Vitamin D effects on sphingosine 1-phosphate signaling and metabolism in monocytes from type 2 diabetes patients and controls

Publication date: Available online 15 October 2018Source: The Journal of Steroid Biochemistry and Molecular BiologyAuthor(s): Nojan Nejatian, Sandra Trautmann, Dominique Thomas, Josef Pfeilschifter, Klaus Badenhoop, Alexander Koch, Marissa Penna-MartinezABSTRACTElevated sphingosine 1-phopshate (S1P) concentration was observed in type 2 diabetes mellitus (T2D). On the other side, 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) can influence the formation of sphingosine 1-phopshate (S1P) and the expression of S1P receptors, which are known to be involved in T2D. In order to evaluate mechanisms for the antiinflammatory potential of 1,25(OH)2D3, we investigated whether 1,25(OH)2D3 alters S1P signaling and metabolism in human CD14+ monocytes. Primary monocytes isolated from healthy controls (HC) and T2D patients were treated for 24 h with 10 nM 1,25(OH)2D3 in the absence or presence of 500 IU/ml interleukin-(IL)-1β. Thereafter, sphingosine kinase (SPHK)1, SPHK2 and S1P receptor 1-5 (S1P1-5) mRNA expression levels were measured by TaqMan™ analyses. Sphingolipid levels in cell supernatant were determined by high-performance liquid chromatography/tandem mass spectrometry (LC-MS/MS). 1,25(OH)2D3 treatment downregulated S1P1 and S1P2 mRNA expression compared to untreated monocytes of HC and T2D patients. In contrast, SPHK1, S1P3 and S1P4 mRNA expression levels were upregulated by 1,25(OH)2D3 treatment compared to the respective controls. Furthermore, reduced S1P2 and increased S1P3 and...
Source: The Journal of Steroid Biochemistry and Molecular Biology - Category: Biochemistry Source Type: research