OBJECTIVETo investigate in vitro methods of inducing mouse embryonic stem cell(s) (ESC) into hepatocytes.

METHODSE14 mouse ESC were cultivated in suspension and plated to form aggregates, the embryoid bodies. They were allowed to outgrow on the plated culture with the stepwise addition of growth factors-- acidic fibroblast growth factor (aFGF), hepatocyte growth factor (HGF) and oncostatin M (OSM) into the culture medium. Morphology was investigated by phase contrast microscopy. Gene expressions of endodermal and liver specific mRNA were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Indocyanine green (ICG) uptake assay and periodic acid-Schiff reaction (PAS) were performed to assess the differentiation and function of the cells.

RESULTSMorphology analysis revealed a difference between ESC-derived hepatic cells and original ESC in that the former showed distinct round or polygonal shapes with clear boundaries, some arranged tightly in cords, while the latter grew in clones without clear boundaries between cells. Those ESC-derived hepatic cells expressed endodermal and liver specific genes mRNA--TTR, AAT, AFP, ALB, G6P and TAT. ICG uptake assay and PAS reaction were positive for those ESC-derived hepatic cells. The ICG positive cells were about 85.1% in number.

CONCLUSIONESC-derived hepatic cells possess characteristics of hepatocytes, which would promise the eventual clinical use of ESC in treating damaged liver tissues.

Animals ; Cell Differentiation ; physiology ; Cells, Cultured ; Cytokines ; pharmacology ; Embryo, Mammalian ; Fibroblast Growth Factor 1 ; pharmacology ; Hepatocyte Growth Factor ; pharmacology ; Hepatocytes ; cytology ; Mice ; Oncostatin M ; Stem Cells ; cytology

OBJECTIVETo explore the effect of tacrolimus on murine hair follicle cycle.

METHODHematoxylin-eosin dyeing and reverse transcription-polymerase chain raction techniques were used.

RESULTSFive days after depilation, the hair follicles in both the tacrolimus group and the minoxidil group was in anagen V, while that in the vaseline group was in anagen III. vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were detected in back skin in both the tacrolimus group and the minoxidil group, but not in the vaseline group.

CONCLUSIONTacrolimus can promote the growth of hair by stimulating the hair follicle to enter anagen V in mice, which may be explained by the effects of VEGF and HGF.

Animals ; Hair Follicle ; drug effects ; physiology ; Hepatocyte Growth Factor ; metabolism ; Mice ; Mice, Inbred C57BL ; Minoxidil ; pharmacology ; Skin ; drug effects ; metabolism ; Tacrolimus ; pharmacology ; Vascular Endothelial Growth Factor A ; metabolism

OBJECTIVETo evaluate the effects of hepatocyte growth factor (HGF) on the prevention of scar formation and the promotion of wound healing by gene transfer.

METHODSA total of 12 female New Zealand rabbits were used in this study. Rabbits were anesthetized with an intravenous injection of sodium pentobarbital, and identical wounds were made over the ventral surface of each ear. Five circular wounds, 7 mm in diameter, were created in each ear by excision through the skin to the underlying cartilage using sterile technique. After the surgical procedures, 10 of the rabbits were randomly allocated to five groups, with 2 rabbits in each group: Ad-HGF group 1, Ad-HGF group 2, Ad-HGF group 3, Ad-GFP (a reporter gene) group and the solvent group. Immediately after surgery, 6 x 10(7) pfu Ad-HGF, 6 x 10(8) pfu Ad-HGF, 6 x 10(9) pfu of Ad-HGF, 6 x 10(9) pfu of Ad-GFP, or same volume of solvent (PBS, pH 7.2) was applied once to each wound in groups 1 to 5, respectively. One additional rabbit was used to evaluate the transfer efficiency of the adenovirus vector by transferring Ad-GFP (6 x 10(9) pfu) into its wounds. Ice slides of wounds from this animal were observed under fluorescence microscopy. Another additional rabbit was used to evaluate the expression of HGF and TGFbeta1 after transferring Ad-HGF (6 x 10(9) pfu) into each of its wound. Immunohistochemistry was used for detection.

RESULTSThe effect of HGF on reducing excessive dermal scarring was observed by adenovirus-mediated gene transfer. Transfection of the human HGF cDNA into skin wounds through an adenoviral vector suppressed the over-expression of TGFbeta1, which plays an essential role in the progression of dermal fibrogenesis. Application of HGF to the wounds significantly enhanced wound healing and inhibited over scarring.

CONCLUSIONHGF gene therapy could be a new approach for preventing excessive dermal scarring in wound healing.

Animals ; Cicatrix ; prevention & control ; Female ; Gene Transfer Techniques ; Hepatocyte Growth Factor ; pharmacology ; Rabbits ; Random Allocation ; Wound Healing ; drug effects ; physiology

The aim of this study was to investigate the feasibility of the human cord blood adult stem cells (ASCs) to differentiate into hepatocytes in vitro induced by combined stimulation with hepatocyte growth factor (HGF), stem cell factor (SCF) and leukemia inhibitory factor (LIF). The adult stem cells were obtained through density gradient centrifugation and magnetic activated cell sorting (MACS). The adult stem cells were cultured in DMEM with HGF (10 ng/ml)+SCF (10 ng/ml)+LIF (10 ng/ml) in induced group I. In induced group II the enriched cells were cultured in DMEM with SCF (10 ng/ml)+LIF (10 ng/ml) and the undifferentiated cells acted as the control group without the factors. The morphology of cells was observed by the inverted phase contrast microscopy; the expression of albumin (Alb), human hepatocyte cytokeratin (CK18) and alpha-fetoprotein (AFP) were detected by immunofluorescence, immunohistochemistry and RT-PCR assay in the 21-day culture. Alb secreted by hepatocytes in the medium was determined by radioimmunoassay (RIA) at day 7, 14, 21, 23 and 25. The results showed that the shapes of ASCs changed and their sizes and number increased in the course of culture in group I. After being induced for three weeks, the cells turned round and resembled hepatocyte-like cells. The mRNA for Alb could be detected by RT-PCR in the differentiated adult stem cells in group I, and the mRNA for AFP was poorly detected by RT-PCR at day 21. Alb and CK18 were positive through immunofluorescence and immunohistochemistry at day 21, compared with group II and the control group. In group I, Alb in the medium significantly increased, compared with control group, and reached the highest level at day 21, then decreased at day 23. It is concluded that under some definite inducing conditions, human cord blood adult stem cells can differentiate into hepatocyte-like cells and HGF plays a critical role during the course.
Adult Stem Cells ; cytology ; Cell Differentiation ; physiology ; Cells, Cultured ; Fetal Blood ; cytology ; Hepatocyte Growth Factor ; pharmacology ; Hepatocytes ; cytology ; Humans ; Leukemia Inhibitory Factor ; pharmacology

OBJECTIVELiver development needs a number of growth factors and components of the extracellular matrix. The study is to explore how growth factors and extracellular matrix regulate proliferation and differentiation of fetal liver progenitor cell.

METHODSWe demonstrate isolation of hepatic progenitor/stem cells from ED 14.5 SD rat liver, which contains a large number of hepatoblasts. Proliferation assay-3H thymidine incorporation was used to detect the effect of growth factors on proliferation of hepatic progenitor cell. Growth factor and extracellular matrix were added and stem cell clone formation was counted. Mark of bile duct and hepatocyte were detected with double-marker immunocytochemistry.

RESULTSProgenitor liver cells displayed clonogenic capacity, expressed markers of hepatocytes and bile duct cells and G-6-P. HGF, EGF can accelerate DNA synthesis and stem cell clone formation of hepatic progenitor cell. Extracellular matrix collagen I, collagen IV or laminin were essential for formation of stem cell clone. Single cell culture needed HGF, EGF, extracellular matrix and supernatant of mix cell (which contained fetal parenchymal cells, mesenchymal cells and hematopoietic cells) culture.

CONCLUSIONGrowth factors especially HGF and EGF play crucial role in proliferation and differentiation of liver progenitor cell. Some factors secreted from mesenchymal cell and hematopoietic cells may be involved.

Animals ; Cell Differentiation ; drug effects ; Cell Division ; physiology ; Cells, Cultured ; Epidermal Growth Factor ; pharmacology ; Extracellular Matrix ; physiology ; Female ; Fetus ; Hepatocyte Growth Factor ; pharmacology ; Liver ; cytology ; drug effects ; Pregnancy ; Rats ; Rats, Sprague-Dawley ; Stem Cells ; cytology ; drug effects

OBJECTIVETo observe the expression pattern of albumin during the hepatocyte differentiation by human bone marrow stem cells in vitro.

METHODSHuman bone marrow cells were harvested and cultured in the presence of hepatocyte growth factor (HGF), fibroblast growth factor (FGF) and lymphocyte inhibitory factor (LIF). Cells were stained immunohistochemically by albumin specific antibody and examined under a confocal microscope. Supernatant albumin level was measured biochemically on a serial time points of the culture.

RESULTSBy this condition, the attached cells became mature morphologically in 1 week of culture. Hepatocyte-specific albumin could be detected in mature cells. The albumin level revealed a time-dependent change during a 4-week culture.

CONCLUSIONHuman bone marrow cells could be induced to differentiate to mature hepatocytes that produce and secret albumin in vitro. These cells may contribute to a stable source of hepatocytes for clinical hepatocyte transplantation and artificial liver support system.

Albumins ; biosynthesis ; Bone Marrow Cells ; cytology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Culture Media, Conditioned ; pharmacology ; Fibroblast Growth Factors ; pharmacology ; Hepatocyte Growth Factor ; pharmacology ; Hepatocytes ; cytology ; Humans ; Mesenchymal Stromal Cells ; cytology ; physiology

BACKGROUNDColon cancer is one of the major malignancies worldwide and it still remains resistant to much of the currently available chemotherapy. Downregulation of HGF/c-Met signaling pathway is an emerging therapy for cancer treatment.

METHODSIn this study, the inhibitory effects of c-Met phosphorylation were observed with SU11274 on different colon cancer cell lines in vitro.

RESULTSThe results revealed the significant inhibitory effects of SU11274 on cell proliferation and cell survival, in a time and dose-dependent manner. Furthermore, the inhibitory effects of SU11274 on different subgroups of colon cancer cells via the HGF/c-Met signaling pathway were implicated in this study.

CONCLUSIONThe results suggested the possible selective therapeutic effects of c-Met inhibitor on colon cancer.

Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colonic Neoplasms ; drug therapy ; pathology ; Hepatocyte Growth Factor ; pharmacology ; Humans ; Indoles ; pharmacology ; Piperazines ; pharmacology ; Proto-Oncogene Proteins c-met ; antagonists & inhibitors ; physiology ; Signal Transduction ; Sulfonamides ; pharmacology

The Met tyrosine kinase receptor is a widely expressed molecule, which mediates pleiotropic cellular responses following activation by its ligand, hepatocyte growth factor/scatter factor (HGF/SF). Previously, one of the authors identified an alternatively spliced form of Met (Met-SM) that lacked a single exon of a 47-amino-acid segment in the juxtamembrane domain. Here we report that Met-SM is a potent transforming gene in NIH3T3 mouse fibroblast cells. Met-SM-transfected NIH3T3 cells show stronger foci-forming activity than wild type-Met-transfected ones. In addition, Met-SM-transfected NIH3T3 cells form colonies in soft agar and are tumorigenic in athymic nu/nu mice. Furthermore, HGF/SF significantly increases the focus-forming activity of Met-SM comparing to wild type Met. The amount of protein and of tyrosine kinase activity of Met-SM accumulates to a high level following HGF/SF treatment. The accumulation of Met-SM correlated well with its delayed ubiquitination and increased stability. These results are consistent with the important role of the juxtamembrane domain in protein stability of Met receptor and suggest that the alternatively-spliced form may contribute to the development and progression of human cancer.
Proto-Oncogene Proteins c-met/*metabolism/*physiology ; Protein Isoforms/metabolism/physiology ; NIH 3T3 Cells ; Mutant Proteins/metabolism/physiology ; Mice, Nude ; Mice ; Hepatocyte Growth Factor/pharmacology ; Female ; Down-Regulation ; Carcinogens/*metabolism ; Carcinogenicity Tests ; Animals ; *Alternative Splicing

BACKGROUNDVascular endothelial growth factor plays a key role in human colorectal carcinoma invasion and metastasis. However, the regulation mechanism remains unknown. Recent studies have shown that several cytokines can regulate the expression of vascular endothelial growth factor in tumor cells. In this study, we investigated whether hepatocyte growth factor can regulate the expression of vascular endothelial growth factor in colorectal carcinoma cells.

METHODSHepatocyte growth factor and vascular endothelial growth factor in human serum were measured by ELISA. The mRNA level of vascular endothelial growth factor was analyzed by reverse transcription-PCR. Western blot assay was performed to evaluate levels of c-Met and several other proteins involved in the MAPK and PI3K signaling pathways in colorectal carcinoma cells.

RESULTSSerum hepatocyte growth factor and vascular endothelial growth factor were significantly increased in colorectal carcinoma subjects. In vitro extraneous hepatocyte growth factor markedly increased protein and mRNA levels of vascular endothelial growth factor in colorectal carcinoma cells. Hepatocyte growth factor induced phosphorylation of c-Met, ERK1/2 and AKT in a dose-dependent manner. Specific inhibitors on MEK and PI3K inhibited the hepatocyte growth factor-induced expression of vascular endothelial growth factor in colorectal carcinoma cells.

CONCLUSIONThis present study indicates that hepatocyte growth factor upregulates the expression of vascular endothelial growth factor in colorectal carcinoma cells via the MEK/ERK and PI3K/AKT signaling pathways.

Butadienes ; pharmacology ; Cell Line, Tumor ; Chromones ; pharmacology ; Colorectal Neoplasms ; metabolism ; pathology ; Gene Expression Regulation ; drug effects ; Hepatocyte Growth Factor ; blood ; pharmacology ; Humans ; MAP Kinase Signaling System ; physiology ; Morpholines ; pharmacology ; Nitriles ; pharmacology ; Phosphatidylinositol 3-Kinases ; physiology ; Phosphorylation ; Proto-Oncogene Proteins c-met ; metabolism ; RNA, Messenger ; analysis ; Signal Transduction ; physiology ; Vascular Endothelial Growth Factor A ; genetics

Hepatocyte growth factor (HGF) pretreatment could protect multiple cell types from apoptosis induced by various damages including oxidative stress. The present study was designed to investigate the protective effect of HGF on rat cortical neurons against apoptosis induced by hydrogen peroxide (H2O2) in culture, and then to explore whether HGF could influence the mitochondrial pathway of apoptosis. Primary rat cortical neurons were isolated from Sprague-Dawley rats and cultured in serum free medium containing 2% B27 and Neurobasal-A. To mimic the oxidative stress damage, cortical neurons were exposed to 100 mumol/L H2O2 for 4 h. To explore the effects of HGF on the neurons subjected to H2O2 injury, cells were pretreated with HGF 15, 30, 60 ng/mL for 24 h, respectively, and then exposed to 100 mumol/L H2O2 for 4 h. The cell viability was measured by MTT colorimetric assay and cell injury was evaluated by lactate dehydrogenase (LDH) leakage rate. Apoptotic cells were detected by Hoechst 33258 staining and Annexin V-FITC/PI double labeled flow cytometry. The caspase-3 activity was assessed by colorimetry. The alteration of transmembrane potential of mitochondria was determined by confocal laser scanning microscopy. The expression of cytochrome C protein was measured by Western blot analysis. The results showed that H2O2 treatment significantly decreased the cell viability, increased LDH leakage rate and the percentage of apoptotic cells. Pretreatment of HGF at different concentrations (15-60 ng/mL) could remarkably increase the cell viability of neurons. Compared with that of H2O2 group (53.4%+/-7.4%), the cell viabilities of neurons treated with 15, 30, and 60 ng/mL HGF significantly increased to (69.3+/-6.4)%, (77.5+/-6.1)% and (82.9+/-9.3)% (P<0.05), respectively. HGF preincubation also evidently decreased the LDH leakage rate in cortical neurons damaged by H2O2. The results of Hoechst staining revealed that HGF pretreatment could significantly reduce the apoptotic rate of neurons. The apoptotic rate of H2O2 group was (62.8+/-7.1)%, while that of HGF groups decreased significantly to (34.8+/-8.4)%, (23.5+/-3.2)% and (18.6+/-4.5)% (P<0.05), respectively. The data from caspase-3 activity assay indicated that HGF preconditioning could also remarkably decrease the caspase-3 activity of neurons. In addition, in the presence of various concentrations of HGF, the decrease of transmembrane potential of mitochondria in neurons caused by H2O2 injury could be reversed. Moreover, as detected by Western blot analysis, HGF downregulated the expression of cytochrome C protein in neurons. These results suggest that HGF has a protective effect on rat cortical neurons against apoptosis induced by H2O2, which might be related to the inhibition of the mitochondrial apoptotic pathway and the suppression of the caspase-3 activity.
Animals ; Apoptosis ; Brain ; cytology ; Caspase 3 ; metabolism ; Cell Survival ; Cells, Cultured ; Cytochromes c ; metabolism ; Hepatocyte Growth Factor ; pharmacology ; Hydrogen Peroxide ; pharmacology ; Mitochondria ; physiology ; Neurons ; cytology ; drug effects ; Oxidative Stress ; Rats ; Rats, Sprague-Dawley