Osteomodulin impacts positively the bone remodeling process in osteoarthritis

Purpose: Osteomodulin (OMD) is a Small Leucine Rich Proteoglycan (SLRP) highly specific of the bone extracellular matrix. Its production and expression are impaired in subchondral sclerosis associated with osteoarthritis (OA). This study aimed to investigate effects OMD on osteoblasts osteoclasts culture. Methods: Different concentrations (2.5, 10, 40 160 ng/ml), corresponding range concentration found supernatant primary vitro human osteoblast cultures, were tested sclerotic The from either or non-sclerotic area cortical OA patients isolated, serving as control. mineralization cultures was assessed Alizarin red staining at 17-day differentiation. To analyze effect osteoclasts, marrow mice harvested cells differentiated RANKL M-CSF into stopped 4-day osteoclast differentiation, (10 40ng/ml 5μg/ml) mixed M-CSF. number reported after TRAP staining. binding RANKL-OMD evaluated Solid Phase Binding Assay. In this test, coated Nickel plate, incubated OMD/RANKL complexes revealed polyclonal antibody. Results: No mortality observed tested. Sclerotic showed strong decrease comparison osteoblasts. partially restored (Fig. 1A). solid phase assay demonstrated ability bind RANKL. biological consequence murine Preliminary results pre-mix RANKL/M-CSF OMD, drastic it even fully blocked 5μg/ml 1B) Conclusions: major proteoglycan matrix turnover. It improves inhibits differentiation through capture content could trigger by initiating enhancing imbalance remodeling. research funded F.R.S.-FNRS for “EOS: Excellence Science -Join-t-against-Osteoarthritis”, grant 30480119 , Osteoarthritis Foundation www.osteoarthritisfoundation.eu .