title: Effects of rhubarb tannins on uremic toxins.
abstract: The effects of each of several tannins purified from Rhei Rhizoma on serum constituents were investigated in rats with adenine-induced renal failure. Blood levels of urea nitrogen, methylguanidine (MG), and guanidinosuccinic acid (GSA) were significantly decreased in rats given (-)-epicatechin 3-O-gallate at a dose of 2.5, 5 or 10 mg/kg body weight/day for 24 days. The creatinine (Cr) level was also significantly decreased in rats given 5 and 10 mg of this compound. A significant decrease in urea nitrogen, MG, and GSA was found in rats given 6.25 mg of procyanidin B-2 3,3'-di-O-gallate. However, unlike the former two components the administration of 12.5 mg of procyanidin C-1 3,3',3''-tri-O-gallate produced a considerable or significant increase in bLood levels of urea nitrogen, Cr, MG, and GSA. RG-tannin had a weaker overall effect on serum constituents except for GSA in comparison with the corresponding effect of (-)-epicatechin 3-O-gallate and 6.25 mg of procyanidin B-2 3,3'-di-O-gallate. Rhatannin tended to increase the serum nitrogen constituents.
authors.affiliation: Department of Applied Biochemistry, Toyama Medical and Pharmaceutical University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yokozawa
authors.forename: K
authors.initials: K
authors.lastname: Fujioka
authors.forename: H
authors.initials: H
authors.lastname: Oura
authors.forename: G
authors.initials: G
authors.lastname: Nonaka
authors.forename: I
authors.initials: I
authors.lastname: Nishioka
mesh_terms: D000818:Animals; D044946:Biflavonoids; D001806:Blood Urea Nitrogen; D002392:Catechin / Q000031:analogs & derivatives / Q000627:therapeutic use; D003404:Creatinine / Q000097:blood; D004365:Drugs, Chinese Herbal / Q000302:isolation & purification / Q000627:therapeutic use; D006146:Guanidines / Q000097:blood; D008297:Male; D008760:Methylguanidine / Q000097:blood; D010946:Plants, Medicinal; D044945:Proanthocyanidins; D051381:Rats; D011919:Rats, Inbred Strains; D012250:Rheum; D013329:Structure-Activity Relationship; D013386:Succinates / Q000097:blood; D013634:Tannins / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use*; D014118:Toxins, Biological / Q000097:blood*; D014511:Uremia / Q000097:blood / Q000188:drug therapy*
chemical_list: D044946:Biflavonoids; D004365:Drugs, Chinese Herbal; D006146:Guanidines; D044945:Proanthocyanidins; D013386:Succinates; D013634:Tannins; D014118:Toxins, Biological; C479578:procyanidin B; C479583:procyanidin C; D008760:Methylguanidine; C001318:guanidinosuccinic acid; C039708:rhatannin; D002392:Catechin; C062669:epicatechin gallate; D003404:Creatinine