title: Purpurogallin is a more powerful protector of kidney cells than Trolox and allopurinol.
abstract: Phase contrast and electron microscopic experiments demonstrated that oxyradicals generated with xanthine oxidase and hypoxanthine markedly damage rat kidney mesangial and porcine tubular epithelial cells. Purpurogallin, a phenol found in oak nutgalls, prolongs survival of the xanthine oxidase exposed renal cells three- to nine-fold longer than those without purpurogallin present. At levels equimolar to purpurogallin, either Trolox or allopurinol is less effective in delaying cell necrosis. Purpurogallin scavenges not only xanthine oxidase generated oxyradicals, but also non-enzymatically produced peroxyl radicals, more actively than equimolar levels of Trolox or allopurinol. Purpurogallin inhibits xanthine oxidase with severalfold higher potency than allopurinol and its more active metabolite oxypurinol. Therefore, purpurogallin is a stronger antioxidant than Trolox and a more potent inhibitor of xanthine oxidase than allopurinol as well as oxypurinol.
authors: Department of Clinical Biochemistry, University of Toronto, Ont., Canada.
authors: L H
authors: LH
authors: Zeng
authors: T W
authors: TW
authors: Wu
mesh_terms: D000493:Allopurinol / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001567:Benzocycloheptenes / Q000494:pharmacology*; D002478:Cells, Cultured; D002839:Chromans / Q000494:pharmacology*; D004912:Erythrocytes / Q000187:drug effects; D016166:Free Radical Scavengers; D005609:Free Radicals; D005920:Glomerular Mesangium / Q000166:cytology / Q000187:drug effects*; D007684:Kidney Tubules / Q000166:cytology / Q000187:drug effects*; D010100:Oxygen / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D010117:Oxypurinol / Q000494:pharmacology; D051381:Rats; D013552:Swine; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors / Q000633:toxicity
chemical_list: D000975:Antioxidants; D001567:Benzocycloheptenes; D002839:Chromans; D016166:Free Radical Scavengers; D005609:Free Radicals; D000493:Allopurinol; D014969:Xanthine Oxidase; D010117:Oxypurinol; C026133:purpurogallin; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; D010100:Oxygen