title: Effects of age, dietary restriction and germ-free environment on glutathione-related enzymes in Lobund-Wistar rats.
abstract: The effects of age, dietary restriction and germ-free environment on glutathione peroxidase (GP), glutathione reductase (GR) and glutathione-S-transerases (GT) were studied in 48 Lobund-Wistar male rats obtained through the Lobund Aging Study. The treatment design was a 2 x 2 x 3 factorial design (environment x food level x age). Four rats were killed at 6, 18 and 30 months for each of the following groups of rats: conventional ad libitum (CV-A), conventional restricted (CV-R), germ-free ad libitum (GF-A) and germ-free restricted (GF-R). The dietary restriction (DR) was 30%. The activities of the three enzymes in the liver cytosolic fraction were determined. The activities of DR and GT were not affected by age, and were significantly lower in the rats raised in the GF environment than in those raised in the CV environment. DR significantly increased GR in the GF environment. The total GP activity was not affected by age but significantly increased by DR and a GF environment, suggesting that these life prolonging conditions provide greater protection against organic hydroperoxides and low concentrations of hydrogen peroxide.
authors.affiliation: Department of Nutrition and Food Sciences, University of Kentucky, Lexington, KY 40506-0054, U.S.A.
authors.forename: L H
authors.initials: LH
authors.lastname: Chen
authors.forename: D L
authors.initials: DL
authors.lastname: Snyder