Differential scanning calorimetric study of the effect of vitamin D3 on the thermotropic phase behavior of lipids model systems.
Differential scanning calorimetry has been used to investigate the effects of vitamin D3 on the physical properties of model membranes including pure phosphatidylcholines (PC's) of chain length from 14 to 18, pure dipalmitoylphosphatidylethanolamine (DPPE), and various mixtures of these lipids. The results demonstrate that the interactions of vitamin D3 with PC's are dependent on acyl chain lengths. It was found that vitamin D3 reduces the transition temperatures of PC's and PE's, broadening the transition and reducing the enthalpy, eventually abolishing the transition. The interaction of vitamin D3 with PC varies with chain length; the transition of DMPC is abolished by only 15 mol% vitamin D3 whereas 45 mol% vitamin D3 is required to abolish the transition of DSPC. These variations in vitamin D3 lipid interactions are further explored in various mixtures. In the mixture studies it is shown that vitamin D3 affects the mixing properties of the lipids in the mixtures. The results suggest that the presence of vitamin D3 in lipids can affect the lateral phase distributions of lipids, and thereby have important effects on membrane function.
Bondar
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OP
Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City 66103, USA.
Rowe
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ES
D002152:Calorimetry, Differential Scanning; D002762:Cholecalciferol / Q000737:chemistry* / Q000494:pharmacology; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D008563:Membrane Lipids / Q000737:chemistry*; D008567:Membranes, Artificial; D010713:Phosphatidylcholines / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics
D008563:Membrane Lipids; D008567:Membranes, Artificial; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D002762:Cholecalciferol; C007510:1,2-dipalmitoyl-3-phosphatidylethanolamine; D004134:Dimyristoylphosphatidylcholine