title: Plasma choline concentration varies with different dietary levels of vitamins B6, B12 and folic acid in rats maintained on choline-adequate diets.
abstract: Choline is an important component of the human diet and is required for the endogenous synthesis of choline-containing phospholipids, acetylcholine and betaine. Choline can also be synthesised de novo by the sequential methylation of phosphatidylethanolamine to phosphatidylcholine. Vitamins B6, B12 and folate can enhance methylation capacity and therefore could influence choline availability not only by increasing endogenous choline synthesis but also by reducing choline utilisation. In the present experiment, we determined whether combined supplementation of these B vitamins affects plasma choline concentration in a rat model of mild B vitamin deficiency which shows moderate increases in plasma homocysteine. To this end, we measured plasma choline and homocysteine concentrations in rats that had consumed a B vitamin-poor diet for 4 weeks after which they were either continued on the B vitamin-poor diet or switched to a B vitamin-enriched diet for another 4 weeks. Both diets contained recommended amounts of choline. Rats receiving the B vitamin-enriched diet showed higher plasma choline and lower plasma homocysteine concentrations as compared to rats that were continued on the B vitamin-poor diet. These data underline the interdependence between dietary B vitamins and plasma choline concentration, possibly via the combined effects of the three B vitamins on methylation capacity.
authors.affiliation: Nutricia Advanced Medical Nutrition, Danone Research, Centre for Specialised Nutrition, PO Box 7005, 6700 CA Wageningen, The Netherlands. nick.vanwijk@danone.com
authors.forename: Nick
authors.initials: N
authors.lastname: van Wijk
authors.forename: Carol J
authors.initials: CJ
authors.lastname: Watkins
authors.forename: Mark
authors.initials: M
authors.lastname: Böhlke
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Maher
authors.forename: Robert J J
authors.initials: RJ
authors.lastname: Hageman
authors.forename: Patrick J G H
authors.initials: PJ
authors.lastname: Kamphuis
authors.forename: Laus M
authors.initials: LM
authors.lastname: Broersen
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Wurtman
mesh_terms: D000818:Animals; D001682:Biological Availability; D002794:Choline / Q000097:blood*; D004032:Diet; D019587:Dietary Supplements; D005492:Folic Acid / Q000494:pharmacology; D006710:Homocysteine / Q000097:blood*; D008297:Male; D008745:Methylation / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014805:Vitamin B 12 / Q000494:pharmacology; D025101:Vitamin B 6 / Q000494:pharmacology; D014803:Vitamin B Complex / Q000494:pharmacology*; D014804:Vitamin B Deficiency / Q000150:complications*
chemical_list: D006710:Homocysteine; D014803:Vitamin B Complex; D025101:Vitamin B 6; D005492:Folic Acid; D002794:Choline; D014805:Vitamin B 12