title: Capsaicin Fluidifies the Membrane and Localizes Itself near the Lipid-Water Interface.
abstract: Capsaicin is the chemical responsible for making some peppers spicy hot, but additionally it is used as a pharmaceutical to alleviate different pain conditions. Capsaicin binds to the vanilloid receptor TRPV1, which plays a role in coordinating chemical and physical painful stimuli. A number of reports have also shown that capsaicin inserts in membranes and its capacity to modify them may be part of its molecular mode of action, affecting the activity of other membrane proteins. We have used differential scanning calorimetry, X-ray diffraction, (31)P NMR, and (2)H NMR spectroscopy to show that capsaicin increases the fluidity and disorder of 1,2-palmitoyl-sn-glycero-3-phosphocholine membrane models. By using (1)H NOESY MAS NMR based on proton-proton cross-peaks between capsaicin and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine resonances, we determined the location profile of this molecule in a fluid membrane concluding that it occupies the upper part of the phospholipid monolayer, between the lipid-water interface and the double bond of the acyl chain in position sn-2. This location explains the disorganization of the membrane of both the lipid-water interface and the hydrophobic palisade.
authors.affiliation: IMIB-Arrixaca, Campus of International Excellence "Mare Nostrum", Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia , Murcia E-30080, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Torrecillas
authors.affiliation: IMIB-Arrixaca, Campus of International Excellence "Mare Nostrum", Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia , Murcia E-30080, Spain.
authors.forename: Monika
authors.initials: M
authors.lastname: Schneider
authors.affiliation: IMIB-Arrixaca, Campus of International Excellence "Mare Nostrum", Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia , Murcia E-30080, Spain.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Fernández-Martínez
authors.affiliation: IMIB-Arrixaca, Campus of International Excellence "Mare Nostrum", Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia , Murcia E-30080, Spain.
authors.forename: Alessio
authors.initials: A
authors.lastname: Ausili
authors.affiliation: IMIB-Arrixaca, Campus of International Excellence "Mare Nostrum", Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia , Murcia E-30080, Spain.
authors.forename: Ana M
authors.initials: AM
authors.lastname: de Godos
authors.affiliation: IMIB-Arrixaca, Campus of International Excellence "Mare Nostrum", Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia , Murcia E-30080, Spain.
authors.forename: Senena
authors.initials: S
authors.lastname: Corbalán-García
authors.affiliation: IMIB-Arrixaca, Campus of International Excellence "Mare Nostrum", Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia , Murcia E-30080, Spain.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Gómez-Fernández
mesh_terms: D002152:Calorimetry, Differential Scanning; D002211:Capsaicin / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008051:Lipid Bilayers / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D010713:Phosphatidylcholines / Q000737:chemistry / Q000378:metabolism; D010759:Phosphorus Isotopes; D014316:Tritium; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D010759:Phosphorus Isotopes; D014867:Water; D014316:Tritium; D002211:Capsaicin; C028694:1-palmitoyl-2-oleoylphosphatidylcholine
keywords: 1H NOESY MAS NMR; 2H NMR; Capsaicin; DSC; SAXD; WAXD; membranes