Impact of glutathione supplementation of parenteral nutrition on hepatic methionine adenosyltransferase activity

• Published in: Redox biology 2016-08, Vol.8 (C), p.18-23
• Main Authors: Elremaly, Wesam, Mohamed, Ibrahim, Rouleau, Thérèse, Lavoie, Jean-Claude
• Format: Article
• Language: English
• Subjects: Animals; Biomarkers; Dietary Supplements; Enzyme Activation - drug effects; Glutathione - metabolism; Glutathione Disulfide - metabolism; Guinea Pigs; Liver - drug effects; Liver - metabolism; Methionine adenosyltransferase; Methionine Adenosyltransferase - metabolism; Newborn; Oxidation-Reduction - drug effects; Oxidative Stress - drug effects; Parenteral Nutrition; Parenteral Nutrition Solutions - pharmacology; Peroxide; Peroxides - metabolism; Redox potential of glutathione; Research Paper; Thiol oxidation
• ISSN: 2213-2317; 2213-2317
• DOI: 10.1016/j.redox.2015.12.003

The oxidation of the methionine adenosyltransferase (MAT) by the combined impact of peroxides contaminating parenteral nutrition (PN) and oxidized redox potential of glutathione is suspected to explain its inhibition observed in animals. A modification of MAT activity is suspected to be at origin of the PN-associated liver disease as observed in newborns. We hypothesized that the correction of redox potential of glutathione by adding glutathione in PN protects the MAT activity. To investigate whether the addition of glutathione to PN can reverse the inhibition of MAT observed in animal on PN. Three days old guinea pigs received through a jugular vein catheter 2 series of solutions. First with methionine supplement, (1) Sham (no infusion); (2) PN: amino acids, dextrose, lipids and vitamins; (3) PN-GSSG: PN+10μM GSSG. Second without methionine, (4) D: dextrose; (5) D+180μM ascorbylperoxide; (6) D+350μM H2O2. Four days later, liver was sampled for determination of redox potential of glutathione and MAT activity in the presence or absence of 1mM DTT. Data were compared by ANOVA, p