Searchable abstracts of presentations at key conferences on calcified tissues

ba0003pp123 | Cell biology: osteoblasts and bone formation | ECTS2014

miR-468 controls Runx2 expression during early differentiation of Runx2 in mice

Cabon Owen , Geoffroy Valerie

We investigated the ability of microRNAs to regulate osteoblast differentiation by controlling distinct aspects of the differentiation process. We have identified by microRNAs microarray a set of miRNAs that are differentially regulated during differentiation of the two osteoblast cell lines MC3T3-E1 and C3H10T1/2. We focused on miR-468 that is a potential regulator of Runx2.In our microarray analysis miR-468 was expressed at a high level and was strongl...

ba0003pp151 | Cell biology: osteoblasts and bone formation | ECTS2014

Syndecan-2 is a new negative modulator of Wnt signaling within bone marrow

Mansouri Rafik , Geoffroy Valerie , Marie Pierre , Modrowski Dominique

Wnt factors bind to heparan sulfate chains of syndecans that hence control their distribution in the cell microenvironment and also contribute to the internalization and recycling of the Wnt receptors. Syndecans are therefore likely important Wnt regulators within the bone marrow. Here, we investigated the interactions between Syndecan-2 and Wnt signaling in normal bone cells. We analyzed the effects of 2.3 kb Col1A1 promoter-driven Syndecan-2 overexpression in osteoblasts. Sy...

ba0005p249 | Genetics and Epigenetics | ECTS2016

Identification of epigenomic regulators of osteoblast function

Henaff Carole Le , Partridge Nicola , Jehan Frederic , Geoffroy Valerie

Molecularly characterized epigenetic networks that control bone formation and are altered during aging are necessary to uncover new potential targets for osteoanabolic therapy. Our contribution to the iBONE consortium is to identify osteoanabolic epigenomic regulators by screening which are involved in osteoblast phenotype and differentiation. This study will be done by a 3 step approach including: siRNA screening for epigenomic regulators of osteoblastic differentiation and v...

ba0001pp17 | Arthritis and other joint diseases: translational and clinical | ECTS2013

Bone is the main target of activation of Canonical Wnt pathway in osteoarthritis

Funck-Brentano Thomas , Bouaziz Wafa , Geoffroy Valerie , Hannouche Didier , Marty Caroline , Hay Eric , Cohen-Solal Martine

Objective: Wnt/β-catenin pathway is a main regulator of bone remodeling, but might be inhibited in cartilage in osteoarthritis (OA). We here investigated the effect of mechanical loading in Wnt activation and the expression of Wnt antagonists in the joint tissues.Methods: Topgal mice were used. Mice underwent partial meniscectomy (Mnx) and sacrificed at 4, 6, and 9 weeks. Dissected knees were scanned by microCT and then prepared for cryosectioning t...

ba0003pp15 | Arthritis and other joint diseases: translational and clinical | ECTS2014

Bone secreted dickkopf-related protein 1 ameliorates osteoarthritis in mice

Funck-Brentano Thomas , Bouaziz Wafa , Marty Caroline , Geoffroy Valerie , Hay Eric , Cohen-Solal Martine

Objective: Cartilage loss and subchondral bone changes are hallmarks of osteoarthritis (OA). The Wnt family is involved in the regulation of bone and cartilage. We have shown that the Wnt/β-catenin pathway is activated in bone during OA, but the effect of its inhibition in bone in cartilage remodeling is unknown. We here investigated the impact of the bone-specific inhibition of Wnt during the development of OA.Methods: Partial meniscectomy (Mnx) wa...

ba0003pp288 | Osteoporosis: pathophysiology and epidemiology | ECTS2014

Decrease in expression of MMP3 in osteoblast protects against bone loss

Zarka-Prost-Dumont Mylene , Jehan Frederic , Ostertag Agnes , de Vernejoul Marie-Christine , Geoffroy Valerie

Osteoblastic MMPs are important actors of bone remodeling. We showed previously that osteoblast specific overexpression of TIMP1, an inhibitor of MMPs, prevents the bone loss induced by ovariectomy mainly through inhibition of bone resorption. We hypothesized that inhibition of the MMP3 could be implicated in the protective effect of TIMP1 and that MMP3 polymorphisms located in the proximal promoter of MMP3 gene could be associated to post-menopausal bone loss in women.<p ...