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1.
J Cell Mol Med ; 25(5): 2666-2678, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33605035

RESUMO

Teeth arise from the tooth germ through sequential and reciprocal interactions between immature epithelium and mesenchyme during development. However, the detailed mechanism underlying tooth development from tooth germ mesenchymal cells (TGMCs) remains to be fully understood. Here, we investigate the role of Wnt/ß-catenin signalling in BMP9-induced osteogenic/odontogenic differentiation of TGMCs. We first established the reversibly immortalized TGMCs (iTGMCs) derived from young mouse mandibular molar tooth germs using a retroviral vector expressing SV40 T antigen flanked with the FRT sites. We demonstrated that BMP9 effectively induced expression of osteogenic markers alkaline phosphatase, collagen A1 and osteocalcin in iTGMCs, as well as in vitro matrix mineralization, which could be remarkably blunted by knocking down ß-catenin expression. In vivo implantation assay revealed that while BMP9-stimulated iTGMCs induced robust formation of ectopic bone, knocking down ß-catenin expression in iTGMCs remarkably diminished BMP9-initiated osteogenic/odontogenic differentiation potential of these cells. Taken together, these discoveries strongly demonstrate that reversibly immortalized iTGMCs retained osteogenic/odontogenic ability upon BMP9 stimulation, but this process required the participation of canonical Wnt signalling both in vitro and in vivo. Therefore, BMP9 has a potential to be applied as an efficacious bio-factor in osteo/odontogenic regeneration and tooth engineering. Furthermore, the iTGMCs may serve as an important resource for translational studies in tooth tissue engineering.


Assuntos
Fator 2 de Diferenciação de Crescimento/genética , Células-Tronco Mesenquimais/metabolismo , Odontogênese/genética , Osteogênese/genética , Germe de Dente/citologia , Via de Sinalização Wnt , Animais , Diferenciação Celular , Linhagem Celular , Transformação Celular Neoplásica , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Fator 2 de Diferenciação de Crescimento/metabolismo , Xenoenxertos , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos
2.
J Mater Chem B ; 12(25): 6005-6032, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38869470

RESUMO

Periodontitis is an immune-inflammatory disease caused by dental plaque, and deteriorates the periodontal ligament, causes alveolar bone loss, and may lead to tooth loss. To treat periodontitis, antibacterial and anti-inflammation approaches are required to reduce bone loss. Thus, appropriate drug administration methods are significant. Due to their "syringeability", biocompatibility, and convenience, injectable hydrogels and associated methods have been extensively studied and used for periodontitis therapy. Such hydrogels are made from natural and synthetic polymer materials using physical and/or chemical cross-linking approaches. Interestingly, some injectable hydrogels are stimuli-responsive hydrogels, which respond to the local microenvironment and form hydrogels that release drugs. Therefore, as injectable hydrogels are different and highly varied, we systematically reviewed the periodontal treatment field from three perspectives: raw material sources, cross-linking methods, and stimuli-responsive methods. We then discussed current challenges and opportunities for the translation of hydrogels to clinic, which may guide further injectable hydrogel designs for periodontitis.


Assuntos
Hidrogéis , Periodontite , Periodontite/tratamento farmacológico , Hidrogéis/química , Humanos , Animais , Injeções , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
3.
Pediatr Discov ; 1(3)2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38371743

RESUMO

The microorganisms in the human body gradually change and maintain a dynamic balance with the development of physiology and pathology. Oral microbiota is one of the most important microbiota in human body. It is not only closely related to the occurrence and development of oral diseases, but also plays an important role in the overall health. In childhood, the population of oral microorganisms is relatively small, but with the growth of age and tooth development, the species and quantity of oral microorganisms are gradually increasing. Different oral diseases also have their corresponding main microorganisms, and these dominant microorganisms change at different stages of the disease. In this review, we summarized and compared the main pathogenic microorganisms of several common oral diseases in children and adults. In addition, the possible association and difference between adults and children of the main pathogenic microorganisms in different stages of the same or different diseases are also discussed in order to provide research data for the development and diagnosis of common oral diseases in children and adults.

4.
Front Cell Dev Biol ; 11: 1158936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283947

RESUMO

Stem cells from the apical papilla (SCAPs) are promising candidates for regenerative endodontic treatment and tissue regeneration in general. However, harvesting enough cells from the limited apical papilla tissue is difficult, and the cells lose their primary phenotype over many passages. To get over these challenges, we immortalized human SCAPs with lentiviruses overexpressing human telomerase reverse transcriptase (hTERT). Human immortalized SCAPs (hiSCAPs) exhibited long-term proliferative activity without tumorigenic potential. Cells also expressed mesenchymal and progenitor biomarkers and exhibited multiple differentiation potentials. Interestingly, hiSCAPs gained a stronger potential for osteogenic differentiation than the primary cells. To further investigate whether hiSCAPs could become prospective seed cells in bone tissue engineering, in vitro and in vivo studies were performed, and the results indicated that hiSCAPs exhibited strong osteogenic differentiation ability after infection with recombinant adenoviruses expressing BMP9 (AdBMP9). In addition, we revealed that BMP9 could upregulate ALK1 and BMPRII, leading to an increase in phosphorylated Smad1 to induce the osteogenic differentiation of hiSCAPs. These results support the application of hiSCAPs in tissue engineering/regeneration schemes as a stable stem cell source for osteogenic differentiation and biomineralization, which could be further used in stem cell-based clinical therapies.

5.
J Biomed Biotechnol ; 2012: 601549, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226941

RESUMO

Critical-size osseous defects cannot heal without surgical intervention and can pose a significant challenge to craniofacial reconstruction. Autologous bone grafting is the gold standard for repair but is limited by a donor site morbidity and a potentially inadequate supply of autologous bone. Alternatives to autologous bone grafting include the use of alloplastic and allogenic materials, mesenchymal stem cells, and bone morphogenetic proteins. Bone morphogenetic proteins (BMPs) are essential mediators of bone formation involved in the regulation of differentiation of osteoprogenitor cells into osteoblasts. Here we focus on the use of BMPs in experimental models of craniofacial surgery and clinical applications of BMPs in the reconstruction of the cranial vault, palate, and mandible and suggest a model for the use of BMPs in personalized stem cell therapies.


Assuntos
Proteínas Morfogenéticas Ósseas/uso terapêutico , Ensaios Clínicos como Assunto/tendências , Face/cirurgia , Medicina de Precisão/tendências , Crânio/cirurgia , Transplante de Células-Tronco/tendências , Animais , Humanos
6.
Front Bioeng Biotechnol ; 10: 1036061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324890

RESUMO

Apical periodontitis is a common clinical disease caused by bacteria; bacterial metabolites can cause an imbalance in bone homeostasis, bone mass reduction, and tooth loss. Bone resorption in apical periodontitis causes a concentration of stress in the tooth and periodontal tissues during occlusion, which aggravates the disease. Emerging evidence indicates that bone morphogenetic protein 9 (BMP9), also known as growth differentiation factor 2(Gdf2), may play an important role in tooth and dentoalveolar development. Herein, we investigated the role of BMP9 in the development of apical periodontitis and its effects on the biomechanics of dentoalveolar bone. Apical periodontitis models were established in five BMP9 knockout (KO) mice and five C57BL/6 WT (wild-type) mice. At baseline and 14, 28, and 42 days after modeling, in vivo micro-computed tomography analysis and three-dimensional (3D) reconstruction were performed to evaluate the apical lesion in each mouse, and confirm that the animal models were successfully established. Finite element analysis (FEA) was performed to study the stress and strain at the alveolar fossa of each mouse under the same vertical and lateral stress. FEA revealed that the stress and strain at the alveolar fossa of each mouse gradually concentrated on the tooth cervix. The stress and strain at the tooth cervix gradually increased with time but were decreased at day 42. Under the same lingual loading, the maximum differences of the stress and strain at the tooth root in KO mice were greater than those in WT mice. Thus, these findings demonstrate that BMP9 could affect the biomechanical response of the alveolar fossa at the tooth root in mice with apical periodontitis. Moreover, the effects of BMP9 on the biomechanical response of the alveolar bone may be site-dependent. Overall, this work contributes to an improved understanding of the pathogenesis of apical periodontitis and may inform the development of new treatment strategies for apical periodontitis.

7.
Stem Cells Dev ; 29(16): 1059-1072, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32484035

RESUMO

Dental mesenchymal stem cells (MSCs) are recognized as a critical factor in repair of defective craniofacial bone owing to the multiple differentiation potential, the ability to regenerate distinct tissues, and the advantage that they can be easily obtained by relatively noninvasive procedures. Special AT-rich sequence-binding protein 2 (SATB2) is a nuclear matrix protein, involved in chromatin remodeling and transcriptional regulation, and has been reported to be as a positive regulator of osteoblast differentiation, bone formation, and bone regeneration in MSCs. In this study, we systematically investigated the capability of SATB2 to promote the osteogenic differentiation of periodontal ligament stem cells (PDLSCs), dental pulp stem cells (DPSCs), and stem cells from human exfoliated deciduous teeth (SHED). RNA-seq analysis and quantitative real-time PCR (RT-PCR) revealed that genes regulating osteogenic differentiation were differentially expressed among three cell types and SATB2 was found to be expressed at a relatively high level. When the three cell types overexpressed SATB2 with AdSATB2 infection, alkaline phosphatase (ALP) staining, ALP activity, Alizarin Red S staining, and quantification tended to increase with an increasing infection rate. It showed opposite results after infection with AdsiSATB2. RNA-seq analysis indicated that the expression of downstream osteogenic genes was affected by AdSATB2 infection and quantitative RT-PCR confirmed that nine osteogenic genes (Spp1, Sema7a, Atf4, Ibsp, Col1a1, Sp7, Igfbp3, Dlx3, and Alpl) were upregulated, to various extents, following SATB2 overexpression. In addition, quantitative PCR results indicated that SATB2 affected the expression of MSC markers. These results suggested an important role of SATB2 in the osteogenesis of PDLSCs, DPSCs, and SHED. Further research is warranted to investigate SATB2-mediated regulation of osteogenic differentiation and to evaluate the therapeutic use of SATB2 for the regeneration of defective craniofacial bone tissue.


Assuntos
Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Dente/citologia , Fatores de Transcrição/metabolismo , Adolescente , Biomarcadores/metabolismo , Diferenciação Celular/genética , Polpa Dentária/citologia , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Masculino , Proteínas de Ligação à Região de Interação com a Matriz/genética , Osteogênese/genética , Ligamento Periodontal/citologia , Reprodutibilidade dos Testes , Esfoliação de Dente , Dente Decíduo/citologia , Fatores de Transcrição/genética
8.
Stem Cells Dev ; 28(10): 683-694, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30816068

RESUMO

Tooth development is regulated by sequential and reciprocal epithelium-mesenchymal interactions and their related molecular signaling pathways, such as bone morphogenetic proteins (BMPs). Among the 14 types of BMPs, BMP9 (also known as growth differentiation factor 2) is one of the most potent BMPs to induce osteogenic differentiation of mesenchymal stem cells. The purpose of this study was to examine potential roles of BMP9 signaling in tooth development. First, we detected the expression pattern of BMP9 in tooth germ during postnatal tooth development, and we found that BMP9 was widely expressed in odontoblasts, ameloblasts, dental pulp cells, and osteoblasts in alveolar bones. Then, we established a BMP9-KO mouse model. Gross morphological examination revealed that the tooth cusps of BMP9-KO mice were significantly abraded with shorter roots. Micro-computed tomography and three-dimensional reconstruction analysis indicated that the first molars of the BMP9-KO mice exhibited a reduced thickness dentin, enlarged pulp canals, and shortened roots, resembling the phenotypes of the common hereditary dental disease dentinogenesis imperfecta. Further, the alveolar bone of the BMP9-KO mutants was found to be shorter and had a decreased mineral density and trabecular thickness and bone volume fraction compared with that of the wild-type control. Mechanistically, we demonstrated that both dentin sialophosphoprotein and dentin matrix protein 1 were induced in dental stem cells by BMP9, whereas their expression was reduced when BMP9 was silenced. Further studies are required to determine whether loss of or decreased BMP9 expression is clinically associated with dentinogenesis imperfecta. Collectively, our results strongly suggest that BMP9 may play an important role in regulating dentinogenesis and tooth development. Further research is recommended into the therapeutic uses of BMP9 to regenerate traumatized and diseased tissues and for the bioengineering of replacement teeth.


Assuntos
Dentina/crescimento & desenvolvimento , Fator 2 de Diferenciação de Crescimento/genética , Odontogênese/fisiologia , Dente/crescimento & desenvolvimento , Ameloblastos/metabolismo , Animais , Diferenciação Celular , Polpa Dentária/metabolismo , Dentinogênese Imperfeita/genética , Transição Epitelial-Mesenquimal/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/genética , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Odontoblastos/metabolismo , Osteoblastos/metabolismo , Osteogênese/fisiologia , Fosfoproteínas/metabolismo , Sialoglicoproteínas/metabolismo , Germe de Dente/metabolismo
9.
ACS Appl Mater Interfaces ; 11(9): 8749-8762, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30734555

RESUMO

Effective bone tissue engineering can restore bone and skeletal functions that are impaired by traumas and/or certain medical conditions. Bone is a complex tissue and functions through orchestrated interactions between cells, biomechanical forces, and biofactors. To identify ideal scaffold materials for effective mesenchymal stem cell (MSC)-based bone tissue regeneration, here we develop and characterize a composite nanoparticle hydrogel by combining carboxymethyl chitosan (CMCh) and amorphous calcium phosphate (ACP) (designated as CMCh-ACP hydrogel). We demonstrate that the CMCh-ACP hydrogel is readily prepared by incorporating glucono δ-lactone (GDL) into an aqueous dispersion or rehydrating the acidic freeze-dried nanoparticles in a pH-triggered controlled-assembly fashion. The CMCh-ACP hydrogel exhibits excellent biocompatibility and effectively supports MSC proliferation and cell adhesion. Moreover, while augmenting BMP9-induced osteogenic differentiation, the CMCh-ACP hydrogel itself is osteoinductive and induces the expression of osteoblastic regulators and bone markers in MSCs in vitro. The CMCh-ACP scaffold markedly enhances the efficiency and maturity of BMP9-induced bone formation in vivo, while suppressing bone resorption occurred in long-term ectopic osteogenesis. Thus, these results suggest that the pH-responsive self-assembled CMCh-ACP injectable and bioprintable hydrogel may be further exploited as a novel scaffold for osteoprogenitor-cell-based bone tissue regeneration.


Assuntos
Bioimpressão , Hidrogéis/química , Engenharia Tecidual , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Regeneração Óssea , Osso e Ossos/fisiologia , Fosfatos de Cálcio/química , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quitosana/análogos & derivados , Quitosana/química , Fatores de Diferenciação de Crescimento/genética , Fatores de Diferenciação de Crescimento/metabolismo , Humanos , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/química , Osteogênese/efeitos dos fármacos
10.
J Biomed Mater Res A ; 106(6): 1743-1752, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29396921

RESUMO

There is a need in orthopaedic and craniomaxillofacial surgeries for materials that are easy to handle and apply to a surgical site, can fill and fully conform to the bone defect, and can promote the formation of new bone tissue. Thermoresponsive polymers that undergo liquid to gel transition at physiological temperature can potentially be used to meet these handling and shape-conforming requirements. However, there are no reports on their capacity to induce in vivo bone formation. The objective of this research was to investigate whether the functionalization of the thermoresponsive, antioxidant macromolecule poly(poly-ethyleneglycol citrate-co-N-isopropylacrylamide) (PPCN), with strontium, phosphate, and/or the cyclic RGD peptide would render it a hydrogel with osteoinductive properties. We show that all formulations of functionalized PPCN retain thermoresponsive properties and can induce osteodifferentiation of human mesenchymal stem cells without the need for exogenous osteogenic supplements. PPCN-Sr was the most osteoinductive formulation in vitro and produced robust localized mineralization and osteogenesis in subcutaneous and intramuscular tissue in a mouse model. Strontium was not detected in any of the major organs. Our results support the use of functionalized PPCN as a valuable tool for the recruitment, survival, and differentiation of cells critical to the development of new bone and the induction of bone formation in vivo. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1743-1752, 2018.


Assuntos
Ácido Cítrico/análogos & derivados , Células-Tronco Mesenquimais/citologia , Osteogênese , Peptídeos Cíclicos/química , Fosfatos/química , Estrôncio/química , Alicerces Teciduais/química , Tecido Adiposo/citologia , Antioxidantes/química , Materiais Biocompatíveis/química , Regeneração Óssea , Adesão Celular , Linhagem Celular , Proliferação de Células , Células Cultivadas , Fibroblastos/citologia , Humanos , Células-Tronco/citologia , Temperatura
11.
Med Phys ; 34(12): 4923-33, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18196817

RESUMO

Cone-beam microcomputed tomography (microCT) is one of the most popular choices for small animal imaging which is becoming an important tool for studying animal models with transplanted diseases. Region-of-interest (ROI) imaging techniques in CT, which can reconstruct an ROI image from the projection data set of the ROI, can be used not only for reducing imaging-radiation exposure to the subject and scatters to the detector but also for potentially increasing spatial resolution of the reconstructed images. Increasing spatial resolution in microCT images can facilitate improved accuracy in many assessment tasks. A method proposed previously for increasing CT image spatial resolution entails the exploitation of the geometric magnification in cone-beam CT. Due to finite detector size, however, this method can lead to data truncation for a large geometric magnification. The Feldkamp-Davis-Kress (FDK) algorithm yields images with artifacts when truncated data are used, whereas the recently developed backprojection filtration (BPF) algorithm is capable of reconstructing ROI images without truncation artifacts from truncated cone-beam data. We apply the BPF algorithm to reconstructing ROI images from truncated data of three different objects acquired by our circular cone-beam microCT system. Reconstructed images by use of the FDK and BPF algorithms from both truncated and nontruncated cone-beam data are compared. The results of the experimental studies demonstrate that, from certain truncated data, the BPF algorithm can reconstruct ROI images with quality comparable to that reconstructed from nontruncated data. In contrast, the FDK algorithm yields ROI images with truncation artifacts. Therefore, an implication of the studies is that, when truncated data are acquired with a configuration of a large geometric magnification, the BPF algorithm can be used for effective enhancement of the spatial resolution of a ROI image.


Assuntos
Aumento da Imagem/instrumentação , Tomografia Computadorizada de Feixe Cônico Espiral , Algoritmos , Animais , Extremidades/patologia , Fibrossarcoma/diagnóstico por imagem , Humanos , Camundongos , Osteossarcoma/diagnóstico por imagem , Imagens de Fantasmas , Polimetil Metacrilato
12.
PLoS One ; 12(3): e0172327, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28249039

RESUMO

Large skeletal defects caused by trauma, congenital malformations, and post-oncologic resections of the calvarium present major challenges to the reconstructive surgeon. We previously identified BMP-9 as the most osteogenic BMP in vitro and in vivo. Here we sought to investigate the bone regenerative capacity of murine-derived calvarial mesenchymal progenitor cells (iCALs) transduced by BMP-9 in the context of healing critical-sized calvarial defects. To accomplish this, the transduced cells were delivered to the defect site within a thermoresponsive biodegradable scaffold consisting of poly(polyethylene glycol citrate-co-N-isopropylacrylamide mixed with gelatin (PPCN-g). A total of three treatment arms were evaluated: PPCN-g alone, PPCN-g seeded with iCALs expressing GFP, and PPCN-g seeded with iCALs expressing BMP-9. Defects treated only with PPCN-g scaffold did not statistically change in size when evaluated at eight weeks postoperatively (p = 0.72). Conversely, both animal groups treated with iCALs showed significant reductions in defect size after 12 weeks of follow-up (BMP9-treated: p = 0.0025; GFP-treated: p = 0.0042). However, H&E and trichrome staining revealed more complete osseointegration and mature bone formation only in the BMP9-treated group. These results suggest that BMP9-transduced iCALs seeded in a PPCN-g thermoresponsive scaffold is capable of inducing bone formation in vivo and is an effective means of creating tissue engineered bone for critical sized defects.


Assuntos
Consolidação da Fratura , Fatores de Diferenciação de Crescimento , Células-Tronco Mesenquimais/metabolismo , Osseointegração , Crânio/lesões , Alicerces Teciduais/química , Transdução Genética , Animais , Linhagem Celular , Gelatina/química , Fator 2 de Diferenciação de Crescimento , Fatores de Diferenciação de Crescimento/biossíntese , Fatores de Diferenciação de Crescimento/genética , Humanos , Camundongos , Polietilenoglicóis/química
13.
Sci Rep ; 6: 39174, 2016 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-27982110

RESUMO

Effective treatment of osteomyelitis remains a formidable clinical challenge. The rapid emergence of multidrug-resistant bacteria has renewed interest in developing antimicrobial biomaterials using antiseptic silver ions to treat osteomyelitis. However, inadequate local retention and severe cytotoxic effects have limited the clinical use of ionic silver for bone grafts. We recently developed novel porous nano-hydroxyapatite/polyamide 66 (nHP66)-based nanoscaffold materials containing varied concentrations of silver ions (Ag+) (TA-nHAPA66) and oxidized titanium (TiO2), which was added as a second binary element to enhance antibacterial activity and biocompatibility. In this study, we establish a large cohort of rabbit model of experimental osteomyelitis and investigate the in vivo antimicrobial and therapeutic effects of TA-nHP66 biomaterials and their in vivo silver release kinetics. We find the TA-nHP66 scaffolds exhibit potent antibacterial activities against E. coli and S. aureus, support cell adhesion and cell proliferation of pre-osteoblasts, and stimulate osteogenic regulator/marker expression. Moreover, the TA2-nHP66 scaffold exerts potent antibacterial/anti-inflammation effects in vivo and promotes bone formation at the lesion site of osteomyelitis. We further demonstrate that TA2-nHP66 exhibits excellent biosafety profile without apparent systemic toxicities. Therefore, the TA-nHP66 scaffold biomaterials may be further explored as an effective adjuvant therapy for infected bone defects and/or osteomyelitis debridement.


Assuntos
Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/farmacologia , Durapatita/química , Nanopartículas/química , Nylons/química , Prata/química , Titânio/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Biomarcadores/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Nanopartículas/uso terapêutico , Nanopartículas/toxicidade , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteomielite/tratamento farmacológico , Osteomielite/metabolismo , Osteomielite/patologia , Osteomielite/veterinária , Coelhos , Staphylococcus aureus/efeitos dos fármacos
14.
Genes Dis ; 3(4): 263-276, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28491933

RESUMO

Tooth is a complex hard tissue organ and consists of multiple cell types that are regulated by important signaling pathways such as Wnt and BMP signaling. Serious injuries and/or loss of tooth or periodontal tissues may significantly impact aesthetic appearance, essential oral functions and the quality of life. Regenerative dentistry holds great promise in treating oral/dental disorders. The past decade has witnessed a rapid expansion of our understanding of the biological features of dental stem cells, along with the signaling mechanisms governing stem cell self-renewal and differentiation. In this review, we first summarize the biological characteristics of seven types of dental stem cells, including dental pulp stem cells, stem cells from apical papilla, stem cells from human exfoliated deciduous teeth, dental follicle precursor cells, periodontal ligament stem cells, alveolar bone-derived mesenchymal stem cells (MSCs), and MSCs from gingiva. We then focus on how these stem cells are regulated by bone morphogenetic protein (BMP) and/or Wnt signaling by examining the interplays between these pathways. Lastly, we analyze the current status of dental tissue engineering strategies that utilize oral/dental stem cells by harnessing the interplays between BMP and Wnt pathways. We also highlight the challenges that must be addressed before the dental stem cells may reach any clinical applications. Thus, we can expect to witness significant progresses to be made in regenerative dentistry in the coming decade.

15.
Biomed Mater ; 11(2): 025021, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27097687

RESUMO

Successful bone tissue engineering requires at the minimum sufficient osteoblast progenitors, efficient osteoinductive factors, and biocompatible scaffolding materials. We previously demonstrated that bone morphogenetic protein 9 (BMP9) is one of the most potent factors in inducing osteogenic differentiation of mesenchymal stem cells (MSCs). Here, we investigated the potential use of a biodegradable citrate-based thermosensitive macromolecule, poly(polyethyleneglycol citrate-co-N-isopropylacrylamide) (PPCN) mixed with gelatin (PPCNG) as a scaffold for the delivery of BMP9-stimulated MSCs to promote localized bone formation. The addition of gelatin to PPCN effectively enhanced the cell adhesion and survival properties of MSCs entrapped within the gel in 3D culture. Using the BMP9-transduced MSC line immortalized mouse embryonic fibroblasts (iMEFs), we found that PPCNG facilitated BMP9-induced osteogenic differentiation of iMEFs in vivo and promoted the formation of well-ossified and vascularized trabecular bone-like structures in a mouse model of ectopic bone formation. Histologic evaluation revealed that vascularization of the bony masses retrieved from the iMEFs + PPCNG group was significantly more pronounced than that of the direct cell injection group. Accordingly, vascular endothelial growth factor (VEGF) expression was shown to be significantly higher in the bony masses recovered from the iMEFs + PPCNG group. Taken together, our results suggest that PPCNG may serve as a novel biodegradable and injectable scaffold and carrier for gene and cell-based bone tissue engineering.


Assuntos
Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Osteogênese/fisiologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Resinas Acrílicas/química , Animais , Materiais Biocompatíveis/química , Adesão Celular , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular , Citratos/química , Feminino , Gelatina/química , Fator 2 de Diferenciação de Crescimento , Fatores de Diferenciação de Crescimento/genética , Fatores de Diferenciação de Crescimento/fisiologia , Células HEK293 , Humanos , Teste de Materiais , Melanoma Experimental , Camundongos , Camundongos Nus , Polietilenoglicóis/química , Temperatura , Alicerces Teciduais/química , Transdução Genética
16.
Biomaterials ; 39: 145-54, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25468367

RESUMO

Dental pulp/dentin regeneration using dental stem cells combined with odontogenic factors may offer great promise to treat and/or prevent premature tooth loss. Here, we investigate if BMP9 and Wnt/ß-catenin act synergistically on odontogenic differentiation. Using the immortalized SCAPs (iSCAPs) isolated from mouse apical papilla tissue, we demonstrate that Wnt3A effectively induces early osteogenic marker alkaline phosphatase (ALP) in iSCAPs, which is reduced by ß-catenin knockdown. While Wnt3A and BMP9 enhance each other's ability to induce ALP activity in iSCAPs, silencing ß-catenin significantly diminishes BMP9-induced osteo/odontogenic differentiation. Furthermore, silencing ß-catenin reduces BMP9-induced expression of osteocalcin and osteopontin and in vitro matrix mineralization of iSCAPs. In vivo stem cell implantation assay reveals that while BMP9-transduced iSCAPs induce robust ectopic bone formation, iSCAPs stimulated with both BMP9 and Wnt3A exhibit more mature and highly mineralized trabecular bone formation. However, knockdown of ß-catenin in iSCAPs significantly diminishes BMP9 or BMP9/Wnt3A-induced ectopic bone formation in vivo. Thus, our results strongly suggest that ß-catenin may play an important role in BMP9-induced osteo/ondontogenic signaling and that BMP9 and Wnt3A may act synergistically to induce osteo/odontoblastic differentiation of iSCAPs. It's conceivable that BMP9 and/or Wnt3A may be explored as efficacious biofactors for odontogenic regeneration and tooth engineering.


Assuntos
Papila Dentária/citologia , Fatores de Diferenciação de Crescimento/farmacologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sinergismo Farmacológico , Feminino , Gossipol/análogos & derivados , Gossipol/farmacologia , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Odontogênese , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt
17.
Stem Cells Dev ; 23(12): 1405-16, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24517722

RESUMO

Dental pulp/dentin regeneration using dental stem cells combined with odontogenic factors may offer great promise to treat and/or prevent premature tooth loss. We previously demonstrated that bone morphogenetic protein 9 (BMP9) is one of the most potent factors in inducing bone formation. Here, we investigate whether BMP9 can effectively induce odontogenic differentiation of the stem cells from mouse apical papilla (SCAPs). Using a reversible immortalization system expressing SV40 T flanked with Cre/loxP sites, we demonstrate that the SCAPs can be immortalized, resulting in immortalized SCAPs (iSCAPs) that express mesenchymal stem cell markers. BMP9 upregulates Runx2, Sox9, and PPARγ2 and odontoblastic markers, and induces alkaline phosphatase activity and matrix mineralization in the iSCAPs. Cre-mediated removal of SV40 T antigen decreases iSCAP proliferation. The in vivo stem cell implantation studies indicate that iSCAPs can differentiate into bone, cartilage, and, to lesser extent, adipocytes upon BMP9 stimulation. Our results demonstrate that the conditionally iSCAPs not only maintain long-term cell proliferation but also retain the ability to differentiate into multiple lineages, including osteo/odontoblastic differentiation. Thus, the reversibly iSCAPs may serve as an important tool to study SCAP biology and SCAP translational use in tooth engineering. Further, BMP9 may be explored as a novel and efficacious factor for odontogenic regeneration.


Assuntos
Diferenciação Celular/genética , Papila Dentária/crescimento & desenvolvimento , Fator 2 de Diferenciação de Crescimento/genética , Odontogênese , Animais , Proliferação de Células/genética , Papila Dentária/citologia , Regulação da Expressão Gênica no Desenvolvimento , Fator 2 de Diferenciação de Crescimento/biossíntese , Camundongos , Odontoblastos/metabolismo , Regeneração , Células-Tronco/metabolismo
18.
PLoS One ; 9(3): e92908, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24658746

RESUMO

Mesenchymal stem cells (MSCs) are multipotent progenitors, which can undergo self-renewal and give rise to multi-lineages. A great deal of attentions have been paid to their potential use in regenerative medicine as potential therapeutic genes can be introduced into MSCs. Genetic manipulations in MSCs requires effective gene deliveries. Recombinant adenoviruses are widely used gene transfer vectors. We have found that although MSCs can be infected in vitro by adenoviruses, high virus titers are needed to achieve high efficiency. Here, we investigate if the commonly-used cationic polymer Polybrene can potentiate adenovirus-mediated transgene delivery into MSCs, such as C2C12 cells and iMEFs. Using the AdRFP adenovirus, we find that AdRFP transduction efficiency is significantly increased by Polybrene in a dose-dependent fashion peaking at 8 µg/ml in C2C12 and iMEFs cells. Quantitative luciferase assay reveals that Polybrene significantly enhances AdFLuc-mediated luciferase activity in C2C12 and iMEFs at as low as 4 µg/ml and 2 µg/ml, respectively. FACS analysis indicates that Polybrene (at 4 µg/ml) increases the percentage of RFP-positive cells by approximately 430 folds in AdRFP-transduced iMEFs, suggesting Polybrene may increase adenovirus infection efficiency. Furthermore, Polybrene can enhance AdBMP9-induced osteogenic differentiation of MSCs as early osteogenic marker alkaline phosphatase activity can be increased more than 73 folds by Polybrene (4 µg/ml) in AdBMP9-transduced iMEFs. No cytotoxicity was observed in C2C12 and iMEFs at Polybrene up to 40 µg/ml, which is about 10-fold higher than the effective concentration required to enhance adenovirus transduction in MSCs. Taken together, our results demonstrate that Polybrene should be routinely used as a safe, effective and inexpensive augmenting agent for adenovirus-mediated gene transfer in MSCs, as well as other types of mammalian cells.


Assuntos
Adenoviridae/genética , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Brometo de Hexadimetrina/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Transdução Genética , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Citometria de Fluxo , Expressão Gênica , Genes Reporter , Humanos , Camundongos , Transgenes
19.
J Biomed Mater Res A ; 101(12): 3542-50, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23629940

RESUMO

Articular cartilage lesions in the knee are common injuries. Chondrocyte transplant represents a promising therapeutic modality for articular cartilage injuries. Here, we characterize the viability and transgene expression of articular chondrocytes cultured in three-dimensional scaffolds provided by four types of carriers. Articular chondrocytes are isolated from rabbit knees and cultured in four types of scaffolds: type I collagen sponge, fibrin glue, hyaluronan, and open-cell polylactic acid (OPLA). The cultured cells are transduced with adenovirus expressing green fluorescence protein (AdGFP) and luciferase (AdGL3-Luc). The viability and gene expression in the chondrocytes are determined with fluorescence microscopy and luciferase assay. Cartilage matrix production is assessed by Alcian blue staining. Rabbit articular chondrocytes are effectively infected by AdGFP and exhibited sustained GFP expression. All tested scaffolds support the survival and gene expression of the infected chondrocytes. However, the highest transgene expression is observed in the OPLA carrier. At 4 weeks, Alcian blue-positive matrix materials are readily detected in OPLA cultures. Thus, our results indicate that, while all tested carriers can support the survival of chondrocytes, OPLA supports the highest transgene expression and is the most conductive scaffold for matrix production, suggesting that OPLA may be a suitable scaffold for cell-based gene therapy of articular cartilage repairs.


Assuntos
Cartilagem Articular/patologia , Condrócitos/citologia , Condrócitos/metabolismo , Terapia Genética , Alicerces Teciduais/química , Cicatrização , Adenoviridae/metabolismo , Animais , Cartilagem Articular/efeitos dos fármacos , Separação Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Condrócitos/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Transferência de Genes , Vetores Genéticos/metabolismo , Células HEK293 , Humanos , Ácido Láctico/farmacologia , Masculino , Poliésteres , Polímeros/farmacologia , Coelhos , Recombinação Genética , Transgenes/genética , Cicatrização/efeitos dos fármacos
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