title: Pyridoxine-5'-beta-D-glucoside affects the metabolic utilization of pyridoxine in rats.
abstract: A major form of vitamin B-6 in plant-derived foods is pyridoxine-5'-beta-D-glucoside. Previous studies have shown that pyridoxine-5'-beta-D-glucoside is poorly available as a source of vitamin B-6 in rats and is partially utilized in humans. This research was conducted to determine whether unlabeled pyridoxine-5'-beta-D-glucoside affects the metabolic utilization of simultaneously administered isotopically labeled pyridoxine in rats. Three groups of rats (n = 6) were administered a single oral dose of 0, 36 or 72 nmol of unlabeled pyridoxine-5'-beta-D-glucoside along with 166.5 MBq (240 nmol) of [14C]pyridoxine. Twenty-four hours after administration of the dose the rats were killed, and the isotopic distribution of vitamin B-6 metabolites in liver and urine was determined. Urinary 14C and hepatic 14C-labeled pyridoxine phosphate and pyridoxal phosphate were directly related to pyridoxine-5'-beta-D-glucoside dose. Hepatic 14C, 14C-labeled pyridoxal, pyridoxine and pyridoxamine, and the concentration of urinary [14C]4-pyridoxic acid, relative total urinary 14C, were inversely proportional to the dose of pyridoxine-5'-beta-D-glucoside. These results provide evidence that pyridoxine-5'-beta-D-glucoside quantitatively alters the metabolism and in vivo retention of [14C]pyridoxine and that pyridoxine-5'-beta-D-glucoside may retard the utilization of nonglycosylated forms of vitamin B-6.
authors.affiliation: Food Science and Human Nutrition Department, University of Florida, Gainesville 32611-0163.
authors.forename: J A
authors.initials: JA
authors.lastname: Gilbert
authors.forename: J F
authors.initials: JF
authors.lastname: Gregory
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D005960:Glucosides; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D011736:Pyridoxine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000378:metabolism* / Q000493:pharmacokinetics / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D005960:Glucosides; C022945:5'-O-(glucopyranosyl)pyridoxine; D011736:Pyridoxine