title: Walnut polyphenols prevent liver damage induced by carbon tetrachloride and d-galactosamine: hepatoprotective hydrolyzable tannins in the kernel pellicles of walnut.
abstract: The polyphenol-rich fraction (WP, 45% polyphenol) prepared from the kernel pellicles of walnuts was assessed for its hepatoprotective effect in mice. A single oral administration of WP (200 mg/kg) significantly suppressed serum glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) elevation in liver injury induced by carbon tetrachloride (CCl 4), while it did not suppress d-galactosamine (GalN)-induced liver injury. In order to identify the active principles in WP, we examined individual constituents for the protective effect on cell damage induced by CCl 4 and d-GalN in primary cultured rat hepatocytes. WP was effective against both CCl 4- and d-GalN-induced hepatocyte damages. Among the constituents, only ellagitannins with a galloylated glucopyranose core, such as tellimagrandins I, II, and rugosin C, suppressed CCl 4-induced hepatocyte damage significantly. Most of the ellagitannins including tellimagrandin I and 2,3- O-hexahydroxydiphenoylglucose exhibited remarkable inhibitory effect against d-GalN-induced damage. Telliamgrandin I especially completely suppressed both CCl 4- and d-GalN-induced cell damage, and thus is likely the principal constituent for the hepatoprotective effect of WP.
authors.affiliation: Research & Development Division, Oryza Oil & Fat Chemical Co., Ltd., 1 Numata, Kitagata-cho, Ichinomiya, Aichi 493-8001, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shimoda
authors.forename: Junji
authors.initials: J
authors.lastname: Tanaka
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Toshiyuji
authors.initials: T
authors.lastname: Fukuda
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ito
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Hatano
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshida
mesh_terms: D000818:Animals; D002251:Carbon Tetrachloride; D002478:Cells, Cultured; D056486:Chemical and Drug Induced Liver Injury; D005419:Flavonoids / Q000008:administration & dosage* / Q000302:isolation & purification; D005688:Galactosamine; D005707:Gallic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives; D005960:Glucosides / Q000008:administration & dosage; D006868:Hydrolysis; D031324:Juglans / Q000737:chemistry*; D008107:Liver Diseases / Q000517:prevention & control*; D010636:Phenols / Q000008:administration & dosage* / Q000302:isolation & purification; D059808:Polyphenols; D051381:Rats; D012639:Seeds / Q000737:chemistry*; D013634:Tannins / Q000008:administration & dosage* / Q000378:metabolism
chemical_list: D005419:Flavonoids; D005960:Glucosides; D010636:Phenols; D059808:Polyphenols; D013634:Tannins; D005707:Gallic Acid; D005688:Galactosamine; C087926:tellimagrandin I; D002251:Carbon Tetrachloride