Bone Abstracts

Destruction of the articular cartilage is the major feature of Osteoarthritis (OA). Ageing is the primary risk factor, but how ageing results in OA is still an enigma. In OA, articular chondrocytes degrade their own matrix, while in healthy articular cartilage they preserve it.Transforming growth factor β (TGFβ) is a central regulator of chondrocyte proliferation, differentiation and extracellular matrix production. Deregulation of TGFβ si...

Total hip arthroplasty (THA) is the treatment for severe hip osteoarthritis. It improves the quality of life, pain and patient autonomy. However, a periprosthetic resorption may occur, in 3–5% of patients after 10 years of the primary surgery requiring implant replacement. Bisphosphonates (BP), inhibitors of bone resorption, represent a potential candidate for modulating periprosthetic bone loss. Randomized controlled trials have also suggested that BP could prevent early...

Nacre, or mother of pearl, is a promising natural biocompatible biomaterial consisting of aragonite (97%) and of organics (3%) and capable to increase the cell osteogenic activity. It has been established that osteoarthritic osteoblasts present a mineralization defect and, to date, only a few molecules (vitamin D3 and bone morphogenetic protein2) could improve the mineralization potential of this cell type. In this context, we evaluated the impact of nacreous molecules on the ...

Vascular calcification has a marked impact on arterial heterogeneity and plaque stability. Based on a cohort of 116 patients (carotid and femoral endarterectomies), the aim of the present study was to determine the influence of the bone-like vascular calcification and of osteoprotegerin (OPG) on plaque stability.Seventy-three carotid and 43 femoral plaques along with plasma were harvested and analyzed in a single center study. The presence of osteoid met...

Cherubism is a rare genetic disorder characterized by extensive growth of a bilateral granuloma of the jaws, resulting in facial disfigurement.Histologically, the lesions consist of a fibrotic stroma with osteoclastic-like multinuclear giant cells (MGC). Cherubism is caused by gain-of-function mutations in the SH3BP2 protein. SH3BP2 is an intracellular adaptor protein positively regulating the activity of the nuclear factor of activated T-cells c1 (NFATc...

Nacre is able to induce bone-forming cells mineralization, and gains widespread interest in bone regeneration. While, the osteoinductive compounds are not identified yet. The nacre extract, ethanol soluble matrix (ESM), was proven having the capacity to induce the mineralization of mouse MC3T3-E1 cells and to restore mineralization defect in human osteoarthritic osteoblasts. Being tested on the two cells, ESM could induce the formation of mineralization nodules, identified as ...

Chondrosarcomas are cartilage-forming, poorly vascularized tumors. With an estimated annual incidence of 1 in 200 000, they represent the second malignant primary bone tumor of adults after osteosarcoma. These tumors are resistant to chemotherapy and radiotherapy, surgical excision remaining the only therapeutic option. However, very few cell lines and animal models are available, and the mechanisms behind their chemoresistance remain largely unknown. Our goal was to establish...

Estrogens are important regulators of bone mass and exert their physiological effects on bone mainly via estrogen receptor α (ERα). Central ERα has been reported to exert an inhibitory role on bone mass. ERα is widely distributed in the brain with a high expression in the arcuate nucleus (ARC) and the ventral medial nucleus (VMN) in the hypothalamus. Here, we tested the hypothesis that ERα in hypothalamic pro-opiomelanocortin (POMC) neurons, located in...

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It is well established that estrogen, mainly via estrogen receptor alpha (ERα), has positive effects on bone, but estrogen is not considered as a treatment option against osteoporosis due to negative side-effects in other tissues. ERα is widely subjected to posttranslational modifications (PTMs), which can affect cellular responses to estrogen in a tissue specific manner by influencing the function of ERα and its interactions with other proteins. The in vivo...