Different Protein Sources in the Maternal Diet of the Rat during Gestation and Lactation Affect Milk Composition and Male Offspring Development during Adulthood.

Protein sources in maternal diet are important for mammary gland differentiation and milk protein; however, few studies have examined the metabolic and cellular adaptations of mothers based on protein source diets during pregnancy and lactation, and leptin concentration in offspring. We evaluated metabolic parameters and maternal key organs and milk components in mothers at the end of lactation, who were fed different sources of proteins. In postnatal day 110 and 250, we studied development parameters and leptin in male offspring. Female rats received a Vegetal (V) or Animal (A) diet during pregnancy and lactation. After weaning, male offspring ate V diet until postnatal day 250, which yielded two groups: Vv and Av. Milk dry, protein and fat were analyzed. Maternal metabolic parameters, leptin, and liver, adipose tissue and mammary gland histological analyses were studied. Body weight, food intake and leptin were analyzed in offspring at two ages. Adipose tissue weight and cells size and liver fat, mammary gland apoptosis, weight, milk protein and leptin were higher in A vs V. Maternal liver and milk dry were lower in A vs V. All offspring parameters were higher in Av vs Vv at postnatal day 110; however, at postnatal day 250, leptin was higher in Av vs Vv. Maternal serum and milk leptin had a positive correlation with offspring serum leptin at both ages. Consumption of animal protein-based diets by mothers during developmental periods affects specific maternal organs and changes milk composition during lactation, leading to a hyperleptinemic phenotype in male offsprings.

Maternal obesity accelerates rat offspring metabolic ageing in a sex-dependent manner.

KEY POINTS: Maternal obesity predisposes to metabolic dysfunction in male and female offspring Maternal high-fat diet consumption prior to and throughout pregnancy and lactation accelerates offspring metabolic ageing in a sex-dependent manner This study provides evidence for programming-ageing interactions ABSTRACT: Human epidemiological studies show that maternal obesity (MO) shortens offspring life and health span. Life course cellular mechanisms involved in this developmental programming-ageing interaction are poorly understood. In a well-established rat MO model, female Wistar rats ate chow (controls (C)) or high energy, obesogenic diet to induce MO from weaning through pregnancy and lactation. Females were bred at postnatal day (PND) 120. Offspring (F1 ) of mothers on control diet (CF1 ) and MO diet (MOF1 ) delivered spontaneously at terms. Both CF1 and MOF1 ate C diet from weaning throughout the study. Offspring were killed at PND 36, 110, 450 and 650. We determined body and liver weights, liver and serum metabolite concentrations, hormones and oxidative stress biomarkers. Male and female CF1 body weight, total fat, adiposity index, serum leptin, insulin, insulin resistance, and liver weight, fat, triglycerides, malondialdehyde, reactive oxygen species and nitrotyrosine all rose with differing ageing trajectories. Female CF1 triglycerides were unchanged with age. Age-related increases were greater in MOF1 than CF1 in both sexes for all variables except glucose in males and females and cholesterol in males. Cholesterol fell in CF1 females but not MOF1 . Serum corticosterone levels were higher in male and female MOF1 than CF1 and declined with age. DHEA serum levels were lower in male and female MOF1 than CF1 . Liver antioxidant enzymes decreased with age (CF1 and MOF1 ). CONCLUSIONS: exposure to the developmental challenge of MO accelerates progeny ageing metabolic and endocrine profiles in a sex specific manner, providing evidence for programming-ageing interactions.

Gastrointestinal infection with Mexican TcI Trypanosoma cruzi strains: different degrees of colonization and diverse immune responses.

Mexican Ninoa and Queretaro (Qro) TcI strains of Trypanosoma cruzi have shown different degrees of virulence, and the two strains produce heterogeneous immune responses in the hearts of infected mice. This work shows that the same strains can invade the intestine by an intraperitoneal route and establish an infection, mainly in the colon. The three segments of the small intestine (duodenum, jejunum and ileum) were infected to a lesser degree than the colon. Despite the fact that parasites were predominantly found in the colon, an obvious inflammatory reaction was observed in the submucosal layer along the entire intestinal tract, with the virulent Qro strain causing significantly more areas of higher immune infiltration. A clear recruitment of CD4⁺ and CD8⁺ T lymphocytes to the mesenteric ganglia was observed during infection with the virulent strain. Macrophages were also differentially distributed in the gastrointestinal tract. These later cells infiltrated fewer amastigote nests in the mice infected with the Qro strain than in the mice infected with the Ninoa strain. When IFN-γ, TNF-α, and IL-4 levels were measured, an increase in these cytokines was observed compared with the uninfected mice. The role of these inflammatory reactions in the pathogenesis of Chagas enteropathy is also discussed in this paper.