Research Paper Volume 16, Issue 17 pp 12263—12276
Excessive glucocorticoids combined with RANKL promote the differentiation of bone marrow macrophages (BMM) into osteoclasts and accelerate the progression of osteoporosis by activating the SYK/SHP2/NF-κB signaling pathway
Figure 4. Modulation of osteoclastogenesis by the SYK/SHP2/NF-κB pathway. (A) Western blot analysis revealed decreased expression levels of NFATC1, c-fos, and Cathepsin K in GR inhibitor-treated BMM cells, with further reductions observed upon SYK inhibition and SHP2-KD. (B) Cell viability assay (CCK8) showed decreased optical density (OD) values in GR and SYK inhibitor-treated groups compared to controls, with a significant reduction in SHP2-KD cells. (C) Monoclonal formation assay demonstrated decreased colony formation in GR and SYK inhibitor-treated groups, with a further reduction in SHP2-KD cells. (D) Immunofluorescence staining for tartrate-resistant acid phosphatase (TRAP) indicated decreased fluorescence intensity in SHP2-KD, SYK inhibitor, and GR inhibitor-treated groups compared to controls, suggesting reduced presence of bone-resorbing cells. Abbreviations: SOP: Ovariectomized mice with osteoporosis; Non-SOP: Non-ovariectomized control mice; Lv-sh-SHP2: Lentivirus-mediated SHP2 knockdown; GR: Glucocorticoid receptor; BMM: Bone marrow-derived macrophages; OD: Optical density; NC: Negative control. **P < 0.01; nsP > 0.05.