RESUMO
BACKGROUND:Theoretically, bone marrow-derived endothelial progenitor cells (EPCs) from liver fibrosis rats could be filtered by the pathological environment in vivo. These EPCs would be more adapted to the micro-environment of liver fibrosis, and easier to differentiate into mature endothelial cells participating in the intrahepatic vascular remodeling after transplanted into the liver.OBJECTIVE:To explore the effectiveness of transplantation of bone marrow-derived EPCs from the liver fibrosis environment in liver fibrosis rats.METHODS:Twenty-eight Wistar rats were randomly divided into three groups as follows:normal group (n=8) were injected with olive oil, twice per week; model group (n=10) were infused with carbon tetrachloride at a dose of 3 mL/kg body weight (double doses for the first time), twice per week, and infused with normal saline through the tail vein at 2, 3 and 5 weeks; EPCs transplantation group (n=10) were infused with carbon tetrachloride at a dose of 3 mL/kg body weight (double doses for the first time), twice per week, and infused with EPCs suspension through the tail vein at 2, 3 and 5 weeks. Six weeks after final injection, the angiogenesis, hepatocyte proliferation and pathological changes in the liver tissues were observed. The liver function and coagulation function were tested.RESULTS AND CONCLUSION:(1) The pathological changes of the liver:in the model group, fatty degeneration and hepatocyte necrosis in the liver tissue were serious, inflammatory cells were infiltrated around the portal and central vein,the portal areas expanded, and fibrous tissues overgrew. Compared with the model group, these changes were significantly relieved in the EPCs transplantation group (P < 0.05). (2) The expressions of liver-related proteins:compared with the normal group, the levels of hyaluronic acid, laminin, type III procollagen, vascular endothelial growth factor, epidermal growth factor were significantly increased in the model group (P < 0.05). Compared with the model group, the levels of hyaluronic acid, laminin and type III procollagen were decreased significantly (P < 0.05), and the levels of vascular endothelial growth factor and epidermal growth factor were increased in the EPCs transplantation group (P < 0.05). (3) Liver function and coagulation function:compared with the normal group, the liver function and blood blotting function of rats were seriously damaged in the model group (P < 0.05). Compared with the model group,the liver function and coagulation function were obviously improved in the EPCs transplantation group (P < 0.05). To conclude, transplantation of bone marrow-derived EPCs from the liver fibrosis environment is effective for liver fibrosis in rats. The mechanism may be associated with the promotion of angiogenesis in the liver.