摘要Objective This study aimed to investigate the effect of Astragalus(AST)on osteoporosis(OP)and the downstream mechanisms.Methods Human bone marrow-derived mesenchymal stem cells(hBMSCs)were induced to differentiate into osteogenic cells.After transfection with relevant plasmids,cell proliferation,cell cycle progression,and apoptosis were assessed.Alizarin red staining was used to detect calcium nodules in the cells,alkaline phosphatase(ALP)staining was used to detect ALP activity in the cells,and quantitative reverse transcription-polymerase chain reaction and western blotting were used to determine RUNX2 and Osterix expression levels.An OP rat model was established using ovariectomy and micro-computed tomography scanning.Hematoxylin and eosin staining and Masson's trichrome staining were used to evaluate the pathological conditions of bone tissues,while immunohistochemistry was conducted to detect RUNX2 in bone tissues.Results AST promoted the osteogenic differentiation of BMSCs,reduced miR-181d-5p expression levels,and increased SOX11 expression levels.Restoring miR-181d-5p expression or reducing SOX11 expression levels reversed the effects of AST on the osteogenic differentiation of hBMSCs.miR-181d-5p was found to target SOX11 in hBMSCs.AST improved OP in rats,and miR-181d-5p overexpression or SOX11 inhibition reversed the therapeutic effects of AST on OP in rats.Conclusion AST promoted the osteogenic differentiation of hBMSCs and alleviated OP by targeting SOX11 via miR-181d-5p.