Bone Abstracts

Denosumab (DMAb) significantly improves bone strength at the hip, estimated by FEA from QCT scans, from baseline (B/L) and vs placebo (Pbo) (Keaveny ASBMR 2010). We determined the extent and distribution of mass and thickness changes at the proximal femur, a key skeletal site for fracture risk, using a novel cortical bone mapping technique on the same serial QCT scans. A FREEDOM substudy included 80 women who underwent hip QCT scanning at B/L and months 12, 24 and 36 during DM...

Aim: Differences in fracture risk between ethnic groups have been documented. The basis for these differences is yet incomplete and the age at what ethnic differences appear is uncertain. Assessment of bone health in pediatric populations could bring insights on factors compromising bone accrual. We describe here differences in total body bone mineral density (TB-BMD) in a unique setting of children of the same age, measured with the same device (iDXA) different ethnic backgro...

Lack of Klotho, the co-receptor for the bone-derived hormone fibroblast growth factor-23 (FGF23), leads to a severe impairment in bone mineralization in mice. However, the mechanisms underlying the Klotho deficiency-associated defects in bone mineralization are still poorly understood. Here, we sought to elucidate the vitamin D independent role of Klotho in bone mineralization. To ablate increased vitamin D signaling in Klotho knockout mice (Kl−/−), we c...

It is well known that the epidermal growth factor receptor (EGFR), its ligands, and the structurally related receptor ERBB2/neu are expressed in skeletal cells. However, the functions of EGFR ligands in bone cells remain poorly defined. In this study, we employed a transgenic mouse line overexpressing the EGFR ligand amphiregulin (AREG) specifically in osteoblasts under the α1(I)-collagen promoter. AREG-tg mice did not show changes in body weight or gross phenotype. Compa...

Calcium (Ca) and vitamin D nutritional status effects on oral health were evaluated in 85 healthy women aged between 20 and 30 years (24.6±0.4). They attended the first year of the Nutrition Carrier at the Private University (ISALUD, Buenos Aires, Argentine). Usual Ca intake (CaI) was determined by a food-frequency questionnaire that included consumption of dairy products and calcium-enriched foods. Blood samples were obtained in a fasting state in winter: the end of Augu...

Background: The tyrosine kinase inhibitor (TKI) imatinib is applied as front-line treatment in adult and pediatric patients with chronic myeloid leukemia (CML) in order to selectively inhibit the causative oncogenic BCR-ABL1 tyrosine kinase. However, TKIs exhibit off-target effects on further kinases involved in the regulation of bone metabolism. As consequence, pediatric patients display longitudinal growth retardation while on imatinib treatment. As CML is a rare disease in ...

Background: Skull development is a tightly regulated process that occurs along the osteogenic interfaces of the cranial sutures that allow rapid bone formation at the edges of the bone fronts. Premature closure of cranial sutures can result in pathological conditions such as Craniosynostosis. The mechanosensory proteins Polycystin 1 (PC1) and 2 (PC2) have been shown to regulate skeletal development and potentially suture formation.Aim: The aim of study w...

Elevated levels of circulating serotonin have been reported to decrease bone mineral density1. Conversely, reduced serotonin (5HT) in mice lacking TPH1, the rate limiting enzyme for 5HT synthesis, was reported to be anabolic to the skeleton with high osteoblastic activity2. However, in other studies TPH1 deletion led to either an initial increase in BMD due to inhibition of osteoclastic bone resorption3, or had no bone effect4</su...

Background: Surgical treatment of type 2 diabetes, specially in obese patients, has provided good results in the control of blood glucose and Hb1Ac although its effect on bone health is not clear. The aim of this study was to evaluate gene expression of bone remodelling markers in type 2 diabetic Goto-Kakizaki (GK) non-obese rats after gastrojejunal bypass and sleeve gastroplasty, and their relationship with hormonal parameters.Materials and methods: We ...

Denosumab subcutaneous administration every 6 months reduced the incidence of new fractures in postmenopausal women with osteoporosis by 68% at the spine and 40% at the hip over 36 months compared with placebo in the FREEDOM study (Cummings et al., NEJM, 2009:361:756). This efficacy was supported by differential improvements from baseline in vertebral and femoral strength at 36 months (18.2 and 8.6%, respectively) estimated by an established voxel-based finit...