青藤碱对白介素1β诱导的肾小管上皮细胞骨架变化和明胶酶活性的影响

目的 探讨青藤碱干预炎症介质诱导的肾小管上皮细胞表型转化的作用。 方法 用IL-1β(10 ng/ml)刺激小鼠肾小管上皮细胞株(MCT)和原代小鼠肾小管上皮细胞，并用青藤碱(10、100、500 μmol/L)进行干预。应用四唑盐(MTT)法测定青藤碱的细胞毒性。用免疫细胞化学法、Western印迹和RT-PCR分别测定细胞α-平滑肌肌动蛋白(α-SMA)、波形蛋白(Vim)蛋白和基因表达；明胶酶谱法测定明胶酶——基质金属蛋白酶类活性。 结果 IL-1β能够使肾小管上皮细胞α-SMA、Vim蛋白质合成和基因表达显著上调，明胶酶活性亦同时增强；各个浓度的青藤碱均可显著降低α-SMA、Vim蛋白质和基因的表达以及明胶酶活性。结论 青藤碱可抑制免疫炎症因子诱导的肾小管上皮细胞发生表型转化和降低明胶酶活性，可在一定程度上阻止肾小管上皮细胞迁移，防止肾小管萎缩，从而在防治肾小管间质纤维化中发挥其作用。

Effects of Sinomenine on the expression of cytoskeleton and MMP-2, MMP-9 in renal tubular epithelial cells

Objective To explore the effects of Sinomenine(Sin) on phenotype transdifferentiation in renal tubular epithelial cells. Methods Mice primary tubular epithelial cells and cell line (MCT) were cultured in vitro. Model group cells were stimulated by IL-1β(10 ng/ml). The cells of Sin group were co-incubated with Sin(10，100，500 μmol/L) simultaneously. The cells without IL-1β and Sin treatment were regarded as control group. The protein expression of α-smooth muscle actin(SMA) and Vimentin was assessed by immunohistochemistry and Western blotting. The mRNA expression of α-SMA and Vimentin was examined by RT-PCR. Secretion of matrix metalloproteinases was determined by zymography. Results The mRNA expression and protein level of α-SMA and Vimentin， and the enzyme activity of MMP-2 and MMP-9 in tubular epithelial cells stimulated with IL-1β were significantly higher than those in the controls. Sinomenine significantly reduced the expression levels of protein and mRNA of α-SMA and Vimentin. At the same time， the MMP-2 and MMP-9 activities were reduced markedly. Conclusion Sinomenine can decrease the transdifferentiation in renal tubular epithelial cells stimulated by inflammatory factor IL-1β and prevent renal interstitial fibrosis.