title: Choline-related supplements improve abnormal plasma methionine-homocysteine metabolites and glutathione status in children with cystic fibrosis.
abstract: BACKGROUND
  Liver triacylglycerol accumulation and oxidative stress are common in cystic fibrosis (CF) and also occur in choline deficiency. Previously, we showed an association between elevated plasma homocysteine, reduced ratios of S-adenosylmethionine to S-adenosylhomocysteine (SAM:SAH) and of phosphatidylcholine to phosphatidylethanolamine, and phospholipid malabsorption in children with CF.
  
  
  OBJECTIVE
  The objective was to address a possible relation between altered methionine-homocysteine metabolism and choline metabolism in children with CF.
  
  
  METHODS
  Children with CF were assigned without bias to supplementation with 2 g lecithin/d (n = 13), 2 g choline/d (n = 12), or 3 g betaine/d (n = 10) for 14 d. Plasma concentrations of methionine, adenosine, cysteine, cysteinyl-glycine, glutathione, glutathione disulfide (GSSG), and fatty acids; SAM:SAH; and red blood cell phospholipids were measured within each group of children with CF before and after supplementation. Plasma from healthy children without CF (n = 15) was analyzed to obtain reference data.
  
  
  RESULTS
  Children with CF had higher plasma homocysteine, SAH, and adenosine and lower methionine, SAM:SAH, and glutathione:GSSG than did children without CF. Supplementation with lecithin, choline, or betaine resulted in a significant increase in plasma methionine, SAM, SAM:SAH, and glutathione:GSSG and a decrease in SAH (n = 35). Supplementation with choline or betaine was associated with a significant decrease in plasma SAH and an increase in SAM:SAH, methionine, and glutathione:GSSG. Supplementation with lecithin or choline also increased plasma methionine and SAM.
  
  
  CONCLUSIONS
  We showed that dietary supplementation with choline-related compounds improves the low SAM:SAH and glutathione redox balance in children with CF.
authors.affiliation: Department of Paediatrics, University of British Columbia, Vancouver, BC, Canada. sinnis@cw.bc.ca
authors.forename: Sheila M
authors.initials: SM
authors.lastname: Innis
authors.forename: A George F
authors.initials: AG
authors.lastname: Davidson
authors.forename: Stepan
authors.initials: S
authors.lastname: Melynk
authors.forename: S Jill
authors.initials: SJ
authors.lastname: James
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002794:Choline / Q000627:therapeutic use*; D003550:Cystic Fibrosis / Q000097:blood* / Q000178:diet therapy*; D019587:Dietary Supplements; D005260:Female; D005978:Glutathione / Q000097:blood*; D019803:Glutathione Disulfide / Q000097:blood; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008715:Methionine / Q000097:blood*; D010713:Phosphatidylcholines / Q000627:therapeutic use*
chemical_list: D010713:Phosphatidylcholines; D006710:Homocysteine; D008715:Methionine; D005978:Glutathione; D002794:Choline; D019803:Glutathione Disulfide