AB0639 EXOSOMES DERIVED FROM ENDOTHELIAL CELLS PREVENT OSTEOBLAST APOPTOSIS IN STEROID-INDUCED OSTEONECROSIS OF THE FEMORAL HEAD RAT MODEL VIA THE PI3K/AKT/Bcl-2 SIGNAL PATHWAY

Background: Osteonecrosis of the femoral head (ONFH) is a common disease caused by many trauma factors and un-trauma factors. Among those factors, steroid-induced osteonecrosis (SNFH) accounted for large proportion mainly concentrated in young people. SNFH has been reported as an irreversible associated with damage blood vessels loss balance bone homeostasis. Circulating endothelial progenitor cells (CEPCs), one part circulating (CECs), are immature precursor proliferative potential. The vascular confirmed studies, but changes CECs CEPCs peripheral patients have not studied yet. Objectives: objective study to explore number normal people then investigate whether EC-secreted exosomes (EC-exos) could prevent progression rat model its mechanism action. Methods: We collect 3 heathy detected levels Flow cytometer. TEM, NTA western blot was used characterize isolated EC-exos. Annexin V-FITC/PI double staining flow cytometric analysis were evaluate MC3T3-E1 apoptosis. CCK-8, scratching experiment transwell viability migration ability. Micro-CT morphological progress model. Results: Firstly, we found that decreased than Then our results indicated EC-exos improve migration, apoptosis osteoblasts under dexamethasone activating PI3K/AKT/Bcl-2 signal pathway vitro. Finally, revealed prevented SNFH. Conclusion: enhance cell ability play anti-apoptosis role against steroids-induced osteoblast pathway. References: [1]Zalavras CG, Lieberman JR. head: evaluation treatment. J Am Acad Orthop Surg. 2014;22(7):455-64. [2]Microsurgery Department Orthopedics Branch Chinese Medical Doctor A, Group from O, Bone Defect Association R, Reconstructive S, Microsurgery, Surgery A. Guideline Diagnosis Treatment Femoral Head Adults. 2017;9(1):3-12. [3]Mont MA, Jones LC, Hungerford DS. Nontraumatic ten years later. Joint Surg Am. 2006;88(5):1117-32. [4]Yuan HF, Zhang J, Guo CA, Yan ZQ. Clinical outcomes after autologous marrow stem implantation: meta-analysis seven case-control studies. Clinics (Sao Paulo). 2016;71(2):110-3. [5]Houdek MT, Wyles CC, Packard BD, Terzic Behfar Sierra RJ. Decreased Osteogenic Activity Mesenchymal Stem Cells Patients With Corticosteroid-Induced Head. Arthroplasty. 2016;31(4):893-8. Disclosure Interests: None declared.