Priming with a Combination of FGF2 and HGF Restores the Impaired Osteogenic Differentiation of Adipose-Derived Stem Cells.

Classical aging-associated diseases include osteoporosis, diabetes, hypertension, and arthritis. Osteoporosis causes the bone to become brittle, increasing fracture risk. Among the various treatments for fractures, stem cell transplantation is currently in the spotlight. Poor paracrine/differentiation capacity, owing to donor age or clinical history, limits efficacy. Lower levels of fibroblast growth factor 2 (FGF2) and hepatocyte growth factor (HGF) are involved in cell repopulation, angiogenesis, and bone formation in the elderly ADSCs (ADSC-E) than in the young ADSCs (ADSC-Y). Here, we study the effect of FGF2/HGF priming on the osteogenic potential of ADSC-E, determined by calcium deposition in vitro and ectopic bone formation in vivo. Age-induced FGF2/HGF deficiency was confirmed in ADSCs, and their supplementation enhanced the osteogenic differentiation ability of ADSC-E. Priming with FGF2/HGF caused an early shift of expression of osteogenic markers, including Runt-related transcription factor 2 (Runx-2), osterix, and alkaline phosphatase (ALP) during osteogenic differentiation. FGF2/HGF priming also created an environment favorable to osteogenesis by facilitating the secretion of bone morphogenetic protein 2 (BMP-2) and vascular endothelial growth factor (VEGF). Bone tissue of ADSC-E origin was observed in mice transplanted with FGF/HGF-primed ADSC-E. Collectively, FGF2/HGF priming could enhance the bone-forming capacity in ADSC-E. Therefore, growth factor-mediated cellular priming can enhance ADSC differentiation in bone diseases and thus contributes to the increased efficacy in vivo.

Restoration of erectile function by a combination of antiapoptosis by JNK inhibitor and preservation of smooth muscle or endothelium by hepatocyte growth factor in a rat model of cavernous nerve injury.

BACKGROUND: Because of structural alterations in the corpus cavernosum after radical prostatectomy (RP), post-RP erectile dysfunction remains a very difficult condition to treat. We aimed to determine if the combined administration of a Jun-amino terminal kinase (JNK) inhibitor and hepatocyte growth factor (HGF) in the immediate post-injury period would restore erectile function by antiapoptotic and pro-regenerative effects through the rectification of molecular pathways related to the structural integrity of the penis in a rat model of bilateral cavernosal nerve crush injury (CNCI). METHODS: A total of 70 rats were divided into five groups: Sham surgery (S), CNCI (I), and once-daily intraperitoneal administration of 10.0 mg/kg JNK inhibitor + twice-weekly intracavernosal administration of low-dose (2.1 µg), medium-dose (4.2 µg), or high-dose (8.4 µg) HGF (I + J + LH or I + J + MH or I + J + HH, respectively) in the immediate post-injury period. Erectile responses to electrostimulation (1.0, 3.0, and 5.0 V), histological staining, caspase-3 activity, and Western blotting were evaluated 9 days after surgery. RESULTS: Group I showed lower intracavernosal pressure (ICP)/mean arterial pressure (MAP) after stimulation at each voltage, lower area under the curve (AUC)/MAP after stimulation at each voltage, less smooth muscle (SM) content, a lower SM/collagen ratio, higher caspase-3 activity, increased cJun phosphorylation, decreased protein expression of PECAM-1, decreased cMet phosphorylation, and decreased endothelial nitric oxide synthase (eNOS) phosphorylation compared to Group S. The SM content, SM/collagen ratio, protein expression of ICP/MAP, or AUC/MAP after stimulation at each voltage in Group I + J + LH were partially restored, despite the normalization of cJun phosphorylation and caspase-3 activity. The ICP/MAP, AUC/MAP, caspase-3 activity, SM content, protein expression of PECAM-1, cJun phosphorylation, cMet phosphorylation, and eNOS phosphorylation in both Groups I + J + MH and I + J + HH were restored to the levels observed in Group S, while the SM/collagen ratio was significantly improved but not completely normalized. CONCLUSIONS: Our data indicated that the combined administration of a JNK inhibitor and medium or high-dose HGF to nerve-injured rats in the immediate post-injury period after CNCI may restore erectile function to a level comparable to the normal level by suppressing cavernosal apoptosis and preserving the integrity of SM or endothelium via rectification of the cJun and cMet/eNOS pathways.

Combination Therapy with a JNK Inhibitor and Hepatocyte Growth Factor for Restoration of Erectile Function in a Rat Model of Cavernosal Nerve Injury: Comparison with a JNK Inhibitor Alone or Hepatocyte Growth Factor Alone.

We determined if combined administration of JNK-inhibitors and HGF (hepatocyte-growth-factor) would restore erectile-function through both antiapoptotic and regenerative effects in a rat model of cavernous-nerve-crush-injury (CNCI), and compared the results with administration of JNK-inhibitor alone or HGF alone. We randomized 70 rats into 5 groups: sham-surgery-group (S), CNCI (I) group, a group treated with once-daily intraperitoneal-administration of 10.0-mg/kg of JNK-inhibitors (J), a twice-weekly intracavernosal-administration of 4.2-µg HGF group (H), and a combined-treatment with 10.0-mg/kg JNK-inhibitors and 4.2-µg HGF group (J+H). We investigated erectile-responses to electrostimulation, histological-staining, caspase-3-activity-assay, and immunoblotting at two-weeks postoperatively. The three treatment groups showed improvements in erectile-responses (ICP/MAP and AUC/MAP ratios) compared to Group-I. The erectile-responses in Group-J+H were greater than those in Group-J or Group-H. The erectile-responses in Group-J+H were generally normalized. Caspase-3-activity and cJun-phosphorylation in Group-J and Group-J+H improved compared to Group-I, whereas caspase-3-activity in Group-H partially improved. Protein-expression of PECAM-1, eNOS-phosphorylation, and smooth-muscle content in Group-J+H were normalized, although those in Group-J or Group-H were partially restored. Combination therapy with JNK-inhibitors and HGF can generally normalize erectile-function through anti-apoptosis and preservation of endothelium or SM in rat CNCI model. The combined treatment appears to be superior to the respective agent alone in terms of therapeutic effects.

Adrenergic receptor agonists induce the differentiation of pluripotent stem cell-derived hepatoblasts into hepatocyte-like cells.

Current induction methods of hepatocytes from human induced pluripotent stem cells (hiPSCs) are neither low cost nor stable. By screening a chemical library of 1,120 bioactive compounds and known drugs, we identified the α1-adrenergic receptor agonist methoxamine hydrochloride as a small molecule that promotes the differentiation of hiPSC-derived hepatoblasts into ALBUMIN+ hepatocyte-like cells. Other α1-adrenergic receptor agonists also induced the differentiation of hepatocyte-like cells, and an α1-receptor antagonist blocked the hepatic-inducing activity of methoxamine hydrochloride and that of the combination of hepatocyte growth factor (HGF) and Oncostatin M (OsM), two growth factors often used for the induction of hepatoblasts into hepatocyte-like cells. We also confirmed that treatment with methoxamine hydrochloride activates the signal transducer and activator of transcription 3 (STAT3) pathway downstream of IL-6 family cytokines including OsM. These findings allowed us to establish hepatic differentiation protocols for both mouse embryonic stem cells (mESCs) and hiPSCs using small molecules at the step from hepatoblasts into hepatocyte-like cells. The results of the present study suggest that α1-adrenergic agonists induce hepatocyte-like cells by working downstream of HGF and OsM to activate STAT3.

Yi Guan Jian decoction may enhance hepatic differentiation of bone marrow­derived mesenchymal stem cells via SDF­1 in vitro.

A previous study reported that Yi Guan Jian (YGJ) may increase the proliferation and differentiation of hepatic oval cells in a rat liver cirrhosis model. The aim of the present study was to investigate the effect and mechanism of action of YGJ on inducing hepatic differentiation in bone marrow­derived mesenchymal stem cells (BM­MSCs) via stromal­cell derived factor­1 (SDF­1). Murine BM­MSCs were isolated with whole bone marrow adherence, then identified by immunocytochemical staining and flow cytometry. Passage 2 cells were divided into 8 groups and their differentiation was induced by cell factors added to the medium, including hepatocyte growth factor (HGF), SDF­1 and YGJ. Each of the cell factors was used alone and any two or three of them were combined to establish different cell microenvironments in the different treatment groups. Albumin (ALB) was selected as a hepatocellular marker and cytokeratin­18 (CK­18) as a cholangiocellular marker. The protein and mRNA expression levels of ALB and CK­18 were used to determine the differentiation of BM­MSCs using immunocytochemical staining, western blotting and reverse transcription­quantitative polymerase chain reaction on days 7, 14, 21 and 28 during induction. The relative expression levels of ALB and CK­18 resulted in time­dependent increases in the groups supplemented only with HGF, SDF­1 or YGJ. Combination treatment of any two HGF, SDF­1 and YGJ led to a higher expression of ALB and CK­18 compared with only one cell factor treatment. Additionally, when all three were used in a combined treatment the expression levels of ALB and CK­18 occurred at an earlier time and was higher overall. Therefore, the present study suggested that YGJ had an effect on inducing hepatic differentiation in BM­MSCs via SDF­1 and may act in a synergistic manner with HGF and SDF­1.

Oncostatin M in William's E medium is suitable for initiation of hepatocyte differentiation in human induced pluripotent stem cells.

William's E (WE) is a suitable medium for the differentiation of human induced pluripotent stem (iPS) cells to the hepatocyte lineage. The aim of the present study was to investigate various growth factors in their ability to promote hepatocyte differentiation of iPS cells in WE medium. Human iPS 201B7 cells were cultured in WE medium supplemented with growth factors, and mRNA expression levels and promoter activities of α­fetoprotein (AFP) and albumin were examined by reverse transcription­quantitative polymerase chain reaction and luciferase assay, respectively. In addition, time course analysis of AFP mRNA expression was performed in 201B7 cells cultured in WE medium supplemented with oncostatin M. The results demonstrated that mRNA expression levels of AFP were significantly elevated by most growth factors tested as supplements in WE medium, except all­trans retinoic acid, compared with cells cultured in ReproFF (a medium that maintains pluripotency). The highest increase in AFP mRNA expression levels was observed by oncostatin M stimulation. Albumin mRNA expression levels were increased by all­trans retinoic acid and insulin­transferrin­selenium supplementation in WE medium compared with cells cultured in ReproFF. Oncostatin M supplementation significantly stimulated the promoter activity of the AFP gene, but no growth factor tested significantly stimulated the promoter activity of the albumin gene. By time course analysis, significant increase of AFP mRNA expression was observed on the sixth day post­stimulation, compared with cells cultured in WE medium alone. In conclusion, the present study demonstrated that oncostatin M supplementation in WE medium was sufficient to initiate hepatocyte differentiation in iPS cells.

Effect of Yi Guan Jian decoction on differentiation of bone marrow mesenchymalstem cells into hepatocyte-like cells in dimethylnitrosamine-induced liver cirrhosis in mice.

Yi Guan Jian decoction (YGD) may induce the differentiation of bone marrow mesenchymal stem cells (BMSCs) into hepatocyte-like cells (HLCs); however, the underlying mechanisms remain to be elucidated. The present study aimed to investigate this process. To do this, a dimethylnitrosamine (DMN)-induced liver cirrhosis mouse model was established. The mice from the model group were randomly divided into three subgroups: i) Negative control, ii) hepatocyte growth factor and iii) YGD. The overall health, liver function and histological alterations were monitored. The expression of α­smooth muscle actin (α­SMA), C­X­C chemokine receptor type 4 (CXCR4), extracellular signal­regulated kinase (ERK1/2), nuclear factor κB p65 subunit (NF­κB p65) and ß­catenin were measured by immunohistochemistry, western blotting and reverse transcription­quantitative polymerase chain reaction. Following administration of DMN, the overall health of the mice significantly decreased, with an increase in pathological developments and liver damage resulting in a decrease in liver function. Immunohistochemistry revealed that the expression of α­SMA, CXCR4, ERK1/2, NF­κB p65 and ß­catenin was upregulated. Following treatment with YGD, the overall health, liver function and pathology improved. The mRNA and protein expression levels of CXCR4 and ERK1/2 were upregulated, where as α­SMA, NF­κB p65 and ß­catenin levels were downregulated. The results demonstrated that YGD may induce the differentiation of BMSCs into HLCs to reverse DMN­induced liver cirrhosis; this may be achieved via an upregulation of the SDF­1/CXCR4 axis to activate the mitogen activated protein kinase/ERK1/2 signaling pathway.

A stimuli responsive liposome loaded hydrogel provides flexible on-demand release of therapeutic agents.

Lysolipid-based thermosensitive liposomes (LTSL) embedded in a chitosan-based thermoresponsive hydrogel matrix (denoted Lipogel) represents a novel approach for the spatiotemporal release of therapeutic agents. The entrapment of drug-loaded liposomes in an injectable hydrogel permits local liposome retention, thus providing a prolonged release in target tissues. Moreover, release can be controlled through the use of a minimally invasive external hyperthermic stimulus. Temporal control of release is particularly important for complex multi-step physiological processes, such as angiogenesis, in which different signals are required at different times in order to produce a robust vasculature. In the present work, we demonstrate the ability of Lipogel to provide a flexible, easily modifiable release platform. It is possible to tune the release kinetics of different drugs providing a passive release of one therapeutic agent loaded within the gel and activating the release of a second LTSL encapsulated agent via a hyperthermic stimulus. In addition, it was possible to modify the drug dosage within Lipogel by varying the duration of hyperthermia. This can allow for adaption of drug dosing in real time. As an in vitro proof of concept with this system, we investigated Lipogels ability to recruit stem cells and then elevate their production of vascular endothelial growth factor (VEGF) by controlling the release of a pro-angiogenic drug, desferroxamine (DFO) with an external hyperthermic stimulus. Initial cell recruitment was accomplished by the passive release of hepatocyte growth factor (HGF) from the hydrogel, inducing a migratory response in cells, followed by the delayed release of DFO from thermosensitive liposomes, resulting in a significant increase in VEGF expression. This delayed release could be controlled up to 14days. Moreover, by changing the duration of the hyperthermic pulse, a fine control over the amount of DFO released was achieved. The ability to trigger the release of therapeutic agents at a specific timepoint and control dosing level through changes in duration of hyperthermia enables sequential multi-dose profiles. STATEMENT OF SIGNIFICANCE: This paper details the development of a heat responsive liposome loaded hydrogel for the controlled release of pro-angiogenic therapeutics. Lysolipid-based thermosensitive liposomes (LTSLs) embedded in a chitosan-based thermoresponsive hydrogel matrix represents a novel approach for the spatiotemporal release of therapeutic agents. This hydrogel platform demonstrates remarkable flexibility in terms of drug scheduling and sequencing, enabling the release of multiple agents and the ability to control drug dosing in a minimally invasive fashion. The possibility to tune the release kinetics of different drugs independently represents an innovative platform to utilise for a variety of treatments. This approach allows a significant degree of flexibility in achieving a desired release profile via a minimally invasive stimulus, enabling treatments to be tuned in response to changing symptoms and complications.

Kai-Xin-San, a traditional Chinese medicine formula, induces neuronal differentiation of cultured PC12 cells: Modulating neurotransmitter regulation enzymes and potentiating NGF inducing neurite outgrowth.

ETHNOPHARMACOLOGICAL RELEVANCE: Kai-Xin-San, an ancient formula composed of Ginseng Radix et Rhizoma, Polygalae Radix, Acori Tatarinowii Rhizoma and Poria, was frequently applied for major depression disorders for thousands of years. However, its molecular mechanism has not clearly been investigated. AIM OF THE STUDY: We aimed to reveal the action mechanism of KXS on anti-depression on inducing neuronal differentiation on PC12 cells. MATERIALS AND METHODS: A chemically standardized water extract of KXS was applied onto cultured PC12 cells in determining its effect on neurotransmitter regulation enzymes and neurite outgrowth. RESULTS: Single KXS treatment showed obvious changes in the expression of neurofilament and neurotransmitter regulation enzymes, which in parallel to treatment of nerve growth factor (NGF). Although KXS by itself did not show significant inductive effect on neurite outgrowth of PC12 cells, KXS could potentiate the NGF induced neurite outgrowth. Among the three ratios, K-652 showed the most powerful effect and cAMP-dependent pathway might play the major role. CONCLUSIONS: KXS might exert the anti-depressant-like action of be inducing neuronal differentiation, which supported the clinically usage of this decoction.

Hepatocyte growth factor/c-met promotes proliferation, suppresses apoptosis, and improves matrix metabolism in rabbit nucleus pulposus cells in vitro.

The etiology of intervertebral disc (IVD) degeneration is closely related to apoptosis and extracellular matrix degradation in nucleus pulposus (NP) cells. These defects in NP cells are induced by excessive external stressors such as reactive oxygen species (ROS) and inflammatory cytokines. Recently, hepatocyte growth factor (HGF) has been shown to repair damage in various diseases through anti-apoptotic and anti-inflammatory activity. In this study, we investigated the effects of HGF on NP cell abnormality caused by ROS and inflammatory cytokines by using primary NP cells isolated from rabbit IVD. HGF significantly enhanced the proliferation of NP cells. Apoptosis of NP cells induced by H2 O2 or TNF-α was significantly inhibited by HGF. Induction of mRNA expression of the inflammation mediators cyclooxygenase-2 and matrix metalloproteinase-3 and -9 by TNF-α was significantly suppressed by HGF treatment. Expression of c-Met, a specific receptor for HGF, was confirmed in NP cells and was increased by TNF-α, suggesting that inflammatory cytokines increase sensitivity to HGF. These findings demonstrate that activation of HGF/c-Met signaling suppresses damage caused by ROS and inflammation in NP cells through multiple pathways. We further suggest the clinical potential of HGF for counteracting IVD degradation involved in NP cell abnormalities.

Human skin-derived stem cells as a novel cell source for in vitro hepatotoxicity screening of pharmaceuticals.

Human skin-derived precursors (hSKP) are postnatal stem cells with neural crest properties that reside in the dermis of human skin. These cells can be easily isolated from small (fore) skin segments and have the capacity to differentiate into multiple cell types. In this study, we show that upon exposure to hepatogenic growth factors and cytokines, hSKP acquire sufficient hepatic features that could make these cells suitable in vitro tools for hepatotoxicity screening of new chemical entities and already existing pharmaceutical compounds. Indeed, hepatic differentiated hSKP [hSKP-derived hepatic progenitor cells (hSKP-HPC)] express hepatic progenitor cell markers (EPCAM, NCAM2, PROM1) and adult hepatocyte markers (ALB), as well as key biotransformation enzymes (CYP1B1, FMO1, GSTA4, GSTM3) and influx and efflux drug transporters (ABCC4, ABCA1, SLC2A5). Using a toxicogenomics approach, we could demonstrate that hSKP-HPC respond to acetaminophen exposure in a comparable way to primary human hepatocytes in culture. The toxicological responses "liver damage", "liver proliferation", "liver necrosis" and "liver steatosis" were found to be significantly enriched in both in vitro models. Also genes associated with either cytotoxic responses or induction of apoptosis (BCL2L11, FOS, HMOX1, TIMP3, and AHR) were commonly upregulated and might represent future molecular biomarkers for hepatotoxicity. In conclusion, our data gives a first indication that hSKP-HPC might represent a suitable preclinical model for in vitro screening of hepatotoxicity. To the best of our knowledge, this is the first report in which human postnatal stem cells derived from skin are described as a potentially relevant cell source for in vitro hepatotoxicity testing of pharmaceutical compounds.

Characterization of phenolic constituents from ephedra herb extract.

Nine known compounds: trans-cinnamic acid, catechin, syringin, epicatechin, symplocoside, kaempferol 3-O-rhamnoside 7-O-glucoside, isovitexin 2-O-rhamnoside, herbacetin 7-O-glucoside, and pollenitin B and a new flavonoid glycoside, characterized as herbacetin 7-O-neohesperidoside (1) on the basis of spectroscopic analysis and chemical evidence, were isolated from a traditional crude drug, "Ephedra herb extract". Compound 1 had no effects on HGF-induced motility, whereas herbacetin, which is an aglycone of 1, significantly inhibited it.

Nobiletin attenuates metastasis via both ERK and PI3K/Akt pathways in HGF-treated liver cancer HepG2 cells.

Hepatocyte growth factor (HGF), and its receptor, c-Met activation has recently been shown to play important roles in cancer invasion and metastasis in a wide variety of tumor cells. We use HGF as an invasive inducer of human HepG2 cells to investigate the effect of four flavones including apigenin, tricetin, tangeretin, and nobiletin on HGF/c-Met-mediated tumor invasion and metastasis. Among them, nobiletin markedly inhibited HGF-induced the abilities of the adhesion, invasion, and migration by cell-matrix adhesion assay and transwell-chamber invasion/migration assay under non-cytotoxic concentrations. Data also showed nobiletin inhibited HGF-induced cell scattering and cytoskeleton changed such as filopodia and lamellipodia. Furthermore, nobiletin could inhibit HGF-induced the membrane localization of phosphorylated c-Met, ERK2, and Akt, but not phosphorylated JNK1/2 and p38. Next, nobiletin significantly decreased the levels of phospho-ERK2 and phospho-Akt in ERK2 or Akt siRNA-transfected cells concomitantly with a marked reduction on cell invasion and migration. In conclusion, nobiletin attenuates HGF-induced HepG2 cells metastasis involving both ERK and PI3K/Akt pathways and are potentially useful as anti-metastatic agents for the treatment of hepatoma.

Gene alterations and intestinal mucosal changes following growth factor and omega-3 exposure in a rat model of inflammatory bowel disease.

BACKGROUND: We have previously shown that there is synergism between Hepatocyte Growth Factor (HGF) and Omega-3 (OM-3) enriched feeds using an immunologic model of inflammatory bowel disease (IBD). This combination decreased inflammation and cytokine levels and increased microvascular density and mucosal mass. This study evaluates the gene alterations that occurred using this same model. METHODS: Twenty adult female transgenic HLA-B27 rats were divided into four groups: Group 1: (Regular feeds, IV saline); Group 2: (OM-3 feeds, IV saline); Group 3: (Regular feeds, IV HGF 150 µg/kg/day); Group 4: (OM-3 feeds, IV HGF 150 µg/kg/day). Rats were sacrificed 14 days after pump placement. Bowel was harvested and RNA extracted. Microarray gene chips were used. Statistical analysis was done by analysis of variance using Partek Genomics Suite. Results were significant if fold change was more than 2 or less than -2, with P<0.05. RESULTS: In the ileum, HGF up- or down-regulated 34 genes, while OM-3 affected 60 genes. Together 68 genes were affected. Families with a synergistic effect included Solute Carrier Proteins, ATP Binding Cassette Proteins, and Matrix Metalloproteinases. In the colon, 23 genes were affected by HGF, while 66 genes were affected with OM-3. Combined exposure affected 32 genes, including a synergistic effect on solute carrier proteins, aquaporins, and immunologic factors. CONCLUSIONS: There is a synergistic gene alteration effect of exposure of two (HGF and Omega-3 enriched feeds) agents on bowel mucosa. Of most interest was the synergistic effect on the solute carrier protein family, a previously identified gene family up-regulated in response to intestinal failure.

Potent HGF/c-Met axis inhibitors from Eucalyptus globulus: the coupling of phloroglucinol and sesquiterpenoid is essential for the activity.

Eucalyptin A (1), together with two known compounds 2 and 3 exhibiting potent inhibition on HGF/c-Met axis, was discovered from the fruits of Eucalyptus globulus. 1 possessed an unprecedented carbon framework of phloroglucinol-coupled sesquiterpenoid, and its structure was elucidated by spectroscopic method and ECD calculation. A brief structure-activity relationship discussion indicated that the coupling of a phloroglucinol and a sesquiterpenoid is essential for the activity.

High-purity hepatic lineage differentiated from dental pulp stem cells in serum-free medium.

INTRODUCTION: We have previously differentiated hepatocyte like cells from deciduous tooth pulp stem and extracted third molar pulp stem cells with a protocol that used fetal bovine serum, but it showed high contaminations of nondifferentiated cells. Both the lower purity of hepatically differentiated cells and usage of serum are obstacles for application of cell therapy or regenerative medicine. Objective of this study was to investigate the capacity for and purity of hepatocyte-like differentiation of CD117-positive dental pulp stem cells without serum. METHODS: Mesenchymal cells from human deciduous and extracted third molar pulp were isolated and expanded in vitro. We separated CD117-positive cells by using a magnetic-activated cell sorter. The cells were characterized immunofluorescently by using known stem cell markers. For hepatic differentiation, the media were supplemented with hepatic growth factor, insulin-transferrin-selenium-x, dexamethasone, and oncostatin M. Expression of hepatic markers alpha fetoprotein, albumin, hepatic nuclear factor-4 alpha, insulin-like growth factor-1, and carbamoyl phosphate synthetase was examined immunofluorescently after differentiation. The amount of differentiated cells was assessed by using flow cytometry. Glycogen storage and urea concentration in the medium were defined. RESULTS: Both cell cultures demonstrated a number of cells positive for all tested hepatic markers after differentiation, ie, albumin-positive cells were almost 90% of differentiated deciduous pulp cells. The concentration of urea in the media increased significantly after differentiation. Significant amount of cytoplasmic glycogen storage was found in the cells. CONCLUSIONS: Without serum both cell types differentiated into high-purity hepatocyte-like cells. These cells offer a source for hepatocyte lineage differentiation for transplantation in the future.

A cell-based small molecule screening method for identifying inhibitors of epithelial-mesenchymal transition in carcinoma.

Epithelial Mesenchymal Transition (EMT) is a crucial mechanism for carcinoma progression, as it provides routes for in situ carcinoma cells to dissociate and become motile, leading to localized invasion and metastatic spread. Targeting EMT therefore represents an important therapeutic strategy for cancer treatment. The discovery of oncogene addiction in sustaining tumor growth has led to the rapid development of targeted therapeutics. Whilst initially optimized as anti-proliferative agents, it is likely that some of these compounds may inhibit EMT initiation or sustenance, since EMT is also modulated by similar signaling pathways that these compounds were designed to target. We have developed a novel screening assay that can lead to the identification of compounds that can inhibit EMT initiated by growth factor signaling. This assay is designed as a high-content screening assay where both cell growth and cell migration can be analyzed simultaneously via time-course imaging in multi-well plates. Using this assay, we have validated several compounds as viable EMT inhibitors. In particular, we have identified compounds targeting ALK5, MEK, and SRC as potent inhibitors that can interfere with EGF, HGF, and IGF-1 induced EMT signaling. Overall, this EMT screening method provides a foundation for improving the therapeutic value of recently developed compounds in advanced stage carcinoma.

Hepatocyte growth factor and omega-3-enriched feeds have a synergistic effect on mucosal mass in an animal model of inflammatory bowel disease.

BACKGROUND: Hepatocyte growth factor (HGF) decreases intestinal inflammation and cytokine levels in an animal model of inflammatory bowel disease (IBD). Luminal omega-3 (OM-3) is anti-angiogenic, reduces inflammation, and may decrease symptoms in patients with Crohn's disease. This study evaluates the synergism of HGF and OM-3. METHODS: Twenty adult female transgenic HLA-B27 rats were divided into 4 groups: group 1: regular feeds, IV saline; group 2: OM-3-enriched feeds, IV saline; group 3: regular feeds, IV HGF (150 µg/kg per day); and group 4: OM-3-enriched feeds, IV HGF(150 µg/kg per day). Rats were killed at 14 days after pump placement. Small and large bowel mucosa was harvested, and DNA and protein were extracted and quantified. Statistical analysis was done by analysis of variance with post-hoc Tukey's HSD test. RESULTS: Content of protein and DNA in the ileum were significantly increased by supplementation of HGF (P < .001, P < .01, respectively) alone. OM-3 significantly increased protein content but not DNA (P = .02, P = 0.3, respectively). Combined, they had a synergistic effect greater than either supplement alone (P = .0001, P = .002, respectively). In the colon, HGF and OM-3 did not significantly increase protein or DNA content individually or together. CONCLUSIONS: This is the first demonstration of the synergistic effect of a growth factor (HGF) and a dietary supplement (OM-3) in an immunologic model of IBD.

HGF inhibits TGF-ß1-induced myofibroblast differentiation and ECM deposition via MMP-2 in Achilles tendon in rat.

Both myofibroblast differentiation and extracellular matrix (ECM) deposition are essential components of scar formation in tendons, and hepatocyte growth factor (HGF) is reported to prevent fibrogenic responses in tendons. Matrix metalloproteinases-2(MMP-2) is also involved in the healing process in tendons. Whether HGF protects healed Achilles tendons from injury-induced scar formation and the mechanisms are unknown. Daily for 2 weeks after wounding, except for the non-surgical control group, the Achilles tendons in rats were locally injected with HGF (100 ng 50 µl(-1) per mouse) or phosphate-buffered saline (PBS). Histological examination showed HGF ameliorated disorganized collagen fibers caused by surgical incisions in rats. After transforming growth factor beta-1 (TGF-ß1) induced fibrogenic responses in primary Achilles tendon fibroblasts in rats, HGF treatment for 24 h reduced α-smooth muscle actin (α-SMA) (0.60 ± 0.07-fold, P < 0.05) and type III collagen expression (0.39 ± 0.07-fold, P < 0.05). Moreover, HGF elevated MMP-2 expression (1.23 ± 0.11-fold, P < 0.05). The MMP-2 inhibitor, tissue inhibitors of metalloproteinase-1 (TIMP-1), partially blocked the inhibitory effects of HGF on α-SMA expression (from 0.60 ± 0.07-fold to 0.83 ± 0.07-fold, P < 0.05) and type III collagen expression (from 0.39 ± 0.06-fold to 0.86 ± 0.08-fold, P < 0.05). These results indicate HGF attenuates TGF-ß1-induced fibrogenic responses in Achilles tendon, which was mediated by MMP-2. These results will aid in developing effective therapeutic approaches for the dysfunctional repair in Achilles tendons.

Ron receptor tyrosine kinase activation confers resistance to tamoxifen in breast cancer cell lines.

Although tamoxifen treatment is associated with improved survival in patients with estrogen receptor (ER)-positive breast tumors, resistance remains an important clinical obstacle. Signaling through growth factor signaling pathways, in particular through receptor tyrosine kinases, has been demonstrated to confer tamoxifen resistance in an estradiol-independent manner. The Ron receptor tyrosine kinase, a member of the c-Met family of receptors, is expressed in a number of human epithelial tumors, and elevated expression of Ron is associated with poor prognosis in women with breast cancer. In this report, we evaluated the role of Ron receptor activation in conferring resistance to tamoxifen in human and murine breast cancer cell lines. Activation of Ron by its ligand, hepatocyte growth factor-like protein (HGFL) was associated with partial rescue from tamoxifen-induced growth inhibition in Ron-expressing cell lines. Western analysis revealed that treatment of the T47D human breast cancer cell line with tamoxifen and HGFL was associated with increased phosphorylation of mitogen-activated protein kinase (MAPK) 1/2 and phosphorylation of serine residue 118 of ER. Expression of ER-dependent genes was increased in cells treated with tamoxifen and HGFL by quantitative reverse transcription-polymerase chain reaction. All of these effects were inhibited by treatment with either a Ron-neutralizing antibody or a MEK1 inhibitor, suggesting the specificity of the effect to Ron, and the involvement of the MAPK 1/2 signaling pathway. In summary, these results illustrate a novel connection between the Ron receptor tyrosine kinase and an important mechanism of tamoxifen resistance in breast cancer.