Localization and interactions of melatonin in dry cholesterol/lecithin mixed reversed micelles used as cell membrane models
Article first published online: 26 JAN 2005
Journal of Pineal Research
Volume 38, Issue 4, pages 292–298, May 2005
How to Cite
Bongiorno, D., Ceraulo, L., Ferrugia, M., Filizzola, F., Ruggirello, A. and Liveri, V. T. (2005), Localization and interactions of melatonin in dry cholesterol/lecithin mixed reversed micelles used as cell membrane models. Journal of Pineal Research, 38: 292–298. doi: 10.1111/j.1600-079X.2005.00211.x
- Issue published online: 26 JAN 2005
- Article first published online: 26 JAN 2005
- Received October 4, 2004; accepted November 29, 2004.
- cell membrane models;
- confinement effects;
- reversed micelles
Abstract: The state of melatonin confined in dry cholesterol/lecithin mixed reversed micelles dispersed in CCl4 was investigated using 1H-NMR and FT-IR spectroscopies as a function of the melatonin to lecithin molar ratio (RMLT) and of the cholesterol to lecithin molar ratio (RCHL). An analysis of experimental results leads to the hypothesis that, independent of RMLT and as a consequence of anisotropic melatonin/lecithin, melatonin/cholesterol and cholesterol/lecithin interactions, melatonin is totally solubilized in reversed micelles. Melatonin is mainly located in and oriented in the nanodomain constituted by the hydrophilic groups of cholesterol and lecithin. A competition of melatonin and cholesterol for the hydrophilic binding sites of the reversed micelles was observed by changing the RCHL. Some possible biological implications of the specific interactions governing the solubilization process, the preferential location and the peculiar properties of melatonin confined in cholesterol/lecithin mixed reversed micelles are discussed.