白藜芦醇对糖尿病白内障大鼠正沉默信息调节因子2相关酶1基因表达的影响

Effect of resveratrol on SIRT1 gene expression in lenses of diabetic cataract rat

摘要:

目的  探讨白藜芦醇对糖尿病白内障大鼠晶状体正沉默信息调节因子2相关酶1（SIRT1）基因表达的影响。方法  80只Wistar大鼠随机分为4组：正常对照组、糖尿病模型组及白藜芦醇低剂量组及白藜芦醇高剂量组。糖尿病模型组、白藜芦醇低剂量组及白藜芦醇高剂量组一次性腹腔注射链脲菌素（STZ）（60 mg/kg）制备糖尿病大鼠模型。成模后低剂量组每日20 mg/kg，高剂量组每日100 mg/kg予白藜芦醇灌胃。裂隙灯显微镜照相机记录各组晶状体变化。12周实验结束时测定各组大鼠晶状体丙二醛（MDA）、超氧化物岐化酶（SOD）、谷胱甘肽过氧化酶含量。逆转录-聚合酶链反应（RT-PCR）检测各组大鼠晶状体SIRT1、肿瘤抑制因子P53、叉头转录因子1、核转录因子κB（NF-κB）表达情况。结果  糖尿病模型组大鼠晶状体均发生不同程度混浊，甚至完全混浊，形成白内障。白内障糖尿病大鼠晶状体MDA（7.96±0.51）nmol/mg·prot较正常对照组（4.21±0.27）nmol/mg·prot升高（P <0.01），糖尿病白内障大鼠晶状体SOD、谷胱甘肽过氧化酶[（31.92±5.03）和（7.43±1.53）u/mg·prot]较正常对照组[（61.86±6.17）和（13.61±2.27）u/mg·prot]降低（P <0.01）。高剂量白藜芦醇组大鼠晶状体MDA（4.64±0.42）nmol/mg·prot较白内障糖尿病大鼠晶状体（7.96±0.51）nmol/mg·prot降低（P <0.01）。高剂量白藜芦醇组大鼠晶状体SOD、谷胱甘肽过氧化酶[（52.41±6.54）和（12.76±1.72）u/mg·prot]较白内障糖尿病大鼠晶状体SOD、谷胱甘肽过氧化酶[（31.92±5.03）和（7.43±1.53）u/mg·prot]增高（P <0.01）。白内障糖尿病大鼠晶状体SIRT1 mRNA表达（0.187±0.034）较正常对照组大鼠（0.523±0.089）降低（P < 0.01）。高剂量白藜芦醇组大鼠晶状体SIRT1 mRNA表达（0.497±0.072）较白内障糖尿病大鼠晶状体（0.187±0.034）增强（P <0.01）。白内障糖尿病大鼠晶状体P53、叉头转录因子1、NF-κB mRNA表达（0.816±0.153）、（1.269±0.231）、（0.896±0.029）较正常对照组（0.592±0.104）、（0.674±0.112）、（0.495±0.008）增强（P <0.01）。高剂量白藜芦醇组糖尿病大鼠晶状体P53、叉头转录因子1、NF-κB mRNA表达（0.609±0.107）、（0.713±0.121）、（0.397±0.018）较白内障糖尿病大鼠（0.816±0.153）、（1.269±0.231）、（0.896±0.029）降低（P <0.01）。结论  白藜芦醇可能通过调节SIRT1表达，进一步调节下游基因P53、叉头转录因子1、NF-κB的表达，抑制和延缓晶状体上皮细胞凋亡，延缓糖尿病大鼠白内障的发生发展。

Abstract:

Objective To investigate the effects of resveratrol on silent information regulator protein 1 (SIRT1) gene expression in the lenses of diabetic cataract rat. Methods Eighty Wistar rats were randomly divided into four groups: control group (NC), diabetic model group (DC), low-dosage resveratrol group (RL) and high-dosage resveratrol group (RH). A single intraperitoneal injection with Streptozotocin (STZ 60 mg/kg) was used to establish the model of diabetic rats in diabetic model group, RL group and RH group. Resveratrol 20 mg/kg was administered to the rat model in the RL group daily, and resveratrol 100 mg/kg was administered to the rat model in the RH group daily through gastric perfusion. The changes of lenses were recorded by slit lamp microscope camera in the four groups. The content of malondialdehyde (MDA), superoxide dismutase (SOD) and gutathione peroxidase (GSH-Px) was detected in the lenses, and RT-PCR was used to assay SIRT1, P53, FOXO1 and NF-κB mRNA expressions in the lenses. Results The diabetic cataract rats were replicated successfully in diabetic model group. The expression of MDA was significantly increased (P < 0.01) and the expressions of SOD and GSH-Px were significantly decreased in the lenses of the diabetic cataract rats compared with the control group (P < 0.01). Compared to the model group, the expression of MDA was significantly decreased (P < 0.01), and the expressions of SOD and GSH-Px were significantly increased in the lenses of the RH group (P < 0.01). The expression of SIRT1 mRNA in the lenses of the model group was decreased significantly compared with the control group (P < 0.01). The expression of SIRT1 mRNA in the lenses of the RH group was increased significantly compared with that in the lenses of the model group (P < 0.01). The mRNA expressions of P53, FOXO1 and NF-κB in the lenses of the model group were increased significantly compared with those of the control group (all P < 0.01). The mRNA expressions of P53, FOXO1 and NF-κB in the lenses of the RH group were decreased significantly compared with those of the model group (all P < 0.01). Conclusions Resveratrol may regulate the expression of downstream genes P53, FOXO1 and NF-κB possibly by regulating the expression of SIRT1, ultimately inhibit and delay apoptosis of epithelial cells of the lenses and delay occurrence and development of diabetic cataract.