GLP-1RA in JBMMSCs promoted osteogenic differentiation via modulating CREB and BRD4 signaling mediated proliferation and stemness.

This study aims to examine the molecular mechanisms underlying the curative effects of jaw bone marrow mesenchymal stem cells (JBMMSCs) on rat mandibular osteoporosis following semaglutide administration. We acquired data from rats with osteoporosis via the GEO database for bioinformatics analysis. JBMMSCs (Jaw Bone Marrow Mesenchymal Stem Cells) were then isolated from rat mandibles and characterized via flow cytometry. To evaluate the therapeutic effect of semaglutide on osteoporosis following JBMMSC intervention in osteoporotic rat models, we employed Haematoxylin and eosin (HE) staining. In vitro, the ideal semaglutide concentration for JBMMSC osteogenic induction was established using CCK-8 viability, colony formation, and scratch migration assays. JBMMSCs were subsequently injected into the tail vein for osteoporosis treatment. Protein expression related to adipogenic and osteogenic differentiation pathways was assessed by Western blotting. Furthermore, we evaluated the osteogenic (using ALP and ARS staining) and adipogenic (using Oil Red O staining) differentiation potential of JBMMSCs. Finally, to elucidate the molecular mechanisms underlying semaglutide's treatment of osteoporosis mediated by JBMMSCs, we analyzed the protein levels of key signaling molecules including p-CREB, YAP, BRD4; pluripotency factors OCT4, SOX2, c-Myc; cell cycle regulator Cyclin D1; signaling mediators p-STAT3, TET3, SHP2, p-SMAD1/5; and osteogenic transcription factors β-Catenin, RUNX2, DLX5. HE staining revealed that JBMMSC intervention combined with semaglutide significantly ameliorated osteoporosis in rats. Alizarin Red S and ALP staining further indicated a marked elevation in calcified nodule formation and ALP activity following semaglutide treatment, demonstrating optimal osteogenic potential in JBMMSCs. Immunofluorescence analysis confirmed elevated expression of stemness-associated proteins in these cells. Furthermore, CCK-8 and colony formation assays indicated that semaglutide stimulated JBMMSC proliferation and stemness maintenance. Western blot analysis detected a significant upregulation of p-CREB, OCT4, BMP2, and RUNX2 protein expression in JBMMSCs treated with semaglutide. Mechanistically, semaglutide corrected osteoporosis through dual pathways: promoting osteogenic and adipogenic differentiation via the BMP2/STAT3/TET3/SHP2 axis, and preserving bone marrow mesenchymal stem cell stemness via the CREB/YAP/BRD4 axis. These mechanistic insights were validated by rescue experiments. GLP-1 receptor agonists (GLP-1RAs) enhance osteogenic differentiation of jaw bone marrow mesenchymal stem cells (JBMMSCs) through modulation of the CREB/YAP/STAT3/BRD4 signaling axis. This pathway activation potentiates cellular proliferation and stemness maintenance, suggesting a promising therapeutic strategy for osteoporosis intervention.