Interaction between Amphotericin B and Sterols in Monolayers. Mixed Films of Ergosterol−Amphotericin B

Abstract

Analysis of the compression isotherms of ergosterol/amphotericin B (AmB) mixed monolayers spread on aqueous substrates shows the existence of interactions between the two components at AmB mole fractions between 0.1 and 0.7. At low surface pressure AmB molecules appear to lie horizontally in the A/W interface and ergosterol molecules to stand vertically, while at higher surface pressures the molecules of both components are vertically oriented at the interface.

Interactions between membrane sterols and phospholipids in model mammalian and fungi cellular membranes — A Langmuir monolayer study

“…This indicates that mixed cholesterol/phospholipid monolayers are more rigid as compared to pure DPPC films. This condensing effect of cholesterol on lipid monolayes is well known and has been frequently described in literature [15,21,39].…”

“…This explains the fact that the affinity of the antibiotic or its derivatives towards ergosterol was found to be higher as compared to cholesterol [18,21,43,44]. …”

“…To understand their role in the polyenes mechanism of action, it is of utmost importance to study the interactions between the antibiotic and phospholipids in the presence of sterols. Until now, the Langmuir monolayer technique was applied to examine the interactions between polyene antibiotics and either sterol [20,21] or phospholipids [22,23]. However, to understand the complex mechanism of action of the polyene antifungal it is necessary to study the interactions between the antibiotic and the lipidic components of the fungi and mammalian cellular membranes (phospholipids and sterols).…”

Interactions of amphotericin B derivative of low toxicity with biological membrane components—the Langmuir monolayer approach

“…In particular, mixed monolayers composed of constituents of biological membranes, such as phospholipids, sterols and glycolipids, provide a highly informative approach for studying intermolecular interactions between membrane components, usually phospholipids, and biomolecules, for example, various drugs [2][3][4][5], hormones [6,7], enzymes [8][9][10][11], proteins [12][13][14][15][16][17][18][19][20][21], etc. Such investigations may be of much help in elucidating a mode of action of many physiological active compounds [22][23][24][25][26][27][28][29]. An excellent review article by Maget-Dana [30] provides a brief description of the monolayer technique and summarizes its biomedical applications.…”

“…Another approach, useful for water insoluble biomolecules, is based on co-spreading of phospholipid/sterol molecules and the biomolecules on the water surface as a mixed Langmuir monolayer [5,[24][25][26][27][28][29]. Upon varying the proportion of both types of molecules in the monolayer and analyzing the stability and miscibility of the investigated mixed system with the simple functions or thermodynamic parameters, one may infer on the nature and strength of interaction between film molecules [33].…”