Short-term dietary magnesium restriction lowers spleen iron concentrations in growing rats fed a high-fat diet

Author(s)

De Carli, Eduardo ; Lobo, Alexandre R. ; Sales, Cristiane H. ; Teixeira, Pryscila D. S. ; Sales, Ana Lina de Carvalho C. ; Colli, Celia

• Document type: Journal article
• Source: LWT-FOOD SCIENCE AND TECHNOLOGY; v. 59, n. 2, p. 6-pg., 2014-12-01.

Abstract

Lipotoxicity and dietary inadequacies have been associated with dysregulation of Fe homeostasis in obesity. In this study, we tested the hypothesis that dietary Mg restriction in rats fed a high-fat diet affects Fe concentrations in liver and spleen, tissues related with Fe storage and recycling, respectively. Weanling male Wistar rats (n = 48) were fed either control (ad libitum or pair-fed) or high-fat (Mg-adequate or Mg-restricted; 500 and 150 mg Mg/kg, respectively) diets for 4 weeks. Epididymal and retroperitoneal fat pad weights were used to determine the adiposity index. Serum (colorimetry) and tissue Fe (atomic absorption spectrophotometry) were analyzed. Liver hepcidin was determined by qPCR and ferroportin-1 in liver and spleen was measured by immunoblotting. Dietary fat overload increased adiposity irrespective of dietary Mg levels. Rats fed the high-fat diet, but not those fed the high-fat Mg-restricted diet, had higher spleen Fe concentrations than controls. Weak but significant associations between body adiposity and serum (r = -0.31, P = 0.04) and spleen Fe (r = 0.29, P = 0.04) concentrations were obtained. The unaltered ferroportin-1 expression with low Fe levels suggests increased Fe recycling from spleen to bone marrow due to dietary Mg restriction. A longer study could clarify the consequences of these findings on erythropoiesis and other conditions related to diet-induced obesity. (C) 2014 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 11/08895-1 - Iron status in rats fed high-fat and magnesium-deficient diets: contribution of systemic inflammation and intestinal microenvironment
• Grantee: Alexandre Rodrigues Lobo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 09/05624-7 - Effect of dietary magnesium deficiency in the insulin resistance and in the inflammatory response in rats fed with high-fat diet
• Grantee: Cristiane Hermes Sales
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 10/05644-5 - Assessment of iron status in rats fed high-fat diets
• Grantee: Célia Colli
• Support Opportunities: Regular Research Grants