Background and Objective: Mobilization of Hematopoietic Stem Cells (HSCs) for transplantation and the importance of -adrenergic signals in induction of this process have been well investigated. However, little is known about the role of -adrenergic signals in mobilization of HSCs and factors influenced by these signals. The Chemokine Stromal Derived Factor -1 (SDF-1) which is expressed by human bone marrow-derived mesenchymal stem cells (hMSCs), has a key role in mobilization of HSCs. In addition, miR-886-3p and miR-23a can regulate the expression of SDF-1 in hMSCs. In this study, to investigate the role of miR-886-3p and miR-23a in mobilization process, expression of both miRNAs was evaluated in hMSCs treated by Isoproterenol (a -adrenergic agonist). Materials and Methods: hMSCs were isolated from human bone marrow and cultured. Following flowcytometric analysis, the cells were treated with 100 M isoproterenol. Total RNA was extracted at 12 and 48 hours post treatment, and also from untreated hMSCs as control. Then, miR-886-3p and miR-23a expression levels were quantified by quantitative Reverse Transcriptase PCR. Results: The expression level of miR-886-3p increased significantly at 12 and 48 hours post treatment (P<0.05). In addition, the expression level of miR-23a decreased at 12 hours post treatment and increased significantly at 48 hours post treatment (P<0.05). Conclusion: Isoproterenol induces miR-886-3p in hMSCs. MiR-23a is primarily decreased, and then increased due to treating with isoproterenol. So both miRNAs can contribute to mobilization process. References 1- Horowitz MM, Gale RP, Sondel PM, et al. Graft-versus-leukemia reactions after bone marrow transplantation. Blood. 1990 75: 555-62. 2- Sykes M, Nikolic B. Treatment of severe autoimmune disease by stem-cell transplantation. Nature. 2005 435: 620-7. 3- Copelan EA. Hematopoietic stem-cell transplantation. 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