Effect of bone morphogenetic protein-7 intervention on epidermal growth factor receptor expression in liver fibrosis / 中华传染病杂志

ABSTRACT

Objective To investigate the dynamic expressions of epidermal growth factor receptor (EGFR) in mice with liver fibrosis and the effect of bone morphogenetic protein-7 (BMP-7) intervention on the expression of EGFR,and to explore a new therapy target for fibrosis.Methods A total of 30 healthy male ICR mice were randomly divided into three groups6 mice in control group,18 mice in hepatic fibrosis group and 6 mice in BMP-7 intervention group.The model of mice with liver fibrosis was established by subcutaneous injection of carbon tetrachloride (CCl4) for 12 weeks.After administration of CCl4 for 8 weeks,human recombinant BMP-7 was given into mice in intervention group by intraperitoneal injection for 4 weeks.Hematoxylin-Eosin and Masson staining of liver tissues were employed to observe the pathological changes,and the semi-quantitative analysis of liver fibrosis was performed.Blood withdrawn from inferior vena cava was detected for levels of alanine aminotransferase (ALT),aspartate aminotransferase (AST) and albumin (Alb).The expressions of transforming growth factor-β1 (TGF-β1)mRNA and TGF-β1,EGFR,phosphorylation EGFR (pEGFR) protein in each group were detected using quantitative real time polymerase chain reaction and Western blot.Measurement date was compared using analysis of variance and Pearson correlation analysis.Results The model of mice with liver fibrosis was successfully established.In model group,the serum levels of ALT and AST increased,while the level of Alb decreased gradually.All these biochemical index improved after intervention of BMP-7 (ALT[153.9±18.1] U/L vs [191.3±24.5] U/L;AST[177.8±19.2] U/L vs [206.6±25.0] U/L;Alb[25.4±0.9] g/L vs [22.2±1.2] g/L; all P＜0.05).With the progress of fibrosis,TGF-β1,EGFR and pEGFR protein expressions increased gradually in model group and reached a peak at week 12,which was significantly different compared to the control group (all P＜0.05).In BMP-7 intervention group,the expressions of the three proteins decreased significantly compared to model group (TGF-β10.256 ± 0.006 vs 0.287±0.014,EGFR1.061±0.017 vs 1.094±0.014,pEGFR0.855±0.053 vs 1.007±0.063;all P＜0.05).Additionally,linear correlation analysis showed that expressions of both EGFR and pEGFR proteins were positively correlated with TGF-β1 protein (rs =0.895 and 0.859,respectively; both P＜0.05).Conclusions BMP-7 can suppress the pathogenesis of mouse liver fibrosis.The mechanism may rely on the regulation of EGFR and TGF-β1 expressions.