肾小管缺氧损伤中肾损伤分子-1表达信号通路的调节  

Regulation of KIM-1 expression by HIF-1 signal pathway in the hypoxic injury of renal tubular epithelial cell

作　　者：霍文谦[1] 靳风烁[1] 李黔生[1] 聂志林[1] 张克勤[1] 

机构地区：[1]第三军医大学大坪医院野战外科研究所泌尿外科,重庆400042

出　　处：《肾脏病与透析肾移植杂志》2011年第1期34-39,共6页Chinese Journal of Nephrology,Dialysis & Transplantation

基　　金：第三军医大学临床科研基金(2008XG182)

摘　　要：目的:观察肾损伤分子-1(KIM-1)及缺氧诱导因子1α(HIF-1α)在人近端小管上皮细胞(HK-2)缺氧复氧过程中的表达及相互关系,探讨HIF-1α对KIM-1表达的调控作用及机制。方法:收集缺氧、缺氧复氧后不同时段培养的HK-2细胞,用RT-PCR和Western-Blot检测KIM-1及HIF-1α表达,同时观察HIF激动剂(CoCl2)及抑制剂(雷帕霉素)对KIM-1表达的影响;应用凝胶迁移实验(EMSA)和染色质免疫沉淀实验(ChIP)验证KIM-1启动子区和HIF-1结合情况。结果:HK-2细胞缺氧复氧过程中KIM-1和HIF-1在mRNA水平和蛋白水平表达相关,HIF-1激动剂CoCl2或抑制剂雷帕霉素可上调或下调KIM-1表达,并呈剂量依赖性;EMSA表明HIF-1α可以和KIM-1启动子区HRE结合位点为模板所设计的双链寡核苷酸探针特异性结合,而且这种特异性结合受HIF-1α调节,同时ChIP实验证实了KIM-1启动子区和HIF-1α的结合。结论:KIM-1在近端肾小管上皮细胞缺氧损伤时的表达受HIF-1α调控,KIM-1可能作为HIF-1的下游分子参与肾损伤及修复过程。Objective ： To observe the relationship of kidney injury molecule-1 （ KIM-1 ） and hypoxia-inducible factor-1 ct （ HIF-1α） expression in the hypoxia/reoxygenation phases of HK-2 cell line, and to investigate the mechanism of the regulation of KIM-1 by HIF-lα. Methodology： The HK-2 cells were collected in different phases of hypoxia and reoxygenation to detect the expression of KIM-1 and HIF-lct by RT-PCR and Western-Blot, and the effects of agonist （Cocl2 ） /inhibitor （Rapamycin） of HIF-lα on the expression of KIM-1 were observed. Further more, the combination of the promoter region of KIM-1 and HIF-lα was validated by EMSA and CHIP. Results：The mRNA/protein expression of KIM-1 was correlated to that of HIF-lα in hypoxia/reoxygenation phases of HK-2 cell line. The agonist （ Cocl2 ） and inhibitor （Rapamycin） of HIF-lαcould respectively up-regulate and down-regulate the expression of KIM-1 expression, which was dose dependent. EMSA demonstrated that the designed Double-Stranded Oligonucleotide Probes based on the HRE combining site of the promoter region of KIM-1 could combined with HIF-1α, and this kind of combination was uhimately validated through CHIP. Conclusion： The expression of KIM-1 could be regulated by HIF-lα in hypoxic proximal tubular injury, which illustrated that KIM-1 was potentially a downstream molecule of HIF-1 involved in processes of injury and repair of the renal tubular epithelium.

关 键 词：肾小管上皮细胞 缺氧损伤 肾损伤分子-1 缺氧诱导因子-1 

分 类 号：R692[医药卫生—泌尿科学]