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Updated: Oct 15, 2026
Isolation of Mesenchymal Stem Cells from Human Alveolar Periosteum and Effects of Vitamin D on Osteogenic Activity of Periosteum-derived Cells
Published on: May 4, 2018
1,25 dihydroxyvitamin D(3) activates sphingomyelin turnover in ROS17/2.8 osteosarcoma cells without
R Liu1, Y Xu, M C Farach-Carson
1Department of Biological Sciences, University of Delaware, Newark, Delaware, USA.
Abstract:
1,25-Dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] initiates the hydrolysis of sphingomyelin in ROS 17/2.8 osteosarcoma cells with the resultant generation of cell-associated ceramide. Increases in ceramide levels were detectable at 15 min and maximal one hour after exposure of cells to 1,25(OH)(2)D(3). Neither 1,25(OH)(2)D(3) nor exogenous ceramide elicited a change in cytosolic free Ca(2+) ([Ca(2+)](i)). Transient elevations in [Ca(2+)](i) were observed when cells were exposed to exogenous sphingosine, but there was no detectable conversion of ceramide to sphingosine in 1, 25(OH)(2)D(3)-treated cells. Ceramide also did not stimulate Ca(2+) uptake across ROS 17/2.8 cell plasma membranes. Collectively, these results suggest that 1,25(OH)(2)D(3) activates sphingomyelin turnover in ROS 17/2.8 osteosarcoma cells but that the sphingolipid metabolite ceramide is not responsible for 1,25(OH)(2)D(3)-induced activation of plasma membrane Ca(2+) channels.
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