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1.
PLoS One ; 15(8): e0238132, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853221

RESUMO

Bears do not suffer from osteoporosis during hibernation, which is associated with long-term inactivity, lack of food intake, and cold exposure. However, the mechanisms involved in bone loss prevention have scarcely been elucidated in bears. We investigated the effect of serum from hibernating Japanese black bears (Ursus thibetanus japonicus) on differentiation of peripheral blood mononuclear cells (PBMCs) to osteoclasts (OCs). PBMCs collected from 3 bears were separately cultured with 10% serum of 4 active and 4 hibernating bears (each individual serum type was assessed separately by a bear PBMCs), and differentiation were induced by treatment with macrophage colony stimulating factor (M-CSF) and receptor activator of NF-kB ligand (RANKL). PBMCs that were cultured with the active bear serum containing medium (ABSM) differentiated to multi-nucleated OCs, and were positive for TRAP stain. However, cells supplemented with hibernating bear serum containing medium (HBSM) failed to form OCs, and showed significantly lower TRAP stain (p < 0.001). On the other hand, HBSM induced proliferation of adipose derived mesenchymal stem cells (ADSCs) similarly to ABSM (p > 0.05), indicating no difference on cell growth. It was revealed that osteoclastogenesis of PBMCs is hindered by HBSM, implying an underlying mechanism for the suppressed bone resorption during hibernation in bears. In addition, this study for the first time showed the formation of bears' OCs in-vitro.


Assuntos
Hibernação/fisiologia , Osteoclastos/fisiologia , Osteogênese/fisiologia , Ursidae/fisiologia , Animais , Reabsorção Óssea/metabolismo , Reabsorção Óssea/fisiopatologia , Diferenciação Celular/fisiologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/fisiologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Osteoclastos/metabolismo , Osteoporose/metabolismo , Osteoporose/fisiopatologia , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Ursidae/metabolismo
2.
Life Sci ; 257: 118033, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32621924

RESUMO

The present study aimed to investigate the effects of phosphatidylserine liposomes (PSLs) and phosphatidylserine liposomes containing alendronate (AL-PSLs) on the improvement of methylprednisolone (MP) induced osteoporosis in a rat model. AL-PSLs formulation was prepared, characterized, and evaluated in different pH media to simulate gastrointestinal condition. Osteoporosis was induced by 3 weeks oral administration of MP (10 mg/kg) and then treatment by PSLs, AL-PSLs, and alendronate (AL). Bone metabolic and biomechanical markers were measured in treated rat groups. Also, Tartrate-resistant acid phosphatase (TRAP) staining and histomorphometry were evaluated on bone tissues of treated rats. AL-PSLs were obtained in a size range of 155 nm and negatively surface charge with an entrapment efficiency of 42%. The AL leakage from AL-PSLs did not exhibit a significant difference in acidic or basic media in comparison with the neutral condition. The concentrations of calcium, osteocalcin, bone alkaline phosphatase, and osteoprotegerin (OPG) of serum were significantly increased in PSLs and AL-PSLs treated groups compared to the MP group. Also, PSLs and AL-PSLs significantly improved the thickness and volume of the cortical and trabecular bone mass in treated groups. In addition, TRAP staining indicated a significant decrease of osteoclast number in osteoporotic rats treated with AL-PSLs and PSLs. In this study, AL-PSLs and even PSLs alone made a potential bone mechanical strength in glucocorticoid-induced bone loss more than AL in rats. In conclusion, our findings suggest that PSLs consumption with or without an anti-osteoporotic drug might be an applicable choice in control of osteoporosis.


Assuntos
Alendronato/farmacologia , Osteoporose/tratamento farmacológico , Fosfatidilserinas/farmacologia , Animais , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/farmacologia , Osso e Ossos/metabolismo , Modelos Animais de Doenças , Fêmur/efeitos dos fármacos , Lipossomos/farmacologia , Masculino , Metilprednisolona/farmacologia , Osteocalcina/metabolismo , Osteoclastos/metabolismo , Osteoporose/metabolismo , Fosfatidilserinas/metabolismo , Ratos , Ratos Wistar
3.
Proc Natl Acad Sci U S A ; 117(29): 17187-17194, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32636266

RESUMO

Osteoprotegerin (OPG), a secreted decoy receptor for receptor activator of nuclear factor B ligand (RANKL), plays an essential role in regulating bone resorption. While much is known about the function of the N-terminal domains of OPG, which is responsible for binding to RANKL, the exact biological functions of the three C-terminal domains of OPG remain uncertain. We have previously shown that one likely function of the C-terminal domains of OPG is to bind cell surface heparan sulfate (HS), but the in vivo evidence was lacking. To investigate the biological significance of OPG-HS interaction in bone remodeling, we created OPG knock-in mice (opg AAA ). The mutated OPG is incapable of binding to HS but binds RANKL normally. Surprisingly, opg AAA/AAA mice displayed a severe osteoporotic phenotype that is very similar to opg-null mice, suggesting that the antiresorption activity of OPG requires HS. Mechanistically, we propose that the HS immobilizes secreted OPG at the surface of osteoblasts lineage cells, which facilitates binding of OPG to membrane-anchored RANKL. To further support this model, we altered the structure of osteoblast HS genetically to make it incapable of binding to OPG. Interestingly, osteocalcin-Cre;Hs2st f/f mice also displayed osteoporotic phenotype with similar severity to opg AAA/AAA mice. Combined, our data provide strong genetic evidence that OPG-HS interaction is indispensable for normal bone homeostasis.


Assuntos
Conservadores da Densidade Óssea/metabolismo , Conservadores da Densidade Óssea/farmacologia , Heparitina Sulfato/metabolismo , Osteoprotegerina/metabolismo , Osteoprotegerina/farmacologia , Animais , Sítios de Ligação , Reabsorção Óssea/metabolismo , Reabsorção Óssea/patologia , Osso e Ossos/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Osteoporose/genética , Osteoporose/metabolismo , Osteoporose/patologia , Osteoprotegerina/genética , Ligante RANK/metabolismo , Transcriptoma
4.
Proc Natl Acad Sci U S A ; 117(32): 19276-19286, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32719141

RESUMO

Bone homeostasis requires continuous remodeling of bone matrix to maintain structural integrity. This involves extensive communication between bone-forming osteoblasts and bone-resorbing osteoclasts to orchestrate balanced progenitor cell recruitment and activation. Only a few mediators controlling progenitor activation are known to date and have been targeted for intervention of bone disorders such as osteoporosis. To identify druggable pathways, we generated a medaka (Oryzias latipes) osteoporosis model, where inducible expression of receptor-activator of nuclear factor kappa-Β ligand (Rankl) leads to ectopic formation of osteoclasts and excessive bone resorption, which can be assessed by live imaging. Here we show that upon Rankl induction, osteoblast progenitors up-regulate expression of the chemokine ligand Cxcl9l. Ectopic expression of Cxcl9l recruits mpeg1-positive macrophages to bone matrix and triggers their differentiation into osteoclasts. We also demonstrate that the chemokine receptor Cxcr3.2 is expressed in a distinct subset of macrophages in the aorta-gonad-mesonephros (AGM). Live imaging revealed that upon Rankl induction, Cxcr3.2-positive macrophages get activated, migrate to bone matrix, and differentiate into osteoclasts. Importantly, mutations in cxcr3.2 prevent macrophage recruitment and osteoclast differentiation. Furthermore, Cxcr3.2 inhibition by the chemical antagonists AMG487 and NBI-74330 also reduced osteoclast recruitment and protected bone integrity against osteoporotic insult. Our data identify a mechanism for progenitor recruitment to bone resorption sites and Cxcl9l and Cxcr3.2 as potential druggable regulators of bone homeostasis and osteoporosis.


Assuntos
Matriz Óssea/metabolismo , Quimiocina CXCL9/metabolismo , Proteínas de Peixes/metabolismo , Oryzias/metabolismo , Osteoclastos/metabolismo , Osteoporose/metabolismo , Receptores CXCR3/metabolismo , Células-Tronco/metabolismo , Animais , Matriz Óssea/crescimento & desenvolvimento , Diferenciação Celular , Quimiocina CXCL9/genética , Modelos Animais de Doenças , Proteínas de Peixes/genética , Humanos , Macrófagos/metabolismo , Oryzias/genética , Oryzias/crescimento & desenvolvimento , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoclastos/citologia , Osteoporose/genética , Osteoporose/fisiopatologia , Ligação Proteica , Receptores CXCR3/genética , Células-Tronco/citologia
6.
Cell Prolif ; 53(6): e12834, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32468637

RESUMO

OBJECTIVES: Advanced glycation end products (AGEs) are considered a cause of diabetic osteoporosis. Although adipose-derived stem cells (ASCs) are widely used in the research of bone regeneration, the mechanisms of the osteogenic differentiation of ASCs from diabetic osteoporosis model remain unclear. This work aimed to investigate the influence and the molecular mechanisms of AGEs on the osteogenic potential of ASCs. MATERIALS AND METHODS: Enzyme-linked immunosorbent assay was used to measure the change of AGEs in diabetic osteoporotic and control C57BL/6 mice. ASCs were obtained from the inguinal fat of C57BL/6 mice. AGEs, 5-aza2'-deoxycytidine (5-aza-dC) and DKK-1 were used to treat ASCs. Real-time cell analysis and cell counting kit-8 were used to monitor the proliferation of ASCs within and without AGEs. Real-time PCR, Western blot and Immunofluorescence were used to analyse the genes and proteins expression of osteogenic factors, DNA methylation factors and Wnt/ß-catenin signalling pathway among the different groups. RESULTS: The AGEs and DNA methylation were increased in the adipose and bone tissue of the diabetic osteoporosis group. Untreated ASCs had higher cell proliferation activity than AGEs-treatment group. The expression levels of osteogenic genes, Opn and Runx2, were lower, and mineralized nodules were less in AGEs-treatment group. Meanwhile, DNA methylation was increased, and the Wnt signalling pathway markers, including ß-Catenin, Lef1 and P-GSK-3ß, were inhibited. After treatment with 5-aza-dC, the osteogenic differentiation capacity of ASCs in the AGEs environment was restored and the Wnt signalling pathway was activated during this process. CONCLUSIONS: Advanced glycation end products inhibit the osteogenic differentiation ability of ASCs by activating DNA methylation and inhibiting Wnt/ß-catenin pathway in vitro. Therefore, DNA methylation may be promising targets for the bone regeneration of ASCs with diabetic osteoporosis.


Assuntos
Tecido Adiposo/citologia , Metilação de DNA , Complicações do Diabetes/metabolismo , Produtos Finais de Glicação Avançada/farmacologia , Osteogênese/efeitos dos fármacos , Osteoporose/metabolismo , Células-Tronco/metabolismo , Tecido Adiposo/metabolismo , Animais , Osso e Ossos/metabolismo , Proliferação de Células , Células Cultivadas , Decitabina/farmacologia , Complicações do Diabetes/patologia , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Camundongos Endogâmicos C57BL , Osteoporose/patologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Via de Sinalização Wnt
7.
Metabolism ; 108: 154250, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32335074

RESUMO

BACKGROUND: Chronic steroid treatment causes an increase in visceral adiposity and osteoporosis. It is believed that steroids may alter a balance between differentiation of mesenchymal stem cells (MSCs) into either adipocytes or osteoblasts; however, the detailed molecular mechanisms are unclear. We previously identified Dexras1 as a critical factor that potentiates adipogenesis in response to glucocorticoids. Thus, in this study, we investigated the role of Dexras1 in maintaining the balance between chronic steroid treatment-associated adipogenesis and osteoporosis. MATERIAL AND METHODS: We treated wild type (WT) and Dexras1 knockout (KO) mice with dexamethasone for five weeks followed by 60% HFD for additional two weeks with dexamethasone. The changes of glucocorticoid-induced body weight gain and osteoporosis were analyzed. Bone marrow derived stromal cells (BMSCs) and mouse embryonic fibroblasts (MEFs) extracted from WT and Dexras1 KO mice, as well as MC3T3-E1 pre-osteoblasts and osteoclasts differentiated from RAW264.7 were analyzed to further define the role of Dexras1 in osteoblasts and osteoclasts. RESULTS: Dual-energy X-ray absorptiometry and micro-computed tomography analyses in murine femurs revealed that Dexras1 deficiency was associated with increased osteogenesis, concurrent with reduced adipogenesis. Furthermore, Dexras1 deficiency promoted osteogenesis of BMSCs and MEFs in vitro, suggesting that Dexras1 deficiency prevents steroid-induced osteoporosis. We also observed that Dexras1 downregulated SMAD signaling pathways, which reduced the osteogenic differentiation capacity of pre-osteoblast MC3T3-E1 cells into mature osteoblasts. CONCLUSION: We propose that Dexras1 is critical for maintaining the equilibrium between adipogenesis and osteogenesis upon steroid treatment.


Assuntos
Adipogenia/fisiologia , Osteogênese/fisiologia , Proteínas ras/metabolismo , Células 3T3 , Adipócitos/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Fêmur/metabolismo , Glucocorticoides/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/metabolismo , Células RAW 264.7 , Transdução de Sinais/fisiologia
9.
Cell Prolif ; 53(4): e12789, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32157750

RESUMO

OBJECTIVES: Oestrogen is known to inhibit osteoclastogenesis, and numerous studies have identified it as an autophagic activator. To date, the role of oestrogen in the autophagy of osteoclast precursors (OCPs) during osteoclastogenesis remains unclear. This study aimed to determine the effect of autophagy regulated by the biologically active form of oestrogen (17ß-estradiol) on osteoclastogenesis. MATERIALS AND METHODS: After treatment with 17ß-estradiol in OCPs (from bone marrow-derived macrophages, BMMs) and ovariectomy (OVX) mice, we measured the effect of 17ß-estradiol on the autophagy of OCPs in vitro and in vivo. In addition, we studied the role of autophagy in the OCP proliferation, osteoclast differentiation and bone loss regulated by 17ß-estradiol using autophagic inhibitor or knock-down of autophagic genes. RESULTS: The results showed that direct administration of 17ß-estradiol enhanced the autophagic response of OCPs. Interestingly, 17ß-estradiol inhibited the stimulatory effect of receptor activator of nuclear factor-κB ligand (RANKL) on the autophagy and osteoclastogenesis of OCPs. Moreover, 17ß-estradiol inhibited the downstream signalling of RANKL. Autophagic suppression by pharmacological inhibitors or gene silencing enhanced the inhibitory effect of 17ß-estradiol on osteoclastogenesis. In vivo assays showed that the autophagic inhibitor 3-MA not only inhibited the autophagic activity of the OCPs in the trabecular bone of OVX mice but also enhanced the ability of 17ß-estradiol to ameliorate bone loss. CONCLUSIONS: In conclusion, our study showed that oestrogen directly enhanced the autophagy of OCPs, which inhibited its anti-osteoclastogenic effect. Drugs based on autophagic inhibition may enhance the efficacy of oestrogen on osteoporosis.


Assuntos
Autofagia/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Células Cultivadas , Estradiol/uso terapêutico , Estrogênios/uso terapêutico , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Ligante RANK/metabolismo
10.
Cell Mol Life Sci ; 77(17): 3293-3309, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32130428

RESUMO

Metallomics is a rapidly evolving field of bio-metal research that integrates techniques and perspectives from other "-omics" sciences (e.g. genomics, proteomics) and from research vocations further afield. Perhaps the most esoteric of this latter category has been the recent coupling of biomedicine with element and isotope geochemistry, commonly referred to as isotope metallomics. Over the course of less than two decades, isotope metallomics has produced numerous benchmark studies highlighting the use of stable metal isotope distribution in developing disease diagnostics-e.g. cancer, neurodegeneration, osteoporosis-as well as their utility in deciphering the underlying mechanisms of such diseases. These pioneering works indicate an enormous wealth of potential and provide a call to action for researchers to combine and leverage expertise and resources to create a clear and meaningful path forward. Doing so with efficacy and impact will require not only building on existing research, but also broadening collaborative networks, bolstering and deepening cross-disciplinary channels, and establishing unified and realizable objectives. The aim of this review is to briefly summarize the field and its underpinnings, provide a directory of the state of the art, outline the most encouraging paths forward, including their limitations, outlook and speculative upcoming breakthroughs, and finally to offer a vision of how to cultivate isotope metallomics for an impactful future.


Assuntos
Metais/metabolismo , Pesquisa Biomédica , Cromatografia por Troca Iônica , Humanos , Marcação por Isótopo , Espectrometria de Massas , Metais/análise , Neoplasias/metabolismo , Neoplasias/patologia , Osteoporose/metabolismo , Osteoporose/patologia
11.
Cell Mol Life Sci ; 77(18): 3525-3546, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32062751

RESUMO

Over the last three decades, the scaffold proteins prohibitins-1 and -2 (PHB1/2) have emerged as key signaling proteins regulating a myriad of signaling pathways in health and diseases. Small molecules targeting PHBs display promising effects against cancers, osteoporosis, inflammatory, cardiac and neurodegenerative diseases. This review provides an updated overview of the various classes of PHB ligands, with an emphasis on their mechanism of action and therapeutic potential. We also describe how these ligands have been used to explore PHB signaling in different physiological and pathological settings.


Assuntos
Cardiopatias/patologia , Ligantes , Neoplasias/terapia , Doenças do Sistema Nervoso/terapia , Osteoporose/terapia , Proteínas Repressoras/metabolismo , Expressão Gênica , Cardiopatias/metabolismo , Cardiopatias/terapia , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/patologia , Osteoporose/metabolismo , Osteoporose/patologia , Processamento de Proteína Pós-Traducional , Proteínas Repressoras/química , Proteínas Repressoras/genética , Transdução de Sinais
12.
J Endocrinol ; 245(1): 141-153, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32045363

RESUMO

Emerging evidence has indicated that estrogen deficiency contributes to osteoporosis by affecting the level of inflammation. The inflammation microenvironment affects many cellular physiological processes, one of which may be cellular senescence according to previous studies. Senescent cells cannot function normally and secrete inflammatory cytokines and degradative proteins, which are referred to as senescence-associated secretory phenotype (SASP) factors, inducing further senescence and inflammation. Thus, stopping this vicious cycle may be helpful for postmenopausal osteoporosis treatment. Here, we used ovariectomized (OVX) mice as an estrogen-deficient model and confirmed that OVX bone marrow mesenchymal stem cells (BMSCs) displayed a senescent phenotype and upregulated SASP factor secretion both in vitro and in vivo. Furthermore, JAK2/STAT3, an important cytokine secretion-related signalling pathway that is associated with SASP secretion, was activated. Estrogen addition and estrogen receptor blockade confirmed that the JAK2/STAT3 axis participated in OVX BMSC senescence by mediating SASP factors. And JAK inhibition reduced SASP factor expression, alleviated senescence and enhanced osteogenic differentiation. Intraperitoneal injection of a JAK inhibitor, ruxolitinib, prevented bone loss in OVX mice. Collectively, our results revealed that JAK2/STAT3 plays an important role in the inflammation-senescence-SASP feedback loop in OVX BMSCs and that JAK inhibition could be a new method for treating postmenopausal osteoporosis.


Assuntos
Células da Medula Óssea/metabolismo , Senescência Celular/fisiologia , Janus Quinase 2/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Células da Medula Óssea/citologia , Estrogênios/deficiência , Feminino , Humanos , Inflamação/metabolismo , Inflamação/fisiopatologia , Células-Tronco Mesenquimais/citologia , Camundongos , Osteoporose/metabolismo , Osteoporose/fisiopatologia , Ovariectomia , Transdução de Sinais/fisiologia
13.
Biochem Biophys Res Commun ; 524(4): 890-894, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32057362

RESUMO

Osteoporosis is a disease of low bone mass that places individuals at enhanced risk for fracture, disability, and death. Osteoporosis rates are expected to rise significantly in the coming decades yet there are limited pharmacological treatment options, particularly for long-term management of this chronic condition. The drug development pipeline is relatively bereft of new strategies, causing an urgent and unmet need for developing new strategies and targets for treating osteoporosis. Here, we examine a lesser-studied bone remodeling pathway, Neuromedin U (NMU), which is expressed in the bone microenvironment along with its cognate receptors NMU receptor 1 (NMUR1) and 2 (NMUR2). We independently corroborate a prior report that global loss of NMU expression leads to high bone mass and test the hypothesis that NMU negatively regulates osteoblast differentiation. Consistent with this, in vitro studies reveal NMU represses osteoblastic differentiation of osteogenic precursors but, in contrast, promotes osteoblastic marker expression, proliferation and activity of osteoblast-like cells. Phospho-profiling arrays were used to detail differential signaling outcomes that may underlie the opposite responses of these cell types. Collectively, our findings indicate that NMU exerts cell-type-specific responses to regulate osteoblast differentiation and activity.


Assuntos
Neuropeptídeos/genética , Osteoblastos/metabolismo , Osteoporose/genética , Fosfoproteínas/genética , Receptores Acoplados a Proteínas-G/genética , Receptores de Neuropeptídeos/genética , Receptores de Neurotransmissores/genética , Animais , Densidade Óssea , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Diferenciação Celular , Linhagem Celular , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Knockout , Neuropeptídeos/metabolismo , Osteoblastos/patologia , Osteogênese/genética , Osteoporose/metabolismo , Osteoporose/patologia , Fosfoproteínas/classificação , Fosfoproteínas/metabolismo , Fosforilação , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Receptores de Neurotransmissores/metabolismo , Transdução de Sinais
14.
Life Sci ; 246: 117422, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32057903

RESUMO

AIMS: This study aimed to investigate the effects of resveratrol (3, 4', 5-trihydroxystilbene, RES) on osteoporosis and the role of SIRT1/FoxO1 pathway in the process. MAIN METHODS: In vivo, mice were divided into 3 groups, Sham, ovariectomized (OVX) and OVX-RES group. Micro-CT, histology and histomorphometry were conducted to detect details of bone mass and microstructure. The expression of osteoblast markers was tested by Real-time qPCR and serum markers which reflected bone formation and resorption were analyzed by enzyme-linked immunosorbent assay (ELISA). Besides, we assayed sirtuin 1 (SIRT1) expression and the concentration of serum superoxide dismutase (SOD). In vitro, osteoblasts were seperated into 3 groups: control, H2O2 (hydrogen peroxide, H2O2) and H2O2-RES group. Cell proliferation, differentiation and apoptosis were detected. In addition, we tested intracellular reactive oxygen species (ROS) formation and SOD activity detection of osteoblasts. The SIRT1, acetylated FoxO1 (Ac-FoxO1) and nuclear FoxO1 (Nu-FoxO1) expression were detected by western blot. KEY FINDINGS: Results revealed that RES could ameliorate bone loss and promote osteogenesis by reinforcing resistance of oxidative stress in OVX mice. RES enhanced proliferation, differentiation and suppressed apoptosis of H2O2-treated osteoblasts. In this process, SIRT1 was upregulated and the level of Nu-FoxO1, which had high transcriptional activity to regulate redox balance, significantly increased. SIGNIFICANCE: Oxidative stress plays a crucial role in osteoporosis. RES can reinforce resistance to oxidative damage and hence promote osteogenesis via the activation of SIRT1/FoxO1 signaling pathway, which provides a new idea for the prevention and treatment of osteoporosis.


Assuntos
Antioxidantes/uso terapêutico , Proteína Forkhead Box O1/metabolismo , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Resveratrol/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Animais , Antioxidantes/farmacologia , Western Blotting , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Osteoporose/diagnóstico por imagem , Osteoporose/metabolismo , Ovariectomia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Resveratrol/farmacologia , Superóxido Dismutase/sangue , Microtomografia por Raio-X
15.
J Steroid Biochem Mol Biol ; 199: 105606, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31981800

RESUMO

In 2016, the Multiple Sclerosis (MS) Society of Canada convened a panel of expert scientists, clinicians and patient advocate to review the evidence for an association between vitamin D status and MS prevention and/or disease modification. The goal was to develop clear and accurate recommendations on optimal vitamin D intake and status for people affected by MS for use in clinical practice and public health policy. The final consensus report was based on a review and grading of existing published papers combined with expert opinions of panel members. The report led to recommendations published in November of 2018 on the website of the MS Society of Canada, one in a format for use by health professionals and another in a question and answer format that was targeted to persons affected by MS and the general public. For people at risk of developing MS, the vitamin D recommendations are similar to those for the general public following the Dietary Reference Intakes (DRI) for Canada and the United States. Adults should achieve and maintain a normal vitamin D status with monitoring by physicians (serum 25-hydroxyvitamin D (25(OH)D) = 50-125 nmol/L, requiring 600-4000 IU vitamin D/d intake). For pregnant women, newborn infants, and all youth at risk of MS, vitamin D intakes should also follow DRI recommendations but additionally their serum 25-(OH)D should be monitored. For persons living with MS, existing evidence did not allow prediction of a vitamin D intake that might modify MS disease course. For this group the recommendations included: (1) serum 25-(OH)D should be maintained in the range of 50-125 nmol/L (600-4000 IU/d intake).; and (2) vitamin D should not be used as a standalone treatment for MS. For children and adolescents, serum 25OHD status was recommended to be measured upon diagnosis of a first clinical demyelinating event, and monitored every 6 months to achieve a target of 75 nmol/L Since people living with MS are at increased risk of osteoporosis, falls, and bone fractures, it was recommended to achieve a minimum serum 25OHD concentration that is protective for bone health in the general population. The revision of the MS Society recommendations on vitamin D awaits future clinical trial evidence.


Assuntos
Esclerose Múltipla/dietoterapia , Osteoporose/dietoterapia , Vitamina D/análogos & derivados , Vitamina D/uso terapêutico , Adulto , Densidade Óssea/efeitos dos fármacos , Calcifediol/efeitos adversos , Calcifediol/uso terapêutico , Canadá/epidemiologia , Criança , Suplementos Nutricionais , Feminino , Fraturas Ósseas/dietoterapia , Fraturas Ósseas/metabolismo , Fraturas Ósseas/patologia , Humanos , Lactente , Recém-Nascido , Esclerose Múltipla/sangue , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Estado Nutricional , Osteoporose/metabolismo , Gravidez , Vitamina D/efeitos adversos , Vitamina D/sangue , Deficiência de Vitamina D/dietoterapia , Deficiência de Vitamina D/metabolismo , Deficiência de Vitamina D/patologia
16.
Am J Physiol Endocrinol Metab ; 318(4): E480-E491, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31961709

RESUMO

Probiotic bacteria can protect from ovariectomy (ovx)-induced bone loss in mice. Akkermansia muciniphila is considered to have probiotic potential due to its beneficial effect on obesity and insulin resistance. The purpose of the present study was to determine if treatment with pasteurized Akkermansia muciniphila (pAkk) could prevent ovx-induced bone loss. Mice were treated with vehicle or pAkk for 4 wk, starting 3 days before ovx or sham surgery. Treatment with pAkk reduced fat mass accumulation confirming earlier findings. However, treatment with pAkk decreased trabecular and cortical bone mass in femur and vertebra of gonadal intact mice and did not protect from ovx-induced bone loss. Treatment with pAkk increased serum parathyroid hormone (PTH) levels and increased expression of the calcium transporter Trpv5 in kidney suggesting increased reabsorption of calcium in the kidneys. Serum amyloid A 3 (SAA3) can suppress bone formation and mediate the effects of PTH on bone resorption and bone loss in mice and treatment with pAkk increased serum levels of SAA3 and gene expression of Saa3 in colon. Moreover, regulatory T cells can be protective of bone and pAkk-treated mice had decreased number of regulatory T cells in mesenteric lymph nodes and bone marrow. In conclusion, treatment with pAkk protected from ovx-induced fat mass gain but not from bone loss and reduced bone mass in gonadal intact mice. Our findings with pAkk differ from some probiotics that have been shown to protect bone mass, demonstrating that not all prebiotic and probiotic factors have the same effect on bone.


Assuntos
Tecido Adiposo/crescimento & desenvolvimento , Microbioma Gastrointestinal/fisiologia , Osteoporose/metabolismo , Probióticos/farmacologia , Verrucomicrobia/metabolismo , Tecido Adiposo/metabolismo , Animais , Canais de Cálcio/metabolismo , Colo/efeitos dos fármacos , Colo/microbiologia , Feminino , Fêmur/efeitos dos fármacos , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , Hormônio Paratireóideo/metabolismo , Pasteurização , Proteína Amiloide A Sérica/metabolismo , Coluna Vertebral/efeitos dos fármacos , Linfócitos T Reguladores , Canais de Cátion TRPV/metabolismo
17.
FASEB J ; 34(2): 3037-3050, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31908035

RESUMO

Pulsed electromagnetic fields (PEMFs) and whole-body vibration (WBV) are proved to partially preserve bone mass/strength in hindlimb-unloaded and ovariectomized animals. However, the potential age-dependent skeletal response to either PEMF or WBV has not been fully investigated. Moreover, whether the coupled "mechano-electro-magnetic" signals can induce greater osteogenic potential than single stimulation remains unknown. Herein, 5-month-old or 20-month-old rats were assigned to the Control, PEMF, WBV, and PEMF + WBV groups. After 8-week treatment, single PEMF/WBV enhanced bone mass, strength, and anabolism in 5-month-old rats, but not in 20-month-old rats. PEMF + WBV induced greater increase of bone quantity, quality, and anabolism than single PEMF/WBV in young adult rats. PEMF + WBV also inhibited bone loss in elderly rats by primarily improving osteoblast and osteocyte activity, but had no effects on bone resorption. PEMF + WBV upregulated the expression of various canonical Wnt ligands and downstream molecules (p-GSK-3ß and ß-catenin), but had no impacts on noncanonical Wnt5a expression in aged skeleton, revealing the potential involvement of canonical Wnt signaling in bone anabolism of PEMF + WBV. This study not only reveals much weaker responsiveness of aged skeleton to single PEMF/WBV relative to young adult skeleton, but also presents a novel noninvasive approach based on combinatorial treatment with PEMF + WBV for improving bone health and preserving bone quantity/quality (especially for age-related osteoporosis) with stronger anabolic effects.


Assuntos
Envelhecimento , Terapia de Campo Magnético , Osteoporose , Esqueleto , Vibração , Animais , Masculino , Osteoporose/metabolismo , Osteoporose/fisiopatologia , Osteoporose/terapia , Ratos , Ratos Sprague-Dawley , Esqueleto/metabolismo , Esqueleto/fisiopatologia
18.
Molecules ; 25(1)2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31947859

RESUMO

Receptor activator of nuclear factor-κB ligand (RANKL) is a cytokine responsible for bone resorption. It binds its receptor RANK, which activates osteoporosis. High levels of osteoprotegerin (OPG) competitively binding RANKL limit formation of ligand-receptor complexes and enable bone mass maintenance. The new approach to prevent osteoporosis is searching for therapeutics that can bind RANKL and support OPG function. The aim of the study was to verify the hypothesis that isoflavones can form complexes with RANKL limiting binding of the cytokine to its receptor. Interactions of five isoflavones with RANKL were investigated by isothermal titration calorimetry (ITC), by in silico docking simulation and on Saos-2 cells. Daidzein and biochanin A showed the highest affinity for RANKL. Among studied isoflavones coumestrol, formononetin and biochanin A showed the highest potential for Saos-2 mineralization and were able to regulate the expression of RANKL and OPG at the mRNA levels, as well as osteogenic differentiation markers: alkaline phosphatase (ALP), collagen type 1, and Runt-related transcription factor 2 (Runx2). Comparison of the osteogenic activities of isoflavones showed that the use of physicochemical techniques such as ITC or in silico docking are good tools for the initial selection of substances showing a specific bioactivity.


Assuntos
Conservadores da Densidade Óssea , Isoflavonas , Simulação de Acoplamento Molecular , Osteogênese/efeitos dos fármacos , Osteoporose , Ligante RANK , Conservadores da Densidade Óssea/química , Conservadores da Densidade Óssea/farmacologia , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Humanos , Isoflavonas/química , Isoflavonas/farmacologia , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Osteoporose/patologia , Ligante RANK/agonistas , Ligante RANK/química , Ligante RANK/metabolismo
19.
EBioMedicine ; 52: 102626, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31981979

RESUMO

BACKGROUND: Forkhead box protein f1 (Foxf1) is associated with cell differentiation, and may be a key player in bone homoeostasis. However, the effect of Foxf1 on osteogenesis of bone marrow-derived mesenchymal stem cells (BMSCs) and ovariectomy-induced bone loss, as well as its clinical implications, is unknown. METHODS: By quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and western blotting, we assayed Foxf1 expression in bone tissue, BMSCs, and bone marrow-derived macrophages (BMMs), derived from ovariectomised (OVX) mice, and during osteogenic differentiation and osteoclast differentiation. Using a loss-of-function approach (small interfering RNA [siRNA]-mediated knockdown) in vitro, we examined whether Foxf1 regulates osteoblast differentiation of BMSCs via the Wnt/ß-catenin signalling pathway. Furthermore, we assessed the anabolic effect of Foxf1 knockdown (siFoxf1) in OVX mice in vivo. We also assayed the expression of Foxf1 in bone tissue derived from postmenopausal osteoporosis (PMOP) patients and its link with bone mineral density (BMD). Finally, we examined the effect of Foxf1 knockdown on the osteoblastic differentiation of human BMSCs. FINDINGS: Foxf1 expression was significantly increased in bone extract and BMSCs from OVX mice and gradually decreased during osteoblastic differentiation of BMSCs but did not differ significantly in OVX mouse-derived BMMs or during osteoclast differentiation. In vitro, Foxf1 knockdown markedly increased the expression of osteoblast specific genes, alkaline phosphatase (ALP) activity, and mineralisation. Moreover, siFoxf1 activated the Wnt/ß-catenin signalling pathway. The siFoxf1-induced increase in osteogenic differentiation was partly rescued by inhibitor of Wnt signalling (DKK1). In OVX mice, Foxf1 siRNA significantly reduced bone loss by enhancing bone formation. Foxf1 expression levels negatively correlated with reduced bone mass and bone formation in bone tissue from PMOP patients. Finally, Foxf1 knockdown significantly promoted osteogenesis by human BMSCs. INTERPRETATION: Our findings indicate that Foxf1 knockdown promotes BMSC osteogenesis and prevents OVX-induced bone loss. Therefore, Foxf1 has potential as a biomarker of osteogenesis and may be a therapeutic target for PMOP.


Assuntos
Fatores de Transcrição Forkhead/deficiência , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Osteoporose/etiologia , Osteoporose/metabolismo , Ovariectomia/efeitos adversos , Via de Sinalização Wnt , Adulto , Animais , Biomarcadores , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Camundongos , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoporose/diagnóstico por imagem , Osteoporose/patologia , Microtomografia por Raio-X , Adulto Jovem
20.
Int J Mol Sci ; 21(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948061

RESUMO

Senile osteoporosis has become a worldwide bone disease with the aging of the world population. It increases the risk of bone fracture and seriously affects human health. Unlike postmenopausal osteoporosis which is linked to menopause in women, senile osteoporosis is due to aging, hence, affecting both men and women. It is commonly found in people with more than their 70s. Evidence has shown that with age increase, bone marrow stromal cells (BMSCs) differentiate into more adipocytes rather than osteoblasts and undergo senescence, which leads to decreased bone formation and contributes to senile osteoporosis. Therefore, it is necessary to uncover the molecular mechanisms underlying the functional changes of BMSCs. It will benefit not only for understanding the senile osteoporosis development, but also for finding new therapies to treat senile osteoporosis. Here, we review the recent advances of the functional alterations of BMSCs and the related mechanisms during senile osteoporosis development. Moreover, the treatment of senile osteoporosis by aiming at BMSCs is introduced.


Assuntos
Células da Medula Óssea/metabolismo , Diferenciação Celular/fisiologia , Senescência Celular/genética , Osteoporose/metabolismo , Fatores de Transcrição/metabolismo , Adipócitos/metabolismo , Animais , Células da Medula Óssea/patologia , Diferenciação Celular/genética , Senescência Celular/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Epigênese Genética , Humanos , Osteoblastos/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/terapia , PPAR gama/genética , PPAR gama/metabolismo , Transdução de Sinais/genética , Células Estromais/metabolismo , Células Estromais/fisiologia , Fatores de Transcrição/genética
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