BACKGROUND: Perturbations in bone marrow mesenchymal stem cell (BMSC) differentiation play an important role in steroid-induced osteonecrosis of the femoral head (SONFH). At present, studies on SONFH concentrate upon the balance within BMSC osteogenic and adipogenic differentiation. However, BMSC apoptosis as well as proliferation are important prerequisites in their differentiation. The hedgehog (HH) signaling pathway regulates bone cell apoptosis. Baicalin (BA), a well-known compound in traditional Chinese medicine, can affect the proliferation and apoptosis of numerous cell types via HH signaling. However, the potential role and mechanisms of BA on BMSCs are unclear. Thus, we aimed to explore the role of BA in dexamethasone (Dex)-induced BMSC apoptosis in this study. METHODS: Primary BMSCs were treated with 10 -6 mol/L Dex alone or with 5.0 μmol/L, 10.0 μmol/L, or 50.0 μmol/L BA for 24 hours followed by co-treatment with 5.0 μmol/L, 10.0 μmol/L, or 50.0 μmol/L BA and 10 -6 mol/L Dex. Cell viability was assayed through the Cell Counting Kit-8 (CCK-8). Cell apoptosis was evaluated using Annexin V-fluorescein isothiocyanate/propidium iodide (PI) staining followed by flow cytometry. The imaging and counting, respectively, of Hochest 33342/PI-stained cells were used to assess the morphological characteristics and proportion of apoptotic cells. To quantify the apoptosis-related proteins (e.g., apoptosis regulator BAX [Bax], B-cell lymphoma 2 [Bcl-2], caspase-3, and cleaved caspase-3) and HH signaling pathway proteins, western blotting was used. A HH-signaling pathway inhibitor was used to demonstrate that BA exerts its anti-apoptotic effects via the HH signaling pathway. RESULTS: The results of CCK-8, Hoechst 33342/PI-staining, and flow cytometry showed that BA did not significantly promote cell proliferation (CCK-8: 0 μmol/L, 100%; 2.5 μmol/L, 98.58%; 5.0 μmol/L, 95.18%; 10.0 μmol/L, 98.11%; 50.0 μmol/L, 99.38%, F   =  2.33, P   >  0.05), but it did attenuate the effect of Dex on apoptosis (Hoechst 33342/PI-staining: Dex+ 50.0 μmol/L BA, 12.27% vs. Dex, 39.27%, t  = 20.62; flow cytometry: Dex + 50.0 μmol/L BA, 12.68% vs. Dex, 37.43%, t  = 11.56; Both P  < 0.05). The results of western blotting analysis showed that BA reversed Dex-induced apoptosis by activating the HH signaling pathway, which down-regulated the expression of Bax, cleaved-caspase 3, and suppressor of fused (SUFU) while up-regulating Bcl-2, sonic hedgehog (SHH), and zinc finger protein GLI-1 (GLI-1) expression (Bax/Bcl-2: Dex+ 50.0 μmol/L BA, 1.09 vs. Dex, 2.76, t  = 35.12; cleaved caspase-3/caspase-3: Dex + 50.0 μmol/L BA, 0.38 vs . Dex, 0.73, t  = 10.62; SHH: Dex + 50.0 μmol/L BA, 0.50 vs . Dex, 0.12, t  = 34.01; SUFU: Dex+ 50.0 μmol/L BA, 0.75 vs . Dex, 1.19, t  = 10.78; GLI-1: Dex+ 50.0 μmol/L BA, 0.40 vs . Dex, 0.11, t  = 30.68. All P  < 0.05). CONCLUSIONS BA antagonizes Dex-induced apoptosis of human BMSCs by activating the HH signaling pathway. It is a potential candidate for preventing SONFH.
Humans ; Hedgehog Proteins/metabolism* ; bcl-2-Associated X Protein ; Caspase 3/metabolism* ; Signal Transduction/physiology* ; Apoptosis ; Apoptosis Regulatory Proteins/pharmacology* ; Dexamethasone/pharmacology* ; Mesenchymal Stem Cells/metabolism* ; Bone Marrow Cells

The damage of sweat glands in patients with extensive deep burns results in the loss of thermoregulation, which seriously affects the quality of life of patients. At present, there are many researches on the repair of sweat gland function, but the mechanism of human sweat gland development has not been fully clarified. More and more studies have shown that the cascaded pathways of Wnt/β-catenin, ecto- dysplasin A/ectodysplasin A receptor/nuclear factor-κB, sonic hedgehog, and forkhead box transcription factor jointly affect the development of sweat glands, and it has been reported that the cascaded signaling pathways can be used to achieve the reconstruction of sweat adenoid cells in vitro. This article reviews the signaling pathways that affect the development of sweat glands and their involvement in the reconstruction of sweat adenoid cells in vitro.
Adenoids/metabolism* ; Hedgehog Proteins/metabolism* ; Humans ; Quality of Life ; Signal Transduction ; Sweat/metabolism* ; Sweat Glands/physiology*

The Hedgehog (Hh) signalling pathway is essential for cellular proliferation and differentiation during embryonic development. Gain and loss of function of Hh signalling are known to result in an array of craniofacial malformations. To determine the critical period for Hh pathway antagonist-induced frontal bone hypoplasia, we examined patterns of dysmorphology caused by Hh signalling inhibition. Pregnant mice received a single oral administration of Hh signalling inhibitor GDC-0449 at 100 mg•kg or 150 mg•kg body weight at preselected time points between embryonic days (E)8.5 and 12.5. The optimal teratogenic concentration of GDC-0449 was determined to be 150 mg•kg. Exposure between E9.5 and E10.5 induced frontal bone dysplasia, micrognathia and limb defects, with administration at E10.5 producing the most pronounced effects. This model showed decreased ossification of the frontal bone with downregulation of Hh signalling. The osteoid thickness of the frontal bone was significantly reduced. The amount of neural crest-derived frontal bone primordium was reduced after GDC-0449 exposure owing to a decreased rate of cell proliferation and increased cell death.
Administration, Oral ; Anilides ; pharmacology ; Animals ; Bone Diseases, Developmental ; chemically induced ; Cell Proliferation ; drug effects ; physiology ; Female ; Frontal Bone ; abnormalities ; Hedgehog Proteins ; antagonists & inhibitors ; Limb Deformities, Congenital ; chemically induced ; Mice ; Micrognathism ; chemically induced ; Osteogenesis ; drug effects ; Pregnancy ; Pyridines ; pharmacology ; Signal Transduction ; drug effects

Bone morphogenetic proteins (BMPs) are the largest subfamily of the transforming growth factor-β superfamily, and they play important roles in the development of numerous organs, including the inner ear. The inner ear is a relatively small organ but has a highly complex structure and is involved in both hearing and balance. Here, we discuss BMPs and BMP signaling pathways and then focus on the role of BMP signal pathway regulation in the development of the inner ear and the implications this has for the treatment of human hearing loss and balance dysfunction.
Body Patterning ; Bone Morphogenetic Protein Receptors/physiology* ; Bone Morphogenetic Proteins/physiology* ; Cell Differentiation ; Cochlea/embryology* ; Ear, Inner/embryology* ; Hedgehog Proteins/physiology* ; Humans ; Signal Transduction/physiology* ; Smad Proteins/physiology* ; Vestibule, Labyrinth/embryology* ; Wnt Signaling Pathway

BackgroundThe hedgehog signaling system (HHS) plays an important role in the regulation of cell proliferation and differentiation during the embryonic phases. However, little is known about the involvement of HHS in the malignant transformation of cells. This study aimed to detect the role of HHS in the malignant transformation of human bronchial epithelial (16HBE) cells.

MethodsIn this study, two microfluidic chips were designed to investigate cigarette smoke extract (CSE)-induced malignant transformation of cells. Chip A contained a concentration gradient generator, while chip B had four cell chambers with a central channel. The 16HBE cells cultured in chip A were used to determine the optimal concentration of CSE for inducing malignant transformation. The 16HBE cells in chip B were cultured with 12.25% CSE (Group A), 12.25% CSE + 5 μmol/L cyclopamine (Group B), or normal complete medium as control for 8 months (Group C), to establish the in vitro lung inflammatory-cancer transformation model. The transformed cells were inoculated into 20 nude mice as cells alone (Group 1) or cells with cyclopamine (Group 2) for tumorigenesis testing. Expression of HHS proteins was detected by Western blot. Data were expressed as mean ± standard deviation. The t-test was used for paired samples, and the difference among groups was analyzed using a one-way analysis of variance.

ResultsThe optimal concentration of CSE was 12.25%. Expression of HHS proteins increased during the process of malignant transformation (Group B vs. Group A, F = 7.65, P < 0.05). After CSE exposure for 8 months, there were significant changes in cellular morphology, which allowed the transformed cells to grow into tumors in 40 days after being inoculated into nude mice. Cyclopamine could effectively depress the expression of HHS proteins (Group C vs. Group B, F = 6.47, P < 0.05) and prevent tumor growth in nude mice (Group 2 vs. Group 1, t = 31.59, P < 0.01).

ConclusionsThe activity of HHS is upregulated during the CSE-induced malignant transformation of 16HBE cells. Cyclopamine can effectively depress expression of HHS proteins in vitro and prevent tumor growth of the transformed cells in vivo.

Animals ; Cell Transformation, Neoplastic ; genetics ; metabolism ; Gene Expression Regulation, Neoplastic ; genetics ; physiology ; Hedgehog Proteins ; genetics ; metabolism ; Lab-On-A-Chip Devices ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Microfluidics ; Signal Transduction ; genetics ; physiology ; Smoke ; Smoking ; adverse effects

Hedgehog signaling pathway is a conserved and important signaling pathway involved in proliferation and differentiation of many types of cells. Latest studies have found that Hedgehog signaling pathway may induce MSCs osteoblast differentiation by increasing the expression of the Runx2 and Osx and inhibit MSCs differentiate to adipocyte. Hedgehog signaling pathway may also promote osteoblast proliferation by regulating cyclin. This review summarizes the mechanism that Hedgehog signaling pathway regulates osteoblast differentiation and proliferation,and concludes that Hedgehog signaling pathway can regulate bone metabolism. It might provide new ideas for the treatment of osteoporosis.
Cell Differentiation ; Core Binding Factor Alpha 1 Subunit ; genetics ; physiology ; Hedgehog Proteins ; physiology ; Humans ; Mesenchymal Stromal Cells ; cytology ; Osteoblasts ; cytology ; Osteoporosis ; drug therapy ; etiology ; Signal Transduction ; physiology ; Sp7 Transcription Factor ; Transcription Factors ; genetics ; physiology

Hedgehog (Hh) signaling pathway plays an important role during embryonic development and pattern formation. Disruption of Hh pathway results in various developmental disorders and increasing cancer incidence. Here we provide a comprehensive review of the pathway members, focusing on how mammalian Hh regulates the Gli family of transcription factors through its downstream members, the so-called "canonical signaling pathway". Hh signaling pathway is highly conserved among species, and primary cilia plays an important role as a "signaling center" during vertebrate signal transduction. Further, in the past few years, numerous studies have shown that Hh signal can also be transduced through Gli-independent ways collectively referred to as "non-canonical signaling pathways", which can be subdivided into two modules: (i) those not requiring Smo and (ii) those downstream of Smo that do not require Gli transcription factors. Thus, we review the rapid progress on canonical and non-canonical Hh pathways.
Animals ; Cilia ; physiology ; Hedgehog Proteins ; physiology ; Receptors, G-Protein-Coupled ; physiology ; Signal Transduction ; Transcription Factors ; physiology

This study aimed to compare epithelial cells derived from human embryonic stem cells (hESCs) to human ameloblast-lineage cells (ALCs), as a way to determine their potential use as a cell source for ameloblast regeneration. Induced by various concentrations of bone morphogenetic protein 4 (BMP4), retinoic acid (RA) and lithium chloride (LiCl) for 7 days, hESCs adopted cobble-stone epithelial phenotype (hESC-derived epithelial cells (ES-ECs)) and expressed cytokeratin 14. Compared with ALCs and oral epithelial cells (OE), ES-ECs expressed amelogenesis-associated genes similar to ALCs. ES-ECs were compared with human fetal skin epithelium, human fetal oral buccal mucosal epithelial cells and human ALCs for their expression pattern of cytokeratins as well. ALCs had relatively high expression levels of cytokeratin 76, which was also found to be upregulated in ES-ECs. Based on the present study, with the similarity of gene expression with ALCs, ES-ECs are a promising potential cell source for regeneration, which are not available in erupted human teeth for regeneration of enamel.
Ameloblasts ; physiology ; Amelogenesis ; genetics ; Amelogenin ; analysis ; Bone Morphogenetic Protein 4 ; pharmacology ; Cell Culture Techniques ; Cell Differentiation ; drug effects ; Cell Line ; Cell Lineage ; Embryonic Stem Cells ; drug effects ; physiology ; Epithelial Cells ; drug effects ; physiology ; Fibroblast Growth Factor 8 ; analysis ; Hedgehog Proteins ; analysis ; Homeodomain Proteins ; analysis ; Humans ; Keratins ; analysis ; classification ; Lithium Chloride ; pharmacology ; MSX1 Transcription Factor ; analysis ; Mouth Mucosa ; cytology ; Phenotype ; Regeneration ; physiology ; Skin ; cytology ; Transcription Factors ; analysis ; Tretinoin ; pharmacology

In order to study the effects of exogenous sonic hedgehog (shh) peptide on proliferation, adhesion, migration of endothelial progenitor cells (EPCs) from rat peripheral blood, the mononuclear cells were collected from rat peripheral blood by Ficoll density gradient centrifugation. EPCs were isolated with adherence screening method and cultured in M199 culture medium with the supplement of VEGF and bFGF. The immunohistochemical staining was used to identify cell markers such as CDl33 and VEGFR-2. EPCs were stimulated with exogenous shh peptide of different final concentrations (0.01, 0.1, 1, 10 μg/mL). The proliferation, adhesion and migration of EPCs were detected by MTT chromometry, adhesion test and transwell system, respectively. The results of this study showed that, after 7 days of culture, cells formed clusters, assuming typical cobbles-tone pattern under microscope. After 2 weeks of culture, cells were arranged in cord-like fashion and sometimes grew like "micro-vessels". Immunohistochemical staining showed that the cultured cells were positive for both CD133 and VEGFR-2. The proliferation, adhesion and migration of EPCs could be promoted by endogenous shh peptide at concentrations from 0.1 μg/mL to 10 μg/mL in a concentration-dependent manner. The findings indicate that exogenous shh peptide can enhance EPCs proliferation, adhesion, and migration, which may have a potential value for clinical application.
Animals ; Cell Adhesion ; drug effects ; physiology ; Cell Movement ; drug effects ; physiology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Endothelial Cells ; cytology ; drug effects ; physiology ; Hedgehog Proteins ; administration & dosage ; Hematopoietic Stem Cells ; cytology ; drug effects ; physiology ; Male ; Rats ; Rats, Wistar

OBJECTIVE: To investigate the involvement of transcription factor Foxa2 in cardiac differentiation in P19 embryonal carcinoma cells and its molecular mechanism. METHODS: P19 cells were induced to differentiate into cardiomyocytes by adding dimethyl sulfoxide (DMSO) into the culture medium of their embryoid bodies (EBs). The mRNA levels of pluripotency markers of embryonic pluripotent stem cells, cardiac differentiation related genes, and Foxa2 in the cell samples at different time points of cardiac differentiation were detected by reverse transcription PCR (RT-PCR). Differentiated and mature cardiomyocytes were identified by immunofluorescence. Eukaryotic expression plasmid pCMV-rFoxa2 (rat Foxa2) was transfected into P19 cells, and clonal populations of P19 cells that stably expressed green fluorescence protein (GFP)-rFoxa2 were isolated to enhance the expression levels of Foxa2 in P19 cells. The mRNA and protein levels of pluripotency markers and cardiac differentiation related genes in the above cell samples were detected by RT-PCR and Western blot. The mRNA levels of cardiac differentiation related genes in EBs differentiation system were also examined. RESULTS: P19 cells differentiated into cardiomyocytes in the presence of DMSO, accompanied by stimulated expression of Foxa2. Transfection of pCMV-rFoxa2 plasmids into P19 cells upregulated rFoxa2 expression transiently and activated the transcription of its downstream cardiac inducer Cerberus1 (Cer1). The expression of pluripotency marker Nanog was suppressed and the expression of cardiac inducer Sonic Hedgehog (Shh) was elevated in GFP-rFoxa2 P19 cells. The expression of Cer1 and cardiac muscle marker actin, alpha cardiac muscle 1 (Actc1) was upregulated in EBs of GFP-rFoxa2 P19 cells. CONCLUSION Foxa2 participates in cardiac differentiation in P19 embryonal carcinoma cells. Foxa2 may inhibit Nanog expression and stimulate the expression of Cer1 and Shh directly during cardiac differentiation in P19 cells in the presence of DMSO.
Animals ; Cell Differentiation ; drug effects ; Cell Line ; Cytokines ; Dimethyl Sulfoxide ; pharmacology ; Embryonal Carcinoma Stem Cells ; pathology ; Hedgehog Proteins ; metabolism ; Hepatocyte Nuclear Factor 3-beta ; physiology ; Homeodomain Proteins ; metabolism ; Mice ; Myocytes, Cardiac ; cytology ; Nanog Homeobox Protein ; Proteins ; metabolism ; Transfection