白藜芦醇对糖尿病性白内障大鼠晶状体上皮细胞凋亡及bcl-2和bax表达的影响

Effect of resveratrol on lens epithelial cells apoptosis,bcl-2 and bax expression in diabetic rat

目的探讨白藜芦醇对糖尿病性白内障大鼠晶状体上皮细胞(lens epithelialcell,LEC)凋亡及bcl-2和bax表达的影响。方法取90只SpragueDawley大鼠随机分为正常对照组、糖尿病模型组和白藜芦醇治疗组,每组各30只。正常对照组给予常规饲料喂养,模型组大鼠采用链脲佐菌素(60mg.kg-1)诱发糖尿病,白藜芦醇治疗组在模型组基础上按400mg.kg-1体质量给予白藜芦醇灌胃,4周、8周、12周后观察晶状体混浊度的变化情况;同时采用流式细胞术检测LEC凋亡情况,比色法检测caspase-3的活性改变情氉况。并用Western blot检测LECbcl-2和bax蛋白的表达。结果白藜芦醇治疗组12周后,晶状体混浊度Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级、Ⅴ级改变分别为66.7%、23.3%、10.0%、0.0%和0.0%,与模型组(3.3%、20.0%、53.3%、13.3%、10.0%)相比差异有统计学意义(P<0.05)。模型组4周、8周和12周时,LEC凋亡率分别为(8.24±0.88)%、(12.86±1.12)%和(19.87±1.14)%,白藜芦醇处理后,凋亡率明显降低,分别为(5.62±0.56)%、(7.05±1.09)%和(10.53±1.25)%(均为P<0.05)。此外,白藜芦醇对LEC细胞caspase-3的活性也具有一定的抑制作用。bcl-2和bax在正常LEC中均有一定表达,糖尿病模型组bcl-2表达显著降低,bax表达上调,bcl-2/bax比值下降;白藜芦醇治疗组bcl-2/bax比值明显增加。结论白藜芦醇能在一定程度上抑制大鼠LEC凋亡,从而延缓白内障的发生和发展。

Objective To study the effect of resveratrol on lens epithelial cells （LEC） apoptosis, bcl-2 and bax expression in diabetic rats. Methodu Ninety rats were randomly divided into normal control group, diabetic model and resveratrol group, 30 rats in each group. Rats in normal control group were feed by routine diet,diabetic cataract in diabetic model group was induced by 50 mg ~ kg-1 of streptozotocin,and in resveratrol group resveratrol （400 mg ~ kg-1 ） was administrated by gavage on the base of model group. After 4 weeks,8 weeks and 12 weeks ,eyeballs were isolated and lens o- pacity in all rats was recorded. Flow cytometry was used to analyze the lens epithelial cells apoptosis, and the activity of caspase-3 was detected by colorimetry. Expression of bcl-2 and bax were detected by Western blot. Results After treated by resveratrol for 12 weeks,the percentage of lens opacity with grade I to IV was 55.7% ,23.3% ,10.0% , 0 and 0, respectively, there was statistical difference compared with model group （ P 〈 0.05）. The apoptosis rate in model group at 4 weeks, 8 weeks and 12 weeks was （8.24 ＋ 0.88 ） % , （ 12.85 ＋ 1.12 ） % and （ 19.87 ＋ 1.14） % , respectively, and resveratrol could decrease the apoptosis,there was statistical difference（P 〈0.05 ）. In addition, res- veratrol could inhibit the activity of caspase-3. Bcl-2 and bax expressed in normal LEC, but the expression level of bcl-2 was decreased and bax was up-regulated in diabetic model group, accordingly, the ratio of bcl-2/bax was decreased. Resveratrol could in- crease the ratio of bcl-2/bax. Conclusion Resveratrol can inhibit LEC apoptosis to some degree, and thus has the effect on delaying the occurrence and development of di- abetic cataract.