率显著升高,乳酸脱氢酶漏出率降低,凋亡细胞减少,并抑制活性氧生成,降低Bax/Bcl-2的比值及caspase-3蛋白水平,差异均具有统计学意义(P <0.05或P <0.01).结论:丹皮酚能抑制帕金森病模型PC12细胞凋亡,其发挥保护作用的机制可能与改善氧化应激、降低Bax/Bcl-2比值、抑制caspase-3活化有关.
Abstract: Objective: To investigate the effects of paeonol on neuron cell model of Parkinson disease (PD). Methods: The cell model of Parkinson disease was induced by treatment of 1-Methyl-4-phenylpyridinium (MPP+) in PC12 cells, the PD model cells were treated with 1 μmol/L, 3 μmol/L or 9 μmol/L paeonol for 24h, respectively. Cell viability and LDH leakage were detected by MTT and lactate dehydrogenase (LDH) assay; the apoptosis of PC12 cells was assessed by Hoechst 33258 staining and flow cytometry; reactive oxygen species (ROS) production was detected by DCFH-DA method; and the ratio of Bax/Bcl-2 and activation of caspase-3 were determined by Western blotting. Results: MPP+ treatment significantly reduced cell viability, increased LDH leakage, enhanced the proportion of apoptotic cells and ROS production. In addition, MPP+ treatment dramatically increased the Bax/Bcl-2 ratio, and the activation of caspase-3. Compared to PD model group, paeonol treatment significantly enhanced cell viability, decreased LDH leakage, inhibited the proportion of apoptotic cells and ROS production, reduced the Bax/Bcl-2 ratio and the activated caspase-3 protein. Conclusion: Paeonol can prevent PC12 cells from apoptosis induced by MPP+, and the mechanism may be associated with the down-regulation of ROS production, Bax/Bcl-2 ratio and Caspase-3 activation. Key words: 1-Methyl-4-phenylpyridinium Parkinson disease Apoptosis/drug effect Paeonol/pharmacology Paeonol/administration & dosage Caspase 3/drug effects bcl-2-associated X protein Genes, bcl-2 Reactive oxygen species