title: Lutein inhibits the function of the transient receptor potential A1 ion channel in different in vitro and in vivo models.
abstract: Transient receptor potential (TRP) ion channels, such as TRP vanilloid 1 and ankyrin repeat domain 1 (TRPV1 and TRPA1), are expressed on primary sensory neurons. Lutein, a natural tetraterpene carotenoid, can be incorporated into membranes and might modulate TRP channels. Therefore, the effects of the water-soluble randomly methylated-β-cyclodextrin (RAMEB) complex of lutein were investigated on TRPV1 and TRPA1 activation. RAMEB-lutein (100 μM) significantly diminished Ca(2+) influx to cultured rat trigeminal neurons induced by TRPA1 activation with mustard oil, but not by TRPV1 stimulation with capsaicin, as determined with microfluorimetry. Calcitonin gene-related peptide release from afferents of isolated tracheae evoked by mustard oil, but not by capsaicin, was inhibited by RAMEB-lutein. Mustard oil-induced neurogenic mouse ear swelling was also significantly decreased by 100 μg/ml s.c. RAMEB-lutein pretreatment, while capsaicin-evoked edema was not altered. Myeloperoxidase activity indicating non-neurogenic granulocyte accumulation in the ear was not influenced by RAMEB-lutein in either case. It is concluded that lutein inhibits TRPA1, but not TRPV1 stimulation-induced responses on cell bodies and peripheral terminals of sensory neurons in vitro and in vivo. Based on these distinct actions and the carotenoid structure, the ability of lutein to modulate lipid rafts in the membrane around TRP channels can be suggested.
authors.affiliation: Department of Pharmacognosy, Medical School, University of Pécs, Rókus utca 2, Pécs, 7624, Hungary.
authors.forename: Györgyi
authors.initials: G
authors.lastname: Horváth
authors.forename: Éva
authors.initials: É
authors.lastname: Szoke
authors.forename: Ágnes
authors.initials: Á
authors.lastname: Kemény
authors.forename: Teréz
authors.initials: T
authors.lastname: Bagoly
authors.forename: József
authors.initials: J
authors.lastname: Deli
authors.forename: Lajos
authors.initials: L
authors.lastname: Szente
authors.forename: Szilárd
authors.initials: S
authors.lastname: Pál
authors.forename: Katalin
authors.initials: K
authors.lastname: Sándor
authors.forename: János
authors.initials: J
authors.lastname: Szolcsányi
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Helyes
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005260:Female; D014975:Lutein / Q000494:pharmacology* / Q000502:physiology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D020078:Neurogenic Inflammation / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011984:Sensory Receptor Cells / Q000187:drug effects / Q000378:metabolism; D000074025:TRPA1 Cation Channel; D050052:TRPC Cation Channels / Q000037:antagonists & inhibitors* / Q000378:metabolism; D050916:TRPV Cation Channels / Q000037:antagonists & inhibitors / Q000378:metabolism; D050051:Transient Receptor Potential Channels / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D000074025:TRPA1 Cation Channel; D050052:TRPC Cation Channels; D050916:TRPV Cation Channels; C493921:TRPV1 protein, mouse; D050051:Transient Receptor Potential Channels; C475685:Trpa1 protein, mouse; C480976:Trpa1 protein, rat; C493922:Trpv1 protein, rat; D014975:Lutein