title: Activation of TRPV1 and TRPA1 by black pepper components.
abstract: We searched in this study for novel agonists of transient receptor potential cation channel, subfamily V, member 1 (TRPV1) and transient receptor potential cation channel, subfamily A, member 1 (TRPA1) in pepper, focusing attention on 19 compounds contained in black pepper. Almost all the compounds in HEK cells heterogeneously expressed TRPV1 or TRPA1, increased the intracellular Ca(2+) concentration ([Ca(2+)](i)) in a concentration-dependent manner. Among these, piperine, isopiperine, isochavicine, piperanine, pipernonaline, dehydropipernonaline, retrofractamide C, piperolein A, and piperolein B relatively strongly activated TRPV1. The EC(50) values of these compounds for TRPV1 were 0.6-128 microM. Piperine, isopiperine, isochavicine, piperanine, piperolein A, piperolein B, and N-isobutyl-(2E,4E)-tetradeca-2,4-diamide also relatively strongly activated TRPA1, the EC(50) values of these compounds for TRPA1 were 7.8-148 microM. The Ca(2+) responses of these compounds for TRPV1 and TRPA1 were significantly suppressed by co-applying each antagonist. We identified in this study new transient receptor potential (TRP) agonists present in black pepper and found that piperine, isopiperine, isochavicine, piperanine, piperolein A, and piperolein B activated both TRPV1 and TRPA1.
authors.affiliation: Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizouka, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Okumura
authors.forename: Masataka
authors.initials: M
authors.lastname: Narukawa
authors.forename: Yusaku
authors.initials: Y
authors.lastname: Iwasaki
authors.forename: Aiko
authors.initials: A
authors.lastname: Ishikawa
authors.forename: Hisashi
authors.initials: H
authors.lastname: Matsuda
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yoshikawa
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D015220:Calcium Channels / Q000378:metabolism; D002211:Capsaicin / Q000494:pharmacology; D006801:Humans; D017879:Isothiocyanates / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000819:agonists* / Q000378:metabolism; D029222:Piper nigrum / Q000737:chemistry*; D010936:Plant Extracts / Q000494:pharmacology*; D000074025:TRPA1 Cation Channel; D050916:TRPV Cation Channels / Q000819:agonists* / Q000378:metabolism; D050051:Transient Receptor Potential Channels / Q000819:agonists* / Q000378:metabolism
chemical_list: D015220:Calcium Channels; D017879:Isothiocyanates; D009419:Nerve Tissue Proteins; D010936:Plant Extracts; D000074025:TRPA1 Cation Channel; C473350:TRPA1 protein, human; D050916:TRPV Cation Channels; C494482:TRPV1 protein, human; D050051:Transient Receptor Potential Channels; C041942:2,3,4-tri-O-acetylarabinopyranosyl isothiocyanate; D002211:Capsaicin