干扰素-γ对肾小管上皮细胞转分化的作用  

Effects of Interferon-γ on Tubular Epithelial-myofibroblast Transdifferentiation in vitro

作　　者：李勤[1] 樊均明[1] 蒲蕾[2] 李孜[1] 秦伟[1] 苏白海[1] 

机构地区：[1]四川大学华西医院肾内科,成都610041 [2]四川省人民医院

出　　处：《四川大学学报（医学版）》2008年第6期895-899,943,共6页Journal of Sichuan University(Medical Sciences)

基　　金：国家自然科学基金(批准号30170437)资助

摘　　要：目的应用转化生长因子-β1(TGF-β1)诱导肾小管上皮细胞肌纤维母细胞转分化(TEMT),研究干扰素-γ(IFN-γ)对肾小管上皮细胞的表型重塑的作用和机制。方法将正常大鼠肾小管上皮细胞(NRK52E)分为空白组、诱导组(TGF-β13 ng/mL)、药物组(IFN-γ1000 IU/mL)及阻断组(TGF-β13 ng/mL+IFN-γ200、400、600、1000、2000、3000 U/mL),培养72 h后,观察α-平滑肌肌动蛋白(α-SMA)以及结缔组织生长因子(CTGF)的表达;测量α-SMA阳性细胞百分数和平均荧光强度(MCF),α-SMA mRNA,CTGF mRNA的表达;并测定上清液中胶原的含量。结果1诱导组细胞转分化为肌成纤维细胞样细胞,α-SMA阳性细胞百分数及MCF均明显增加(P<0.05);α-SMA mRNA和CTGF mRNA表达也明显增加(P<0.05);胶原含量升高(P<0.05)。2药物组的细胞形态、α-SMA mRNA、CTGF mRNA表达及胶原含量等与空白组的差异无统计学意义(P>0.05);3阻断组IFN-γ明显抑制了TGF-β1诱导的转分化,且呈剂量依赖;并抑制胶原合成(P<0.05)。结论IFN-γ能够负性调控TGF-β1诱导的TEMT,减少胶原分泌;IFN-γ对TEMT的负性调节作用可能是通过减少CTGF表达来实现的。Objective To investigate the effects of interferon-γ （IFN-γ） on tubular epithelial-myofibroblast transdifferentiation （TEMT） induced by transforming growth factor （TGF-β1）. Methods The normal rat kidney tubular epithelial cells （NRK52E） were cultured and divided into blank （NRK52E cells only） control group, TGF- β1 （3 ng/mL） treated group, IFN-γ （1000 IU/mL） treated group, and IFN-γ inhibition group （TGF-β1 3 ng/mL ＋ IFN-γ 200, 400, 600, 1000, 2000, 3000 IU/mL）. After 72 hours of treatment, the morphology of cells was observed under phase-contrast microscopy and scanning electron microscopy. The expressions of a-smooth muscle actin （α-SMA） and connective tissue growth factor （CTGF） were detected by immunocytochemistry. Flowcytometry was employed to measure the percentage of α-SMA^＋ ceils and the mean channel fluorescence （MCF）. The expressions of α-SMA mRNA and CTGF mRNA were examined by reverse transcription-polymerase chain reaction analyses （RT-PCR）. The level of collagen Ⅲ in the culture supernatant was measured by Enzymelinked immunoadsordent assay （ELISA）. Results NRK52E cells cultured in the control group showed a classic cobblestone morphology. TGF-β1 induced NRK52E cells to transdifferentiate into myofibrobtast-like cells, which showed strong α-SMA immunostaining. The TGF-β1 treated cells had higher percentage of α-SMA^＋ cells, MCF and α-SMA mRNA, increased CTGF mRNA expression, and ascended collagen Ⅲ than the blank controls （P〈 0.05）. IFN-γ treated alone did not make any changes to the cell morphology, the expressions of α-SMA mRNA and CTGF mRNA and the level of collagen Ⅲ （P2〉0.05）, IFN-γ exerted a strong inhibitory effect on the TEMT induced by TGF-β1. With the increase of IFN-γ, the percentage of α-SMA^＋ cells, the level of collagen Ⅲ , and the expressions of α-SMA mRNA and CTGF mRNA decreased （P〈0. 05）. Conclusion IFN-γ inhibits the TEMT induced by TGF-β1 and reduces the level of collagen

关 键 词：干扰索-γ 转分化 转化生长因子-Β1 结缔组织生长因子 肾小管上皮细胞 

分 类 号：R692[医药卫生—泌尿科学]