Osteoporosis represents a prevalent and debilitating comorbidity in patients diagnosed with type 2 diabetes mellitus(T2DM),which is characterized by suppressed osteoblast function and disrupted bone microarchitecture....Osteoporosis represents a prevalent and debilitating comorbidity in patients diagnosed with type 2 diabetes mellitus(T2DM),which is characterized by suppressed osteoblast function and disrupted bone microarchitecture.In this study,we utilized male C57BL/6 J mice to investigate the role of SIRT3 in T2DM.Decreased SIRT3 expression and impaired mitochondrial quality control mechanism are observed in both in vitro and in vivo models of T2DM.Mechanistically,SIRT3 suppression results in hyperacetylation of FOXO3,hindering the activation of the PINK1/PRKN mediated mitophagy pathway and resulting in accumulation of dysfunctional mitochondria.Genetical overexpression or pharmacological activation of SIRT3 restores deacetylation status of FOXO3,thus facilitating mitophagy and ameliorating osteogenic impairment in T2DM.Collectively,our findings highlight the fundamental regulatory function of SIRT3 in mitochondrial quality control,crucial for maintaining bone homeostasis in T2DM.These insights not only enhance our understanding of the molecular mechanisms underlying diabetic osteoporosis but also identify SIRT3 as a promising therapeutic target for diabetic osteoporosis.展开更多
Osteogenic ability impairment and myelosuppression are common complications of chemotherapy and many chemotherapeutics can affect the skeletal system.Skeletal system protection is necessary for cancer chemotherapy.In ...Osteogenic ability impairment and myelosuppression are common complications of chemotherapy and many chemotherapeutics can affect the skeletal system.Skeletal system protection is necessary for cancer chemotherapy.In this study,osteogenic growth peptide(OGP)and tetrahedral framework nucleic-acid nanostructures(tFNAs)are combined to form a peptide-DNA complex OGP-tFNAs,which aims to combine the positive biological effect on tissue protection and regeneration.The bone marrow protection and bone formation effect of OGP-tFNAs are investigated in chemotherapy-induced myelosuppressive mice.The results show that OGP-tFNAs could reduce the cell damage degree from 5-fluorouracil(5-FU)in vitro and maintained the osteogenic differentiation potential.Furthermore,OGP-tFNAs accelerate bone defect regeneration in myelosuppressive mice.In conclusion,OGP-tFNAs could protect the osteogenic differentiation potential of bone marrow stromal cells(BMSCs)from 5-FU injury and maintain the bone formation ability of myelosuppressive mice suffering from chemotherapy.展开更多
Osteogenesis is driven by the differentiation of osteoblasts and the mineralization of the bone matrix,with oral-derived stem cells playing a significant role in this process.Various post-translational modifications(P...Osteogenesis is driven by the differentiation of osteoblasts and the mineralization of the bone matrix,with oral-derived stem cells playing a significant role in this process.Various post-translational modifications(PTMs),such as phosphorylation,acetylation,methylation,and glycosylation,regulate osteogenic differentiation(OD).These modifications influence the expression of osteogenic genes by modulating the activity of key transcription factors like runt-related transcription factor 2 and osterix.While the molecular mechanisms behind OD are increasingly understood,many questions remain,particularly regarding how PTMs control the specificity and efficiency of stem cell differentiation.Recent research into these modifications has underscored the potential of stem cell therapy for bone regeneration and treating bone-related diseases.This review summarizes the role of PTMs in the OD of oral-derived stem cells,discusses their clinical applications,and suggests future research directions.展开更多
NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxi...NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxidation property and corrosion resistance of the NiTi alloy.In order to overcome the above problems,we constructed Zn/polydopamine(PDA)/Chitosan-Catechol(CS-C)composite coating on the surface of NiTi alloy in this paper.The surface morphology and wettability of the coating were characterized by scanning electron microscopy(SEM)and optical contact angle measuring instrument,respectively.The results showed that the Zn/CS-C coating was successfully prepared,and exhibited good hydrophilic property,especially the sample Zn/PDA/CS-C-24 h.In addition,the corrosion resistance,antioxidation property and biological properties of the coating were systematically analyzed.The results indicated that the Zn/PDA/CS-C composite coating exhibited good corrosion resistance and antibacterial property,antioxidant property and osteogenic activity,especially sample Zn/PDA/CS-C-24 h.The sample Zn/PDA/CS-C-24 h could effectively protect osteoblasts from reactive oxygen species(ROS)damage and promote cell proliferation and osteoblast differentiation.This study provides a feasible and effective strategy for the surface modification of orthopedic implant.展开更多
BACKGROUND Fracture is one of the most pervasive injuries in the musculoskeletal system,and there is a complex interaction between macrophages and adipose tissue-derived stem cells(ADSCs)in fracture healing.However,tw...BACKGROUND Fracture is one of the most pervasive injuries in the musculoskeletal system,and there is a complex interaction between macrophages and adipose tissue-derived stem cells(ADSCs)in fracture healing.However,two-dimensional(2D)coculture of macrophages and ADSCs can not accurately mimic the in vivo cell microenvironment.AIM To establish both 2D and 3D osteogenic coculture models to investigate the interaction between macrophages and ADSCs.METHODS After obtaining ADSCs from surgery and inducing differentiation of the THP1 cell line,we established 2D and 3D osteogenic coculture models.To assess the level of osteogenic differentiation,we used alizarin red staining and measured the relative expression levels of osteogenic differentiation markers osteocalcin,Runt-related transcription factor 2,and alkaline phosphatase through polymerase chain reaction.Verification was conducted by analyzing the expression changes of N-cadherin and the activation of the Wnt/β-catenin signaling pathway using western blotting.RESULTS In this study,it was discovered that macrophages in 3D culture inhibited osteogenic differentiation of ADSCs,contrary to the effect in 2D culture.This observation confirmed the significance of intricate intercellular connections in the 3D culture environment.Additionally,the 3D culture group exhibited significantly higher N-cadherin expression and showed reducedβ-catenin and Wnt1 protein levels compared to the 2D culture group.CONCLUSION Macrophages promoted ADSC osteogenic differentiation in 2D culture conditions but inhibited it in 3D culture.The 3D culture environment might inhibit the Wnt/β-catenin signaling pathway by upregulating N-cadherin expression,ultimately hindering the osteogenic differentiation of ADSCs.By investigating the process of osteogenesis in ADSCs,this study provides novel ideas for exploring 3D osteogenesis in ADSCs,fracture repair,and other bone trauma repair.展开更多
Zinc(Zn)-based materials show broad application prospects for bone repair due to their biodegradability and good biocompatibility.In particular,Zn metal foam has unique interconnected pore structure that facilitates i...Zinc(Zn)-based materials show broad application prospects for bone repair due to their biodegradability and good biocompatibility.In particular,Zn metal foam has unique interconnected pore structure that facilitates inward growth of new bone tissue,making it ideal candidates for orthopedic implants.However,pure Zn metal foam shows poor mechanical property,high degradation rate,and unsatisfactory osteogenic activity.Herein,Zinc-manganese(Zn-Mn)alloy foams were electrodeposited in Zn and Mn-containing electrolytes to overcome the concerns.The results showed that Mn could be incorporated into the foams in the form of MnZn_(13).Zn-Mn alloy foams showed better mechanical property and osteogenic activity as well as moderate degradation rate when compared with pure Zn metal foam.In addition,these properties could also be regulated by preparation process.The peak stress and osteogenic activity increased with deposition current(0.3‒0.5 A)and electrolyte pH(3‒5),but decreased with electrolyte temperature(20‒40℃),while the degradation rate exhibited opposite tendency,which suggests high deposition current and electrolyte pH and low electrolyte temperature can fabricate Zn-Mn alloy foam with favorable mechanical property,moderate degradation rate,and osteogenic activity.These findings provide a valuable reference for the design and fabrication of novel Zn-based biodegradable materials.展开更多
Objective This study aimed to investigate the effect of Astragalus(AST)on osteoporosis(OP)and the downstream mechanisms.Methods Human bone marrow-derived mesenchymal stem cells(hBMSCs)were induced to differentiate int...Objective This study aimed to investigate the effect of Astragalus(AST)on osteoporosis(OP)and the downstream mechanisms.Methods Human bone marrow-derived mesenchymal stem cells(hBMSCs)were induced to differentiate into osteogenic cells.After transfection with relevant plasmids,cell proliferation,cell cycle progression,and apoptosis were assessed.Alizarin red staining was used to detect calcium nodules in the cells,alkaline phosphatase(ALP)staining was used to detect ALP activity in the cells,and quantitative reverse transcription-polymerase chain reaction and western blotting were used to determine RUNX2 and Osterix expression levels.An OP rat model was established using ovariectomy and micro-computed tomography scanning.Hematoxylin and eosin staining and Masson’s trichrome staining were used to evaluate the pathological conditions of bone tissues,while immunohistochemistry was conducted to detect RUNX2 in bone tissues.Results AST promoted the osteogenic differentiation of BMSCs,reduced miR-181d-5p expression levels,and increased SOX11 expression levels.Restoring miR-181d-5p expression or reducing SOX11 expression levels reversed the effects of AST on the osteogenic differentiation of hBMSCs.miR-181d-5p was found to target SOX11 in hBMSCs.AST improved OP in rats,and miR-181d-5p overexpression or SOX11 inhibition reversed the therapeutic effects of AST on OP in rats.Conclusion AST promoted the osteogenic differentiation of hBMSCs and alleviated OP by targeting SOX11 via miR-181d-5p.展开更多
BACKGROUND Periodontitis is an inflammatory disease caused by the host’s immune response and various interactions between pathogens,which lead to the loss of connective tissue and bone.In recent years,mesenchymal ste...BACKGROUND Periodontitis is an inflammatory disease caused by the host’s immune response and various interactions between pathogens,which lead to the loss of connective tissue and bone.In recent years,mesenchymal stem cell(SC)transplantation technology has become a research hotspot,which can form periodontal ligament,cementum,and alveolar bone through proliferation and differentiation.AIM To elucidate the regulatory effects of WD repeat-containing protein 36(WDR36)on the senescence,migration,and osteogenic differentiation of periodontal ligament SCs(PDLSCs).METHODS The migration and chemotaxis of PDLSCs were detected by the scratch-wound migration test and transwell chemotaxis test.Alkaline phosphatase(ALP)activity,Alizarin red staining,calcium content,and real-time reverse transcription polymerase chain reaction(RT-qPCR)of key transcription factors were used to detect the osteogenic differentiation function of PDLSCs.Cell senescence was determined by senescence-associatedβ-galactosidase staining.RESULTS The 24-hour and 48-hour scratch-wound migration test and 48-hour transwell chemotaxis test showed that overexpression of WDR36 inhibited the migration/chemotaxis of PDLSCs.Simultaneously,WDR36 depletion promoted the migration/chemotaxis of PDLSCs.The results of ALP activity,Alizarin red staining,calcium content,and RTqPCR showed that overexpression of WDR36 inhibited the osteogenic differentiation of PDLSCs,and WDR36 depletion promoted the osteogenic differentiation of PDLSCs.Senescence-associatedβ-galactosidase staining showed that 0.1μg/mL icariin(ICA)and overexpression of WDR36 inhibited the senescence of PDLSCs,and WDR36 depletion promoted the osteogenic differentiation of PDLSCs.CONCLUSION WDR36 inhibits the migration and chemotaxis,osteogenic differentiation,and senescence of PDLSCs;0.1μg/mL ICA inhibits the senescence of PDLSCs.Therefore,WDR36 might serve as a target for periodontal tissue regeneration and the treatment of periodontitis.展开更多
BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical chal...BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical challenge.Enhancer of zeste homolog 2(EZH2),a histone H3 lysine 27 methyltransferase,regulates osteogenesis through epigenetic mechanisms,but its role in SCAPs remains unclear.We hypothesized that EZH2 modulates SCAP osteogenic differentiation via interaction with lysine demethylase 2B(KDM2B),offering a target for therapeutic intervention.AIM To investigate the functional role and molecular mechanism of EZH2 in SCAP osteogenic differentiation.METHODS SCAPs were isolated from healthy human third molars(n=6 donors).Osteogenic differentiation was assessed via Alizarin red staining and alkaline phosphatase assays.EZH2 overexpression/knockdown models were established using lentiviral vectors.Protein interactions were analyzed by co-immunoprecipitation,transcriptomic changes via microarray(Affymetrix platform),and chromatin binding by chromatin immunoprecipitation-quantitative polymerase chain reaction.In vivo bone formation was evaluated in immunodeficient mice(n=8/group)transplanted with SCAPs-hydroxyapatite scaffolds.Data were analyzed using Student’s t-test and ANOVA.RESULTS EZH2 overexpression increased osteogenic markers and mineralized nodule formation.In vivo,EZH2-overexpressing SCAPs generated 10%more bone/dentin-like tissue.Co-immunoprecipitation confirmed EZH2-KDM2B interaction,and peptide-mediated disruption of this binding enhanced osteogenesis.Transcriptome analysis identified 1648 differentially expressed genes(971 upregulated;677 downregulated),with pathway enrichment in Wnt/β-catenin signaling.CONCLUSION EZH2 promotes SCAP osteogenesis via antagonistic interaction with KDM2B,and targeted disruption of this axis offers a translatable strategy for bone regeneration.展开更多
The bone marrow microenvironment is critical for the maintenance and functionality of stem/progenitor cells,which are essential for bone development and regeneration.However,the composition and potential use of bone m...The bone marrow microenvironment is critical for the maintenance and functionality of stem/progenitor cells,which are essential for bone development and regeneration.However,the composition and potential use of bone marrow interstitial fluid have not been well explored.In this study,we report the role of neonatal bovine bone marrow interstitial fluid(NBIF)in enhancing the bone regeneration capacity of human bone marrow mesenchymal stem cells(hBMSCs).Unlike adult bovine bone marrow interstitial fluid(ABIF),NBIF-fed hBMSCs exhibit enhanced self-renewal and osteogenic potential and bone marrow homing ability,along with transcriptome changes as compared to hBMSCs cultured in standard fetal bovine serum(FBS)supplemented medium.Mass spectrometry analysis reveals that multiple secreted factors associated with tissue repair and bone development are enriched in NBIF compared to FBS and ABIF.The combined use of NBIF-enriched Nerve Growth Factor(NGF),Lactoferrin(LTF),and High Mobility Group Protein B1(HMGB1),together with Insulin-Like Growth Factor 1(IGF1)for culturing hBMSCs in the presence of FBS can enhance osteogenic potential and bone marrow homing ability,mimicking NBIF's effects.These findings highlight the role of interstitial fluid in the bone marrow microenvironment and its potential to optimize stem cell-based therapies.展开更多
For bone regenerative engineering,it is a promising method to form skeletal tissues differentiating from human bone morrow mesenchyme stem cells(hBMSCs).However,it is still a critical challenge to efficiently control ...For bone regenerative engineering,it is a promising method to form skeletal tissues differentiating from human bone morrow mesenchyme stem cells(hBMSCs).However,it is still a critical challenge to efficiently control ostogenesis and clearly reveal the influence factor.To this end,the fluorescent gold nanodots(Au NDs) with highly negative charges as osteogenic induction reagent are successfully synthesized,which display better than commercial osteogenic induction medium through the investigations of ALP activity(2.5 folds) and cytoskeleton staining(1.5 folds).Two kinds of oligopeptides with different bio-structures(cysteine,Cys and glutathione,GSH) are selected for providing surficial charges on Au NDs.It is revealed that Au-Cys with more negative charges(-51 mV) play better role than Au-GSH(-19 mV) in osteogenic differentiation,when both of them have same size(~2 nm),sphere shape and show similar cell uptake amount.To explore deeply,osteogenesis related signaling pathways are monitored,revealing that the enhancement of osteogenic differentiation was through autophagy signaling pathway triggered by Au-Cys.And the promotion of highly negative charges in osteogenic diffe rentiation was further proved via sliver nanodots(Ag NDs,Ag-Cys and Ag-GSH) and carbon nanodots(CDs,Cys-CDs and GSH-CDs).This work indicates part of insights during hBMSCs differentiation and provides a novel strategy in osteogenic differentiation process.展开更多
Objective:Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focusing on combining gene transfection with tissue engineering techniques.The aim of this study is to ...Objective:Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focusing on combining gene transfection with tissue engineering techniques.The aim of this study is to investigate the effect of connective tissue growth factor(CTGF) on the proliferation and osteogenic differentiation of the bone marrow mesenchymal stem cells(MSCs).Methods:A CTGF-expressing plasmid(pCTGF) was constructed and transfected into MSCs.Then expressions of bone morphogenesis-related genes,proliferation rate,alkaline phosphatase activity,and mineralization were examined to evaluate the osteogenic potential of the CTGF gene-modified MSCs.Results:Overexpression of CTGF was confirmed in pCTGF-MSCs.pCTGF transfection significantly enhanced the proliferation rates of pCTGF-MSCs(P<0.05).CTGF induced a 7.5-fold increase in cell migration over control(P<0.05).pCTGF transfection enhanced the expression of bone matrix proteins,such as bone sialo-protein,osteocalcin,and collagen type I in MSCs.The levels of alkaline phosphatase(ALP) activities of pCTGF-MSCs at the 1st and 2nd weeks were 4.0-and 3.0-fold higher than those of MSCs cultured in OS-medium,significantly higher than those of mock-MSCs and normal control MSCs(P<0.05).Overexpression of CTGF in MSCs enhanced the capability to form mineralized nodules.Conclusion:Overexpression of CTGF could improve the osteogenic differentiation ability of MSCs,and the CTGF gene-modified MSCs are potential as novel cell resources of bone tissue engineering.展开更多
Periodontal diseases are infectious diseases that are characterized by progressive damage to dental support tissue.The major goal of periodontal therapy is to regenerate the periodontium destroyed by periodontal disea...Periodontal diseases are infectious diseases that are characterized by progressive damage to dental support tissue.The major goal of periodontal therapy is to regenerate the periodontium destroyed by periodontal diseases.Human periodontal ligament(PDL)tissue possesses periodontal regenerative properties,and periodontal ligament stem cells(PDLSCs)with the capacity for osteogenic differentiation show strong potential in clinical application for periodontium repair and regeneration.Noncoding RNAs(ncRNAs),which include a substantial portion of poly-A tail mature RNAs,are considered“transcriptional noise.”Recent studies show that ncRNAs play a major role in PDLSC differentiation;therefore,exploring how ncRNAs participate in the osteogenic differentiation of PDLSCs may help to elucidate the underlying mechanism of the osteogenic differentiation of PDLSCs and further shed light on the potential of stem cell transplantation for periodontium regeneration.In this review paper,we discuss the history of PDLSC research and highlight the regulatory mechanism of ncRNAs in the osteogenic differentiation of PDLSCs.展开更多
BACKGROUND In the clinical scenario,adult patients with periodontal diseases and dental malformation,characterized by dental crowding in lower anterior teeth with the thin biotype,often require orthodontic treatment.T...BACKGROUND In the clinical scenario,adult patients with periodontal diseases and dental malformation,characterized by dental crowding in lower anterior teeth with the thin biotype,often require orthodontic treatment.This case report aimed to evaluate the clinical and radiographic outcomes of periodontally accelerated osteogenic orthodontics(PAOO)combined with autologous platelet-rich fibrin(PRF)in an adult patient with class I malocclusion along with dental crowding,a thin periodontal biotype,and buccal plate deficiency.CASE SUMMARY A 32-year-old female complaining of dental crowding and gingival bleeding was referred to the orthodontic clinic.The patient underwent periodontal risk assessment prior to orthodontic treatment.She was diagnosed with a high risk of gingival recession due to dental crowding,root prominence,loss of buccal plates,and a thin gingival tissue biotype.The treatment regimen included PAOO combined with autologous PRF for alveolar augmentation and interproximal enamel reduction for moderate dental crowding.Clinically,PAOO-assisted orthodontic tooth movement in this case showed enhanced periodontium remodeling.Radiographic outcomes also showed statistically significant improvements(P<0.01)in the mandibular buccal alveolar bone.CONCLUSION This case report suggests the combination of autologous PRF with PAOO to enhance bone augmentation and long-term tissue support in adult orthodontic patients with periodontal disease.展开更多
The rapid degradation of magnesium(Mg)-based implants in physiological environment limits its clinical applications, and alloying treatment is an effective way to regulate the degradation rate of Mg-based materials. I...The rapid degradation of magnesium(Mg)-based implants in physiological environment limits its clinical applications, and alloying treatment is an effective way to regulate the degradation rate of Mg-based materials. In the present study, three Mg alloys, including Mg-0.8Ca(denoted as ZQ), Mg-0.8Ca-5Zn-1.5Ag(denoted as ZQ71) and Mg-0.8Ca-5Zn-2.5Ag(denoted as ZQ63), were fabricated by alloying with calcium(Ca), zinc(Zn) and silver(Ag). The results obtained from electrochemical corrosion tests and in vitro degradation evaluation demonstrated that the three Mg alloys exhibited distinct corrosion resistance, and ZQ71 exhibited the lowest degradation rate in vitro among them. After addition of Zn and Ag, the antibacterial potential of Mg alloys was also enhanced. The in vitro cell experiments showed that all the three Mg alloys had good biocompatibility. After implantation in a rat femoral defect, ZQ71 showed significantly higher osteogenic activity and bone substitution rate than ZQ63 and ZQ, due to its higher corrosion resistance as well as the stimulatory effects of the released metallic ions. In addition, the average daily degradation rate of each Mg alloy in vivo was significantly higher than that in vitro, as could be due to the implantation site located in the highly vascularized trabecular region. Importantly, the correlations between the in vitro and in vivo degradation parameters of the Mg alloys were systematically analyzed to find out the potential predictors of the in vivo degradation performance of the materials. The current work not only evaluated the clinical potential of the three biodegradable Mg alloys as bone grafts but also provided a feasible approach for predicting the in vivo degradation behavior of biodegradable materials.展开更多
Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulatio...Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·Lpargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis.展开更多
ALKBH1 was recently discovered as a demethylase for DNA N6-methyladenine （N6-mA）, a new epigenetic modification, and interacts with the core transcriptional pluripotency network of embryonic stem cells. However, the...ALKBH1 was recently discovered as a demethylase for DNA N6-methyladenine （N6-mA）, a new epigenetic modification, and interacts with the core transcriptional pluripotency network of embryonic stem cells. However, the role of ALKBH1 and DNA N6-mA in regulating osteogenic differentiation is largely unknown. In this study, we demonstrated that the expression of ALKBH1 in human mesenchymal stem cells （MSCs） was upregulated during osteogenic induction. Knockdown of ALKBH1 increased the genomic DNA N6-mA levels and significantly reduced the expression of osteogenic-related genes, alkaline phosphatase activity, and mineralization. ALKBHl-depleted MSCs also exhibited a restricted capacity for bone formation in vivo. By contrast, the ectopic overexpression of ALKBH1 enhanced osteoblastic differentiation. Mechanically, we found that the depletion of ALKBH1 resulted in the accumulation of N6-mA on the promoter region of ATF4, which subsequently silenced ATF4 transcription. In addition, restoring the expression of ATP by adenovirus-mediated transduction successfully rescued osteogenic differentiation. Taken together, our results demonstrate that ALKBH1 is indispensable for the osteogenic differentiation of MSCs and indicate that DNA N6-mA modifications area new mechanism for the epigenetic regulation of stem cell differentiation.展开更多
AFF1 and AFF4 belong to the AFF （AF4/FMR2） family of proteins, which function as scaffolding proteins linking two different transcription elongation factors, positive elongation factor b （P-TEFb） and ELL1/2, in su...AFF1 and AFF4 belong to the AFF （AF4/FMR2） family of proteins, which function as scaffolding proteins linking two different transcription elongation factors, positive elongation factor b （P-TEFb） and ELL1/2, in super elongation complexes （SECs）. Both AFF1 and AFF4 regulate gene transcription through elongation and chromatln remodeling. However, their function in the osteogenic differentiation of mesenchymal stem cells （MSCs） is unknown. In this study, we show that small interfering RNA （siRNA）-mediated depletion of AFF1 in human MSCs leads to increased alkaline phosphatase （ALP） activity, enhanced mineralization and upregulated expression of osteogenic-related genes. On the contrary, depletion of AFF4 significantly inhibits the osteogenic potential of MSCs. In addition, we confirm that overexpression of AFF1 and AFF4 differentially affects osteogenic differentiation in vitro and MSC-mediated bone formation in vivo. Mechanistically, we find that AFFI regulates the expression of DKK1 via binding to its promoter region. Depletion of DKK1 in HA-AFFl-overexpressing MSCs abrogates the impairment of osteogenic differentiation. Moreover, we detect that AFF4 is enriched in the promoter region of ID1. AFF4 knockdown blunts the BRE luciferase activity, SP7 expression and ALP activity induced by BMP2 treatment. In conclusion, our data indicate that AFF1 and AFF4 differentially regulate the osteogenic differentiation of human MSCs.AFF1 and AFF4 belong to the AFF （AF4/FMR2） family of proteins, which function as scaffolding proteins linking two different transcription elongation factors, positive elongation factor b （P-TEFb） and ELL1/2, in super elongation complexes （SECs）. Both AFFI and AFF4 regulate gene transcription through elongation and chromatln remodeling. However, their function in the osteogenic differentiation of mesenchymal stem cells （MSCs） is unknown. In this study, we show that small interfering RNA （siRNA）-mediated depletion of AFF1 in human MSCs leads to increased alkaline phosphatase （ALP） activity, enhanced mineralization and upregulated expression of osteogenic-related genes. On the contrary, depletion of AFF4 significantly inhibits the osteogenic potential of MSCs. In addition, we confirm that overexpression of AFF1 and AFF4 differentially affects osteogenic differentiation in vitro and MSC-mediated bone formation in vivo. Mechanistically, we find that AFFI regulates the expression of DKK1 via binding to its promoter region. Depletion of DKK1 in HA-AFFl-overexpressing MSCs abrogates the impairment of osteogenic differentiation. Moreover, we detect that AFF4 is enriched in the promoter region of ID1. AFF4 knockdown blunts the BRE luciferase activity, SP7 expression and ALP activity induced by BMP2 treatment. In conclusion, our data indicate that AFF1 and AFF4 differentially regulate the osteogenic differentiation of human MSCs.展开更多
Infection is one of the major causes of failure of orthopedic implants. Our previous study demonstrated that nanotube modification of the implant surface, together with nanotubes loaded with quaternized chitosan （hyd...Infection is one of the major causes of failure of orthopedic implants. Our previous study demonstrated that nanotube modification of the implant surface, together with nanotubes loaded with quaternized chitosan （hydroxypropyltrimethyl ammonium chloride chitosan, HACC）, could effectively inhibit bacterial adherence and biofilm formation in vitro. Therefore, the aim of this study was to further investigate the in vitro cytocompatibility with osteogenic cells and the in vivo anti-infection activity of titanium implants with HACC-loaded nanotubes （NT-H）. The titanium implant （Ti）, nanotubes without polymer loading （NT）, and nanotubes loaded with chitosan （NT-C） were fabricated and served as controls. Firstly, we evaluated the cytocompatibility of these specimens with human bone marrow-derived mesenchymal stem cells in vitro. The observation of cell attachment, proliferation, spreading, and viability in vitro showed that NT-H has improved osteogenic activity compared with Ti and NT-C. A prophylaxis rat model with implantation in the femoral medullary cavity and inoculation with methiciUin-resistant Staphylococcus aureus was established and evaluated by radiographical, microbiological, and histopathological assessments. Our in vivo study demonstrated that NT-H coatings exhibited significant anti-infection capability compared with the Ti and NT-C groups. In conclusion, HACC-loaded nanotubes fabricated on a titanium substrate show good compatibility with osteogenic cells and enhanced anti-infection ability in vivo, providing a good foundation for clinical application to combat orthopedic implant-associated infections.展开更多
Bacteria-associated infection and poor osseointegration are two main reasons for orthopedic implant failure.Ti-Cu alloy exhibited excellent antibacterial property,but still presented unsatisfied osteogenic activities....Bacteria-associated infection and poor osseointegration are two main reasons for orthopedic implant failure.Ti-Cu alloy exhibited excellent antibacterial property,but still presented unsatisfied osteogenic activities.Therefore,Ti-Cu alloy was surface modified by an alkali-heat treatment in this paper to improve the osteogenic ability without reduction in antibacterial ability.A TiO_(2)/CuO/Cu_(2)O composite coating with nanostructure was deposited on Ti-Cu alloy.The coating showed increased roughness and great hydrophilicity.Antibacterial tests indicated that the modified Ti-Cu alloy exhibited stronger antibacterial ability against Staphylococcus aureus(S.aureus)than Ti-Cu alloy.Meanwhile,cell experiments demonstrated that the composite coating promoted initial adhesion and spreading of MC3T3-E1 cells,enhanced alkaline phosphatase(ALP)activities as well as extracellular matrix(ECM)mineralization,and significantly upregulated osteogenesis-related gene expressions.It was suggested that the nano-structured TiO_(2)/CuO/Cu_(2)O coating on Ti-Cu alloy might provide a potential strategy for orthopedic implant failure.展开更多
基金supported by the National Key Research and Development Project (2021YFA1201404)National Natural Science Foundation of China Major Project (81991514)+6 种基金General Project (82272530, 82372459)Jiangsu Province Medical Innovation Center of Orthopedic Surgery (CXZX202214)Jiangsu Provincial Key Medical Center FoundationJiangsu Provincial Medical Outstanding Talent FoundationJiangsu Provincial Medical Youth Talent FoundationJiangsu Provincial Key Medical Talent Foundationthe Fundamental Research Funds for the Central Universities (14380493, 14380494)
文摘Osteoporosis represents a prevalent and debilitating comorbidity in patients diagnosed with type 2 diabetes mellitus(T2DM),which is characterized by suppressed osteoblast function and disrupted bone microarchitecture.In this study,we utilized male C57BL/6 J mice to investigate the role of SIRT3 in T2DM.Decreased SIRT3 expression and impaired mitochondrial quality control mechanism are observed in both in vitro and in vivo models of T2DM.Mechanistically,SIRT3 suppression results in hyperacetylation of FOXO3,hindering the activation of the PINK1/PRKN mediated mitophagy pathway and resulting in accumulation of dysfunctional mitochondria.Genetical overexpression or pharmacological activation of SIRT3 restores deacetylation status of FOXO3,thus facilitating mitophagy and ameliorating osteogenic impairment in T2DM.Collectively,our findings highlight the fundamental regulatory function of SIRT3 in mitochondrial quality control,crucial for maintaining bone homeostasis in T2DM.These insights not only enhance our understanding of the molecular mechanisms underlying diabetic osteoporosis but also identify SIRT3 as a promising therapeutic target for diabetic osteoporosis.
基金supported by National Natural Science Foundation of China(Nos.82322015,82171006)Sichuan Province Youth Science and Technology Innovation Team(No.2022JDTD0021)+3 种基金Sichuan Science and Technology Program(No.2022NSFSC0002)West China Hospital of Stomatology Sichuan University(No.RCDWJS2024-3)Sichuan Science and Technology Program(Nos.2023NSFSC1706,2024NSFSC1589)Postdoctoral Science Foundation of China(No.BX20220220)。
文摘Osteogenic ability impairment and myelosuppression are common complications of chemotherapy and many chemotherapeutics can affect the skeletal system.Skeletal system protection is necessary for cancer chemotherapy.In this study,osteogenic growth peptide(OGP)and tetrahedral framework nucleic-acid nanostructures(tFNAs)are combined to form a peptide-DNA complex OGP-tFNAs,which aims to combine the positive biological effect on tissue protection and regeneration.The bone marrow protection and bone formation effect of OGP-tFNAs are investigated in chemotherapy-induced myelosuppressive mice.The results show that OGP-tFNAs could reduce the cell damage degree from 5-fluorouracil(5-FU)in vitro and maintained the osteogenic differentiation potential.Furthermore,OGP-tFNAs accelerate bone defect regeneration in myelosuppressive mice.In conclusion,OGP-tFNAs could protect the osteogenic differentiation potential of bone marrow stromal cells(BMSCs)from 5-FU injury and maintain the bone formation ability of myelosuppressive mice suffering from chemotherapy.
文摘Osteogenesis is driven by the differentiation of osteoblasts and the mineralization of the bone matrix,with oral-derived stem cells playing a significant role in this process.Various post-translational modifications(PTMs),such as phosphorylation,acetylation,methylation,and glycosylation,regulate osteogenic differentiation(OD).These modifications influence the expression of osteogenic genes by modulating the activity of key transcription factors like runt-related transcription factor 2 and osterix.While the molecular mechanisms behind OD are increasingly understood,many questions remain,particularly regarding how PTMs control the specificity and efficiency of stem cell differentiation.Recent research into these modifications has underscored the potential of stem cell therapy for bone regeneration and treating bone-related diseases.This review summarizes the role of PTMs in the OD of oral-derived stem cells,discusses their clinical applications,and suggests future research directions.
基金jointly supported by the Natural Science Foundation of Shanxi Province(Nos.202203021222127,202403021212109).
文摘NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxidation property and corrosion resistance of the NiTi alloy.In order to overcome the above problems,we constructed Zn/polydopamine(PDA)/Chitosan-Catechol(CS-C)composite coating on the surface of NiTi alloy in this paper.The surface morphology and wettability of the coating were characterized by scanning electron microscopy(SEM)and optical contact angle measuring instrument,respectively.The results showed that the Zn/CS-C coating was successfully prepared,and exhibited good hydrophilic property,especially the sample Zn/PDA/CS-C-24 h.In addition,the corrosion resistance,antioxidation property and biological properties of the coating were systematically analyzed.The results indicated that the Zn/PDA/CS-C composite coating exhibited good corrosion resistance and antibacterial property,antioxidant property and osteogenic activity,especially sample Zn/PDA/CS-C-24 h.The sample Zn/PDA/CS-C-24 h could effectively protect osteoblasts from reactive oxygen species(ROS)damage and promote cell proliferation and osteoblast differentiation.This study provides a feasible and effective strategy for the surface modification of orthopedic implant.
文摘BACKGROUND Fracture is one of the most pervasive injuries in the musculoskeletal system,and there is a complex interaction between macrophages and adipose tissue-derived stem cells(ADSCs)in fracture healing.However,two-dimensional(2D)coculture of macrophages and ADSCs can not accurately mimic the in vivo cell microenvironment.AIM To establish both 2D and 3D osteogenic coculture models to investigate the interaction between macrophages and ADSCs.METHODS After obtaining ADSCs from surgery and inducing differentiation of the THP1 cell line,we established 2D and 3D osteogenic coculture models.To assess the level of osteogenic differentiation,we used alizarin red staining and measured the relative expression levels of osteogenic differentiation markers osteocalcin,Runt-related transcription factor 2,and alkaline phosphatase through polymerase chain reaction.Verification was conducted by analyzing the expression changes of N-cadherin and the activation of the Wnt/β-catenin signaling pathway using western blotting.RESULTS In this study,it was discovered that macrophages in 3D culture inhibited osteogenic differentiation of ADSCs,contrary to the effect in 2D culture.This observation confirmed the significance of intricate intercellular connections in the 3D culture environment.Additionally,the 3D culture group exhibited significantly higher N-cadherin expression and showed reducedβ-catenin and Wnt1 protein levels compared to the 2D culture group.CONCLUSION Macrophages promoted ADSC osteogenic differentiation in 2D culture conditions but inhibited it in 3D culture.The 3D culture environment might inhibit the Wnt/β-catenin signaling pathway by upregulating N-cadherin expression,ultimately hindering the osteogenic differentiation of ADSCs.By investigating the process of osteogenesis in ADSCs,this study provides novel ideas for exploring 3D osteogenesis in ADSCs,fracture repair,and other bone trauma repair.
基金supported by the Key Research and Development Program of Shanxi Province(202102130501007)the Natural Science Foundation of Shanxi Province(202403021212109,202203021211173)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2024L039).
文摘Zinc(Zn)-based materials show broad application prospects for bone repair due to their biodegradability and good biocompatibility.In particular,Zn metal foam has unique interconnected pore structure that facilitates inward growth of new bone tissue,making it ideal candidates for orthopedic implants.However,pure Zn metal foam shows poor mechanical property,high degradation rate,and unsatisfactory osteogenic activity.Herein,Zinc-manganese(Zn-Mn)alloy foams were electrodeposited in Zn and Mn-containing electrolytes to overcome the concerns.The results showed that Mn could be incorporated into the foams in the form of MnZn_(13).Zn-Mn alloy foams showed better mechanical property and osteogenic activity as well as moderate degradation rate when compared with pure Zn metal foam.In addition,these properties could also be regulated by preparation process.The peak stress and osteogenic activity increased with deposition current(0.3‒0.5 A)and electrolyte pH(3‒5),but decreased with electrolyte temperature(20‒40℃),while the degradation rate exhibited opposite tendency,which suggests high deposition current and electrolyte pH and low electrolyte temperature can fabricate Zn-Mn alloy foam with favorable mechanical property,moderate degradation rate,and osteogenic activity.These findings provide a valuable reference for the design and fabrication of novel Zn-based biodegradable materials.
基金supported by the National Natural Science Foundation of China(No.81700888).
文摘Objective This study aimed to investigate the effect of Astragalus(AST)on osteoporosis(OP)and the downstream mechanisms.Methods Human bone marrow-derived mesenchymal stem cells(hBMSCs)were induced to differentiate into osteogenic cells.After transfection with relevant plasmids,cell proliferation,cell cycle progression,and apoptosis were assessed.Alizarin red staining was used to detect calcium nodules in the cells,alkaline phosphatase(ALP)staining was used to detect ALP activity in the cells,and quantitative reverse transcription-polymerase chain reaction and western blotting were used to determine RUNX2 and Osterix expression levels.An OP rat model was established using ovariectomy and micro-computed tomography scanning.Hematoxylin and eosin staining and Masson’s trichrome staining were used to evaluate the pathological conditions of bone tissues,while immunohistochemistry was conducted to detect RUNX2 in bone tissues.Results AST promoted the osteogenic differentiation of BMSCs,reduced miR-181d-5p expression levels,and increased SOX11 expression levels.Restoring miR-181d-5p expression or reducing SOX11 expression levels reversed the effects of AST on the osteogenic differentiation of hBMSCs.miR-181d-5p was found to target SOX11 in hBMSCs.AST improved OP in rats,and miR-181d-5p overexpression or SOX11 inhibition reversed the therapeutic effects of AST on OP in rats.Conclusion AST promoted the osteogenic differentiation of hBMSCs and alleviated OP by targeting SOX11 via miR-181d-5p.
文摘BACKGROUND Periodontitis is an inflammatory disease caused by the host’s immune response and various interactions between pathogens,which lead to the loss of connective tissue and bone.In recent years,mesenchymal stem cell(SC)transplantation technology has become a research hotspot,which can form periodontal ligament,cementum,and alveolar bone through proliferation and differentiation.AIM To elucidate the regulatory effects of WD repeat-containing protein 36(WDR36)on the senescence,migration,and osteogenic differentiation of periodontal ligament SCs(PDLSCs).METHODS The migration and chemotaxis of PDLSCs were detected by the scratch-wound migration test and transwell chemotaxis test.Alkaline phosphatase(ALP)activity,Alizarin red staining,calcium content,and real-time reverse transcription polymerase chain reaction(RT-qPCR)of key transcription factors were used to detect the osteogenic differentiation function of PDLSCs.Cell senescence was determined by senescence-associatedβ-galactosidase staining.RESULTS The 24-hour and 48-hour scratch-wound migration test and 48-hour transwell chemotaxis test showed that overexpression of WDR36 inhibited the migration/chemotaxis of PDLSCs.Simultaneously,WDR36 depletion promoted the migration/chemotaxis of PDLSCs.The results of ALP activity,Alizarin red staining,calcium content,and RTqPCR showed that overexpression of WDR36 inhibited the osteogenic differentiation of PDLSCs,and WDR36 depletion promoted the osteogenic differentiation of PDLSCs.Senescence-associatedβ-galactosidase staining showed that 0.1μg/mL icariin(ICA)and overexpression of WDR36 inhibited the senescence of PDLSCs,and WDR36 depletion promoted the osteogenic differentiation of PDLSCs.CONCLUSION WDR36 inhibits the migration and chemotaxis,osteogenic differentiation,and senescence of PDLSCs;0.1μg/mL ICA inhibits the senescence of PDLSCs.Therefore,WDR36 might serve as a target for periodontal tissue regeneration and the treatment of periodontitis.
基金Supported by National Key Research and Development Program,No.2022YFA1104401Beijing Natural Science Foundation,No.7222075+1 种基金CAMS Innovation Fund for Medical Sciences,No.2019RU020Innovation Research Team Project of Beijing Stomatological Hospital,No.CXTD202204.
文摘BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical challenge.Enhancer of zeste homolog 2(EZH2),a histone H3 lysine 27 methyltransferase,regulates osteogenesis through epigenetic mechanisms,but its role in SCAPs remains unclear.We hypothesized that EZH2 modulates SCAP osteogenic differentiation via interaction with lysine demethylase 2B(KDM2B),offering a target for therapeutic intervention.AIM To investigate the functional role and molecular mechanism of EZH2 in SCAP osteogenic differentiation.METHODS SCAPs were isolated from healthy human third molars(n=6 donors).Osteogenic differentiation was assessed via Alizarin red staining and alkaline phosphatase assays.EZH2 overexpression/knockdown models were established using lentiviral vectors.Protein interactions were analyzed by co-immunoprecipitation,transcriptomic changes via microarray(Affymetrix platform),and chromatin binding by chromatin immunoprecipitation-quantitative polymerase chain reaction.In vivo bone formation was evaluated in immunodeficient mice(n=8/group)transplanted with SCAPs-hydroxyapatite scaffolds.Data were analyzed using Student’s t-test and ANOVA.RESULTS EZH2 overexpression increased osteogenic markers and mineralized nodule formation.In vivo,EZH2-overexpressing SCAPs generated 10%more bone/dentin-like tissue.Co-immunoprecipitation confirmed EZH2-KDM2B interaction,and peptide-mediated disruption of this binding enhanced osteogenesis.Transcriptome analysis identified 1648 differentially expressed genes(971 upregulated;677 downregulated),with pathway enrichment in Wnt/β-catenin signaling.CONCLUSION EZH2 promotes SCAP osteogenesis via antagonistic interaction with KDM2B,and targeted disruption of this axis offers a translatable strategy for bone regeneration.
基金financially supported by the Guangzhou National Laboratory(grant#GZNL2025C02022,A.M.#QNPG2317,J.Z.)partially by the National Natural Science Foundation of China(31988101)。
文摘The bone marrow microenvironment is critical for the maintenance and functionality of stem/progenitor cells,which are essential for bone development and regeneration.However,the composition and potential use of bone marrow interstitial fluid have not been well explored.In this study,we report the role of neonatal bovine bone marrow interstitial fluid(NBIF)in enhancing the bone regeneration capacity of human bone marrow mesenchymal stem cells(hBMSCs).Unlike adult bovine bone marrow interstitial fluid(ABIF),NBIF-fed hBMSCs exhibit enhanced self-renewal and osteogenic potential and bone marrow homing ability,along with transcriptome changes as compared to hBMSCs cultured in standard fetal bovine serum(FBS)supplemented medium.Mass spectrometry analysis reveals that multiple secreted factors associated with tissue repair and bone development are enriched in NBIF compared to FBS and ABIF.The combined use of NBIF-enriched Nerve Growth Factor(NGF),Lactoferrin(LTF),and High Mobility Group Protein B1(HMGB1),together with Insulin-Like Growth Factor 1(IGF1)for culturing hBMSCs in the presence of FBS can enhance osteogenic potential and bone marrow homing ability,mimicking NBIF's effects.These findings highlight the role of interstitial fluid in the bone marrow microenvironment and its potential to optimize stem cell-based therapies.
基金supported by the National Nature Science Foundation of China(Nos.51861145311,22005338)Science Foundation of China University of Petroleum,Beijing(No.2462017YJRC027)Open Project of State Key Laboratory of Superhard Materials(Jilin University 201802)。
文摘For bone regenerative engineering,it is a promising method to form skeletal tissues differentiating from human bone morrow mesenchyme stem cells(hBMSCs).However,it is still a critical challenge to efficiently control ostogenesis and clearly reveal the influence factor.To this end,the fluorescent gold nanodots(Au NDs) with highly negative charges as osteogenic induction reagent are successfully synthesized,which display better than commercial osteogenic induction medium through the investigations of ALP activity(2.5 folds) and cytoskeleton staining(1.5 folds).Two kinds of oligopeptides with different bio-structures(cysteine,Cys and glutathione,GSH) are selected for providing surficial charges on Au NDs.It is revealed that Au-Cys with more negative charges(-51 mV) play better role than Au-GSH(-19 mV) in osteogenic differentiation,when both of them have same size(~2 nm),sphere shape and show similar cell uptake amount.To explore deeply,osteogenesis related signaling pathways are monitored,revealing that the enhancement of osteogenic differentiation was through autophagy signaling pathway triggered by Au-Cys.And the promotion of highly negative charges in osteogenic diffe rentiation was further proved via sliver nanodots(Ag NDs,Ag-Cys and Ag-GSH) and carbon nanodots(CDs,Cys-CDs and GSH-CDs).This work indicates part of insights during hBMSCs differentiation and provides a novel strategy in osteogenic differentiation process.
基金supported by the National Basic Research Program (973) of China(No.2005CB623900)
文摘Objective:Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focusing on combining gene transfection with tissue engineering techniques.The aim of this study is to investigate the effect of connective tissue growth factor(CTGF) on the proliferation and osteogenic differentiation of the bone marrow mesenchymal stem cells(MSCs).Methods:A CTGF-expressing plasmid(pCTGF) was constructed and transfected into MSCs.Then expressions of bone morphogenesis-related genes,proliferation rate,alkaline phosphatase activity,and mineralization were examined to evaluate the osteogenic potential of the CTGF gene-modified MSCs.Results:Overexpression of CTGF was confirmed in pCTGF-MSCs.pCTGF transfection significantly enhanced the proliferation rates of pCTGF-MSCs(P<0.05).CTGF induced a 7.5-fold increase in cell migration over control(P<0.05).pCTGF transfection enhanced the expression of bone matrix proteins,such as bone sialo-protein,osteocalcin,and collagen type I in MSCs.The levels of alkaline phosphatase(ALP) activities of pCTGF-MSCs at the 1st and 2nd weeks were 4.0-and 3.0-fold higher than those of MSCs cultured in OS-medium,significantly higher than those of mock-MSCs and normal control MSCs(P<0.05).Overexpression of CTGF in MSCs enhanced the capability to form mineralized nodules.Conclusion:Overexpression of CTGF could improve the osteogenic differentiation ability of MSCs,and the CTGF gene-modified MSCs are potential as novel cell resources of bone tissue engineering.
基金Supported by National Natural Science Foundation of ChinaNo.81600882 and 81870755+4 种基金China Postdoctoral Science FoundationNo. 2019M663009President Foundation of Nanfang HospitalSouthern Medical UniversityNo.2019B002.
文摘Periodontal diseases are infectious diseases that are characterized by progressive damage to dental support tissue.The major goal of periodontal therapy is to regenerate the periodontium destroyed by periodontal diseases.Human periodontal ligament(PDL)tissue possesses periodontal regenerative properties,and periodontal ligament stem cells(PDLSCs)with the capacity for osteogenic differentiation show strong potential in clinical application for periodontium repair and regeneration.Noncoding RNAs(ncRNAs),which include a substantial portion of poly-A tail mature RNAs,are considered“transcriptional noise.”Recent studies show that ncRNAs play a major role in PDLSC differentiation;therefore,exploring how ncRNAs participate in the osteogenic differentiation of PDLSCs may help to elucidate the underlying mechanism of the osteogenic differentiation of PDLSCs and further shed light on the potential of stem cell transplantation for periodontium regeneration.In this review paper,we discuss the history of PDLSC research and highlight the regulatory mechanism of ncRNAs in the osteogenic differentiation of PDLSCs.
基金Supported by Natured Science Foundation of Anhui Province,No.1908085MH255.
文摘BACKGROUND In the clinical scenario,adult patients with periodontal diseases and dental malformation,characterized by dental crowding in lower anterior teeth with the thin biotype,often require orthodontic treatment.This case report aimed to evaluate the clinical and radiographic outcomes of periodontally accelerated osteogenic orthodontics(PAOO)combined with autologous platelet-rich fibrin(PRF)in an adult patient with class I malocclusion along with dental crowding,a thin periodontal biotype,and buccal plate deficiency.CASE SUMMARY A 32-year-old female complaining of dental crowding and gingival bleeding was referred to the orthodontic clinic.The patient underwent periodontal risk assessment prior to orthodontic treatment.She was diagnosed with a high risk of gingival recession due to dental crowding,root prominence,loss of buccal plates,and a thin gingival tissue biotype.The treatment regimen included PAOO combined with autologous PRF for alveolar augmentation and interproximal enamel reduction for moderate dental crowding.Clinically,PAOO-assisted orthodontic tooth movement in this case showed enhanced periodontium remodeling.Radiographic outcomes also showed statistically significant improvements(P<0.01)in the mandibular buccal alveolar bone.CONCLUSION This case report suggests the combination of autologous PRF with PAOO to enhance bone augmentation and long-term tissue support in adult orthodontic patients with periodontal disease.
基金financially supported by InterGovernmental S&T Cooperation Project Between China and Romania (2018LMNY003)Sichuan Science and Technology Innovation Team of China (2019JDTD0008)the Fundamental Research Funds for the Central Universities (2021SCU12071)。
文摘The rapid degradation of magnesium(Mg)-based implants in physiological environment limits its clinical applications, and alloying treatment is an effective way to regulate the degradation rate of Mg-based materials. In the present study, three Mg alloys, including Mg-0.8Ca(denoted as ZQ), Mg-0.8Ca-5Zn-1.5Ag(denoted as ZQ71) and Mg-0.8Ca-5Zn-2.5Ag(denoted as ZQ63), were fabricated by alloying with calcium(Ca), zinc(Zn) and silver(Ag). The results obtained from electrochemical corrosion tests and in vitro degradation evaluation demonstrated that the three Mg alloys exhibited distinct corrosion resistance, and ZQ71 exhibited the lowest degradation rate in vitro among them. After addition of Zn and Ag, the antibacterial potential of Mg alloys was also enhanced. The in vitro cell experiments showed that all the three Mg alloys had good biocompatibility. After implantation in a rat femoral defect, ZQ71 showed significantly higher osteogenic activity and bone substitution rate than ZQ63 and ZQ, due to its higher corrosion resistance as well as the stimulatory effects of the released metallic ions. In addition, the average daily degradation rate of each Mg alloy in vivo was significantly higher than that in vitro, as could be due to the implantation site located in the highly vascularized trabecular region. Importantly, the correlations between the in vitro and in vivo degradation parameters of the Mg alloys were systematically analyzed to find out the potential predictors of the in vivo degradation performance of the materials. The current work not only evaluated the clinical potential of the three biodegradable Mg alloys as bone grafts but also provided a feasible approach for predicting the in vivo degradation behavior of biodegradable materials.
基金supported by grants from the National Natural Science Foundation of China(81200763 to WG and 81070809 to YZ)the Program for New Century Excellent Talents(NCET)at the University from Ministry of Education of China(NCET-11-0026)+1 种基金the PKU School of Stomatology for Talented Young Investigators(PKUSS20150107)the Construction Program for the National Key Clinical Specialty from the National Health and Family Planning Commission of China(2011)
文摘Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·Lpargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis.
基金supported by grants from the National Natural Science Foundation of China (No.81271178 and 81470777)
文摘ALKBH1 was recently discovered as a demethylase for DNA N6-methyladenine （N6-mA）, a new epigenetic modification, and interacts with the core transcriptional pluripotency network of embryonic stem cells. However, the role of ALKBH1 and DNA N6-mA in regulating osteogenic differentiation is largely unknown. In this study, we demonstrated that the expression of ALKBH1 in human mesenchymal stem cells （MSCs） was upregulated during osteogenic induction. Knockdown of ALKBH1 increased the genomic DNA N6-mA levels and significantly reduced the expression of osteogenic-related genes, alkaline phosphatase activity, and mineralization. ALKBHl-depleted MSCs also exhibited a restricted capacity for bone formation in vivo. By contrast, the ectopic overexpression of ALKBH1 enhanced osteoblastic differentiation. Mechanically, we found that the depletion of ALKBH1 resulted in the accumulation of N6-mA on the promoter region of ATF4, which subsequently silenced ATF4 transcription. In addition, restoring the expression of ATP by adenovirus-mediated transduction successfully rescued osteogenic differentiation. Taken together, our results demonstrate that ALKBH1 is indispensable for the osteogenic differentiation of MSCs and indicate that DNA N6-mA modifications area new mechanism for the epigenetic regulation of stem cell differentiation.
基金supported by grants from the National Natural Science Foundation of China(NSFC,81722014,81571001,81500354,and 81621062)Sichuan Province Science and Technology Innovation Team Program(2017TD0016)State Key Laboratory of Oral Diseases(SKLOD201704)
文摘AFF1 and AFF4 belong to the AFF （AF4/FMR2） family of proteins, which function as scaffolding proteins linking two different transcription elongation factors, positive elongation factor b （P-TEFb） and ELL1/2, in super elongation complexes （SECs）. Both AFF1 and AFF4 regulate gene transcription through elongation and chromatln remodeling. However, their function in the osteogenic differentiation of mesenchymal stem cells （MSCs） is unknown. In this study, we show that small interfering RNA （siRNA）-mediated depletion of AFF1 in human MSCs leads to increased alkaline phosphatase （ALP） activity, enhanced mineralization and upregulated expression of osteogenic-related genes. On the contrary, depletion of AFF4 significantly inhibits the osteogenic potential of MSCs. In addition, we confirm that overexpression of AFF1 and AFF4 differentially affects osteogenic differentiation in vitro and MSC-mediated bone formation in vivo. Mechanistically, we find that AFFI regulates the expression of DKK1 via binding to its promoter region. Depletion of DKK1 in HA-AFFl-overexpressing MSCs abrogates the impairment of osteogenic differentiation. Moreover, we detect that AFF4 is enriched in the promoter region of ID1. AFF4 knockdown blunts the BRE luciferase activity, SP7 expression and ALP activity induced by BMP2 treatment. In conclusion, our data indicate that AFF1 and AFF4 differentially regulate the osteogenic differentiation of human MSCs.AFF1 and AFF4 belong to the AFF （AF4/FMR2） family of proteins, which function as scaffolding proteins linking two different transcription elongation factors, positive elongation factor b （P-TEFb） and ELL1/2, in super elongation complexes （SECs）. Both AFFI and AFF4 regulate gene transcription through elongation and chromatln remodeling. However, their function in the osteogenic differentiation of mesenchymal stem cells （MSCs） is unknown. In this study, we show that small interfering RNA （siRNA）-mediated depletion of AFF1 in human MSCs leads to increased alkaline phosphatase （ALP） activity, enhanced mineralization and upregulated expression of osteogenic-related genes. On the contrary, depletion of AFF4 significantly inhibits the osteogenic potential of MSCs. In addition, we confirm that overexpression of AFF1 and AFF4 differentially affects osteogenic differentiation in vitro and MSC-mediated bone formation in vivo. Mechanistically, we find that AFFI regulates the expression of DKK1 via binding to its promoter region. Depletion of DKK1 in HA-AFFl-overexpressing MSCs abrogates the impairment of osteogenic differentiation. Moreover, we detect that AFF4 is enriched in the promoter region of ID1. AFF4 knockdown blunts the BRE luciferase activity, SP7 expression and ALP activity induced by BMP2 treatment. In conclusion, our data indicate that AFF1 and AFF4 differentially regulate the osteogenic differentiation of human MSCs.
基金financially supported by the National Natural Science Foundation of China (No.31271015,81501856)National Key R&D Program (2016YFC1102100)+1 种基金Shanghai Science and Technology Development Fund (13JC1403900,13DZ2294000)Medical Engineering Collaborative Project of Shanghai Jiao Tong University (YG2014ZD01)
文摘Infection is one of the major causes of failure of orthopedic implants. Our previous study demonstrated that nanotube modification of the implant surface, together with nanotubes loaded with quaternized chitosan （hydroxypropyltrimethyl ammonium chloride chitosan, HACC）, could effectively inhibit bacterial adherence and biofilm formation in vitro. Therefore, the aim of this study was to further investigate the in vitro cytocompatibility with osteogenic cells and the in vivo anti-infection activity of titanium implants with HACC-loaded nanotubes （NT-H）. The titanium implant （Ti）, nanotubes without polymer loading （NT）, and nanotubes loaded with chitosan （NT-C） were fabricated and served as controls. Firstly, we evaluated the cytocompatibility of these specimens with human bone marrow-derived mesenchymal stem cells in vitro. The observation of cell attachment, proliferation, spreading, and viability in vitro showed that NT-H has improved osteogenic activity compared with Ti and NT-C. A prophylaxis rat model with implantation in the femoral medullary cavity and inoculation with methiciUin-resistant Staphylococcus aureus was established and evaluated by radiographical, microbiological, and histopathological assessments. Our in vivo study demonstrated that NT-H coatings exhibited significant anti-infection capability compared with the Ti and NT-C groups. In conclusion, HACC-loaded nanotubes fabricated on a titanium substrate show good compatibility with osteogenic cells and enhanced anti-infection ability in vivo, providing a good foundation for clinical application to combat orthopedic implant-associated infections.
基金financial support from the National Natural Science Foundation of China(No.31971253)。
文摘Bacteria-associated infection and poor osseointegration are two main reasons for orthopedic implant failure.Ti-Cu alloy exhibited excellent antibacterial property,but still presented unsatisfied osteogenic activities.Therefore,Ti-Cu alloy was surface modified by an alkali-heat treatment in this paper to improve the osteogenic ability without reduction in antibacterial ability.A TiO_(2)/CuO/Cu_(2)O composite coating with nanostructure was deposited on Ti-Cu alloy.The coating showed increased roughness and great hydrophilicity.Antibacterial tests indicated that the modified Ti-Cu alloy exhibited stronger antibacterial ability against Staphylococcus aureus(S.aureus)than Ti-Cu alloy.Meanwhile,cell experiments demonstrated that the composite coating promoted initial adhesion and spreading of MC3T3-E1 cells,enhanced alkaline phosphatase(ALP)activities as well as extracellular matrix(ECM)mineralization,and significantly upregulated osteogenesis-related gene expressions.It was suggested that the nano-structured TiO_(2)/CuO/Cu_(2)O coating on Ti-Cu alloy might provide a potential strategy for orthopedic implant failure.
