γ-干扰素促进Fas配体诱导血管平滑肌  

The significance of interferon-γ on Fas ligand-induced apoptosis of vascular smooth muscle cells

作　　者：郭兵[1] 杨斌[1] 吴雨哲 王坤[1] 李民[1] 孙平[1] 柯文波[1] 郑启昌[1] 宋自芳[1] 

机构地区：[1]华中科技大学同济医学院附属协和医院肝胆外科,武汉430022

出　　处：《中华实验外科杂志》2014年第4期706-708,共3页Chinese Journal of Experimental Surgery

基　　金：国家自然科学基金资助项目

摘　　要：目的探讨宋γ-干扰素（IFN-γ）对Fas配体（Fa出）诱导大鼠血管平滑肌细胞（VSMCs）凋亡的促进作用和机制。方法体外培养大鼠VSMCs，给予IFN-γ、FasL单独处理或两者联合处理后，采用Westernblot、流式细胞学分析、Hoeehst33342染色等技术，检测IFN-γ对VSMCs凋亡、Fas表达和分布的影响。观察衣霉素预处理是否影响IFN-γ联合F”L诱导的VSMCs凋亡，探讨Fas膜转位在IFN-γ促进FasL诱导VSMCs凋亡中的作用。结果、体外条件下，Hoechst33342染色显示，IFN-γ和FasL单独处理的凋亡诱导作用均较弱[凋亡率为（7．4±1．9）％、（6．8±2．5）％]，与前者比较，IFN-γ联合FasL可显著诱导VSMCs凋亡[凋亡率为（20．1±2．2）％，P〈0．01]。Westernblot结果显示，经IFN-γ处理36、72h后VSMCs总的Fas蛋白表达水平，相对表达量分别为0．469±0．129、0．383±0．045，与磷酸盐缓冲液（PBS）对照组（0．402±O．031）比较差异无统计学意义（P〉0．05），但可以诱导细胞表面Fas增多（0．266±0．042比0．042±0．017，P〈0．01）而细胞内Fas减少（0．193±0．038比0．426±0．074，P〈0．01）。膜转运阻断剂衣霉素预处理可有效抑制IFN-γ和FasL联合处理诱导的VSMCs凋亡，凋亡率[（6．14-0．8）％]较对照组[（23．0±1．0）％]显著降低（P〈0．01）。流式细胞学分析结果亦证实Hoechst染色结果。结论IFN-γ通过诱导Fas受体膜转位，显著增强VSMCs对FasL的敏感性，促进VSMCs凋亡。Objective To investigate the effect of interferon-γ （IFN-γ on Fas ligand （FasL） -in duced apoptosis of rat vascular smooth muscle cells （VSMCs） and explore the underlying mechanism. Methods VSMCs isolated from rat aorta were cultured in vitro and treated with IFN-γor FasL alone, or both in combination, with or without the pretreatment of Tunicamycin. Hoechst 33342 staining and flow cyto metric analysis of Annexin V-fluoresceine isothiocyanate （FITC）/propidium iodide （ PI ） staining were em ployed to define the effect of IFN-γon FasL-induced VSMCs apoplosis. Protein levels of surface Fas, cyto plasmic Fas and total Fas were detected by Western blotting in order to observe the expression and distribu tion of Fas. Results As shown by both Hoeehst 33342 staining, apoptosis of VSMCs was only slightly in duced by treatment with IFN-γ or FasL alone [ apoptotie index of （7.4 ± 1.9 ） % vs. （6. 8 ± 2. 5 ） % ], but significantly induced by IFN-γ and FasL in combination [ （20. 1 ± 2. 2）%, both P 〈 O. 01 ]. Increased sur face Fas （ relative level of O. 266 ± 0. 042 vs. O. 042 ± O. 017, P 〈 O. O1 ） , decreased cytoplasmic Fas （ O. 193 ±0. 038 vs. O. 426 ±0. 074, P 〈0. O1 ） but unchanged total Fas expression （0. 469 ＋0. 129/0. 383 ±0. 045 for 36 h/72 h vs. 0. 402 ± 0. 031 for 0 h, both P 〉 O. 05 ） were detected by Western blotting after IFN-γ treatment. And pretreatment with membrane trafficking inhibitor Tunicamycin significantly diminished FasL-indueed VSMCs apoptosis promoted by IFN-γ. The apoptotic index [ （6. 1 ± 0. 8）% ] were less than that of control [ （23.0 ± 1.0）% , P 〈0. 011- Flow eytometric analysis also confirmed the results of Ho echst 33342 staining. Conclusion Instead of inducing VSMCs apoptosis directly, IFN-γchanges the Fas distribution by promoting translocation of Fas receptor to the cell membrane, which significantly enhances the sensitivity of VSMCs to FasL-indueed apoptosis.

关 键 词：Γ-干扰素 血管平滑肌细胞 FAS配体 FAS 细胞凋亡 

分 类 号：R329[医药卫生—人体解剖和组织胚胎学]