Effect and mechanism of rat hepatocytes on proliferation and activation of hepatic stellate cells

Objective To observe the effect of hepatocytes on the biologic activity of primary hepatic stellate cells(HSC),and to investigate its mechanism.Methods HSC isolated from SD rats were cocultured with rat hepatocyte line BRL for 48 h, then the phenotypic alternation of HSC was observed under phase contrast microscope.The expressions of α-smooth muscle actin(α-SMA) and precollagen typeⅠ were detected by Western blot.The apoptosis of HSC was detected by TUNEL method.The primary HSC was cultured in the supernatant of BRL cells or control culture medium for 48 h,and the proliferation of HSC was detected by MTT method.The differences of cytokines' expression between the supernatant of BRL cells and control culture medium were analyzed by using cytokines antibody arrays.ResultsBRL cells significantly facilitated proliferation,apoptosis,contractibility,α-SMA and procollagen type Ⅰ expression of primary HSC(P0.01).Antibody arrays indicated that there was a higher up-regulation of vascular endothelial growth factor(VEGF),monocyte chemoattractant protein-1(MCP-1),and tissue inhibitor of metalloproteinase-1(TIMP-1) in the supernatant of BRL cells than that in control culture medium.Conclusion Hepatocytes stimulate proliferation and activation of HSC,which may due to its secretion of VEGF,MCP-1 and TIMP-1.