Bone Abstracts

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...

It has long been known that osteoarthritis induces dramatic structural changes in subchondral bone. Studies on patients’ biopsies have also shown that the new sclerotic bone is hypomineralized and has decreased elastic modulus. Due to their amenability for genetic studies, murine models of OA are particularly important for drug target discovery. However, whilst osteosclerosis has been reported also in murine OA models, little is known about the compositional and mechanica...

Background: Osteoclasts are unique multinucleated cells that originate from the fusion of monocytes. They are the only cells known to be capable of bone resorption. Interestingly, the foreign body multinucleated giant cell (FBGC) arises from the same lineage as the osteoclast, and they share numerous similar characteristics, among which the expression of tartrate resistant acid phosphatase (TRAcP). Yet, it is not known whether the FBGC has the capacity to resorb bone.<p cl...

Ageing is universally linked to skeletal deterioration. Common mechanisms may control both processes, where dysregulation may predispose to bone loss and osteoarthritis (OA). The epigenetic modifier SirT1 controls lifespan and decreases with age. However, the role of SirT1 in joint disease is unclear. Human tissue samples, novel genetically modified mice, a surgical disease model and advanced cellular and molecular studies were employed to explore the hypothesis that SirT1 is ...

Osteoclasts are multinucleated bone-resorbing cells and can be cultured from different monocytic precursors. It is unknown whether osteoclasts derived from different precursors are phenotypically different. One of the aspects not known is the life span of the different osteoclasts and the effect of IL-1β hereupon. Here, we studied this using time-lapse microscopy. Bone marrow cells were isolated from 6-week-old male mice. Early blasts (CD31hiLy-6C-),...

Background: Osteoclasts (OCs) are bone-degrading cells that differentiate from the monocyte/macrophage lineage. In human, three monocyte subsets have been identified: classical, intermediate and non-classical monocytes. We have previously demonstrated that comparable numbers of OCs can be generated from these subsets on plastic, but that the number of OCs significantly differs when the monocytes are cultured on bone. It is plausible that the observed differences are associated...

Aim: Lean mass is a strong determinant of bone structure, particularly during growth and development. We sought to determine if there are sex differences in bone acquisition in pre-pubertal children and the potential relation with skeletal loading.Methods: This study included 3602 children (50.7% girls) whose total body BMD and hip scans were measured on the same iDXA devise (GE-Lunar) at 6 years of age. Hip scans underwent hip structural analysis (HSA) ...

Fibrodysplasia ossificans progressiva (FOP) is a rare debilitating genetic disease characterized by abnormal progressive heterotopic endochondrial ossification of soft tissues. FOP results from mutations in the intracellular domain of the type I BMP receptor ACVR1 (ALK2) the most common of which is R206H. FOP mutations alter the sensitivity of ACVR1 to Activin A from an antagonist to an agonist. We have previously shown that Activin A is necessary and sufficient for driving he...

Objectives: Previous studies indicate that about half of boys and one fourth of girls suffer a fracture before the age of 16 years. Similarly, children of European descent are more prone to fracture. Here we aimed to investigate at the population level the influence of sex, ethnic background and bone mineral density (BMD) on the occurrence of bone fractures in children of school age.Methods: This study (n=3,633 children with complete information...

Background: Low total body BMD (TB-BMD) is an established risk factor for fractures in healthy children. However, bone strength depends not only on bone mass and density, but also on the structural geometry of bones. Hip structural analysis (HSA) is a technique applied on hip DXA scans to calculate several bone geometry parameters. The aim of our study was to evaluate other bone geometrical parameters that can constitute determinants of fracture risk. Specifically, we examined...