Biopolymers and Cell. 2012; 28(2): 114-120

 

EFFECT OF THE VITAMIN D PHOTOSYNTHESIS PRODUCTS ON THERMODYNAMIC PARAMETERS OF MODEL LIPID MEMBRANES

 

Kasian N. A., Vashchenko O. V., 1Gluhova Ya. E., Lisetski L. N.


Institute for scintillation materials, STC «Institute for Single Crystals», NAS of Ukraine
60, Lenin ave., Kharkiv, Ukraine, 61001

1V. N. Karazin Kharkiv National University
4, Svobody Sq., Kharkiv, Ukraine, 61077

Aim. To compare effects of vitamin D (VitD), provitamin D (ProD) and its photo- and thermoisomerization products on thermodynamical parameters of hydrated dipalmitoylphoshpatidylcholine (DPPC) multilayers. Methods. Differential scanning calorimetry, UV spectroscopy. Results. A regular decrease was established in the melting temperature accompanied with the pronounced broadening of the appropriate peaks for DPPC multilayers doped with the sterols in the order ProD3 < < ProD3 + UV < ProD3 + UV + dark storage < VitD3. Conclusions. The destabilizing effect of VitD3 on the membrane appeared to be stronger than that of ProD3 and its photoisomerization products. This can facilitate VitD3 withdrawal from the membrane into intercellular space under its biosinthesis in vivo. A possible molecular mechanism of the phenomena observed is related to the higher conformational flexibility and anisometry of VitD3 as compared to ProD3.

 


Keywords: phospholipid membranes, vitamin D, provitamin D, photoisomerization, differential scanning calorimetry

 

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