胰岛素样生长因子结合蛋白7在活化肝星状细胞促肝纤维化中的作用

目的 探讨胰岛素样生长因子结合蛋白7(IGFBP7)对肝星状细胞-T6合成分泌纤维连接蛋白的调节作用及抗IGFBP7抗体诱导肝星状细胞-T6凋亡的作用.方法 体外培养活化的肝星状细胞-T6分为5组:(1)空白对照组;(2)IGFBP7 20μg/L组;(3)抗IGFBF7抗体0.25 mg/L组;(4)抗IGFBP7抗体0.50 mg/L组;(5)抗IGFBP7抗体1.00 mg/L组.采用Western blot及ELISA法检测肝星状细胞-T6经IGFBP7作用24 h后纤维连接蛋白的表达及合成分泌量的变化;MTT比色法检测抗IGFBP7抗体对肝星状细胞-T6作用14 h后增殖抑制的影响,同时用流式细胞仪测定抗IGFBP7抗体对肝星状细胞-T6凋亡发生率的影响.采用单因素方差分析,两样本均数比较采用t检验,多重比较采用SNK-q检验.结果 肝星状细胞-T6经IGFBP7作用后纤维连接蛋白的表达及合成分泌量较空白对照组显著增加(t=22.06,7.43,P<0.05).抗IGFBP7抗体对肝星状细胞-T6的增殖具有明显抑制作用(F=14.70,P<0.05).抗IGFBP7抗体能够上调肝星状细胞-T6的凋亡率(F=63.79,P<0.05).结论 IGFBP7能够使细胞外基质的重要组成成分纤维连接蛋白的合成与分泌增加,抗IGFBP7抗体可以抑制肝星状细胞-T6的增殖并诱导其发生凋亡.

Role of insulin-like growth factor binding protein 7 in the process of hepatic fibrosis promoted by activated hepatic stellate cells

Objective To investigate the regulatory effect of insulin-like growth factor binding protein 7 (IGFBP7) on the synthesis and secretion of fibronection and the inhibiting effect of anti-IGFBP7 antibody on apop-tosis of hepatic stellate cell-T6 (HSC-T6). Methods HSC-T6 cultured in vitro were divided into blank control group, IGFBP7 20 μg/L group, anti-IGFBP7 antibody 0.25 mg/L group, anti-IGFBP7 antibody 0.50 mg/L group and anti-IGFBP7 antibody 1.00 mg/L group. HSC-T6 were treated by IGFBP7 for 24 hours, then the expression of fibronectin was detected by Western blot and the content of fibronectin by ELISA. After incubating HSC-T6 with anti-IGFBP7 antibody for 14 hours, the inhibiting effect of anti-IGFBP7 antibody on HST-T6 was evaluated by MTT assay, and the effect of anti-IGFBP7 on the apoptosis of HST-T6 was detected by flow cytometry. All data were analyzed by one-way ANOVA, t test and SNK-q test. Results The content and expression of fibronection in IGFBP7 20 mg/L group were significantly higher than those in the blank control group (t = 22.06, 7.43, P < 0.05). Anti-IGFBP7 antibody had an obvious inhibiting effect on the proliferation of HSC-T6 (F=14. 70, P < 0.05), and it also enhanced the ratio of apoptosis of HSC-T6 (F = 63.79, P < 0.05). Conclusions IGFBP7 can increase the synthesis and secretion of fibronectin which is the principal component of extracellular matrix. Anti-IGFBP7 antibody can inhibit the proliferation and promote the apoptosis of HSC-T6.