Potential therapeutic implications of Pim1 inhibitor SGI-1776 in bone loss disorders 3483

Abstract Description Pim1, a serine/threonine kinase, has emerged as a potential regulator in various cellular processes. However, its role in osteoclast function and bone homeostasis remains largely unexplored. This study aimed to investigate the role of Pim1 in osteoclast activity and bone metabolism using both in vitro and in vivo approaches. In vitro experiments were conducted using primary mouse bone marrow-derived monocyte/macrophages (BMMs). Treatment with SGI-1776, a selective Pim1 inhibitor, did not affect osteoclast differentiation. However, SGI-1776 significantly reduced the resorption activity of mature osteoclasts, as evidenced by decreased pit formation. Further investigation revealed that SGI-1776 impaired actin ring formation, a critical structure for osteoclast function, suggesting a role for Pim1 in cytoskeletal organization of osteoclasts. To validate these findings in vivo, we employed a lipopolysaccharide (LPS)-induced bone resorption model in mice. SGI-1776 significantly attenuated inflammatory bone destruction, as assessed by histomorphometry. This protective effect was associated with reduced osteoclast activity rather than a decrease in osteoclast numbers, consistent with our in vitro observations. In conclusion, these findings suggest that Pim1 inhibition could be a potential therapeutic strategy for bone loss disorders, warranting further investigation into its clinical applications in diseases such as osteoporosis and rheumatoid arthritis. Topic Categories Innate Immune Responses and Host Defense: Cellular Mechanisms (INC)