高糖对肾小管上皮细胞表达CTGF的影响及P38MAPK通路在其中的作用  

Effect of high glucose exposure on connective tissue growth factor expression in cultured human renal tubular epithelial cells and the role of p38MAPK pathway

作　　者：汤珣[1] 章俊[1] 蔡德鸿[2] 曾莉[3] 

机构地区：[1]南方医科大学珠江医院肾内科,广东广州510280 [2]南方医科大学珠江医院内分泌科,广东广州510280 [3]南方医科大学公共卫生与热带医学学院,广东广州510515

出　　处：《南方医科大学学报》2009年第1期50-53,共4页Journal of Southern Medical University

基　　金：广东省自然科学基金(200332842);广东省科技计划项目(2007B031503001)

摘　　要：目的探讨高糖对人肾小管上皮细胞结缔组织生长因子(CTGF)mRNA及蛋白表达的影响,以及p38丝裂原激活蛋白激酶(p38MAPK)信号途径在其中的作用。方法以高糖刺激体外培养的人肾小管上皮细胞株HKC,应用RT-PCR,免疫组化、间接免疫荧光、Western blotting等分析技术,检测高糖刺激24、48、72、96h,以及20d时HKC表达CTGFmRNA及蛋白的影响,并观察以SB203580特异性阻断p38MAPK信号传导途径后上述过程的变化。结果体外培养HKC的CTGFmRNA与蛋白含量极低,高糖刺激48h后HKC表达CTGFmRNA水平达峰值,以后逐渐下降,96h时接近正常水平,但长期(20d)高糖刺激的HKC,其表达CTGFmRNA水平稳定高于正常对照组2倍。而随高糖刺激时间的延长,HKC细胞表达CTGF蛋白水平进行性升高,长期(20d)持续高糖刺激可使CTGF蛋白表达水平达到正常组的5倍左右。SB203580能显著抑制高糖引起的CTGFmRNA及蛋白的高表达。结论持续高糖刺激可以引起体外培养的人肾小管上皮细胞表达CTGF显著升高,提示CTGF高表达是糖尿病肾病肾小管间质纤维化发生的重要环节,而p38MAPK信号途径可能参与了这一过程。Objective To observe the effect of high glucose exposure on connective tissue growth factor （CTGF） expression in cultured human renal tubular epithelial cells and investigate the role ofp38MAPK pathway in this process. Methods Human renal tubular epithelial cells （HKC） with and without SB203580 pretreatment were cultured in the presence of high glucose levels for 24, 48, 72, 96 h and 20 days. RT-PCR, immunohistochemical staining, indirect fluorescence staining and Western blotting were used to detect the changes in CTGF mRNA and protein expressions in the cells after the treatment. Results Low levels of CTGF mRNA and protein were detected in cultured HKC cells, and after high glucose treatment, the mRNA expression increased gradually and reached the peak level at 48 h, then followed by gradual decrease till recovering the baseline level at 96 h. Prolonged high glucose treatment for 20 days resulted in persisted high CTGH mRNA expression twice the level in the control group. The expression level of CTGF protein also increased progressively as the treatment time then prolonged, and long-term （20 days） treatment increased the expression by 4 folds in comparison with the expression in the control cells. SB203580 significantly inhibited the increase in the expressions of CTGF mRNA and protein stimulated by high glucose treatment. Conclusion High glucose treatment can increase CTGF mRNA and protein expressions in cultured human renal tubular epithelial cells, suggesting that increased CTGF levels is a key event in the pathogenesis of renal tubulo-interstitial fibrosis in patients with diabetic nephropathy, p38MAPK pathway may also participate in this process.

关 键 词：结缔组织生长因子 人肾小管上皮细胞 高糖 P38丝裂原激活蛋白激酶 

分 类 号：R692[医药卫生—泌尿科学]