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Hepatic Growth Factor (hepatic + growth_factor)
Selected AbstractsIsolation and functional identification of a novel human hepatic growth factor: Hepatopoietin Cn,HEPATOLOGY, Issue 3 2008Chun-Ping Cui Hepatic stimulating substance (HSS) was first isolated from weanling rat liver in 1975 and found to stimulate hepatic DNA synthesis both in vitro and in vivo. Since then, mammalian and human HSS have been investigated for their potential to treat hepatic diseases. However, the essential nature in composition and structure of HSS remain puzzling because HSS has not been completely purified. Heating, ethanol precipitation, and ion-exchange chromatographies had been carried out to isolate the protein with specific stimulating activity from newborn calf liver, and [3H]thymidine deoxyribose (TdR)/bromodeoxyuridine (BrdU) incorporation and carboxyfluorescein diacetate succinimidyl ester (CFSE)-based proliferation assay to determine the bioactivity in vitro and in vivo. We report the purification of a novel 30-kDa protein from a crude extract of calf liver HSS. This protein is a member of the leucine-rich acidic nuclear protein family (LANP) and has been named hepatopoietin Cn (HPPCn). Studies of partially hepatectomized (PH) mice show that levels of HPPCn messenger RNA (mRNA) increase after liver injury. Furthermore, the recombinant human protein (rhHPPCn) was shown to stimulate hepatic DNA synthesis and activate signaling pathways involved in hepatocyte proliferation in vitro and in vivo. Conclusion: HPPCn is a novel hepatic growth factor that plays a role in liver regeneration. (HEPATOLOGY 2008;47:986,995.) [source] HIP/PAP accelerates liver regeneration and protects against acetaminophen injury in mice,HEPATOLOGY, Issue 3 2005Hanh-Tu Lieu Human hepatocarcinoma-intestine-pancreas/pancreatic-associated protein HIP/PAP is a secreted C-type lectin belonging to group VII, according to Drickamer's classification. HIP/PAP is overexpressed in liver carcinoma; however, its functional role remains unclear. In this study, we demonstrate that HIP/PAP is a paracrine hepatic growth factor promoting both proliferation and viability of liver cells in vivo. First, a low number of implanted hepatocytes deriving from HIP/PAP-transgenic mice (<1:1,000) was sufficient to stimulate overall recipient severe combined immunodeficiency liver regeneration after partial hepatectomy. After a single injection of HIP/PAP protein, the percentages of bromodeoxyuridine-positive nuclei and mitosis were statistically higher than after saline injection, indicating that HIP/PAP acts as a paracrine mitogenic growth factor for the liver. Comparison of the early events posthepatectomy in control and transgenic mice indicated that HIP/PAP accelerates the accumulation/degradation of nuclear phospho,signal transducer activator transcription factor 3 and tumor necrosis factor , level, thus reflecting that HIP/PAP accelerates liver regeneration. Second, we showed that 80% of the HIP/PAP-transgenic mice versus 25% of the control mice were protected against lethal acetaminophen-induced fulminate hepatitis. A single injection of recombinant HIP/PAP induced a similar cytoprotective effect, demonstrating the antiapoptotic effect of HIP/PAP. Comparison of Cu/Zn superoxide dismutase activity and glutathione reductase-like effects in control and transgenic liver mice indicated that HIP/PAP exerts an antioxidant activity and prevents reactive oxygen species-induced mitochondrial damage by acetaminophen overdose. In conclusion, the present data offer new insights into the biological functions of C-type lectins. In addition, HIP/PAP is a promising candidate for the prevention and treatment of liver failure. (HEPATOLOGY 2005;42:618,626.) [source] Lack of evidence that bone marrow cells contribute to cholangiocyte repopulation during experimental cholestatic ductal hyperplasiaLIVER INTERNATIONAL, Issue 4 2006Yuki Moritoki Abstract: Background: Ductopenia is observed in end-stage human cholestatic diseases. The limited capability of cholangiocytes for proliferation is suggested to be the principal reason. Recently, bone marrow cells (BMCs) have been reported to behave as hepatic stem cells; however, their capability to differentiate into cholangiocytes in cholestasis remains unclear. Methods: Normal mice were lethally irradiated to suppress the proliferation of self-BMCs; thereafter, the BMCs from enhanced green fluorescent protein (EGFP)-transgenic mice were transferred to recipients. Chronic cholestasis was induced by 0.1%,-naphtylisothiocyanate (ANIT) feeding. The proliferation of cholangiocytes and oval cells was assessed morphologically and immunohistchemically (cytokeratin-7 (CK-7), A6). Proliferative activity (proliferating cell nuclear antigen (PCNA) protein expression), hepatic growth factor (HGF) receptor (c-Met), stem cell factor receptor (c-kit), Notch2 and Hes1 expression were also evaluated. Results: Marked cholangiocyte proliferation was observed in ANIT-fed mice. However, no EGFP/CK-7 double positive cells were identified in any of the liver specimens after BMCs transfer (Tx). In hepatic parenchyma, there were scattered EGFP-positive cells, although none of them were positive for CK-7. Conclusions: In spite of the significant ductular proliferations after ANIT feeding, no EGFP-positive cholangiocytes were confirmed by any other means in this chronic cholestasis model. Thus, different from hepatocytes, BMCs Tx seems not to contribute to the differentiation of cholangiocytes. Future studies are feasible to clarify the origin of proliferative cholangiocytes observed in this chronic cholestatic ductular hyperplasia model. [source] |