title: The natural antioxidant rosmarinic acid spontaneously penetrates membranes to inhibit lipid peroxidation in situ.
abstract: Exogenous molecules from dietary sources such as polyphenols are very efficient in preventing the alteration of lipid membranes by oxidative stress. Among the polyphenols, we have chosen to study rosmarinic acid (RA). We investigated the efficiency of RA in preventing lipid peroxidation and in interacting with lipids. We used liposomes of 1,2-dilinoleoyl-sn-glycero-3-phosphocholine (DLPC) to show that RA was an efficient antioxidant. By HPLC, we determined that the maximum amount of RA associated with the lipids was ~1 mol%. Moreover, by using Langmuir monolayers, we evidenced that cholesterol decreases the penetration of RA. The investigation of transferred lipid/RA monolayers by atomic force microscopy revealed that 1 mol% of RA in the membrane was not sufficient to alter the membrane structure at the nanoscale. By fluorescence, we observed no significant modification of membrane permeability and fluidity caused by the interaction with RA. We also deduced that RA molecules were mainly located among the polar headgroups of the lipids. Finally, we prepared DLPC/RA vesicles to evidence for the first time that up to 1 mol% of RA inserts spontaneously in the membrane, which is high enough to fully prevent lipid peroxidation without any noticeable alteration of the membrane structure due to RA insertion.
authors.affiliation: Université de Technologie de Compiègne-CNRS, UMR 6022 Génie Enzymatique et Cellulaire, BP 20529, 60205 Compiègne Cedex, France.
authors.forename: Ophélie
authors.initials: O
authors.lastname: Fadel
authors.forename: Karim
authors.initials: K
authors.lastname: El Kirat
authors.forename: Sandrine
authors.initials: S
authors.lastname: Morandat
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects*; D002463:Cell Membrane Permeability; D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000494:pharmacology*; D053630:Depsides / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects*; D018625:Microscopy, Atomic Force; D000097123:Rosmarinic Acid
chemical_list: D000975:Antioxidants; D002934:Cinnamates; D053630:Depsides; D000097123:Rosmarinic Acid