Abstract:Objective To study the regulation of a disintegrin and metalloproteinase 10 (ADAM10) gene on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and tibial fracture union. Methods BMSCs of SD rats were cultured, BMSCs stably transfected with negative control (NC) shRNA or ADAM10 shRNA pGFP-V-RS vector were established, the osteogenesis was induced for 14 days. During the induction process, DMSO or 10 μmol/L Notch1 agonist valproic acid (VPA) were added. absorbance at 405nm of alizarin red staining, ALP activity and the expression levels of ADAM10, OCN, Runx2, CoL-I, NICD and Hes1 were detected. The tibial fracture model of SD rats was established and NC shRNA or ADAM10 shRNA pCMV5.0 vector was injected locally. The fracture healing and gene expression were observed for 4 weeks later. Results The expression level of ADAM10 in BMSCs in sh-ADAM10 group was lower than that in sh-NC group. After osteogenesis induction, the absorbance value of alizarin red staining at 405nm, ALP activity and the expression levels of OCN, Runx2, CoL-I, NICD and Hes1 of sh-ADAM10 group were higher than those in sh-NC group (P<0.05). the absorbance value of alizarin red staining at 405nm, ALP activity and the expression levels of OCN, Runx2, CoL-I of sh-ADAM10 VPA group after osteogenesis induction were lower than those in sh-ADAM DMSO group (P < 0.05). The fracture healing of tibial fracture rats in sh-ADAM10 group was better than that in sh-NC group, and the expression levels of OCN, Runx2, CoL-I, NICD and Hes1 were higher than those in sh-NC group (P<0.05). Conclusion Knockdown of ADAM10 can promote the osteogenic differentiation of BMSCs and the healing of tibial fractures by inhibiting Notch1 pathway.