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SUMMARY: Senile osteoporosis is mainly caused by reduced osteoblast differentiation and has become the leading cause of fractures in the elderly worldwide. Natural organics are emerging as a potential option for the prevention and treatment of osteoporosis. This study was designed to study the effect of resveratrol on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in osteoporosis mice. A mouse model of osteoporosis was established by subcutaneous injection of dexamethasone and treated with resveratrol administered by gavage. In vivo and in vitro, we used western blot to detect protein expression, and evaluated osteogenic differentiation of BMSCs by detecting the expression of osteogenic differentiation related proteins, calcium deposition, ALP activity and osteocalcin content. Resveratrol treatment significantly increased the body weight of mice, the level of serum Ca2+, 25(OH)D and osteocalcin, ration of bone weight, bone volume/total volume, trabecular thickness, trabecular number, trabecular spacing and cortical thickness in osteoporosis mice. In BMSCs of osteoporosis mice, resveratrol treatment significantly increased the expression of Runx2, osterix (OSX) and osteocalcin (OCN) protein, the level of calcium deposition, ALP activity and osteocalcin content. In addition, resveratrol treatment also significantly increased the expression of SIRT1, p-PI3K / PI3K and p-AKT / AKT in BMSCs of osteoporosis mice. In vitro, resveratrol increased the expression of SIRT1, p-PI3K / PI3K and p-AKT / AKT, Runx2, OSX and OCN protein, the level of calcium deposition, ALP activity and osteocalcin content in BMSCs in a concentration-dependent manner, while SIRT1 knockdown significantly reversed the effect of resveratrol. Resveratrol can attenuate osteoporosis by promoting osteogenic differentiation of bone marrow mesenchymal stem cells, and the mechanism may be related to the regulation of SIRT1/PI3K/AKT pathway.
La osteoporosis senil es causada principalmente por una diferenciación reducida de osteoblastos y se ha convertido en la principal causa de fracturas en las personas mayores en todo el mundo. Los productos orgánicos naturales están surgiendo como una opción potencial para la prevención y el tratamiento de la osteoporosis. Este estudio fue diseñado para estudiar el efecto del resveratrol en la diferenciación osteogénica de las células madre mesenquimales de la médula ósea (BMSC) en ratones con osteoporosis. Se estableció un modelo de osteoporosis en ratones mediante inyección subcutánea de dexametasona y se trató con resveratrol administrado por sonda. In vivo e in vitro, utilizamos Western blot para detectar la expresión de proteínas y evaluamos la diferenciación osteogénica de BMSC detectando la expresión de proteínas relacionadas con la diferenciación osteogénica, la deposición de calcio, la actividad de ALP y el contenido de osteocalcina. El tratamiento con resveratrol aumentó significativamente el peso corporal de los ratones, el nivel sérico de Ca2+, 25(OH)D y osteocalcina, la proporción de peso óseo, el volumen óseo/ volumen total, el espesor trabecular, el número trabecular, el espaciado trabecular y el espesor cortical en ratones con osteoporosis. En BMSC de ratones con osteoporosis, el tratamiento con resveratrol aumentó significativamente la expresión de las proteínas Runx2, osterix (OSX) y osteocalcina (OCN), el nivel de deposición de calcio, la actividad de ALP y el contenido de osteocalcina. Además, el tratamiento con resveratrol también aumentó significativamente la expresión de SIRT1, p-PI3K/PI3K y p-AKT/AKT en BMSC de ratones con osteoporosis. In vitro, el resveratrol aumentó la expresión de las proteínas SIRT1, p-PI3K/PI3K y p- AKT/AKT, Runx2, OSX y OCN, el nivel de deposición de calcio, la actividad de ALP y el contenido de osteocalcina en BMSC de manera dependiente de la concentración, mientras que La caída de SIRT1 revirtió significativamente el efecto del resveratrol. El resveratrol puede atenuar la osteoporosis al promover la diferenciación osteogénica de las células madre mesenquimales de la médula ósea, y el mecanismo puede estar relacionado con la regulación de la vía SIRT1/PI3K/AKT.
Subject(s)
Animals , Male , Mice , Osteoporosis/drug therapy , Resveratrol/administration & dosage , Osteogenesis/drug effects , Cell Differentiation/drug effects , Blotting, Western , Disease Models, Animal , Sirtuin 1 , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Resveratrol/pharmacology , Mice, Inbred C57BLABSTRACT
Objective@# To explore the effects of red LED light mediated by the Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (KEAP1-NRF2/HO-1) pathway on osteogenic differentiation and oxidative stress damage of human periodontal ligament stem cells (hPDLSCs) induced by high glucose, which provides a basis for the application of red light-emitting diode (LED) light in cell antioxidative damage.@*Methods@#hPDLSCs were identified by flow cytometric analysis, alkaline phosphatase (ALP) staining and Alizarin red-S staining; hPDLSCs were pretreated in a high glucose environment for 48 hours and irradiated with 1, 3, or 5 J/cm2 red LED light. A CCK-8 assay was performed to choose the radiant exposure that had the strongest effect on promoting the cell proliferation rate for subsequent experiments. hPDLSCs were divided into a control group, a high glucose group and a high glucose+light exposure group. ALP staining, ALP activity, Alizarin red-S staining and quantitative calcified nodules were used to detect the osteogenic differentiation of hPDLSCs; qRT-PCR and Western blot were used to detect the gene and protein expression levels of ALP, runt-related transcription factor 2 (RUNX2) and osterix (OSX); the relative mRNA expression levels of antioxidant enzyme-related genes superoxide dismutase 2 (SOD2) and catalase (CAT) in hPDLSCs were detected by qRT-PCR; reactive oxygen species (ROS) levels were detected by fluorescence microscopy and flow cytometry; the tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels in cell supernatants were detected by ELISA; the NRF2-specific inhibitor ML385 was used to inhibit the NRF2 pathway; ALP staining and ALP activity were used to detect the markers of early osteogenic differentiation; qRT-PCR was used to detect the gene expression of ALP, RUNX2 and OSX; and the protein expression levels of KEAP1, NRF2 and HO-1 were detected by Western blot.@*Results @# Identified, and irradiant exposure of 5 J/cm2 was chosen for subsequent experiments. Red LED light irradiation (5 J/cm2) improved the osteogenic differentiation of hPDLSCs induced by high glucose (P<0.05), increased the mRNA and protein levels of ALP, RUNX2 and OSX (P<0.05), upregulated the mRNA expression levels of SOD2 and CAT (P<0.05), reduced the levels of ROS (P<0.05), and reduced TNF-α and IL-1β levels in the cell supernatants (P<0.05). When ML385 was added to inhibit the NRF2 pathway, the ALP activity of cells was decreased (P<0.05); the gene expression levels of ALP, RUNX2 and OSX were downregulated (P<0.05); the protein level of KEAP1 was upregulated (P<0.05); and the protein levels of NRF2 and HO-1 were downregulated (P<0.05)@*Conclusion@#Red LED light may promote the proliferation and osteoblastic differentiation of hPDLSCs induced by high glucose through the KEAP1-NRF2/HO-1 pathway and reduce the oxidative stress damage to hPDLSCs induced by high glucose.
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Objective @#To investigate the role and mechanism of bone formation caused by the ratio of advanced platelet-rich fibrin (A-PRF) and β-tricalcium phosphate (β-TCP) in rabbit femur defect model, which provides a new idea for clinical treatment of bone defect.@*Methods @#Twenty-four New Zealand white rabbits were divided into model group, 1∶1 complex group (A-PRF∶β-TCP=1∶1), 2∶1 complex group (A-PRF∶β- TCP=2∶1) and 4∶1 complex group (A-PRF∶β- TCP=4∶1）, with 6 rabbits in each group. Femoral defect models were constructed in each group. In the composite group, the bone defect was filled with composite material, while in the model group, no material was filled. After 8 weeks, the animals were euthanized and specimens were collected. Bone mineral density (BMD), bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.SP) and trabecular number (Tb.N) in femoral defect tissue were measured by micro-CT and photographed. Hematoxylin - eosin staining was used to detect the pathological changes of new bone tissue. The morphological changes of the new bone tissue were observed by scanning electron microscopy. Determination of phospho-mitogen activated protein kinase p38 (p-p38MAPK), CCAAT/enhancer binding protein homologous protein (CHOP) and phospho-cysteine aspartic protease-3 (p-Caspase3) in newborn femur by ELISA. The mRNA expressions of osteoprotegerin (OPG), bone morphogenetic protein-2 (BMP-2), receptor activator of nuclear factor kappa-B ligand (RANKL) and p38MAPK were detected by real-time quantitative PCR. The expression of OPG, BMP-2, RANKL, p-p38MAPK and p-Caspase3 protein in the new bone tissue was observed by immunohistochemistry. @*Results @#In the model group, bone formation in the femoral defect area was slow and osteogenic quality was poor. Compared with the model group, the bone formation and neocapillaries of femoral defect area in the complex group was good, BMD, BV.TV, Tb.Th, Tb.N were increased, and Tb.Sp were decreased, the expressions of p-p38MAPK, CHOP and p-Caspase3 were decreased, and the mRNA and protein expressions of OPG and BMP-2 were increased. The mRNA expression of RANKL and p38MAPK was decreased. Apoptosis in new bone tissue of each group showed the lowest apoptosis rate in samples of the 2∶1 complex group (P<0.05); A-PRF: β-TCP=2∶1 ratio has the best osteogenic effect. @*Conclusion@#The complex composed of A-PRF and β-TCP can promote the expression of OPG, inhibit the expression of RANKL and phosphorylation of p38MAPK, reduce the apoptosis of new bone tissue cells, and promote osteogenic differentiation.
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This study aimed to investigate the effects of Erxian Decoction(EXD)-containing serum on the proliferation and osteogenic differentiation of MC3T3-E1 cells under oxidative stress through BK channels. The oxidative stress model was induced in MC3T3-E1 cells by H_2O_2, and 3 mmol·L~(-1) tetraethylammonium(TEA) chloride was used to block the BK channels in MC3T3-E1 cells. MC3T3-E1 cells were divided into a control group, a model group, an EXD group, a TEA group, and a TEA+EXD group. After MC3T3-E1 cells were treated with corresponding drugs for 2 days, 700 μmol·L~(-1) H_2O_2 was added for treatment for another 2 hours. CCK-8 assay was used to detect cell proliferation activity. The alkaline phosphatase(ALP) assay kit was used to detect the ALP activity of cells. Western blot and real-time fluorescence-based quantitative PCR(RT-qPCR) were used to detect protein and mRNA expression, respectively. Alizarin red staining was used to detect the mineralization area of osteoblasts. The results showed that compared with the control group, the model group showed significantly blunted cell proliferation activity and ALP activity, reduced expression of BK channel α subunit(BKα), collagen Ⅰ(COL1), bone morphogenetic protein 2(BMP2), osteoprotegerin(OPG), and phosphorylated Akt, decreased mRNA expression levels of Runt-related transcription factor 2(RUNX2), BMP2, and OPG, and declining area of calcium nodules. EXD-containing serum could significantly potentiate the cell proliferation activity and ALP activity, up-regulate the protein expression of BKα, COL1, BMP2, OPG, and phosphorylated Akt, and forkhead box protein O1(FoxO1), promote the mRNA expression of RUNX2, BMP2, and OPG, and enlarge the area of calcium nodules. However, BK channel blockage by TEA reversed the effects of EXD-containing serum in promoting the protein expression of BKα, COL1, BMP2, OPG, and phosphorylated Akt and FoxO1, increasing the mRNA expression of RUNX2, BMP2, and OPG, and enlarging the area of calcium nodules. EXD-containing serum could improve the proliferation activity, osteogenic differentiation, and mineralization ability of MC3T3-E1 cells under oxidative stress, which might be related to the regulation of BK channels and downstream Akt/FoxO1 signaling pathway.
Subject(s)
Osteogenesis , Core Binding Factor Alpha 1 Subunit/pharmacology , Large-Conductance Calcium-Activated Potassium Channels/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Calcium/metabolism , Cell Differentiation , RNA, Messenger/metabolism , Cell Proliferation , OsteoblastsABSTRACT
Periodontitis is a complex chronic inflammatory disease. The invasion of pathogens induces the inflammatory microenvironment in periodontitis. Cell behavior changes in response to changes in the microenvironment, which in turn alters the local inflammatory microenvironment of the periodontium through factors secreted by cells. It has been confirmed that periodontal ligament stem cells (PDLSCs) are vital in the development of periodontal disease. Moreover, PDLSCs are the most effective cell type to be used for periodontium regeneration. This review focuses on changes in PDLSCs, their basic biological behavior, osteogenic differentiation, and drug effects caused by the inflammatory microenvironment, to provide a better understanding of the influence of these factors on periodontal tissue homeostasis. In addition, we discuss the underlying mechanism in detail behind the reciprocal responses of PDLSCs that affect the microenvironment.
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Humans , Periodontal Ligament , Osteogenesis , Stem Cells , Periodontitis/metabolism , Cell Differentiation/physiology , Cells, CulturedABSTRACT
OBJECTIVE@#To investigate the regulatory effects of miR-26a-5p on the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) by regulating cAMP response element binding protein 1 (CREB1).@*METHODS@#The adipose tissues of four 3-4 weeks old female C57BL/6 mice were collected and the cells were isolated and cultured by digestion separation method. After morphological observation and identification by flow cytometry, the 3rd-generation cells were subjected to osteogenic differentiation induction. At 0, 3, 7, and 14 days after osteogenic differentiation induction, the calcium deposition was observed by alizarin red staining, ALP activity was detected, miR- 26a-5p and CREB1 mRNA expressions were examined by real-time fluorescence quantitative PCR, and CREB1 protein and its phosphorylation (phospho-CREB1, p-CREB1) level were measured by Western blot. After the binding sites between miR-26a-5p and CREB1 was predicted by the starBase database, HEK-293T cells were used to conduct a dual-luciferase reporter gene experiment to verify the targeting relationship (represented as luciferase activity after 48 hours of culture). Finally, miR-26a-p inhibitor (experimental group) and the corresponding negative control (control group) were transfected into ADSCs. Alizarin red staining, ALP activity, real-time fluorescent quantitative PCR (miR-26a-5p) and Western blot [CREB1, p-CREB1, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)] were performed at 7 and 14 days after osteogenic induction culture.@*RESULTS@#The cultured cells were identified as ADSCs. With the prolongation of osteogenic induction culture, the number of calcified nodules and ALP activity significantly increased ( P<0.05). The relative expression of miR-26a-5p in the cells gradually decreased, while the relative expressions of CREB1 mRNA and protein, as well as the relative expression of p-CREB1 protein were increased. The differences were significant between 7, 14 days and 0 day ( P<0.05). There was no significant difference in p-CREB1/CREB1 between different time points ( P>0.05). The starBase database predicted that miR-26a-5p and CREB1 had targeted binding sequences, and the dual-luciferase reporter gene experiment revealed that overexpression of miR-26a-5p significantly suppressed CREB1 wild-type luciferase activity ( P<0.05). After 7 and 14 days of osteogenic induction, compared with the control group, the number of calcified nodules, ALP activity, and relative expressions of CREB1, p-CREB1, OCN, and RUNX2 proteins in the experimental group significantly increased ( P<0.05). There was no significant difference in p-CREB1/CREB1 between the two groups ( P>0.05).@*CONCLUSION@#Knocking down miR-26a-5p promoted the osteogenic differentiation of ADSCs by up-regulating CREB1 and its phosphorylation.
Subject(s)
Animals , Female , Mice , Cell Differentiation , Cells, Cultured , Core Binding Factor Alpha 1 Subunit/metabolism , Cyclic AMP Response Element-Binding Protein/metabolism , Mesenchymal Stem Cells , Mice, Inbred C57BL , MicroRNAs/metabolism , Osteocalcin/metabolism , Osteogenesis/genetics , RNA, Messenger/geneticsABSTRACT
Objective @# To investigate the effect of erythropoietin producing hepatocyte kinase receptor ligand B2-erythropoietin producing hepatocyte kinase receptor B4 (EphrinB2/EphB4) on the osteogenic differentiation of MC3T3-E1 cells in a hypoxic environment to provide experimental evidence for hypoxia regulation of osteoblast differentiation.@*Methods @# Control groups and cobalt chloride (CoCl2)-induced hypoxia groups were set up first. qRT-PCR was used to detect the mRNA expression of the osteogenic markers alkaline phosphatase (ALP), collogen1 (COL I), runt-related transcription factor 2 (RUNX2) and osteocalcin (OCN). ALP staining was used to detect the activity of cell alkaline phosphatase after osteogenic induction. The mRNA and protein expression levels of hypoxia inducible factor-1α (HIF-1α), EphrinB2 and EphB4 in the two groups were detected via qRT-PCR and Western blot. Then, the CoCl2 + inhibitor group was established. NVP-BHG712, an EphB4 phosphorylation inhibitor, was added to this group to prevent EphrinB2 from binding to EphB4 and producing signals. qRT-PCR and Western blot were used to detect the mRNA and protein expression of osteogenic markers, including ALP, RUNX2, COL I, and OCN. ALP staining and Alizarin red S staining were used to measure osteoblast differentiation and mineralization. @*Results @# Compared with the control group, the mRNA expression of the osteogenic differentiation markers ALP, RUNX2, COL-1, and OCN in MC3T3-E1 cells increased, and ALP activity and mineralization were enhanced under CoCl2-induced hypoxia in vitro (P<0.05). Additionally, the expression of HIF-1α, EphrinB2 and EphB4 was upregulated at the mRNA and protein levels under hypoxia (P<0.05). When NVP-BHG712 was used to block the connection between EphrinB2 and EphB4, the expression of osteogenic markers and ALP activity and mineralization were decreased (P<0.05).@*Conclusion@#EphrinB2/EphB4 can promote osteogenic differentiation of MC3T3-E1 cells and increase the expression of osteogenic markers and tissue mineralization in a hypoxic environment.
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Bone marrow mesenchymal stem cells （BMSCs） are derived from stem cells isolated from bone marrow and have the potential for multidirectional differentiation and self-renewal. Under certain conditions， BMSCs can be induced to differentiate into osteoblast （OB）， chondrocyte， adipocyte， fibroblast， etc. BMSCs play an important role in maintaining the stability of bone structure and balancing bone metabolism. Promoting the proliferation of BMSCs and inducing their differentiation into OB of great significance for the clinical prevention and treatment of osteoporosis， bone defects， fracture healing， and other diseases. Because the proliferation and osteogenic differentiation of BMSCs are complex processes controlled by multiple genes and regulated by multiple signal transduction pathways， traditional Chinese medicine （TCM） happens to have the advantages of multi-bioactive component， multi-target， and multi-pathway synergism， which can affect the proliferation and differentiation of BMSCs through multiple channels and induce the proliferation of BMSCs. The transcription and expression of genes related to osteogenesis can be enhanced to promote the differentiation of BMSCs into OB， so as to achieve the purpose of preventing and treating osteoporosis， bone defects， and other bone diseases. Based on the literature on the intervention of TCM monomers and compounds in the proliferation and osteogenic differentiation of BMSCs， this study reviewed TCM monomers and compounds in promoting the proliferation and osteogenic differentiation of BMSCs by regulating secreted glycoprotein （Wnt）， neurogenic locus notch homolog protein （Notch）， mitogen-activated protein kinase （MAPK）， phosphatidylinositol-3 kinase （PI3K） /protein kinase B （Akt）， bone morphogenetic protein （BMP）/Smad， Janus kinase （JAK）/signal transducer and activator of transcription protein （STAT）， osteoprotegerin （OPG）/receptor activator of nuclear factor-kappa B （RANK）/RANK ligand （RANKL）， and other signaling pathways to provide new ideas for the research and clinical application of Chinese medicine in the prevention and treatment of orthopedic diseases.
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Context: The proliferation and differentiation of human periodontal ligament stem cells (hPDLSC) into other cell types are also mediated by mechanical stresses; they might offer therapeutic benefits in tissue regeneration and angiogenesis. Objectives: The study was planned to assess the proliferation, clonogenic potential, and osteogenic differentiation of human periodontal ligament stem cells (PDLSC) following the application of light and heavy orthodontic forces. Materials and Methods: A couple forces of 50 gm (light force) were applied on the 1st premolar on the one side and 250 gm (heavy force) on the contralateral side in the upper arch of patients requiring orthodontic treatment with extraction of all 1st premolars. After 30 days, periodontal tissues were scrapped from extracted teeth for the establishment of PDLSC in vitro. PDLC from the lower premolar teeth where no orthodontic force was applied acted as the control group. Morphology, viability, proliferating rate and population doubling time, clonogenicity, and alkaline phosphatase activity were analysed. Result: The osteogenic potential was confirmed by Alizarin red staining and the expression of the osteogenic markers by qRT?PCR. The morphology, growth kinetics, potency, and osteogenic lineage characteristics inferred the application of high force reduced the proliferative ability and osteogenesis of PDLSC, though the difference was not significant. Conclusion: The established PDLSCs demonstrated their MSC?like properties based on morphology, growth kinetics, colony forming ability, and AP activity. The culture?expanded PDLSCs showed their differentiation potential into osteocytes. The application of high force reduced the proliferative ability and osteogenesis of PDLSCs, variations were not significant.differentiation
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Objective:To prepare the hydrogel scaffolds with different concentrations of laponite and compare their osteogenic properties.Methods:The scaffolds of gelatin/sodium alginate hydrogel into which laponite was added according to the mass ratios of 0%, 1%, 2%, and 3% were assigned into groups T0, T1, T2, and T3. In each group, the compressive modulus was measured and the leaching solution for 24 h extracted to measure the ion release. Bone marrow mesenchymal stem cells (BMSCs) were cultured in the extract medium from each group and common medium (blank group) ( n=3) in the in vitro experiments to determine the expression of osteogenic genes Runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP) and type I collagen after 7 days of culture. In the in vivo experiments, the scaffolds were implanted into the femoral condyle defects in rats, and a blank group with no scaffolds was set. The bone repair in each group was evaluated by hematoxylin-eosin(HE) staining and immunohistochemical staining. Results:The compressive modulus in group T2 [(139.05±6.43) kPa] was significantly higher than that in groups T0, T1 and T3 [(68.83±3.76) kPa, (101.18±3.68) kPa and (125.40±3.28) kPa] ( P<0.05). The ion contents of lithium, magnesium and silicon released from the 24 h leaching solution in group T2 were (0.031±0.005) μg/mL, (3.047±0.551) μg/mL and (5.243±0.785) μg/mL, insignificantly different from those in group T3 ( P> 0.05) but significantly larger than those in group T1 ( P>0.05). The in vitro experiments showed that the expression levels of Runx2, ALP and type I collagen in group T2 were 1.59±0.11, 2.02±0.08 and 1.06±0.17, significantly higher than those in the other groups ( P<0.05). HE staining showed that the implanted hydrogel was tightly bound to the bone tissue. Immunohistochemical staining showed that the numbers of Runx2 and osteocalcin positive cells in group T2 were significantly higher than those in the other groups. Conclusions:With ideal biocompatibility, hydrogel scaffolds with different concentrations of laponite can slowly release the decomposed ions of lithium, magnesium and silicon to promote the osteogenic differentiation of BMSCs and the repair of bone defects in vivo. A 2% concentration of laponite in the hydrogel scaffolds may result in the best results.
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Objective@#To explore the effects of long noncoding-RNA (lncRNA) taurine upregulated gene 1 (TUG1) on the proliferation and osteogenic/odontoblast differentiation of human dental pulp stem cells (hDPSCs). @*Methods @# hDPSCs were isolated and cultured. The surface antigens CD44, CD45, CD73, CD90, CD133 and STRO-1 were detected by flow cytometry. Alkaline phosphatase (ALP) staining and alizarin red staining were used to identify the ability of cells to differentiate. RNA was collected on Days 0, 7 and 14 of the osteogenic induction of hDPSCs, and qRT-PCR was used to detect the relative expression of TUG1. The hDPSCs were stably transfected with a lentiviral vector containing the TUG1-silenced pSLenti-U6-shRNA(TUG1)-CMV-EGFP-F2A-Puro-WPRE to silence TUG1. The ability of hDPSCs to proliferate was assessed with the CCK-8 method. ALP and alizarin red staining and quantitative detection were used to detect the ALP activity and formation of mineralized nodules of hDPSCs. The expression levels of dentin sialophosphoprotein (DSPP), dentin matrix protein-1 (DMP-1), Runt-associated transcription factor 2 (Runx2), osteocalcin (OCN) and osteopontin (OPN) genes and proteins were measured by qRT-PCR and Western blot.@*Results @#The hDPSCs were successfully isolated and cultured, and TUG1 expression was significantly increased during osteogenic differentiation (P<0.05). The hDPSCs proliferation was suppressed after silencing TUG1(P<0.05). After osteogenic induction, ALP and alizarin red staining showed that ALP activity and mineralized nodules were suppressed by silencing TUG1. The expression levels of the odontogenic differentiation gene DSPP and DMP-1 and the osteogenic differentiation gene Runx2, OCN and OPN were also significantly decreased (P<0.05).@*Conclusion @# Knocking down TUG1 can inhibit the proliferation and osteogenic/odontogenic differentiation of hDPSCs.
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ObjectiveTo explore the underlying mechanism of Bushen Huatan prescription in alleviating postmenopausal osteoporosis （PMOP） by maintaining the balance of osteogenesis and adipogenic differentiation in ovariectomized rats with osteoporosis. MethodSeventy-five 6-month-old non-pregnant female SD rats were randomly divided into sham-operation group， model group， atorvastatin group， liviol group， and Bushen Huatan prescription group. Bilateral ovaries were removed in the four groups except the sham-operation group， while only the same mass of adipose tissue around the ovaries was removed in the sham-operation group. On the 5th week after surgery， drugs were consecutively administrated for 8 weeks. Rats in the Bushen Huatan prescription group received 9.4 mg·kg-1 of the prescription， rats in the atorvastatin group received 0.92 mg·kg-1 of atorvastatin， rats in the Liviol group received 0.23 mg·kg-1 of liviol， and rats in the model group and the sham-operation group received saline once a day. Micro-computed tomography （Micro CT） was used to detect bone mineral density （BMD） of rat tibia in each group. Hematoxylin-eosin （HE） staining was used to detect the relative area of rat bone marrow adipose tissue （BMAT） in each group. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the relative expression levels of Runt-related transcription factor 2 （Runx2）， peroxisome proliferator-activated receptor （PPARγ）， leptin （LPN）， and leptin receptor （OBR） in bone tissues. ResultAs compared with the sham operation group， the BMD of rats in the model group decreased （P<0.05）， while the relative area of BMAT increased （P<0.05）. In addition， the expression levels of LPN， OBR， and Runx2 decreased in the model group （P<0.05）， while the level of PPARγ increased （P<0.05）. As compared with the model group， the BMD of rats in the atorvastatin group， the Livial group， and the Bushen Huatan prescription group increased （P<0.05）， and the relative area of BMAT decreased （P<0.05）. The expression levels of LPN， OBR， and Runx2 in these groups increased （P<0.05）， while the expression level of PPARγ decreased （P<0.05）. ConclusionBushen Huatan prescription plays the anti-osteoporosis role in the rat model of PMOP through up-regulating LPN and OBR in bone tissues and maintaining the balance of osteogenesis and adipogenic differentiation， thereby reducing postmenopausal bone loss and playing a role in the prevention and treatment of PMOP.
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Abstract Objectives Osteoblasts are derived from Bone Marrow-derived Mesenchymal Stem Cells (BM-MSCs), which play an indispensable role in bone formation. In this study, the authors aim to investigate the role of IRF4 in the osteogenic differentiation of BM-MSCs and its potential molecular mechanism. Methods The authors used lentivirus infection to overexpress IRF4 in BM-MSCs. The expression of IRF4 and osteogenesis-related genes were detected by qRT-PCR and western blot analysis. The osteogenic differentiation of BM-MSCs was evaluated by Alkaline Phosphatase (ALP) activity, Alizarin red staining, and Alkaline Phosphatase (ALP) staining. Chromatin Immunoprecipitation (ChIP), Dual-Luciferase reporter assay and RNA Immunoprecipitation Assay were applied to confirm the regulatory mechanism between IRF4, miR-636 and DOCK9. Results The authors found IRF4 was down-regulated during the osteogenic differentiation of BM-MSCs, and IRF4 overexpression could decrease the osteogenic differentiation of BM-MSCs by specifically promoting the reduction of Alkaline Phosphatase (ALP) activity and down-regulating osteogenic indicators, including OCN, OPN, Runx2 and CollA1. Mechanistically, IRF4 activated microRNA-636 (miR-636) expression via binding to its promoter region, and Dedicator of Cytokinesis 9 (DOCK9) was identified as the target of miR-636 in BM-MSCs. Moreover, the damage in the capacity of osteogenic differentiation of BM-MSCs induced by IRF4 overexpression could be rescued by miR-636 inhibition. Conclusions In summary, this paper proposed that IRF4/miR-636/DOCK9 may be considered as targets for the treatment of osteoporosis (OP).
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@#Metformin is currently the first-line drug for the treatment of diabetes. In addition to its hypoglycemic effect, it has also been found to have other potential effects, such as anti-inflammatory, odontogenic differentiation-promoting, osteogenic differentiation-promoting, and antitumor effects. Previous studies have shown that metformin can promote the healing of periapical lesions, and its mechanism may be related to the promotion of osteogenic differentiation and the induction of dental pulp cell differentiation by activation of adenylate-activated protein kinase by dimethyldiphosphate. Clinical indexes, such as the probing depth, attachment loss level and probing bleeding index, were significantly improved in patients with periodontitis treated with metformin, which may play a role in the prevention and treatment of periodontal disease by promoting the proliferation, migration and osteogenic differentiation of periodontal ligament stem cells. Metformin has been proven to inhibit the growth and proliferation of tumor cells and plays an important role in the prevention and treatment of oral tumors such as oral squamous cell carcinoma. At present, research remains in the in vitro and animal experimental stage, and the related mechanism needs to be further explored. Clinical trials remain in the evaluation of clinical indicators, so large-scale, long-term, multicenter, randomized controlled clinical trials need to be further developed
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Objective @#To study the regulatory effect of coiled-coil domain containing 134 (CCDC134) on the osteogenic differentiation of human dental pulp stem cells (hDPSCs).@*Methods @# HDPSCs were isolated and cultured from dental pulp tissue and transfected with NC-CCDC134, shCCDC134 and CCDC134 lentiviruses. They were divided into the control group, negative control group, CCDC134 downregulation (shCCDC134) group and CCDC134 overexpression (CCDC134) group. Surface markers of hDPSCs (Stro-1, CD105, CD34, CD45) were detected by flow cytometry; colony formation was analyzed by toluidine blue staining; ALP expression was estimated by ALP staining; mineralized nodule formation was evaluated by alizarin red staining; lipid droplet formation was examined by oil red staining; and gene and protein expression of CCDC134, Runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), bone morphogenetic protein-2 (BMP-2), and mothers against decapentaplegic homolog 1 (SMAD1) was detected by qPCR and western blot, respectively. Further, a BMP-2 activator (BMP-2) and inhibitor (Dorsomorphin) were used to down-regulate and up-regulate CCDC134, respectively (shCCDC134, shCCDC134+BMP-2, CCDC134, CCDC134+Dorsomorphin), in hDPSCs. The hDPSC aggregates were subcutaneously transplanted into nude mice for 2 months, and new bone formation was detected by H&E staining. The BMP-2/SMAD1 signaling in each group was detected by qPCR.@*Results@#hDPSCs showed high expression of mesenchymal markers and low expression of hematopoietic markers. Compared with the control group, the expression of CCDC134 was increased in the osteogenic-induced hDPSCs (P < 0.05). Compared with the negative control group, the expression of CCDC134 was decreased in the shCCDC134 group, whereas it was increased in the CCDC134 group (P < 0.05). The mineralized nodules, osteogenic genes and proteins in the shCCDC134 group were decreased (P < 0.05), while they were increased in the CCDC134 group (P < 0.05). The expression of BMP-2/SMAD1 signaling decreased in the shCCDC134 group, while it increased in the CCDC134 group (P < 0.05). Compared to the shCCDC134 group, osteogenic genes and proteins increased in the shCCDC134+BMP-2 group, and subcutaneous new bone formation increased in nude mice (P < 0.05). The indexes of the CCDC134+Dorsomorphin group decreased compared with the CCDC134 group (P < 0.05).@*Conclusion@#CCDC134 promotes the osteogenic differentiation of hDPSCs by regulating the BMP-2/SMAD1 signaling pathway.
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Mesenchymal stem cells (MSCs) are a kind of stem cells with self-renewal ability and multidirectional differentiation potential. At present, as the main cell source for bone tissue engineering, MSCs can be used to treat various skeletal disorders. DNA methylation is an important epigenetic mechanism involving the occurrence and development of osteoporosis, osteonecrosis and other trauma-related skeletal disorders by regulating expression of osteogenic-specific genes in osteogenic differentiation of MSCs. The authors review the research progress in regulation of skeletal disorders by DNA methylation regulating osteogenic differentiation of MSCs by overviewing DNA methylation, mechanisms of DNA methylation regulating osteogenic differentiation of MSCs involving trauma-related bone disease and related treatment measures so as to provide references for the research and treatment of trauma-related skeletal disorders.
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Objective@#To compare the efficiency and biocompatibility of four different silanes on immobilizing c(RGDfK) peptide on titanium surface.@*Methods @# After alkali-heat treatment (group OH), the titanium surface was treated with 3-aminopropyltriethoxysilane (APTES) (group OHAP), 3-chloropropyltriethoxysilane (CPTES) (group OHCP) (3-mercaptopropyltrimethoxysilane (MPTS) (group OHMPT) and 3-isobutyryloxy propyltrimethoxysilane(γ- MPS) (group OHMPS) to immobilize the c(RGDfK) cyclic peptide and constructa titanium-silane-c(RGDfK) coating. The NT group was the blank control group. The surface morphology and wettability of the coatings were detected using scanning electron microscopy and contact angle measurement. The elemental composition of the titanium surface was analyzed using X-ray photoelectron spectroscopy. After fluorescent staining with 4’,6-diamino-2-phenylindole (DAPI) and phalloidin, the adhesion of mouse preosteoblast MC3T3-E1 cells on the surface of the materials was observed using laser confocal microscopy. Cell counting kit-8 (CCK-8) and alkaline phosphatase (ALP) activity assays were used to evaluate the proliferation and osteogenic differentiation of MC3T3-E1 cells on the surface of the materials, respectively. @*Results @#Scanning electron microscope observation showed a spongy-like 3-dimensional network formed on the titanium surface after alkali-heat treatment with silane-c(RGDfK) coating adhesion. The wettability of each group was greatly improved compared to the untreated titanium surface. The element ratios of Si/Ti and amide-N/Ti in the OHMPS group were the highest. The OHAP group exhibited the best cell adhesion effect. The cell proliferation and ALP activity of the OHAP, OHMPT, and OHMPS groups were significantly higher than the control group (P <0.05); there was no statistical difference between the OHCP group and the control group.@*Conclusion @#MPTS, CPTES and γ-MPS covalently immobilized cyclic peptide c(RGDfK) on the titanium surface, which promoted adhesion, proliferation and osteogenic differentiation of MC3T3-E1 cells. Theγ-MPS conjugated C (RGDfK)cyclic peptide exhibited the best effect. MPTS, CPTES and γ-MPS coupled with c(RGDfK) cyclic peptides had similar biological properties.
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Objective@# To investigate the effects of over expression and low expression of antisense transcripts of circular RNA cerebellar degeneration associated protein 1 (CDR1as) in Balb/C mouse bone marrow mesenchymal stem cells (BMSCs) on factors related to osteogenesis and angiogenesis.@*Methods@#BMSCs were cultured and identified in vitro. The lentiviral (LV) vector containing the overexpressed and silenced circRNA CDR1as genes and the control lentivirus were respectively transfected into mouse BMSCs, and stable cell lines were screened. The cells were divided into the circRNACDR1as over expression group and the over expression control group, and the CircRNACDR1as low expression group and the low expression control group. The components were stained with Alizarin Red S and alkaline phosphatase after 14 and 21 days of osteoinduction; qRT-PCR was used to detect the target genes circRNA CDR1as, osteogenic differentiation markers alkaline phosphatase (ALP), runt- related transcription factor 2 (RUNX2), osteocalcin (OCN), osteopontin (OPN), osterix(Osx), collagen I (COL-1), and the mRNA expression levels of vascular endothelial grown factor (VEGF) and angiogenin-1 (Ang-1). @*Results@# The results of alizarin red staining and alkaline phosphatase staining showed that the extracellular matrix calcium precipitation and ALP staining area of the over expression experimental group was greater than its control group, and those of the low expression experimental group was less than its control group. As the number of days of osteogenic induction increased, the calcium precipitation and ALP staining in each group also increased. RT-PCR results showed that the mRNA expression levels of circRNA CDR1as, ALP, RUNX2, OCN, OPN, OSX, COL-1, VEGF and Ang-1 in the over expression experimental group BMSCs were significantly increased (P<0.001). In the low expression experimental group, the mRNA expression levels of circRNA CDR1as, ALP, RUNX2, OCN, OPN, OSX, COL-1, VEGF and Ang-1 in BMSCs were significantly reduced (P<0.001). @*Conclusion@# Over expression of the circRNA CDR1as gene promotes the osteogenic differentiation and angiogenesis of BMSCs. Low expression of the circRNA CDR1as gene inhibits the osteogenic differentiation and angiogenesis of BMSCs.
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Objective @#To investigate the effect of silencing histone deacetylase 9 (HDAC9) expression on the proliferation and osteogenic differentiation of periodontal ligament stem cells (PDLSCs).@*Methods@# PDLSCs were isolated, cultured and identified in vitro. An siRNA construct specific for HDAC9 was transfected into PDLSCs (siHDAC9 group), and a nontargeting siRNA was used as a control (siNC group). The interference effect was determined by qRT-PCR. The cell cycle progression of PDLSCs was detected using flow cytometry. The proliferation activity of PDLSCs was detected via CCK-8 assay. Western blotting was used to detect the protein expression of proliferating cell nuclear antigen (PCNA). The mRNA expression of runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP) was investigated by qRT-PCR. The protein expression of RUNX2 was detected by western blotting. In addition, the formation of mineralized nodules was assessed by alizarin red staining. @*Results@#Compared with that in the siNC group, the mRNA expression of HDAC9 in the siHDAC9 group was lower (P < 0.01). Moreover, compared with those in the siNC group, the proliferation index (P<0.01), proliferation activity (P<0.05) and protein expression of PCNA (P<0.01) in the siHDAC9 group were all increased. Compared with the siNC group, the siHDAC9 group exhibited higher mRNA expression of RUNX2 and ALP (P < 0.05), and the protein expression of RUNX2 showed the same results (P < 0.01). The results of alizarin red staining showed that compared to the siNC group, the siHDAC9 group formed more mineralized nodules.@* Conclusion@#Silencing HDAC9 expression can promote the proliferation and osteogenic differentiation of PDLSCs.
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Objective:To investigate the effects of fluoride exposure on proliferation, apoptosis and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in mice.Methods:BMSCs were isolated and cultured from femur bone marrow of C57BL/6 mice (6 - 8 weeks). The cells in passage 3 were used to detect the surface markers of stem cells by flow cytometry. The cells were cultured in media with a final fluoride concentration of 0.0, 0.1, 1.0, 5.0, 10.0, 15.0, 20.0 and 40.0 mg/L, respectively. The effects of different fluoride concentrations on BMSCs cell proliferation (CCK8 method), apoptosis (flow cytometry analysis), osteogenic differentiation ability [alizarin red and alkaline phosphatase (ALP) staining] were detected. Western blot was applied to detect the levels of apoptosis-related proteins [poly ADP-ribose polymerase (PARP)], mitogen-activated protein kinase (MAPK) pathway member proteins [extracellular regulated protein kinase 1/2 (ERK1/2), c-Jun amino-terminal kinase (JNK), p38 and phosphorylated ERK, JNK, p38 (p-ERK, p-JNK, p-p38)], osteogenic differentiation-related protein [Runt-related transcription factor 2 (Runx2), ALP] and Wnt/β-catenin pathway member proteins [glycogen synthase kinase-3β (GSK3β), phosphorylated GSK3β (p-GSK3β) and β-catenin]. Immunocytofluorescense staining was applied to evaluate the expression levels of p-GSK3β and β-catenin. The two pathways (MAPK and Wnt/β-catenin) were blocked by SP600125 and DKK-1, respectively, to testify their involvement in mechanisms of apoptosis and osteogenic differentiation.Results:The mouse BMSCs were successfully isolated and cultured. Flow cytometry analysis showed that the mesenchymal stem cell surface biomarkers (CD73, CD90 and CD105) were positively expressed. The comparison of cell proliferation at three time points (24, 48 and 72 h) in each concentration group was statistically significant ( F = 65.36, 160.04 and 365.32, P < 0.001), and the comparison of early apoptosis (24 h) in each concentration group was statistically significant ( F = 214.04, P < 0.001); compared with the 0.0 mg/L group, the cell proliferation in 15.0, 20.0 and 40.0 mg/L groups decreased, and the early apoptosis rate in 10.0, 15.0 and 20.0 mg/L groups increased ( P < 0.05). When cells were treated with 15.0 mg/L fluoride for 0 - 24 h, the p-JNK/JNK ratio was higher at 2, 4, 8, 12, 18 and 24 h compared with that at 0 min ( P < 0.05); compared with the fluoride group (15.0 mg/L), the early apoptosis rate of cells after SP600125 block decreased ( P < 0.05), and the protein expression levels of PARP and p-JNK decreased ( P < 0.05). After osteogenic induction, compared with the 0.0 mg/L group, in 0.1 and 1.0 mg/L groups ALP staining was enhanced and the number of calcified nodules increased, and the protein expression levels of Runx2 and ALP in the 0.1 and 1.0 mg/L groups were higher ( P < 0.05). After osteogenic induction, compared with the 0.0 mg/L group, the p-GSK3β/GSK3β ratio and β-catenin protein level were significantly higher in the 0.1 and 1.0 mg/L groups ( P < 0.05); and compared with the fluoride group (1.0 mg/L), addition of DKK-1 significantly decreased the protein expression levels of p-GSK3β and β-catenin and reduced the nuclear entry of β-catenin, and ALP staining decreased and the number of calcified nodules decreased. Conclusions:High concentration of fluoride (> 10.0 mg/L) inhibits the proliferation and promotes apoptosis of BMSCs, while low concentration of fluoride (0.1, 1.0 mg/L) promotes osteogenic differentiation. The MAPK/JNK pathway and the classical Wnt pathway are involved in the above cellular processes, respectively.