title: Curcumin inhibits hERG potassium channels in vitro.
abstract: Curcumin is reported to exert antioxidant, anti-inflammatory, antiviral, antibacterial, antifungal, and anti-tumor activities. The human ether-a-go-go related gene (hERG) encodes the rapid component of the delayed rectifier K⁺ currents. Inhibition of hERG K⁺ channels leads to cardiac repolarization prolongation, which contributes to either the anti-arrhythmic effects of anti-arrhythmic drugs, or the pro-arrhythmic effects (induction of long QT syndrome) of some drugs not used for anti-arrhythmias. Since curcumin shows multiple beneficial effects and clinical significance, the aim of the present study is to investigate the effect of curcumin on hERG K⁺ channels, elucidating its potential cardiac therapeutic or toxic effects. In whole-cell patch-clamp experiments, we found that curcumin inhibited hERG K⁺ currents in HEK293 cells stably expressing hERG channels in a dose-dependent manner, with IC₅₀ value of 5.55 μM. The deactivation, inactivation and the recovery time from inactivation of hERG channels were significantly changed by acute treatment of 10 μM curcumin. Incubation of 20 μM curcumin for 24h reduced the HEK293 cell viability. Intravenous injection of maximal amount of curcumin in rabbits (20 mg/animal) did not affect the cardiac repolarization manifested with QTc value. We conclude that curcumin inhibits hERG K⁺ channels in vitro.
authors.affiliation: Department of Pharmacology, The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education, Harbin Medical University, Baojian Road 157, Harbin 150086, Heilongjiang Province, PR China.
authors.forename: Chao-Wei
authors.initials: CW
authors.lastname: Hu
authors.forename: Yue
authors.initials: Y
authors.lastname: Sheng
authors.forename: Qin
authors.initials: Q
authors.lastname: Zhang
authors.forename: Hui-Bin
authors.initials: HB
authors.lastname: Liu
authors.forename: Xin
authors.initials: X
authors.lastname: Xie
authors.forename: Wen-Chao
authors.initials: WC
authors.lastname: Ma
authors.forename: Rong
authors.initials: R
authors.lastname: Huo
authors.forename: De-Li
authors.initials: DL
authors.lastname: Dong
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D003474:Curcumin / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D000072237:ERG1 Potassium Channel; D004562:Electrocardiography; D051638:Ether-A-Go-Go Potassium Channels / Q000037:antagonists & inhibitors*; D005260:Female; D057809:HEK293 Cells / Q000187:drug effects / Q000378:metabolism; D006321:Heart / Q000187:drug effects; D006801:Humans; D008297:Male; D018408:Patch-Clamp Techniques; D011817:Rabbits
chemical_list: D000072237:ERG1 Potassium Channel; D051638:Ether-A-Go-Go Potassium Channels; C000606913:KCNH2 protein, human; D003474:Curcumin