紫外线对人晶状体上皮细胞凋亡的诱导及Bcl-2,Bax基因的影响

目的:研究紫外线照射体外培养人晶状体上皮细胞(human lens epithelial cell,HLEC)对凋亡的诱导、凋亡调控基因(Bax,Bcl-2)表达的变化,探讨紫外线诱导HLEC凋亡的机制。方法:以实验室培养的HLEC细胞株为研究模型,采用同一紫外线光源对HLEC进行照射。按紫外线照射时间将HLEC分为0,5,10,15及30 min组。采用Annexin V+PI双染流式细胞计数对HLEC凋亡进行检测,用原位杂交的方法检测各组Bax,Bcl-2 mRNA的表达。结果:随紫外线照射时间的延长HLEC凋亡率增加,Bcl-2阳性细胞率逐渐降低;而Bax阳性细胞率逐渐增加。HLEC凋亡率与Bcl-2和Bax的比率呈负相关(r=-0.874,P<0.05)。结论:紫外线照射可诱导HLEC凋亡,Bax和Bcl-2可能参与了紫外线诱导的HLEC凋亡的基因调控过程。

Ultraviolet radiation-induced apoptosis in human lens epithelial cells and its effect on Bcl-2 and Bax

Objective: To explore the apoptosis-inducing effect of ultraviolet(UV) radiation on human lens epithelial cells(HLEC),with particular focus on changes in Bcl-2 or Bax expression as possible mechanisms. Methods: All experimental groups were exposed to the same UV light source.HLEC were divided into 6 groups according to duration of UV radiation : 0 min group(control group),5 min group,10 min group,15 min group,and 30 min group.Analysis on apoptosis of HLEC was performed by flow cytometry analysis(FCA,Annexin V + PI staining).Changes of Bax and Bcl-2 expression in HLEC were detected by hybridization in situ. Results: Apoptosis in HLEC increased with UV exposure time.The expression level of Bax mRNA was increased with the increase of UV exposure time,whereas the expression level of Bcl-2 mRNA decreased with the increase of UV exposure time.The proportion of apoptotic cells was negatively correlated with ratio of Bcl-2/Bax(r=-0.874,P<0.05). Conclusion: UA radiation can induce apoptosis of HLEC in vitro.Bcl-2 and Bax genes may play an important role in regulating this apoptotic process.