Journal of Nutrition最新文献

Background: It is unknown whether pigs can detect deficiencies in multiple amino acids (AA) and consequently change their feed choice.

Objectives: We investigated whether pigs compensate for a diet deficient in three AA (Thr, Trp, and Val) by selecting multiple diets and whether this compensation is affected by the supplemented AA concentration.

Methods: Pair-housed 5-wk-old pigs (n = 96) were exposed to one of four treatments: 1) AA-adequate: offered a low-protein (LP) diet adequate in AA for growth (LP⁺); 2) AA-deficient: offered LP diet deficient in Thr, Trp, and Val by 20% (LP^-); 3) Two-choice between LP⁺ and LP^-; and 4) Four-choice between LP^- and three diets supplemented with Thr, Trp, Val at +40% (n = 12 pens/treatment) from d0 to d21 (phase 1). From d21 to d28, AA concentration of supplemented diets increased to +60% (phase 2). Average daily feed intake (ADFI) and gain (ADG) were recorded.

Results: Dietary treatment did not affect ADFI and ADG in phase 1 (P > 0.05). In phase 2, ADFI and ADG were higher in AA-adequate and two-choice treatments than in AA-deficient treatment with four-choice in between (P < 0.05). In both phases, Thr, Trp, and Val intake was lower in AA-deficient treatment than in other treatments. For the two-choice treatment, consumption of LP^- was higher than LP⁺ in both phases (P < 0.05 and P < 0.001). Four-choice treatment consumed more LP^- and Trp-supplemented than Thr- and Val-supplemented diets in phase 1 (P < 0.001); in phase 2, consumption of the Trp-supplemented diet was the highest (P < 0.01).

Conclusions: Pigs can detect multiple AA deficiencies and compensate by consuming AA-supplemented diets. In a two-choice setting, pigs proportionally decrease consumption of a supplemented diet with increased dietary AA concentration. However, when given the choice between individual AA-supplemented diets, pigs proportionally decrease consumption of a highly concentrated Val diet and increase preference for a highly concentrated Trp diet.

Poultry, a vital economic animal, provide a high-quality protein source for human nutrition. Over the past decade, the poultry industry has witnessed substantial achievements in breeding, precision feeding, and welfare farming. However, there are still many challenges restricting the sustainable development of the poultry industry. First, overly focused breeding strategies on production performance have been shown to induce metabolic diseases in poultry. Second, a lack of robust methods for assessing the nutritional requirements poses a challenge to the practical implementation of precision feeding. Third, antibiotic alternatives and feed safety management remain pressing concerns within the poultry industry. Lastly, environmental pollution and inadequate welfare management in farming have a negative effect on poultry health. Despite numerous proposed strategies and innovative approaches, each faces its own set of strengths and limitations. In this review, we aim to provide a comprehensive understanding of the poultry industry over the past decade, by examining its achievements, challenges, and strategies, to guide its future direction.

Background: Doubly labeled water is gold standard for measuring total energy expenditure (TEE). Measurements using the method are sensitive to the isotope dilution space ratio (DSR). Accuracy and precision of the method might be improved if we could identify factors influencing DSR.

Objectives: We evaluated the potential associations of age, sex, ethnicity, anthropometry, body composition, turnover rates of the isotopes, and geographical elevation with DSR.

Methods: We used univariate regression analysis to explore the relationships between the continuous variables and analysis of variance to test the relationships between the categorical variables with DSR. Subsequently, we used general linear model (GLM) and 1-way analysis of variance to evaluate the simultaneous associations of age, sex, ethnicity, fat-free mass (FFM) and fat mass (FM) on DSR.

Results: From 5678 measurements complied from studies around the world with diverse ethnicity and living at various elevations, the mean DSR was 1.0364 ± 0.0141. No meaningful physiologic effect of any of the continuous and categorical variable on DSR was detected. General linear model analysis revealed no effect of FFM and FM (P > 0.33) on DSR, but DSR decreased with age (P < 0.001) among those aged 60 y and older regardless of sex. Among the Whites who were younger than 60 y, DSR was not related to FFM and FM (P = 0.73) but was affected by both age and sex (P < 0.001).

Conclusions: Previous estimates of age-related decline in TEE may have overestimated TEE at age 90 y. Validation studies on older participants are required to confirm this finding.

Background: The dietary requirement for α-linolenic acid (ALA) remains unclear, as evidenced by the absence of a Recommended Dietary Allowance (RDA) for this essential fatty acid (FA). In previous studies, we observed that the amount of dietary ALA required to maximize nonesterified (NE) DHA oxylipins appears to be higher than the amount required to maximize tissue esterified DHA, which have classically been used to estimate the ALA requirement. Further, we observed that dietary ALA reduces esterified arachidonic acid (ARA) and its NE oxylipins.

Objectives: Since NE oxylipins and FA mediate the biological activities of FA, we examined whether these DHA and ARA pools could be used to determine the dietary ALA requirement.

Methods: Nine groups of 4-wk-old male Sprague-Dawley rats (n = 5) and 10 groups of male and female CD1 mice (n = 6) were provided 0.1-2.5 g ALA and 2 g of linoleic acid per 100 g of AIN93G-based diets. NE DHA and ARA and their oxylipins in serum, liver, kidney, and brain homogenates underwent solid phase extraction and were quantified by HPLC-MS/MS. Breakpoint analysis of transitions from increase to plateau was conducted using piecewise regression.

Results: In response to increasing dietary ALA, NE DHA oxylipins, and DHA in serum, liver, and kidney (but not the brain) initially increased rapidly and then reached a plateau whereas ARA oxylipins and ARA tended to decrease before reaching a plateau. Thus, breakpoints were calculated for the ratios of DHA/ARA and hydroxy-DHA/hydroxy-ARA (DHA_OH/ARA_OH), which consisted of oxylipins synthesized via pathways common to both FA. In serum, liver, and kidney, the highest estimated breakpoint indicated an ALA requirement of ∼0.7 g/100 g diet (1.7% energy), approximately twice that of previous estimations.

Conclusions: This study supports the use of NE DHA_OH/ARA_OH or DHA/ARA as biochemical indicators of the ALA requirement. Applying this method in rats and mice indicates that the requirement is higher than previously estimated using esterified DHA alone.

Background: Suckling and weaning arachidonic acid (ARA) + docosahexaenoic acid (DHA) supplementation promoted oral tolerance (OT) development in pups, however, the effect of it on the intestine to promote OT development remains unknown.

Objective: We aimed to explore the impact of this supplementation on intestinal fatty acid composition, structure, and indicators that are supportive of OT development.

Methods: Allergy-prone Brown Norway dams were randomly assigned to a control (0% ARA, 0% DHA) or ARA + DHA diet (0.45% ARA, 0.8% DHA) during suckling (0-3 wk). At weaning (3-8 wk), offspring were randomly assigned to a control (0% ARA, 0% DHA) or ARA + DHA diet (0.5% ARA, 0.5% DHA). At 3 wk, offspring in each group received an oral gavage of sucrose or ovalbumin (OVA) solution for five consecutive days. At 7 wk, all offspring received an intraperitoneal OVA injection. At 8 wk, offspring were terminated to evaluate jejunum morphology and measure mucosal food allergy-related secretory immunoglobulin A (sIgA) and cytokines, ileum phospholipid and triglyceride fatty acid compositions, and fecal calprotectin.

Results: Weaning ARA + DHA resulted in a higher percentage of DHA in ileum phospholipids and triglycerides (both P < 0.001), without affecting the percentage of ARA. Despite no lasting effect of suckling ARA + DHA on the DHA content in ileum phospholipids, a programming effect was found on the allergy-related intestinal immune profile [higher concentrations of mucosal IL-2 (P = 0.049) and sIgA (P = 0.033)]. OVA treatment resulted in a lower concentration of mucosal IL-6 (P = 0.026) regardless of dietary interventions. Offspring fed ARA + DHA during suckling and/or weaning had a higher concentration of mucosal transforming growth factor-beta (TGF-β) after OVA treatment but this was not observed in offspring fed control diets during suckling and weaning (P = 0.04).

Conclusions: Early life dietary ARA + DHA supplementation to allergy-prone rats enhanced the DHA concentration in intestinal phospholipids (weaning period) and increased the mucosal sIgA, IL-2, and TGF-β levels (suckling and weaning period), indicating its ability to create a tolerogenic intestinal environment to support OT development.

Background: Vitamin D is a hormone that regulates gene transcription. Prenatal vitamin D has been linked to immune and vascular function in the placenta, a key organ of pregnancy. Transcriptome-wide RNA sequencing can provide a more complete representation of the placental effects of vitamin D.

Objectives: We investigated the association between prenatal vitamin D concentrations and placental gene expression in a large, prospective pregnancy cohort.

Methods: Participants were recruited from Shelby County, TN, United States, in the Conditions Affecting Neurocognitive Development and Learning in Early childhood (CANDLE) study. Vitamin D (plasma total 25-hydroxyvitatmin D, [25(OH)D]) was measured at midpregnancy (16-28 wk) and delivery. RNA was sequenced from placental samples collected at birth. We identified differentially expressed genes (DEGs) using adjusted linear regression models. We also conducted weighted gene coexpression network analysis.

Results: The median 25(OH)D of participants was 21.8 ng/mL at midpregnancy (N = 774; IQR: 15.4-26.5 ng/mL) and 23.6 ng/mL at delivery (n = 753; IQR: 16.8-29.1 ng/mL). Placental expression of 17 DEGs was associated with 25(OH)D at midpregnancy, but only 1 DEG was associated with 25(OH)D at delivery. DEGs were related to energy metabolism, cytoskeletal function, and transcriptional regulation. We identified 2 weighted gene coexpression network analysis gene modules whose expression was associated with 25(OH)D at midpregnancy and 1 module associated with 25(OH)D at delivery. These modules were enriched for genes related to mitochondrial and cytoskeletal function and were regulated by transcription factors including ARNT2 and FOSL2. We also identified 12 modules associated with 25(OH)D in females and 1 module in males.

Conclusions: 25(OH)D during midpregnancy, but not at delivery, is associated with placental gene expression at birth. Future research is needed to investigate a potential role of vitamin D in modulating placental mitochondrial metabolism, intracellular transport, and transcriptional regulation during pregnancy.

Background: The risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via human milk-feeding is virtually nonexistent. Adverse effects of coronavirus disease 2019 (COVID-19) vaccination for lactating individuals are not different from the general population, and no evidence has been found that their infants exhibit adverse effects. Yet, there remains substantial hesitation among this population globally regarding the safety of these vaccines.

Objectives: Herein, we aimed to determine if compositional changes in milk occur following SARS-CoV-2 infection or COVID-19 vaccination, including any evidence of vaccine components.

Methods: An extensive multiomics approach was taken using a subset of milk samples obtained as part of our broad studies examining the effects on milk of SARS-CoV-2 infection and COVID-19 vaccination.

Results: We found that compared with unvaccinated individuals, SARS-CoV-2 infection was associated with significant compositional differences in 67 proteins, 385 lipids, and 13 metabolites. In contrast, COVID-19 vaccination was not associated with any changes in lipids or metabolites, although it was associated with changes in 13 or fewer proteins. Compositional changes in milk differed by vaccine. Changes following vaccination were greatest after 1-6 h for the mRNA-based Moderna vaccine (8 changed proteins), 3 d for the mRNA-based Pfizer (4 changed proteins), and adenovirus-based Johnson and Johnson (13 changed proteins) vaccines. Proteins that changed after both natural infection and Johnson and Johnson vaccine were associated mainly with systemic inflammatory responses. In addition, no vaccine components were detected in any milk sample.

Conclusions: Together, our data provide evidence of only minimal changes in milk composition because of COVID-19 vaccination, with much greater changes after natural SARS-CoV-2 infection.

Background: Dietary protein quality can be assessed by skeletal muscle protein synthesis (MPS) stimulation. Limited knowledge exists on how consuming isonitrogenous meals with varied protein qualities affects postprandial and 24-h MPS.

Objectives: We assessed the effects of protein quality and complementary proteins on MPS. We hypothesized that meals containing a moderate amount of high-quality, complete protein would stimulate postprandial and 24-h MPS. Meals containing two complementary, plant-based incomplete proteins would stimulate MPS less, and meals containing plant-based incomplete proteins at each meal, but complementary over 24 h would not stimulate MPS.

Methods: This quasi-experimental study included a randomized, crossover design to assess protein quality and a nonrandomized low-protein control. We measured postprandial and 24-h MPS responses of healthy middle-aged women (n = 9, age 56 ± 4 y), to 3 dietary conditions: isonitrogenous meals containing 23 g protein/meal from 1) complete protein (lean beef), 2) 2 incomplete, but complementary protein sources (navy/black beans and whole wheat bread), and 3) single incomplete protein sources (black beans or whole wheat bread at 1 meal), but providing a complete amino acid profile over 24 h. In the low-protein group women (n = 8, 54 ± 5 y) consumed a single breakfast meal containing 5 g of protein. Venous blood and vastus lateralis samples were obtained during primed, constant infusions of L-[ring-¹³C₆]phenylalanine to measure mixed muscle fractional synthetic rates (FSR).

Results: Meals containing complete, complementary, or incomplete proteins did not differentially influence FSR responses after breakfast (P = 0.90) or 24 h (P = 0.38). At breakfast, the complete (P = 0.030) and complementary (P = 0.031) protein meals, but not the incomplete protein meal (P = 0.38), had greater FSR responses compared with the low-protein control meal.

Conclusions: Isonitrogenous meals containing a moderate serving of total protein from foods providing complete, complementary, or incomplete essential amino acid profiles do not differentially stimulate muscle protein synthesis after a meal and daily.

Trial registration number: This clinical trial was registered at clinicaltrials.gov as NCT03816579. URL: https://www.

Clinicaltrials: gov/ct2/show/NCT03816579?term=NCT03816579&draw=2&rank=1.

Background: Eating in the absence of hunger (EAH) is a behavioral phenotype of pediatric obesity characterized by the consumption of palatable foods beyond hunger. Studies in children have identified EAH to be stable over time, but findings are unclear on whether it predicts the development of adiposity, particularly in middle childhood, a period of increased autonomy over food choices.

Objectives: We hypothesized that EAH would remain stable and be associated with increased adiposity over a ≥1-y prospective study in 7-8-y old children without obesity. Secondary hypotheses tested whether physical activity moderated the impact of EAH on adiposity.

Methods: Children (n =72, age 7.8 ± 0.6 y; BMI% <90th), in a 7-visit longitudinal study, had EAH, adiposity, and physical activity assessed at baseline (time 1 - T1) and follow-up (time 2 - T2). EAH was determined by measuring children's intake from 9 energy-dense (>3.9 kcal/g) sweet and savory foods during a 10-min access period after intake of a standard meal eaten to satiation. Adiposity was measured by dual-energy X-ray absorptiometry (DXA), with an outcome of fat mass index (FMI; fat mass/height in m²). Seven days of wrist-worn Actigraphy quantified moderate-to-vigorous-physical activity (MVPA) and sedentary time.

Results: EAH had moderate stability across time points (ICC = 0.54). ICCs were stronger for sweet (ICC = 0.53) than savory (ICC = 0.38) foods. Linear regression predicting 1-y change in FMI (adjusted for income, parent education, sex, time to follow-up, T2 Tanner stage, maternal weight status, and baseline adiposity) found that both total and sweet food EAH at baseline predicted increases in adiposity (P < 0.05 for both). EAH and adiposity were negatively correlated among children with high MVPA and low sedentary time.

Conclusions: These findings show that EAH is a stable predictive phenotype of increases in adiposity over 1 y among youth in middle childhood, although activity-related behaviors may moderate this effect. If replicated, targeting EAH as part of interventions may prevent excess adiposity gain.

Trial registration number: The data was obtained from the Food and Brain study with registration number: NCT03341247.