Bone Abstracts

We have reported femoral osteopenia in short term-vitamin D restricted rats without deterioration in tibial cortical bone volume (CBV), geometry or strength1. This study aimed to establish the effect of extended vitamin D deficiency in aged rat tibial volume and strength. Female Sprague-Dawley rats (9 m, n=6/group) were fed a diet containing varying vitamin D3 (D) levels (0, 2, 12, and 20 IU/day) with either low (0.1%, LCa) or high (1%, HCa) diet...

Recent studies confirmed the role of WNT16 in bone mineral density (BMD), bone strength and fracture risk. These findings made WNT16 interesting for further genetic and functional studies to clarify its effect on osteoporosis related parameters.A WNT16 candidate gene association study was performed in men from the Odense Androgen Study (OAS). Five tagSNPs and one multimarker test were selected for genotyping to cover most of th...

It is still unknown where from osteoblasts are recruited during remodeling of adult human cancellous bone. Still, it is often suggested that they originate from perivascular osteoprogenitors in the bone marrow (BM). Here we propose also the existence of a layer of osteoprogenitors at the periphery of the BM. This proposal is based on electron and light microscopy of the bone surface and of the neighboring BM in human iliac crest biopsies, where we quantified cell densities, ce...

Background: Sun exposure may be limited in Arctic populations and Greenland Inuit have adapted to the Arctic environment. The influence of chronic low vitamin D level on PTH to uphold a normal serum calcium remains to be elucidated.Objective: To describe the association between PTH and factors known to influence PTH-, including vitamin D (25OHD) and calcium, in Arctic populations.Methods: Inuit and non-Inuit in the capital city Nuu...

We have shown that the bisphosphonate pamidronate (P) given to children <10d post-burn prevents resorptive bone loss and muscle protein breakdown. We have also shown in vitro that Ca modulates the inflammatory response by altering mononuclear cell chemokine production. We hypothesized that P affects muscle protein breakdown by altering cytokine or chemokine concentration directly or indirectly by lowering blood ionized (i) Ca. We retrospectively analysed biomarker...

Background: The traditional Inuit diet in Greenland consists mainly of fish and marine mammals. The marine diet is an important source for vitamin D in Greenland. Vitamin D has anti-inflammatory capacity but markers of inflammation were high in Inuit with a high intake of marine food items. Yet, the effect of vitamin D on inflammation in Inuit remains unsettled.Objectives: To investigate the association between vitamin D and markers of inflammation in a ...

Objectives: Spinal muscular atrophy (SMA) results in varying degrees of hypotonic immobility. Prior reports demonstrate an increased risk of fracture and a trend toward low bone mineral density (BMD) in this population. We aim to further characterize bone health in paediatric SMA patients by reporting the prevalence of fractures and low BMD (z-score≤−2.0) by SMA subtype, BMD of the lateral distal femur (LDF; an important fracture location in non-ambulatory...

Introduction: Aromatase inhibitors (AI) used as adjuvant treatment of hormone-sensitive breast cancer reduce the level of circulating estrogen and cause accelerated bone loss. The aim of this study is to investigate the prevalence of osteoporosis in women with breast cancer and the effect of chemotherapy on the risk of osteoporosis.Methods: Three hundred and sixty women with hormone-sensitive breast cancer who were scheduled to start treatment with AI we...

The R-spondins are a family of four small, secreted agonists of the Wnt signaling pathway. Growing evidence from both in vitro studies and in vivo models supports the major role of these proteins in the skeletal development processes. In humans, common genetic variation in the RSPO3 gene has been associated with BMD in large scale GWAS study.This study aimed at further investigation of the genetic and functional contributions of the R-s...

Bone sialoprotein regulates osteoblast activity and bone formation. In knockout (BSP−/−) mouse bone marrow (BM) stromal cell cultures, the pool of osteoprogenitor (OP) cells (CFU-F number) is not different from wild-type (+/+), nor is their early differentiation (same numbers of alkaline phosphatase positive colonies=CFU-ALP, although these are smaller), while the number of osteoblast, mineralized colonies (CFU-OB) is dramatically reduced. Because ossifi...