Abstract: Objective To investigate the effect of adipose stem cells-derived exosomes ( ADSCs-Exo) on osteogenic differentiation of periodontal ligament stem cells ( PDLSCs) through themiR-654-3p pathway. Methods Human ADSCs were isolated, identified, and cultured in vitro,and exosomes were isolated. Human PDLSCs were isolated in vitro, and the miR-654-3p inhibitor orits negative control (inhibitor NC) were transferred into cells, and cultured with or without a combined osteogenic induction solution. Cells were divided into 6 groups: Blank group, ADSCs-Exogroup, inhibitor NC group, inhibitor NC + ADSCs-Exo group, miR-654-3p inhibitor group, miR-654-3p inhibitor + ADSCs-Exo group. After 7 days of induction, the expression levels of miR-654-3p, osteocalcin ( OCN) and typeⅠ collagen ( COL1A1) mRNA in cells were detected by RTqPCR, and ALP activity was detected in cells by alkaline phosphatase (ALP) activity kit. After 21days of induction, the alizarin red staining method was used to detect the calcium nodules’ formation ability of cells, and the expression levels of OCN and COL1A1 protein were detected by West ern blotting. Results Compared with those in the Blank group or inhibitor NC group, the expression level of miR-654-3p, the activity of ALP, the expression levels of OCN and COL1A1 mRNAand protein in the ADSCs-Exo group were increased (P< 0. 05), and the formation ability of calcium nodules was enhanced (P < 0. 05), and the expression level of miR-654-3p was decreased inthe miR-654-3p inhibitor group. Compared with those in the inhibitor NC + ADSCs-Exo group, the ALP activity, the expression levels of OCN and COL1A1 mRNA and protein in the miR-654-3p inhibitor + ADSCs-Exo group were decreased (P < 0. 05), and the formation ability of calcium nodules was decreased ( P < 0. 05 ). Conclusion ADSCs-Exo promote osteogenic differentiation of
PDLSCs by up-regulating the expression of miR-654-3p.

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