title: Brief communication: Effects of soy-protein diet on elevated brain lipid peroxide levels induced by simulated weightlessness.
abstract: The influence of soy-protein diet on brain lipid peroxidation in female rats was studied using a tail-suspension model of weightlessness. The study tested the efficacy of diets containing 0% or 11.1% soy-protein in 4 groups of female Sprague Dawley rats that were maintained with or without tail-suspension for a period of 3 weeks. At term, the whole brain was removed, segmented, and analyzed for malondialdehyde (MDA) as an index of lipid peroxidation. Brain levels of MDA were significantly higher in both tail-suspended groups than in the non-suspended control groups on the same diet, (p<0.05). The high soy-protein diet decreased MDA levels significantly, compared to the 0% soy-protein groups (p<0.05). Furthermore, MDA levels were significantly lower in the tail-suspended group on high soy-protein diet, compared to the corresponding 0% soy-protein group. In conjunction with previous findings in male rats, these data indicate that tail-suspension increases brain MDA levels in rats regardless of gender, and that a diet rich in soy-protein decreases the brain MDA level in both the non-suspended and tail-suspended groups. These observations imply that the soy-protein diet has a protective antioxidant effect during both the basal condition and the stressful condition.
authors.affiliation: Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Soulsby
authors.forename: Blake
authors.initials: B
authors.lastname: Phillips
authors.forename: Parimal
authors.initials: P
authors.lastname: Chowdhury
mesh_terms: D000821:Animal Feed; D000818:Animals; D001921:Brain / Q000378:metabolism*; D005260:Female; D019417:Hindlimb Suspension; D015227:Lipid Peroxidation / Q000502:physiology*; D008054:Lipid Peroxides / Q000378:metabolism*; D008315:Malondialdehyde / Q000032:analysis / Q000378:metabolism; D014674:Plant Proteins, Dietary / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D030262:Soybean Proteins / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D008054:Lipid Peroxides; D014674:Plant Proteins, Dietary; D030262:Soybean Proteins; D008315:Malondialdehyde