【摘要】 目的探讨姜黄素对Aβ_1-42诱导的细胞损伤和凋亡的抑制作用。方法采用体外培养的人神经母细胞瘤SH-SY5Y细胞,分为溶剂对照组、Aβ_1-4210μmol·L^-1损伤组、Aβ_1-4210μmol·L^-1+姜黄素1,5和10μmol·L^-1保护组及姜黄素10μmol·L^-1对照组;噻唑蓝（MTT）法测定细胞存活率,酶活性法检测细胞培养液中乳酸脱氢酶（LDH）的含量以考察细胞损伤程度;AnnexinⅤ-FITC/PI染色法测定细胞凋亡;JC-1染色法检测线粒体膜电位变化;比色法测定胱天蛋白酶9和胱天蛋白酶3的活性;Western蛋白印迹法检测胱天蛋白酶3表达。结果与溶剂对照组比,Aβ_1-4210μmol·L^-1损伤组细胞存活率显著降低（P<0.01）。与Aβ_1-4210μmol·L^-1损伤组比较,姜黄素5和10μmol·L^-1缓解了Aβ_1-42诱导的细胞存活率下降（P<0.05）,降低了Aβ_1-42诱导的乳酸脱氢酶释放水平（P<0.01）和细胞早期及晚期凋亡率（P<0.01）。姜黄素抑制了Aβ_1-42诱导的细胞线粒体膜电位去极化作用（P<0.01）;姜黄素1¹0μmol·L^-1抑制了Aβ_1-42诱导的胱天蛋白酶9及胱天蛋白酶3级联激活作用,且呈浓度依赖性（r=0.990,P<0.01;r=0.996,P<0.01）。姜黄素10μmol·L^-1对照组以上指标与溶剂对照组无明显差异。结论姜黄素可能通过升高线粒体膜电位、降低胱天蛋白酶活性抑制Aβ_1-42诱导的细胞损伤和线粒体途径细胞凋亡。更多还原

【Abstract】 OBJECTIVE To investigate the protective effect of curcumin on Aβ_1-42 damaged cells.METHODS SH-SY5Y cells were cultured with Aβ_1-4210 μmol·L^-1in the absence or presence of curcumin1, 5 or 10 μmol·L^-1.Cell viability was assayed by MTT.Cell membrane damage was detected by the concentration of lactate dehydrogenase（LDH） in culture medium.Cell apoptosis was measured by flow cytometry with Annexin Ⅴ-FITC/PI staining.Mitochondrial membrane potential was characterized by fluorescence of JC-1 dye.Enzymatic activity of caspases-9 and-3 was measured by colorimetric assay.Protein expression of caspase-3 was detected by Western blotting.RESULTS Compared with vehicle control, the cell viability, concentration of LDH and both early and late apoptosis in Aβ_1-4210 μmol·L^-1damaged group were decreased（P<0.01）.However, the cell viability, release of LDH and both early and late apoptosis in curcumin group were promoted compared with that in Aβ_1-4210 μmol·L^-1damaged group.Curcumin inhibited Aβ_1-42-induced depolarization of mitochondrial membrane potential（P<0.01）,and attenuated Aβ_1-42-induced activation of both caspases9 and caspases3 in a concentration-dependent manner, respectively（r=0.990, P<0.01; r=0.996, P<0.01）.There were no significant differences in the above detected indexes between curcumin 10 μmol·L^-1group and vehicle control group.CONCLUSION Curcumin inhibits Aβ_1-42-induced cel damage and apoptosis by promoting mitochondrial membrane potential and depressing the activation of caspases.更多还原