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1.
Braz. dent. sci ; 25(1): 1-9, 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1353788

ABSTRACT

Objective: The objective of this study was to evaluate in vitro the influence of the anodized surface of Ti35Nb7Zr alloy on the behavior of osteogenic cells, for future application in biomedical implants. Material and Methods: For the development of this research, samples of commercially pure titanium (TiCp) and samples of Ti35Nb7Zr alloy were anodized, both were characterized by scanning electron microscopy (SEM) and were plated afterwards with human osteoblast-like cells (MG63 line) (2 x 104). Cell adhesion, cytotoxicity test, formation of mineralization nodules and a comet assay were also performed in different periods. The bottom of the plate was used as a control, without a sample. Results: SEM analysis showed that the topography of both samples presented surfaces covered by nanotubes. Cellular morphology exhibited spreading in both samples proposing an intimate cell- material liaison. After 3 days, the Ti35Nb7Zr group exhibited greater cell viability than the TiCp group (p<0.01). Regarding calcium content, there was no statistical difference between the anodized groups, but there was a difference between the experimental groups and the control group (p<0.01). In the comet assay, the percentage of DNA in the comet tail did not exhibit any significant difference (p>0.05) among the groups in the evaluated periods. Conclusion: It was concluded that this process of anodization was efficient to form nanotubes, as well as promote a positive influence on the behavior of osteogenic cells without promoting cell damage. (AU)


Objetivo: O objetivo deste estudo foi avaliar in vitro a influência da superfície anodizada da liga Ti35Nb7Zr no comportamento de células osteogênicas, para futura aplicação em implantes biomédicos. Material e Métodos: Para o desenvolvimento desta pesquisa, amostras de titânio comercialmente puro (TiCp) e amostras da liga Ti35Nb7Zr foram anodizadas, ambas foram caracterizadas por microscopia eletrônica de varredura (MEV) e posteriormente plaqueadas com células semelhantes a osteoblastos humanos (linha MG63) (2 x 104). Foram realizados em diferentes períodos a adesão celular, teste de citotoxicidade, formação de nódulos de mineralização e ensaio do cometa. O fundo da placa foi usado como controle, sem amostra. Resultados: A análise em MEV mostrou que a topografia de ambas as amostras apresentava superfícies cobertas por nanotubos. A morfologia celular exibiu espalhamento em ambas as amostras, propondo uma ligação íntima célula-material. Após 3 dias, o grupo Ti35Nb7Zr exibiu maior viabilidade celular do que o grupo TiCp (p<0.01). Em relação ao teor de cálcio, não houve diferença estatística entre os grupos anodizados, mas houve diferença entre os grupos experimentais e o grupo controle (p<0.01). No ensaio do cometa, a porcentagem de DNA na cauda do cometa não apresentou diferença significativa (p> 0.05) entre os grupos nos períodos avaliados. Conclusão:Concluiu-se que esse processo de anodização foi eficiente para formar nanotubos, além de promover uma influência positiva no comportamento das células osteogênicas sem promover dano celular. (AU)


Subject(s)
Osteoblasts , Titanium
2.
Electron. j. biotechnol ; 52: 52-58, July. 2021. tab, ilus
Article in English | LILACS | ID: biblio-1283505

ABSTRACT

BACKGROUND: Osteoporosis attacks approximately 10% of the population worldwide. Sika Deer (Cervus nippon), one of China's precious traditional medicinal animals, has been widely recorded in ancient Chinese medical books and claimed for centuries to have numerous medical benefits including bone strengthening. This study aimed to find the use of Sika Deer bone in treating osteoporosis according to traditional records and to investigate the protective effect of Sika Deer bone polypeptide extract on glucocorticoidinduced osteoporosis (GIOP) in rats. RESULTS: Sika Deer bone polypeptide extract could increase serum Ca2+ and BGP, decrease serum P3+, ALP, PTH, and CT, but had no effect on serum NO in rats with GIOP. The immunohistochemical iNOS results of the rats' distal femur were negative in each group. Besides the model group, the eNOS color reaction in osteoblasts was strongly positive in the other three groups. CONCLUSIONS: Sika Deer bone polypeptide extract can improve pathological changes in the microstructure and stimulate the expression of eNOS in osteoblasts. The protective effect on bone might be mediated by eNOS-dependent NO generation.


Subject(s)
Animals , Male , Rats , Osteoporosis/prevention & control , Peptides/pharmacology , Bone and Bones/metabolism , Deer , Osteoblasts , Dexamethasone , Rats, Wistar , Nitric Oxide Synthase Type III/drug effects
3.
Braz. dent. sci ; 24(2): 1-9, 2021. ilus, tab
Article in English | LILACS, BBO | ID: biblio-1177505

ABSTRACT

Objective: To evaluate the effect of salbutamol, montelukast, and prednisone on orthodontic tooth movement in rats. Material and Methods: In vivo experimental preclinical study. The sample consisted of 48 rats randomly distributed in four study groups. Group A was given saline solution; to group B, salbutamol 4 mg/Kg; to group C, montelukast 2.5 mg/Kg and to group D, prednisone 2.5 mg/Kg. All were fitted with orthodontic devices and the medications were administered intraperitoneally every 12 hours for 5 days. The clinical evaluation (variation in the interincisal distance) was performed at one, three, five, and seven days and the histopathological analysis (cell count) at five and seven days. Results: In the clinical evaluation of the variation in the interincisal distance, a significant difference was found in all the evaluations (p <0.05). It was found that the salbutamol group presented higher variation values in the interincisal distance on all the days evaluated. In the histopathological analysis at five and seven days, it was found that the osteoblast and osteocyte count was significantly higher in the salbutamol group compared to the other groups (p <0.05). However, in the subgroup analysis, it was found that there was no significant difference in the osteoblast and osteocyte count between the prednisone, montelukast, and control group (p> 0.05). Conclusion: The administration of salbutamol increased the magnitude of orthodontic tooth movement; nonetheless, the administration of montelukast and prednisone did not modify the magnitude of orthodontic tooth movement in rats. (AU)


Objetivo: Avaliar o efeito do salbutamol, montelucaste e prednisona no movimento dentário ortodôntico em ratos. Material e métodos: Estudo pré-clínico experimental in vivo. A amostra foi composta por 48 ratos distribuídos aleatoriamente em quatro grupos de estudo. O grupo A recebeu solução salina; para o grupo B, salbutamol 4 mg/kg; ao grupo C, montelucaste 2,5 mg/kg e ao grupo D, prednisona 2,5 mg/kg. Todos foram equipados com dispositivos ortodônticos e os medicamentos foram administrados por via intraperitoneal a cada 12 horas por 5 dias. A avaliação clínica (variação da distância interincisal) foi realizada em um, três, cinco e sete dias e a análise histopatológica (contagem de células) em cinco e sete dias. Resultados: Na avaliação clínica da variação da distância interincisal, houve diferença significativa em todas as avaliações (p <0,05). Verificou-se que o grupo salbutamol apresentou maiores valores de variação na distância interincisal em todos os dias avaliados. Na análise histopatológica aos cinco e sete dias, verificou-se que a contagem de osteoblastos e osteócitos foi significativamente maior no grupo salbutamol em comparação aos demais grupos (p<0,05). No entanto, na análise de subgrupos, verificou-se que não houve diferença significativa na contagem de osteoblastos e osteócitos entre os grupos prednisona, montelucaste e controle (p>0,05). Conclusão: A administração de salbutamol aumentou a magnitude do movimento dentário ortodôntico; no entanto, a administração de montelucaste e prednisona não modificou a magnitude do movimento dos dentes ortodônticos em ratos. (AU)


Subject(s)
Animals , Rats , Osteoblasts , Osteocytes , Tooth Movement Techniques , Prednisone , Albuterol
4.
J. appl. oral sci ; 29: e20200870, 2021. tab, graf
Article in English | LILACS | ID: biblio-1250190

ABSTRACT

Abstract Bio-C Pulpecto (Bio-CP) was recently developed as the first bioceramic root filling material for primary teeth. Objective To evaluate the physicochemical properties of radiopacity, setting time, pH, cytocompatibility and potential of Bio-CP to induce mineralisation, compared with (1) Calen thickened with zinc oxide (Calen-ZO), and (2) zinc oxide and eugenol (ZOE). Methodology Physicochemical properties were evaluated according to ISO 6876. Saos-2 (human osteoblast-like cell line) exposed to extracts of the materials were subjected to assays of methyl thiazolyl tetrazolium, neutral red, alkaline phosphatase (ALP) activity and mineralised nodule production. The results were analysed using one-way or two-way ANOVA and Tukey's or Bonferroni's post-tests (α=0.05). Results All the materials showed radiopacity higher than 3 mm Al. Bio-CP had lower pH than Calen-ZO, but higher pH than ZOE. Calen-ZO and Bio-CP did not set. The setting time for ZOE was 110 min. The cytocompatibility order was Calen-ZO > Bio-CP > ZOE (1:2, 1:4 dilutions) and Calen-ZO > Bio-CP = ZOE (1:12, 1:24 dilutions) and Calen-ZO = Bio-CP > ZOE (1:32 dilution). Bio-CP induced greater ALP activity at 7 days, and greater mineralised nodule production, compared to Calen-ZO (p<0.05). Conclusions Bio-CP showed adequate physicochemical properties, cytocompatibility and potential to induce mineralisation.


Subject(s)
Humans , Root Canal Filling Materials , Dental Pulp Cavity , Osteoblasts , Root Canal Obturation , Tooth, Deciduous , Zinc Oxide-Eugenol Cement , Biology
5.
Article in Chinese | WPRIM | ID: wpr-879427

ABSTRACT

Osteoporosis is one of the common clinical orthopedic diseases, which can lead to a variety of complications. There are many pathogenic factors in this disease. The latest research found that ATP6V1H is a new gene leading to the occurrence of osteoporosis, and it is likely to become a new target for the future drug treatment of osteoporosis.This paper introduces the biological structure and characteristics of H subunit, summed up the human body caused by loss of ATP6V1H and animal models such as zebrafish, mice bone loss and osteoporosis symptom such as related research reports of the loss, from osteoclast, osteoblast and marrow stromal cell level and the connection between the various subunits further expounds the H subunit regulate bone dynamic balance of mechanism, to explore ATP6V1H in bone developmentand bone related diseases has laid a solid foundation, also provide new ideas for clinical treatment of osteoporosis.


Subject(s)
Animals , Bone and Bones , Mice , Osteoblasts , Osteoclasts , Osteoporosis/genetics , Zebrafish
6.
Article in English | WPRIM | ID: wpr-921366

ABSTRACT

The maintenance of bone homeostasis is critical for bone health. It is vulnerable to cause bone loss, even severely osteoporosis when the balance between bone formation and absorption is interrupted. Growing evidence has shown that energy metabolism disorders, such as abnormal glucose metabolism, irregular amino acid metabolism, and aberrant lipid metabolism, can damage bone homeostasis, causing or exacerbating bone mass loss and osteoporosis-related fractures. Here, we summarize the studies of energy metabolism in osteoblasts and osteoclasts and provide a better appreciation of how energy metabolism, especially glucose metabolism maintains bone homeostasis. With this knowledge, new avenues will be unraveled to understand and cue bone-related diseases such as osteoporosis.


Subject(s)
Bone and Bones , Energy Metabolism , Osteoblasts , Osteoclasts , Osteogenesis
7.
Article in English | WPRIM | ID: wpr-888697

ABSTRACT

Nowadays, orthodontic treatment has become increasingly popular. However, the biological mechanisms of orthodontic tooth movement (OTM) have not been fully elucidated. We were aiming to summarize the evidences regarding the mechanisms of OTM. Firstly, we introduced the research models as a basis for further discussion of mechanisms. Secondly, we proposed a new hypothesis regarding the primary roles of periodontal ligament cells (PDLCs) and osteocytes involved in OTM mechanisms and summarized the biomechanical and biological responses of the periodontium in OTM through four steps, basically in OTM temporal sequences, as follows: (1) Extracellular mechanobiology of periodontium: biological, mechanical, and material changes of acellular components in periodontium under orthodontic forces were introduced. (2) Cell strain: the sensing, transduction, and regulation of mechanical stimuli in PDLCs and osteocytes. (3) Cell activation and differentiation: the activation and differentiation mechanisms of osteoblast and osteoclast, the force-induced sterile inflammation, and the communication networks consisting of sensors and effectors. (4) Tissue remodeling: the remodeling of bone and periodontal ligament (PDL) in the compression side and tension side responding to mechanical stimuli and root resorption. Lastly, we talked about the clinical implications of the updated OTM mechanisms, regarding optimal orthodontic force (OOF), acceleration of OTM, and prevention of root resorption.


Subject(s)
Humans , Osteoblasts , Osteoclasts , Periodontal Ligament , Periodontium , Root Resorption , Tooth Movement Techniques
8.
Article in Chinese | WPRIM | ID: wpr-888119

ABSTRACT

The present study aimed to explore the effect of Erxian Decoction on proteomics of osteoblasts stimulated by hydrogen peroxide(H_2O_2) and its protective mechanism with the H_2O_2-induced cell model of oxidative stress. The primary osteoblasts were cultured from the skulls of newborn rats(within 24 hours) and divided into a control group, a model group, a Fosamax group, and an Erxian Decoction group. Blank serum was added in the control group and model group, and the drug-containing serum was added correspondingly to the remaining two groups. After 45 hours, H_2O_(2 )stimulation was conducted for three hours except for the control group, followed by protein extraction. Nano-LC-LTQ-Orbitrap system was used for protein detection, Protein Discovery for protein identification, and SIEVE for quantitative and qualitative analysis. Furthermore, following the blocking of PI3 K signaling pathway by LY294002(10 μmol·L~(-1)), a control group, a model group, an LY294002 group, an Erxian Decoction group, and an Erxian Decoction + LY294002 group were set up to observe the effect of Erxian Decoction on cell proliferation, alkaline phosphatase(ALP) activity, and the relative expression of BMP-2, OPG, p-Akt, p-FoxO1 of osteoblasts stimulated by H_2O_2 under LY294002 intervention. The results revealed that 78 differential proteins were discovered between the Erxian Decoction group and model group, which were involved in the regulation of PI3 K/Akt, glucagon, estrogen, insulin, and other signaling pathways. LY294002 blunted the promoting effect of Erxian Decoction on osteoblast proliferation and significantly down-regulated the expression of OPG and p-FoxO1, whereas its down-regulation on the expression of BMP-2 and p-Akt was not significant. Both LY294002 and Erxian Decoction increased the ALP activity of osteoblasts, which may be related to the cell state and the cell differentiation. The above results suggest that Erxian Decoction can protect osteoblasts stimulated by H_2O_2, with the PI3 K/Akt signaling pathway as one of the internal mechanisms.


Subject(s)
Animals , Drugs, Chinese Herbal , Hydrogen Peroxide , Osteoblasts/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proteomics , Proto-Oncogene Proteins c-akt/metabolism , Rats , Signal Transduction
9.
Article in Chinese | WPRIM | ID: wpr-888005

ABSTRACT

Cannabinoid receptor type 2( CB2 R),a member of the G protein-coupled receptor( GPCR) superfamily,has a variety of biological activities,such as regulating pain response,resisting inflammation and fibrosis,and mediating bone metabolism. Some CB2 R regulators exhibit a good regulatory effect on bone metabolism. Cannabinoids in Cannabis sativa can cause psychoactive effects despite various pharmacological actions they exerted by targeting CB2 R. Therefore,it is of great significance to discover CB2 R regulators in non-Cannabis plants for finding new lead compounds without psychoactive effects and elucidating the action mechanism of plant drugs. The present study clarifies the discovery,structure,and physiological functions of CB2 R,especially its regulatory effects on bone metabolism,summarized CB2 R regulators extracted from non-Cannabis plants,and systematically analyzes the regulatory effects of CB2 R regulators on bone metabolism in animals,osteoblasts,and osteoclasts,to provide a scientific basis for the discovery of new CB2 R regulators and the development of anti-osteoporotic drugs.


Subject(s)
Animals , Cannabinoids/pharmacology , Cannabis , Osteoblasts , Osteoclasts , Receptors, Cannabinoid
10.
Article in English | WPRIM | ID: wpr-880869

ABSTRACT

Gap junction (GJ) has been indicated to have an intimate correlation with adhesion junction. However, the direct interaction between them partially remains elusive. In the current study, we aimed to elucidate the role of N-cadherin, one of the core components in adhesion junction, in mediating connexin 43, one of the functional constituents in gap junction, via transforming growth factor-β1(TGF-β1) induction in osteoblasts. We first elucidated the expressions of N-cadherin induced by TGF-β1 and also confirmed the upregulation of Cx43, and the enhancement of functional gap junctional intercellular communication (GJIC) triggered by TGF-β1 in both primary osteoblasts and MC3T3 cell line. Colocalization analysis and Co-IP experimentation showed that N-cadherin interacts with Cx43 at the site of cell-cell contact. Knockdown of N-cadherin by siRNA interference decreased the Cx43 expression and abolished the promoting effect of TGF-β1 on Cx43. Functional GJICs in living primary osteoblasts and MC3T3 cell line were also reduced. TGF-β1-induced increase in N-cadherin and Cx43 was via Smad3 activation, whereas knockdown of Smad3 signaling by using siRNA decreased the expressions of both N-cadherin and Cx43. Overall, these data indicate the direct interactions between N-cadherin and Cx43, and reveal the intervention of adhesion junction in functional gap junction in living osteoblasts.


Subject(s)
Cadherins , Cell Communication , Connexin 43 , Osteoblasts , Transforming Growth Factor beta1
11.
Article in Chinese | WPRIM | ID: wpr-880824

ABSTRACT

OBJECTIVE@#To investigate the regulatory role of long non-coding RNA Kcnq1ot1 in osteoclast differentiation, osteogenic differentiation and osteoporosis.@*METHODS@#The expression of lnc-Kcnq1ot1, Bglap, Runx2, Alp, Bsp, Nfatc1, Mmp9, Ctsk and Oscar were detected by real-time quantitative PCR (qRT-PCR) in the femoral bones from mouse models of postmenopausal osteoporosis (ovariectomized mice, @*RESULTS@#The expression of lnc-Kcnq1ot1 was significantly upregulated during osteoblast differentiation but downregulated in the bone tissues of osteoporotic mice and during osteoclast differentiation (@*CONCLUSIONS@#Our data demonstrate that lnc-Kcnq1ot1 promotes osteogenic differentiation and alleviates osteoclast differentiation, suggesting the potential of lnc-Kcnq1ot1 as a therapeutic target against osteoporosis.


Subject(s)
Animals , Cell Differentiation , Cells, Cultured , Mice , Osteoblasts , Osteoclasts , Osteogenesis
12.
Article in English | WPRIM | ID: wpr-880667

ABSTRACT

OBJECTIVES@#Excessive production of AGEs in diabetic patients will affect the normal function of osteoblasts, and this process may be related to autophagy of osteoblasts. This study aims to explore the effect of advanced glycation end products (AGEs) on autophagic activity during osteogenic differentiation in rat bone marrow mesenchymal stem cells (BMSCs).@*METHODS@#BMSCs were isolated and cultured in vitro, treated with different concentrations (0, 50, 100, 200, and 400 mg/L) of AGEs for different time (3, 6, 12, 24, 48, and 72 h). The proliferation activity was detected by CCK-8 method. The mRNA and protein expression levels of Beclin1 and LC3 in cells were detected by real-time PCR and Western blotting, respectively.The autophagic vacuoles were observed under the transmission electron microscope. The cells were treated with autophagy promoter rapamycin or autophagy inhibitor 3MA. After 7 days of osteogenic induction, we performed alkaline phosphatase (ALP) staining and real-time PCR to detect the mRNA expression levels of osteogenesis-related genes.@*RESULTS@#In the low-concentration groups, the proliferation activity in BMSCs was increased (@*CONCLUSIONS@#Low concentration of AGEs can enhance the proliferative activity of BMSCs and promote osteogenic differentiation by accelerating autophagy. High concentration of AGEs can suppress the proliferation of BMSCs and inhibit osteogenic differentiation by reducing autophagy.


Subject(s)
Animals , Autophagy , Bone Marrow Cells , Cell Differentiation , Cells, Cultured , Glycation End Products, Advanced/pharmacology , Humans , Osteoblasts , Osteogenesis , Rats , Rats, Sprague-Dawley
13.
Braz. dent. j ; 31(6): 617-622, Nov.-Dec. 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1132349

ABSTRACT

Abstract Recent studies suggest that osteoporosis, in addition to the damage caused in long bones, may cause deterioration in the jaws, especially in alveolar bone sites, with effects in the progress of periodontal disease as well as in bone healing. The aim of this study was to evaluate the effect of osteoporosis in the metabolism of rat alveolar bone osteoblasts. There were used 10 female rats divided in two experimental groups (Sham and OVX), which were ovariectomized and after 8 weeks euthanized to collect mandibular bone samples in order to isolate osteoblastic cells. The cells were cultured in 24-well plates to perform the in vitro experiments. After 7, 10 and 14 days, there were evaluated cell proliferation by MTT assay, in situ detection of alkaline phosphatase (ALP) as well as mineralized nodules and expression of genes associated to bone remodeling. Results showed that at 7, 10 and 14 days cell proliferation was lower for OVX group. In situ detection of ALP was higher at 7 days and lower at 10 and 14 days in OVX group. At 17 and 21 days, OVX group had a significative decrease of mineralization nodules. There was a downregulation in the expression of Alp, Bglap and Runx2 genes and an upregulation of Opg in OVX group, whereas Opn and Rankl modulation was similar between the evaluated groups. Our results suggest that osteoporosis has a deleterious effect on alveolar bone cells from ovariectomized rats, which might affect the treatment of diseases associated to the jaw bones.


Resumo Estudos recentes sugerem que a osteoporose, além dos danos provocados em ossos longos, pode causar deterioração dos ossos maxilares, especialmente na região do osso alveolar, com efeitos na progressão da doença periodontal assim como no reparo ósseo. O objetivo deste estudo foi avaliar o efeito da osteoporose no metabolismo de osteoblastos do osso alveolar mandibular de ratos. Foram utilizadas 10 ratas fêmeas divididas em dois grupos experimentais (Sham e OVX), que foram ovariectomizadas e após 8 semanas, eutanasiadas para coletar amostras do osso mandibular e isolar as células osteoblásticas. As células foram cultivadas em placas de cultura de 24 poços para serem realizados os experimentos in vitro. Após 7, 10 e 14 dias foram avaliados a proliferação celular pelo ensaio de MTT, detecção in situ de fosfatase alcalina (ALP) assim como de nódulos mineralizados e expressão quantitativa de genes associados à remodelação óssea. Os resultados mostraram que aos 7, 10 e 14 dias a proliferação celular foi menor para o grupo OVX. A detecção in situ de ALP foi maior aos 7 dias e menor aos 10 e 14 dias no grupo OVX. Aos 17 e 21 dias o grupo OVX apresentou uma diminuição dos nódulos mineralizados. Houve uma repressão na expressão dos genes Alp, Bglap e Runx2 e uma indução do gene Opg no grupo OVX, enquanto que a modulação dos genes Opn e Rankl foi similar entre os grupos experimentais. Nossos resultados sugerem que a osteoporose tem um efeito deletério no metabolismo de células do osso alveolar em ratas ovariectomizadas, o que pode afetar o tratamento de doenças associadas aos ossos maxilares


Subject(s)
Humans , Animals , Female , Rats , Osteoporosis/genetics , Osteoblasts , Bone and Bones , Ovariectomy , Bone Density , Alkaline Phosphatase
15.
Actual. osteol ; 16(2): [132]-[140], mayo.-ago. 2020. ilus
Article in Spanish | LILACS | ID: biblio-1129806

ABSTRACT

La oxitocina (OXT) como la arginina-vasopresina (AVP) son dos hormonas primitivas secretadas por la hipófisis posterior. Sus receptores están mucho más ampliamente distribuidos en el organismo de lo que se pensaba originalmente, incluido el hueso. En los estudios preclínicos, la OXT ha mostrado ser anabólica para el hueso, promoviendo la osteogénesis sobre la adipogénesis y favoreciendo la actividad osteoblástica sobre la osteoclástica. Tanto los osteoblastos como los osteoclastos tienen receptores para la OXT, y los efectos de los estrógenos sobre la masa ósea en ratones está mediada por lo menos en parte por la OXT. El mecanismo preciso por el cual la activación de los receptores de oxitocina (OXTR) se traduce en un incremento de la formación ósea permanece poco claro. La AVP también podría afectar el esqueleto en forma directa. Dos de los receptores de la AVP, V1a y V2 están expresados en osteoblastos y osteoclastos. La inyección de AVP en ratones de tipo salvaje aumenta la formación osteoclastos que producen resorción y reduce los osteoblastos formadores de hueso. En forma opuesta, la exposición de precursores osteoblásticos a antagonistas de los receptores V1a o V2, incrementan la osteoblastogénesis, como también lo hace la deleción genética del receptor V1a. (AU)


Both oxytocin (OXT) and argininevasopressin (AVP) are primitive hormones secreted by the posterior pituitary gland. OXT receptors are much more widely distributed in the body than originally thought, including in bone. In preclinical studies, OXT has been shown to be anabolic for bone, promoting osteogenesis over adipogenesis and favoring osteoblastic over osteoclastic activity. Both osteoblasts and osteoclasts have receptors for OXT, and the effects of estrogen on bone mass in mice is mediated at least in part by OXT. The precise mechanism by which the activation of oxytocin receptors (OXTRs) results in an increase in bone formation remains unclear. AVP could also have direct actions on the skeleton. The two AVP receptors, V1a and V2, are expressed in osteoblasts and osteoclasts. Injection of AVP in wild-type mice increases the formation of osteoclasts increasing bone resorption, and reduces bone-forming osteoblasts. On the contrary, the exposure of osteoblastic precursors to V1a and V2 antagonists increase osteoblastogenesis, the same as the genetic deletion of the V1a receptor. (AU)


Subject(s)
Humans , Animals , Mice , Pituitary Hormones, Posterior/biosynthesis , Arginine Vasopressin/adverse effects , Oxytocin/therapeutic use , Osteoblasts/physiology , Osteoclasts/physiology , Osteogenesis , Osteoporosis/therapy , Pituitary Hormones, Posterior/physiology , Arginine Vasopressin/antagonists & inhibitors , Arginine Vasopressin/biosynthesis , Arginine Vasopressin/physiology , Arginine Vasopressin/therapeutic use , Oxytocin/biosynthesis , Oxytocin/adverse effects , Oxytocin/physiology , Signal Transduction , Bone Density , Bone Density/drug effects , Receptors, Oxytocin/biosynthesis , Receptors, Oxytocin/physiology , Estradiol/therapeutic use , Estrogens/physiology
16.
Braz. dent. j ; 31(3): 304-309, May-June 2020. graf
Article in English | LILACS, BBO | ID: biblio-1132294

ABSTRACT

Abstract Among other factors, types of bisphosphonates and treatment regimens seem to be strongly associated with the success or failure of installation of osseointegrated implants. This study investigated the influence of two bisphosphonates, sodium alendronate (SA) and zoledronic acid (ZA), on the metabolism of osteoblasts. Human osteoblasts (Saos-2) were seeded onto machined or acid-treated titanium discs previously placed on 24-well plates in complete culture medium. After 24 h, cells were exposed to bisphosphonates at 0.5, 1 or 5 µM for 24 h, 48 h or 7 days. The effects of SA and ZA on osteoblasts were assessed based on the adhesion of these cells to the titanium surfaces by direct fluorescence, cell viability, total protein and collagen synthesis. Alkaline phosphatase activity and mineral nodule deposition by these cells were also evaluated. Data were evaluated by ANOVA and Tukey tests (α=0.05). Decreased adhesion of cells to the titanium discs was observed when exposed to both bisphosphonates; however, this lack of cell adhesion was more evident for ZA-treated cells. In addition, the exposure of osteoblasts to ZA decreased the viability, ALP activity and mineral nodule deposition, which may be related to poor osseointegration after implant installation.


Resumo Entre outros fatores, os tipos de bisfosfonatos bem como os regimes de tratamento parecem estar diretamente associados com o sucesso ou falhas na instalação de implantes osseointegrados. Este estudo avaliou a influência de dois bisfosfonatos, o alendronato de sódio (AS) e o ácido zoledrônico (AZ), no metabolismo de osteoblastos. Osteoblastos humanos (Saos-2) foram cultivados sobre discos de titânio polidos ou submetidos a tratamento ácido superficial, previamente alocados em placas de 24 compartimentos, utilizando meio de cultura completo. Após 24 horas, as células foram expostas aos bisfosfonatos, nas concentrações de 0,5, 1 ou 5 µM, por 24 h, 48 h, ou 7 dias. Os efeitos do AZ e AZ sobre os osteoblastos foram determinados considerando a adesão destas células às superfícies de titânio, por meio de fluorescência direta, a viabilidade celular, produção de proteína total e síntese de colágeno. A atividade de fosfatase alcalina e a deposição de nódulos mineralizados também foram avaliadas. Os dados foram analisados por meio do teste ANOVA complementado por Tukey (α = 0.05). Menor adesão dos osteoblastos foi observada quando estas células foram expostas a ambos os bisfosfonatos, porém, esta falha na adesão foi mais evidente para as células tratadas com AZ. Além disso, a exposição dos osteoblastos ao AZ também resultou em diminuição da viabilidade, atividade de ALP e deposição de nódulos mineralizados, o que pode estar relacionado a uma pobre osseointegração após a instalação do implante.


Subject(s)
Humans , Titanium , Diphosphonates , Osteoblasts , Surface Properties , Cell Adhesion , Cell Differentiation , Cells, Cultured , Cell Proliferation , Alkaline Phosphatase , Zoledronic Acid
17.
J. appl. oral sci ; 28: e20190156, 2020. graf
Article in English | LILACS, BBO | ID: biblio-1090765

ABSTRACT

Abstract Objective The present study aimed to investigate the participation of focal adhesion kinases (FAK) in interactions between osteoblastic cells and titanium (Ti) surfaces with three different topographies, namely, untreated (US), microstructured (MS), and nanostructured (NS). Methodology Osteoblasts harvested from the calvarial bones of 3-day-old rats were cultured on US, MS and NS discs in the presence of PF-573228 (FAK inhibitor) to evaluate osteoblastic differentiation. After 24 h, we evaluated osteoblast morphology and vinculin expression, and on day 10, the following parameters: gene expression of osteoblastic markers and integrin signaling components, FAK protein expression and alkaline phosphatase (ALP) activity. A smooth surface, porosities at the microscale level, and nanocavities were observed in US, MS, and NS, respectively. Results FAK inhibition decreased the number of filopodia in cells grown on US and MS compared with that in NS. FAK inhibition decreased the gene expression of Alp, bone sialoprotein, osteocalcin, and ALP activity in cells grown on all evaluated surfaces. FAK inhibition did not affect the gene expression of Fak, integrin alpha 1 ( Itga1 ) and integrin beta 1 ( Itgb1 ) in cells grown on MS, increased the gene expression of Fak in cells grown on NS, and increased the gene expression of Itga1 and Itgb1 in cells grown on US and NS. Moreover, FAK protein expression decreased in cells cultured on US but increased in cells cultured on MS and NS after FAK inhibition; no difference in the expression of vinculin was observed among cells grown on all surfaces. Conclusions Our data demonstrate the relevance of FAK in the interactions between osteoblastic cells and Ti surfaces regardless of surface topography. Nanotopography positively regulated FAK expression and integrin signaling pathway components during osteoblast differentiation. In this context, the development of Ti surfaces with the ability to upregulate FAK activity could positively impact the process of implant osseointegration.


Subject(s)
Animals , Osteoblasts/drug effects , Sulfones/pharmacology , Titanium/chemistry , Quinolones/pharmacology , Focal Adhesion Protein-Tyrosine Kinases/antagonists & inhibitors , Osteoblasts/physiology , Sulfones/chemistry , Surface Properties , Microscopy, Electron, Scanning , Signal Transduction , Gene Expression , Integrins/analysis , Cell Differentiation/drug effects , Cells, Cultured , Osseointegration/drug effects , Rats, Wistar , Quinolones/chemistry , Cell Proliferation/drug effects , Focal Adhesion Protein-Tyrosine Kinases/analysis , Focal Adhesion Protein-Tyrosine Kinases/chemistry , Real-Time Polymerase Chain Reaction
18.
Article in English | WPRIM | ID: wpr-785339

ABSTRACT

PURPOSE: Osteitis refers to the development of new bone formation and remodeling of bone in chronic rhinosinusitis (CRS) patients; it is typically associated with eosinophilia, nasal polyps (NPs), and recalcitrant CRS. However, the roles of ossification in CRS with or without NPs remain unclear due to the lack of appropriate animal models. Thus, it is necessary to have a suitable animal model for greater advances in the understanding of CRS pathogenesis.METHODS: BALB/c mice were administered ovalbumin (OVA) and staphylococcal enterotoxin B (SEB). The numbers of osteoclasts and osteoblasts and bony changes were assessed. Micro computed tomography (micro-CT) scans were conducted to measure bone thickness. Immunofluorescence, immunohistochemistry, and quantitative polymerase chain reaction were performed to evaluate runt-related transcription factor 2 (RUNX2), osteonectin, interleukin (IL)-13, and RUNX2 downstream gene expression. Gene set enrichment analysis was performed in mucosal tissues from control and CRS patients. The effect of resveratrol was evaluated in terms of osteogenesis in a murine eosinophilic CRS NP model.RESULTS: The histopathologic changes showed markedly thickened bones with significant increase in osteoblast numbers in OVA/SEB-treated mice compared to the phosphate-buffered saline-treated mice. The structural changes in bone on micro-CT were consistent with the histopathological features. The expression of RUNX2 and IL-13 was increased by the administration of OVA/SEB and showed a positive correlation. RUNX2 expression mainly co-localized with osteoblasts. Bioinformatic analysis using human CRS transcriptome revealed that IL-13-induced bony changes via RUNX2. Treatment with resveratrol, a candidate drug against osteitis, diminished the expression of IL-13 and RUNX2, and the number of osteoblasts in OVA/SEB-treated mice.CONCLUSIONS: In the present study, we found the histopathological and radiographic evidence of osteogenesis using a previously established murine eosinophilic CRS NP model. This animal model could provide new insights into the pathophysiology of neo-osteogenesis and provide a basis for developing new therapeutics.


Subject(s)
Animals , Computational Biology , Core Binding Factor Alpha 1 Subunit , Enterotoxins , Eosinophilia , Eosinophils , Fluorescent Antibody Technique , Gene Expression , Humans , Immunohistochemistry , Interleukin-13 , Interleukins , Mice , Models, Animal , Mucous Membrane , Nasal Polyps , Nose , Osteitis , Osteoblasts , Osteoclasts , Osteogenesis , Osteonectin , Ovalbumin , Polymerase Chain Reaction , Sinusitis , Transcription Factors , Transcriptome
19.
Article in Chinese | WPRIM | ID: wpr-879370

ABSTRACT

OBJECTIVE@#To analyze the role of endoplasmic reticulum stress response in the development of osteoblast apoptosis and osteolysis in osteolytic bone tissue, and to explore the causes of artificial joint loosening, so as to provide new ideas and theoretical basis for the prevention and treatment of artificial joint loosening.@*METHODS@#The animal model of osteolysis induced by wear particles was established by mouse skull, and randomly divided into 4 groups, 7 rats in each group:group 1, blank control group;group 2, wear particles tial6v4 nano alloy powder (TiNPs) group;group 3, endoplasmic reticulum stress response positive control (TiNPs+Tg) group; group 4, endoplasmic reticulum stress response inhibitor (TiNPs+4-PBA) group. The pathological changes of osteolysis were observed by toluidine blue staining, HE staining and ALP staining;the expression of endoplasmic reticulum stress response marker protein was detected by Western Blotting;the apoptosis of osteoblasts in osteolytic skull tissue was detected by TUNEL and Caspase-3 immunohistochemistry.@*RESULTS@#Wear particles TiNPs can induce osteolysis in vitro, aggravate the infiltration of inflammatory cells and inhibit the differentiation and maturation of osteoblasts. At the same time, wear particles can also up regulate the markers of endoplasmic reticulum stress response and promote the apoptosis of osteoblasts in osteolytic bone tissue. After adding 4-PBA, an inhibitor of endoplasmic reticulum stress (4-PBA), on the basis of wear particles TiNPs, the symptoms of osteolysis were significantly relieved, bone erosion and inflammatory infiltration were significantly reduced, the differentiation and maturation of osteoblasts were improved, the number of apoptotic osteoblasts decreased sharply, and the expression of endoplasmic reticulum stress marker protein gradually decreased.@*CONCLUSION@#Endoplasmic reticulum stress is involved in the formation of osteolysis and plays an important role in the occurrence and development of osteolysis. At the same time, endoplasmic reticulum stress can be used as a new therapeutic target to provide new ideas and methods for clinical reversal or treatment of osteolysis and aseptic loosening.


Subject(s)
Animals , Apoptosis , Cell Differentiation , Endoplasmic Reticulum Stress , Mice , Osteoblasts , Osteolysis/chemically induced , Rats
20.
Braz. j. med. biol. res ; 53(11): e9798, 2020. graf
Article in English | ColecionaSUS, LILACS, ColecionaSUS | ID: biblio-1132489

ABSTRACT

Osteoblast differentiation is an effective way to promote bone formation. Long non-coding RNA taurine upregulated 1 (TUG1) has been identified as a crucial modulator of multiple biological processes. This study was designed to investigate the function of TUG1 in the proliferation and differentiation of osteoblast precursor cells hFOB1.19. In this study, we found that TUG1 promoted hFOB1.19 cell proliferation, while TUG1 knockdown hindered cell proliferation. TUG1 and cannabinoid receptor 2 (CNR2) were upregulated, while miR-545-3p was down-regulated in hFOB1.19 cells undergoing osteoblastic differentiation. TUG1 induced osteoblast differentiation by increasing alkaline phosphatase (ALP) activity and the expression of osteoblastic differentiation markers. TUG1 was a sponge of miR-545-3p and regulated osteoblastic differentiation by modulating miR-545-3p. Moreover, miR-545-3p directly targeted CNR2 and restored the effect of CNR2 on osteoblastic differentiation. In conclusion, TUG1 accelerated the proliferation and differentiation of osteoblasts by sponging miR-545-3p and increasing CNR2 expression, which might provide a new biomarker for bone diseases.


Subject(s)
Humans , RNA, Long Noncoding/genetics , Osteoblasts , Taurine , Cell Differentiation , MicroRNAs , Receptor, Cannabinoid, CB2 , Cell Proliferation
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