雷公藤内酯醇抑制尾加压素-Ⅱ诱导的人晶状体上皮细胞增殖及信号转导机制

The Effect of Triptolide on Proliferation Induced by Urotensin-Ⅱ in Human Lens Epithelial Cell and the Machenism of Signal Transduction

目的探讨雷公藤内酯醇(Triptolide,Tri)抑制尾加压素Ⅱ(UrotensinⅡ,U-Ⅱ)诱导的人晶状体上皮细胞(human lensepithelial cell,HLEC)增殖及cAMP、cGMP信号转导机制。方法将U-Ⅱ诱导体外培养的HLEC发生增殖,并用不同浓度的Tri与其共同孵育后,用四甲基偶氮唑蓝(methyl thiazolyl tetrazolium,MTT)法检测HLEC的活性;用流式细胞术(flow cytometer,FCM)检测HLEC增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)表达;用荧光分光光度法检测HLEC内游离钙离子浓度;用放射免疫分析法检测HLEC内环化腺苷酸(cyclicadenosine monophosphate,cAMP)和环化鸟苷酸(cyclic guanosine monophosphate,cGMP)浓度。结果U-Ⅱ组HLEC活性、PCNA蛋白表达和cGMP浓度均高于对照组(P<0.001);Tri组HLEC活性、PCNA蛋白表达和cGMP浓度均比U-Ⅱ组降低(P<0.001)。U-Ⅱ组HLEC[Ca2+]i比对照组显著升高(P<0.001);Tri组与U-Ⅱ组比较[Ca2+]i也显著升高(P<0.001)。U-Ⅱ组cAMP浓度比对照组显著降低(P<0.001),Tri组cAMP浓度与U-Ⅱ组比较显著升高(P<0.001)。结论Tri可抑制U-Ⅱ诱导的HLEC增殖。[Ca2+]、cAMP-PKA、cGMP-PKG是其重要的细胞信号转导机制。Tri有可能成为防治后发性白内障的有效药物。

Objective：To study the inhibitory effect of Triptolide（Tri）on proliferation induced by urotensin-Ⅱ in human lens epithelial cell （HLEC） and signal transduction mechanism on [Ca~ 2＋ ]i,cAMP and cGMP. Method：The proliferations of cultured HLEC were induced by urotensin-Ⅱ （U-Ⅱ）,which were incubated with different concentrations of Tri. The HLEC activities were detected via methyl thiazolyl tetrazolium （MTT）. The proliferating cell nuclear antigen （PCNA）of HLEC were detected via flow cytometer（FCM）. The concentration of intracellular free calcium （[Ca~ 2＋ ]i） of HLEC were detected with Fura-2/AM by spectrofluoremeter. The intracellular contents of cyclic adenosine monophosphate （cAMP） and cyclic guanosine monophosphate （cGMP） of HLEC were assayed by Radioimmuno assay. Result：The activity,expression of PCNA and the cGMP concentration of HLEC in U-Ⅱ group were higher than that in control group,there were decreased in Tri group significantly （P0.001）. The [Ca~ 2＋ ]i concentration of HLEC in U-Ⅱ group were higher than that in control group,there were increased in Tri group significantly （P0.001）. The cAMP concentration of HLEC in U-Ⅱ group were decreased to compare with control group,but there were increased in Tri group significantly （P0.001）. Conclusion： Tri can inhibit the proliferation of HLEC induced by urotensin-Ⅱ. [Ca~ 2＋ ],cAMP-PKA and cGMP-PKG were the important mechanism of signal transduction. Tri may become an effective drug of preventing and treating after cataract.