Fig. 1

Enhanced osteogenic differentiation of BMSCs by MEL treatment. a Relative mRNA levels of osteogenic marker genes in human BMSCs treated with MEL. The ALP, RUNX2, and OPN mRNA levels in BMSCs were measured by qRT-PCR. b ALP, RUNX2, and OPN protein levels in human BMSCs treated with MEL. Western blot analysis was used to detect protein levels using GAPDH as the internal standard. c Elevated ALP expression in human BMSCs caused by MEL treatment. ALP expression in BMSCs was measured by the ALP staining method. Left are gross scanning images (scale bar: 1 mm), the middle are enlarged images (magnification: × 250, scale bar: 160 μm), and the right is quantification of the left gross scanning images. d MEL promotes osteogenic differentiation of human BMSCs. The osteogenic differentiation of BMSCs was evaluated by Alizarin Red staining. Left are gross scanning images (scale bar: 1 mm), the middle are enlarged images (magnification: × 250, scale bar: 160 μm), and the right is quantification of the left gross scanning images. CON: control; MEL: melatonin; ALP: alkaline phosphatase; RUNX2: runt-related transcription factor 2; OPN: osteopontin; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; BMSCs: bone marrow mesenchymal stem cells; *P < 0.05, ***P < 0.001