Morinda officinalis saponins promote osteogenic differentiation of human umbilical cord-derived mesenchymal stem cells via the BMP-SMAD signaling pathway.

Background: Morinda officinalis saponins (MOS), a traditional Chinese medicine extracted from M. officinalis roots, have been used as a health supplement. Existing evidence suggests that extracts from this plant can be used for osteoporosis treatment. However, the molecular mechanisms underlying the anti-osteoporotic effects of M. officinalis remain poorly understood.

Methods and results: In this study, we investigated the osteogenesis-promoting effects of MOS on human umbilical cord-derived mesenchymal stem cells (HUC-MSCs). Alkaline phosphatase staining, alizarin red staining, and quantitative reverse transcription-PCR demonstrated that MOS promoted the osteogenic differentiation of HUC-MSCs in a concentration-dependent manner. RNA sequencing results showed that the expression of key osteogenic differentiation-related genes, including BMP4, as well as the activity of transforming growth factor-β and calcium signaling pathways increased following MOS treatment. Furthermore, treatment with the bone morphogenetic protein (BMP) antagonist Noggin reversed the MOS-induced pro-osteogenic differentiation effects and the upregulation of osteoblast-specific markers.

Conclusions: Overall, the results indicate that MOS can partially promote osteogenic differentiation of HUC-MSCs by regulating the BMP-SMAD signaling pathway. These findings indicate the potential utility of MOS as a therapeutic agent for osteoporosis, particularly in the context of stem cell therapy.