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1.
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
2.
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
3.
Braz Oral Res ; 33: e079, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31531565

RESUMO

Cell therapy associated with guided bone regeneration (GBR) can be used to treat bone defects under challenging conditions such as osteoporosis. This study aimed to evaluate the effect of mesenchymal stem cells (MSCs) in combination with a poly(vinylidene-trifluoroethylene)/barium titanate (PVDF-TrFE/BT) membrane on bone repair in osteoporotic rats. Osteoporosis was induced in female rats by bilateral removal of the ovaries (OVX) or sham surgery (SHAM), and the osteoporotic condition was characterized after 5 months by microtomographic and morphometric analyses. Calvarial defects were created in osteoporotic rats that immediately received the PVDF-TrFE/BT membrane. After 2 weeks, bone marrow-derived MSCs from healthy rats, characterized by the expression of surface markers using flow cytometry, or phosphate-buffered saline (PBS) (Control) were injected into the defects and bone formation was evaluated 4 weeks post-injection by microtomographic, morphometric, and histological analyses. A reduction in the amount of bone tissue in the femurs of OVX compared with SHAM rats confirmed the osteoporotic condition of the experimental model. More bone formation was observed when the defects were injected with MSCs compared to that with PBS. The modification that we are proposing in this study for the classical GBR approach where cells are locally injected after a membrane implantation may be a promising therapeutic strategy to increase bone formation under osteoporotic condition.


Assuntos
Compostos de Bário/farmacologia , Regeneração Tecidual Guiada/métodos , Células-Tronco Mesenquimais/fisiologia , Osteogênese/efeitos dos fármacos , Osteoporose/terapia , Polivinil/farmacologia , Titânio/farmacologia , Animais , Compostos de Bário/química , Densidade Óssea , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/fisiologia , Feminino , Citometria de Fluxo , Imagem Tridimensional , Células-Tronco Mesenquimais/química , Osteogênese/fisiologia , Osteoporose/fisiopatologia , Ovariectomia , Polivinil/química , Distribuição Aleatória , Ratos Wistar , Reprodutibilidade dos Testes , Fatores de Tempo , Titânio/química , Resultado do Tratamento
4.
J Anim Sci ; 97(8): 3369-3378, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31265734

RESUMO

The quality and strength of the skeleton is regulated by mechanical loading and adequate mineral intake of calcium (Ca) and phosphorus (P). Whole body vibration (WBV) has been shown to elicit adaptive responses in the skeleton, such as increased bone mass and strength. This experiment was designed to determine the effects of WBV and dietary Ca and P on bone microarchitecture and turnover. A total of 26 growing pigs were utilized in a 60-d experiment. Pigs were randomly assigned within group to a 2 × 2 factorial design with dietary Ca and P concentration (low and adequate) as well as WBV. The adequate diet was formulated to meet all nutritional needs according to the NRC recommendations for growing pigs. Low Ca, P diets had 0.16% lower Ca and 0.13% lower P than the adequate diet. Pigs receiving WBV were vibrated 30 min/d, 3 d/wk at a magnitude of 1 to 2 mm and a frequency of 50 Hz. On days 0, 30, and 60, digital radiographs were taken to determine bone mineral content by radiographic bone aluminum equivalency (RBAE) and serum was collected to measure biochemical markers of bone formation (osteocalcin, OC) and bone resorption (carboxy-terminal collagen crosslinks, CTX-I). At day 60, pigs were euthanized and the left third metacarpal bone was excised for detailed analysis by microcomputed tomography (microCT) to measure trabecular microarchitecture and cortical bone geometry. Maximum RBAE values for the medial or lateral cortices were not affected (P > 0.05) by WBV. Pigs fed adequate Ca and P tended (P = 0.10) to have increased RBAE max values for the medial and lateral cortices. WBV pigs had significantly decreased serum CTX-1 concentrations (P = 0.044), whereas animals fed a low Ca and P diet had increased (P < 0.05) OC concentrations. In bone, WBV pigs showed a significantly lower trabecular number (P = 0.002) and increased trabecular separation (P = 0.003), whereas cortical bone parameters were not significantly altered by WBV or diet (P > 0.05). In summary, this study confirmed the normal physiological responses of the skeleton to a low Ca, P diet. Interestingly, although the WBV protocol utilized in this study did not elicit any significant osteogenic response, decreases in CTX-1 in response to WBV may have been an early local adaptive bone response. We interpret these data to suggest that the frequency and amplitude of WBV was likely sufficient to elicit a bone remodeling response, but the duration of the study may not have captured the full extent of an entire bone remodeling cycle.


Assuntos
Cálcio na Dieta/farmacologia , Osteogênese/fisiologia , Fósforo na Dieta/farmacologia , Suínos/fisiologia , Animais , Densidade Óssea , Remodelação Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Cálcio na Dieta/metabolismo , Dieta/veterinária , Feminino , Masculino , Fósforo na Dieta/metabolismo , Distribuição Aleatória , Vibração , Microtomografia por Raio-X/veterinária
5.
Georgian Med News ; (290): 12-16, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31322506

RESUMO

Aim - study of marker enzymes, hormonal and carbohydrate-protein indicators of the state of reparative osteogenesis in patients with complicated and uncomplicated course of injuries of facial cranium. The study included 81 patients with injuries of facial cranium, which were divided into 2 groups, depending on the presence of complications. The following enzyme indicators were studied: the level of excretion of hydroxyproline in daily urine; alkaline and acid phosphatase activity; the percentage of bone isoenzymes of alkaline phosphatase. To assess the mineral metabolism, the level of total and ionized calcium and inorganic phosphorus in the blood serum, as well as their excretion in the urine, were determined. To assess the state of metabolism, the concentration of glycosaminoglycans and their fractions in the blood serum were studied. To study the structural and functional state of the bone tissue the densitometry was performed. In patients with complicated course of injuries of facial cranium assosiated with traumatic brain injury there was revealed the increase (р<0,05) of: excretion of phosphorus, uronic acids and oxyproline, while the excretion of calcium was not disturbed (р>0,05), and excretion of magnesium was decreased (р<0,05). It was found out that the level of calcium of blood serum in patients with complicated course is significantly (р<0,05) lower than in the control group and does not depend on the presence of craniocerebral injury (р>0,05). The decrease of the level of ionized calcium content in blood serum can be the confirmation of lower metabolic activity of reparative osteogenesis processes, first of all at the expense of damage of central mechanisms. When studying the content of carbohydrate-protein metabolites by complicated course of injuries of facial cranium, the absolute increase (р<0,05) of concentration of chondroitin-6-sulfates was revealed, and during the analysis of results it was found out that in absolute values, as well as in structural indexes, the specific weight of various fractions changes, that can be the evidence of instability of mechanisms of osteogenesis and of damage of physiological mechanisms of reparative osteogenesis. Densitometric equivalents of forming of complicated course of injuries of facial cranium are the increase of broadband ultrasonic attenuation and the decrease of its spreading speed on the background of low levels of chondroitin-6-sulfates.


Assuntos
Cálcio/sangue , Traumatismos Craniocerebrais , Traumatismos Faciais , Osteogênese/fisiologia , Fósforo/sangue , Crânio/lesões , Fosfatase Ácida/metabolismo , Fosfatase Alcalina/metabolismo , Cálcio/urina , Traumatismos Craniocerebrais/epidemiologia , Traumatismos Craniocerebrais/metabolismo , Traumatismos Faciais/enzimologia , Traumatismos Faciais/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Hidroxiprolina/urina , Minerais/metabolismo , Fósforo/urina
6.
BMC Oral Health ; 19(1): 133, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266498

RESUMO

BACKGROUND: Vital pulp therapy preserves and maintains the integrity and the health of dental pulp tissue that has been injured by trauma, caries or restorative procedures. The enhancement of cells viability and formation of reparative dentine and new blood vessels are vital determinants of the success of direct pulp capping. Therefore, the aims of this study was to evaluate and compare the in vitro osteogenic, odontogenic and angiogenic effects of mineral trioxide aggregate (MTA), calcium hydroxide [Ca(OH)2], Biodentine and Emdogain on dental pulp stem cells (DPSCs) and examine the effects of the tested materials on cell viability. METHODS: DPSCs were treated with MTA, Ca(OH)2, Biodentine or Emdogain. Untreated cells were used as control. The cell viability was measured by MTT assay on day 3. Real-Time PCR with SYBR green was used to quantify the gene expression levels of osteogenic markers (alkaline phosphatase and osteopontin), odontogenic marker (dentin sialophosphoprotein) and angiogenic factor (vascular endothelial growth factor) on day 7 and day 14. RESULTS: All capping materials showed variable cytotoxicity against DPSCs (77% for Emdogain, 53% for MTA, 26% for Biodentine and 16% for Ca(OH)2 compared to control (P value < 0.0001). Osteopontin (OPN) and dentin sialophosphoprotein (DSPP) gene expression was increased by all four materials. However, alkaline phosphatase (ALP) was upregulated by all materials except Emdogain. Vascular endothelial growth factor (VEGF) expression was upregulated by all four tested materials except Ca(OH)2. CONCLUSIONS: Our results suggest MTA, Biodentine and Emdogain exhibit similar attributes and may score better than Ca(OH)2. Emdogain could be a promising alternative to MTA and Biodentine in enhancing pulp repair capacity following dental pulp injury. However, further future research is required to assess the clinical outcomes and compare it with the in vitro findings.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Hidróxido de Cálcio , Proteínas do Esmalte Dentário , Polpa Dentária/fisiologia , Odontogênese/fisiologia , Osteogênese/fisiologia , Óxidos , Silicatos , Sobrevivência Celular , Combinação de Medicamentos , Células-Tronco , Fator A de Crescimento do Endotélio Vascular
7.
J Appl Oral Sci ; 27: e20180641, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31166414

RESUMO

OBJECTIVES: Infection, inflammation and bone resorption are closely related events in apical periodontitis development. Therefore, we sought to investigate the role of cyclooxygenase (COX) in osteoclastogenesis and bone metabolism signaling in periapical bone tissue after bacterial lipopolysaccharide (LPS) inoculation into root canals. METHODOLOGY: Seventy two C57BL/6 mice had the root canals of the first molars inoculated with a solution containing LPS from E. coli (1.0 mg/mL) and received selective (celecoxib) or non-selective (indomethacin) COX-2 inhibitor. After 7, 14, 21 and 28 days the animals were euthanized and the tissues removed for total RNA extraction. Evaluation of gene expression was performed by qRT-PCR. Statistical analysis was performed using analysis of variance (ANOVA) followed by post-tests (α=0.05). RESULTS: LPS induced expression of mRNA for COX-2 (Ptgs2) and PGE2 receptors (Ptger1, Ptger3 and Ptger4), indicating that cyclooxygenase is involved in periapical response to LPS. A signaling that favours bone resorption was observed because Tnfsf11 (RANKL), Vegfa, Ctsk, Mmp9, Cd36, Icam, Vcam1, Nfkb1 and Sox9 were upregulated in response to LPS. Indomethacin and celecoxib differentially modulated expression of osteoclastogenic and other bone metabolism genes: celecoxib downregulated Igf1r, Ctsk, Mmp9, Cd36, Icam1, Nfkb1, Smad3, Sox9, Csf3, Vcam1 and Itga3 whereas indomethacin inhibited Tgfbr1, Igf1r, Ctsk, Mmp9, Sox9, Cd36 and Icam1. CONCLUSIONS: We demonstrated that gene expression for COX-2 and PGE2 receptors was upregulated after LPS inoculation into the root canals. Additionally, early administration of indomethacin and celecoxib (NSAIDs) inhibited osteoclastogenic signaling. The relevance of the cyclooxygenase pathway in apical periodontitis was shown by a wide modulation in the expression of genes involved in both bone catabolism and anabolism.


Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Cavidade Pulpar/metabolismo , Lipopolissacarídeos/farmacologia , Osteogênese/fisiologia , Tecido Periapical/efeitos dos fármacos , Tecido Periapical/metabolismo , Prostaglandina-Endoperóxido Sintases/fisiologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Reabsorção Óssea/metabolismo , Celecoxib/farmacologia , Ciclo-Oxigenase 2/análise , Escherichia coli/metabolismo , Expressão Gênica , Indometacina/farmacologia , Lipopolissacarídeos/análise , Masculino , Camundongos Endogâmicos C57BL , Osteogênese/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/análise , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos , Receptores de Prostaglandina E/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Regulação para Cima
8.
J Anim Sci ; 97(8): 3300-3312, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31231753

RESUMO

Previous research has determined that maintaining young animals in stalls is detrimental to their bone health, while the addition of 50 to 82-m sprints 5 d/week aids in counteracting the reduction of bone strength from confinement. The current research aims to determine if 1 or 3 d/week of sprinting affords the same benefits to bone as 5 d/week of sprinting compared to animals confined with no sprinting. Twenty-four Holstein bull calves were obtained from the Michigan State University Dairy Cattle Teaching and Research Center. At 9 wk of age, calves were randomly assigned to treatments of 1, 3, or 5 d/week of sprint exercise, or to the confined control group sprinted 0 d/week. Each treatment had 6 calves. Individual sprinting bouts included a single sprint down a 71-m concrete aisle. For the duration of the 6-wk study, calves were housed at the MSU Beef Cattle Teaching and Research Center in stalls which afforded calves room to stand, lay down, and turn around. Serum was collected weekly via jugular venipuncture to obtain concentrations of osteocalcin (OC) and C-telopeptide crosslaps of type I collagen (CTX-1)-markers of bone formation and degradation, respectively. Sprints were videotaped weekly to determine stride frequency and sprint velocity. On day 42, calves were humanely euthanized at the Michigan State University Meat Lab and both front limbs were immediately harvested. Computed tomography scans and mechanical testing were performed on the left fused third and fourth metacarpal bones. Serum OC concentration was greatest for calves sprinted 5 d/week (P < 0.001). Calves sprinted 5 d/week had both greater stride frequency (P < 0.05) and lower sprint velocity (P < 0.05). All exercise treatments experienced greater dorsal cortical widths compared to control animals (P < 0.01). Through mechanical testing, fracture forces of all sprinting treatments were determined to be greater than the control treatment (P < 0.02). Results from this study support that sprinting 1, 3, or 5 d/week during growth can increase bone health and cause favorable alterations in bone markers. While all exercise treatments had over a 20% increase to fracture force, calves sprinted 1 d/week sprinted only 426 m over the 6-wk study and still experienced over a 20% increase in bone strength compared to confined calves. This study demonstrates the remarkably few strides at speed needed to enhance bone strength and emphasizes the danger to skeletal strength if sprinting opportunities are not afforded.


Assuntos
Cavalos/fisiologia , Animais , Biomarcadores/sangue , Reabsorção Óssea/fisiopatologia , Osso e Ossos/fisiologia , Bovinos , Colágeno Tipo I/sangue , Masculino , Osteocalcina/sangue , Osteogênese/fisiologia , Condicionamento Físico Animal , Distribuição Aleatória
9.
Molecules ; 24(9)2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31035627

RESUMO

Nowadays, regenerative medicine has paid special attention to research (in vitro and in vivo) related to bone regeneration, specifically in the treatment of bone fractures or skeletal defects, which is rising worldwide and is continually demanding new developments in the use of stem cells, growth factors, membranes and scaffolds based on novel nanomaterials, and their applications in patients by using advanced tools from molecular biology and tissue engineering. Strontium (Sr) is an element that has been investigated in recent years for its participation in the process of remodeling and bone formation. Based on these antecedents, this is a review about the Strontium Folate (SrFO), a recently developed non-protein based bone-promoting agent with interest in medical and pharmaceutical fields due to its improved features in comparison to current therapies for bone diseases.


Assuntos
Regeneração Óssea , Ácido Fólico/metabolismo , Estrôncio/metabolismo , Tecidos Suporte , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Polpa Dentária/citologia , Ácido Fólico/química , Humanos , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Estrôncio/química , Engenharia Tecidual , Tecidos Suporte/química , Vitamina B 12/química , Vitamina B 12/metabolismo , Vitamina B 6/química , Vitamina B 6/metabolismo
10.
Cell Prolif ; 52(4): e12623, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31115100

RESUMO

L-type voltage-gated calcium ion channels (L-VGCCs) have been demonstrated to be the mediator of several significant intracellular activities in excitable cells, such as neurons, chromaffin cells and myocytes. Recently, an increasing number of studies have investigated the function of L-VGCCs in non-excitable cells, particularly stem cells. However, there appear to be no systematic reviews of the relationship between L-VGCCs and stem cells, and filling this gap is prescient considering the contribution of L-VGCCs to the proliferation and differentiation of several types of stem cells. This review will discuss the possible involvement of L-VGCCs in stem cells, mainly focusing on osteogenesis mediated by mesenchymal stem cells (MSCs) from different tissues and neurogenesis mediated by neural stem/progenitor cells (NSCs). Additionally, advanced applications that use these channels as the target for tissue engineering, which may offer the hope of tissue regeneration in the future, will also be explored.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Cálcio/metabolismo , Células-Tronco/metabolismo , Animais , Sinalização do Cálcio/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Humanos , Osteogênese/fisiologia , Engenharia Tecidual/métodos
11.
Biomed Res Int ; 2019: 3241263, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31119163

RESUMO

Purpose: We studied osteogenesis and morphofunctional features of the anterior tibial muscle using 3-mm high-frequency automated lengthening with the Ilizarov apparatus alone and in combination with intramedullary nailing. Material and Methods: Tibia was lengthened with a round-the-clock automated distractor at a 3-mm daily rate for 10 days in 16 mongrel dogs. In group 1 (n = 8), a 1.8-mm intramedullary titanium wire coated with hydroxyapatite was introduced into the tibial canal followed by Ilizarov frame mounting and transverse osteotomy of the diaphysis. Distraction mode was 0.025 mm x 120 increments a day. In group 2 (n = 8), distraction mode was the same but nailing was not used. Bone formation and the anterior tibial muscle were studied at two time points: (1) upon distraction completion; (2) three months after the apparatus removal. Bone formation was studied radiographically. Muscle preparations were examined histologically and stereomicroscopically. Results: There was a threefold reduction in the distraction time in both groups. Consolidation took 13.83±4.02 days in group 1 and 33.7±2.4 days in group 2. Muscle macropreparations of the experimental limb in group 1 at study time points did not show significant differences from intact tissues. Muscle histostructure in both groups was characterized by activation of angiogenesis and myohistogenesis, but the volumetric density of microvessels in the lengthening phase was three times higher in group 1. Conclusion: Combined technology significantly reduces the total lengthening procedure and does not compromise limb functions. Intramedullary HA-coated wires promote faster bone formation. The muscle was able to exhibit structural adaptation and plasticity of a restitution type.


Assuntos
Fixação Intramedular de Fraturas/métodos , Técnica de Ilizarov , Músculo Esquelético/crescimento & desenvolvimento , Osteogênese/efeitos dos fármacos , Animais , Materiais Revestidos Biocompatíveis/uso terapêutico , Modelos Animais de Doenças , Cães , Durapatita/química , Fixação Interna de Fraturas/métodos , Humanos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Músculo Esquelético/cirurgia , Osteogênese/fisiologia , Tíbia/diagnóstico por imagem , Tíbia/fisiopatologia , Tíbia/cirurgia , Titânio/química , Titânio/uso terapêutico
12.
Biomed Pharmacother ; 114: 108803, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30951949

RESUMO

Physiological root resorption of deciduous teeth is a normal phenomenon, however, the potential mechanisms underlying this process remain unclear. This study aimed to investigate ability of stem cells from human exfoliated deciduous teeth (SHED) on promoting the osteoclastic differentiation of osteoclast precursors and clarify mechanisms underlying this process in vitro. SHED and dental pulp stem cells (DPSCs) were obtained from deciduous teeth and healthy permanent teeth. An indirect co-culture system of SHED or DPSCs were used. The osteoclast precursor peripheral blood mononuclear cells (PBMCs) were established. Ability of SHED and DPSCs in promoting osteoclastogenesis was determined using triiodothyronine receptor auxiliary protein (TRAP) staining, real-time real-time PCR (RT-PCR) and western blotting. The effect of inflammation on the pro-osteoclastogenesis ability of SHED was determined using enzyme linked immunosorbent assay (ELISA), RT-PCR and western blotting. The function of the nuclear factor-κB (NF-κB) pathway in promoting the osteoclastogenesis ability of SHED was determined using RT-PCR and western blotting. SHED exhibited an increased ability to promote osteoclastic differentiation. Expression of tumor necrosis factor-α (TNF-α) was significantly higher in SHED than in DPSCs. Expression of cathepsin K (CTSK), TRAP, and receptor-activator of nuclear-factor-κ B ligand (RANKL), RANKL/osteoprotegerin (OPG) ratio, and expression of cytoplasmic phosphorylated inhibitor of NF-κB α (p-IκBα) and nuclear p65 were markedly up-regulated in SHED post the TNF-α treatment but decreased following NF-κB inhibition. In conclusion, inflammatory cytokine TNF-α appeared to activate NF-κB pathway to up-regulate expression of NF-κB, enhancing ability of SHED in promoting osteoclastogenesis via regulating RANKL/OPG expression.


Assuntos
Osteogênese/fisiologia , Reabsorção da Raiz/metabolismo , Dente Decíduo/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Catepsina K/metabolismo , Diferenciação Celular/fisiologia , Criança , Técnicas de Cocultura/métodos , Citocinas/metabolismo , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Osteoclastos/metabolismo , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Células-Tronco/metabolismo , Adulto Jovem
13.
In Vitro Cell Dev Biol Anim ; 55(5): 387-394, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30993556

RESUMO

This study aimed at investigating the expression of osteoblast and chondrocyte-related genes in mesenchymal stem cells (MSCs), derived from rabbit adipose tissue, under mechanical vibration. The cells were placed securely on a vibrator's platform and subjected to 300 Hz of sinusoidal vibration, with a maximum amplitude of 10 µm, for 45 min per day, and for 14 consequent days, in the absence of biochemical reagents. The negative control group was placed in the conventional culture medium with no mechanical loading. The expression of osteoblast and chondrocyte-related genes was investigated using real-time polymerase chain reaction (real-time PCR). In addition, F-actin fiber structure and alignment with the help of actin filament fluorescence staining were evaluated, and the level of metabolic activity of MSCs was determined by the methyl thiazolyl tetrazolium assay. The real-time PCR study showed a significant increase of bone gene expression in differentiated cells, compared with MSCs (P < 0.05). On the other hand, the level of chondrocyte gene expression was not remarkable. Applying mechanical vibration enhanced F-actin fiber structure and made them aligned in a specific direction. It was also found that during the differentiation process, the metabolic activity of the cells increased (P < 0.05). The results of this work are in agreement with the well-accepted fact that the MSCs, in the absence of growth factors, are sensitive to low-amplitude, high-frequency vibration. Outcomes of this work can be applied in cell therapy and tissue engineering, when regulation of stem cells is required.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Mesenquimais/fisiologia , Estresse Mecânico , Vibração/uso terapêutico , Actinas/genética , Tecido Adiposo/metabolismo , Tecido Adiposo/fisiologia , Animais , Células da Medula Óssea/fisiologia , Diferenciação Celular/genética , Condrócitos/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Coelhos , Engenharia Tecidual
14.
Plast Reconstr Surg ; 143(5): 993e-1002e, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31033820

RESUMO

BACKGROUND: Cell-seeded biomaterial scaffolds have been proposed as a future option for reconstruction of bone tissue. The ability to generate larger, functional volumes of bone has been a challenge that may be addressed through the use of perfusion bioreactors. In this study, the authors investigated use of a tubular perfusion bioreactor system for the growth and differentiation of bone marrow stromal (mesenchymal stem) cells seeded onto fibrin, a highly angiogenic biomaterial. METHODS: Cells were encapsulated within fibrin beads and cultured either within a tubular perfusion bioreactor system or statically for up to 14 days. Scaffolds were analyzed for osteogenic differentiation. A rodent cranial defect model (8-mm diameter) was used to assess the bone regeneration of scaffolds cultured in the bioreactor, statically, or used immediately after formation. Immunohistochemistry was used to visualize CD31 vessel density. Micro-computed tomographic imaging was used to visualize mineral formation within the defect volume. RESULTS: Tubular perfusion bioreactor system-cultured samples showed significantly greater osteodifferentiation, indicated by an increase in VEGF expression and mineral deposition, compared with statically cultured samples. Increased expression of OPN, RUNX2, VEGF, and CD90 was seen over time in both culture methods. After implantation, bioreactor samples exhibited greater bone formation and vessel density compared with all other groups. Analysis of micro-computed tomographic images showed full union formation through the greatest diameter of the defect in all bioreactor samples and the highest levels of mineralized volume after 8 weeks. CONCLUSION: Mesenchymal stem cells encapsulated in fibrin beads and cultured in the tubular perfusion bioreactor system resulted in increased vascularization and mineralized tissue formation in vivo relative to static culture.


Assuntos
Regeneração Óssea , Técnicas de Cultura de Células/métodos , Osteogênese/fisiologia , Crânio/lesões , Tecidos Suporte , Animais , Reatores Biológicos , Células da Medula Óssea/fisiologia , Técnicas de Cultura de Células/instrumentação , Diferenciação Celular/fisiologia , Células Cultivadas , Traumatismos Craniocerebrais/cirurgia , Modelos Animais de Doenças , Humanos , Masculino , Células-Tronco Mesenquimais/fisiologia , Procedimentos Ortopédicos/instrumentação , Procedimentos Ortopédicos/métodos , Perfusão/métodos , Ratos , Ratos Sprague-Dawley , Procedimentos Cirúrgicos Reconstrutivos/instrumentação , Procedimentos Cirúrgicos Reconstrutivos/métodos , Crânio/cirurgia , Resultado do Tratamento
15.
J Appl Oral Sci ; 27: e20180103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30994771

RESUMO

OBJECTIVE: This study aimed to evaluate the inflammatory effect and bone formation in sterile surgical failures after implantation of a collagen sponge with mesenchymal stem cells from human dental pulp (hDPSCs) and Aloe vera. MATERIAL AND METHODS: Rattus norvegicus (n=75) were divided into five experimental groups according to treatment: G1) control (blood clot); G2) Hemospon®; G3) Hemospon® in a culture medium enriched with 8% Aloe vera; G4) Hemospon® in a culture medium containing hDPSCs and G5) Hemospon® in a culture medium enriched with 8% Aloe vera and hDPSCs. On days 7, 15 and 30, the animals were euthanized, and the tibia was dissected for histological, immunohistochemistry and immunofluorescence analyses. The results were analyzed using nonparametric Kruskal-Wallis test and Dunn's post-test. RESULTS: On days 7 and 15, the groups with Aloe vera had less average acute inflammatory infiltrate compared to the control group and the group with Hemospon® (p<0.05). No statistically significant difference was found between the groups regarding bone formation at the three experimental points in time. Osteopontin expression corroborated the intensity of bone formation. Fluorescence microscopy revealed positive labeling with Q-Tracker® in hDPSCs before transplantation and tissue repair. CONCLUSION: The results suggest that the combination of Hemospon®, Aloe vera and hDPSCs is a form of clinical treatment for the repair of non-critical bone defects that reduces the inflammatory cascade's effects.


Assuntos
Aloe/química , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/fisiologia , Polpa Dentária/citologia , Transplante de Células-Tronco Mesenquimais/métodos , Extratos Vegetais/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Colágeno/farmacologia , Citometria de Fluxo , Hemostáticos/farmacologia , Humanos , Imuno-Histoquímica , Masculino , Microscopia de Fluorescência , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Osteopontina/análise , Ratos , Reprodutibilidade dos Testes , Tíbia/efeitos dos fármacos , Tíbia/patologia , Tíbia/fisiologia , Fatores de Tempo , Resultado do Tratamento
16.
Nat Commun ; 10(1): 1589, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30962442

RESUMO

Transmembrane and coiled-coil domains 1 (TMCO1) is a recently identified Ca2+ leak channel in the endoplasmic reticulum. TMCO1 dysfunction in humans is associated with dysmorphism, mental retardation, glaucoma and the occurrence of cancer. Here we show an essential role of TMCO1 in osteogenesis mediated by local Ca2+/CaMKII signaling in osteoblasts. TMCO1 levels were significantly decreased in bone from both osteoporosis patients and bone-loss mouse models. Tmco1-/- mice exhibited loss of bone mass and altered microarchitecture characteristic of osteoporosis. In the absence of TMCO1, decreased HDAC4 phosphorylation resulted in nuclear enrichment of HADC4, which leads to deacetylation and degradation of RUNX2, the master regulator of osteogenesis. We further demonstrate that TMCO1-mediated Ca2+ leak provides local Ca2+ signals to activate the CaMKII-HDAC4-RUNX2 signaling axis. The establishment of TMCO1 as a pivotal player in osteogenesis uncovers a novel potential therapeutic target for ameliorating osteoporosis.


Assuntos
Canais de Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas de Membrana/metabolismo , Osteoblastos/metabolismo , Osteoporose/fisiopatologia , Idoso , Animais , Canais de Cálcio/genética , Sinalização do Cálcio , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Feminino , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Pessoa de Meia-Idade , Osteogênese/fisiologia , Osteoporose/metabolismo , Ovariectomia , Estabilidade Proteica , Transdução de Sinais
17.
J Mater Sci Mater Med ; 30(4): 47, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30980130

RESUMO

The objective of this study was to fabricate and characterize chitosan combined with different amounts of simvastatin-loaded nanoparticles and to investigate their potential for guided bone regeneration in vitro and in vivo. Different SIM-CSN formulations were combined into a chitosan scaffold (SIM-CSNs-S), and the morphology, simvastatin release profile, and effect on cell proliferation and differentiation were investigated. For in vivo experiments, ectopic osteogenesis and the critical-size cranial defect model in SD rats were chosen to evaluate bone regeneration potential. All three SIM-CSNs-S formulations had a porous structure and exhibited sustained simvastatin release. CSNs-S showed excellent degradation and biocompatibility characteristics. The 4 mg SIM-CSNs-S formulation stimulated higher BMSC ALP activity levels, demonstrated significantly earlier collagen enhancement, and led to faster bone regeneration than the other formulations. SIM-CSNs-S should have a significant effect on bone regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Quitosana/química , Regeneração Tecidual Guiada/métodos , Nanopartículas/química , Nanopartículas/metabolismo , Sinvastatina/farmacocinética , Tecidos Suporte/química , Animais , Osso e Ossos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Preparações de Ação Retardada , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Composição de Medicamentos , Masculino , Teste de Materiais , Microesferas , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Sinvastatina/administração & dosagem , Propriedades de Superfície , Engenharia Tecidual/métodos
18.
Mayo Clin Proc ; 94(4): 652-659, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30947832

RESUMO

The aim of this study was to characterize endothelial progenitor cells with osteoblastic phenotype (EPC-OCNs) and their role in individuals with varying degrees of aortic stenosis (AS). Peripheral blood mononuclear cells retrieved from blood samples of individuals with mild (n=40), moderate (n=35), or severe (n=103) AS from September 16, 2008, through March 30, 2015, were analyzed by flow cytometry for the EPC surface markers CD34, CD133, and kinase insert domain receptor (KDR) and the osteoblastic cell surface marker OCN. Levels of EPC-OCNs were correlated with AS severity and calcifications. Patients with severe AS had significantly elevated numbers of total circulating EPC-OCNs, including the EPC-OCN subtypes CD133+/OCN+, CD34+/CD133+/OCN+, and CD133+/KDR+/OCN+, compared with those with mild AS. Individuals with moderate AS also had significantly increased numbers of the circulating progenitor cell CD133+/OCN+ compared with patients with mild AS. There was a significant association between total circulating EPC-OCN levels and aortic valve (AV) calcification, AV mean gradient, and AV area measured by echocardiography. In summary, this study found the presence of circulating EPC-OCNs in patients with progressive AV stenosis. These findings might support the potential role for EPC-OCNs in the progression of AV stenosis and calcification.


Assuntos
Estenose da Valva Aórtica/sangue , Estenose da Valva Aórtica/diagnóstico , Osteoblastos/fisiologia , Células-Tronco/fisiologia , Adulto , Idoso , Biomarcadores/sangue , Circulação Sanguínea/fisiologia , Calcinose/sangue , Calcinose/diagnóstico , Feminino , Humanos , Leucócitos Mononucleares/fisiologia , Masculino , Pessoa de Meia-Idade , Osteogênese/fisiologia
19.
J Craniofac Surg ; 30(4): 1303-1307, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30817520

RESUMO

To study the influence of distraction osteogenesis (DO) on the maxillary growth as first-stage treatment of palatal defect. The uniform palate defect experimental animal models (21 miniature pigs) were established surgically. Then animals were randomly divided into negative control group (A, n = 6), conventional surgery group (B, n = 6), and distraction osteogenesis group (C, n = 9) respectively. The group A underwent none treatment as control group, the group B were undergoing a conventional defect repair surgery, and the group C were undergoing a distraction osteogenesis treatment. Cone beam computed tomography examination was performed monthly to analyze the growth of maxilla for 6 months. One pig of group C was randomly sacrificed at 2, 4, and 8 weeks after the completion of DO and the tissue of distraction gap was stained with hematoxylin-eosin and Masson staining. At the end of 6th months, all pigs were sacrificed and tissues of the surgical area were stained as previous described. The palate defect was repaired by the distraction osteogenesis with the successful bone formation on the distraction gap. Group A and group C kept a similar growth rate, but that of group B was relatively slow. Distraction osteogenesis is efficient and successful for closing the defect of palate and there is no significant disturbance on the subsequent growth of the maxilla.


Assuntos
Fissura Palatina/cirurgia , Maxila/crescimento & desenvolvimento , Osteogênese por Distração/métodos , Animais , Masculino , Maxila/cirurgia , Osteogênese/fisiologia , Distribuição Aleatória , Suínos , Porco Miniatura
20.
Vet Clin North Am Exot Anim Pract ; 22(2): 123-134, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30872001

RESUMO

Cartilage and bone are the main skeletal tissues in exotic vertebrates and are distinguished by their cells and the extracellular matrices they produce. Differences in cartilage and bone formation and growth exist among small mammals, birds, and reptiles. A basic knowledge of cartilage and bone formation, composition, and function in small mammals, birds, and reptiles commonly kept as pets, and the major differences observed among species, is necessary to correctly evaluate and treat cartilage and bone lesions in these groups of animals.


Assuntos
Animais Exóticos/fisiologia , Osso e Ossos/fisiologia , Cartilagem/fisiologia , Osteogênese/fisiologia , Animais , Aves/fisiologia , Mamíferos/fisiologia , Répteis/fisiologia
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