title: Curcumin produces an antihyperalgesic effect via antagonism of TRPV1.
abstract: Curcumin has diverse therapeutic effects, such as anti-inflammatory, anti-oxidant, anti-cancer, and antimicrobial activities. The vanilloid moiety of curcumin is considered important for activation of the transient receptor potential vanilloid 1 (TRPV1), which plays an important role in nociception. However, very little is known about the effects of curcumin on nociception. In the present study, we investigated whether the anti-nociceptive effects of curcumin are mediated via TRPV1 by using nociceptive behavioral studies and in vitro whole-cell patch-clamp recordings in the trigeminal system. Subcutaneous injection of capsaicin in the vibrissa pad area of rats induced thermal hyperalgesia. Intraperitoneally administered curcumin blocked capsaicin-induced thermal hyperalgesia in a dose-dependent manner. Whereas curcumin reduced capsaicin-induced currents in a dose-dependent manner in both trigeminal ganglion neurons and TRPV1-expressing HEK 293 cells, curcumin did not affect heat-induced TRPV1 currents. Taken together, our results indicate that curcumin blocks capsaicin-induced TRPV1 activation and thereby inhibits TRPV1-mediated pain hypersensitivity.
authors.affiliation: Dental Research Institute and Department of Physiology, Seoul National University, Yeongeon-Dong Chongno-Ku, Korea.
authors.forename: K Y
authors.initials: KY
authors.lastname: Yeon
authors.forename: S A
authors.initials: SA
authors.lastname: Kim
authors.forename: Y H
authors.initials: YH
authors.lastname: Kim
authors.forename: M K
authors.initials: MK
authors.lastname: Lee
authors.forename: D K
authors.initials: DK
authors.lastname: Ahn
authors.forename: H J
authors.initials: HJ
authors.lastname: Kim
authors.forename: J S
authors.initials: JS
authors.lastname: Kim
authors.forename: S J
authors.initials: SJ
authors.lastname: Jung
authors.forename: S B
authors.initials: SB
authors.lastname: Oh
mesh_terms: D000818:Animals; D002211:Capsaicin / Q000008:administration & dosage / Q000494:pharmacology; D002460:Cell Line; D003474:Curcumin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D005157:Facial Pain / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D006358:Hot Temperature; D006801:Humans; D006930:Hyperalgesia / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D007274:Injections, Intraperitoneal; D007279:Injections, Subcutaneous; D007668:Kidney / Q000166:cytology / Q000196:embryology; D008297:Male; D009619:Nociceptors / Q000187:drug effects*; D009666:Nose; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D050916:TRPV Cation Channels / Q000037:antagonists & inhibitors / Q000502:physiology*; D012668:Trigeminal Ganglion / Q000166:cytology / Q000187:drug effects
chemical_list: D050916:TRPV Cation Channels; C493922:Trpv1 protein, rat; D003474:Curcumin; D002211:Capsaicin