Bone Abstracts

Several cell types form the hematopoietic stem cell niche. These niches sometimes become hijacked by cancer cells, which may later form metastatic lesions. Our aim was therefore to characterize the bone marrow microenvironment to affect cancer cell homing to bone marrow.Pharmacologic modification consisting of PTH to stimulate the osteoblasts and zoledronic acid to prevent the increase in osteoclasts through PTH resulted in increased homing of cancer cel...

The relationship between bone formation and blood flow is unclear. Recently, PTH was reported to activate production of nitric oxide (NO), a potent vasorelaxing agent, in endothelial cells and we and others have confirmed a strong vasorelaxing action of PTH in vivo in the mouse. Here, we tested the hypothesis that a potent NO synthase inhibitor (L-NAME: NG-nitro-L-arginine methyl ester) may alter the effect of intermittent PTH (iPTH) on b...

Previous studies have demonstrated that patients with osteoporosis (OP) have a poor understanding of their bone disease and that this negatively influences treatment decisions and medication compliance. The aim of this study is to determine if there is a discrepancy between perceived and objective disease knowledge (PK and OK, respectively) in patients with OP and whether this correlates with certain patient characteristics.Design and methods: After ethi...

Hypophosphatasia (HPP) is a rare disease characterized by low enzymatic activity of tissue-nonspecific alkaline phosphatase (TNSALP) resulting in an accumulation of its endogenous substrates like pyridoxal phosphate (PLP) and inorganic pyrophosphate (PPi). The ectoenzyme plays an important role during bone mineralization and might contribute to proper function of kidney and muscle. Neurological symptoms of HPP like seizures, anxiety disorders and depression provide ...

Fractures in children are common; prospective cohort studies suggest narrower bones predispose to fracture. Early life events can influence later growth and development. Observational studies suggest children born to mothers with lower vitamin D levels during pregnancy have narrower bones. We investigated the effects of maternal vitamin D deficiency on offspring’s bones’ response to mechanical loading in a model system.C57BL/6 female mice (...

Osteoblasts line the inner surface of the bone and are located in close proximity to the bone marrow, where hematopoiesis takes place. Osteoblasts produce several cytokines that affect various steps of hematopoiesis, and produce fibronectin isoforms that affect cell differentiation. Little is known however on whether osteoblasts modulate the immune response. Our aim was to evaluate the role of fibronectin originating from the osteoblasts on hematopoiesis and the immune respons...

Type 2 diabetes mellitus prevalence increases with age and the disease predisposes to increased risk of fractures and skeletal complications. One possible contributor to skeletal weakening in diabetes is a decline in blood supply. We hypothesised that bone blood flow is impaired in diabetic mice and that chronic administration of glucagon-like peptide-1 receptor agonists (GLP-1RA) can increase blood flow to bone, thereby stimulating bone formation and improving bone architectu...

Anorexia nervosa (AN) a condition of profound undernutrition, is characterized by alterations in neuroendocrine and metabolic functions. Among the serious pathological consequences of this eating disorder, osteoporosis is often observed and persists after recovery, leading to a high fracture risk.To study particularly bone alterations and recovery, a long term mouse model has been developed. In this model named separation-based anorexia (SBA) – a ch...

Beside the bone mass, structural changes are important determinants of the bone strength. Patients with osteoarthritis (OA) seem protected against femoral neck (FN) fracture. When compared to osteoporosis, FN in OA are characterized by a higher bone mass and a better trabecular microarchitecture (Blain et al., 2008, Boutroy et al., 2011). The presence of microcracks is one of the determinants of the bone strength. The aim of this study was to evaluate the mic...

Fractures in infancy raise the spectre of child abuse; it has been suggested that lack of vitamin D could result in bone abnormalities that could predispose to fractures. We utilised a mouse model system to investigate whether vitamin D deficiency in utero alters early bone growth and development.C57BL/6 female mice received vitamin D deficient or replete diet for 6 weeks, then mated and continued on their respective diets until weaning. Pups were culled...