Hydrogen Produced In Rat Colon Improves In Vivo Reduction-Oxidation Balance Due To Induced Regeneration Of Alpha-Tocopherol

We investigated whether non-digestible saccharide fermentation-derived hydrogen molecules (H-2) in rat colon could improve the in vivo reduction-oxidation (redox) balance via regeneration of alpha-tocopherol, by assessing their effect on hydroxyl radicals, the alpha-tocopherol concentration and the redox balance. In Expt 1, a Fenton reaction with phenylalanine (0 or 1 center dot 37 mmol/l of H-2) was conducted. In Expt 2, rats received intraperitoneally maize oil containing phorone (400 mg/kg) 7 d after drinking ad libitum water containing 0 or 4 % fructo-oligosaccharides (FOS) (groups CP and FP, respectively). In Expt 3, rats unable to synthesise ascorbic acid drank ad libitum for 14 d water with 240 mg ascorbic acid/l (group AC), 20 mg of ascorbic acid/l (group DC) or 20 mg of ascorbic acid/l and 4 % FOS (group DCF). In the Fenton reaction, H-2 reduced tyrosine produced from phenylalanine to 72 % when platinum was added and to 92 % when platinum was excluded. In Expt 2, liver glutathione was depleted by administration of phorone to rats. However, compared with CP, no change in the m-tyrosine concentration in the liver of FP was detected. In Expt 3, net H-2 excretion was higher in DCF than in the other rats after 3 d of the experiment. Furthermore, the concentrations of H-2 and alpha-tocopherol and the redox glutathione ratio in perirenal adipose tissue of rats were significantly higher in DCF than in DC. To summarise, in rat colon, fermentation-derived H-2 further shifted the redox balance towards a more reducing status in perirenal adipose tissue through increased regeneration of alpha-tocopherol.