Morinda officinalis polysaccharide enhances osteogenic differentiation and migration of bone marrow mesenchymal cells by activating P38MAPK signal transduction.

Morinda officinalis polysaccharide (MOP), a derivative extracted from the traditional Chinese medicine Morinda officinalis, exhibits immunomodulatory and anti-osteoporosis (OP) effects. However, the mechanism underlying MOP's promotion of bone mesenchymal stem cell (BMSC) osteogenic differentiation remains unclear. Flow cytometry was employed to characterize BMSCs isolated from SD rats. The biological characteristics of BMSCs were detected using methyl thiazolyl tetrazolium (MTT), scratch healing, and colony formation assays. To assess the effect of MOP on BMSC osteogenic differentiation, Alizarin Red S staining and alkaline phosphatase (ALP) activity assays were performed. Osteogenic-associated proteins and gene expression were measured by western blot and RT-qPCR. MOP (40 μg/mL) promoted BMSC proliferation, enhanced colony formation and migration, promoted the formation of mineralized nodules of BMSCs, and increased ALP activity. Moreover, MOP treatment upregulated osteoblast-related protein and gene levels. In addition, MOP activated the P38 MAPK signaling pathway, and the addition of p38 pathway inhibitor SB203580 inhibited cell viability, colony formation, migration, and osteogenic differentiation of BMSCs. These findings suggest that MOP enhances BMSC proliferation and migration through P38 MAPK pathway activation, thereby promoting osteogenic differentiation.