No abstract

Hydroxytyrosol is a polyphenol with antioxidant, metabolism-regulatory, anti-inflammatory and immuno-modulatory properties. The present study aimed to determine whether supplementing the maternal diet with hydroxytyrosol during pregnancy can improve pre- and early post-natal developmental patterns and metabolic traits of the offspring. Experiment was performed in Iberian sows fed a restricted diet in order to increase the risk of IUGR. Ten sows were treated daily with 1.5 mg of hydroxytyrosol per kg of feed between Day 35 of pregnancy (30% of total gestational period) until delivery whilst 10 animals were left untreated as controls. Number and weight of offspring were assessed at birth, on post-natal Day 15 and at weaning (25 days-old). At weaning, body composition and plasma indexes of glucose and lipids were measured. Treatment with hydroxytyrosol was associated with higher mean birth weight, lower incidence of piglets with low birth weight. Afterwards, during the lactation period, piglets in the treated group showed a higher body-weight than control piglets; such effects were even stronger in the most prolific litters. These results suggest that maternal supplementation with hydroxytyrosol may improve pre- and early post-natal development of offspring in pregnancies at risk of IUGR.

The use of polyphenols is a promising strategy for preventing or alleviating intrauterine growth restriction (IUGR) because polyphenol supplementation increases plasma antioxidant capacity and improves oxidative stress at the feto-placental unit; which are recognized as main issues in IUGR. However, there is a scarcity of experimental data on both realistic benefits and potential hazards of polyphenol supplementation during gestation. Hence, we aimed to use a swine model of IUGR pregnancy to determine possible effects of maternal supplementation with polyphenols (hydroxytyrosol) on placental expression of genes involved in antioxidant homeostasis, vascularization and fetal growth and thus on antioxidant status, DNA-methylation and phenotypic traits (morphology and homeostasis) of the fetus. Hydroxytyrosol improves placental gene expression and fetal antioxidant status and glucose metabolism in a sex-dependent manner, in which males were favored in spite of developmental failures. Concomitantly, hydroxytyrosol prevented hypomethylation of DNA associated with oxidative stress. Finally, no major deleterious effects of hydroxytyrosol supplementation on constriction of the ductus arteriosus, a possible secondary effect of polyphenols during pregnancy, were found.

Pregnancy and lactation are challenging states that affect maternal and lamb health. In Lacaune dairy sheep, we evaluated the impact of parity, pregnancy rank, and body condition on body weight and the condition of ewes and lambs in mid-pregnancy (75 ± 5 d), in late pregnancy (142 ± 4d), and postpartum (52 ± 5d pp). Maternal age was associated with initial decreases, followed by increases, in body weight and condition. After lambing, both mature and maiden ewes lost weight and body condition. Maternal indices of glucose, protein, and lipid metabolism were within physiological values during pregnancy, but postpartum values depended on maternal parity and pregnancy rank, with multiple-pregnant ewes showing a postpartum increase in glucose and maiden sheep a postpartum increase in plasma cholesterol concentration. Male lambs were heavier than female lambs at birth, and lambs born to mothers with higher body condition scores were heavier. Lambs born as singletons were heavier than those born in litters. Maternal age and pregnancy rank did not influence lamb metabolic indicators. Sex affected plasma concentrations of glucose, triglycerides, and cholesterol. Maternal metabolic indicators showed minimal effects on lamb phenotype. These results suggest that, when appropriately fed, dairy sheep can cover the metabolic demands of pregnancy and milk production, regardless of age and pregnancy rank.

Fetal or intrauterine growth restriction (FGR or IUGR) is a concerning health issue not only due to its implications in mortality and morbidity of neonates but also because of its long-term consequences on health and disease risk of the individuals. Its main cause is an insufficient supply of nutrients and oxygen by maternal (malnutrition or hypobaric hypoxia) or placental factors (placental insufficiency) during late gestation, when the requirements of fetus are higher. The availability of reliable animal models would be highly useful for the future development of diagnostic, preventive and therapeutic strategies. Most of the studies using animal models have been performed in rodents, while the use of large animals (sheep and swine) has been scarce. The objective of the current review is to offer an overview on the possibilities of using large animals for conducting translational research on IUGR related to inadequate maternal conditions and/or placental dysfunction.

BackgroundThe aim of this study was to determine how maternal undernutrition during pregnancy and offspring birth-weight can affect the postnatal development of offspring under farm conditions, which may lead to consequences in its meat and carcass quality. The current study involved a total of 80 litters from Iberian sows fed a diet fulfilling daily requirements (n = 47; control) or providing 70% daily requirements (n = 33; underfed) from d 38 to d 90 of gestation when fetal tissue development begins. After birth, piglets born live were classified as low birth-weight (LBW; < 1 kg) and normal birth-weight (NBW; ≥1 kg). During the growing phase, 240 control and 230 underfed pigs (50% males and females) distributed by BW category and sex were studied until the slaughter.ResultsAt birth and weaning, there were significant differences in all morphological measures and weight between NBW and LBW piglets as expected (P < 0.0005), but few effects of the gestational feed restriction. During the growing phase, NBW pigs continued with higher weight than LBW pigs on all the days of evaluation (P < 0.05), even though control-LBW-females and LBW-males showed a catch-up growth. However, underfed pigs showed slower growth and higher feed conversion ratio than control pigs (P < 0.0001) at 215 days old. Moreover, the average daily weight gain (ADWG) for the overall period was greater for NBW, male and control pigs than for their LBW, female and underfed pigs (P < 0.0001, P< 0.0005 and P< 0.05, respectively) and NBW pigs were slaughtered at a younger age than LBW pigs (P < 0.0001). After slaughtering, control pigs also had higher carcass yield and backfat depth than underfed pigs (P < 0.0005) and the maternal nutritional effect caused main changes in the polar lipid fraction of liver and loin. The fatty acid composition of loin in control pigs had higher C18:1n-9 and n-3 FA concentrations, as well as lower ∑n-6/∑n-3 ratio, than in underfed pigs (P < 0.005).ConclusionsIn brief, results showed that the effects of maternal nutritional restriction appeared and increased with offspring age, causing worse developmental patterns for underfed pigs than for control pigs.Electronic supplementary materialThe online version of this article (10.1186/s40104-018-0240-6) contains supplementary material, which is available to authorized users.

Maternal supplementation with hydroxytyrosol, a polyphenol present in olive leaves and fruits, is a highly promising strategy to improve the oxidative and metabolic status of fetuses at risk of intrauterine growth restriction, which may diminish the appearance of low-birth-weight neonates. The present study aimed to determine whether hydroxytyrosol, by preventing lipid peroxidation, may influence the fat accretion and energy homeostasis in the liver, as well as the fatty acid composition in the liver and muscle. The results indicate that hydroxytyrosol treatment significantly decreased the energy content of the fetal liver, without affecting fat accretion, and caused significant changes in the availability of fatty acids. There were significant increases in the amount of total polyunsaturated fatty acids, omega-3 and omega-6, which are highly important for adequate fetal tissue development. However, there were increases in the omega-6/omega-3 ratio and the desaturation index, which make further studies necessary to determine possible effects on the pro/anti-inflammatory status of the fetuses.

The present study aimed to determine whether developmental patterns, adiposity level and fatty-acid composition of fetuses exposed to maternal malnutrition are driven by their sex or their genotype, or both, as these may modulate the adaptive response to the intrauterine environment independently of the maternal genotype. We used a single maternal genotype (purebred Iberian (IB) sows), which was inseminated with heterospermic semen (obtained by mixing semen from Iberian and Large White (LW) boars), to obtain four different subsets of fetuses (male and female, purebred (IB×IB) and crossbred (IB×LW)) in Iberian purebred sows. Analysis of fetal phenotypes indicated a better adaptive response of the female offspring, which was modulated by their genotype. When faced with prenatal undernutrition, females prioritised the growth of vital organs (brain, liver, lungs, kidneys and intestine) at the expense of bone and muscle. Moreover, the analysis of fat composition showed a higher availability of essential fatty acids in the female sex than in their male counterparts and also in the Iberian genotype than in crossbred fetuses. These results are of high translational value for understanding ethnic differences in prenatal programming of postnatal health and disease status, and show evidence that prenatal development and metabolic traits are primarily determined by fetal sex and strongly modulated by fetal genotype.