A Phytoestrogen-Rich Diet Increases Energy Expenditure and Decreases Adiposity in Mice

• Published in: Environmental health perspectives Vol. 115; no. 10; pp. 1467 - 1473
• Main Authors: Christopher R. Cederroth, Manlio Vinciguerra, Françoise Kühne, Rime Madani, Doerge, Daniel R., Visser, Theo J., Foti, Michelangelo, Françoise Rohner-Jeanrenaud, Vassalli, Jean-Dominique, Nef, Serge
• Format: Journal Article
• Language: English
• Published: United States National Institute of Environmental Health Sciences. National Institutes of Health. Department of Health, Education and Welfare 01.10.2007; National Institute of Environmental Health Sciences
• Subjects: Adipose tissues; Adiposity - drug effects; Agouti-Related Protein - drug effects; Animal Feed; Animals; Bioenergetics; Body weight; Case-Control Studies; Cold Temperature; Energy metabolism; Energy Metabolism - drug effects; Estrogens; Evaluation; Glycine max - chemistry; Health aspects; Influence; Isoflavones; Isoflavones - blood; Isoflavones - pharmacology; Lipid metabolism; Lipid Peroxidation - drug effects; Lipids; Locomotion; Male; Mice; Obesity; Phytoestrogens; Phytoestrogens - metabolism; Phytoestrogens - pharmacology; United States; Switzerland; lipid oxidation; AgRP; phytoestrogens; isoflavones; obesity; endocrine disruptors
• ISSN: 0091-6765; 1552-9924
• DOI: 10.1289/ehp.10413

Background: Obesity is an increasingly prevalent health problem, and natural effective therapeutic approaches are required to prevent its occurrence. Phytoestrogens are plant-derived compounds with estrogenic activities; they can bind to both estrogen receptors α and β and mimic the action of estrogens on target organs. Objectives: The purpose of this study was to examine the influence of soy-derived phytoestrogens on energy balance and metabolism. Methods: Male outbred mice (CD-1) were allowed ad libitum access to either a high soy-containing diet or a soy-free diet from conception to adulthood. We measured circulating serum isoflavone levels using reverse-phase solid-phase extraction for subsequent liquid chromatography electrospray tandem mass spectrometry analysis. Adult animals were analyzed for body composition by dual-energy X-ray absorptiometry, locomotor activity by running-wheel experiments, respiratory exchange rate by indirect calorimetry, and food intake using metabolic cages. Quantitative reverse transcriptase-polymerase chain reaction was performed to determine the expression of hypothalamic neuropeptide genes. Results: We found that adult mice fed a soy-rich diet had reduced body weight, adiposity, and resistance to cold. This lean phenotype was associated with an increase in lipid oxidation due to a preferential use of lipids as fuel source and an increase in locomotor activity. The modulation of energy balance was associated with a central effect of phytoestrogens on the expression of hypothalamic neuropeptides, including agouti-related protein. Conclusion: The data suggest that dietary soy could have beneficial effects on obesity, but they also emphasize the importance of monitoring the phytoestrogen content of diets as a parameter of variability in animal experiments.