Low-Protein Diet during Lactation and Maternal Metabolism in Rats.

Some metabolic alterations were evaluated in Wistar rats which received control or low-protein (17%; 6%) diets, from the pregnancy until the end of lactation: control non-lactating (CNL), lactating (CL), low-protein non-lactating (LPNL) and lactating (LPL) groups. Despite the increased food intake by LPL dams, both LP groups reduced protein intake and final body mass was lower in LPL. Higher serum glucose occurred in both LP groups. Lactation induced lower insulin and glucagon levels, but these were reduced by LP diet. Prolactin levels rose in lactating, but were impaired in LPL, followed by losses of mammary gland (MAG) mass and, a fall in serum leptin in lactating dams. Lipid content also reduced in MAG and gonadal white adipose tissue of lactating and, in LPL, contributed to a decreased daily milk production, and consequent impairment of body mass gain by LPL pups. Liver mass, lipid content and ATP-citrate enzyme activity were increased by lactation, but malic enzyme and lipid: glycogen ratio elevated only in LPL. Conclusion. LP diet reduced the development of MAG and prolactin secretion which compromised milk production and pups growth. Moreover, this diet enhanced the store of lipid to glycogen ratio and suggests a higher risk of fatty liver development.

Nutritional recovery with rice bran did not modify energy balance and leptin and insulin levels.

OBJECTIVE: To investigate the effect of nutritional recovery with rice bran on energy balance, leptin and insulin levels. METHODS: Weaned Wistar rats were fed on a 17% (Control - C) or 0.5% (Aproteic - A) protein diet for 12d. After this, rats were kept on a C diet (C) or recovered with control (Recovered Control - RC) or control plus recovered rice bran diet (Recovered Rice Bran - RRB). RESULTS: Despite the increased food intake, group A exhibited lower carcass fat associated to low serum leptin. RRB and RC groups showed lower carcass weight and energy intake and expenditure. Energy expenditure was positively associated with food intake and carcass weight. Negative correlations between HOMA-IR and energy expenditure and energy intake were observed. CONCLUSION: Nutritional recovery with rice bran did not modify energy balance, leptin and insulin levels.

Nutritional recovery with rice bran did not modify energy balance and leptin and insulin levels / Recuperação nutricional com farelo de arroz não modificou o balanço energético e os níveis de leptina e insulina

OBJECTIVE: To investigate the effect of nutritional recovery with rice bran on energy balance, leptin and insulin levels. METHODS: Weaned Wistar rats were fed on a 17 percent (Control - C) or 0.5 percent (Aproteic - A) protein diet for 12d. After this, rats were kept on a C diet (C) or recovered with control (Recovered Control - RC) or control plus recovered rice bran diet (Recovered Rice Bran - RRB). RESULTS: Despite the increased food intake, group A exhibited lower carcass fat associated to low serum leptin. RRB and RC groups showed lower carcass weight and energy intake and expenditure. Energy expenditure was positively associated with food intake and carcass weight. Negative correlations between HOMA-IR and energy expenditure and energy intake were observed. CONCLUSION: Nutritional recovery with rice bran did not modify energy balance, leptin and insulin levels.

OBJETIVO: Investigar o efeito da recuperação nutricional com farelo de arroz sobre o balanço energético e níveis de leptina e insulina. MÉTODOS: Ratos Wistar recém-desmamados foram alimentados com 17 por cento (Controle - C) ou 0,5 por cento (Aproteico - A) de proteína (caseína) durante 12 dias. Em seguida, ratos permaneceram com dieta controle (C) ou foram recuperados com controle (Recuperados Controle - RC) ou controle mais 5 por cento de farelo de arroz (Recuperados com Farelo de Arroz - RFA) durante 21 dias. RESULTADOS: Apesar de a ingestão alimentar ter sido maior em A, a gordura na carcaça foi reduzida, sendo associada com menor nível de leptina. Os grupos RFA e RC tiveram redução no peso da carcaça, no gasto e ingestão de energia. O gasto energético foi correlacionado com a ingestão de alimentos e o peso da carcaça fresco. Foi observada correlação negativa entre HOMA-IR com gasto energético e com ingestão de energia. CONCLUSÃO: A recuperação nutricional com farelo de arroz não modificou o balanço energético, nem os níveis de leptina e insulina.

Effect of nutritional recovery with soybean flour diet on body composition, energy balance and serum leptin concentration in adult rats.

BACKGROUND: Malnutrition in early life is associated with obesity in adulthood and soybean products may have a beneficial effect on its prevention and treatment. This study evaluated body composition, serum leptin and energy balance in adult rats subjected to protein restriction during the intrauterine stage and lactation and recovering on a soybean flour diet. METHODS: Five groups of the Wistar strain of albino rats were used: CC, offspring born to and suckled by mothers fed a control diet and fed the same diet after weaning; CS, offspring born to and suckled by mothers fed a control diet and fed a soybean diet with 17% protein after weaning; LL, offspring of mothers fed a low protein diet and fed the same diet after weaning; LC, offspring of mothers fed a low protein diet, but fed a control diet after weaning; LS, offspring of mothers fed a low protein diet, but fed a soybean diet with 17% protein after weaning. Food intake, body, perirenal and retroperitoneal adipose tissue were measured in grams. Leptin was quantified using the Enzyme Linked Immuno Sorbent Assay (ELISA) and insulin by radioimmunoassay (RIA). Carcass composition was determined by chemical methods and energy expenditure was calculated by the difference between energy intake and carcass energy gain. Data were tested by analysis of variance (ANOVA). RESULTS: The LC and LS groups had higher energetic intake concerning body weight, lower energy expenditure, proportion of fat carcass and fat pads than CC and CS groups. The LS group showed reduced body weight gain and lower energy efficiency, which was reflected in less energy gain as protein and the proportion of carcass protein, and lower energy gain as lipid than in the LC groups, although both groups had eaten the same amount of diet and showed equal energy expenditure. Serum leptin did not differ among groups and was unrelated to food or energy intake and energy expenditure. Serum insulin was higher in the LS than in the LC group. CONCLUSION: Protein restriction during intrauterine life and lactation periods did not provoke obesity in adulthood. Nutritional recovery with soybean diet decreased the body weight at the expense of lower energy efficiency with repercussion on lean mass.

[Protein restriction in pregnancy: effects related to dam metabolism]. / Restrição protéica na prenhez: efeitos relacionados ao metabolismo materno.

Metabolism alterations were evaluated in female Wistar rats (dams) during pregnancy. Pregnant and non-pregnant dams submitted to protein restriction, were fed isocaloric (15.74 kJ/g), control or hypoproteic (17% vs. 6%) diets, and distributed in four Groups (n=7) as follows: non-pregnant control (NPC), pregnant control (PC), non-pregnant hypoproteic (NPH), and pregnant hypoproteic (PH); from Day 1 to Day 18 of pregnancy. Biochemical, hormonal and metabolic parameters related to lipid synthesis were assessed. The two-way ANOVA, followed by Tukey-HSD and Student-t tests were used, with a significance of p< 0.05. Protein restriction elevated lipid synthesis and malic enzyme (ME) activity in the liver, and reduced mass and the lipid/glycogen ratio in this tissue; it also lowered protein ingestion (total and %), lipid content (%) in the mammary gland (MAG), serum proteins and albumin, with consequent reduction of placenta and fetal masses. Pregnancy reduced serum protein and albumin concentrations, lipid synthesis, ME activity, hepatic lipid and glycogen content. However, it increased final body mass; increased relative masses of gonad (GON), liver and MAG; but reduced lipid synthesis and content of GON, lipid content of MAG and the relative mass of carcass. Pregnancy Insulinemia increased during pregnancy with reduced glycemia, characterizing hormonal resistance. Leptin and prolactin were also increased during pregnancy, being the highest increase in observed in HP rats. Protein restriction in pregnancy modified maternal metabolism, altering lipid synthesis in the liver and hormonal profile and decreasing the placenta and fetus masses.

Restrição protéica na prenhez: efeitos relacionados ao metabolismo materno / Protein restriction in pregnancy: effects related to dam metabolism

Foram avaliadas as alterações no metabolismo materno durante a prenhez em ratas Wistar, prenhes e não-prenhes, submetidas à restrição protéica, que receberam dietas isocalóricas (15,74 kJ/g), controle ou hipoprotéica (17 por cento versus 6 por cento), distribuídas em quatro grupos (n = 7), quais sejam: controle não-prenhe (CNP) e prenhe (CP) e hipoprotéico não-prenhe (HNP) e prenhe (HP), do 1º ao 18º dia de prenhez. Parâmetros bioquímicos, hormonais e relacionados à síntese de lipídios foram considerados. Utilizou-se ANOVA a duas vias seguido de teste Tukey-HSD e teste t de Student, significância de p < 0,05. A restrição protéica elevou a síntese de lipídios e a atividade da enzima málica (EM) no fígado (FIG) e reduziu a massa ( por cento) e a razão lipí+dio/glicogênio nesse tecido, bem como reduziu a ingestão protéica (total e por cento), o conteúdo ( por cento) de lipídios na glândula mamária (GMA), as proteínas e a albumina séricas, com consequente redução nas massas da placenta e fetos. A prenhez reduziu a proteinemia, a albuminemia, a síntese de lipídios, a atividade da EM, os lipídios e o glicogênio no FIG. Mas elevou a massa corporal final, a massa ( por cento) do tecido adiposo gonadal (GON), do FIG e da GMA, e reduziu a massa ( por cento) da carcaça (CARC), a síntese e o conteúdo de lipídios no GON e, na GMA, o conteúdo de lipídios. A insulinemia elevou-se na prenhez, com glicemia reduzida, caracterizando resistência hormonal. A leptina e a prolactina também se elevaram na prenhez, sendo o aumento maior no HP. A restrição protéica na prenhez modificou o metabolismo materno, alterando a síntese de lipídios no FIG e o perfil hormonal, além de reduzir a massa da placenta e dos fetos.

Metabolism alterations were evaluated in female Wistar rats (dams) during pregnancy. Pregnant and non-pregnant dams submitted to protein restriction, were fed isocaloric (15.74 kJ/g), control or hypoproteic (17 percent vs. 6 percent) diets, and distributed in four Groups (n=7) as follows: non-pregnant control (NPC), pregnant control (PC), non-pregnant hypoproteic (NPH), and pregnant hypoproteic (PH); from Day 1 to Day 18 of pregnancy. Biochemical, hormonal and metabolic parameters related to lipid synthesis were assessed. The two-way ANOVA, followed by Tukey-HSD and Student-t tests were used, with a significance of p< 0.05. Protein restriction elevated lipid synthesis and malic enzyme (ME) activity in the liver, and reduced mass and the lipid/glycogen ratio in this tissue; it also lowered protein ingestion (total and percent), lipid content ( percent) in the mammary gland (MAG), serum proteins and albumin, with consequent reduction of placenta and fetal masses. Pregnancy reduced serum protein and albumin concentrations, lipid synthesis, ME activity, hepatic lipid and glycogen content. However, it increased final body mass; increased relative masses of gonad (GON), liver and MAG; but reduced lipid synthesis and content of GON, lipid content of MAG and the relative mass of carcass. Pregnancy Insulinemia increased during pregnancy with reduced glycemia, characterizing hormonal resistance. Leptin and prolactin were also increased during pregnancy, being the highest increase in observed in HP rats. Protein restriction in pregnancy modified maternal metabolism, altering lipid synthesis in the liver and hormonal profile and decreasing the placenta and fetus masses.

Associação de glutamina e probióticos no trofismo mucoso do cólon na peritonite experimental / Association of glutamine and probiotics on the colonic mucosal trophism in experimental peritonitis

OBJETIVO: O objetivo deste estudo foi investigar o efeito da associação da glutamina e probióticos sobre a mucosa intestinal em ratos submetidos à peritonite experimental. MÉTODO: 16 ratos Wistar (250-350g) com peritonite experimental criada pelo método da punção dupla do ceco foram randomizados para receber diariamente no pós-operatório em conjunto com a dieta, a adição por gavagem de 0,500g de glutamina e leite reconstituído, contendo probióticos (10(6) unidades formadoras de colônias/g de Bifidobacterium lactis BL e Streptococcus thermophilus) (grupo glutamina-probióticos; n=8) ou 0,495g de caseína e leite reconstituído sem probióticos (grupo controle; n=8). O conteúdo das duas dietas foi isonitrogenado e isocalórico. Todos os animais foram sacrificados 120 horas após a peritonite experimental. A profundidade de criptas e espessura de parede da mucosa do cólon foram medidas em biopsias realizadas 2 cm acima da reflexão peritoneal. O restante da mucosa colônica foi pesado e nela mensurou-se o conteúdo de DNA. RESULTADOS: Os animais que receberam glutamina e probióticos apresentaram mucosa mais pesada (0,49±0,12 vs. 0,42±0,07g; p=0,02), maior conteúdo de DNA (0,31±0,07 vs. 0,22±0,05 mg/g de tecido; p<0,01) e criptas mais profundas (272±51 vs. 311±39æ; p=0,04) que o grupo controle. CONCLUSÃO: A associação da glutamina e probióticos confere um maior trofismo na mucosa colônica em ratos submetidos à peritonite experimental.

BACKGROUND: The aim of this study was to investigate the effect of the association of glutamine and probiotics on the colonic mucosal trophism in experimental peritonitis. METHOD: 16 Wistar rats (250-350g) with experimental peritonitis created by double cecal puncture were randomized to receive postoperatively in conjunction with rat chow the daily gavages of either 0,500g of glutamine and reconstituted milk containing probiotics (10(6) colony-forming units/g of Bifidobacterium lactis BL and Streptococcus thermophilus) (glutamine-probiotics group; n=8) or 0,495g of caseine and reconstituted milk without probiotics (control group; n=8). The contents of the two diets were isonitrogenous and isocaloric. All animals were killed 120h after the creation of the peritonitis. Crypt depth and wall width of the colonic mucosa were registered in biopsies taken 2 cm above peritoneal reflexion. The rest of the colonic mucosa was weighted and assayed for DNA content. RESULTS: Animals receiving glutamine ans probióticos presented greater mucosal weight (0,49±0,12 vs. 0,42±0,07g; p=0,02), DNA content (0,31±0,07 vs 0,22±0,05 mg/g de tecido; p<0,01) e deeper crypts (272±51 vs. 311±39æ; p=0,04) than controls. CONCLUSION: The association of glutamine and probiotics enhances colonic mucosal trophism in rats under experimental peritonitis.