Bone Abstracts

Bone resorption and deposition occur in a tightly regulated fashion reflecting the coupled activities of osteoclasts and osteoblasts. Several pathological conditions perturb this balance between bone synthesis and resorption, including osteoporosis and skeletal metastases. The uncoupling of remodeling activities contributes to disseminated tumor cells homing to the bone and to tumor growth in bone. Therefore, a reliable marker of bone remodeling would be useful to provide a st...

Bone resorption and formation occur in a tightly regulated fashion reflecting the coupled activities of osteoclasts and osteoblasts. Several pathological conditions perturb this balance, including osteoporosis and skeletal metastases. In the case of metastases, the uncoupling of resorption and formation activities contributes to disseminated tumor cells homing to the bone and to tumor growth within the bone in highly localized regions. Therefore, a site-specific marker of bone...

The maintenance and adaptation of bone morphology results from orchestrated remodeling processes. These processes are locally coordinated by osteocytes with biochemical signals that result in increased or decreased bone formation or resorption activities. To better understand the morphology, we therefore have to understand how osteocytes determine dynamic morphometric parameters within their local microenvironment. Recently, a local in vivo environment (LivE)...

ASARM peptide (acidic, serine- and aspartate-rich motif) and osteopontin (OPN) fragments accumulate in X-linked hypophosphatemia patients and/or in the Hyp mouse model and, when phosphorylated, potently inhibit mineralization in osteoblast cultures. To investigate this inhibition, we modeled the binding to hydroxyapatite of the human OPN-ASARM peptide (DDSHQSDESHHSDESDEL) using RosettaSurface computational simulations. Peptide binding to hydroxyapatite atomic planes constructe...

Introduction: Standard clinical treatments for postmenopausal osteoporosis utilize resorption-inhibiting drugs such as bisphosphonates, which selectively bind to bone mineral but also suppress bone formation over time. Prostaglandin E2 (PGE2) has bone-anabolic effects in vivo, but its clinical utility is hindered by side effects upon systemic administration. Since PGE2 acts on bone via the EP4 receptor, our approach utilizes a specific...

Children with chronic medical conditions are at increased risk for bone fragility from multiple mechanisms, related both to the underlying condition and its treatment, in particular glucocorticoids. The differential effects of the underlying medical disease on bone micro-architecture have not been well elucidated.Objectives: To describe the bone micro-architectural characteristics in children with rheumatic and oncological disorders treated with glucocor...

Sclerostin, a Wnt signaling antagonist encoded by the SOST gene, negatively regulates osteoblasts and inhibits bone formation. Mechanical loading, which induces bone formation, leads to a decrease in sclerostin levels. Recently, neutralizing antibodies against sclerostin were tested successfully for the treatment of osteoporosis in rodents. However, sclerostin is not the only signal involved in mechanotransduction. Therefore we investigated whether treatment with sclerostin an...

Peripheral quantitative computed tomography (pQCT) is receiving considerable attention in the diagnosis and monitoring of human bone diseases. It is well accepted that lower image resolution compared to micro-computed tomography (micro-CT) affects bone morphometry. With advances in micro-CT evaluation techniques such as sample-specific remodeling simulations or dynamic bone morphometry, there is the potential to also allow the application of such techniques to clinical pQCT sc...

Silk fibroin (SF) sponges are a promising scaffold material for tissue engineering due to their biocompatibility, mechanical properties, and ability to support calcium-phosphate formation in vitro. However, previous studies have shown that SF can mineralize spontaneously in the presence of culture media, which has a detrimental effect on experimental integrity when analyzing how cells deposit bone-like tissue in tissue engineering studies. In this study we analyzed th...

Osteoporosis is an age related disease characterised by a progressive decrease of bone mineral density and loss of bone quality. Twin studies show that genetic component contributes up to 85% of the BMD variability of population. Surprisingly little variability of BMD can be explained by genetic polymorphisms (~2.9%). This highlights the complex genetic architecture and suggests that many other molecular processes and genes have to be involved. Our previous research showed tha...