title: Manganese status, gut endogenous losses of manganese, and antioxidant enzyme activity in rats fed varying levels of manganese and fat.
abstract: We hypothesized that manganese deficient animals fed high vs moderate levels of polyunsaturated fat would either manifest evidence of increased oxidative stress or would experience compensatory changes in antioxidant enzymes and/or shifts in manganese utilization that result in decreased endogenous gut manganese losses. Rats (females in Study 1, males in Study 2, n = 8/treatment) were fed diets that contained 5 or 20% corn oil by weight and either 0.01 or 1.5 mumol manganese/g diet. In study 2, 54Mn complexed to albumin was injected into the portal vein to assess gut endogenous losses of manganese. The manganese deficient rats: 1. Had 30-50% lower liver, tibia, kidney, spleen, and pancreas manganese concentrations than manganese adequate rats; 2. Conserved manganese through approximately 70-fold reductions in endogenous fecal losses of manganese; 3. Had lower heart manganese superoxide dismutase (MnSOD) activity; and 4. Experienced only two minor compensatory changes in the activity of copper-zinc superoxide dismutase (CuZnSOD) and catalase. Gut endogenous losses of manganese tended to account for a smaller proportion of absorbed manganese in rats fed high-fat diets; otherwise fat intake had few effects on tissue manganese concentrations.
authors.affiliation: Department of Nutritional Sciences, University of Wisconsin, Madison 53706.
authors.forename: E A
authors.initials: EA
authors.lastname: Malecki
authors.forename: D L
authors.initials: DL
authors.lastname: Huttner
authors.forename: J L
authors.initials: JL
authors.lastname: Greger
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001842:Bone and Bones / Q000378:metabolism; D002374:Catalase / Q000378:metabolism*; D003314:Corn Oil; D004032:Diet; D004041:Dietary Fats / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D007422:Intestines / Q000502:physiology*; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D008345:Manganese / Q000172:deficiency / Q000378:metabolism* / Q000494:pharmacology*; D009928:Organ Specificity; D018384:Oxidative Stress; D010179:Pancreas / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D012737:Sex Factors; D013154:Spleen / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism*; D013977:Tibia
chemical_list: D004041:Dietary Fats; D005231:Fatty Acids, Unsaturated; D008345:Manganese; D003314:Corn Oil; D002374:Catalase; D013482:Superoxide Dismutase