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1.
J Bone Miner Res ; 31(2): 358-68, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26256109

RESUMEN

Protein phosphorylation regulates a wide variety of cellular processes. Thus, we hypothesize that single-nucleotide polymorphisms (SNPs) that may modulate protein phosphorylation could affect osteoporosis risk. Based on a previous conventional genome-wide association (GWA) study, we conducted a three-stage meta-analysis targeting phosphorylation-related SNPs (phosSNPs) for femoral neck (FN)-bone mineral density (BMD), total hip (HIP)-BMD, and lumbar spine (LS)-BMD phenotypes. In stage 1, 9593 phosSNPs were meta-analyzed in 11,140 individuals of various ancestries. Genome-wide significance (GWS) and suggestive significance were defined by α = 5.21 × 10(-6) (0.05/9593) and 1.00 × 10(-4), respectively. In stage 2, nine stage 1-discovered phosSNPs (based on α = 1.00 × 10(-4)) were in silico meta-analyzed in Dutch, Korean, and Australian cohorts. In stage 3, four phosSNPs that replicated in stage 2 (based on α = 5.56 × 10(-3), 0.05/9) were de novo genotyped in two independent cohorts. IDUA rs3755955 and rs6831280, and WNT16 rs2707466 were associated with BMD phenotypes in each respective stage, and in three stages combined, achieving GWS for both FN-BMD (p = 8.36 × 10(-10), p = 5.26 × 10(-10), and p = 3.01 × 10(-10), respectively) and HIP-BMD (p = 3.26 × 10(-6), p = 1.97 × 10(-6), and p = 1.63 × 10(-12), respectively). Although in vitro studies demonstrated no differences in expressions of wild-type and mutant forms of IDUA and WNT16B proteins, in silico analyses predicts that WNT16 rs2707466 directly abolishes a phosphorylation site, which could cause a deleterious effect on WNT16 protein, and that IDUA phosSNPs rs3755955 and rs6831280 could exert indirect effects on nearby phosphorylation sites. Further studies will be required to determine the detailed and specific molecular effects of these BMD-associated non-synonymous variants.


Asunto(s)
Densidad Ósea/genética , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Proteínas Wnt/genética , Estudios de Cohortes , Femenino , Cuello Femoral/metabolismo , Humanos , Vértebras Lumbares/metabolismo , Masculino , Fosforilación , Proteínas Wnt/metabolismo
2.
Hum Mol Genet ; 24(16): 4710-27, 2015 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25941324

RESUMEN

MicroRNAs (miRNAs) are critical post-transcriptional regulators. Based on a previous genome-wide association (GWA) scan, we conducted a polymorphism in microRNA target sites (poly-miRTS)-centric multistage meta-analysis for lumbar spine (LS)-, total hip (HIP)- and femoral neck (FN)-bone mineral density (BMD). In stage I, 41 102 poly-miRTSs were meta-analyzed in seven cohorts with a genome-wide significance (GWS) α = 0.05/41 102 = 1.22 × 10(-6). By applying α = 5 × 10(-5) (suggestive significance), 11 poly-miRTSs were selected, with FGFRL1 rs4647940 and PRR5 rs3213550 as top signals for FN-BMD (P = 7.67 × 10(-6) and 1.58 × 10(-5)) in gender-combined sample. In stage II in silico replication (two cohorts), FGFRL1 rs4647940 was the only signal marginally replicated for FN-BMD (P = 5.08 × 10(-3)) at α = 0.10/11 = 9.09 × 10(-3). PRR5 rs3213550 was also selected based on biological significance. In stage III de novo genotyping replication (two cohorts), FGFRL1 rs4647940 was the only signal significantly replicated for FN-BMD (P = 7.55 × 10(-6)) at α = 0.05/2 = 0.025 in gender-combined sample. Aggregating three stages, FGFRL1 rs4647940 was the single stage I-discovered and stages II- and III-replicated signal attaining GWS for FN-BMD (P = 8.87 × 10(-12)). Dual-luciferase reporter assays demonstrated that FGFRL1 3' untranslated region harboring rs4647940 appears to be hsa-miR-140-5p's target site. In a zebrafish microinjection experiment, dre-miR-140-5p is shown to exert a dramatic impact on craniofacial skeleton formation. Taken together, we provided functional evidence for a novel FGFRL1 poly-miRTS rs4647940 in a previously known 4p16.3 locus, and experimental and clinical genetics studies have shown both FGFRL1 and hsa-miR-140-5p are important for bone formation.


Asunto(s)
Regiones no Traducidas 3' , Densidad Ósea/genética , Sitios Genéticos , MicroARNs/genética , Polimorfismo Genético , Receptor Tipo 5 de Factor de Crecimiento de Fibroblastos/genética , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino
3.
Arch Osteoporos ; 9: 197, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25311734

RESUMEN

UNLABELLED: The aim of this study was to determine the vitamin D response to sunlight ultraviolet radiation in older people. Increases in vitamin D depended on the season of exposure, but the changes were small. Natural sun exposure is not a practical intervention for vitamin D deficiency in this population. PURPOSE: The purpose of this study is to measure the ultraviolet radiation (UVR) exposure of those in residential aged care in an earlier trial of sunlight exposure and to determine its effect on their vitamin D response. METHODS: Attendance data, demographic, clinical and biochemical variables for 248 participants were used for a secondary analysis of a previous cluster randomized trial of sunlight exposure and falls. The ambient solar UV Index data were used to calculate the participants' UVR dose. Multiple linear regression was used to test if UVR exposure over 6 months, as measured by the standard erythemal dose (SED), was a predictor of vitamin D response, controlling for age, gender, BMI, calcium intake, baseline vitamin D and season of exposure. RESULTS: The median 25-hydroxyvitamin D (25OHD) was 32.4 nmol/L at baseline and 34.6 nmol/L at 6 months (p = 0.35). The significant predictors of 25OHD at 6 months were UVR exposures in spring-summer (coefficient = 0.105, 95 % confidence interval (CI) 0.001-0.209, p = 0.05) and autumn-winter (coefficient = 0.056, 95 % CI 0.005-0.107, p = 0.03) and baseline vitamin D (adjusted coefficient = 0.594, 95 % CI 0.465-0.724, p = 0.00). In those starting sunlight sessions in spring, an increase of 1 unit in log SED was associated with 11 % increase in 25OHD. CONCLUSIONS: Natural UVR exposure can increase 25OHD levels in older people in residential care, but depends on the season of exposure. However, due to inadequate sun exposure, 25OHD did not reach optimal levels. Nevertheless, where sun exposure is encouraged in this group, the focus for the start of exposure should be in the months of spring or autumn, as this timing was associated with a vitamin D response.


Asunto(s)
Luz Solar , Deficiencia de Vitamina D/prevención & control , Vitamina D/análogos & derivados , Anciano de 80 o más Años , Calcio , Femenino , Humanos , Masculino , Radiometría , Vitamina D/sangre
4.
Epilepsia ; 55(10): 1551-7, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25124647

RESUMEN

OBJECTIVES: Chronic treatment with valproate (VPA) is commonly associated with weight gain, which potentially has important health implications, in particular increased central fat distribution. We utilized a VPA-discordant same-sex, twin and matched sibling pair study design to primarily examine for differences in fat distribution between patients with epilepsy treated with VPA compared to their matched twin or sibling control. Weight, blood pressure, and leptin levels were assessed. METHODS: Height, weight, waist and hip measurements, exercise, blood pressure (BP), and serum leptin levels were measured. Body composition was measured using dual-energy x-ray absorptiometry (DXA). Abdominal fat was expressed as a percentage of the abdominal region (AFat%); and of whole body fat (WBF); (AFat%WBF). Mean within-pair differences were assessed (VPA-user and nonuser). Restricted maximum likelihood (REML) linear mixed model analysis was fitted to examine associations of anthropometrics, zygosity, gender, menopausal status, VPA dose and duration, with weight and AFat%. RESULTS: We studied 19 pairs of VPA-discordant, gender-matched (five male, 14 female) twins and siblings. Mean (standard deviation, SD) duration of therapy for VPA users was 11.0 (7.4) years. There were no statistically significant within-pair differences in age, height, weight, body mass index (BMI), BP, leptin level, WBF, AFat%, or AFat%WBF. For pairs in which VPA-user was treated for >11 years there were statistically significant mean within-pair differences in AFat%, (+7.1%, p = 0.03, n = 10 pairs), mean BP (+11.0 mm Hg, p = 0.006, n = 8 pairs); but not in AFat%WBF. VPA duration was positively associated with weight (estimate +0.98 kg/per year of VPA, p = 0.03); VPA treatment duration and dose were not significantly associated with AFat%. SIGNIFICANCE: This study demonstrated a relationship between long-term VPA use and abdominal adiposity (AFat%), which could have significant health implications. We recommend ongoing monitoring of weight, BMI, and blood pressure for patients taking VPA.


Asunto(s)
Anticonvulsivantes/efectos adversos , Distribución de la Grasa Corporal , Ácido Valproico/efectos adversos , Aumento de Peso/efectos de los fármacos , Grasa Abdominal/efectos de los fármacos , Absorciometría de Fotón , Adulto , Anticonvulsivantes/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Composición Corporal/efectos de los fármacos , Enfermedades en Gemelos/tratamiento farmacológico , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Leptina/sangre , Masculino , Factores Sexuales , Hermanos , Gemelos Dicigóticos , Gemelos Monocigóticos , Ácido Valproico/uso terapéutico
5.
Hum Mol Genet ; 23(7): 1923-33, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24249740

RESUMEN

Aiming to identify novel genetic variants and to confirm previously identified genetic variants associated with bone mineral density (BMD), we conducted a three-stage genome-wide association (GWA) meta-analysis in 27 061 study subjects. Stage 1 meta-analyzed seven GWA samples and 11 140 subjects for BMDs at the lumbar spine, hip and femoral neck, followed by a Stage 2 in silico replication of 33 SNPs in 9258 subjects, and by a Stage 3 de novo validation of three SNPs in 6663 subjects. Combining evidence from all the stages, we have identified two novel loci that have not been reported previously at the genome-wide significance (GWS; 5.0 × 10(-8)) level: 14q24.2 (rs227425, P-value 3.98 × 10(-13), SMOC1) in the combined sample of males and females and 21q22.13 (rs170183, P-value 4.15 × 10(-9), CLDN14) in the female-specific sample. The two newly identified SNPs were also significant in the GEnetic Factors for OSteoporosis consortium (GEFOS, n = 32 960) summary results. We have also independently confirmed 13 previously reported loci at the GWS level: 1p36.12 (ZBTB40), 1p31.3 (GPR177), 4p16.3 (FGFRL1), 4q22.1 (MEPE), 5q14.3 (MEF2C), 6q25.1 (C6orf97, ESR1), 7q21.3 (FLJ42280, SHFM1), 7q31.31 (FAM3C, WNT16), 8q24.12 (TNFRSF11B), 11p15.3 (SOX6), 11q13.4 (LRP5), 13q14.11 (AKAP11) and 16q24 (FOXL1). Gene expression analysis in osteogenic cells implied potential functional association of the two candidate genes (SMOC1 and CLDN14) in bone metabolism. Our findings independently confirm previously identified biological pathways underlying bone metabolism and contribute to the discovery of novel pathways, thus providing valuable insights into the intervention and treatment of osteoporosis.


Asunto(s)
Densidad Ósea/genética , Claudinas/genética , Osteonectina/genética , Osteoporosis/genética , Anciano , Huesos/metabolismo , Femenino , Cuello Femoral/fisiología , Expresión Génica , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Cadera/fisiología , Humanos , Vértebras Lumbares/fisiología , Masculino , Persona de Mediana Edad , Osteoclastos/citología , Osteogénesis/genética , Osteoporosis/terapia , Polimorfismo de Nucleótido Simple
6.
Ann Rheum Dis ; 72(7): 1141-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22993228

RESUMEN

OBJECTIVE: Lumbar disc degeneration (LDD) is an important cause of low back pain, which is a common and costly problem. LDD is characterised by disc space narrowing and osteophyte growth at the circumference of the disc. To date, the agnostic search of the genome by genome-wide association (GWA) to identify common variants associated with LDD has not been fruitful. This study is the first GWA meta-analysis of LDD. METHODS: We have developed a continuous trait based on disc space narrowing and osteophytes growth which is measurable on all forms of imaging (plain radiograph, CT scan and MRI) and performed a meta-analysis of five cohorts of Northern European extraction each having GWA data imputed to HapMap V.2. RESULTS: This study of 4600 individuals identified four single nucleotide polymorphisms with p<5×10(-8), the threshold set for genome-wide significance. We identified a variant in the PARK2 gene (p=2.8×10(-8)) associated with LDD. Differential methylation at one CpG island of the PARK2 promoter was observed in a small subset of subjects (ß=8.74×10(-4), p=0.006). CONCLUSIONS: LDD accounts for a considerable proportion of low back pain and the pathogenesis of LDD is poorly understood. This work provides evidence of association of the PARK2 gene and suggests that methylation of the PARK2 promoter may influence degeneration of the intervertebral disc. This gene has not previously been considered a candidate in LDD and further functional work is needed on this hitherto unsuspected pathway.


Asunto(s)
Degeneración del Disco Intervertebral/genética , Vértebras Lumbares , Ubiquitina-Proteína Ligasas/genética , Adulto , Anciano , Islas de CpG , Metilación de ADN , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Degeneración del Disco Intervertebral/diagnóstico , Degeneración del Disco Intervertebral/etnología , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Población Blanca/genética
7.
Ann Rheum Dis ; 72(6): 911-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22730372

RESUMEN

OBJECTIVES: Patients with osteoarthritis have increased bone mass but no decrease in fractures. The association between self-reported osteoarthritis and incident falls and fractures was studied in postmenopausal women. METHODS: The Global Longitudinal Study of Osteoporosis in Women is a prospective multinational cohort of 60,393 non-institutionalised women aged ≥55 years who had visited primary care practices within the previous 2 years. Questionnaires were mailed at yearly intervals. Patients were classified as having osteoarthritis if they answered yes to the question, 'Has a doctor or other health provider ever said that you had osteoarthritis or degenerative joint disease?', and this was validated against primary care records in a subsample. Information on incident falls, fractures and covariates was self-reported. Cox and Poisson models were used for incident fractures and number of falls, respectively, to compute hazard ratios (HRs) and rate ratios (RRs) for baseline osteoarthritis status. RESULTS: Of 51 386 women followed for a median of 2.9 years (interquartile range 2.1-3.0), 20 409 (40%) reported osteoarthritis. The adjusted HR for osteoarthritis predicting fracture was 1.21 (95% CI 1.13 to 1.30; p<0.0001) and the adjusted RR for falls was 1.24 (95% CI 1.22 to 1.26; p<0.0001). However, the association between osteoarthritis and fracture was not significant after adjustment for incident falls (HR 1.06 (95% CI 0.98 to 1.15; p=0.13)). CONCLUSIONS: Postmenopausal women with self-reported osteoarthritis have a 20% increased risk of fracture and experience 25% more falls than those without osteoarthritis. These data suggest that increased falls are the causal pathway of the association between osteoarthritis and fractures.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Fracturas Óseas/epidemiología , Osteoartritis/epidemiología , Posmenopausia , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Estimación de Kaplan-Meier , Persona de Mediana Edad , Distribución de Poisson , Prevalencia , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Riesgo , Autoinforme , Encuestas y Cuestionarios
8.
Ann Rheum Dis ; 72(2): 179-86, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23117245

RESUMEN

BACKGROUND: Strontium ranelate is currently used for osteoporosis. The international, double-blind, randomised, placebo-controlled Strontium ranelate Efficacy in Knee OsteoarthrItis triAl evaluated its effect on radiological progression of knee osteoarthritis. METHODS: Patients with knee osteoarthritis (Kellgren and Lawrence grade 2 or 3, and joint space width (JSW) 2.5-5 mm) were randomly allocated to strontium ranelate 1 g/day (n=558), 2 g/day (n=566) or placebo (n=559). The primary endpoint was radiographical change in JSW (medial tibiofemoral compartment) over 3 years versus placebo. Secondary endpoints included radiological progression, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and knee pain. The trial is registered (ISRCTN41323372). RESULTS: The intention-to-treat population included 1371 patients. Treatment with strontium ranelate was associated with smaller degradations in JSW than placebo (1 g/day: -0.23 (SD 0.56) mm; 2 g/day: -0.27 (SD 0.63) mm; placebo: -0.37 (SD 0.59) mm); treatment-placebo differences were 0.14 (SE 0.04), 95% CI 0.05 to 0.23, p<0.001 for 1 g/day and 0.10 (SE 0.04), 95% CI 0.02 to 0.19, p=0.018 for 2 g/day. Fewer radiological progressors were observed with strontium ranelate (p<0.001 and p=0.012 for 1 and 2 g/day). There were greater reductions in total WOMAC score (p=0.045), pain subscore (p=0.028), physical function subscore (p=0.099) and knee pain (p=0.065) with strontium ranelate 2 g/day. Strontium ranelate was well tolerated. CONCLUSIONS: Treatment with strontium ranelate 1 and 2 g/day is associated with a significant effect on structure in patients with knee osteoarthritis, and a beneficial effect on symptoms for strontium ranelate 2 g/day.


Asunto(s)
Antirreumáticos/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Osteoartritis de la Rodilla/tratamiento farmacológico , Tiofenos/uso terapéutico , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Radiografía , Resultado del Tratamiento
9.
Bone ; 52(1): 400-6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23111314

RESUMEN

OBJECTIVE: Oxidative stress has been linked to osteoporosis. Serum uric acid (UA), a strong endogenous antioxidant, has been associated with higher bone mineral density (BMD), lower bone turnover and lower prevalence of fractures in a large cross-sectional study of men. Whether this relationship is present in women and how UA relates to changes in BMD longitudinally has not been examined. METHODS: A sample of 356 peri- and postmenopausal women, mean age 60.5 years was studied. Each individual had baseline BMD and body composition measurements by dual energy x-ray absorptiometry (DXA) and at least one repeat measure, on average 9.7 years later. Annual rate of change in BMD (A%ΔBMD) was calculated. UA was measured at each DXA visit. Calciotropic hormones and bone turnover markers were measured at the final visit only. RESULTS: Cross-sectional data analyses revealed that women with higher UA levels had significantly higher absolute BMD measures at all skeletal sites. These women also had higher measures of body weight and its components such as lean mass (LM) and fat mass (FM). Results of multiple regression analyses showed a positive association between UA and BMD that remained significant even after accounting for possible confounders including LM and FM. Regression analyses of the longitudinal BMD data demonstrated significant associations between serum UA levels and annual rates of change in BMD at all skeletal sites. After adjustment associations remained significant for lumbar spine, forearm and whole body BMD but not for hip BMD. CONCLUSION: Higher serum UA levels appear to be protective for bone loss in peri- and postmenopausal women and this relationship is not affected by changes in body composition measures.


Asunto(s)
Perimenopausia , Posmenopausia , Ácido Úrico/sangre , Absorciometría de Fotón , Anciano , Densidad Ósea , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Osteoporosis/sangre
10.
Bone ; 52(1): 120-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23023015

RESUMEN

INTRODUCTION: Osteoporosis related risk factors such as BMD have been associated with cardiovascular endpoints in previous studies but there have been no studies of integrated risk using risk factor algorithms. METHODS: A sample of 358 peri- and postmenopausal women, mean age 59.3 (range 45-74) years were studied. Each individual had bone mineral density (BMD) measurements by dual energy X-ray absorptiometry. Fracture risk was assessed using the WHO FRAX algorithm and cardiovascular disease (CVD) risk using the Framingham Risk Tool. RESULTS: Women with higher 10 year risk of major osteoporotic had significantly higher cardiovascular risk (4.634% vs 8.36%, p=0.001). In multiple regression analysis, 5-year CVD risk was significantly associated with the 10-year risk of having major osteoporotic (ß=0.095, p=0.001) and hip (ß=0.055, p=0.001) fracture. Women with the highest CVD risk were 5.4 times more likely to have higher risk of major osteoporotic fracture. CONCLUSIONS: Fracture risk, determined by using a multiple risk factor algorithm such as FRAX, was positively associated with higher cardiovascular risk determined by using the Framingham Risk Tool. Awareness regarding these concurrent risk factors needs to be raised so that appropriate risk reduction can be implemented.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Osteoporosis/epidemiología , Posmenopausia , Anciano , Índice de Masa Corporal , Enfermedades Cardiovasculares/complicaciones , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis/complicaciones , Factores de Riesgo
11.
Ther Adv Musculoskelet Dis ; 4(4): 287-92, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22859927

RESUMEN

Bone is a target in many inflammatory rheumatic diseases. Inflammation leads to a wide range of changes in bone, and especially bone remodeling. In ankylosing spondylitis (AS) bone loss has been documented, but measuring bone density in the spine is hampered by new bone formation in syndesmophytes, periost and within the vertebrae. The risk of vertebral fractures is increased in AS. The diagnosis of vertebral fractures requires imaging and adequate evaluation of vertebral heights. In addition, in the ankysosed spine segments, additional imaging is often needed to diagnose spinal fractures at unusual locations (cervical spine) or in the posterior arch structures. Risk factors for vertebral fractures are helpful for case finding. Fracture prevention is indicated in high risk patients with AS, especially when they have already a vertebral fracture or in the presence of osteoporosis.

12.
PLoS One ; 7(8): e42617, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22912713

RESUMEN

RUNX2 is an essential transcription factor required for skeletal development and cartilage formation. Haploinsufficiency of RUNX2 leads to cleidocranial displaysia (CCD) a skeletal disorder characterised by gross dysgenesis of bones particularly those derived from intramembranous bone formation. A notable feature of the RUNX2 protein is the polyglutamine and polyalanine (23Q/17A) domain coded by a repeat sequence. Since none of the known mutations causing CCD characterised to date map in the glutamine repeat region, we hypothesised that Q-repeat mutations may be related to a more subtle bone phenotype. We screened subjects derived from four normal populations for Q-repeat variants. A total of 22 subjects were identified who were heterozygous for a wild type allele and a Q-repeat variant allele: (15Q, 16Q, 18Q and 30Q). Although not every subject had data for all measures, Q-repeat variants had a significant deficit in BMD with an average decrease of 0.7SD measured over 12 BMD-related parameters (p = 0.005). Femoral neck BMD was measured in all subjects (-0.6SD, p = 0.0007). The transactivation function of RUNX2 was determined for 16Q and 30Q alleles using a reporter gene assay. 16Q and 30Q alleles displayed significantly lower transactivation function compared to wild type (23Q). Our analysis has identified novel Q-repeat mutations that occur at a collective frequency of about 0.4%. These mutations significantly alter BMD and display impaired transactivation function, introducing a new class of functionally relevant RUNX2 mutants.


Asunto(s)
Densidad Ósea/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Cuello Femoral/diagnóstico por imagen , Glutamina , Mutación , Secuencias Repetitivas de Aminoácido , Activación Transcripcional/genética , Adulto , Anciano , Anciano de 80 o más Años , Animales , Displasia Cleidocraneal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/química , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Femenino , Fracturas del Cuello Femoral/genética , Fracturas del Cuello Femoral/fisiopatología , Cuello Femoral/metabolismo , Cuello Femoral/fisiología , Cuello Femoral/fisiopatología , Predisposición Genética a la Enfermedad/genética , Células HEK293 , Humanos , Ratones , Método de Montecarlo , Células 3T3 NIH , Receptores de Calcitriol/metabolismo , Ultrasonografía
13.
PLoS Genet ; 8(7): e1002745, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22792071

RESUMEN

We aimed to identify genetic variants associated with cortical bone thickness (CBT) and bone mineral density (BMD) by performing two separate genome-wide association study (GWAS) meta-analyses for CBT in 3 cohorts comprising 5,878 European subjects and for BMD in 5 cohorts comprising 5,672 individuals. We then assessed selected single-nucleotide polymorphisms (SNPs) for osteoporotic fracture in 2,023 cases and 3,740 controls. Association with CBT and forearm BMD was tested for ∼2.5 million SNPs in each cohort separately, and results were meta-analyzed using fixed effect meta-analysis. We identified a missense SNP (Thr>Ile; rs2707466) located in the WNT16 gene (7q31), associated with CBT (effect size of -0.11 standard deviations [SD] per C allele, P = 6.2 × 10(-9)). This SNP, as well as another nonsynonymous SNP rs2908004 (Gly>Arg), also had genome-wide significant association with forearm BMD (-0.14 SD per C allele, P = 2.3 × 10(-12), and -0.16 SD per G allele, P = 1.2 × 10(-15), respectively). Four genome-wide significant SNPs arising from BMD meta-analysis were tested for association with forearm fracture. SNP rs7776725 in FAM3C, a gene adjacent to WNT16, was associated with a genome-wide significant increased risk of forearm fracture (OR = 1.33, P = 7.3 × 10(-9)), with genome-wide suggestive signals from the two missense variants in WNT16 (rs2908004: OR = 1.22, P = 4.9 × 10(-6) and rs2707466: OR = 1.22, P = 7.2 × 10(-6)). We next generated a homozygous mouse with targeted disruption of Wnt16. Female Wnt16(-/-) mice had 27% (P<0.001) thinner cortical bones at the femur midshaft, and bone strength measures were reduced between 43%-61% (6.5 × 10(-13)

Asunto(s)
Densidad Ósea/genética , Fracturas Óseas/genética , Estudio de Asociación del Genoma Completo , Osteoporosis/genética , Proteínas Wnt/genética , Adolescente , Adulto , Animales , Densidad Ósea/fisiología , Huesos/fisiología , Niño , Preescolar , Femenino , Fémur , Antebrazo , Humanos , Masculino , Ratones , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Factores de Riesgo
14.
J Bone Miner Res ; 27(5): 963-74, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22467094

RESUMEN

Osteoporosis may be a lifelong condition. Robust data regarding the efficacy and safety of both long-term osteoporosis therapy and therapy discontinuation are therefore important. A paucity of clinical trial data regarding the long-term antifracture efficacy of osteoporosis therapies necessitates the use of surrogate endpoints in discussions surrounding long-term use and/or discontinuation. Long-term treatment (beyond 3-4 years) may produce further increases in bone mineral density (BMD) or BMD stability, depending on the specific treatment and the skeletal site. Bisphosphonates, when discontinued, are associated with a prolonged reduction in bone turnover markers (BTMs), with a very gradual increase to pretreatment levels within 3 to 60 months of treatment cessation, depending on the bisphosphonate used and the prior duration of therapy. In contrast, with nonbisphosphonate antiresorptive agents, such as estrogen and denosumab, BTMs rebound to above pretreatment values within months of discontinuation. The pattern of BTM change is generally mirrored by a more or less rapid decrease in BMD. Although the prolonged effect of some bisphosphonates on BTMs and BMD may contribute to residual benefit on bone strength, it may also raise safety concerns. Adequately powered postdiscontinuation fracture studies and conclusive evidence on maintenance or loss of fracture benefit is lacking for bisphosphonates. Similarly, the effects of rapid reversal of bone turnover upon discontinuation of denosumab on fracture risk remain unknown. Ideally, studies evaluating the effects of long-term treatment and treatment discontinuation should be designed to provide head-to-head "offset" data between bisphosphonates and nonbisphosphonate antiresorptive agents. In the absence of this, a clinical recommendation for physicians may be to periodically assess the benefits/risks of continuation versus discontinuation versus alternative management strategies.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Fracturas Óseas/tratamiento farmacológico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Difosfonatos/uso terapéutico , Femenino , Humanos , Factores de Riesgo , Tiempo
15.
Drugs Aging ; 29(2): 157-65, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22276959

RESUMEN

BACKGROUND: The Drug Burden Index (DBI), a measure of an individual's exposure to anticholinergic and sedative medications, is associated with functional impairment in community-dwelling, older people. In people from residential aged care facilities (RACFs), DBI score does not appear to be associated with functional impairment, but is associated with an increased risk of falls. OBJECTIVE: We investigated the associations between increasing DBI score and mortality in older adults living in RACFs. METHODS: Study participants (n = 602; 70.9% female), recruited from 51 RACFs in Sydney, Australia, had a mean ± standard deviation (SD) age of 85.7 ± 6.4 years and a mean ± SD DBI score of 0.58 ± 0.64. RESULTS: Exposure to anticholinergic medication was 33.6% and sedative medications 41.9%. All-cause mortality after a variable follow-up time (774-1269 days) was 36.2% (n = 218), with the leading causes of death classified as stroke (n = 46; 21.1%), ischaemic heart disease/cardiovascular system (n = 44; 20.2%) and pneumonia (n = 31; 14.2%). One-year mortality multivariate models showed that the DBI categories low (n = 260; hazard ratio [HR] 1.13; 95% CI 0.82, 1.57) and high (n = 153; HR 1.19; 95% CI 0.82, 1.74) were not associated with mortality. This lack of a significant association remained after dichotomization into the anticholinergic and sedative components of the DBI. CONCLUSIONS: We found that with high exposure to anticholinergic and sedative medications, there was no significant association between increasing DBI score and all-cause mortality in old individuals living in RACFs. Further research into the adverse effects of medication use on the mortality of institutionalized older individuals is needed.


Asunto(s)
Antagonistas Colinérgicos , Hipnóticos y Sedantes , Mortalidad , Instituciones Residenciales/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Análisis Multivariante
16.
Rheumatology (Oxford) ; 51(2): 250-61, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21586523

RESUMEN

OBJECTIVE: To examine the association between work place exposure and CTS by meta-analysis, including analyses with respect to exposure to hand force, repetition, vibration and wrist posture. METHODS: All relevant peer-reviewed articles published between January 1980 and December 2009 were identified by a systematic search using the MEDLINE, CINAHL and PubMed databases. Papers were critiqued independently by two researchers and the relevant exposure information was extracted. Using the raw data of exposed and unexposed cases, a cumulative effect of specific exposure risks were calculated for hand force, repetition, a combination of force and repetition, vibration and wrist posture using the statistical program, Stata version 11 (StataCorp, College Station, TX, USA). Heterogeneity, meta-regression, publication bias and subgroup sensitivity analyses were performed. RESULTS: Thirty-seven studies from English-language literature met the inclusion criteria. Using National Institute for Occupational Health and Safety criteria for case definition, a significant positive association between CTS and hand force, repetition, use of vibratory tools and wrist posture was observed with approximate doubling of risk for all exposures. Significant heterogeneity among studies was observed for most exposures and metaregression analyses identified CTS case definition, study design, country and risk of bias score to be the significant determinants. When a more conservative definition of CTS was employed to include nerve conduction abnormality with symptoms and/or signs, risk factors significantly associated with an increased risk of CTS among exposed workers were: vibration [odds ratio (OR) 5.40; 95% CI 3.14, 9.31], hand force (OR 4.23; 95% CI 1.53, 11.68) and repetition (OR 2.26; 95% CI 1.73, 2.94). There was a non-significant trend for the association between CTS and combined exposure to both force and repetition (OR 1.85; 95% CI 0.99, 3.45) and wrist posture (OR 4.73; 95% CI 0.42, 53.32). CONCLUSION: Occupational exposure to excess vibration, increased hand force and repetition increase the risk of developing CTS. Workplace strategies to avoid overexposure to these risk factors should be implemented.


Asunto(s)
Síndrome del Túnel Carpiano/etiología , Exposición Profesional/efectos adversos , Trastornos de Traumas Acumulados/complicaciones , Traumatismos de la Mano/complicaciones , Humanos , Postura , Factores de Riesgo , Vibración/efectos adversos , Muñeca
17.
Arch Gerontol Geriatr ; 54(2): e234-41, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21924507

RESUMEN

PURPOSE OF RESEARCH: The purpose of this study was to investigate the factors influencing low adherence with therapeutic sunlight exposure in a randomized controlled trial conducted with older people living in intermediate care facilities. MATERIALS AND METHODS: The study involved participants in the FREEDOM (Falls Risk Epidemiology: Effect of vitamin D on skeletal Outcomes and other Measures) study, a randomized controlled trial of therapeutic sun exposure to reduce falls in older people in intermediate care facilities. Semi-structured interviews were conducted with thirty participants in the FREEDOM trial, and with ten sunlight officers who were employed to facilitate the sun exposure. Two focus groups involving 10 participants in the FREEDOM trial were also held at the end of the intervention period. Common themes were derived from the interview and focus group transcripts. PRINCIPAL RESULTS: The study showed that the perceived health benefits did not influence adherence with the sun exposure. Factors such as socializing with others and being outdoors were more important in encouraging attendance. The main barriers to adherence included the perceived inflexibility and regimentation of daily attendance, clash with other activities, unsuitable timing and heat discomfort. MAJOR CONCLUSIONS: This study showed that providing greater flexibility and autonomy to older people in how and when they receive sun exposure is likely to improve adherence.


Asunto(s)
Instituciones de Cuidados Intermedios , Cooperación del Paciente , Fototerapia , Luz Solar , Accidentes por Caídas/prevención & control , Anciano , Anciano de 80 o más Años , Femenino , Grupos Focales , Humanos , Entrevistas como Asunto , Masculino , Fototerapia/métodos , Fototerapia/psicología
18.
Arthritis Rheum ; 64(1): 88-98, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21905006

RESUMEN

OBJECTIVE: To investigate whether protease-activated receptor 1 (PAR-1) and/or PAR-2 promotes the invasiveness/proliferation of synovial fibroblasts (SFs) and to determine the signaling mechanisms of these pathways. METHODS: SFs were isolated from the synovial tissue of patients with rheumatoid arthritis (RA), patients with osteoarthritis (OA), and PAR-1- or PAR-2-knockout (KO) mice. Expression of PAR-1 and PAR-2 was detected by immunofluorescence and Western blotting. The invasion and proliferation of SFs were measured by invasion assay and MTT assay, respectively. Matrix metalloproteinase 2 (MMP-2) and MMP-9 were detected by zymography, and cytokines were measured by enzyme-linked immunosorbent assay. RESULTS: PAR-1 and PAR-2 were colocalized with SFs in RA and OA synovium and, to a considerably lesser extent, in normal synovium. Inhibition of PAR-2 by small interfering RNA (siRNA) inhibited RASF invasion and proliferation, whereas blocking of PAR-1 by siRNA had the reverse effects. SFs from PAR-2-KO mice exhibited slower rates of proliferation and invasion. SFs from PAR-1-KO mice produced less MMP-2 and, in response to tumor necrosis factor α (TNFα) stimulation, had increased MMP-9 secretion when compared to SFs from wild-type and PAR-2-KO mice. Inhibition of PAR-1, but not PAR-2, stimulated the secretion of interleukin-17 (IL-17) and TNFα by RASFs. Furthermore, PAR-1 and PAR-2 had opposing effects on the activation of ERK, p38, and NF-κB. CONCLUSION: Activation of PAR-1 stimulates MMP-2 secretion, inhibits RASF growth and invasion, and decreases production of IL-17 and TNFα by RASFs, whereas activation of PAR-2 stimulates RASF growth and invasion and increases production of TNFα. Thus, although PAR-1 and PAR-2 are coexpressed by RASFs, PAR-2 alone appears to be responsible for the aggressive properties of RASFs and is likely to contribute to the pathologic progression of RA.


Asunto(s)
Artritis Reumatoide/metabolismo , Fibroblastos/metabolismo , Receptor PAR-1/metabolismo , Receptor PAR-2/metabolismo , Membrana Sinovial/metabolismo , Anciano , Animales , Artritis Reumatoide/genética , Artritis Reumatoide/patología , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Formazáns/metabolismo , Humanos , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Osteoartritis , Osteoartritis de la Rodilla/genética , Osteoartritis de la Rodilla/metabolismo , Osteoartritis de la Rodilla/patología , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Receptor PAR-1/deficiencia , Receptor PAR-1/genética , Receptor PAR-2/deficiencia , Receptor PAR-2/genética , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/patología , Sales de Tetrazolio/metabolismo , Transfección , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/farmacología
19.
J Bone Miner Res ; 27(3): 645-53, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22113888

RESUMEN

Previous fractures of the hip, spine, or wrist are well-recognized predictors of future fracture, but the role of other fracture sites is less clear. We sought to assess the relationship between prior fracture at 10 skeletal locations and incident fracture. The Global Longitudinal Study of Osteoporosis in Women (GLOW) is an observational cohort study being conducted in 17 physician practices in 10 countries. Women aged ≥55 years answered questionnaires at baseline and at 1 and/or 2 years (fractures in previous year). Of 60,393 women enrolled, follow-up data were available for 51,762. Of these, 17.6%, 4.0%, and 1.6% had suffered 1, 2, or ≥3 fractures, respectively, since age 45 years. During the first 2 years of follow-up, 3149 women suffered 3683 incident fractures. Compared with women with no previous fractures, women with 1, 2, or ≥3 prior fractures were 1.8-, 3.0-, and 4.8-fold more likely to have any incident fracture; those with ≥3 prior fractures were 9.1-fold more likely to sustain a new vertebral fracture. Nine of 10 prior fracture locations were associated with an incident fracture. The strongest predictors of incident spine and hip fractures were prior spine fracture (hazard ratio [HR] = 7.3) and hip (HR = 3.5). Prior rib fractures were associated with a 2.3-fold risk of subsequent vertebral fracture, and previous upper leg fracture predicted a 2.2-fold increased risk of hip fracture. Women with a history of ankle fracture were at 1.8-fold risk of future fracture of a weight-bearing bone. Our findings suggest that a broad range of prior fracture sites are associated with an increased risk of incident fractures, with important implications for clinical assessments and risk model development.


Asunto(s)
Fracturas Óseas/complicaciones , Osteoporosis/complicaciones , Anciano , Femenino , Fracturas Óseas/etiología , Humanos , Persona de Mediana Edad , Factores de Riesgo , Encuestas y Cuestionarios
20.
Bone ; 50(1): 289-95, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22061864

RESUMEN

BACKGROUND: We studied 265 men (mean age 56.4 years; range 18-83 years), among patients enrolled in two arms of a double-blind, 1-year study comparing the effects of zoledronic acid (ZOL) with risedronate (RIS) in patients either commencing (prednisolone 7.5 mg/day or equivalent) (prevention arm, n=88) or continuing glucocorticoid therapy (treatment arm, n=177). METHODS: Patients received either a single ZOL 5 mg infusion or RIS 5 mg oral daily at randomization, along with calcium (1000 mg) and vitamin D (400-1200 IU). Primary endpoint: difference in percentage change from baseline in bone mineral density (BMD) at the lumbar spine (LS) at 12 months. Secondary endpoints: percentage changes in BMD at total hip (TH) and femoral neck (FN), relative changes in bone turnover markers (ß-CTx and P1NP), and overall safety. FINDINGS: In the treatment subpopulation, ZOL increased LS BMD by 4.7% vs. 3.3% for RIS and at TH the percentage changes were 1.8% vs. 0.2%, respectively. In the prevention subpopulation, bone loss was prevented by both treatments. At LS the percentage changes were 2.5% vs. -0.2% for ZOL vs. RIS and at TH the percentage changes were 1.1% vs. -0.4%, respectively. ZOL significantly increased lumbar spine BMD more than RIS at Month 12 in both the prevention population (p=0.0024) and the treatment subpopulation (p=0.0232) in men. In the treatment subpopulation, ZOL demonstrated a significantly greater reduction in serum ß-CTx and P1NP relative to RIS at all time-points. In the prevention subpopulation, ZOL significantly reduced ß-CTx at all time-points, and P1NP at Month 3 (p=0.0297) only. Both treatments were well tolerated in men, albeit with a higher incidence of influenza-like illness and pyrexia events post-infusion with ZOL. INTERPRETATION: Once-yearly ZOL preserves or increases BMD within 1 year to a greater extent than daily RIS in men receiving glucocorticoid therapy.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/uso terapéutico , Ácido Etidrónico/análogos & derivados , Glucocorticoides/efectos adversos , Imidazoles/uso terapéutico , Osteoporosis/inducido químicamente , Osteoporosis/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/farmacología , Difosfonatos/farmacología , Método Doble Ciego , Ácido Etidrónico/farmacología , Ácido Etidrónico/uso terapéutico , Cuello Femoral/anatomía & histología , Cuello Femoral/efectos de los fármacos , Glucocorticoides/farmacología , Glucocorticoides/uso terapéutico , Articulación de la Cadera/anatomía & histología , Articulación de la Cadera/efectos de los fármacos , Humanos , Imidazoles/farmacología , Vértebras Lumbares/anatomía & histología , Vértebras Lumbares/efectos de los fármacos , Masculino , Persona de Mediana Edad , Osteoporosis/patología , Ácido Risedrónico , Adulto Joven , Ácido Zoledrónico
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