title: Dietary withdrawal of phytoestrogens resulted in higher gene expression of 3-beta-HSD and ARO but lower 5-alpha-R-1 in male rats.
abstract: Removing dietary phytoestrogens causes obesity and diabetes in adult male rats. Based on the facts that hypothalamic food intake control is disrupted in phytoestrogen-deprived animals and that several steroids affect food intake, we hypothesized that phytoestrogen withdrawal alters the expression of hypothalamic steroidogenic enzymes. Male Wistar rats fed with a high-phytoestrogen diet from conception to adulthood were subjected to phytoestrogen withdrawal by feeding them a low-phytoestrogen diet or a high-phytoestrogen, high-fat diet. Withdrawal of dietary phytoestrogens increased 3β-hydroxysteroid dehydrogenase and P450 aromatase gene expression and decreased those of 5α-reductase-1. This is a direct effect of the lack of dietary phytoestrogens and not a consequence of obesity, as it was not observed in high-fat-fed rats. Phytoestrogen withdrawal and high-fat diet intake reduced hypothalamic expression of estrogen receptor (ER)α correlated with low levels of ERα-O, ERα-OS, and ERα-OT transcripts. Variations in gene expression of steroidogenic enzymes may affect the content of neurosteroids. As neurosteroids are related to food intake control, the changes observed may be a novel mechanism in the regulation of energy balance in obese phytoestrogen-deprived animals. In rats, steroidogenesis and ER signaling appear to be altered by phytoestrogen withdrawal in the rat. The ubiquity of phytoestrogens in the diet and changing intakes or withdrawal suggest that aspects of human health could be affected based on the rat and warrant further research.
authors.affiliation: Departamento de Bioquímica Clínica y Cuantitativa, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina; Instituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina.
authors.forename: María F
authors.initials: MF
authors.lastname: Andreoli
authors.affiliation: Departamento de Bioquímica Clínica y Cuantitativa, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina; Instituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina.
authors.forename: Cora
authors.initials: C
authors.lastname: Stoker
authors.affiliation: Departamento de Bioquímica Clínica y Cuantitativa, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina; Instituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina.
authors.forename: María F
authors.initials: MF
authors.lastname: Rossetti
authors.affiliation: Departamento de Bioquímica Clínica y Cuantitativa, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina; Instituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina.
authors.forename: Gisela P
authors.initials: GP
authors.lastname: Lazzarino
authors.affiliation: Instituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina.
authors.forename: Enrique H
authors.initials: EH
authors.lastname: Luque
authors.affiliation: Departamento de Bioquímica Clínica y Cuantitativa, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina; Instituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina. Electronic address: gramos@fbcb.unl.edu.ar.
authors.forename: Jorge G
authors.initials: JG
authors.lastname: Ramos
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D000818:Animals; D001069:Appetite Regulation; D001141:Aromatase / Q000378:metabolism*; D042944:Cholestenone 5 alpha-Reductase / Q000378:metabolism*; D004032:Diet; D059305:Diet, High-Fat; D004435:Eating / Q000502:physiology; D002149:Energy Intake; D047628:Estrogen Receptor alpha / Q000378:metabolism; D015870:Gene Expression; D007031:Hypothalamus / Q000378:metabolism; D008297:Male; D018377:Neurotransmitter Agents / Q000378:metabolism; D009765:Obesity / Q000209:etiology* / Q000378:metabolism; D048789:Phytoestrogens / Q000008:administration & dosage* / Q000494:pharmacology; D017208:Rats, Wistar; D015398:Signal Transduction
chemical_list: D047628:Estrogen Receptor alpha; D018377:Neurotransmitter Agents; D048789:Phytoestrogens; D015096:3-Hydroxysteroid Dehydrogenases; D001141:Aromatase; D042944:Cholestenone 5 alpha-Reductase
keywords: ERα; Hypothalamus; Obesity; Phytoestrogens; Steroidogenic enzymes