人重度积水肾组织的基因芯片分析及左右不对称发育因子1的表达变化

目的 用基因芯片技术研究人重度积水肾与正常肾组织中表达差异的基因,探讨重度积水后人肾组织发生纤维化病变的分子机制.方法 收集临床重度肾积水新鲜标本12例(积水组)、正常肾组织标本6例(对照组),包括组织切片及核素肾动态显像(SPECT)检测结果.分别提取总RNA并纯化,选择转化生长因子(TGF)-β/骨形成蛋白(BMP)信号通路聚合酶链反应(PCR)芯片,采用比较阈值(AACt)法分析两组基因的表达差异.以免疫组织化学法检测两组标本中左右不对称发育因子(LEFTY)1的表达.结果 与对照组比较.积水组肾组织结构破坏严重,表现为广泛的纤维化样改变.SPECT提示积水组患肾肾小球滤过率(GFR)为(8.7±3.5)ml/min,而对照组GFR为(46.7±6.9)ml/min.PCR芯片筛查提示,积水组表达显著性上调的基因25个,包括BMP3、I型胶原α1链(COI α1)、Nodal、GSC、胰岛素样生长因子(IGF)1等;下调24个,包括LEFTY-1、BMV]、BMP2和骨形成蛋白内皮结合调节因子(BMPER)等.免疫组织化学检查发现,积水组肾组织中LEFTYA的表达明显低于对照组(P＜0.05),约为正常肾组织的(23.37～29.46)%.结论 LEFTY基因和蛋白在重度积水肾组织中的极低表达,提示LEFTY可能具有延缓纤维化形成并促进胶原降解的"双效应"作用,延缓肾积水-肾纤维化改变.

Analysis of gene-chip and expression of left-fight determination factor 1 in human extensive flbrotic renal tissues of patients with hydronephrosis

Objective To investigate the fibrosis-associated genes expressed in the tissue of extensive fibrotic kidney of patients with severe hydronephrosis.Methods Twelve extensive fibmtic kidneys in patients with severe hydronephrosis(hydrnephrosis group)were compared with 6 normal renal tissues (control group)by using real-time polymerase chain reaction(PCR)assay.All samples were collected from our hospital from Oct.2005 to Aug.2007.The results of real time PCR assay were processed with ΔΔCt method.When 2~(ΔΔc1) wag≤0.5 or≥2.the difference Was considered significant.Then the expression of left-right determination factor A(LEFTY-A)in both groups were detected by immunohistochemistry.Results A total of 49 differential genes expressed in the fibrotic renal tissues were screened out.of which,25 were up-regulated and 24 were down-regulated.The differential genes included members and their receptors of transforming growth factor(TGF)-β super family or bone morphogenetic protein(BMP) family,target molecular of TGF-β or BMP signal pathway and several relative regulators.And the gene of LEFTY-1.one of the most markedly-changed genes,in hydrnephrosis group Was 13.55-fold down-regulated as compared with control group.Immunohistochemistry analysis reveled that LEGTU-A protein in the sample of hydronephrosis group was significantly decreased as compared with that in control group(P＜0.05).Conclusion The LEFTY mRNA and protein expression Was decreased in human severely hydronephrotic renal tissue.indicating that LEFTY may play an important role in the inhibition of renal fibrosis resulting from long-term hydronephrosis.