Early pharmacological inhibition of angiotensin-I converting enzyme activity induces obesity in adulthood.

We have investigated early programming of body mass in order to understand the multifactorial etiology of obesity. Considering that the renin-angiotensin system (RAS) is expressed and functional in the white adipose tissue (WAT) and modulates its development, we reasoned whether early transitory inhibition of angiotensin-I converting enzyme activity after birth could modify late body mass development. Therefore, newborn Wistar rats were treated with enalapril (10 mg/kg of body mass) or saline, starting at the first day of life until the age of 16 days. Between days ninetieth and hundred and eightieth, a group of these animals received high fat diet (HFD). Molecular, biochemical, histological, and physiological data were collected. Enalapril treated animals presented hyperphagia, overweight, and increased serum level of triglycerides, total cholesterol and leptin, in adult life. Body composition analyses revealed higher fat mass with increased adipocyte size in these animals. Molecular analyses revealed that enalapril treatment increases neuropeptide Y (NPY) and cocaine- and amphetamine-regulated transcript (CART) gene expression in hypothalamus, fatty acid synthase (FAS), and hormone-sensitive lipase (HSL) gene expression in retroperitoneal WAT, and decreases peroxixome proliferators-activated receptor (PPAR)γ, PPARα, uncoupling protein (UCP)2, and UCP3 gene expression in WAT. The results of the current study indicate that enalapril administration during early postnatal development increases body mass, adiposity and serum lipids in adulthood associated with enhanced food intake and decreased metabolic activity in WAT, predisposing to obesity in adulthood.

Iron absorption from infant formula and iron-fortified cow's milk: experimental model in weanling rats.

OBJECTIVE: To compare iron absorption from infant formula and iron-fortified cow's milk. METHODS: Twenty-four weanling Wistar rats were maintained in metabolic cages during the whole experiment (10 days). On the first day, the animals were divided into three similar groups according to their weight, length, hematocrit and hemoglobin levels: 1) infant formula; 2) powdered whole cow's milk fortified with iron in the same quantity and type as the formula; 3) control--powdered whole cow's milk not fortified with iron. Deionized water and diet were offered ad libitum and the volume consumed was measured. Weight, hematocrit, and hemoglobin levels were measured on the fifth and 10th days when length, fecal occult blood, and hepatic iron levels were also analyzed. RESULTS: Group 1 consumed less diet (450.5+/-26.50 mL) than group 2 (658.8+/-53.73 mL) and control group (532.7+/-19.06 mL, p < 0.001). Hemoglobin levels were higher (p < 0.001) in group 1 (12.1+/-1.13 g/dL) than in group 2 (9.6+/-1.59 g/dL) and in control group (6.2+/-0.97 g/dL). Hepatic iron level showed the same pattern as hemoglobin (p < 0.001). There was no difference in weight and length between the three groups (p = 0.342). There was no fecal occult blood in the any of the animals. CONCLUSIONS: Despite the lower volume consumed, the group that received formula presented higher iron absorption and hemoglobin levels than the group fed with fortified whole cow's milk. Growth was similar in the three groups.

Absorção do ferro da fórmula para lactentes e do leite de vaca fortificado: modelo experimental em ratos recém-desmamados / Iron absorption from infant formula and iron-fortified cow's milk: experimental model in weanling rats

OBJETIVO: Comparar a absorção do ferro da fórmula de partida e do leite de vaca integral fortificado. MÉTODOS: Foram utilizados 24 ratos machos Wistar recém-desmamados, mantidos em gaiolas metabólicas durante todo o período do experimento (10 dias). No primeiro dia, os animais foram distribuídos em três grupos semelhantes quanto ao peso, comprimento, hematócrito e hemoglobina: 1) fórmula de partida para lactentes; 2) leite de vaca integral em pó fortificado com a mesma quantidade e tipo de sal de ferro da fórmula; e 3) controle - leite de vaca integral em pó não fortificado com ferro. Água e dieta foram oferecidas ad libitum com mensuração do volume consumido. Peso, hematócrito e hemoglobina foram mensurados no quinto e no 10º dia do experimento, quando foram analisados também comprimento, sangue oculto nas fezes e teor de ferro hepático. RESULTADOS: O grupo 1 ingeriu menor volume de dieta (450,5±26,50 mL) que os grupos 2 (658,8±53,73 mL) e controle (532,7±19,06 mL; p < 0,001). As concentrações de hemoglobina foram maiores (p < 0,001) no grupo 1 (12,1±1,13 g/dL) que nos grupos 2 (9,6±1,59 g/dL) e controle (6,2±0,97 g/dL). O teor de ferro hepático apresentou o mesmo comportamento da hemoglobina (p < 0,001). Não foi observada diferença de peso e comprimento nos três grupos (p = 0,342). Não foi detectado sangue oculto nas fezes de nenhum dos animais. CONCLUSÕES: Apesar do menor volume ingerido, o grupo que recebeu fórmula apresentou maior absorção de ferro e concentração de hemoglobina que o grupo que recebeu leite de vaca integral fortificado. O crescimento foi semelhante nos três grupos.

OBJECTIVE: To compare iron absorption from infant formula and iron-fortified cow's milk. METHODS: Twenty-four weanling Wistar rats were maintained in metabolic cages during the whole experiment (10 days). On the first day, the animals were divided into three similar groups according to their weight, length, hematocrit and hemoglobin levels: 1) infant formula; 2) powdered whole cow's milk fortified with iron in the same quantity and type as the formula; 3) control - powdered whole cow's milk not fortified with iron. Deionized water and diet were offered ad libitum, and the volume consumed was measured. Weight, hematocrit, and hemoglobin levels were measured on the fifth and 10th days when length, fecal occult blood, and hepatic iron levels were also analyzed. RESULTS: Group 1 consumed less diet (450.5±26.50 mL) than group 2 (658.8±53.73 mL) and control group (532.7±19.06 mL, p < 0.001). Hemoglobin levels were higher (p < 0.001) in group 1 (12.1±1.13 g/dL) than in group 2 (9.6±1.59 g/dL) and in control group (6.2±0.97 g/dL). Hepatic iron level showed the same pattern as hemoglobin (p < 0.001). There was no difference in weight and length between the three groups (p = 0.342). There was no fecal occult blood in the any of the animals. CONCLUSIONS: Despite the lower volume consumed, the group that received formula presented higher iron absorption and hemoglobin levels than the group fed with fortified whole cow's milk. Growth was similar in the three groups.