TY  - JOUR
A1  - Koch, Alexander
A1  - Grammatikos, Georgios
A1  - Trautmann, Sandra
A1  - Schreiber, Yannick
A1  - Thomas, Dominique Jeanette
A1  - Bruns, Franziska
A1  - Pfeilschifter, Josef
A1  - Badenhoop, Klaus
A1  - Penna Martinez, Marissa
T1  - Vitamin D supplementation enhances C18(dihydro)ceramide levels in type 2 diabetes patients
T2  - International journal of molecular sciences
N2  - Sphingolipids are characterized by a broad range of bioactive properties. Particularly, the development of insulin resistance, a major pathophysiological hallmark of Type 2 Diabetes mellitus (T2D), has been linked to ceramide signaling. Since vitamin D supplementation may slow down T2D progression by improving glucose concentrations and insulin sensitivity, we investigated whether vitamin D supplementation impacts on plasma sphingolipid levels in T2D patients. Thus, plasma samples of 59 patients with non-insulin-requiring T2D from a placebo-controlled, randomized, and double-blind study were retrospectively analyzed. Once per week, patients received either 20 drops of Vigantol oil, corresponding to a daily dose of 1904 IU/d vitamin D (verum: n = 31), or a placebo oil consisting of medium chain triglycerides (placebo: n = 28). Blood samples were taken from all of the participants at three different time points: 1) at the beginning of the study (baseline), 2) after 6 months supplementation, and 3) after an additional 6 months of follow-up. Plasma sphingolipids were measured by high-performance liquid chromatography tandem mass spectrometry. At baseline and 6 months follow-up, no significant differences in plasma sphingolipid species were detected between the placebo and verum groups. After 6 months, vitamin D supplementation significantly enhanced plasma C18dihydroceramide (dhCer; N-stearoyl-sphinganine (d18:0/18:0)) and C18ceramide (Cer; N-stearoyl-sphingosine (d18:1/18:0)) levels were observed in the verum group compared to the placebo group. This was accompanied by significantly higher 25-hydroxyvitamin D3 (25(OH)D3) blood levels in patients receiving vitamin D compared to the placebo group. Taken together, vitamin D supplementation induced changes of the C18 chain-length-specific dhCer and Cer plasma levels in patients with T2D. The regulation of sphingolipid signaling by vitamin D may thus unravel a novel mechanism by which vitamin D can influence glucose utilization and insulin action. Whether this acts favorably or unfavorably for the progression of T2D needs to be clarified.
KW  - vitamin D
KW  - Type 2 Diabetes mellitus
KW  - sphingolipid metabolism
KW  - ceramide
KW  - dihydroceramide
KW  - sphingosine 1-phosphate
Y1  - 2017
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/45815
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-458159
SN  - 1422-0067
SN  - 1661-6596
N1  - This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
VL  - 18
IS  - 7, Art. 1532
SP  - 1
EP  - 10
PB  - Molecular Diversity Preservation International
CY  - Basel
ER  -