Microstructural and Strength Changes in Trabecular Bone in Elderly Patients with Type 2 Diabetes Mellitus.

Type 2 diabetes mellitus (T2DM) is one of the most common chronic diseases worldwide and it is associated with an increased risk of osteoporosis and fragility fractures. Our aim is to analyze the effect of T2DM on bone quality. This is a case-control study. The studied population consisted of 140 patients: 54 subjects with hip fracture (OP) without T2DM, 36 patients with hip fracture and T2DM (OP-T2DM), 28 patients with osteoarthritis (OA) without T2DM, and 22 patients with OA and T2DM (OA-T2DM). Bone markers, bone mineral density, FRAX score, microstructural, and bone material strength from femoral heads were assessed. The group with hip fracture presented lower BMD values than OA (p < 0.05). The OP, OP-T2DM, and OA-T2DM groups showed a decrease in bone volume fraction (BV/TV), in trabecular number (Tb.N), and in trabecular thickness (Tb.Th), while an increase was presented in the structural model index (SMI) and trabecular bone pattern factor (Tb.Pf), The groups OP, OP-T2DM, and OA-T2DM also presented lower values than those in group OA regarding the biomechanical parameters in the form of Young's modulus or elastic modulus, toughness, ultimate stress, ultimate load, extrinsic stiffness, and work to failure (p < 0.05). Our results show the negative effect of type 2 diabetes mellitus on trabecular bone structure and mechanical properties.

Effect of calcifediol treatment on cardiovascular outcomes in patients with acute coronary syndrome and percutaneous revascularization. / Efecto del tratamiento con calcifediol, sobre los episodios cardiovasculares en pacientes revascularizados tras síndrome coronario agudo.

BACKGROUND AND OBJECTIVES: Vitamin D deficiency has been consistently linked with cardiovascular diseases. However, results of intervention studies are contradictory. The aim of this study was to evaluate the effect of treatment with calcifediol (25(OH)D3) on the cardiovascular system of patients with non-ST-elevation acute coronary syndrome after percutaneous coronary intervention. PATIENTS AND METHODS: A prospective study assessing≥60-year-old patients with non-ST-elevation acute coronary syndrome, coronary artery disease and percutaneous revascularisation. We randomly assigned 41 patients (70.6±6.3 years) into 2 groups: Standard treatment+25(OH)D3 supplementation or standard treatment alone. Major adverse cardiovascular events (MACE) were evaluated at the conclusion of the 3-month follow-up period. 25(OH)D levels were analysed with regard to other relevant analytical variables and coronary disease extent. RESULTS: Basal levels of 25(OH)D≤50nmol/L were associated with multivessel coronary artery disease (RR: 2.6 [CI 95%:1.1-7.1], P=.027) and 25(OH)D≤50nmol/L+parathormone ≥65pg/mL levels correlated with increased risk for MACE (RR: 4 [CI 95%: 1.1-21.8], P=.04]. One MACE was detected in the supplemented group versus five in the control group (P=.66). Among patients with 25(OH)D levels≤50nmol/L at the end of the study, 28.6% had MACE versus 0% among patients with 25(OH)D>50nmol/L (RR: 1,4; P=.037). CONCLUSIONS: Vitamin D deficiency plus secondary hyperparathyroidism may be an effective predictor of MACE. A trend throughout the follow up period towards a reduction in MACE among patients supplemented with 25(OH)D3 was detected. 25(OH)D levels≤50nmol/L at the end of the intervention period were significantly associated with an increased number of MACE, hence, 25(OH)D level normalisation could improve cardiovascular health in addition to bone health.

SNPs in bone-related miRNAs are associated with the osteoporotic phenotype.

Biogenesis and function of microRNAs can be influenced by genetic variants in the pri-miRNA sequences leading to phenotypic variability. This study aims to identify single nucleotide polymorphisms (SNPs) affecting the expression levels of bone-related mature microRNAs and thus, triggering an osteoporotic phenotype. An association analysis of SNPs located in pri-miRNA sequences with bone mineral density (BMD) was performed in the OSTEOMED2 cohort (n = 2183). Functional studies were performed for assessing the role of BMD-associated miRNAs in bone cells. Two SNPs, rs6430498 in the miR-3679 and rs12512664 in the miR-4274, were significantly associated with femoral neck BMD. Further, we measured these BMD-associated microRNAs in trabecular bone from osteoporotic hip fractures comparing to non-osteoporotic bone by qPCR. Both microRNAs were found overexpressed in fractured bone. Increased matrix mineralization was observed after miR-3679-3p inhibition in human osteoblastic cells. Finally, genotypes of rs6430498 and rs12512664 were correlated with expression levels of miR-3679 and miR-4274, respectively, in osteoblasts. In both cases, the allele that generated higher microRNA expression levels was associated with lower BMD values. In conclusion, two osteoblast-expressed microRNAs, miR-3679 and miR-4274, were associated with BMD; their overexpression could contribute to the osteoporotic phenotype. These findings open new areas for the study of bone disorders.

Influence of high glucose and advanced glycation end-products (ages) levels in human osteoblast-like cells gene expression.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with an increased risk of osteoporotic fracture. Several factors have been identified as being potentially responsible for this risk, such as alterations in bone remodelling that may have been induced by changes in circulating glucose or/and by the presence of non-oxidative end products of glycosylation (AGEs). The aim of this study is to assess whether such variations generate a change in the gene expression related to the differentiation and osteoblast activity (OPG, RANKL, RUNX2, OSTERIX, and AGE receptor) in primary cultures of human osteoblast-like cells (hOB). METHODS: We recruited 32 patients; 10 patients had osteoporotic hip fractures (OP group), 12 patients had osteoporotic hip fractures with T2DM (T2DM group), and 10 patients had hip osteoarthritis (OA group) with no osteoporotic fractures and no T2DM. The gene expression was analyzed in hOB cultures treated with physiological glucose concentration (4.5 mM) as control, high glucose (25 mM), and high glucose plus AGEs (2 µg/ml) for 24 h. RESULTS: The hOB cultures from patients with hip fractures presented slower proliferation. Additionally, the hOB cultures from the T2DM group were the most negatively affected with respect to RUNX2 and OSX gene expression when treated solely with high glucose or with high glucose plus AGEs. Moreover, high levels of glucose induced a major decrease in the RANKL/OPG ratio when comparing the OP and the T2DM groups to the OA group. CONCLUSIONS: Our data indicates an altered bone remodelling rate in the T2DM group, which may, at least partially, explain the reduced bone strength and increased incidence of non-traumatic fractures in diabetic patients.

Circulating sclerostin and estradiol levels are associated with inadequate response to bisphosphonates in postmenopausal women with osteoporosis.

INTRODUCTION: The biological mechanisms associated with an inadequate response to treatment with bisphosphonates are not well known. This study investigates the association between circulating levels of sclerostin and estradiol with an inadequate clinical outcome to bisphosphonate therapy in women with postmenopausal osteoporosis. METHODS: This case-control study is based on 120 Spanish women with postmenopausal osteoporosis being treated with oral bisphosphonates. Patients were classified as adequate responders (ARs, n=66, mean age 68.2±8 years) without incident fractures during 5 years of treatment, or inadequate responders (IRs, n=54, mean age 67±9 years), with incident fractures between 1 and 5 years of treatment. Bone mineral density (DXA), structural analysis of the proximal femur and structural/fractal analysis of the distal radius were assessed. Sclerostin concentrations were measured by ELISA and 17ß-estradiol levels by radioimmunoassay based on ultrasensitive methods. RESULTS: In the ARs group, sclerostin serum levels were significantly lower (p=0.02) and estradiol concentrations significantly higher (p=0.023) than in the IRs group. A logistic regression analysis was performed, including as independent variables in the original model femoral fracture load, 25 hydroxyvitamin D, previus history of fragility fracture, sclerostin and estradiol. Only previous history of fragility fracture (OR 14.04, 95% CI 2.38-82.79, p=0.004) and sclerostin levels (OR 1.11, 95% CI 1.02-1.20, p=0.011), both adjusted by estradiol levels remained associated with IRs. Also, sclerostin concentrations were associated with the index of resistance to compression (IRC) in the fractal analysis of the distal radius, a parameter on bone microstructure. CONCLUSIONS: Sclerostin and estradiol levels are associated with the response to bisphosphonate therapy in women with postmenopausal osteoporosis.

Response to Denosumab Treatment for 2 Years in an Adolescent With Osteoradionecrosis.

Radiotherapy, an essential component of cancer treatment, is not without risk to bone, particularly to the immature or growing skeleton. Known side effects range from post-radiation osteitis to osteoradionecrosis. We report the case of a 14-year-old male patient undergoing denosumab treatment, a new antiresorptive agent, for osteoradionecrosis. The patient exhibited fractures and associated pain and functional limitations secondary to radiation for the treatment of an embryonal rhabdomyosarcoma of prostate grade III administered at age 5 years. After treatment with denosumab, the pain disappeared, bone remodeling markers dramatically declined, bone mass increased, and pathological bone scan findings resolved without adverse effects or new fractures.

POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes) treated with autologous hematopoietic stem cell transplantation: a case report and literature review.

BACKGROUND: POEMS syndrome is a rare systemic pathology of paraneoplastic origin that is associated with plasma cell dyscrasia. It is characterized by the presence of sensorimotor polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes, and other systemic manifestations. The pathogenesis of the syndrome is unknown but over-production of vascular endothelial growth factor is probably responsible for most of the more characteristic symptoms. There is no standard treatment for POEMS syndrome and no randomized controlled clinical trials of treatment exist in the available literature. High-dose melphalan with autologous hematopoietic stem cell transplantation should be considered for younger patients with widespread osteosclerotic lesions, and for patients with rapidly progressive neuropathy. CASE REPORT: This is the case of a 62-year-old Caucasian man who was admitted to our center presenting pretibial edema accompanied by significant weight loss and difficulty walking. POEMS criteria were present and an immunofixation test confirmed the presence of a monoclonal plasmaproliferative disorder. After autologous hematopoietic stem cell transplantation, the monoclonal component disappeared and the patient's clinical status improved markedly. CONCLUSIONS: Autologous hematopoietic stem cell transplantation following high-dose melphalan is an effective therapy for younger patients with widespread osteosclerotic lesions in POEMS syndrome.

Microstructural trabecular bone from patients with osteoporotic hip fracture or osteoarthritis: its relationship with bone mineral density and bone remodelling markers.

Osteoporosis (OP) and osteoarthritis (OA) are the most prevalent musculoskeletal disorders in the elderly but the relationship between them is unclear. The purposes of this study are to analyze the bone turnover markers (BTM), bone mineral density (BMD) and the structural and mechanical properties of trabecular bone in patients with OP and OA, and to explore the relationship between these two diseases. We studied 12 OP patients and 13 OA patients. We analyzed BTM (ß-CrossLaps and PINP), BMD and microstructural and biomechanical parameters (micro-CT). Our results were: OP group has higher levels of ß-CrossLaps and lower BMD at the femoral neck. Also, OP patients have a decreased volume of trabecular bone and less trabecular number, with architecture showing prevalence of rod-like trabeculae and worse connectivity than OA patients. The biomechanical parameters were worse in OP patients. BMD was correlated with almost all the structural and biomechanical parameters. Moreover, ß-CrossLaps was negatively correlated with hip BMD and with bone surface density and positively with trabecular separation. BTM, BMD and bone microstructural changes in osteoporosis are opposite to those of OA. These findings justify a less resistant bone with higher risk of fragility fractures in OP patients. These histomorphometric and biomechanical changes may be suspected by measuring of BMD and ß-CrossLaps levels.

Immunotherapy reduces allergen-mediated CD66b expression and myeloperoxidase levels on human neutrophils from allergic patients.

UNLABELLED: CD66b is a member of the carcinoembryonic antigen family, which mediates the adhesion between neutrophils and to endothelial cells. Allergen-specific immunotherapy is widely used to treat allergic diseases, and the molecular mechanisms underlying this therapy are poorly understood. The present work was undertaken to analyze A) the in vitro effect of allergens and immunotherapy on cell-surface CD66b expression of neutrophils from patients with allergic asthma and rhinitis and B) the in vivo effect of immunotherapy on cell-surface CD66b expression of neutrophils from nasal lavage fluid during the spring season. Myeloperoxidase expression and activity was also analyzed in nasal lavage fluid as a general marker of neutrophil activation. RESULTS: CD66b cell-surface expression is upregulated in vitro in response to allergens, and significantly reduced by immunotherapy (p<0.001). Myeloperoxidase activity in nasal lavage fluid was also significantly reduced by immunotherapy, as were the neutrophil cell-surface expression of CD66b and myeloperoxidase (p<0.001). Interestingly, CD66b expression was higher in neutrophils from nasal lavage fluid than those from peripheral blood, and immunotherapy reduced the number of CD66+MPO+ cells in nasal lavage fluid. Thus, immunotherapy positive effects might, at least in part, be mediated by the negative regulation of the CD66b and myeloperoxidase activity in human neutrophils.

Differences in osteogenic and apoptotic genes between osteoporotic and osteoarthritic patients.

BACKGROUND: Osteoporosis is a metabolic disorder characterized by a reduction in bone mass and deterioration in the microarchitectural structure of the bone, leading to a higher risk for spontaneous and fragility fractures.The main aim was to study the differences between human bone from osteoporotic and osteoarthritic patients about gene expression (osteogenesis and apoptosis), bone mineral density, microstructural and biomechanic parameters. METHODS: We analyzed data from 12 subjects: 6 with osteoporotic hip fracture (OP) and 6 with hip osteoarthritis (OA), as the control group. All subjects underwent medical history, analytical determinations, densitometry, histomorphometric and biochemical study. The expression of 86 genes of osteogenesis and 86 genes of apoptosis was studied in pool of bone samples from patients with OP and OA by PCR array. RESULTS: We observed that most of the genes of apoptosis and osteogenesis show a decrease in gene expression in the osteoporotic group in comparison with the osteoarthritic group. The histomorphometric study shows a lower bone quality in the group of patients with hip fractures compared to the osteoarthritic group. CONCLUSIONS: The bone tissue of osteoporotic fracture patients is more fragile than the bone of OA patients. Our results showed an osteoporotic bone with a lower capacities for differentiation and osteoblastic activity as well as a lower rate of apoptosis than osteoarthritic bone. These results are related with structural and biochemical parameters.

Study of bone mass in young daughters of women with fracture of the distal end of the radius.

The main aim was to assess whether young and healthy daughters of women with fractures of the distal end of the radius (DER) had less bone mass than the control group. In an observational study of cases and controls (1:1), the daughters of women with fractures of DER (96) were selected at the age of reaching the peak of bone mass and compared with a control group (91). All women underwent medical history, analytical determinations, and densitometry. In the case group, we found lower bone mass values at the spine and femoral neck than the control group. We also found a lower bone mass at the hips of daughters of women with 1 or more osteoporotic fractures associated with DER and at the lumbar spine in those whose mothers had densitometric osteoporosis. In conclusion, young daughters of women with fractures of DER had lower levels of bone mass density, with a possible "location-specific" occurrence based on the presence of 1 or more osteoporotic fractures associated with DER or on the presence of maternal densitometric osteoporosis.

Vertebral fractures in patients with inflammatory bowel disease compared with a healthy population: a prospective case-control study.

BACKGROUND: A prospective study was performed to compare the prevalence of morphometric vertebral fractures (MVF) between patients with inflammatory bowel disease (IBD) and healthy subjects and to identify predictive factors of fracture. METHODS: A total of 107 patients with IBD (53 with Crohn's disease and 54 with ulcerative colitis) and 51 healthy subjects participated in the study. Information about anthropometric parameters, toxins, previous fractures, and parameters related to this disease were evaluated. The index of vertebral deformity, bone mass density (BMD), and biochemical parameters were calculated. RESULTS: A total of 72 fractures were detected in 38.32% of patients with IBD, and 10 fractures were detected in 13.73% of healthy subjects; the risk of fracture in patients with IBD was higher than that in control subjects (OR, 4.03; 95% CI, 1.652-9.847; p < 0.002). We found no correlation between fracture and BMD in patients with IBD (lumbar spine, r = -0.103, p = 0.17 and femoral neck, r = -0.138, p = 0.07). Corticosteroid treatment was not associated with prevalent vertebral fractures nor with taking corticosteroids (r = 0.135, p = 0.14) or the duration for which they were taken (r = 0.08, p = 0.38), whereas this relationship was present in the controls (r = -0.365, p = 0.01). In the multivariate analysis, none of the measured parameters were significantly predictive of fracture, only to manifested IBD. Hypovitaminosis D was observed in 55.14% of patients with IBD. CONCLUSIONS: The prevalence of morphometric vertebral fractures is higher in patients with IBD than in the healthy population, without association with BMD or corticoid treatment. Simply having IBD was proven to be a predictive factor of fracture. We observed a high incidence of hypovitaminosis D in patients with IBD.

Risk factors for prediction of inadequate response to antiresorptives.

Some patients sustain fractures while on antiresorptives. Whether this represents an inadequate response (IR) to treatment or a chance event has not been elucidated. We performed a study to identify which patients are more likely to fracture while on treatment. This is a multicentric, cross-sectional study of postmenopausal women on antiresorptives for osteoporosis in 12 Spanish hospitals, classified as adequate responders (ARs) if on treatment with antiresorptives for 5 years with no incident fractures or inadequate responders (IRs) if an incident fracture occurred between 1 and 5 years on treatment. Poor compliance, secondary osteoporosis, and previous anti-osteoporosis treatment other than the assessed were exclusion criteria. Clinical, demographic, analytical, dual-energy X-ray absorptiometry (DXA) variables, and proximal femur structure analysis (ImaTx™) and structural/fractal analyses of distal radius were performed. A total of 179 women (76 IRs; mean (SD): age 68.2 (9.0) years; 103 ARs, age 68.5 (7.9) years) were included. History of prior fracture (p = 0.005), two or more falls in the previous year (p = 0.032), low lumbar spine bone mineral density (BMD) (p = 0.02), 25 hydroxyvitamin D (p = 0.017), and hip ImaTx fracture load index (p = 0.004) were associated with IR. In the logistic regression models a fracture before treatment (odds ratio [OR], 3.60; 95% confidence interval [CI], 1.47-8.82; p = 0.005) and levels of 25 hydroxyvitamin D below 20 ng/mL (OR, 3.89; 95% CI, 1.55-9.77; p = 0.004) significantly increased risk for IR, while increased ImaTx fracture load (OR, 0.96; 95% CI, 0.93-0.99; p = 0.006; per every 100 units) was protective, although the latter became not significant when all three variables were fitted into the model. Therefore, we can infer that severity of the disease, with microarchitectural and structure deterioration, as shown by previous fracture and hip analysis, and low levels of 25 hydroxy vitamin D carry higher risk of inadequate response to antiresorptives. More potent regimes should be developed and adequate supplementation implemented to solve this problem.

Beta-blocker use is associated with fragility fractures in postmenopausal women with coronary heart disease.

BACKGROUND AND AIMS: An association between cardiovascular disease and osteoporosis is described. A number of drugs often used by patients with coronary heart disease, such as thiazides, statins and beta-blockers, have shown controversial effects on bone. 1) To study the possible association between coronary heart disease (CHD) and bone mass density (BMD), quantitative ultrasound measurements (QUS) and the prevalence of fragility and vertebral fractures. 2) To study the possible influence of a number of drugs, statins, thiazides and beta-blockers, on BMD and fractures. METHODS: Case-control study performed on 74 postmenopausal women who had recently suffered from CHD, and 111 age-matched controls. BMD was measured by Dual X-Ray Absorptiometry (DXA) at the lumbar spine and proximal femur. Quantitative Ultrasound (QUS) was also measured at the heel. Vertebral fractures were diagnosed by lateral, thoracic and lumbar X-rays. The occurrence of non-vertebral fractures was determined by examination of medical records. RESULTS: Patients with CHD had higher values of BMI. They had a higher prevalence of arterial hypertension and hyperlipidemia, and consequently higher consumption of beta-blockers and statins, but not of thiazides, and had lower alcohol consumption. Patients with CHD had higher BMD values, measured by DXA at the proximal femur, than controls, but there were no differences in DXA values at the lumbar spine or QUS at the heel between the two groups. The prevalence of all fragility factures was slightly higher in patients with CHD, but not to a significant extent. The prevalence of vertebral fractures was similar in the two groups. In a logistic analysis to identify factors associated with all fractures, beta-blockers were positively associated with fragility fractures, and DXA at the femoral neck was inversely associated with fragility fractures. CONCLUSIONS: Postmenopausal women with CHD have higher values of BMD at the proximal femur but, despite this, show a slight but non-significant increase in the prevalence of fragility fractures. Beta-blockers are independently associated with fragility fractures, but thiazides and statins are not.

Alendronate and raloxifene affect the osteoprotegerin/RANKL system in human osteoblast primary cultures from patients with osteoporosis and osteoarthritis.

The osteoprotegerin/RANKL system modulates bone remodelling. Alendronate and raloxifene are anti-resorptive drugs effective in osteoporotic disease. They reduce fracture risk, the activity of bone remodelling and increase bone mineral density. It is not known if they can exert a direct effect in osteoblasts via the osteoprotegerin/RANKL system. Our objective was to assess the effects of alendronate and raloxifene among osteoprotegerin production (ELISA), as well as osteoprotegerin and RANKL expression (RT-PCR), in primary cultures of human osteoblasts (hOB). We compared 17 osteoporotic patients with 16 patients affected by osteoarthritis in basal conditions and after incubation with alendronate (10(-6) M), raloxifene (10(-7) M) or 17-ß estradiol (10(-7) M) for 24 h. The statistical analysis was determined by ANOVA. Osteoprotegerin protein secretion in hOB cultures was higher in patients with osteoporosis than osteoarthritis. Osteoprotegerin secretion levels remained unchanged after each treatment. The osteoporotic group was more sensitive to treatment. Both raloxifene (34%) and estradiol (37%) increased osteoprotegerin mRNA expression, and alendronate (118%) and raloxifene (61%) increased the mRNA expression of RANKL. The RANKL/osteoprotegerin mRNA ratio was higher in osteoporotic than osteoarthritic patients. In the osteoporotic group, the RANKL/osteoprotegerin mRNA ratio was significantly increased after treatment with alendronate (112%) and after treatment with raloxifene (60%). These results indicate a direct action of alendronate and raloxifene on hOB cultures from osteoporotic patients, and the cited drugs are able to modulate the osteoprotegerin/RANKL system.

Bone mineral density and risk of fractures in aging, obese post-menopausal women with type 2 diabetes. The GIUMO Study.

BACKGROUND AND AIMS: Type 2 diabetes mellitus (DM) has a high prevalence in aging obese postmenopausal women. It is not clear whether or not diabetes produces an increase in bone mineral density or an increase in fracture rates. OBJECTIVE: The main objective of this study was to investigate whether type 2 DM produces a higher prevalence of vertebral, hip and non-vertebral fractures in obese postmenopausal Caucasian women. A secondary objective was to study the influence of DM in quantitative ultrasound measurements of the heel (QUS) and bone mineral density (BMD) measured by dual X-ray absorptiometry (DXA), in both lumbar spine (L2-L4) and proximal femur. METHOD: This study was a prospective cohort of 111 patients with type 2 DM and 91 control individuals (CTR) over age 65 and obese, recruited from 16 centers in Spain. MAIN OUTCOME MEASURES: Lateral dorsal and lumbar X-rays were performed to assess vertebral fractures. Hip and non-vertebral fractures were noted from medical records, written reports or Xray studies. QUS measurements were made of the calcaneus and BMD measurements of the lumbar spine (L2-L4) and proximal femur. RESULTS: Patients had higher BMD in the lumbar spine (L2-L4) than controls (0.979 g/cm2 vs 0.927 g/cm2, p=0.035), but we found no statistically significant differences in the proximal femur. QUS measurements showed similar values in both groups: BUA (69.3 dB/Mhz vs 66.7 dB/Mhz, p=0.291), SOS (1537 m/sg vs 1532 m/sg, p=0.249) and QUI (87.5 vs 83.7, p=0.153). No statistically significant differences were found in any case. There was no association between vertebral, hip and non-vertebral fractures and DM. The crude odds ratio, without adjusting was 1.045 (CI 95% 0.531 ; 2.059), and the adjusted odds ratio was 0.927 (CI 95% 0.461 ; 1.863). CONCLUSIONS: In obese postmenopausal Caucasian women, type 2 DM produces an increase in BMD of the lumbar spine without changes in BMD of the proximal femur or in QUS measurements of the heel. The prevalence of vertebral, hip and non-vertebral fractures did not increase in type 2 DM.

RANKL/OPG in primary cultures of osteoblasts from post-menopausal women. Differences between osteoporotic hip fractures and osteoarthritis.

The OPG/RANKL/RANK system is important in the balance between bone formation and resorption. We used primary human osteoblasts (hOBs) cells to examine the impact of 17-beta-estradiol (E2) or/and 1,25-dihydroxyvitamin D (1,25D) in OPG/RANKL system in 28 post-menopausal (PM) women; (a) with hip fracture (OP) or (b) with osteoarthritis (OA). The hOB from OP patients proliferated slower during the first stage, than the OA women (31.5+/-2.6 and 21.4+/-1.3 days, respectively, p<0.05). The OP group secreted significantly higher OPG protein levels than the OA women (10.1+/-2.6 and 4.4+/-0.8pmol/L, respectively, p<0.05). The 1,25D and 1,25D+E2 induce an increase in RANKL and RANKL/OPG mRNA expression in OP patients above 200% (p<0.05). HOBs from the osteoporotic hip initially proliferate slower but after reaching the first cellular confluence, the proliferation rate is equal in both groups. Furthermore, hOBs from hips with OP present a higher protein secretion of OPG, and higher RANKL and RANKL/OPG expression ratio in response to 1,25D and 1,25D+E2, than hOBs from OA women. All this could suggest that the greater bone loss that characterizes OP patients can be mediated due to differences in the secretion and expression of the RANKL/OPG system in response to different stimuli.

[Evolution of bone mass in children and adolescents with type 1 diabetes mellitus]. / Evolución de la masa ósea durante la infancia y adolescencia en niños con diabetes mellitus tipo 1.

BACKGROUND AND OBJECTIVE: There is some controversy over bone mineral density (BMD) in children and teenagers with type 1 diabetes mellitus (DM1). We evaluated BMD by dual-energy X-ray absorptiometry (DXA) and correlated it with anthropometric, biochemical and hormonal parameters related to bone metabolism. PATIENTS AND METHOD: Sixty-six patients with DM1 (26 males and 40 females) aged between 3 and 17 years, and 327 controls with a similar age were studied. RESULTS: The BMD of all diabetic patients was not different from that of the controls. However, the subgroup of older males (between 15 and 17 years) had a significantly inferior BMD than controls of the same age: mean (standard deviation), 0.888 (0.13) versus 0.994 (0.11) (p = 0.027). BMD was inferior to -1 standard deviation (Z-score) in 21.2% of diabetic children. All the biochemical and hormonal parameters were within the normality rank. There was a negative correlation between the evolution time of the disease and the levels of 25-hydroxycholecalciferol (r = -0.345; p = 0.006). We did not observe any correlation between BMD and the remaining studied parameters. CONCLUSIONS: These results confirm that initially children and adolescents with non-complicated DM1 have no alteration of the bone mass. Yet the BMD physiological increase is smaller in the diabetic population than in controls during the adolescence period, which may cause a lower peak of bone mass in these patients.

Large-scale analysis of association between polymorphisms in the transforming growth factor beta 1 gene (TGFB1) and osteoporosis: the GENOMOS study.

INTRODUCTION: The TGFB1 gene which encodes transforming growth factor beta 1, is a strong candidate for susceptibility to osteoporosis and several studies have reported associations between bone mineral density (BMD), osteoporotic fractures and polymorphisms of TGFB1, although these studies have yielded conflicting results. METHODS: We investigated associations between TGFB1 polymorphisms and BMD and fracture in the GENOMOS study: a prospective multicenter study involving 10 European research studies including a total of 28,924 participants. Genotyping was conducted for known TGFB1 polymorphisms at the following sites: G-1639-A (G-800-A, rs1800468), C-1348-T (C-509-T, rs1800469), T29-C (Leu10Pro, rs1982073), G74-C (Arg25Pro, rs1800471) and C788-T (Thr263Ile, rs1800472). These polymorphisms were genotyped prospectively and methodology was standardized across research centers. Genotypes and haplotypes were related to BMD at the lumbar sine and femoral neck and fractures. RESULTS: There were no significant differences in either women or men at either skeletal site for any of the examined polymorphisms with the possible exception of a weak association with reduced BMD (-12 mg/cm2) in men with the T-1348 allele (p<0.05). None of the haplotypes was associated with BMD and none of the polymorphisms or haplotypes significantly affected overall risk of fractures, however, the odds ratio for incident vertebral fracture in carriers of the rare T788 allele was 1.64 (95% CI: 1.09-2.64), p<0.05. CONCLUSIONS: This study indicates that polymorphic variation in the TGFB1 gene does not play a major role in regulating BMD or susceptibility to fractures. The weak associations we observed between the C-1348-T and lumbar spine BMD in men and between C788-T and risk of incident vertebral fractures are of interest but could be chance findings and will need replication in future studies.