摘要
目的:观察Janus激酶/信号转导和转录活化因子(JAK/STAT)信号的激活对高糖诱导肾小管上皮细胞转分化的影响。方法:体外培养人肾近曲小管上皮细胞株(HKCs),分别给予高糖和JAK拮抗剂AG490干预,采用免疫沉淀和Western印迹检测JAK2的磷酸化;Western印迹检测平滑肌肌动蛋白(α-SMA)、E-钙黏素(E-cadherin)及信号蛋白STAT1、STAT3、磷酸化STAT1(phospho-STAT1,p-STAT1)和p-STAT3的水平;酶联免疫吸附法(ELISA)测定细胞上清液中转化生长因子β1(TGF-β1)和I型胶原的分泌,逆转录聚合酶链反应(RT-PCR)检测TGF-β1mRNA表达。结果:与低糖对照组比较,高糖培养的HKCs中α-SMA的水平及p-JAK2、p-STAT1和p-STAT3比例明显上调;E-cadherin表达明显下调;TGF-β1mRNA表达增加;细胞培养上清液中TGF-β1、Ⅰ型胶原分泌增加。AG490明显抑制JAK2磷酸化、下调p-STAT1和p-STAT3的同时,明显抑制高糖刺激HKCs中α-SMA表达的升高,减轻E-cadherin表达下降程度;降低TGF-β1mRNA表达及TGF-β1、Ⅰ型胶原的分泌。结论:JAK/STAT信号途径参与高糖诱导的HKCs转分化,并刺激TGF-β1和细胞外基质的分泌。
AIM ： To investigate the effect of activation of JAK/STAT signaling pathway on the transdifferentiation induced by high concentration of glucose in renal proximal tubular epithelial cells （HKCs）. METHODS： Cultured HKCs cells were divided into four groups： low glucose group （LG）, high glucose group （HG）, high mannitol group （LG ＋ M）, and HG ＋ AG490 group （AG）. Immunoprecipitation and Western blotting analysis were used to determine the expression of tryosine phosphorylated Janus kinase 2 （ p - JAK2）. The protein expressions of STAT1, STAT3, p - STAT1 and p - STAT3 and expressions of α - SMA, E - cadherin were observed by Western blotting. The contents of TGF - β1 and type Ⅰ collagen in the supernatants of the cultured HKCs were detected by enzyme - linked immunoadsorbent assay （ELISA）. TGF- β1 mRNA were measured by reverse transcription and polymerase chain reaction （RT- PCR）. RESULTS： Compared with low glucose control group, the expression of JAK2, p - STAT1, p - STAT3 and TGF -β1 mRNA was significantly increased in HG group at different stimulated time from 6 h to 72 h. Meanwhile, the contents of TGF - β1 and collagen I in the supernatants and the expression of α- SMA were increased, the expression of E - cadherin were decreased. The expression of JAK2, p - STAT1, p - STAT3 and TGF - β1 mRNA and the levels of TGF - β1, collagen Ⅰ in the supernatants in HG ＋ AG490 group were obviously lower than those in HG group. The expressions of α - SMA and E - cadherin were also decreased in HG ＋ AG490 group. CONCLUSION ： Activation of JAK/STAT signaling pathway may be involved in the high glucose - induced transdifferentiation and overproduction of TGF - β1 and ECM proteins in HKCs.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2008年第2期325-329,共5页
Chinese Journal of Pathophysiology
基金
河北省自然科学基金资助项目(No.C2004000536)
