AB0030 OSTEOMODULIN DOWN-REGULATION IS ASSOCIATED WITH OSTEOARTHRITIS DEVELOPMENT

Background Osteoarthritis (OA) is associated with metabolic and structural changes in all joint tissues. Subchondral bone sclerosis, cartilage degradation, synovial inflammation are the main hallmarks of OA [1–3]. OMD a keratan sulfate proteoglycan, member small leucine-rich proteoglycan (SLRP) family. was first identified where it involved mineralization process [4,5]. Our previous work demonstrated that secretome osteoblasts, one most differentiating factors between osteoblasts originating from sclerotic non-sclerotic zone subchondral [3]. levels were lower supernatant coming area. Objectives The present examined if occurring during skeletal development OA. Methods We used Omd knock-out (KO) or overexpressing male mice mutant zebrafish to study vivo impact on aging. investigated influence severity damage induced by destabilization medial meniscus these mice. also analyzed animals’ gait using CatWalk XT system. effect gene expression human trabecular monolayer culture RNA sequencing method. Finally, binding RANKL assessed solid phase assay. Results In wild-type mice, we mainly calcified cartilage. Tibial growth plate significantly decreased genotypes age but lesser extent KO than other genotypes. layer thinner tibial plateau thicker lateral wild-type, while total thickness not different deficiency led less porous sclerosis. spontaneously developed more severe lesions contrast, production did median destabilization. pattern abnormal compared genotype shorter swing smaller paw contact intensity. omd -/- wild-type. culture, down-regulated some genes extracellular matrix organization up-regulated responsible for collagen network degradation. bound inhibited osteoclastogenesis. Conclusion Alterations modify metabolism structure. helps preserve integrity local decrease its leads increasing sclerosis thinning References [1]Maruotti N, Corrado A, Cantatore FP. Osteoblast role osteoarthritis pathogenesis. J Cell Physiol. 2017; 232 . doi:10.1002/jcp.25969 [2]Stewart HL, Kawcak CE. importance pathophysiology osteoarthritis. Front Vet Sci. 2018; 5 doi:10.3389/fvets.2018.00178 [3]Sanchez C, Mazzucchelli G, Lambert et al. Comparison derived versus OA: A pilot study. Published Online First: 2018. doi:10.1371/journal.pone.0194591 [4]Wendel M, Sommarin Y, Heinegård D. Characterization osteoadherin - novel, cell bone. Acta Orthop. 1995. doi:10.3109/17453679509157655 [5]Sommarin Wendel Shen Z, Osteoadherin, cell-binding bone, belongs family repeat proteins matrix. Journal Biological Chemistry 1998. doi:10.1074/jbc.273.27.16723 Acknowledgements: NIL. Disclosure Interests None Declared.