Silymarin and hepatoprotection / 中南大学学报(医学版)

OBJECTIVE@#To determine the hepatoprotective effect of silymarin with Chang cell cultures. Specifically, to investigate the antioxidant properties of silymarin and its protective function in reducing pro-apoptotic markers.@*METHODS@#Intracellular free radical levels were assessed with dichlorofluorescein (DCF) fluorescence after exposing cells to an oxidative stress of 400 μmol/L H2O2 for 20 min. Levels of cellular ATP and bax expression were examined to evaluate the protective effects of silymarin.@*RESULTS@#Silymarin significantly reduced the DCF fluorescence signal. Cell viability, assessed by the MTT assay, showed that silymarin enhanced the cell growth. Drug treatment was also associated with enhanced ATP levels, and reduced Bax and protein mRNA levels.@*CONCLUSION@#Silymarin can function as a hepatoprotectant against free radical damage due to oxidative stress. The protective nature extends to reducing levels of pro-apoptotic Bax protein. Silymarin may be a useful adjuvant for the treatment of specific liver diseases.

Prospect of bone morphogenetic protein 13 in liver diseases / 中南大学学报(医学版)

Bone morphogenetic proteins (BMPs) belong to TGF-β superfamily and are a group of important cytokines involved in cell differentiation, proliferation and embryonic development. Multiple BMPs play important roles in several functions of vertebrates. Signaling pathway of BMPs is known to be mediated by Smad proteins, which include 8 members while Smad1, Smad5 and Smad8 are involved in BMPs signal transduction while Smad2 and Smad3 are mediated TGF-β signal transduction. Although several BMPs such as BMP4 and BMP9 have been documented in the liver, BMP13 has not been examined in the liver. BMP13 also known as growth differentiation factor (GDF)-6 or cartilage-derived morphogenetic protein (CDMP)-2 is one of the BMPs family members. Function of BMP13 has been investigated in bone and tendon repair. It can stimulate tendon-like cell proliferation. However, our recent findings revealed that there was expression of BMP13 in the liver and its expression was modulated during metabolic disorders. The current article is to understand biological function of BMP13 especially in the liver.

Identifying the targets for treatment of liver fibrosis and hepatocellular carcinoma from both Western medicine and Chinese medicine / 中国结合医学杂志

Liver fibrosis and hepatocellular carcinoma (HCC) are emerging health problems worldwide. Number of death due to HCC was steadily increased during the last decade. Although liver fibrosis and HCC have been investigated extensively, there are no successful and/or satisfactory therapies especially for patients with HCC. From our understanding of both Western medicine and Chinese medicine, it could identify the targets in liver fibrosis and HCC for intervention with Chinese medicine such as bone morphogenetic protein 4 (BMP-4). BMP-4 expression was significantly increased in both liver fibrosis and HCC and saponin class of certain Chinese herbs could regulate its expression. Therefore, BMP-4 could be one of the targets for treatment of liver fibrosis and HCC from integrative medicine.

Treatment of acute liver injury by intrasplenic transplantation of hepatic stem cells combined with heparin in rats / 中南大学学报(医学版)

OBJECTIVE@#To determine the treatment effects of transplanted hepatic progenitor cells (WB-F344 cells) combined with heparin on the acute liver injury in SD rats.@*METHODS@#A total of 2*10(7) hepatic stem cells (WB-F344) infected with GFP lentivirus and 8 μL heparin were transplanted through the spleen in SD rats with acute liver injury, which was induced by an intraperitoneal injection of CCl4. The liver and spleen tissues underwent fluorescence examination 1 day after the transplantation. The liver functions were tested, and the liver tissues were histopathologically examined on the 3rd, 7th, 14th, and 28th day of the cell transplantation.@*RESULTS@#The transfected WB-F344 cells expressed GFP 3 days after the lentivirus infection and were found in the rat liver 1 day after the WB-F344 transplantation. The liver function and histopathological recovery of the liver tissues in the group of WB-F344 transplantation were better than those of the control group (P<0.05).@*CONCLUSION@#Transplantation of hepatic stem cells combined with heparin can promote the liver recovery in rats with acute liver injury induced by CCl4.

Effect of bone morphogenetic protein-4 on the proliferation and differentiation of rat hepatic precursor cells / 中南大学学报(医学版)

OBJECTIVE@#To determine the regulation effect of bone morphogenetic protein-4 (BMP-4) on the proliferation and differentiation of rat hepatic precursor cells.@*METHODS@#We used Noggin (200 ng/mL) as the function blocking control of BMP-4, and the hepatic precursor cells of WB-F344 were treated with recombinant BMP-4 at 50 ng/mL at different time points. The proliferation of WB-F344 cells were tested by methyl thiazolyl tetrazolium (MTT) colorimetric assay. The ultrastructural characters of differentiated WB-F344 cells regulated by BMP-4 were observed under a transmission electron microscope. RT-PCR was used to examine mRNA expression of specific molecular markers for different cellular phenotypes potentially differentiated from the WB-F344 cells.@*RESULTS@#At different time points, the absorbance values in the BMP-4 treatment groups were higher than those in the control groups of Noggin and blank treatment (P<0.01). The WB-F344 cells treated with BMP-4 exhibited typical ultrastructural characters of well-differentiated epithelial cells. The hepatocyte mRNA markers were more significantly promoted in the differentiated WB-F344 cells in the BMP-4 treatment group than those in the other 2 control groups.@*CONCLUSION@#BMP-4 can promote the proliferation and directional differentiation towards hepatocytes of rat hepatic precursor cells of WB-F344.

Construction and further identification of eukaryotlc expression plasmid containing rat hepatocyte growth factor gone and augmenter of liver regeneration gene / 中华传染病杂志

Objective To construct and identify an eukaryotic expression plasmid containing rat hepatocyte growth factor(rHGF)gene and rat augmenter of liver regeneration(rALR)gene,so that to provide experimental basis for developing new treatments of hepatic fibrosis.Methods The gene fragments of rHGF and rALR were amplified from recombinant prokaryotic plasmid pUC18-rHGF and pUC18-rALR by polymerase chain reaction(PCR),respectively,then were spliced by overlap extension PCR with a linker,and the fusion gene rHGF-linker-rALR was constructed.The fusion gene was directionally inserted into the eukaryotic expression plasmid pcDNA3.1 between restriction sites of Kpn Ⅰ and Xba Ⅰ to construct the recombinant eukaryotic expression plasmid pcDNA3.1-rHGF-linker-rALR,and the new constructed recombinant plasmid was identified by double restriction digestion and DNA sequencing.Results DNA fragments of 2200 bp and 400 bp were observed after the electrophoresis of products amplified from recombinant prokaryotic plasmid pUC18-rHGF and pUC18-rALR,respectively,which was consistent with the theoretical value.The electrophoresis of fusion gene rHGF-linker-rALR obtained by overlap extension PCR technique showed only a 2 600 bp DNA fragment,which was in accordance with the expected value.Electrophoresis of products of pcDNA3.1-rHGF-linker-rALR digested with Kpn Ⅰ and Xba Ⅰ showed two DNA fragments with 2600 bp and 5400 bp,which were both consistent with the expected value.The sequences were confirmed correctly by DNA sequencing.Conclusion The recombinant eukaryotic expression plasmid pcDNA3.1-rHGF-linker-rALR is successfully constructed,which provides experimental basis for developing gene therapy of hepatic fibrosis.

Apoptotic and survival signals in hepatic stellate cells / 中南大学学报(医学版)

Hepatic stellate cells (HSCs) play an important role in hepatic fibrogenesis.In response to liver injury, HSCs undergo a process called activation, which involves 2 stepsinitiation from quiescent phenotype to myofibroblast-like phenotype, and perpetuation that maintains the activated phenotype of HSCs. The fate of the activated HSCs depends on the apoptotic and survival signals that they receive. The apoptosis of HSCs results from a series of complex and interrelated signaling events. Apoptotic signals for the activated HSCs include proteins from membrane receptors, such as death receptors, nerve growth factor receptor and peripheral-type benzodiazepine receptor, as well as proteins from cytoplasm such as Bcl-2 family members. The survival signals for the activated HSCs are induced by some kinases and cytokines including tissue inhibitors of metalloproteinase-1, Rho/Rho kinase, platelet-derived growth factor, transforming growth factor beta-l, and insulin-like growth factor-1. Approaches that specifically initiate HSC apoptosis are promising to be direct and effective strategies to treat liver fibrosis. Although it remains unclear whether the activated HSCs could be reversed back to the quiescent phenotype,the different expression and sensitivity of pro-apoptotic and survival molecules between quiescent and activated HSCs provide a prospect to develop therapeutic approaches that specifically targets apoptosis of the activated HSCs. These therapeutic strategies to induce HSC apoptosis are current research hotspot and the future for the patients with liver fibrosis and cirrhosis.