Choline‐related supplements improve altered abnormal plasma methionine‐homocysteine and glutathione status in children with Cystic Fibrosis

Abstract

Liver triglyceride accumulation is common in cystic fibrosis (CF), results in oxidative stress and is a characteristic feature of choline deficiency due to lack of choline for phosphatidylcholine (PC) synthesis via the CDP-choline. PC is formed from phosphatidylethanolamine using methyl groups from methionine via S-adenosylmethionine (SAM) with generation of S-adenosylhomocysteine (SAH). Previously we showed increased PC excretion, and increased plasma homocysteine and SAH, and decreased SAM/SAH in children with CF. In these studies we determined the relation between choline and methionine-homocysteine in children with CF supplemented with lecithin, 2g/d, n=13, choline, 2g/d n=10 or betaine 3g/d n=10 for 14 days. Plasma thiols and phospholipids were determined before and after supplementation, and in children without CF, n=15. Children with CF had significantly higher plasma homocysteine and SAH and lower methionine and SAM/ SAH and GSH/GSSG ratios than children without CF, P<0.05. Plasma methionine, SAM/SAH and GSH/GSSG ratios were significantly increased by supplementation with lecithin, choline and betaine, n=35. All the supplements increased the SAM/SAH, supplementation with choline increased GSH and GSH/GSSG ratio. We show that dietary supplementation aimed at increasing choline status improves altered thiol metabolism and may reduce oxidant stress in children with cystic fibrosis.