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1.
J Biomed Nanotechnol ; 15(12): 2351-2362, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748016

RESUMO

Hydrogels have been widely used to mimic the biochemical and mechanical environments of native extracellular matrices for cell culture and tissue engineering. Among them, self-assembling peptide hydrogels are of special interest thanks to their great biocompatibility, designability and convenient preparation procedures. In pioneering studies, self-assembling peptide hydrogels have been used for the culture of bone marrow cells. However, the low mechanical stability of peptide hydrogels seems to be a drawback for these applications, as bone marrow cells prefer hard substrates for osteogenic differentiation. In this work, we explored the use of hydroxyapatite (HAP)-peptide hybrid hydrogels for three-dimensional (3D) culture and differentiation of osteogenic MC3T3-E1 cells. We used HAP nanoparticles as crosslinkers to increase the mechanical stability of peptide hydrogels. Meanwhile, HAP provided unique chemical cues to promote the differentiation of osteoblasts. A phosphate group was introduced to the self-assembling peptide so that the peptide fibers could bind to HAP nanoparticles specifically and strongly. Rheological characterization indicated that the hybrid hydrogels were mechanically more stable than the hydrogels containing only peptides and can be used for long term cell culture. Moreover, the hydrogels were biocompatible and showed very low cytotoxicity. The favorable mechanical properties of the hybrid hydrogels and the chemical properties of HAP synergistically supported the differentiation of MC3T3-E1 cells. Based on these characterizations, we believe that these hybrid hydrogels can potentially be used as scaffolds for cartilage and bone regeneration in the future.


Assuntos
Nanopartículas , Osteoblastos , Diferenciação Celular , Durapatita , Hidrogéis , Osteogênese , Peptídeos , Engenharia Tecidual , Tecidos Suporte
2.
Indian J Dent Res ; 30(4): 558-567, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31745053

RESUMO

Background and Objective: Various types of osteoconductive graft materials are used for the management of alveolar bone defects arising out of periodontal disease. Inorganic, self-setting, bioactive bone cements are suggested to be most appropriate because they can conformally fill the bone defect and resorb progressively along with the regeneration of the host site. A new calcium sulfate-based bioactive bone cement (BioCaS) is developed, having simplicity and effectiveness for bone grafting applications. The response of primary human periodontal ligament (hPDL) cells to this material is investigated through in vitro cell culture model so as to qualify it for the repair of periodontal infrabony defects. Method: The BioCaS was designed as powder-liquid combination with in-house synthesized high purity calcium sulfate hemihydrate incorporating hydrogen orthophosphate ions. hPDL cells were isolated, cultured and characterized using optimized primary cell culture techniques. The cytotoxicity and cytocompatibility of the BioCaS samples were evaluated using the hPDL cells, with hydroxyapatite ceramic material as control. Osteogenic differentiation of the hPDL cells in presence of BioCaS was also evaluated using Alizarin red staining, Alizarin red assay, Von Kossa staining and Masson's trichrome staining. Results: The primary cell culture techniques yielded a healthy population of periodontal ligament cells, with fibroblast morphology and characteristic marker expressions. The hPDL cells exhibited good viability, adhesion and spreading to the BioCaS cement in comparison to sintered hydroxyapatite. In addition, the cells differentiated to osteogenic lineage in the presence of the BioCaS cement, without extraneous osteogenic supplements, confirming the inherent bioactivity of the cement. Conclusion: The new BioCaS cement is a potential candidate for the repair of periodontal defects.


Assuntos
Cimentos para Ossos , Sulfato de Cálcio , Cemento Dentário , Humanos , Osteogênese , Ligamento Periodontal
3.
Cell Physiol Biochem ; 53(5): 832-850, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31703162

RESUMO

BACKGROUND/AIMS: Runt-related transcription factor 2 (Runx2) is a master regulator of osteogenic differentiation, but most of the direct downstream targets of RUNX2 during osteogenesis are unknown. Likewise, High-temperature requirement factor A1 (HTRA1) is a serine protease expressed in bone, yet the role of Htra1 during osteoblast differentiation remains elusive. We investigated the role of Htra1 in osteogenic differentiation and the transcriptional regulation of Htra1 by RUNX2 in primary mouse mesenchymal progenitor cells. METHODS: Overexpression of Htra1 was carried out in primary mouse mesenchymal progenitor cells to evaluate the extent of osteoblast differentiation. Streptavidin agarose pulldown assay, chromatin immunoprecipitation assay, and dual luciferase assay were carried out to investigate the interaction of RUNX2 protein at the Htra1 promoter during osteoblast differentiation. RESULTS: Overexpression of Htra1 increased the production of mineralized bone matrix, upregulating several osteoblast genes, such as Sp7 transcription factor (Sp7) and Alkaline phosphatase, liver/bone/kidney (Alpl). In addition, Htra1 upregulated osteogenesis-related signalling genes, such as Fibroblast growth factor 9 (Fgf9) and Vascular endothelial growth factor A (Vegfa). A series of experiments confirmed Htra1 as a direct RUNX2 transcriptional target. Overexpression of Runx2 resulted in the upregulation of Htra1 mRNA and protein. Chromatin immunoprecipitation and streptavidin agarose pull-down assays showed that RUNX2 binds a proximal -400 bp region of the Htra1 promoter during osteogenic differentiation. Dual luciferase assays confirmed that RUNX2 activates the proximal Htra1 promoter during osteogenic differentiation. Mutation of putative RUNX2 binding sites revealed that RUNX2 interacts with the Htra1 promoter at -252 bp and -84 bp to induce Htra1 expression. CONCLUSION: We demonstrate that Htra1 is a positive regulator of osteogenic differentiation, showing for the first time that Htra1 is a direct downstream target of RUNX2.


Assuntos
Diferenciação Celular , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Serina Peptidase 1 de Requerimento de Alta Temperatura A/metabolismo , Animais , Sítios de Ligação , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Fator 9 de Crescimento de Fibroblastos/metabolismo , Serina Peptidase 1 de Requerimento de Alta Temperatura A/genética , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteogênese , Regiões Promotoras Genéticas , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(5): 469-475, 2019 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-31721491

RESUMO

OBJECTIVE: This study aims to compare the osteogenic differentiation capability of stem cells derived from human inflammatory periodontal ligament tissues (iPDLSCs) with those of stem cells derived from healthy periodontal ligament tissues (hPDLSCs). Both types of tissues were induced by stromal cell derived factor (SDF-1) in vitro. METHODS: iPDLSCs and hPDLSCs were primarily cultured by tissue digestion method and purified by limited dilution cloning. The cells were passaged and identified by stem cell surface marker expression through flow cytometry. Then, we used thiazolyl blue tetrazolium bromide to detect and compare the proliferation capabilities of the iPDLSCs and hPDLSCs. Express of bone volumes were detected by alizarin red staining after SDF-1 was added to the cells. Using alkaline phosphatase, we evaluated the osteogenic differentiation capability of the cells induced by SDF-1. The expression levels of the osteogenesis-related genes of the cells induced by SDF-1 were determined by reverse transcription-polymerase chain reaction. RESULTS: After purification, both iPDLSCs and hPDLSCs expressed stem cell markers. hPDLCSs had a higher proliferation capability than iPDLSCs. Osteogenesis-related genes had higher expression levels in the cells induced by SDF-1 than in those without induction (P<0.05). SDF-1 at 50 and 200 ng·mL⁻¹ concentration greatly affected the differen-tiation capabilities of iPDLSCs and hPDLSCs respectively. CONCLUSIONS: iPDLSCs and hPDLSCs had osteogenic differentia-tion capability. The level of osteogenic differentiation in normal and inflamed periodontal ligament stem cells increases after SDF-1 induction.


Assuntos
Osteogênese , Ligamento Periodontal , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Células-Tronco , Células Estromais
5.
J Environ Pathol Toxicol Oncol ; 38(3): 271-283, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679313

RESUMO

Certain mechanical stimuli-particularly low-magnitude, high-frequency vibration-could induce bone marrow stem cell osteogenic differentiation and promote bone formation via Wnt signaling pathway, although the molecular mechanism is still unclear. In this study, we found that miR-335-5p is significantly upregulated after low-magnitude, high-frequency vibration, which suppresses the expression of the Wnt signaling inhibitor Dickkopf-related protein 1. Inhibition of miR-335-5p greatly reduced the osteogenic differentiation. Furthermore, the increase of miR-335-5p level was also confirmed in vivo after LMHF vibration in rabbit. Our study elucidates the prominent role of miRNAs that links the LMHF vibration and osteogenic differentiation.


Assuntos
Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Osteogênese/fisiologia , Vibração/efeitos adversos , Animais , Diferenciação Celular/fisiologia , Masculino , MicroRNAs/metabolismo , Coelhos
6.
Zhongguo Gu Shang ; 32(9): 853-860, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31615185

RESUMO

OBJECTIVE: To explore the effect of lentivirus-mediated BMP-2 overexpression plasmid transfection into bone marrow mesenchymal stem cells and silk fibroin scaffold on osteoblast transformation. METHODS: The lentivirus BMP-2 overexpression vector was constructed, bone marrow mesenchymal stem cells were cultured, and the combined culture system of nuclear scaffolds was constructed. Alizarin red staining and alkaline phosphatase staining were used to detect the osteogenic transformation of bone marrow mesenchymal stem cells in vitro. Ten New Zealand white rabbits, weighing 3.2 to 4.5 kg(averaging 3.9 kg), aged (2.89±0.45) years old, were selected to construct the rabbit tibial defect model by drilling a conical tibial defect (5 mm in length, 2 mm in width and 3 mm in depth) with an oral drill. The repair of the tibial defect in the animal model was observed by HE staining. The experimental group was implanted with silk fibroin scaffold + BMP-2 overexpression vector bone marrow mesenchymal stem cell complex, while the negative control group was implanted with silk fibroin scaffold+non-transfected bone marrow mesenchymal stem cell complex. RESULTS: Compared with the control group(silk fibroin scaffold+non-transfected bone marrow mesenchymal stem cells), the number of adherent cells on the surface of the scaffold in the experimental group(silk fibroin scaffold+transfected BMP-2 overexpression vector BMP-2 complex) increased significantly. Compared with the control group, the ECM secretion in the experimental group increased significantly. EDX analysis showed that the content of calcium ion was 0.22% in the control group and 0.86% in the experimental group, which showed that the ability of inducing calcium ion formation in the experimental group was stronger than that in the control group. Alizarin red staining of calcium nodules showed that there was no obvious change in the naked eye of the control group, and a small amount of calcium nodules could be seen under the microscope. In the experimental group, obvious red area staining was observed by naked eye, and a large number of calcium nodules were observed by microscopy. The results of alkaline phosphatase staining showed that there was no obvious change in the naked eye of the control group, and no obvious change in the microscopic observation. In the experimental group, purple area staining was observed by naked eyes, and ALP staining was strongly positive by microscopy. The combined culture system of silk fibroin scaffold and bone marrow mesenchymal stem cells can repair cartilage defects. The repair effect of BMP-2 bone marrow mesenchymal stem cells after transfection is obviously better than that of non-transfection group. HE staining showed that inflammatory cells decreased and scaffolds disappeared slightly in the control group. In the experimental group, inflammatory cells were significantly reduced, scaffolds disappeared and angiogenesis was observed. CONCLUSIONS: Lentivirus-mediated BMP-2 overexpression plasmid can promote BMSC to differentiate into osteocytes and secrete more extracellular matrix containing Ca²âº to promote bone defect repair.


Assuntos
Células-Tronco Mesenquimais , Animais , Células da Medula Óssea , Proteína Morfogenética Óssea 2 , Células Cultivadas , Fibroínas , Lentivirus , Osteoblastos , Osteogênese , Plasmídeos , Coelhos , Transfecção
7.
J Appl Oral Sci ; 27: e20180476, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596364

RESUMO

OBJECTIVES: Miniscrew has been frequently used, considering that anchorage control is a critical point in orthodontic treatment, and its failure, the main adverse problem. Using two groups of stable (successful) and unstable (failed) mini-implants, this in vivo study aimed to quantify proinflammatory cytokines IL-1 α, IL-6, IL-17, and TNF-α and osteoclastogenesis marker RANK, RANKL, and OPG in gingival tissue, using the real-time polymerase chain reaction technique. METHODOLOGY: Thirteen patients of both sexes (11-49 years old) under orthodontic treatment were selected, obtaining 11 successful and 7 failed mini-implants. The mini-implants were placed and removed by the same surgeon, in both jaws. The mean time of permanence in the mouth was 29.4 months for successful and 7.6 months for failed mini-implants. At removal time, peri-mini-implant gingival tissue samples were collected and processed for quantification of the proinflammatory cytokines and osteoclastogenesis markers. Nonparametric Wilcoxon rank-sum test considering the clusters and Kruskal-Wallis test were used for statistical analysis (α=0.05). RESULTS: No significant difference (p>0.05) was observed between the groups for either quantification of cytokines or osteoclastogenesis markers, except for IL-6 (p<0.05). CONCLUSIONS: It may be concluded that the expression of IL-1α, IL-17, TNF-α, RANK, RANKL, and OPG in peri-implant gingival tissue were not determinant for mini-implant stability loss, but the higher IL-6 expression could be associated with mini-implant failure.


Assuntos
Citocinas/análise , Implantes Dentários/efeitos adversos , Gengivite/patologia , Procedimentos de Ancoragem Ortodôntica/efeitos adversos , Osteogênese/fisiologia , Peri-Implantite/patologia , Adolescente , Adulto , Perda do Osso Alveolar , Biomarcadores/análise , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoprotegerina/análise , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Estatísticas não Paramétricas , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
8.
J Appl Oral Sci ; 27: e20180574, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596365

RESUMO

OBJECTIVES: Hypertension is one of the main causes of premature death in the world; also, it is associated with several bone alterations. Preclinical studies have demonstrated delayed alveolar bone healing in hypertensive rats. However, losartan has been favorable for consolidation of bone grafts and reduction in active periodontitis. Therefore, losartan is suggested to be effective in bone formation stages, as well as in the synthesis of matrix proteins and mineralization. To evaluate the alveolar bone dynamics in hypertensive rats treated with losartan by laser confocal microscopy and histological analysis. METHODOLOGY: Thirty-two rats, 16 spontaneously hypertensive rats (SHR) and 16 Wistar albinus rats, treated or not with losartan (30 mg/kg/day) were used. Calcein fluorochrome at 21 days and alizarin red fluorochrome at 49 days were injected in rats (both 20 mg/kg). The animals were submitted to euthanasia 67 days after treatment, and then the right maxilla was removed for laser confocal microscopy analysis and the left maxilla for histological analysis. RESULTS: This study showed a greater calcium marking in normotensive animals treated with losartan in relation to the other groups. Laser confocal microscopy parameters showed higher values of bone volume formed, mineralized surface, active surface of mineralization and bone formation rate in normotensive animals treated with losartan. However, a smaller mineralized surface was observed in all hypertensive animals. CONCLUSION: Losartan can improve bone mineralization parameters under normal physiological conditions, but the same anabolic effect does not occur under hypertension.


Assuntos
Processo Alveolar/efeitos dos fármacos , Processo Alveolar/fisiopatologia , Anti-Hipertensivos/farmacologia , Hipertensão/fisiopatologia , Losartan/farmacologia , Processo Alveolar/patologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Fluoresceínas/análise , Masculino , Microscopia Confocal , Osteogênese/efeitos dos fármacos , Ratos Endogâmicos SHR , Ratos Wistar , Reprodutibilidade dos Testes , Fatores de Tempo
9.
J Appl Oral Sci ; 27: e20180693, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596370

RESUMO

OBJECTIVES: To compare the sealing ability and biocompatibility of Biodentine with mineral trioxide aggregate (MTA) when used as root-end filling materials. METHODOLOGY: The Cell Counting Kit-8 (CCK-8) assay was used to compare the cytotoxicity of MTA and Biodentine. Twenty-one extracted teeth with a single canal were immersed in an acidic silver nitrate solution after root-end filling. Then, the volume and depth of silver nitrate that infiltrated the apical portion of the teeth were analyzed using micro-computed tomography (micro-CT). Seventy-two roots from 3 female beagle dogs were randomly distributed into 3 groups and apical surgery was performed. After six months, the volume of the bone defect surrounding these roots was analyzed using micro-CT. RESULTS: Based on the results of the CCK-8 assay, MTA and Biodentine did not show statistically significant differences in cytotoxicity (P>0.05). The volume and the depth of the infiltrated nitrate solution were greater in the MTA group than in the Biodentine group (P<0.05). The volume of the bone defect was larger in the MTA group than in the Biodentine group. However, the difference was not significant (P>0.05). The volumes of the bone defects in the MTA and Biodentine groups were smaller than the group without any filling materials (P<0.05). CONCLUSIONS: MTA and Biodentine exhibited comparable cellular biocompatibility. Biodentine showed a superior sealing ability to MTA in root-end filling. Both Biodentine and MTA promoted periradicular bone healing in beagle dog periradicular surgery models.


Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Óxidos/farmacologia , Tecido Periapical/efeitos dos fármacos , Ligamento Periodontal/efeitos dos fármacos , Materiais Restauradores do Canal Radicular/farmacologia , Tratamento do Canal Radicular/métodos , Silicatos/farmacologia , Cicatrização/efeitos dos fármacos , Adolescente , Animais , Regeneração Óssea/efeitos dos fármacos , Contagem de Células , Células Cultivadas , Cães , Combinação de Medicamentos , Humanos , Masculino , Teste de Materiais , Osteogênese/efeitos dos fármacos , Tecido Periapical/citologia , Tecido Periapical/diagnóstico por imagem , Ligamento Periodontal/diagnóstico por imagem , Reprodutibilidade dos Testes , Fatores de Tempo , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/efeitos dos fármacos , Raiz Dentária/cirurgia , Resultado do Tratamento , Microtomografia por Raio-X , Adulto Jovem
10.
Wiad Lek ; 72(9 cz 2): 1723-1726, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31622254

RESUMO

OBJECTIVE: Introduction: Chronic hyperglycemia as the main link in DM pathogenesis leads to systemic vessels and nerves lesion with chronic bone complications development consequently. The aim: To evaluate influence of hyperglycemia on reparative osteogenesis after perforated tibial fracture in rats. PATIENTS AND METHODS: Materials and methods: A total of 30 white adult rats were subdivided into two groups: 15 healthy rats in Group 1 (control) and 15 rats with alloxan induced hyperglycemia in Group 2 (investigated) and were carried out of experiment on the 10th, 20th and 30th day after the fracture. Hyperglycemia in rats was verificated as the postprandial glycemic rate ≥ 8,0 mmol/l. Tibia diaphysis fracture was modeled by a cylindrical defect with a diameter of 2 mm with portable frezer. Morphological evaluation. A complex morphological studies included histological, morphometric and immunohistochemical examination. RESULTS: Results: This is confirmed by an increase in MMP-9 expression in connective tissue, a decrease in TGF-ß expression in all phases, an increase in the expression of CD3 and CD20 and a marked decrease in the expression of all vascular markers. During hyperglycemia, incomplete blood supply to the tissues occurs, necrosis of bone and soft tissues develop in the area of the fracture, the reparative reaction slows down considerably and manifests itself in the development of fibrous and, less commonly, cartilage tissue. CONCLUSION: Conclusions: In hyperglycemia rats, there was a delay in the callus formation, a decrease in proliferation and ossification, and a slowdown in the processes of angiogenesis.


Assuntos
Diabetes Mellitus/fisiopatologia , Osteogênese , Fraturas da Tíbia/complicações , Animais , Antígenos CD20/metabolismo , Osso e Ossos , Calo Ósseo , Complexo CD3/metabolismo , Modelos Animais de Doenças , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Fisiológica , Ratos , Fator de Crescimento Transformador beta/metabolismo
11.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(5): 887-892, 2019 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-31624394

RESUMO

OBJECTIVE: To evaluate the barrier effect of an absorbable barrier membrane made by small intestinal submucosa (SIS) compared with Bio-Gide collagen membrane. METHODS: 12 healthy New Zealand male white rabbits were randomly assigned. A or B round bone defects with a depth of 2 mm and a diameter of 5 mm or 8 mm was made in each rabbit's mandibular. The following treatments were given respectively: covered with SIS membrane (S), covered with Bio-Gide membrane (G) and blank control (O). Then we got six groups: AS, AG, AO, BS, BG, and BO (n=4). After 4 weeks, the rabbits were sacrificed. The specimens were examined by naked-eye observation, new bone percentage (BV/TV) and bone mineralized density (BMD), which were measured and analyzed by Micro-CT. The data were analyzed with one-way ANOVA. RESULTS: After 4 weeks, Bio-Gide membranes were fused with the surrounding tissue while SIS membranes held the form with no significant degradation. In the AS, BS and AG groups, the absorbable membranes smoothly covered on the new bone. While in the BG group, Bio-Gide membranes collapsed to the center of the bone defects. The 3D reconstruction of Micro-CT showed that a large number of newly formed trabeculae were found in the four groups of AS, BS, AG, and BG. In the central subsidence area of the BG group, the newly formed trabeculae were sparse. However only a small amount of new bone trabecula appeared at the bottom of the defects in groups AO and BO. Micro-CT quantitative results showed that BV/TV (39.10%±0.79%) and BMD [(517.73±11.22) mg/cm3] of AS group were significantly higher than those of AO group [26.67%±1.12%, (319.81±8.00) mg/cm3] (P<0.05), and there was no significant difference between AS group and AG group [38.15%±0.91%, (518.65±7.48) mg/cm3] (P>0.05). BV/TV (34.90%±1.35%) and BMD [(409.09±8.14) mg/cm3] of BS group were significantly higher than those of BO group [23.63%±2.07%, (171.00±16.24) mg/cm3] (P < 0.05). Meanwhile, there was no significant difference between BS and BG groups [33.40%±1.06%, (412.70±8.6) mg/cm3] (P>0.05). HE staining analysis revealed that significant bone formation was achieved in the AS, AG, BS and BG groups, and trabecular bone of AS and AG groups were thicker and denser. In AO and BO group, there were scattered new bone tissues in edges of host bone, and no coarse trabecular bone formed. CONCLUSION: In the early healing of two sizes bone defects in rabbit mandibular, SIS membrane and Bio-Gide membrane have a similar barrier effect in guided bone regeneration. And SIS membrane's ability to maintain space for bone regeneration seems to be better.


Assuntos
Regeneração Óssea , Mandíbula , Implantes Absorvíveis , Animais , Masculino , Osteogênese , Coelhos , Distribuição Aleatória , Suínos , Cicatrização , Microtomografia por Raio-X
12.
Med Oral Patol Oral Cir Bucal ; 24(6): e764-e769, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655837

RESUMO

BACKGROUND: Surgical fixation of implants into bone for the correction of bone deformities or defects is a traditional approach for skeletal stabilization. Important measures of efficacy of implants include implant stability and osseointegration-the direct interaction between living bone and an implant. Osseointegration depends on successful implant placement and subsequent bone remodeling. This study utilized osseodensification drilling (OD) in a low bone density model using trabecular metal (TM) implants. MATERIAL AND METHODS: Three osteotomy sites, Regular, OD-CW (clockwise), and OD-CCW (counterclockwise), were prepared in each ilium of three female sheep. Drilling was performed at 1100rpm with saline irrigation. Trabecular metal (TM) (Zimmer, Parsippany, NJ, USA) implants measuring 3.7mm in diameter x 10mm length were placed into respective osteotomies. A three-week period post-surgery was given to allow for healing to take place after which all three sheep were euthanized and the ilia were collected. Samples were prepared, qualitatively and quantitatively analyzed using histology micrographs and image analysis software (ImageJ, NIH, Bethesda, MD). Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were quantified to evaluate the osseointegration parameters. RESULTS: All implants exhibit successful bone formation in the peri-implant environment as well as within the open spaces of the trabecular network. Osseointegration within the TM (quantified by %BIC) as a function of drilling technique was more pronounced in OD samples(p>0.05). The %BAFO however shows a significant difference (p=0.036) between the CCW and R samples. Greater bone volume and frequency of bone chips are observed in OD samples. CONCLUSION: The utilization of OD as a design for improved fixation of hardware was supported by increased levels of stability, both primary and secondary. Histological data with OD provided notably different results from those of the regular drilling method.


Assuntos
Implantes Dentários , Osteogênese , Animais , Implantação Dentária Endo-Óssea , Metais , Osseointegração , Osteotomia , Ovinos , Tantálio
13.
Prague Med Rep ; 120(2-3): 84-94, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31586507

RESUMO

Ageing is associated with the accumulation of damage to all the macromolecules within and outside cells leading to progressively more cellular and tissue defects and resulting in age-related frailty, disability and disease. As a result of the aging process the bone deteriorates in composition, structure and function. Age-related musculoskeletal losses are a major public health burden because they can cause physical disability and increased mortality. We tried to find out on a small set of old women, without risk factors for osteoporosis, what caused them the loss of bone minerals. All 492 women had just only one risk factor - the old age. Laboratory findings have shown a decreased serum C telopeptide and low serum alkaline phosphatase circulating markers, used to quantify bone resorption and formation, and very low level of vitamin D. Very low level of vitamin D that disrupted calcium absorption through the intestine, and decreased calcemia increased parathyroid hormone levels with resulting bone effect. The manifestation of physiological aging is worsening eyesight, peripheral neuropathy, depression, worsening of physical condition, skin aging, sarcopenia and bone mineral loss. Senile osteoporosis, which is not caused by known risk factors for osteoporosis, does not appear to be a separate disease, but is part of the physiological process of aging. Treatment of senile osteoporosis should be focused on the control of secondary hyperparathyroidism by administration of vitamin D and calcium. The risk of fractures in the advanced age is determined by a large number of factors ranging from hazards in the home environment to frailty and poor balance.


Assuntos
Envelhecimento/sangue , Envelhecimento/patologia , Fosfatase Alcalina/sangue , Densidade Óssea , Cálcio/metabolismo , Colágeno Tipo I/sangue , Feminino , Humanos , Osteogênese , Osteoporose/sangue , Hormônio Paratireóideo/sangue , Peptídeos/sangue , Vitamina D/sangue
14.
Int J Nanomedicine ; 14: 7475-7488, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571859

RESUMO

Background: Wear particle-induced inflammatory osteolysis and the consequent aseptic loosening constitute the leading reasons for prosthesis failure and revision surgery. Several studies have demonstrated that the macrophage polarization state and immune response play critical roles in periprosthetic osteolysis and tissue repair, but the immunomodulatory role of lithium chloride (LiCl), which has a protective effect on wear particle-induced osteolysis by suppressing osteoclasts and attenuating inflammatory responses, has never been investigated. Methods: In this work, the immunomodulatory capability of LiCl on titanium (Ti) nanoparticle-stimulated transformation of macrophage phenotypes and the subsequent effect on osteogenic differentiation were investigated. We first speculated that LiCl attenuated Ti nanoparticle-stimulated inflammation responses by driving macrophage polarization and generating an immune micro-environment to improve osteogenesis. Furthermore, a metal nanoparticle-stimulated murine air pouch inflammatory model was applied to confirm this protective effect in vivo. Results: The results revealed that metal nanoparticles significantly activate M1 phenotype (proinflammatory macrophage) expression and increase proinflammatory cytokines secretions in vitro and in vivo, whereas LiCl drives macrophages to the M2 phenotype (anti-inflammatory macrophage) and increases the release of anti-inflammatory and bone-related cytokines. This improved the osteogenic differentiation capability of rat bone marrow mesenchymal stem cells (rBMSCs). In addition, we also provided evidence that LiCl inhibits the phosphorylation of the p38 mitogen-activated protein kinase (p38) and extracellular signal-regulated kinase (ERK) pathways in wear particle-treated macrophages. Conclusion: LiCl has the immunomodulatory effects to alleviate Ti nanoparticle-mediated inflammatory reactions and enhance the osteogenic differentiation of rBMSCs by driving macrophage polarization. Thus, LiCl may be an effective therapeutic alternative for preventing and treating wear debris-induced inflammatory osteolysis.


Assuntos
Fatores Imunológicos/farmacologia , Inflamação/patologia , Cloreto de Lítio/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas Metálicas/química , Osteogênese/efeitos dos fármacos , Titânio/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Ratos
15.
Int J Nanomedicine ; 14: 7839-7849, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576127

RESUMO

Background: Nobiletin (NOB), a polymethoxy flavonoid, possesses anti-cancer and anti-inflammatory activities, has been reported that it played role in anti-osteoporosis treatment. However, previous research did not focus on practical use due to lack of hydrophilicity and cytotoxicity at high concentrations. The aim of this study was to develop a therapeutic formulation for osteoporosis based on the utilization of NOB. Methods: In this study, NOB-loaded poly(ethylene glycol)-block-poly(e-caprolactone) (NOB-PEG-PCL) was prepared by dialysis method. The effects on osteoclasts and anti-osteoporosis functions were investigated in a RANKL-induced cell model and ovariectomized (OVX) mice. Results: Dynamic light scattering and transmission electron microscopy examination results revealed that the NOB-PEG-PCL had a round shape, with a mean diameter around 124 nm. The encapsulation efficiency and drug loading were 76.34±3.25% and 7.60±0.48%, respectively. The in vitro release of NOB from NOB-PEG-PCL showed a remarkably sustained releasing characteristic and could be retained at least 48 hrs in pH 7.4 PBS. Anti-osteoclasts effects demonstrated that the NOB-PEG-PCL significantly inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells stimulated by RANKL. Furthermore, the NOB-PEG-PCL did not produce cytotoxicity on bone marrow-derived macrophages (BMMs). The mRNA expressions of genetic markers of osteoclasts including TRAP and cathepsin K were significantly decreased in the presence of NOB-PEG-PCL. In addition, the NOB-PEG-PCL inhibited OC differentiation of BMMs through RANKL-induced MAPK signal pathway. After administration of the NOB-PEG-PCL, NOB-PEG-PCL prevented bone loss and improved bone density in OVX mice. These findings suggest that NOB-PEG-PCL might have great potential in the treatment of osteoporosis. Conclusion: The results suggested that NOB-PEG-PCL micelles could effectively prevent NOB fast release from micelles and extend circulation time. The NOB-PEG-PCL delivery system may be a promising way to prevent and treat osteoporosis.


Assuntos
Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/etiologia , Flavonas/uso terapêutico , Micelas , Osteoclastos/patologia , Osteogênese , Ovariectomia/efeitos adversos , Animais , Morte Celular/efeitos dos fármacos , Citocinas/metabolismo , Liberação Controlada de Fármacos , Feminino , Flavonas/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Poliésteres/química , Polietilenoglicóis/química , Transdução de Sinais/efeitos dos fármacos
16.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 795-802, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31631628

RESUMO

Bone tissue engineering is considered as one of the most promising way to treat large segmental bone defect. When constructing bone tissue engineering graft in vitro, suitable bioreactor is usually used to incubate cell-scaffold complex under perfusion to obtain bone tissue engineering graft with good repair efficiency. However, the theoretical model for growth rate of single cell (especially for stem cell) during this process still has many defects. The difference between stem cells and terminally differentiated cells is always ignored. Based on our previous studies, this study used self-made perfusion apparatus to apply different modes and strengths of fluid shear stress (FSS) to the cells seeded on scaffolds. The effects of FSS on the proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) were investigated. The regression analysis model of the effect of FSS on the single-cell growth rate of MSCs was further established. The results showed that 0.022 5 Pa oscillatory shear stress had stronger ability to promote proliferation and osteogenic differentiation of MSCs, and the growth rate of a single MSC cell under FSS was modified. This study is expected to provide theoretical guidance for optimizing the perfusion culture condition of bone tissue engineering grafts in vitro.


Assuntos
Células-Tronco Mesenquimais , Diferenciação Celular , Modelos Teóricos , Osteogênese , Engenharia Tecidual , Tecidos Suporte
17.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 54(10): 662-669, 2019 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-31607001

RESUMO

Objective: To investigate the effect of microRNA-26a-5p on osteogenic differentiation of human periodontal ligament stem cells (hPDLSC) and its related mechanisms. Methods: hPDLSC in periodontal tissues from healthy adults and hPDLSC from periodontitis patients (PPDLSC) were isolated and cultured in vitro, respectively. The PPDLSC were divided into Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ groups. Group Ⅰ is control group, and the other four groups were transiently transfected with miR-NC, miR-26a-5p, antimiR-NC and antimiR-26a-5p lentiviral vectors, respectively. The osteogenic differentiation abilities of the cells in vitro were determined by alizarin red staining, alkaline phosphatase (ALP) activity assay and real-time quantitative PCR (qPCR). Totally 40 male mice (6-weeks) were equally divided into five groups with 8 mice in each group. The PPDLSCs cells (1×10(7)/ml) in Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ groups, which adhered to hydroxyapatine-tricalcium phosphate (HA-TCP), were implanted into the nude mice subcutaneously and the animal models were constructed to analyze the effect of miR-26a-5p on the osteogenic differentiation of PPDLSCs in vivo. PPDLSCs were divided into A, B, C, D groups, and transfected with miR-26a-5p+Wnt5a-Wt, miR-NC+Wnt5a-Wt, miR-26a-5p+Wnt5a-Mut and miR-NC+Wnt5a-Mut in each of the above mentioned 5 groups, respectively. The luciferase activity assay was used to detect the relative luciferase in A, B, C and D groups to analyze the targeting relationship between miR-26a-5p and Wnt5a. Osteogenic differentiation related proteins expression were analyzed by western blotting. Results: hPDLSC and PPDLSC were observed consistent with the characteristics of mesenchymal stem cells and had osteogenic differentiation ability in vitro. Compared with hPDLSC [(89.87±8.12)%], the osteogenic capacity of PPDLSC [(31.46±6.56)%] was significantly lower (P<0.05). The ALP activity (1.88±0.59), calcified nodules (79.88±5.92), the expression of the osteogenic differentiation markers Runt-related transcription factor 2 (Runx2) (2.40±0.70), ALP (2.10±0.60) and osteocalcin (3.00±0.90) mRNA in the PPDLSC from Group Ⅲ were significantly higher in comparison with the control group [(0.88±0.34), (29.69±2.65), (1.30±0.30), (0.09±0.25), (1.71±0.50)], while those from Group Ⅴ[(0.44±0.07), (14.83±3.05), (0.50±0.11), (0.30±0.08) and (0.80±0.17)] were significantly lower (P<0.05). In vivo studies in nude mice showed that the proportion of the osteogenic region [(34.96±5.65)%] in the miR-26a-5p group was significantly increased in comparison with the control group [(23.28±3.03)%], while in the antimiR-26a-5p group [(8.02±2.27)%] was significantly lower (P<0.05). The luciferase activity of the Group A (0.46±0.06) was significantly lower than Group B (3.46±0.45) (P<0.05). Compared with the control group, the expression levels of Wnt5a protein, calmodulin kinase Ⅱ and protein kinase C proteins in the Group Ⅲ were significantly decreased, while those in the GroupⅤ were significantly increased (P<0.05). Conclusions: MicroRNA-26a-5p could promote osteogenic differentiation of PPDLSC in vivo and in vitro, and its mechanism might be inhibiting the activation of Wnt/Ca(2+) signaling pathway by targeting Wnt5a.


Assuntos
MicroRNAs , Osteogênese , Ligamento Periodontal , Proteína Wnt-5a , Adulto , Animais , Diferenciação Celular , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/fisiologia , Ligamento Periodontal/metabolismo , Células-Tronco , Proteína Wnt-5a/metabolismo
18.
Int J Nanomedicine ; 14: 5831-5848, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534327

RESUMO

Purpose: In order to accelerate the tendon-bone healing processes and achieve the efficient osteointegration between the tendon graft and bone tunnel, we aim to design bioactive electrospun nanofiber membranes combined with tendon stem/progenitor cells (TSPCs) to promote osteogenic regeneration of the tendon and bone interface. Methods: In this study, nanofiber membranes of polycaprolactone (PCL), PCL/collagen I (COL-1) hybrid nanofiber membranes, poly(dopamine) (PDA)-coated PCL nanofiber membranes and PDA-coated PCL/COL-1 hybrid nanofiber membranes were successfully fabricated by electrospinning. The biochemical characteristics and nanofibrous morphology of the membranes, as well as the characterization of rat TSPCs, were defined in vitro. After co-culture with different types of electrospun nanofiber membranes in vitro, cell proliferation, viability, adhesion and osteogenic differentiation of TSPCs were evaluated at different time points. Results: Among all the membranes, the performance of the PCL/COL-1 (volume ratio: 2:1 v/v) group was superior in terms of its ability to support the adhesion, proliferation, and osteogenic differentiation of TSPCs. No benefit was found in this study to include PDA coating on cell adhesion, proliferation and osteogenic differentiation of TSPCs. Conclusion: The PCL/COL-1 hybrid electrospun nanofiber membranes are biocompatible, biomimetic, easily fabricated, and are capable of supporting cell adhesion, proliferation, and osteogenic differentiation of TSPCs. These bioactive electrospun nanofiber membranes may act as a suitable functional biomimetic scaffold in tendon-bone tissue engineering applications to enhance tendon-bone healing abilities.


Assuntos
Materiais Biocompatíveis/farmacologia , Osso e Ossos/fisiologia , Membranas Artificiais , Nanofibras/química , Células-Tronco/citologia , Tendões/citologia , Engenharia Tecidual/métodos , Animais , Osso e Ossos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Nanofibras/ultraestrutura , Osteogênese , Ratos Sprague-Dawley , Células-Tronco/efeitos dos fármacos
19.
Int J Nanomedicine ; 14: 6019-6033, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534334

RESUMO

Objective: Icariin (IC) promotes osteogenic differentiation, and it may be a potential small molecule drug for local application in bone regeneration. Icariin-loaded hydroxyapatite/alginate (IC/HAA) porous composite scaffolds were designed in this study for the potential application of the sustainable release of icariin and subsequent bone regeneration. Methods: An icariin-loaded hydroxyapatite/alginate porous composite scaffold was prepared and characterized by SEM and HPLC for morphology and release behavior, respectively. The mechanical properties, degradation in PBS and cytotoxicity on BMSCs were also evaluated by MTT assay, compression strength and calculation of weight remaining ratio, respectively. Rabbit BMSCs were cocultured with IC/HAA scaffolds, and ALP activity and Alizarin Red staining were performed to evaluate osteogenic differentiation induction. The mRNA and protein expression level of an osteogenic gene was detected by RT-PCR and Western blotting, respectively. In vivo animal models of critical bone defects in the radius of rabbit were used. Four and 12 weeks after the implantation of IC/HAA scaffolds in the bone defect, radiographic images of the radius were obtained and scored by using the Lane and Sandhu X-ray scoring system. Tissue samples were also evaluated using H&E and Masson staining, and an osteogenic gene and Wnt signaling pathway genes were detected. Results: A hydroxyapatite/alginate (HAA) porous composite scaffold-loaded icariin was fabricated using a freeze-drying method. Our data indicated that the icariin was loaded in alginate scaffold without compromising the macro/microstructure or mechanical properties of the scaffold. Notably, the IC/HAA promoted the proliferation of rBMSCs without exerting cytotoxicity on rBMSCs. In vivo, rabbit radius bone defect experiments demonstrated that the IC/HAA scaffold exhibited better capacity for bone regeneration than HAA, and IC/HAA upregulated the relative expression levels of an osteogenic gene and the Wnt signaling pathway genes. Most notably, the IC/HAA scaffold also inhibited osteoclast activity in vivo. Conclusion: Our data suggests a promising application for the use of HAA scaffolds to load icariin and promote bone regeneration in situ through mediation of the coupling processes of osteogenesis induction and osteoclast activity inhibition.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Flavonoides/farmacologia , Osteoclastos/metabolismo , Osteogênese , Tecidos Suporte/química , Alginatos/farmacologia , Animais , Materiais Biocompatíveis/farmacologia , Biomarcadores/metabolismo , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Durapatita/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Porosidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos , Rádio (Anatomia)/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
20.
Gene ; 720: 144096, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476405

RESUMO

Biologically active materials and polymeric materials used in tissue engineering have been one of the most attractive research areas in the past decades, especially the use of easily accessible materials from the patients that reduces or eliminates any patient's immune response. In this study, electrospun nanofibrous scaffolds were fabricated by using polyvinyl-alcohol (PVA), chitosan and hydroxyapatite (HA) polymers and platelet-rich plasma (PRP) as a bioactive substance isolated from human blood. Fabricated scaffold's structure and cytotoxicity were evaluated using scanning electron microscope and MTT assays. Scaffolds osteoinductivity was investigated by osteogenic differentiation of the mesenchymal stem cells (MSCs) at the in vitro level and then its osteoconductivity was examined by implanting at the critical-sized rat calvarial defect. The in vitro results showed that scaffolds have a good structure and good biocompatibility. Alkaline phosphatase activity, calcium content and gene expression assays were also demonstrated that their highest amount was detected in MSCs-seeded PVA-chitosan-HA(PRP) scaffold. For this reason, this scaffold alone and along with the MSCs was implanted to the animal defects. The in vivo results demonstrated that in the animals implanted with PVA-chitosan-HA(PRP), the defect was repaired to a good extent, but in those animals that received MSCs-seeded PVA-chitosan-HA(PRP), the defects was almost filled. It can be concluded that, PVA-chitosan-HA(PRP) alone or when stem cells cultured on them, has a great potential to use as an effective bone implant.


Assuntos
Diferenciação Celular , Nanofibras/química , Osteogênese , Plasma Rico em Plaquetas/química , Procedimentos Cirúrgicos Reconstrutivos , Crânio/cirurgia , Animais , Células Cultivadas , Quitosana/química , Durapatita/química , Masculino , Células-Tronco Mesenquimais/citologia , Álcool de Polivinil/química , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual , Tecidos Suporte
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