title: Suppression of Helicobacter pylori-induced gastritis by green tea extract in Mongolian gerbils.
abstract: Since urease of Helicobacter pylori is essential for its colonization, we focused attention on foodstuffs which inhibit the activity of this enzyme. Among plant-derived 77 foodstuff samples tested, some tea and rosemary extracts were found to clearly inhibit H. pylori urease in vitro. In particular, green tea extract (GTE) showed the strongest inhibition of H. pylori urease, with an IC(50) value of 13 microg/ml. Active principles were identified to be catechins, the hydroxyl group of 5(')-position appearing important for urease inhibition. Furthermore, when H. pylori-inoculated Mongolian gerbils were given GTE in drinking water at the concentrations of 500, 1000, and 2000 ppm for 6 weeks, gastritis and the prevalence of H. pylori-infected animals were suppressed in a dose-dependent manner. Since the acquisition by H. pylori of resistance to antibiotics has become a serious problem, tea and tea catechins may be very safe resources to control H. pylori-associated gastroduodenal diseases.
authors.affiliation: Cancer Prevention Basic Research Project, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Matsubara
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Shibata
authors.forename: Fumiyasu
authors.initials: F
authors.lastname: Ishikawa
authors.forename: Teruo
authors.initials: T
authors.lastname: Yokokura
authors.forename: Mami
authors.initials: M
authors.lastname: Takahashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugimura
authors.forename: Keiji
authors.initials: K
authors.lastname: Wakabayashi
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005756:Gastritis / Q000382:microbiology*; D005849:Gerbillinae; D016480:Helicobacter pylori / Q000378:metabolism*; D020128:Inhibitory Concentration 50; D008297:Male; D010936:Plant Extracts; D013662:Tea; D014510:Urease / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D010936:Plant Extracts; D013662:Tea; D014510:Urease