Natural Polyphenol Corilagin Enhances Osteogenesis and Chondrogenesis Differentiation of Mesenchymal Stem Cells: Implications for Bone and Cartilage Regeneration

Corilagin is a hydrolyzable ellagitannin and naturally occurring polyphenolic compound widely distributed in medicinal plants. It is also present in longan (<i>Dimocarpus longan</i>), known as <i>lumyai</i> in Thailand, a subtropical fruit extensively cultivated across China and Southeast Asia. Corilagin has been reported to exhibit strong antioxidant, anti-inflammatory, hepatoprotective, and anticancer activities through modulation of multiple cellular signaling pathways. However, despite these well-established pharmacological properties, its potential role in regulating bone marrow mesenchymal stem cell (BM-MSC) differentiation has not been fully explored in biomedical applications. In this study, we investigated the effects of corilagin on BM-MSC viability, protein-binding interactions, and lineage-specific differentiation toward osteogenic and chondrogenic pathways. Cytotoxicity assessment using human synovial SW-982 cells demonstrated that corilagin maintained cell viability at concentrations ranging from 1.56 to 50 µg/mL within 48 h, whereas prolonged exposure resulted in a time-dependent reduction in viability. In BM-MSCs, corilagin significantly enhanced osteogenic and chondrogenic differentiation in a dose-dependent manner, as evidenced by increased mineral deposition and cartilage matrix formation, as revealed by Alizarin Red S, Toluidine Blue, and Alcian Blue staining. Quantitative analyses further showed the upregulation of key lineage-specific genes, including Runx2 and osteopontin (OPN) for osteogenesis and Sox9 and aggrecan for chondrogenesis. Protein-binding assays confirmed the molecular interaction capacity of corilagin, supporting its biological activity. Overall, these findings demonstrate that corilagin promotes MSC-mediated osteogenic and chondrogenic differentiation while maintaining acceptable cytocompatibility, highlighting its potential as a natural small-molecule candidate for bone and cartilage tissue engineering and other biomedical fields with regenerative medicine applications.