title: Effect of three flavonoids isolated from Japanese Polygonum species on superoxide generation in human neutrophils.
abstract: Three flavonoids, quercetin 3- O-glucoside-2''-gallate (QGG), quercetin 3- O-rhamnoside-2''-gallate (QRG) and kaempferol 3- O-glucoside-2''-gallate (KGG) were isolated from Japanese Polygonum species. The effect of these flavonoids on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of cytochrome c. The tyrosyl or serine/threonine phosphorylation of neutrophil proteins and the translocation of p4(phox) and p67(phox) to the cell membrane were detected using specific monoclonal antibodies. The flavonoids used in this experiment significantly suppressed stimulus-induced superoxide generation in a concentration-dependent manner. FMLP-induced tyrosyl phosphorylation or PMA-induced serine/threonine phosphorylation and the translocation of the cytosolic proteins p47(phox) and p67(phox) to the cell membrane were suppressed in parallel to the suppression of the stimulus-induced superoxide generation.
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Kochi Medical School, Nankoku-shi, Kochi 783-8505, Japan.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.forename: Weifang
authors.initials: W
authors.lastname: Wang
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Masuoka
authors.forename: Takahiko
authors.initials: T
authors.lastname: Isobe
authors.forename: Koichi
authors.initials: K
authors.lastname: Yamashita
authors.forename: Masanobu
authors.initials: M
authors.lastname: Manabe
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kodama
mesh_terms: D029748:Caryophyllaceae; D002462:Cell Membrane / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007564:Japan; D008519:Medicine, Traditional; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism; D010766:Phosphorylation; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D021381:Protein Transport / Q000187:drug effects; D013481:Superoxides / Q000378:metabolism*
chemical_list: D005419:Flavonoids; D010936:Plant Extracts; D013481:Superoxides