title: Green and black tea inhibit cytokine-induced IL-8 production and secretion in AGS gastric cancer cells via inhibition of NF-κB activity.
abstract: Consumption of tea is associated with a reduced risk for several gastrointestinal cancers. Inflammatory processes, such as secretion of IL-8 from the gastric epithelium in response to chronic chemokine or antigen exposure, serve both as a chemoattractant for white blood cells and a prerequisite for gastric carcinogenesis. In this study, the gastric adenocarcinoma cell line AGS was used to investigate the effect of green tea extract, black tea extract, and epigallocatechin gallate (EGCG), the most abundant catechin in tea, on cytokine-induced inflammation. AGS cells were stimulated with interleukin-1β (IL-1β) to initiate inflammation, followed by exposure to either tea extracts or EGCG. We found that both green and black tea extracts at concentrations of 20 and 2 µM total catechins, respectively, significantly (p < 0.05) inhibited IL-1β-induced IL-8 production and secretion to a similar extent. Treatment of AGS cells with EGCG (8 µM) produced similar reductions in IL-1β-induced IL-8 production and secretion. Inhibition of NF-κB activity was found to be responsible, in part, for these observed effects. Our findings demonstrate that both green and black tea extracts with distinctly different catechin profiles, are capable of disrupting the molecular link between inflammation and carcinogenesis via inhibition of NF-κB activity in AGS cells.
authors.affiliation: Department of Human Nutrition, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Fabiola
authors.initials: F
authors.lastname: Gutierrez-Orozco
authors.forename: Brian R
authors.initials: BR
authors.lastname: Stephens
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Neilson
authors.forename: Rodney
authors.initials: R
authors.lastname: Green
authors.forename: Mario G
authors.initials: MG
authors.lastname: Ferruzzi
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Bomser
mesh_terms: D028241:Camellia sinensis / Q000737:chemistry*; D002392:Catechin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D002853:Chromatography, Liquid; D006801:Humans; D053583:Interleukin-1beta / Q000494:pharmacology; D016209:Interleukin-8 / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000187:drug effects; D013058:Mass Spectrometry; D016328:NF-kappa B / Q000378:metabolism*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D013274:Stomach Neoplasms / Q000378:metabolism*; D013662:Tea / Q000737:chemistry*
chemical_list: D053583:Interleukin-1beta; D016209:Interleukin-8; D016328:NF-kappa B; D010936:Plant Extracts; D013662:Tea; D002392:Catechin; C045651:epigallocatechin gallate