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1.
Epidemiol Psychiatr Sci ; 32: e10, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36786038

RESUMO

AIMS: Knowledge on the link of individual social deprivation with dementia is incomplete. We thus aimed to see whether an association with dementia risk can be observed using a recently developed Social Deprivation Index (SoDep Index). Further, as deprivation is related to depression, we investigated the role of depression in the association. METHODS: We analysed data of 11 623 Survey of Health, Ageing and Retirement in Europe (SHARE) respondents. Social deprivation status was determined by SoDep Index score. Dementia was determined by self-reported diagnosis. Dementia risk by social deprivation status was estimated using Cox proportional hazard models, including relevant covariates (gender, marriage status, chronic conditions). Depressive symptom status was added in a second step. Further, we completed subgroup analyses by social deprivation status and analysed the relevance of depressive symptoms in dementia risk in each deprivation group. In an additional sensitivity analyses we corrected for mortality and used impaired cognitive testing performance as an alternative outcome. RESULTS: High (v. low) social deprivation status was associated with an increased dementia risk (hazard ratio (HR) = 1.79 [95% CI 1.31-2.45]) in the Cox analysis adjusted for covariates only. Further adjustment for depressive symptom status indicated a largely direct association between social deprivation status and dementia risk. Moreover, compared to not having experienced depressive symptoms in the past or at baseline, those with past (HR = 1.67 [95% CI 1.23-2.25]), baseline (HR = 1.48 [95% CI 1.04-2.10]) or stable depressive symptoms (HR = 2.96 [95% CI 2.12-4.14]) had an increased dementia risk. The association between stable depressive symptom status and dementia risk was in the high social deprivation subgroup particularly pronounced. Sensitivity analyses replicated results. CONCLUSIONS: Results add to a growing body of evidence indicating that a public health approach to dementia prevention must address socioeconomic inequity. Results suggest a largely direct association between social deprivation and dementia risk. Adults who experience high social deprivation appear particularly affected by detrimental effects of depressive symptomatology on dementia risk and need intervention.


Assuntos
Demência , Aposentadoria , Adulto , Humanos , Aposentadoria/psicologia , Depressão/epidemiologia , Depressão/psicologia , Envelhecimento , Estudos Longitudinais , Europa (Continente)/epidemiologia , Demência/epidemiologia
2.
Clin Epigenetics ; 13(1): 211, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34844636

RESUMO

BACKGROUND: Ten-eleven translocation methylcytosine dioxygenase 1 (TET1) is involved in DNA demethylation and transcriptional regulation, plays a key role in the maintenance of stem cell pluripotency, and is dysregulated in malignant cells. The identification of cancer stem cells (CSCs) driving tumor growth and metastasis is the primary objective of biomarker discovery in aggressive prostate cancer (PCa). In this context, we analyzed TET1 expression in PCa. METHODS: A large-scale immunohistochemical analysis of TET1 was performed in normal prostate (NOR) and PCa using conventional slides (50 PCa specimens) and tissue microarrays (669 NOR and 1371 PCa tissue cores from 371 PCa specimens). Western blotting, RT-qPCR, and 450 K methylation array analyses were performed on PCa cell lines. Genome-wide correlation, gene regulatory network, and functional genomics studies were performed using publicly available data sources and bioinformatics tools. RESULTS: In NOR, TET1 was exclusively expressed in normal cytokeratin 903 (CK903)-positive basal cells. In PCa, TET1 was frequently detected in alpha-methylacyl-CoA racemase (AMACR)-positive tumor cell clusters and was detectable at all tumor stages and Gleason scores. Pearson's correlation analyses of PCa revealed 626 TET1-coactivated genes (r > 0.5) primarily encoding chromatin remodeling and mitotic factors. Moreover, signaling pathways regulating antiviral processes (62 zinc finger, ZNF, antiviral proteins) and the pluripotency of stem cells were activated. A significant proportion of detected genes exhibited TET1-correlated promoter hypomethylation. There were 161 genes encoding transcription factors (TFs), of which 133 were ZNF-TFs with promoter binding sites in TET1 and in the vast majority of TET1-coactivated genes. CONCLUSIONS: TET1-expressing cells are an integral part of PCa and may represent CSCs with oncogenic potential.


Assuntos
Oxigenases de Função Mista/análise , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas/análise , Idoso , Metilação de DNA/genética , Expressão Gênica/genética , Expressão Gênica/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Oxigenases de Função Mista/sangue , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/sangue , Proteínas Proto-Oncogênicas/genética
3.
Osteoporos Int ; 31(12): 2303-2311, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32767094

RESUMO

A panel of European experts was convened to establish consensus on a treat-to-target strategy in osteoporosis. Panellists agreed that the ultimate goals of treating osteoporosis are recovering pre-fracture functional level and reducing subsequent fracture risk; there was consensus that total hip bone mineral density is currently the most appropriate treatment target in clinical practice. INTRODUCTION: A modified Delphi approach was convened to establish consensus among European experts on best practice management for patients with fragility fractures and whether a treat-to-target (T2T) strategy is applicable in osteoporosis. METHODS: A panel of 12 clinical experts (from eight European countries) voted on 13 final statements relating to a T2T strategy for osteoporosis across three rounds of blinded, remotely conducted electronic surveys (Likert scale: 'strongly disagree', 'disagree', 'unable to answer', 'agree', 'strongly agree'). When panellists disagreed, they were asked how the statement could be adjusted to allow for a positive response, which was used to refine the statement for the following round. Consensus was defined as ≥ 75% agreement with a statement. Panellists were selected by UCB Pharma, which provided financial and logistical support. RESULTS: Consensus was reached for 13/13 statements. Panellists agreed that the most important goals for fragility fracture patients are recovery of pre-fracture functional level and reduction of subsequent fracture risk. There was also consensus that a T2T strategy is applicable to osteoporosis and that bone mineral density (BMD) is currently the most clinically appropriate target. With regard to the definition of a specific BMD treatment target and timeframes applicable to T2T in osteoporosis, no clear consensus was reached; panellists emphasised that these would need to be individually determined. CONCLUSIONS: According to a panel of European experts, the main goals of fracture management are to recover pre-fracture functional level and reduce fracture risk. Total hip BMD seems to be the most clinically appropriate treatment target within a T2T strategy.


Assuntos
Fraturas Ósseas , Osteoporose , Densidade Óssea , Consenso , Europa (Continente) , Humanos , Osteoporose/tratamento farmacológico
4.
Acta Biomater ; 114: 76-89, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32673749

RESUMO

Dickkopf-1 (DKK1), a Wnt inhibitor secreted by bone marrow stromal cells (MSC), is known to play an important role in long-term non-union bone fracture defects and glucocorticoid induced osteoporosis. Mitigating its effects in early bone defects could improve osteogenesis and bone defect healing. Here, we applied a biomaterial strategy to deplete a defect environment from DKK1 by scavenging the protein via a macromer-based biomaterial covalently decorated with sulfated hyaluronan (sHA3). The material consisted of cross-copolymerized three-armed macromers with a small anchor molecule. Using the glycidyl anchor, polyetheramine (ED900) could be grafted to the material to which sHA3 was efficiently coupled in a separate step. For thorough investigation of material modification, flat material surfaces were generated by fabricating them on glass discs. The binding capability of sHA3 for DKK1 was demonstrated in this study by surface plasmon resonance measurements. Furthermore, the surfaces demonstrated the ability to scavenge and inactivate pathologic amounts of DKK1 from complex media. In a combinatory approach with Wnt3a, we were able to demonstrate that DKK1 is the preferred binding partner of our sHA3-functionalized surfaces. We validated our findings in a complex in vitro setting of differentiating SaOS-2 cells and primary hMSC. Here, endogenous DKK-1 was scavenged resulting in increased osteogenic differentiation indicating that this is a consistent biological effect irrespective of the model system used. Our study provides insights in the mechanisms and efficiency of sHA3 surface functionalization for DKK1 scavenging, which may be used in a clinical context in the future.


Assuntos
Materiais Biocompatíveis , Osteogênese , Diferenciação Celular , Ácido Hialurônico , Sulfatos
5.
Neoplasia ; 21(2): 172-184, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30591422

RESUMO

Macrophages play a dual role in regulating tumor progression. They can either reduce tumor growth by secreting antitumorigenic factors or promote tumor progression by secreting a variety of soluble factors. The purpose of this study was to define the monocyte/macrophage population prevalent in skeletal tumors, explore a mechanism employed in supporting prostate cancer (PCa) skeletal metastasis, and examine a novel therapeutic target. Phagocytic CD68+ cells were found to correlate with Gleason score in human PCa samples, and M2-like macrophages (F4/80+CD206+) were identified in PCa bone resident tumors in mice. Induced M2-like macrophages in vitro were more proficient at phagocytosis (efferocytosis) of apoptotic tumor cells than M1-like macrophages. Moreover, soluble factors released from efferocytic versus nonefferocytic macrophages increased PC-3 prostate cancer cell numbers in vitro. Trabectedin exposure reduced M2-like (F4/80+CD206+) macrophages in vivo. Trabectedin administration after PC-3 cell intracardiac inoculation reduced skeletal metastatic tumor growth. Preventative pretreatment with trabectedin 7 days prior to PC-3 cell injection resulted in reduced M2-like macrophages in the marrow and reduced skeletal tumor size. Together, these findings suggest that M2-like monocytes and macrophages promote PCa skeletal metastasis and that trabectedin represents a candidate therapeutic target.


Assuntos
Neoplasias Ósseas/secundário , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Fagocitose/efeitos dos fármacos , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Trabectedina/farmacologia , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Medula Óssea , Neoplasias Ósseas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Fenótipo , Neoplasias da Próstata/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Bone ; 91: 186-93, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27497735

RESUMO

Type 2 diabetes mellitus increases skeletal fragility; however, the contributing mechanisms and optimal treatment strategies remain unclear. We studied the effects of diabetes and insulin therapy on non-enzymatic glycation (NEG), cortical porosity (Ct.Po) and biomechanics of the bone tissue in Zucker Diabetic Fatty (ZDF) rats. Eleven-week old ZDF diabetic and non-diabetic rats were given insulin to achieve glycaemic control or vehicle seven days per week over twelve weeks (insulin dose adapted individually 0.5 international units (IU) at week 1 to 13.0IU at week 12). The right femora were excised, micro-CT scanned, and tested in 3-point bending to measure biomechanics. NEG of the midshaft was determined from bulk fluorescence. Diabetes led to increased NEG (+50.1%, p=0.001) and Ct.Po (+22.9%, p=0.004), as well as to reduced mechanical competence (max. stress: -14.2%, p=0.041, toughness: -29.7%, p=0.016) in the bone tissue. NEG and Ct.Po both correlated positively to serum glucose (NEG: R(2)=0.41, p<0.001, Ct.Po: R(2)=0.34, p=0.003) and HbA1c (NEG: R(2)=0.42, p<0.001, Ct.Po: R(2)=0.28, p=0.008) levels, while NEG correlated negatively with bone biomechanics (elastic modulus: R(2)=0.21, p=0.023, yield stress: R(2)=0.17, p=0.047). Twelve weeks of insulin therapy had no significant effect on NEG or Ct.Po, and was unable to improve the mechanical competence of the bone tissue. A reduction of mechanical competence was observed in the bone tissue of the diabetic rats, which was explained in part by increased collagen NEG. Twelve weeks of insulin therapy did not alter NEG, Ct.Po or bone biomechanics. However, significant correlations between NEG and serum glucose and HbA1c were observed, both of which were reduced with insulin therapy. This suggests that a longer duration of insulin therapy may be required to reduce the NEG of the bone collagen and restore the mechanical competence of diabetic bone.


Assuntos
Osso e Ossos/fisiopatologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Insulina/uso terapêutico , Animais , Fenômenos Biomecânicos , Glicemia/metabolismo , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso Cortical/diagnóstico por imagem , Osso Cortical/efeitos dos fármacos , Osso Cortical/patologia , Osso Cortical/fisiopatologia , Diabetes Mellitus Tipo 2/sangue , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fêmur/patologia , Fêmur/fisiopatologia , Hemoglobinas Glicadas/metabolismo , Glicosilação , Insulina/farmacologia , Masculino , Minerais/metabolismo , Porosidade , Ratos Zucker
9.
Internist (Berl) ; 57(7): 631-7, 2016 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-27307159

RESUMO

Clinical diagnostics in metabolic bone diseases cover a broad spectrum of conventional and state of the art methods ranging from the medical history and clinical examination to molecular imaging. Patient treatment is carried out in an interdisciplinary team due to the multiple interactions of bone with other organ systems. Diagnosis of osteoporosis is supported by high level national guidelines. A paradigm shift concerning the clinical relevance of bone mineral density measurement renders this now to be a strong risk factor rather than a diagnostic parameter, while strengthening the value of other clinical factors for risk assessment. The impact of parameters for muscle mass, structure and function is steadily increasing in all age groups. In order to identify underlying diseases that influence bone metabolism a panel of general laboratory diagnostic parameters is recommended. Markers for bone formation and resorption and specific parameters for the regulation of calcium and phosphate metabolism should be evaluated by specialists because they require diligence in preanalytics and experience in interpretation. Genetic diagnosis is well established for rare bone diseases while diagnostic panels are not yet available for routine diagnostics in polygenetic diseases such as osteoporosis. Conventional radiology is still very important to identify, e. g. fractures, osteolytic and osteoblastic lesions and extraosseous calcifications; however tomography-based methods which combine, e. g. scintigraphy or positron emission technologies with anatomical imaging are of increasing significance. Clinical diagnostics in osteology require profound knowledge and are subject to a dynamic evolution.


Assuntos
Absorciometria de Fóton/métodos , Doenças Ósseas Metabólicas/diagnóstico , Densitometria/métodos , Testes Genéticos/métodos , Imagem Molecular/métodos , Tomografia por Emissão de Pósitrons/métodos , Doenças Ósseas Metabólicas/genética , Diagnóstico Diferencial , Humanos , Exame Físico/métodos
10.
Internist (Berl) ; 57(7): 666-74, 2016 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-27270907

RESUMO

The occurrence of bone metastases, in particular secondary to breast and prostate cancer, represents a complex medical condition that is debilitating for affected patients. In order to provide an efficient and personalized therapy, an interdisciplinary treatment approach is mandatory; therefore, systemic pharmacological therapy represents a core element of the overall treatment concept. In terms of pathophysiology, the cancer cells cause a massive disturbance of the local bone microenvironment, which as a rule leads to activation of bone resorbing osteoclasts. In addition to bisphosphonates, which can be considered classical antiresorptive agents, the monoclonal receptor activator of nuclear factor-kappa B ligand (RANKL) antibody denosumab has been in use in clinical practice since 2011. The alpha-emitting radioisotope Alpharadin was also recently approved for the treatment of metastatic prostate cancer. This article provides a summary of the most recent knowledge on the pathogenesis of how cancer cells alter the bone microenvironment as well as a review of established and future systemic treatment options.


Assuntos
Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Quimiorradioterapia Adjuvante/métodos , Neoplasias Ósseas/diagnóstico , Terapia Combinada/métodos , Denosumab/administração & dosagem , Fracionamento da Dose de Radiação , Relação Dose-Resposta a Droga , Esquema de Medicação , Medicina Baseada em Evidências , Humanos , Resultado do Tratamento
11.
Osteoporos Int ; 27(10): 2967-78, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27172934

RESUMO

UNLABELLED: This retrospective database study assessed 2-year persistence with bisphosphonates or denosumab in a large German cohort of women with a first-time prescription for osteoporosis treatment. Compared with intravenous or oral bisphosphonates, 2-year persistence was 1.5-2 times higher and risk of discontinuation was significantly lower (P < 0.0001) with denosumab. INTRODUCTION: Persistence with osteoporosis therapies is critical for fracture risk reduction. Detailed data on long-term persistence (≥2 years) with bisphosphonates and denosumab are sparse. METHODS: From the German IMS® database, we included women aged 40 years or older with a first-time prescription for bisphosphonates or denosumab between July 2010 and August 2014; patients were followed up until December 2014. The main outcome was treatment discontinuation, with a 60-day permissible gap between filled prescriptions. Two-year persistence was estimated using Kaplan-Meier survival curves, with treatment discontinuation as the failure event. Denosumab was compared with intravenous (i.v.) and oral bisphosphonates separately. Cox proportional hazard ratios (HRs) for the 2-year risk of discontinuation were calculated, with adjustment for age, physician specialty, health insurance status, and previous medication use. RESULTS: Two-year persistence with denosumab was significantly higher than with i.v. or oral bisphosphonates (39.8 % [n = 21,154] vs 20.9 % [i.v. ibandronate; n = 20,472] and 24.8 % [i.v. zoledronic acid; n = 3966] and 16.7-17.5 % [oral bisphosphonates; n = 114,401]; all P < 0.001). Patients receiving i.v. ibandronate, i.v. zoledronic acid, or oral bisphosphonates had a significantly increased risk of treatment discontinuation than did those receiving denosumab (HR = 1.65, 1.28, and 1.96-2.02, respectively; all P < 0.0001). CONCLUSIONS: Two-year persistence with denosumab was 1.5-2 times higher than with i.v. or oral bisphosphonates, and risk of discontinuation was significantly lower with denosumab than with bisphosphonates. A more detailed understanding of factors affecting medication-taking behavior may improve persistence and thereby reduce rates of fracture.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Denosumab/uso terapêutico , Difosfonatos/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Feminino , Alemanha , Humanos , Adesão à Medicação , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Cell Death Dis ; 7: e2119, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26913608

RESUMO

The Wnt inhibitor Dickkopf-1 (DKK-1) has been associated with the occurrence of bone metastases in osteotropic prostate cancer by inhibiting osteoblastogenesis. P38 mitogen-activated protein kinase (MAPK) activity is also dysregulated in advanced prostate cancer. However, the impact of p38 MAPK signaling on DKK-1 remains unknown. Inhibition of p38 MAPK signaling in osteolytic PC3 cells by small molecule inhibitors (doramapimod, LY2228820 and SB202190) suppressed DKK-1 expression, whereas activation of p38 MAPK by anisomycin increased DKK-1. Further dissection by targeting individual p38 MAPK isoforms with siRNA revealed a stronger role for MAPK11 than MAPK14 and MAPK12 in the regulation of DKK-1. Moreover, prostate cancer cells with a predominantly osteolytic phenotype produced sufficient amounts of DKK-1 to inhibit Wnt3a-induced osteoblastic differentiation in C2C12 cells. This inhibition was blocked directly by neutralizing DKK-1 using a specific antibody and also indirectly by blocking p38 MAPK. Furthermore, tissue expression in human prostate cancer revealed a correlation between p38 MAPK and DKK-1 expression with higher expression in tumor compared with normal tissues. These results reveal that p38 MAPK regulates DKK-1 in prostate cancer and may present a potential target in osteolytic prostate cancers.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Anticorpos Neutralizantes/imunologia , Diferenciação Celular , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Masculino , Proteína Quinase 11 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 11 Ativada por Mitógeno/genética , Proteína Quinase 11 Ativada por Mitógeno/metabolismo , Proteína Quinase 12 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 12 Ativada por Mitógeno/genética , Proteína Quinase 12 Ativada por Mitógeno/metabolismo , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 14 Ativada por Mitógeno/genética , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Naftalenos/farmacologia , Neoplasias da Próstata , Pirazóis/farmacologia , Piridinas/farmacologia , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/genética
13.
Osteoporos Int ; 27(2): 719-27, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26264603

RESUMO

UNLABELLED: In two large German population-based cohorts, we showed positive associations between serum thyrotropin (TSH) concentrations and the Fracture Risk Assessment score (FRAX) in men and positive associations between TSH concentrations and bone turnover markers in women. INTRODUCTION: The role of thyroid hormones on bone stiffness and turnover is poorly defined. Existing studies are confounded by differences in design and small sample size. We assessed the association between TSH serum concentrations and bone stiffness and turnover in the SHIP cohorts, which are two population-based cohorts from a region in Northern Germany comprising 2654 men and women and 3261 men and women, respectively. METHODS: We calculated the bone stiffness index using quantitative ultrasound (QUS) at the calcaneus, employed FRAX score for assessment of major osteoporotic fractures, and measured bone turnover markers, N-terminal propeptide of type I procollagen (P1NP), bone-specific alkaline phosphatase (BAP), osteocalcin, and type I collagen cross-linked C-telopeptide (CTX) in all subjects and sclerostin in a representative subgroup. RESULTS: There was no association between TSH concentrations and the stiffness index in both genders. In men, TSH correlated positively with the FRAX score both over the whole TSH range (p < 0.01) and within the reference TSH range (p < 0.01). There were positive associations between TSH concentrations and P1NP, BAP, osteocalcin, and CTX (p < 0.01) in women but not in men. There was no significant association between TSH and sclerostin levels. CONCLUSIONS: TSH serum concentrations are associated with gender-specific changes in bone turnover and stiffness.


Assuntos
Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Tireotropina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Biomarcadores/sangue , Calcâneo/diagnóstico por imagem , Estudos de Coortes , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/sangue , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Medição de Risco/métodos , Caracteres Sexuais , Ultrassonografia/métodos
14.
Bone ; 82: 116-21, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25952971

RESUMO

Type 2 diabetes mellitus increases skeletal fragility; however, the contributing mechanisms and the efficacy of bone-forming agents are unclear. We studied diabetes and parathyroid hormone (PTH) treatment effects on cortical porosity (Ct.Po), non-enzymatic glycation (NEG) and bone mechanics in Zucker diabetic fatty (ZDF) rats. Eleven-week old ZDF diabetic (DB) and non-diabetic (ND) rats were given 75µg/kg PTH (1-84) or vehicle 5days per week over 12weeks. The right femora and L4 vertebrae were excised, micro-CT scanned, and tested in 3-point bending and uniaxial compression, respectively. NEG of the samples was determined using fluorescence. Diabetes increased Ct.Po (vertebra (vert): +40.6%, femur (fem): +15.5% vs. ND group, p<0.05) but had no effect on NEG. PTH therapy reduced vertebral NEG in the ND animals only (-73% vs untreated group, p<0.05), and increased femoral NEG in the DB vs. ND groups (+63%, p<0.05). PTH therapy had no effect on Ct.Po. Diabetes negatively affected bone tissue mechanics where reductions in vertebral maximum strain (-22%) and toughness (-42%) were observed in the DB vs. ND group (p<0.05). PTH improved maximum strain in the vertebra of the ND animals (+21%, p<0.05) but did not have an effect in the DB group. PTH increased femoral maximum strain (+21%) and toughness (+28%) in ND and decreased femoral maximum stress (-13%) and toughness (-27%) in the DB animals (treated vs. untreated, p<0.05). Ct.Po correlated negatively with maximum stress (fem: R=-0.35, p<0.05, vert: R=-0.57, p<0.01), maximum strain (fem: R=-0.35, p<0.05, vert: R=-0.43, p<0.05) and toughness (fem: R=-0.34, p<0.05, vert: R=-0.55, p<0.01), and NEG correlated negatively with toughness at the femur (R=-0.34, p<0.05) and maximum strain at the vertebra (R=-0.49, p<0.05). Diabetes increased cortical porosity and reduced bone mechanics, which were not improved with PTH treatment. PTH therapy alone may worsen diabetic bone mechanics through formation of new bone with high AGEs cross-linking. Optimal treatment regimens must address both improvements of bone mass and glycemic control in order to successfully reduce diabetic bone fragility. This article is part of a Special Issue entitled "Bone and diabetes".


Assuntos
Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hormônio Paratireóideo/uso terapêutico , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Glicosilação/efeitos dos fármacos , Masculino , Hormônio Paratireóideo/farmacologia , Porosidade/efeitos dos fármacos , Ratos , Ratos Zucker , Resultado do Tratamento
15.
Bone ; 82: 108-15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26055107

RESUMO

Zucker Diabetic Fatty (ZDF) rats represent an established model of type 2 diabetes mellitus (T2DM) and display several features of human diabetic bone disease, including impaired osteoblast function, decreased bone strength, and delayed bone healing. Here, we determined whether glycemic control by insulin treatment prevents skeletal complications associated with diabetes. Subcritical femur defects were created in diabetic (fa/fa) and non-diabetic (+/+) ZDF rats. Diabetic rats were treated once daily with long-lasting insulin glargin for 12weeks for glycemic control. Insulin treatment successfully maintained serum levels of glycated hemoglobin, while untreated diabetic rats showed a 2-fold increase. Trabecular and cortical bone mass measured by µCT were decreased in diabetic rats. Insulin treatment increased bone mass of the cortical, but not of the trabecular bone compartment. Dynamic histomorphometry revealed a lower bone formation rate at the trabecular and periosteal cortical bone in diabetic animals and decreased serum procollagen type 1 N-terminal propeptide (P1NP, -49%) levels. Insulin treatment partially improved these parameters. In T2DM, serum levels of tartrate-resistant acid phosphatase (TRAP, +32%) and C-terminal telopeptide (CTX, +49%) were increased. Insulin treatment further elevated TRAP levels, but did not affect CTX levels. While diabetes impaired bone defect healing, glycemic control with insulin fully reversed these negative effects. In conclusion, insulin treatment reversed the adverse effects of T2DM on bone defect regeneration in rats mainly by improving osteoblast function and bone formation. This article is part of a Special Issue entitled Bone and diabetes.


Assuntos
Densidade Óssea/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Insulina/uso terapêutico , Animais , Densidade Óssea/fisiologia , Regeneração Óssea/fisiologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/patologia , Insulina/farmacologia , Masculino , Ratos , Ratos Zucker
16.
Sci Rep ; 5: 18138, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26667774

RESUMO

Severe vitamin D deficiency is known to cause rickets, however epidemiological studies and RCTs did not reveal conclusive associations for other parameters of bone health. In our study, we aimed to investigate the association between serum levels of 25(OH) vitamin D and bone turnover markers in a population-based sample of children. 25(OH)D, calcium (Ca), osteocalcin (OC), and ß-Crosslaps (ß-CTx) were measured in 2798 ten-year-old children from the German birth cohorts GINIplus and LISAplus. Linear regression was used to determine the association between bone turnover markers and 25(OH)D levels. 25(OH)D, OC, and ß-CTx showed a clear seasonal variation. A 10 nmol/l increase in 25(OH)D was significantly associated with a 10.5 ng/l decrease (p < 0.001) in ß-CTx after adjustment for design, sex, fasting status, time of blood drawn, BMI, growth rate, and detectable testosterone/estradiol. For OC alone no significant association with 25(OH)D was observed, whereas the ß-CTx-to-OC ratio was inversely associated with 25(OH)D (-1.7% change, p < 0.001). When stratifying the analyses by serum calcium levels, associations were stronger in children with Ca levels below the median. This study in school-aged children showed a seasonal variation of 25(OH)D and the bone turnover markers OC and ß-CTx. Furthermore a negative association between 25(OH)D and the bone resorption marker ß-CTx was observed.


Assuntos
Biomarcadores/sangue , Remodelação Óssea , Osso e Ossos/metabolismo , Vitamina D/análogos & derivados , Índice de Massa Corporal , Reabsorção Óssea/sangue , Cálcio/sangue , Criança , Estudos de Coortes , Colágeno Tipo I/sangue , Jejum/sangue , Feminino , Alemanha , Humanos , Modelos Lineares , Masculino , Osteocalcina/sangue , Peptídeos/sangue , Vigilância da População/métodos , Estações do Ano , Fatores de Tempo , Vitamina D/sangue
19.
Leukemia ; 29(2): 259-68, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25394715

RESUMO

Myelodysplastic syndromes (MDSs) represent clonal disorders mainly of the elderly that are characterized by ineffective hematopoiesis and an increased risk of transformation into acute myeloid leukemia. The pathogenesis of MDS is thought to evolve from accumulation and selection of specific genetic or epigenetic events. Emerging evidence indicates that MDS is not solely a hematopoietic disease but rather affects the entire bone marrow microenvironment, including bone metabolism. Many of these cells, in particular mesenchymal stem and progenitor cells (MSPCs) and osteoblasts, express a number of adhesion molecules and secreted factors that regulate blood regeneration throughout life by contributing to hematopoietic stem and progenitor cell (HSPC) maintenance, self-renewal and differentiation. Several endocrine factors, such as erythropoietin, parathyroid hormone and estrogens, as well as deranged iron metabolism modulate these processes. Thus, interactions between MSPC and HSPC contribute to the pathogenesis of MDS and associated pathologies. A detailed understanding of these mechanisms may help to define novel targets for diagnosis and possibly therapy. In this review, we will discuss the scientific rationale of 'osteohematology' as an emerging research field in MDS and outline clinical implications.


Assuntos
Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/patologia , Animais , Medula Óssea/patologia , Citocinas/metabolismo , Progressão da Doença , Epigênese Genética , Eritropoetina/metabolismo , Células-Tronco Hematopoéticas/citologia , Humanos , Ferro/química , Sobrecarga de Ferro/metabolismo , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Hormônio Paratireóideo/metabolismo , Transdução de Sinais
20.
Eur J Endocrinol ; 171(6): 727-35, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240499

RESUMO

OBJECTIVE: Medical management of primary hyperparathyroidism (PHPT) is important in patients for whom surgery is inappropriate. We aimed to describe clinical profiles of adults with PHPT receiving cinacalcet. DESIGN: A descriptive, prospective, observational study in hospital and specialist care centres. METHODS: For patients with PHPT, aged 23-92 years, starting cinacalcet treatment for the first time, information was collected on dosing pattern, biochemistry and adverse drug reactions (ADRs). Initial cinacalcet dosage and subsequent dose changes were at the investigator's discretion. RESULTS: Of 303 evaluable patients with PHPT, 134 (44%) had symptoms at diagnosis (mostly bone pain (58) or renal stones (50)). Mean albumin-corrected serum calcium (ACSC) at baseline was 11.4 mg/dl (2.9 mmol/l). The reasons for prescribing cinacalcet included: surgery deemed inappropriate (35%), patient declined surgery (28%) and surgery failed or contraindicated (22%). Mean cinacalcet dose was 43.9 mg/day (s.d., 15.8) at treatment start and 51.3 mg/day (31.8) at month 12; 219 (72%) patients completed 12 months treatment. The main reason for cinacalcet discontinuation was parathyroidectomy (40; 13%). At 3, 6 and 12 months from the start of treatment, 63, 69 and 71% of patients, respectively, had an ACSC of ≤10.3 mg/dl vs 9.9% at baseline. Reductions from baseline in ACSC of ≥1 mg/dl were seen in 56, 63 and 60% of patients respectively. ADRs were reported in 81 patients (27%), most commonly nausea. A total of 7.6% of patients discontinued cinacalcet due to ADRs. CONCLUSIONS: Reductions in calcium levels of ≥1 mg/dl was observed in 60% of patients 12 months after initiation of cinacalcet, without notable safety concerns.


Assuntos
Hiperparatireoidismo Primário/tratamento farmacológico , Hiperparatireoidismo Primário/epidemiologia , Naftalenos/uso terapêutico , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cinacalcete , Relação Dose-Resposta a Droga , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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