1: Chem Phys Lipids. 2006 Oct;144(1):108-16. Epub 2006 Aug 15. 

Effect of the antibiotic azithromycin on thermotropic behavior of DOPC or DPPC

Fa N, Ronkart S, Schanck A, Deleu M, Gaigneaux A, Goormaghtigh E,
Mingeot-Leclercq MP.

Unite de Pharmacologie Cellulaire et Moleculaire, Universite Catholique de
Louvain, 73.70 Avenue E. Mounier 73, B-1200 Brussels, Belgium.

Azithromycin is a macrolide antibiotic known to bind to lipids and to affect
endocytosis probably by interacting with lipid membranes [Tyteca, D., Schanck,
A., Dufrene, Y.F., Deleu, M., Courtoy, P.J., Tulkens, P.M., Mingeot-Leclercq,
M.P., 2003. The macrolide antibiotic azithromycin interacts with lipids and
affects membrane organization and fluidity: studies on Langmuir-Blodgett
monolayers, liposomes and J774 macrophages. J. Membr. Biol. 192, 203-215]. In
this work, we investigate the effect of azithromycin on lipid model membranes
made of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or
1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Thermal transitions of both
lipids in contact with azithromycin are studied by (31)P NMR and DSC on
multilamellar vesicles. Concerning the DPPC, azithromycin induces a suppression
of the pretransition whereas a phase separation between the DOPC and the
antibiotic is observed. For both lipids, the enthalpy associated with the phase
transition is strongly decreased with azithromycin. Such effects may be due to
an increase of the available space between hydrophobic chains after insertion of
azithromycin in lipids. The findings provide a molecular insight of the phase
merging of DPPC gel in DOPC fluid matrix induced by azithromycin [Berquand, A.,
Mingeot-Leclercq, M.P., Dufrene, Y.F., 2004. Real-time imaging of drug-membrane
interactions by atomic force microscopy. Biochim. Biophys. Acta 1664, 198-205]
and could help to a better understanding of azithromycin-cell interaction.

PMID: 17007828 [PubMed - in process]