Weanling rats exposed to maternal low-protein diets during discrete periods of gestation exhibit differing severity of hypertension.
ABSTRACT 1. In the rat, hypertension is induced by fetal exposure to maternal low-protein diets. The effect on blood pressure of undernutrition before conception and during discrete periods in early, mid or late pregnancy was assessed using an 18% casein (control) diet and a 9% casein to apply mild protein restriction. 2. The offspring of rats fed 9% casein developed raised blood pressure by weaning age. Feeding a low-protein diet before conception was not a prerequisite for programming of hypertension. 3. Hypertension was observed in rats exposed to low protein during the following gestational periods: days 0-7, days 8-14 and days 15-22. Blood pressure increases elicited by these discrete periods of undernutrition were lower than those induced by feeding a low-protein diet throughout pregnancy. The effect in early gestation was significant only in male animals. Post-natal growth of male rats exposed to low-protein diets was accelerated, but kidneys were small in relation to body weight. 4. Biochemical indices of glucocorticoid action in liver, hippocampus, hypothalamus and lung were elevated in rats exposed to low-protein diets in utero. The apparent hypersensitivity to glucocorticoids was primarily associated with undernutrition in mid to late gestation. 5. Plasma renin activity was elevated in rats exposed to 9% casein over days 15-55 of gestation. Animals undernourished over days 0-7 and 8-14 produced pups with lower plasma angiotensin II concentrations at weaning. 6. Fetal exposure to maternal low-protein diets for any period in gestation may programme hypertension in the rat. Alterations to renal structure, renal hormone action or the hypothalamic-pituitary-adrenal axis may all play a role in the programming phenomenon, either independently or in concert.
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ABSTRACT: Studies assessing maternal dietary intakes and the relationship with birthweight are inconsistent, thus attempting to draw inferences on the role of maternal nutrition in determining the fetal growth trajectory is difficult. The aim of this review is to provide updated evidence from epidemiological and randomized controlled trials on the impact of dietary and supplemental intakes of omega-3 long-chain polyunsaturated fatty acids, zinc, folate, iron, calcium, and vitamin D, as well as dietary patterns, on infant birthweight. A comprehensive review of the literature was undertaken via the electronic databases Pubmed, Cochrane Library, and Medline. Included articles were those published in English, in scholarly journals, and which provided information about diet and nutrition during pregnancy and infant birthweight. There is insufficient evidence for omega-3 fatty acid supplements' ability to reduce risk of low birthweight (LBW), and more robust evidence from studies supplementing with zinc, calcium, and/or vitamin D needs to be established. Iron supplementation appears to increase birthweight, particularly when there are increases in maternal hemoglobin concentrations in the third trimester. There is limited evidence supporting the use of folic acid supplements to reduce the risk for LBW; however, supplementation may increase birthweight by ~130 g. Consumption of whole foods such as fruit, vegetables, low-fat dairy, and lean meats throughout pregnancy appears beneficial for appropriate birthweight. Intervention studies with an understanding of optimal dietary patterns may provide promising results for both maternal and perinatal health. Outcomes from these studies will help determine what sort of dietary advice could be promoted to women during pregnancy in order to promote the best health for themselves and their baby.Nutrients 01/2014; 7(1):153-178. DOI:10.3390/nu7010153 · 3.15 Impact Factor
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ABSTRACT: The aims of this study were to investigate the effects of a high-protein maternal diet on the fetal immune system development, and subsequently on resistance to the abomasal blood sucking parasite Haemonchus contortus in lambs after weaning. Merino ewes (n=39) of mixed age and parity were fed either a normal protein diet (12% CP) or a high-protein diet (21% CP) for the first 100 day of their 150 day gestation. The lambs were weaned at 3 months old and infected at 6 months of age with 10,000 L3 H. contortus larvae. No significant differences were found between the groups fed a normal protein diet and a high-protein diet in any of the variables measured in lambs (birth weight, fleece weight or fecal parasite egg counts) However, there were differences in hematological variables, except lymphocytes and monocytes, between lambs born to ewes fed 12% or 21% protein during the first 100 day of gestation. Fetal exposure to a maternal high-protein diet during the first 100 day of gestation did not appear to influence lamb susceptibility to experimental H. contortus infection in Merino lambs.Livestock Science 12/2012; 150(1-3):11-21. DOI:10.1016/j.livsci.2012.07.022 · 1.10 Impact Factor
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ABSTRACT: Lactoferrin (LF) content in infant milk powder has been strictly regulated by many governments and there is a need for convenient and reliable assays. Using hybridoma techniques, fourteen monoclonal antibodies (mAbs) active against LF were prepared. Two antibodies (mAb2 and mAb3), recognizing spatially distant epitopes of LF, were selected to establish a sandwich enzyme-linked immunosorbent assay (ELISA). A solution of mAb3 (1 μg mL−1) was coated onto micro-titer plates for LF capture while mAb2 labeled with horseradish peroxidase (2.2 μg mL−1) was used as a detection antibody. Under optimized conditions, the proposed sandwich ELISA was evaluated, and linearly responded to LF standards in a range of 5-600 ng mL−1 and the limit of detection was 3.23 ng mL−1. Lactoferrin samples were able to be determined after simple dilution, and the recovery in fortified milk powder averaged between 98% and 109%. The developed assay showed both high specificity (with no obvious cross-reactivity with related proteins) and reproducibility (the coefficient of variation ranged from 4.5% to 7.1%), indicating the utility of this sandwich ELISA in LF monitoring.Analytical methods 01/2014; 6(13):4742. DOI:10.1039/c4ay00321g · 1.94 Impact Factor