伴有高血压的糖尿病大鼠大血管病变SMC增殖早期基因表达谱的研究

目的:建立糖尿病大血管病变平滑肌细胞(SMC)增殖早期基因表达谱.方法:以自发性高血压大鼠(SHR)为对照,以STZ诱导SHR构建伴有高血压的糖尿病大鼠模型为实验组,分别在1周、2周、4周时抽提胸主动脉中膜的总RNA,获得两组cDNA的探针,与含有4 096条大鼠全长基因的cDNA表达谱芯片杂交,扫描芯片荧光信号图像,对差异表达基因数据进行生物信息学分析.结果:1周时有差异表达的基因321条,160条基因表达下降(ratio<0.5),161条基因表达上升(ratio>2).2周、4周时上述数据分别为414、238、176和403、202、201.分级聚类分析归为8类,3期全部高表达已知基因13条,其中4条持续升高的基因(CD74、Irf1、GAP43、CD36)都与细胞增殖有关.CYP2E1基因的表达大幅上调(ratio 1 w=34.54; ratio 2 w=24.82; ratio 4 w=33.57).结论:糖尿病大血管病变SMC增殖是多基因综合改变的结果,细胞增殖相关基因高表达是主要病理基础,CYP2E1基因可能是糖尿病大血管病变SMC增殖较重要或关键的基因.

Gene expression profile during early period of smooth muscle cell proliferation in macroangiopathy in diabetic rats with spontaneous hypertension

Objective:To establish the gene expression profile during early period of smooth muscle cell(SMC) proliferation in macroangiopathy in diabetic rats with spontaneous hypertension.Methods: Spontaneously hypertensive rats(SHR) were taken as control and a hypertensive diabetic rat model was established by streptozotocin(STZ) injection in SHR.The total RNAs were obtained from intima-media of thoracic aortas in 1-week,2-week and 4-week hypertensive diabetic rats separately.The mRNAs from SHR and hypertensive diabetic rats were reversely transcribed into the cDNAs.The 2 probes were then hybridized to the cDNA microarray containing 4 096 full length genes from rats.After high-stringent washing,the cDNA microarray was scanned and analyzed by computer image analysis.Bioinformatic analysis of altered gene expression was performed to find out the possible genes related to diabetic macroangiopathy.Results: A total of 321 genes were screened out in 1-week hypertensive diabetic rats,with 160 genes down-regulated(ratio<0.5-fold) and 161 up-regulated(ratio>2-fold);414 genes were screened out in 2-week hypertensive diabetic rats with 128 down-regulated and 176 up-regulated;and 403 genes were screened out in 4-week hypertensive diabetic rats with 202 down-regulated and 201 upregulated.The effective genes were divided into 8 groups by cluster analysis.Thirteen known genes were up-regulated in all 3 kinds of hypertensive diabetic rats,among which CD74,Irf1,GAP43 and CD36 had a steady increase and were related to cell proliferation.Furthermore,CYP2E1 gene was obviously up-regulated(ratio for the 1-week rats was 34.54,2-week was 24.82,and 3-week was 33.57).Conclusion: The gene expression profile based on cDNA micrioarray can be used for screening genes related with diabetic macroangiopathy.It is found that CYP2E1 might be an important gene responsible for proliferation of SMC in diabetic macroangiopathy.