大黄对糖尿病肾病大鼠肾皮质基因表达谱的影响

目的：研究大黄对糖尿病肾病大鼠肾皮质基因表达谱的影响及分析大黄对糖尿病肾病在基因水平上的作用机制。方法：20只雄性SD大鼠随机分为4组：正常对照组、用STZ诱导的糖尿病肾病组、糖尿病肾病大鼠给予大黄提取物治疗的大黄治疗组和糖尿病肾病大鼠给予安慰剂的阴性对照组。从4组SD大鼠的肾皮质中抽提mRNA,分别用Cy3、Cy5荧光标记，经反转录分别合成正常对照组与糖尿病组、大黄治疗组和对照组动物来源的cDNA探针；同时将Cy2,Cy5荧光标记的cDNA探针等量地与BioDoor基因表达谱芯片杂交，结果与扫描仪扫描并用软件进行分析统计。结果：正常对照组与糖尿病肾病组之间差异表达的基因有335条，占芯片基因总数的8．4％，其中12条基因在糖尿病肾病时表达量明显下降，而323条基因在糖尿病肾病时表达量明显上升。大黄治疗组和阴性对照组之间差异表达的基因有128条，占芯片基因总数的3．3％，其中有8条基因在大黄治疗以后明显上升，而120条基因在大黄治疗以后明显下降。并且，在糖尿病肾病中部分基因的表达变化在大黄治疗后可被逆转。结论：大黄能上调或下调部分差异表达的基因，并在一定程度上能逆转STZ诱导的基因表达谱。

Effect of rhubarb extract on gene expression profile in diabetic nephropathy rats

Objective To study the effect of rhubarb extract on the gene expression profile in diabetic nephropathy rats, and analyze the mechanism of rhubarb on diabetic nephropathy in gene expression level. Methods Male rats without any treatments were used as the normal control group. Diabetic nephropathy was induced by streptozotocin in the rats as the diabetic nephropathy group. The diabetic nephropathy rats were treated with rhubarb extract as the rhubarb-treated group and with placebo as negative control group. The renal cortex was obtained from four groups. Cy5 or Cy3 fluorescent labeled DNA probes were prepared from mRNA and hybridized against the BioDoor Genechip, finally fluorescent signals were assayed and raw data was analyzed. Results There were about 8. 4 % genes altered in gene expression profile. The expression level of 12 genes were downregulated while 323 genes were upregulated significantly in the renal cortex of the diabetic animals. Compared with the negative control rats, 120 genes were downregulated and eight genes were upregulated significantly in the rhubarb-treated group, which occupied 3.3% of the total genes on the genechip. Furthermore, the expression changes of partial altered genes in the diabetic nephropathy group were reversed by rhubarb treatment. Conclusion Rhubarb is effective on the downregulation or upregulation of some differential expression genes, and can partially reverse streptozotocin-induced gene expression profile.