Histopathological changes in the liver of tree shrew (Tupaia belangeri chinensis) persistently infected with hepatitis B virus.

BACKGROUND: An animal model for HBV that more closely approximates the disease in humans is needed. The tree shrew (Tupaia belangeri) is closely related to primates and susceptible to HBV. We previously established that neonatal tree shrews can be persistently infected with HBV in vivo, and here present a six year follow-up histopathological study of these animals. METHODS: Group A consists of six tree shrews with persistent HBV infection, group B consists of three tree shrews with suspected persistent HBV infection, while group C consists of four tree shrews free of HBV infection. Serum and liver tissues samples were collected periodically from all animals. HBV antigen and HBV antibodies were detected by ELISA and/or TRFIA. HBV DNA in serum and in liver biopsies was measured by FQ-PCR. Liver biopsies were applied for general histopathologic observation and scoring, immunohistochemical detections of HBsAg and HBcAg, and ultrastructural observation with electron microscope technique. RESULTS: Hydropic, fatty and eosinophilic degeneration of hepatocytes, lymphocytic infiltration and hyperplasia of small bile ducts in the portal area were observed in group A. One animal infected with HBV for over six years showed multiple necrotic areas which had fused to form bridging necrosis and fibrosis, and megalocytosis. The hepatic histopathological scores of group A were higher than those of group B and C. The histopathological score correlated positively with the duration of infection. CONCLUSIONS: Hepatic histopathological changes observed in chronically HBV-infected tree shrews are similar to those observed in HBV-infected humans. The tree shrew may represent a novel animal model for HBV infection.

[Effects of Radix Ginseng and Radix Notoginseng formula on secretion of vascular endothelial growth factor and expression of vascular endothelial growth factor receptor-2 in human umbilical vein endothelial cells].

OBJECTIVE: To investigate the effects of Radix Ginseng and Radix Notoginseng formula on secretion of vascular endothelial growth factor (VEGF) and expression of vascular endothelial growth factor receptor-2 (VEGFR-2) in human umbilical vein endothelial cells (HUVECs) in vitro. METHODS: HUVECs were cultured in vitro. Bovine basic fibroblast growth factor (bFGF) at concentration of 320 U/mL and Radix Ginseng and Radix Notoginseng formula at concentrations of 0.1, 0.2 and 0.4 mg/mL were used to culture with HUVECs. And HUVECs in blank control group were cultured with culture solution only. After 24-hour culture, the content of VEGF in supernatant was detected by enzyme-linked immunosorbent assay and the expression of VEGFR-2 was detected by immunocytochemical staining and Western-blotting. RESULTS: Radix Ginseng and Radix Notoginseng formula at 0.4 mg/mL, the same as bFGF, increased VEGF content in the HUVEC supernatant and the number of VEGFR-2-positive HUVECs. Expression of VEGFR-2 protein in high-dose Radix Ginseng and Radix Notoginseng formula group was up-regulated as compared with the blank control group. CONCLUSION: Radix Ginseng and Radix Notoginseng formula can promote HUVEC proliferation and secretion of VEGF, as well as the expression of VEGFR-2 protein, which may be one of the mechanisms of Radix Ginseng and Radix Notoginseng formula in promoting angiogenesis.