Interaction between vitamin D-2 and magnesium in liposomes: Differential scanning calorimetry and FTIR spectroscopy studies

Toyran, Neslihan
Severcan, Feride
Magnesium (Mg (2+)) ion is of great importance in physiology by its intervention in 300 enzymatic systems, its role in membrane structure, its function in neuromuscular excitability and vitamin D metabolism and/or action. In the present study, the interaction of Mg2+, at low (1 mole %) and high (7 mole %) concentrations with dipalmitoyl phosphatidylcholine (DPPC) liposomes has been studied in the presence and absence of vitamin D-2 (I mole %) by using two noninvasive techniques, namely differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. DSC studies reveal that the presence of vitamin D-2 in the pure or Mg2+ (at both low and high concentrations) containing liposomes diminishes the pretransition. The calorimetric results also reveal that, inclusion of Mg (2+) (more significantly at high concentration) into pure or vitamin D-2 containing DPPC liposomes increases the main phase transition temperature. The investigation of the CH2 Symmetric, the CH3 asymmetric, the C=O stretching, and the PO2- antisymmetric double bond stretching bands in FTIR spectra with respect to changes occurring in the wavenumber and/or the bandwidth values as a function of temperature reveal that, inclusion of vitamin D2 or Mg2+ into pure DPPC liposomes orders and decreases the dynamics of the acyl chains in both gel and liquid-crystalline phases and does not induce hydrogen bond formation in the interfacial region. Furthermore, the dynamics of the head groups of the liposomes decreases in both phases. Our findings reveal that, simultaneous presence of vitamin D-2 and Mg (2+) alters the effect of each other, which is reflected as a decrease in the interactions between these two additives within the model membrane.


The effect of magnesium ions on vitamin D-2-phospholipid model membrane interactions in the presence of different buffer media
Toyran, N; Severcan, Feride (2000-10-02)
Vitamin D plays important roles in the bone formation, in calcium and phosphorus homeostasis and in the treatment and prevention of many diseases. Ions, especially divalent cations like Mg2+, have indispensable roles in many vital biological events. Mg2+ is involved in many fundamental processes such as stabilization of membranes and macromolecules, synthesis of nucleic acid and proteins and formation and use of high-energy phosphate bonds. Mg2+ is also required for synthesis of more than 310 different enzy...
KARAKURT, SERDAR; Adalı, Orhan (2011-01-01)
Glutathione S-transferase and NAD(P)H: quinone oxidoreductase 1 enzymes have important roles in detoxification and also activation of a wide variety of chemicals. Moreover, resistance of tumor cells against chemotherapeutic agents has been implicated in GST activities. The aim of this study was to investigate the effect of polyphenolic compound tannic acid on rabbit liver and kidney glutathione S-transferase and NAD(P)H: quinone oxidoreductase 1 enzyme activities. Tannic acid was found to be a potent inhibi...
Effect of protein aggregation in the aqueous phase on the binding of membrane proteins to membranes
Doebler, R; Basaran, N; Goldston, H; Holloway, PW (Elsevier BV, 1999-02-01)
Analysis of the binding of hydrophobic peptides or proteins to membranes generally assumes that the solute is monomeric in both the aqueous phase and the membrane. Simulations were performed to examine the effect of solute self-association in the aqueous phase on the binding of monomeric solute to lipid vesicles. Aggregation lowered the initial concentration of monomeric solute, which was then maintained at a relatively constant value at the expense of the aggregated solute, as the lipid concentration was i...
Analysis of ligand-receptor cross-linked fragments by mass spectrometry
Son, Çağdaş Devrim; Hurst, GB; Naider, F; Becker, JM (Wiley, 2005-03-01)
G-protein coupled receptors (GPCRs) are a class of integral membrane receptor proteins that are characterized by a signature seven-transmembrane (7-TM) configuration. The alpha-factor receptor (Ste2p) from Saccharomyces cerevisiae is a GPCR that, upon binding of a peptide ligand, transduces a signal to initiate a cascade of events leading to the mating of haploid yeast cells. This study summarizes the application of affinity purification and of matrix-assisted laser-desorption ionization time-of-flight (MAL...
Effects of the non-steroidal anti-inflammatory drug celecoxib on cholesterol containing distearoyl phosphatidylcholine membranes
Sade, Asli; Banerjee, Sreeparna; Severcan, Feride (2011-01-01)
The effects of different concentrations of celecoxib on the acyl chain order, dynamics and the hydration status of the head group and interfacial region of model membranes containing DSPC and cholesterol were investigated in detail using Fourier transform infrared spectroscopy. Our results reveal that regardless of the presence of cholesterol, celecoxib is able to alter the physical properties of membranes. It exerts opposing effects on membrane order at high and low concentrations and decreases membrane fl...
Citation Formats
N. Toyran and F. Severcan, “Interaction between vitamin D-2 and magnesium in liposomes: Differential scanning calorimetry and FTIR spectroscopy studies,” JOURNAL OF MOLECULAR STRUCTURE, pp. 19–27, 2007, Accessed: 00, 2020. [Online]. Available: