Metabolic utilization of pyridoxine-beta-glucoside in rats: influence of vitamin B-6 status and route of administration.
[3H]5'-O-(beta-D-glucopyranosyl) pyridoxine (PN-glucoside) and [14C]pyridoxine (PN) were administered orally or intraperitoneally to vitamin B-6-adequate or -deficient rats. Analysis of intestinal contents and feces indicated effective intestinal absorption of PN-glucoside relative to PN. There was greater retention of 14C than 3H in the liver and carcass regardless of the route of administration of the radiolabeled vitamins. There was no major difference in the relative distribution of 3H and 14C among the vitamin B-6 metabolites in the liver between the treatment groups, and no [3H]PN-glucoside was detected in any of the livers. For all groups, the majority of the 3H administered was detected in the urine within 24 h. Less excretion of both 3H and 14C in the urine was observed for the deficient rats. There was no major difference in the relative proportion of urinary [3H]PN-glucoside or [3H]4-PA between rats fed or injected with the radiolabeled vitamins. These results indicate that vitamin B-6 status influences the clearance of metabolites derived from PN and PN-glucoside, as well as the clearance of intact PN-glucoside. Vitamin B-6 status, however, has little or no effect on the utilization of PN-glucoside. This study also suggests that the intestine is the primary site of the limited conversion of PN-glucoside to biologically active PN in the rat.
Trumbo
P R
PR
Food Science and Human Nutrition Department, University of Florida, Gainesville 32611.
Gregory
J F
JF
D000284:Administration, Oral; D000818:Animals; D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D005960:Glucosides; D006868:Hydrolysis; D007274:Injections, Intraperitoneal; D007408:Intestinal Absorption; D008099:Liver / Q000378:metabolism; D008297:Male; D009753:Nutritive Value; D011736:Pyridoxine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014018:Tissue Distribution; D014316:Tritium; D026681:Vitamin B 6 Deficiency / Q000378:metabolism*
D002250:Carbon Radioisotopes; D005960:Glucosides; D014316:Tritium; C022945:5'-O-(glucopyranosyl)pyridoxine; D011736:Pyridoxine