Permanent address: Departamento de Física, Universidade Federal de Viçosa, Viçosa, Brazil.
Influence of melatonin on the order of phosphatidylcholine-based membranes
Version of Record online: 25 JUN 2010
© 2010 The Authors. Journal compilation © 2010 John Wiley & Sons A/S
Journal of Pineal Research
Volume 49, Issue 2, pages 169–175, September 2010
How to Cite
De Lima, V. R., Caro, M. S. B., Munford, M. L., Desbat, B., Dufourc, E., Pasa, A. A. and Creczynski-Pasa, T. B. (2010), Influence of melatonin on the order of phosphatidylcholine-based membranes. Journal of Pineal Research, 49: 169–175. doi: 10.1111/j.1600-079X.2010.00782.x
- Issue online: 2 AUG 2010
- Version of Record online: 25 JUN 2010
- Received December 2; 2009 Accepted April 16; 2010.
- atomic force microscopy;
- membrane assembling;
- mica-supported bilayers;
Abstract: The effect of melatonin was evaluated on three phosphatidylcholine-based membrane models. Changes in liposome dynamics were monitored by fluorescence, following the response of the probe merocyanine-540, as well as by differential scanning calorimetry (DSC). Langmuir monolayers were investigated using molecular area measurements, as well as by Brewster angle microscopy (BAM). Mica-supported bilayers were observed via atomic force microscopy (AFM). Fluorescence results demonstrating that melatonin increases the affinity between MC-540 and lipid molecules possibly because of an increase in the membrane fluidity in liposomes. DSC analyses showed that melatonin promoted a reduction in enthalpy in the lipid nonpolar chains. Melatonin also promoted an increase in the molecular area of Langmuir monolayers, as well as a decrease in membrane thickness. Consequently, melatonin appeared to induce re-ordering effects in liposome and Langmuir monolayers. AFM images of bilayers immobilized on mica suggested that melatonin induced a gel state predominance or a delay in the main phase transition. At experimental conditions, melatonin interacted actively with all membranes models tested and induced changes in their physico-chemical properties. The data presented here may contribute to the understanding of melatonin physiologic properties, as well as the development of therapeutic advanced systems, such as drug delivery systems and biosensors.