转化生长因子-β2在糖尿病大鼠视网膜中基因表达的研究(英文)  

Gene expression of transforming growth factor-β2 in retina of diabetic rats

作　　者：沈炜[1] 柳林[1] 

机构地区：[1]第二军医大学附属长海医院眼科,中国上海市200433

出　　处：《国际眼科杂志》2008年第6期1065-1069,共5页International Eye Science

基　　金：中国国家自然科学基金资助项目(No.30271391);中国上海市卫生局科研项目(No.034124);中国上海市卫生系统百名跨世纪优秀学科带头人培养计划(百人计划)基金资助项目(No.057)~~

摘　　要：目的:糖尿病视网膜病变(diabetic retinophthy,DR)是糖尿病在眼部的主要并发症,为我国四大致盲眼病之一。DR的病理基础是微血管病变,研究其发生、发展的机理对预防和治疗这一疾病具有重要的临床意义。而转化生长因子-β(transforming growth factor-β,TGF-β)是一类能够调节细胞生长和分化的多肽,具有多种生物学作用。本研究选择转化生长因子-β2(TGF-β2)为研究对象,检测其在不同时相点糖尿病大鼠视网膜中的基因表达情况,观察和分析TGF-β2的动态表达变化,探讨其在糖尿病视网膜病变发生、发展中的作用机制。方法:选10w龄正常雄性Sprague-Dawley(SD)大鼠,用链脲佐菌素(STZ)诱导SD大鼠建立糖尿病动物模型,血糖浓度大于16.7mmol/L定为糖尿病模型大鼠,于第4,8,12,16,20,24wk分别分离视网膜,液氮保存,应用RT-PCR检测糖尿病大鼠视网膜中不同时相点TGF-β2的基因表达。结果:(1)制备大鼠视网膜总RNA,甲醛变性凝胶电泳显示RNA样品完好无降解,能够用于基因表达分析。(2)用STZ成功诱导建立了大鼠糖尿病动物模型。(3)与正常对照组相比,糖尿病组大鼠视网膜中TGF-β2mRNA表达于4wk时升高,但统计学上差异无显著性(P>0.05);8wk时则下降,差异有显著性(P<0.05);12wk时仍下降,差异有显著性(P<0.05),较8wk时已出现上升趋势;16wk时与正常对照组无明显差异(P>0.05);20wk时则开始升高,但差异无显著性(P>0.05);24wk时继续升高,差异有显著性(P<0.05)。结论:TGF-β2的mRNA表达在糖尿病大鼠视网膜中较对照组于第8wk、12wk时明显降低,第24wk时明显升高,可以看出TGF-β2随时间变化呈双相性。一方面说明TGF-β作为一种重要的细胞生长调节因子的双向调控特点,另一方面也说明TGF-β2在DR中可能发挥着重要作用。AIM- To detect the gene expression of TGF-β2 in retinas of diabetic rats at different stages, to observe and analyze the effect of TGF-β2 on the retinas of diabetic rats, to explore the role of TGF-β2 in pathogenesis of diabetic retinopathy （DR）, and to provide experiment data and experience for further clinic studies. METHODS： Sprague-Dawley （SD） rats were used and retinas were dissected. The total RNA was isolated from which the first strand of cDNA was prepared. Diabetes mellitus was induced by a single intraperitoneal injection of 60mg/kg streptozotocin （STZ） and the rats were held without insulin treatment until sacrifice. Besides, agematched rats treated with saline were used as controls. Tail vein blood glucose was measured after 2 days and rats were considered hyperglycemic if blood glucose reading 〉 16.7mmol/L. Animals with blood glucose level 〈 16.7mmol/L were excluded from the study. The rats were killed at the 4th, 8th, 12th, 16th, 20th and 24th week respectively after hyperglycemic models were establish- ed. The retinas were separated and preserved in liquid nitrogen. The expressions of TGF--β2gene mRNA were detected by reverse transcription PCR （RT-PCR）. RESULTS. The RNA of rat retina was integrative enough to be used to further carry out PCR analysis. Compared with control groups, the expression of TGF-β2 mRNA in retinas of diabetic rats was up-regulated at the 4th week, but there was no statistical difference （ P 〉 0.05） ; it was down-regulated at the 8th week, and there was statistical difference （P 〈 0.05）; it was also down-regulated at the 12th week, and there was statistical difference （ P 〈 0.05） ; at the 16th week there was no statistical difference （P〉 0.05） ; it was up-regulated at the 20th week, but there was no statistical difference （P〉 0.05）; it continued to be upregulated at the 24th week, and there was statistical difference（ P〈 0.05）. ; CONCLUSION： Since the expression of TGF-β2 mRNA in retinas of diabetic rats

关 键 词：转化生长因子-Β2 基因表达 视网膜 糖尿病大鼠 逆转录聚合酶链反应 

分 类 号：R587.2[医药卫生—内分泌] R775.2[医药卫生—内科学]