p38MAPK介导高糖下调肾小管上皮细胞表达BMP-7  

High glucose induces down-regulation of BMP-7 expression in renal tubular epithelial cells through p38MAPK pathway

作　　者：肖瑛[1] 方开云[1] 石明隽[1] 刘瑞霞[1] 桂华珍[1] 郭兵[1] 张国忠[1] 

机构地区：[1]贵阳医学院病理生理学教研室,贵州贵阳550004

出　　处：《中国病理生理杂志》2010年第9期1759-1763,共5页Chinese Journal of Pathophysiology

基　　金：国家教育部博士点专项科研基金资助项目(No20060660001);贵州省攻关项目(No黔科合SY字[2008]3042);贵阳医学院院青年基金资助项目(NoK2007-9);贵州省科学技术基金资助项目(No黔科合J字[2008]2167号)

摘　　要：目的:观察高糖环境中培养的原代肾小管上皮细胞骨形态发生蛋白-7(BMP-7)表达及p38丝裂原活化蛋白激酶(p38MAPK)信号通路的作用。方法:原代培养大鼠肾小管上皮细胞,随机分为正常对照组、高糖组、p38MAPK阻断剂SB202190+高糖组和高渗组,处理72h后收集贴壁细胞,免疫细胞化学检测BMP-7和纤维连接蛋白(FN)表达;Westernblotting检测p38MAPK和磷酸化p38MAPK(p-p38MAPK)的表达;RT-PCR法检测BMP-7和FNmRNA水平。结果:正常对照组肾小管上皮细胞BMP-7主要表达于细胞浆,有少量总p38MAPK与FN表达,未见p-p38MAPK;高糖状态激活了p38MAPK,p-p38MAPK蛋白表达明显增加,FN的表达也明显增多而BMP-7的表达显著减少;与SB202190共同培养72h后,p-p38MAPK的表达较高糖组减少约80%,BMP-7的表达却被显著上调,而FN的表达减少。高渗组与正常对照组比较无明显差异。结论:高糖状态下肾小管上皮细胞BMP-7蛋白和mRNA均减少,阻断p38MAPK信号通路可促进内源性BMP-7增多,提示p38MAPK可能参与高糖下调肾小管上皮细胞BMP-7的表达。AIM： To observe the BMP-7 expression in primary renal tubular epithelial cells cultured with high glucose and to investigate the role of p38MAPK signaling pathway. METHODS： The primary renal tubular epithelial cells were randomly treated with normal glucose,high glucose,co-incubation of high glucose with specific p38MAPK in-hibitor SB202190 or D-mannitol for 72 h. The protein expression of BMP-7 and fibronectin （ FN） in all the cells was as-sessed by the method of immunocytochemistry. The protein expression of p38MAPK and p-p38MAPK was determined by Western blotting. The mRNA expression of BMP-7 and FN was detected by RT-PCR. RESULTS： In normal glucose group,BMP-7 was highly expressed in the cytoplasm of tubular epithelial cells,and only small amounts of p38MAPK and FN,but not p-p38MAPK,were observed. High glucose was able to activate p38MAPK,and therefore the protein of p-p38MAPK increased remarkably in high glucose-treated cells. High glucose also enhanced FN production. Mean-while,the expression of BMP-7 decreased. Co-incubation of high glucose with SB202190 for 72 h reduced the activity of p38MAPK by 80% and the FN expression was also decreased,while the BMP-7 expression significantly increased. No significant difference of the BMP-7 or FN expression between control group and D-mannitol group was observed. CON-CLUSION： The expression of BMP-7 at mRNA and protein levels in renal tubular epithelial cells is decreased under the condition of high-glucose cultivation. Suppression of p38MAPK signaling pathway stimulates endogenous BMP-7 expres-sion,indicating that p38MAPK pathway may be involved in the down-regulation of BMP-7 in renal tubular epithelial cells by high glucose.

关 键 词：骨形态发生蛋白质-7 P38MAPK 糖尿病肾病 大鼠 

分 类 号：R363[医药卫生—病理学]