Dimethyl Sulfoxide Shifts Human Mesenchymal Stem Cell Differentiation toward Adipogenesis over Osteogenesis

Dimethyl sulfoxide (DMSO) is extensively used as a solvent in bioactive compound screening due to its capacity to solubilize a wide range of chemical compounds. This study demonstrates that DMSO significantly influences lineage commitment in human bone marrow-derived mesenchymal stem cells (hBM-MSCs) by enhancing adipogenesis and inhibiting osteogenesis. At concentrations above 25 mM (0.32% in culture media), DMSO significantly promoted adipogenic differentiation in hBM-MSCs. Under osteogenic conditions, however, DMSO suppressed mineralization and downregulated the expression of osteoblast markers, thereby reducing osteoblast differentiation. Notably, DMSO also increased the adipocyte population within a predominantly osteogenic environment, suggesting it may shift the balance of hBM-MSC lineage commitment toward adipogenesis over osteogenesis. These findings emphasize the importance of careful consideration when utilizing DMSO as a solvent in studies involving hBMMSCs differentiation and the biological evaluation of test compounds.