Salvianolic acid B mitigates senescence and promotes osteogenesis of senescent bone marrow mesenchymal stem cells via the PI3K/AKT pathway

Senescence is a major contributor to osteoporosis, with progressive bone loss in later life characterizing age-related osteoporosis. The decline in bone marrow mesenchymal stem cells (BMSCs) function, particularly the reduction in osteogenic capacity, plays a central role in this process. Therefore, improving the function of senescent BMSCs could potentially slow the age-related osteoporosis progression. Salvianolic acid B (Sal-B), the most abundant and bioactive water-soluble compound derived from the traditional herb Salvia miltiorrhiza and growing evidence supports its efficacy against osteoporosis. However, the underlying cellular and molecular mechanisms remain unclear. This study aimed to investigate the effects and mechanisms of Sal-B on senescent BMSCs in vitro. Our study show that Sal-B not only promoted osteogenic differentiation but also attenuated cellular senescence in senescent BMSCs. Mechanistically, the PI3K/Akt pathway played a crucial role in mediating these beneficial effects. These findings clarify the biological action and mechanism of Sal-B at the cellular level, providing a theoretical foundation for subsequent in vivo studies.