Functional amino acids in growth, reproduction, and health

Importance of Selected Nutrients and Additives in the Feed of Pregnant Sows for the Survival of Newborn Piglets

This systematic review analyzed the effect of selected nutrients and additives in the feed of pregnant sows on the survival of newborn piglets. We analyzed 720 peer-reviewed publications in English in PubMed® and Web of Science®, dated July 2023 to January 2024, related to the effect of dietary supplementation with fatty acids and various percentages of protein, amino acids, and/or sources of dietary fiber on the offspring of gestating sows. While several papers evaluated the effect of nutrition on gestating sows, only a few delved into the distinct feeding strategies required at each stage of gestation to meet the NRC's nutritional requirements for maternal tissue gain and postnatal neonatal survival and growth. This body of research suggests that as gestation progresses the sow's nutritional requirements increase, as the NRC established, to satisfy their own metabolic needs and those of their fetuses. Additional research is needed to determine an optimal feeding strategy.

Accurate models and nutritional strategies for specific oxidative stress factors: Does the dose matter in swine production?

Oxidative stress has been associated with a number of physiological problems in swine, including reduced production efficiency. Recently, although there has been increased research into regulatory mechanisms and antioxidant strategies in relation to oxidative stress-induced pig production, it remains so far largely unsuccessful to develop accurate models and nutritional strategies for specific oxidative stress factors. Here, we discuss the dose and dose intensity of the causes of oxidative stress involving physiological, environmental and dietary factors, recent research models and the antioxidant strategies to provide theoretical guidance for future oxidative stress research in swine.

Thermo-reversible self-assembled novel gellan gum hydrogels containing amino acid biogelators with antibacterial activity

In recent years, hydrogels derived from natural polymers have gained considerable attention. However, lack of mechanical strength and poor stability has become major lacuna of such systems. Scientists have attempted to resolve this problem by introducing chemical cross-linkers or synthetic modifications of natural polymers. In contrast, biological cross-linkers may be more beneficial due to their cytocompatibility and non-immunogenicity. As a biogelator, amino acids (AA) may be lucrative, yet they remain untapped till date. Present study, for the first time, reports exploitation of ʟ-Lysine, ʟ-Arginine, ʟ-Aspartic acid, and ʟ-Glutamic acid as biogelator to fabricate novel gellan gum (GG) hydrogels through green chemistry. Furthermore, as a first instance, molecular docking was applied to gain insight into the interaction between GG and AA. As predicted through docking, physical cross-linking of these hydrogels accounted for their thermo-reversibility. Moreover, to assess the suitability of prepared hydrogel for its intended use, systematic characterization studies were performed via FTIR, Raman spectroscopy, XRD, FE-SEM, and TGA. Additionally, rheological behavior of hydrogels was investigated using variety of parameters. Interestingly, GG-AA hydrogels exhibited around 99 % antibacterial activity against multidrug-resistant bacteria. According to the findings of this study, these novel hydrogels may have immense potential in the food and biomedical sectors.

Effect of diet supplemented with functional amino acids and polyphenols on gut health in broilers subjected to a corticosterone-induced stress

To address the overuse of antimicrobials in poultry production, new functional feed ingredients, i.e. ingredients with benefits beyond meeting basic nutritional requirements, can play a crucial role thanks to their prophylactic effects. This study evaluated the effects of the supplementation of arginine, threonine and glutamine together with grape polyphenols on the gut integrity and functionality of broilers facing a stress condition. 108 straight-run newly hatched Ross PM3 chicks were kept until 35 days and were allocated to 3 treatments. Broilers in the control group were raised in standard conditions. In experimental groups, birds were administered with corticosterone in drinking water (CORT groups) to impair the global health of the animal and were fed a well-balanced diet supplemented or not with a mix of functional amino acids together with grape extracts (1 g/kg of diet-CORT + MIX group). Gut permeability was significantly increased by corticosterone in non-supplemented birds. This corticosterone-induced stress effect was alleviated in the CORT + MIX group. MIX supplementation attenuated the reduction of crypt depth induced by corticosterone. Mucin 2 and TNF-α gene expression was up-regulated in the CORT + MIX group compared to the CORT group. Caecal microbiota remained similar between the groups. These findings indicate that a balanced diet supplemented with functional AA and polyphenols can help to restore broiler intestinal barrier after a stress exposure.

Beyond protein synthesis: the emerging role of arginine in poultry nutrition and host-microbe interactions

Arginine is a functional amino acid essential for various physiological processes in poultry. The dietary essentiality of arginine in poultry stems from the absence of the enzyme carbamoyl phosphate synthase-I. The specific requirement for arginine in poultry varies based on several factors, such as age, dietary factors, and physiological status. Additionally, arginine absorption and utilization are also influenced by the presence of antagonists. However, dietary interventions can mitigate the effect of these factors affecting arginine utilization. In poultry, arginine is utilized by four enzymes, namely, inducible nitric oxide synthase arginase, arginine decarboxylase and arginine: glycine amidinotransferase (AGAT). The intermediates and products of arginine metabolism by these enzymes mediate the different physiological functions of arginine in poultry. The most studied function of arginine in humans, as well as poultry, is its role in immune response. Arginine exerts immunomodulatory functions primarily through the metabolites nitric oxide (NO), ornithine, citrulline, and polyamines, which take part in inflammation or the resolution of inflammation. These properties of arginine and arginine metabolites potentiate its use as a nutraceutical to prevent the incidence of enteric diseases in poultry. Furthermore, arginine is utilized by the poultry gut microbiota, the metabolites of which might have important implications for gut microbial composition, immune regulation, metabolism, and overall host health. This comprehensive review provides insights into the multifaceted roles of arginine and arginine metabolites in poultry nutrition and wellbeing, with particular emphasis on the potential of arginine in immune regulation and microbial homeostasis in poultry.

Biomolecular profiles of Arctic sea-ice diatoms highlight the role of under-ice light in cellular energy allocation

Arctic sea-ice diatoms fuel polar marine food webs as they emerge from winter darkness into spring. Through their photosynthetic activity they manufacture the nutrients and energy that underpin secondary production. Sea-ice diatom abundance and biomolecular composition vary in space and time. With climate change causing short-term extremes and long-term shifts in environmental conditions, understanding how and in what way diatoms adjust biomolecular stores with environmental perturbation is important to gain insight into future ecosystem energy production and nutrient transfer. Using synchrotron-based Fourier transform infrared microspectroscopy, we examined the biomolecular composition of five dominant sea-ice diatom taxa from landfast ice communities covering a range of under-ice light conditions during spring, in Svalbard, Norway. In all five taxa, we saw a doubling of lipid and fatty acid content when light transmitted to the ice-water interface was >5% but <15% (85%-95% attenuation through snow and ice). We determined a threshold around 15% light transmittance after which biomolecular synthesis plateaued, likely because of photoinhibitory effects, except for Navicula spp., which continued to accumulate lipids. Increasing under-ice light availability led to increased energy allocation towards carbohydrates, but this was secondary to lipid synthesis, whereas protein content remained stable. It is predicted that under-ice light availability will change in the Arctic, increasing because of sea-ice thinning and potentially decreasing with higher snowfall. Our findings show that the nutritional content of sea-ice diatoms is taxon-specific and linked to these changes, highlighting potential implications for future energy and nutrient supply for the polar marine food web.

An investigation on protein and amino acid contents in scales and muscles of pomfret Parastromateus niger (Bloch, 1795) and Pampus argenteus (Eupharasen, 1788)

Abstract The present investigation was aimed to examine the percentage quantity of protein and amino acids in scales and muscles of Pampus argenteus and Parastromateus niger gathered from the local fish market of district Quetta of Balochistan. About 80 specimens of these two species, i.e., Pampus argenteus (N=40) and Parastromateus niger (N = 40), were collected from April 2017 to May 2018. In general, crude protein content was high in scales, that is, 71.03% in Parastromateus niger and 52.11% in Pampus argenteus, as well as in muscles of two Pomfret species of fishes i.e., 63.44% in Pampus argenteus and 60.99% in Parastromateus niger on a dry-weight basis, respectively. Likewise, the muscles and scales of Parastromateus niger reveal well compositions of amino acids that include proline was found to be high, and methionine was less than other amino acids, whereas threonine was found high in the scales of Pampus argenteus, but methionine was observed in lesser amount. However, the amino acids found in Pampus argenteus muscles also showed different compositions, such as lysine was found to be high, but histidine was less, respectively. In comparison, amino acids like tryptophan and cysteine were not detected in both scales and muscles of thesePomfret species of fishes. Thus, this study was based on analyzing the utilization of both Pomfret species of scales and meat whether they could have values as good supplements of both protein and certain kinds of essential amino acids in animal diets.

Ethylene enhances transcriptions of asparagine biosynthetic genes in soybean (Glycine max L. Merr) leaves

Soybean, a vital protein-rich crop, offers bioactivity that can mitigate various chronic human diseases. Nonetheless, soybean breeding poses a challenge due to the negative correlation between enhanced protein levels and overall productivity. Our previous studies demonstrated that applying gaseous phytohormone, ethylene, to soybean leaves significantly boosts the accumulation of free amino acids, particularly asparagine (Asn). Current studies also revealed that ethylene application to soybeans significantly enhanced both essential and non-essential amino acid contents in leaves and stems. Asn plays a crucial role in ammonia detoxification and reducing fatigue. However, the molecular evidence supporting this phenomenon remains elusive. This study explores the molecular mechanisms behind enhanced Asn accumulation in ethylene-treated soybean leaves. Transcriptional analysis revealed that ethylene treatments to soybean leaves enhance the transcriptional levels of key genes involved in Asn biosynthesis, such as aspartate aminotransferase (AspAT) and Asn synthetase (ASN), which aligns with our previous observations of elevated Asn levels. These findings shed light on the role of ethylene in upregulating Asn biosynthetic genes, subsequently enhancing Asn concentrations. This molecular insight into amino acid metabolism regulation provides valuable knowledge for the metabolic farming of crops, especially in elevating nutraceutical ingredients with non-genetic modification (GM) approach for improved protein content.

Nonessential amino acids in tropical ruminant feed: Investigating grass and legume forages of Indonesia

Objective

This study aimed to examine the concentration of nonessential amino acids (NEAAs) in ruminant feed in tropical areas, with a focus on forage grasses and legumes in Indonesia.

Materials and Methods

A total of 11 grasses (Chrysopogon zizanioides, Brachiaria brizantha, Brachiaria humidicola, Paspalum dilatatum, Paspalum atatum, Chloris gayana, Pennisetum polystachion, Panicum maximum, Cenchrus biflorus, Andropogon canaliculatus, and Digotaria decumbens) and six legumes (Arachis hypogaea, Pueararia Javanica, Centrosema pubescens, Clitoria ternatea, and Arachis pintoi) were analyzed for NEAA content using high-performance liquid chromatography (HPLC).

Results

Based on the results of this research, it was found that almost all NEAA content in forage was less than 3% (Serine (Ser), Alanine (Ala), Glycine (Gly), Tyrosine (Tyr), Proline (Pro), Cysteine (Cys), and Asparagine (Asn), except for glutamic (Glu) acid and arginine (Arg) in some legumes. The Glu content in grass ranges from 0.76% to 2.61%, and the Arg content ranges from 0.92% to 2.09%. These two NEAAs were most abundant in grasses and legumes, with concentrations of 5.10% to 6.27% and 3.10% to 5.53%, respectively.

Conclusion

Our study concluded that Glu and Arg were the most abundant NEAAs in tropical forages in Indonesia, with legumes having a higher concentration of NEAAs compared to grasses. Among the legumes, A. hypogaea had the highest NEAA content (23.40%), while among the forages, C. zizanioides had the highest NEAA content (12.37%). However, it was observed that neither legumes nor grasses could fulfill the metabolizable TNEAAs requirements for gaining cattle (250 kg of empty body weight gain), unlike commercial concentrates, which were found to meet the requirements, especially for Arg, Glu, and thyronine. The provision of concentrate is necessary to supplement forage to meet the NEAA needs for cattle.

Effects of crude protein and non-essential amino acids on growth performance, blood profile, and intestinal health of weaned piglets

This study investigated the effect of crude protein (CP) and non-essential amino acid (NEAA) supplementation on the growth performance, blood profile, intestinal morphology, mRNA relative abundance of inflammatory and antioxidant markers, and tight junction proteins in piglets over the first 2 weeks after weaning. Ninety 21-day-old piglets (7.55 ± 0.72 kg) were assigned in a randomized block design to one of three dietary treatments: (1) high CP, a diet with 24% CP; (2) low CP, a diet with 18% CP; and (3) low CP + NEAA, a diet with 18% CP supplemented with 5 g/kg Arg (L-arginine; purity >99%) and 10 g/kg Glu + Gln (minimum 10% L-glutamine and minimum 10% L-glutamate). Piglets were fed with corn-soybean meal basal diets in a 14-day trial. There was an improvement (p < 0.05) in the feed conversion ratio of piglets fed the high-CP diet compared to treatments with low CP or low CP + NEAA. Serum urea nitrogen was higher (p < 0.05) in piglets fed high CP compared to other dietary treatments. In the duodenum, the villus height of animals fed the low-CP + NEAA diets was greater (p < 0.05) than those fed with the high- and low-CP diets. The goblet cell proportion of piglets fed low CP + NEAA or high CP was higher (p < 0.05) compared to low CP. In the jejunum, the crypt depth of the piglets with the high-CP dietary treatment was greater (p < 0.05) in comparison with low CP + NEAA. In the jejunum, IFN-γ mRNA expression was higher (p < 0.05) in animals fed the high-CP diets compared to other dietary treatments. However, superoxide dismutase and occludin mRNA expression were higher (p < 0.05) in animals fed low CP + NEAA than in piglets on the high-CP diets. In the ileum, the number of Peyer's patches in piglets fed high CP was higher (p < 0.05) compared to other dietary treatments. In conclusion, the high-CP diet (24% CP) improves the feed conversion of piglets in the first 2 weeks after weaning compared to the low-CP diet (18% CP) supplemented or not with NEAA. However, the low-CP diet supplemented with NEAA (Arg, Gln, and Glu) improves intestinal health in piglets by promoting greater villus height and proportion of goblet cells in the duodenum, reducing jejunal crypt depth, and reducing Peyer's number patches in the ileum. In addition, piglets that received the low-CP + NEAA diet showed an increase in superoxide dismutase and occludin and a lower expression of IFN-γ mRNA.

Studying the non-thermal effects of microwave on amino acids in sterilized rainbow trout (Oncorhynchus mykiss) fillets using a double side approximating method

The aim of this study was to investigate the impact of microwave non-thermal effects on thermal sensitive amino acids in rainbow trout (Oncorhynchus mykiss) fillets. To distinguish non-thermal effects from thermal effects occurring simultaneously, a Double Side Approximating Method (DSAM) derived from computational mathematics was developed. Two corresponding water bath treatments were designed for each microwave processing to approximate the time-temperature profiles at the hot and cold spots of the microwave processed samples while maintaining a comparable thermal intensity (F0). The microwave non-thermal effects on amino acids were determined by comparing the amount of each of 22 amino acids between the microwave processed and the two corresponding water bath treated rainbow trout fillets. The results indicated that the DSAM was successfully implemented, as the amino acid contents' order curve in the microwave processed samples was clearly exceeded the boundary formed by the two corresponding water bath treated samples. This finding confirmed the occurrence of microwave non-thermal effects on amino acids. The non-thermal effect resulted in a notable increase in the quantity of most amino acids, while it reduced the content of Lys and Hyp. Longer microwave processing times intensified these effects, while higher thermal processing intensities resulted in more damage to each amino acid.

Alfalfa leaf meal as a new protein feedstuff improves meat quality by modulating lipid metabolism and antioxidant capacity of finishing pigs

The effects of alfalfa leaf meal (ALM) on the meat quality of finishing pigs are largely unknown. Here, we investigated the effects of ALM diet on meat quality by replacing 0%, 25%, 50%, and 75% of soybean meal in the diet of finishing pigs, respectively. The findings showed that 25% ALM diet increased the IMF, cooked meat rate, a* and antioxidant capacity of longissimus dorsi (LD), improved amino acid composition, increased MUFA content, and increased LD lipid synthesis and mRNA expression of antioxidation-related genes. At the same time, ALM diet altered serum lipid metabolism (TG, FFA). Correlation analysis showed that antioxidant capacity was positively correlated with meat quality. In addition, metabolomic analysis of LD showed that the main metabolites of 25% ALM diet altered stachydrine and l-carnitine were associated with meat quality and antioxidant capacity. In conclusion, ALM replacing 25% soybean meal diet can improve the meat quality of pigs.

Nutrient Composition of Ovary, Hepatopancreas and Muscle Tissues in Relation to Ovarian Development Stage of Female Swimming Crab, Portunus trituberculatus

The swimming crab Portunus trituberculatus is one of the most important economic species in China and its mature ovary often determines its commercial value and production. Although the ovary maturation of crustaceans is generally affected by exogenous nutrition, the specific nutritional needs of ovary maturation of P. trituberculatus are poorly understood. To this end, we collected the P. trituberculatus samples with five ovarian maturation stages and measured their biochemical composition of the ovary, hepatopancreas, and muscle at each ovarian developmental stage. We further analyzed their relation to the ovarian developmental stage of P. trituberculatus by principal components analysis (PCA). We found the levels of branched-chain amino acids, long-chain polyunsaturated fatty acids (LC-PUFA), and monounsaturated fatty acids (MUFAs) in the ovary and hepatopancreas increased during the ovary maturation process, and also passively correlated with ovarian developmental stage, which highlights the necessity of these specific nutrients for oogenesis and for improving the nutrient quality of crabs. In addition, we found an increasing tendency of carotenoid content and phosphatidylcholine in phospholipid in the ovary from the pre-developmental stage to the proliferative stage, but not in the hepatopancreas and muscle, which highlights the possible involvement of carotenoids during the rapid oocyte development process. Our study may provide valuable information for developing a suitable broodstock diet that promotes the ovarian maturation of adult P. trituberculatus and ensures high-quality larval production.

L-methionine supplementation modulates IgM+ B cell responses in rainbow trout

The interest in dietary amino acids (AAs) as potential immunomodulators has been growing the recent years, since specific AAs are known to regulate key metabolic pathways of the immune response or increase the synthesis of some immune-related proteins. Methionine, tryptophan and lysine are among the ten essential AAs for fish, meaning that they cannot be produced endogenously and must be provided through the diet. To date, although dietary supplementation of fish with some of these AAs has been shown to have positive effects on some innate immune parameters and disease resistance, the effects that these AAs provoke on cells of the adaptive immune system remained unexplored. Hence, in the current study, we have investigated the effects of these three AAs on the functionality of rainbow trout (Oncorhynchus mykiss) IgM+ B cells. For this, splenic leukocytes were isolated from untreated adult rainbow trout and incubated in culture media additionally supplemented with different doses of methionine, tryptophan or lysine in the presence or absence of the model antigen TNP-LPS (2,4,6-trinitrophenyl hapten conjugated to lipopolysaccharide). The survival, IgM secreting capacity and proliferation of IgM+ B cells was then studied. In the case of methionine, the phagocytic capacity of IgM+ B cells was also determined. Our results demonstrate that methionine supplementation significantly increases the proliferative effects provoked by TNP-LPS and also up-regulates the number of cells secreting IgM, whereas tryptophan or lysine have either minor or even negative effects on rainbow trout IgM+ B cells. This increase in the number of IgM-secreting cells in response to methionine surplus was further verified in a feeding experiment, in which the beneficial effects of methionine on the specific response to anal immunization were also confirmed. The results presented demonstrate the beneficial effects of dietary supplementation with methionine on the adaptive immune responses of fish.

Metabolic impact of high lipid low dextrose parenteral nutrition

BACKGROUND

Parenteral nutrition (PN) containing 100% soybean oil lipids and high amounts of dextrose may lead to liver dysfunction and hyperglycemia. Mixed lipids have less pro-inflammatory components, so higher doses may be given to decrease the amount of dextrose provided. The purpose of this study is to provide a descriptive analysis of patients who received PN with high mixed lipid and low dextrose content versus PN with lower 100% soybean oil lipid and high dextrose content.

METHODS

We retrospectively reviewed 62 patients aged ≥18 years receiving PN ≥ 7 days from 2016 to 2021 in an acute care hospital. Participants were divided into two groups: high lipid low dextrose (HLLD) containing a four-oil lipid (>30% kcal or ≥1 g/kg) vs adequate lipid high dextrose (ALHD) containing a 100% soybean oil lipid (<30% kcal or <1 g/kg SO-ILE).

RESULTS

Patients in the HLLD group (n = 31) had 64.1% lower incidence of blood glucose levels >180 mg/dL, decreased insulin requirements, 52.7% lower alkaline phosphatase levels, 40.6% higher prealbumin levels, and 42.6% lower c-reactive protein levels while maintaining similar calorie targets compared to the ALHD group (n = 31).

CONCLUSION

Changing from 100% soybean oil to a mixed lipid in PN is helpful to reduce soybean oil intake. However, it is also important to increase the mixed lipid dose to decrease the amount of dextrose provided. PNs containing higher amounts of mixed lipids (40-45% kcal) with lower amounts of dextrose (20-30% kcal) may have clinical benefits that warrant further exploration.

Nitric Oxide as a Determinant of Human Longevity and Health Span

The master molecular regulators and mechanisms determining longevity and health span include nitric oxide (NO) and superoxide anion radicals (SOR). L-arginine, the NO synthase (NOS) substrate, can restore a healthy ratio between the dangerous SOR and the protective NO radical to promote healthy aging. Antioxidant supplementation orchestrates protection against oxidative stress and damage-L-arginine and antioxidants such as vitamin C increase NO production and bioavailability. Uncoupling of NO generation with the appearance of SOR can be induced by asymmetric dimethylarginine (ADMA). L-arginine can displace ADMA from the site of NO formation if sufficient amounts of the amino acid are available. Antioxidants such as ascorbic acids can scavenge SOR and increase the bioavailability of NO. The topics of this review are the complex interactions of antioxidant agents with L-arginine, which determine NO bioactivity and protection against age-related degeneration.

Assessment of Bio-Compounds Content, Antioxidant Activity, and Neuroprotective Effect of Red Cabbage (Brassica oleracea var. Capitata rubra) Processed by Convective Drying at Different Temperatures

Parkinson's disease (PD) is the second most common neurodegenerative disorder, and no efficient therapy able to cure or slow down PD is available. In this study, dehydrated red cabbage was evaluated as a novel source of bio-compounds with neuroprotective capacity. Convective drying was carried out at different temperatures. Total phenolics (TPC), flavonoids (TFC), anthocyanins (TAC), and glucosinolates (TGC) were determined using spectrophotometry, amino acid profile by LC-DAD and fatty acid profile by GC-FID. Phenolic characterization was determined by liquid chromatography-high-resolution mass spectrometry. Cytotoxicity and neuroprotection assays were evaluated in SH-SY5Y human cells, observing the effect on preformed fibrils of α-synuclein. Drying kinetic confirmed a shorter processing time with temperature increase. A high concentration of bio-compounds was observed, especially at 90 °C, with TPC = 1544.04 ± 11.4 mg GAE/100 g, TFC = 690.87 ± 4.0 mg QE/100 g and TGC = 5244.9 ± 260.2 µmol SngE/100 g. TAC degraded with temperature. Glutamic acid and arginine were predominant. Fatty acid profiles were relatively stable and were found to be mostly C18:3n3. The neochlorogenic acid was predominant. The extracts had no cytotoxicity and showed a neuroprotective effect at 24 h testing, which can extend in some cases to 48 h. The present findings underpin the use of red cabbage as a functional food ingredient.

Molecular mechanisms of physiological change under acute total dissolved gas supersaturation stress in yellow catfish (Pelteobagrus fulvidraco)

During the dam discharging period, the strong aeration of high-speed water leads to the supersaturation of total dissolved gas (TDG) in the downstream water, which causes gas bubble disease (GBD) in fish and threatens their survival. TDG supersaturation has now become an ecological and environmental issue of global concern; however, the molecular mechanism underlying the physiological effect of TDG supersaturation on fish is poorly known. Here, we comprehensively investigated the effect of TDG supersaturation on Pelteobagrus fulvidraco at the histopathological, biochemical, transcriptomic, and metabolomic levels. After exposure to 116% TDG, P. fulvidraco exhibited classic GBD symptoms and pathological changes in gills. The level of superoxide dismutase was highly significantly decreased. Transcriptomic results revealed that heat shock proteins (HSPs) and a large number of genes involved in immunity were increased by TDG stress. A key environmental sensor PI3K/Akt/mTOR pathway was significantly stimulated for defence against stress. Integrated transcriptomic and metabolomic analyses revealed that key metabolites and genes were upregulated in the triacylglycerol synthesis pathway and that amino acid levels decreased, which might be associated with TDG supersaturation stress. The present study demonstrated that TDG supersaturation could cause severe physiological damage in fish. HSP genes, immune functions, and energy metabolic pathways were enhanced to counteract the adverse effects.

Targeting the metabolic profile of amino acids to identify the key metabolic characteristics in cerebral palsy

Background

Cerebral palsy (CP) is a neurodevelopmental disorder characterized by motor impairment. In this study, we aimed to describe the characteristics of amino acids (AA) in the plasma of children with CP and identify AA that could play a potential role in the auxiliary diagnosis and treatment of CP.

Methods

Using high performance liquid chromatography, we performed metabolomics analysis of AA in plasma from 62 CP children and 60 healthy controls. Univariate and multivariate analyses were then applied to characterize different AA. AA markers associated with CP were then identified by machine learning based on the Lasso regression model for the validation of intra-sample interactions. Next, we calculated a discriminant formula and generated a receiver operating characteristic (ROC) curve based on the marker combination in the discriminant diagnostic model.

Results

A total of 33 AA were detected in the plasma of CP children and controls. Compared with controls, 5, 7, and 10 different AA were identified in total participants, premature infants, and full-term infants, respectively. Of these, β-amino-isobutyric acid [p = 2.9*10(-4), Fold change (FC) = 0.76, Variable importance of protection (VIP) = 1.75], tryptophan [p = 5.4*10(-4), FC = 0.87, VIP = 2.22], and asparagine [p = 3.6*10(-3), FC = 0.82, VIP = 1.64], were significantly lower in the three groups of CP patients than that in controls. The combination of β-amino-isobutyric acid, tryptophan, and taurine, provided high levels of diagnostic classification and risk prediction efficacy for preterm children with an area under the curve (AUC) value of 0.8741 [95% confidence interval (CI): 0.7322-1.000]. The discriminant diagnostic formula for preterm infant with CP based on the potential marker combination was defined by p = 1/(1 + e-(8.295-0.3848* BAIBA-0.1120*Trp + 0.0108*Tau)).

Conclusion

Full-spectrum analysis of amino acid metabolomics revealed a distinct profile in CP, including reductions in the levels of β-amino-isobutyric acid, tryptophan, and taurine. Our findings shed new light on the pathogenesis and diagnosis of premature infants with CP.

Glycine: The Smallest Anti-Inflammatory Micronutrient

Glycine is a non-essential amino acid with many functions and effects. Glycine can bind to specific receptors and transporters that are expressed in many types of cells throughout an organism to exert its effects. There have been many studies focused on the anti-inflammatory effects of glycine, including its abilities to decrease pro-inflammatory cytokines and the concentration of free fatty acids, to improve the insulin response, and to mediate other changes. However, the mechanism through which glycine acts is not clear. In this review, we emphasize that glycine exerts its anti-inflammatory effects throughout the modulation of the expression of nuclear factor kappa B (NF-κB) in many cells. Although glycine is a non-essential amino acid, we highlight how dietary glycine supplementation is important in avoiding the development of chronic inflammation.

Variation among arthropod taxa in the amino acid content of exoskeleton and digestible tissue

Arthropod consumption provides amino acids to invertebrates and vertebrates alike, but not all amino acids in arthropods may be digestible as some are bound in the exoskeleton. Consumers may not be able to digest exoskeleton in significant amounts or avoid it entirely (e.g., extraoral digestion). Hence, measures that do not separate digestible amino acids from those in exoskeleton may not accurately represent the amino acids available to consumers. Additionally, arthropods are taxonomically diverse, and it remains unclear if taxonomic differences also reflect differences in amino acid availability. Thus, we tested: (1) if there were consistent differences in the content and balance of amino acids between the digestible tissue and exoskeleton of arthropods and (2) if arthropod Orders differ in amino acid content and balance. We measured the amino acid content (mg/100 mg dry mass) and balance (mg/100 mg protein) of whole bodies and exoskeleton of a variety of arthropods using acid hydrolysis. Overall, there was higher amino acid content in digestible tissue. There were also significant differences in the amino acid balance of proteins in digestible tissue and exoskeleton. Amino acid content and balance also varied among Orders; digestible tissues of Hemiptera contained more of some essential amino acids than other Orders. These results demonstrate that arthropod taxa vary in amino acid content, which could have implications for prey choice by insectivores. In addition, exoskeleton and digestible tissue content differ in arthropods, which means that whole body amino acid content of an arthropod is not necessarily a predictor of amino acid intake of a predator that feeds on that arthropod.

Synthesis of glycine from 4-hydroxyproline in tissues of neonatal pigs

Glycine from sow's milk only meets 20% of the requirement of suckling piglets. However, how glycine is synthesized endogenously in neonates is not known. This study determined glycine synthesis from 4-hydroxyproline (an abundant amino acid in milk and neonatal blood) in tissues of sow-reared piglets with normal birth weights. Piglets were euthanized at 0, 7, 14 and 21 days of age, and their tissues were used to determine glycine synthesis from 0 to 5 mM 4-hydroxyproline, activities and mRNA expression of key glycine-synthetic enzymes, and their cell-specific localization. Activities of 4-hydroxyproline oxidase (OH-POX), proline oxidase (POX), serine hydroxymethyltransferase (SHMT), threonine dehydrogenase (TDH), alanine:glyoxylate transaminase (AGT), and 4-hydroxy-2-oxoglutarate aldolase (HOA) occurred in the kidneys and liver from all age groups of piglets, and in the pancreas of 7- to 21-day-old piglets. Activities of OH-POX and HOA were absent from the small intestine of newborn pigs but present in the small intestine of 7- to 21-day-old piglets and in the skeletal muscle of 14- to 21-day-old piglets. Between days 0 and 21 of age, the enzymatic activities of OH-POX, AGT, and HOA decreased in the liver and kidneys but increased in the pancreas and small intestine with age. The mRNA levels of these three enzymes changed in a manner similar to their enzymatic activities. In contrast to OH-POX, AGT, and HOA, the enzymatic activities of POX, SHMT, and TDH were present in the kidneys, liver, and intestine of all age groups of piglets. Glycine was synthesized from 0.1 to 5 mM 4-hydroxyproline in the liver and kidney from 0- to 21-day-old piglets, as well as the pancreas, small intestine, and skeletal muscle from 14- to 21-day-old piglets in a concentration-dependent manner. Collectively, our findings indicate that 4-hydroxyproline is used for the synthesis of glycine in tissues of piglets to compensate for the deficiency of glycine in milk.

Uncovering the Molecular Mechanisms of Cosolvency and Predicting the Cosolvency Phenomenon by Molecular Simulations: A Case Study of Amino Acids

Cosolvency is an intriguing thermodynamic phenomenon. However, the lack of theoretical research restricts its development and its further applications. In this work, l-alanine, l-phenylalanine, and L-tryptophan were selected as model substances to investigate the mechanism of cosolvency at the molecular level. First, the dissolution behaviors of three amino acids were characterized to determine the solvent ratios at the occurrence of the cosolvency phenomenon. Furthermore, amino acid molecules undergo a shift in molecular conformation, which leads to changes in inter/intramolecular interactions. A molecular dynamics simulation method was proposed to calculate the trends of inter/intramolecular interactions, demonstrating that the maximum point of the inter/intramolecular interaction ratio exactly corresponds to the occurrence of the cosolvency. The cosolvency phenomenon of l-proline and l-threonine was predicted successfully based on this simulation method. These results are likely to provide in-depth comprehension and guidance for predicting the cosolvency phenomenon of amino-acid-like substances.

Unlocking the Potential of Arginine Deprivation Therapy: Recent Breakthroughs and Promising Future for Cancer Treatment

Arginine is a semi-essential amino acid that supports protein synthesis to maintain cellular functions. Recent studies suggest that arginine also promotes wound healing, cell division, ammonia metabolism, immune system regulation, and hormone biosynthesis-all of which are critical for tumor growth. These discoveries, coupled with the understanding of cancer cell metabolic reprogramming, have led to renewed interest in arginine deprivation as a new anticancer therapy. Several arginine deprivation strategies have been developed and entered clinical trials. The main principle behind these therapies is that arginine auxotrophic tumors rely on external arginine sources for growth because they carry reduced key arginine-synthesizing enzymes such as argininosuccinate synthase 1 (ASS1) in the intracellular arginine cycle. To obtain anticancer effects, modified arginine-degrading enzymes, such as PEGylated recombinant human arginase 1 (rhArg1-PEG) and arginine deiminase (ADI-PEG 20), have been developed and shown to be safe and effective in clinical trials. They have been tried as a monotherapy or in combination with other existing therapies. This review discusses recent advances in arginine deprivation therapy, including the molecular basis of extracellular arginine degradation leading to tumor cell death, and how this approach could be a valuable addition to the current anticancer arsenal.

Evaluation of the Quality of Codonopsis Radix in Different Growth Years by the AHP-CRITIC Method

The quality of traditional Chinese medicines (TCM) has a significant correlation with the source and growth years. However, there is no research on the relationship between the growth period and the quality of Codonopsis Radix (CR). This work aims to evaluate the quality of CR in different growth years (2-5 years). First, the content of 6 efficacy-related and 28 nutrient-related components in different growth years of CR was analyzed. The results showed that with the increase in growth years of CR, the content of some components increased, while some decreased. Then, the AHP-CRITIC method was performed to score the CR in different growth years, the results showed that the comprehensive score of CR increased with the increase of growth years, and the 5-year-CR had the highest score. Finally, in vitro activity assays were designed to verify the evaluation results. The results demonstrated that with the increase of growth years, the spleen lymphocyte proliferation activity and DPPH free radical scavenging activity of CR were enhanced, which proved that the AHP-CRITIC method is reasonable to evaluate the quality of CR in different growth years. The aforementioned findings demonstrated that CR quality improved with longer planting years.

Glutamine boosts intestinal stem cell-mediated small intestinal epithelial development during early weaning: Involvement of WNT signaling

Early weaning usually causes small intestine epithelial development abnormality, increasing the risk of gastrointestinal diseases. Glutamine (Gln), enriching in plasma and milk, is widely reported to benefit intestinal health. However, whether Gln affects intestinal stem cell (ISC) activity in response to early weaning is unclear. Here, both the early weaning mice and intestinal organoids were used to study the role of Gln in regulating ISC activities. Results showed that Gln ameliorated early weaning-induced epithelial atrophy and augmented the ISC-mediated epithelial regeneration. Gln deprivation disabled ISC-mediated epithelial regeneration and crypt fission in vitro. Mechanistically, Gln augmented WNT signaling in a dose-dependent manner to regulate ISC activity, while WNT signaling blockage abolished the effects of Gln on ISCs. Together, Gln accelerates stem cell-mediated intestinal epithelial development associated with the augmentation of WNT signaling, which provides novel insights into the mechanism by which Gln promotes intestinal health.

Identification of Novel Biomarkers in Late Preterm Neonates with Respiratory Distress Syndrome (RDS) Using Urinary Metabolomic Analysis

Urine metabolomics is gaining traction as a means of identifying metabolic signatures associated with health and disease states. Thirty-one (31) late preterm (LP) neonates admitted to the neonatal intensive care unit (NICU) and 23 age-matched healthy LPs admitted to the maternity ward of a tertiary hospital were included in the study. Proton nuclear magnetic resonance (¹H NMR) spectroscopy was employed for urine metabolomic analysis on the 1st and 3rd days of life of the neonates. The data were analyzed using univariate and multivariate statistical analysis. A unique metabolic pattern of enhanced metabolites was identified in the NICU-admitted LPs from the 1st day of life. Metabolic profiles were distinct in LPs presenting with respiratory distress syndrome (RDS). The discrepancies likely reflect differences in the gut microbiota, either due to variations in nutrient intake or as a result of medical interventions, such as the administration of antibiotics and other medications. Altered metabolites could potentially serve as biomarkers for identifying critically ill LP neonates or those at high risk for adverse outcomes later in life, including metabolic risks. The discovery of novel biomarkers may uncover potential targets for drug discovery and optimal periods for effective intervention, offering a personalized approach.

Impacts of microgravity on amino acid metabolism during spaceflight

Spaceflight exerts an extreme and unique influence on human physiology as astronauts are subjected to long-term or short-term exposure to microgravity. During spaceflight, a multitude of physiological changes, including the loss of skeletal muscle mass, bone resorption, oxidative stress, and impaired blood flow, occur, which can affect astronaut health and the likelihood of mission success. In vivo and in vitro metabolite studies suggest that amino acids are among the most affected nutrients and metabolites by microgravity (a weightless condition due to very weak gravitational forces). Moreover, exposure to microgravity alters gut microbial composition, immune function, musculoskeletal health, and consequently amino acid metabolism. Appropriate knowledge of daily protein consumption, with a focus on specific functional amino acids, may offer insight into potential combative and/or therapeutic effects of amino acid consumption in astronauts and space travelers. This will further aid in the successful development of long-term manned space mission and permanent space habitats.

Peculiarities in the Amino Acid Composition of Sow Colostrum and Milk, and Their Potential Relevance to Piglet Development

The composition of mother's milk is considered the ideal diet for neonates. This study investigated how conserved or variable the amino acid profile of sow colostrum and milk is throughout lactation, compared with other studies in sows and other species. Twenty-five sows (parity one to seven) from one farm with gestation lengths of 114 to 116 d were sampled on d 0, 3, and 10 after parturition. The total amino acid profile of the samples was analyzed through ion-exchange chromatography, and the results were displayed as the percentage of total amino acid and compared with literature data. Most of the amino acid concentrations in sow milk decreased significantly (p < 0.05) throughout the lactation period, while the amino acid profile generally showed a conserved pattern, especially from d 3 to d 10, and was rather similar across different studies. Glutamine + glutamate was the most abundant amino acid in milk at all sampling moments, accounting for 14-17% of total amino acids. The proportions of proline, valine, and glycine in sow milk nearly accounted for 11%, 7%, and 6% respectively, and were higher compared to human, cow, and goat milk, while the methionine proportion was less than the other three. Compared to the large variations often reported in macronutrient concentrations, the amino acid profile of sow milk in the present study, as well as in others, seems well conserved across the lactation period. Similarities with characteristic differences were also observed between sow milk and piglet body composition, which might reflect the nutrition requirements of preweaning piglets. This study warrants further research exploring the link between the whole amino acid profile and the particular amino acids for suckling piglets and could facilitate insight for optimizing creep feed.

Feeding broiler chickens with arginine above recommended levels: effects on growth performance, metabolism, and intestinal microbiota

BACKGROUND

Arginine is an essential amino acid for chickens and feeding diets with arginine beyond the recommended levels has been shown to influence the growth performance of broiler chickens in a positive way. Nonetheless, further research is required to understand how arginine supplementation above the widely adopted dosages affects metabolism and intestinal health of broilers. Therefore, this study was designed to assess the effects of arginine supplementation (i.e., total arginine to total lysine ratio of 1.20 instead of 1.06-1.08 recommended by the breeding company) on growth performance of broiler chickens and to explore its impacts on the hepatic and blood metabolic profiles, as well as on the intestinal microbiota. For this purpose, 630 one-day-old male Ross 308 broiler chicks were assigned to 2 treatments (7 replicates each) fed a control diet or a crystalline L-arginine-supplemented diet for 49 d.

RESULTS

Compared to control birds, those supplemented with arginine performed significantly better exhibiting greater final body weight at D49 (3778 vs. 3937 g; P < 0.001), higher growth rate (76.15 vs. 79.46 g of body weight gained daily; P < 0.001), and lower cumulative feed conversion ratio (1.808 vs. 1.732; P < 0.05). Plasma concentrations of arginine, betaine, histidine, and creatine were greater in supplemented birds than in their control counterparts, as were those of creatine, leucine and other essential amino acids at the hepatic level. In contrast, leucine concentration was lower in the caecal content of supplemented birds. Reduced alpha diversity and relative abundance of Firmicutes and Proteobacteria (specifically Escherichia coli), as well as increased abundance of Bacteroidetes and Lactobacillus salivarius were found in the caecal content of supplemented birds.

CONCLUSIONS

The improvement in growth performance corroborates the advantages of supplementing arginine in broiler nutrition. It can be hypothesized that the performance enhancement found in this study is associated with the increased availability of arginine, betaine, histidine, and creatine in plasma and the liver, as well as to the ability of extra dietary arginine to potentially ameliorate intestinal conditions and microbiota of supplemented birds. However, the latter promising property, along with other research questions raised by this study, deserve further investigations.

Amino Acid Requirements for Nile Tilapia: An Update

This review aims to consolidate the relevant published data exploring the amino acid (AA) requirements of Nile tilapia, Oreochromis niloticus, and to reach a new set of recommendations based on those data. There are still inconsistencies in lysine, sulfur-containing AA, threonine, tryptophan, branched-chain AA, and total aromatic AA recommendations in data that have appeared since 1988. This review finds that strain, size, basal diet composition, and assessment method may have contributed to the inconsistencies in AA recommendations. Currently, the expansion of precision AA nutrition diets for Nile tilapia is receiving more attention because of the demand for flexibility in widespread ingredient substitutions which will allow compliance with environmentally sustainable principles. Such approaches involve changes in diet ingredient composition with possible inclusions of non-bound essential and non-essential AAs. Increasing the inclusion of non-bound AAs into Nile tilapia diets may modify protein dynamics and influence AA requirements. Emerging evidence indicates that not only essential but also some non-essential amino acids regulate growth performance, fillet yield, and flesh quality, as well as reproductive performance, gut morphology, intestinal microbiota, and immune responses. Thus, this review considers current AA recommendations for Nile tilapia and proposes refinements that may better serve the needs of the tilapia industry.

Chemical Composition of Pigeon Crop Milk and Factors Affecting Its Production: A Review

Pigeons are important commercial poultry in addition to being ornamental birds. In 2021, more than 111 million pairs of breeding pigeons were kept in stock and 1.6 billion squabs were slaughtered for meat in China. However, in many countries, pigeons are not domestic birds; thus, it is necessary to elucidate the factors involved in their growth and feeding strategy due to their economic importance. Pigeons are altricial birds, so feedstuffs cannot be digested by squabs, which instead are fed a mediator named pigeon crop milk. During lactation, breeding pigeons (both female and male) ingest diets and generate crop milk to feed squabs. Thus, research on squab growth is more complex than that on chicken and other poultry. To date, research on the measurement of crop milk composition and estimation of the factors affecting its production has not ceased, and these results are worth reviewing to guide production. Moreover, some studies have focused on the formation mechanism of crop milk, reporting that the synthesis of crop milk is controlled by prolactin and insulin-activated pathways. Furthermore, the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 5 (STAT5) pathway, target of rapamycin (TOR) pathway and AMP-activated protein kinase (AMPK) pathway were also reported to be involved in crop milk synthesis. Therefore, this review focuses on the chemical composition of pigeon crop milk and factors affecting its production during lactation. This work explores novel mechanisms and provides a theoretical reference for improving production in the pigeon industry, including for racing, ornamental purposes, and production of meat products.

Effects of feeding rumen-protected methionine pre- and postpartum in multiparous Holstein cows: Health disorders and interactions with production and reproduction

Study objectives were to evaluate the effects of feeding rumen-protected Met (RPM) in pre- and postpartum total mixed rations (TMR) on health disorders and the interactions of health disorders with lactation and reproductive performance. Multiparous Holstein cows [470; 235 cows at University of Wisconsin (UW) and 235 cows at Cornell University (CU)] were enrolled at approximately 4 wk before parturition and housed in close-up dry cow (n = 6) and replicated lactation pens (n = 16). Pens were randomly assigned to treatment diets (pre- and postpartum, respectively): (1) control (CON): basal diet = 2.30% and 2.09% Met as % of metabolizable protein (MP) (UW) or 2.22% and 2.19% Met as % of MP (CU); (2) RPM: basal diet fed with RPM with 2.83% and 2.58% Met (Smartamine M, Adisseo Inc.; 12 g prepartum and 27 g postpartum), as % of MP (UW) or 2.85% and 2.65% Met (Smartamine M; 13 g prepartum and 28 g postpartum), as % of MP (CU). Total serum Ca was evaluated at the time of parturition and on d 3 ± 1 postpartum. Daily rumination was monitored from 7 d before parturition until 28 d postpartum. Health disorders were recorded during the experimental period until the time of first pregnancy diagnosis (32 d after timed artificial insemination; 112 ± 3 d in milk). Uterine health was evaluated on d 35 ± 3 postpartum. Time to pregnancy and herd exit were evaluated up to 350 d in milk. Treatment had no effect on the incidence of most health disorders and did not alter daily rumination. Cows fed RPM had reduced subclinical hypocalcemia (13.6 vs. 22%; UW only) on day of parturition relative to CON. Percentage of cows culled (13.1 vs. 19.3%) and hazard of herd exit due to culling [hazard ratio = 0.65, 95% confidence interval (CI): 0.42-1.02] tended to be reduced for cows fed RPM compared with CON. Moreover, cows fed RPM had greater milk protein concentration and protein yield overall, although retrospective analysis indicated that RPM only significantly increased protein yield in the group of cows with one or more health disorders (1.47 vs. 1.40 kg/d), not in cows without health disorders (1.49 vs. 1.46 kg/d) compared with CON. Overall, treatment had no effect on pregnancy per timed artificial insemination; however, among cows with health disorders, those fed RPM had reduced time to pregnancy compared with CON (hazard ratio = 0.71, 95% CI: 0.53-0.96). Thus, except for subclinical hypocalcemia on the day of parturition, feeding RPM in pre- and postpartum TMR did not reduce the incidence of health disorders, but our retrospective analysis indicated that it lessened the negative effects of health disorders on milk protein production and time to pregnancy.

Role of functional fatty acids in modulation of reproductive potential in livestock

Fatty acids are not only widely known as energy sources, but also play important roles in many metabolic pathways. The significance of fatty acids in modulating the reproductive potential of livestock has received greater recognition in recent years. Functional fatty acids and their metabolites improve follicular development, oocyte maturation and embryo development, as well as endometrial receptivity and placental vascular development, through enhancing energy supply and precursors for the synthesis of their productive hormones, such as steroid hormones and prostaglandins. However, many studies are focused on the impacts of individual functional fatty acids in the reproductive cycle, lacking studies involved in deeper mechanisms and optimal fatty acid requirements for specific physiological stages. Therefore, an overall consideration of the combination and synergy of functional fatty acids and the establishment of optimal fatty acid requirement for specific stages is needed to improve reproductive potential in livestock.

Free amino acid and acylcarnitine values in Ursus americanus Pallas 1780 (black bear) from Northeastern Mexico

INTRODUCTION

Ursus americanus Pallas 1780 is the largest carnivore and the only ursid in Mexico. It is considered an endangered species in the country because its distribution and population have been reduced by up to 80% because of habitat loss or furtive hunting. These problems can lead to a diet change, which could result in metabolic disorders, such as fatty acid β-oxidation defects or organic acid metabolism disorders. In our study, a free amino acid and acylcarnitine profile was characterized.

METHODS

Peripheral blood samples were drawn from nine free-ranging black bears in a period of five months, from June to October of 2019 in Northeastern Mexico, and 12 amino acids and 30 acylcarnitines were determined and quantified. Age differences were observed in the samples through ANOVA and post-hoc Tukey test.

RESULTS

Only three metabolites showed a significant difference with age: alanine (Ala) [cubs vs juvenile], free-carnitine (C0) [juvenile vs cubs] and acetylcarnitine (C2) [cubs vs adults and juvenile vs cubs].

CONCLUSION

Metabolites with variability due to age were identified, making them potential biomarkers to monitor metabolic status as early diagnosis in endangered species. This is the first study of black bear amino acid and acylcarnitine profiles, and the values found could be used as reference for free amino acid and acylcarnitine concentrations in further studies of the species.

Evaluation of standardized ileal digestibility of amino acids in fermented soybean meal for nursery pigs using direct and difference procedures

OBJECTIVE

This study was to evaluate standardized ileal digestibility (SID) of amino acids (AA) in fermented soybean meal (FSBM) for nursery pigs using both direct procedure and difference procedure when FSBM was added at 20% in diets.

METHODS

Forty-eight pigs at 9.2±0.9 kg body weight (BW) were individually housed and allotted to 4 treatments. Treatments included NFD (a semi-purified N free diet), FSD (a diet with 20% FSBM), CBD (corn basal diet), and CFD (corn basal diet:FSBM at 80:20). The FSD was used to measure AA digestibility in FSBM using the direct procedure, whereas CBD and CFD were used in the difference procedure. Pigs were fed for 10 days (0.09×BW0.75 kg per day) and euthanized to collect ileal digesta for TiO2 and AA.

RESULTS

Total endogenous AA loss was 12.1 g/kg of dry matter intake. The apparent ileal digestibility (AID) Thr was greater (p<0.05) and AID His (p = 0.073) and Leu (p = 0.052) tended to be greater using the direct procedure compared with the difference procedure. The SID Thr were greater (p<0.05) in FSBM for nursery pigs calculated using a direct procedure compared with a difference procedure. In addition, SID Lys in FSBM was about 83% to 88% for nursery pigs higher than SID Lys described in National Research Council (2012).

CONCLUSION

The SID of AA in FSBM when included at practical levels using the direct procedure were similar to those from the difference procedure. Considering the SID of AA obtained using both direct and difference procedures, FSBM is an effective protein supplement providing highly digestible AA to nursery pigs. The SID of AA from this study was considerably higher than those previous reported. This study also indicates the importance of including the test feedstuffs at practical levels when evaluating digestibility.

Effects of arginine replacement with L-citrulline on the arginine/nitric oxide metabolism in chickens: An animal model without urea cycle

BACKGROUND

This study examined the efficacy of L-citrulline supplementation on the arginine/nitric oxide metabolism, and intestinal functions of broilers during arginine deficiency. A total of 288 day-old Arbor Acre broilers were randomly assigned to either an arginine deficient basal diet (NC diet), NC diet + 0.50% L-arginine (PC diet), or NC diet + 0.50% L-citrulline (NCL diet). Production performance was recorded, and at 21 days old, chickens were euthanized for tissue collection.

RESULTS

The dietary treatments did not affect the growth performance of broilers (P > 0.05), although NC diet increased the plasma alanine aminotransferase, urate, and several amino acids, except arginine (P < 0.05). In contrast, NCL diet elevated the arginine and ornithine concentration higher than NC diet, and it increased the plasma citrulline greater than the PC diet (P < 0.05). The nitric oxide concentration in the kidney and liver tissues, along with the plasma and liver eNOS activities were promoted by NCL diet higher than PC diet (P < 0.05). In the liver, the activities of arginase 1, ASS, and ASL, as well as, the gene expression of iNOS and OTC were induced by PC diet greater than NC diet (P < 0.05). In the kidney, the arginase 1, ASS and ASL enzymes were also increased by PC diet significantly higher than the NC and NCL diets. Comparatively, the kidney had higher abundance of nNOS, ASS, ARG2, and OTC genes than the liver tissue (P < 0.05). In addition, NCL diet upregulated (P < 0.05) the mRNA expression of intestinal nutrient transporters (EAAT3 and PEPT1), tight junction proteins (Claudin 1 and Occludin), and intestinal mucosal defense (MUC2 and pIgR). The intestinal morphology revealed that both PC and NCL diets improved (P < 0.05) the ileal VH/CD ratio and the jejunal VH and VH/CD ratio compared to the NC fed broilers.

CONCLUSION

This study revealed that NCL diet supported arginine metabolism, nitric oxide synthesis, and promoted the intestinal function of broilers. Thus, L-citrulline may serve as a partial arginine replacement in broiler's diet without detrimental impacts on the performance, arginine metabolism and gut health of chickens.

Bee Pollen and Bread as a Super-Food: A Comparative Review of Their Metabolome Composition and Quality Assessment in the Context of Best Recovery Conditions

Recently, functional foods have been a subject of great interest in dietetics owing not only to their nutritional value but rather their myriad of health benefits. Moreover, an increase in consumers' demands for such valuable foods warrants the development in not only production but rather tools of quality and nutrient assessment. Bee products, viz., pollen (BP) and bread, are normally harvested from the flowering plants with the aid of bees. BP is further subjected to a fermentation process in bee hives to produce the more valuable and bioavailable BB. Owing to their nutritional and medicinal properties, bee products are considered as an important food supplements rich in macro-, micro-, and phytonutrients. Bee products are rich in carbohydrates, amino acids, vitamins, fatty acids, and minerals in addition to a myriad of phytonutrients such as phenolic compounds, anthocyanins, volatiles, and carotenoids. Moreover, unsaturated fatty acids (USFAs) of improved lipid profile such as linoleic, linolenic, and oleic were identified in BP and BB. This work aims to present a holistic overview of BP and BB in the context of their composition and analysis, and to highlight optimized extraction techniques to maximize their value and future applications in nutraceuticals.

Differential Effects of Oligosaccharides, Antioxidants, Amino Acids and PUFAs on Heat/Hypoxia-Induced Epithelial Injury in a Caco-2/HT-29 Co-Culture Model

(1) Exposure of intestinal epithelial cells to heat and hypoxia causes a (heat) stress response, resulting in the breakdown of epithelial integrity. There are indications that several categories of nutritional components have beneficial effects on maintaining the intestinal epithelial integrity under stress conditions. This study evaluated the effect of nine nutritional components, including non-digestible oligosaccharides (galacto-oligosaccharides (GOS), fructo-oligosaccharides (FOS), chitosan oligosaccharides (COS)), antioxidants (α-lipoic acid (ALA), resveratrol (RES)), amino acids (l-glutamine (Glu), l-arginine (Arg)) and polyunsaturated fatty acids (PUFAs) (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)), on heat/hypoxia-induced epithelial injury. (2) Two human colonic cell lines, Caco-2 and HT-29, were co-cultured and pre-treated with the nutritional components for 48 h. After pre-treatment, the cells were exposed to heat/hypoxia (42 °C, 5% O₂) for 2 h. Epithelial integrity was evaluated by measuring trans-epithelial electrical resistance (TEER), paracellular Lucifer Yellow (LY) permeability, and tight junction (TJ) protein expression. Heat stress and oxidative stress levels were evaluated by determining heat-shock protein-70 (HSP-70) expression and the concentration of the lipid peroxidation product malondialdehyde (MDA). (3) GOS, FOS, COS, ALA, RES, Arg, and EPA presented protective effects on epithelial damage in heat/hypoxia-exposed Caco-2/HT-29 cells by preventing the decrease in TEER, the increase in LY permeability, and/or decrease in TJ proteins zonula occludens-1 (ZO-1) and claudin-3 expression. COS, RES, and EPA demonstrated anti-oxidative stress effects by suppressing the heat/hypoxia-induced MDA production, while Arg further elevated the heat/hypoxia-induced increase in HSP-70 expression. (4) This study indicates that various nutritional components have the potential to counteract heat/hypoxia-induced intestinal injury and might be interesting candidates for future in vivo studies and clinical trials in gastrointestinal disorders related to heat stress and hypoxia.

Dietary glycine supplementation enhances postweaning growth and meat quality of pigs with intrauterine growth restriction

Pigs with intrauterine growth restriction (IUGR) have suboptimum growth performance and impaired synthesis of glycine (the most abundant amino acid in the body). Conventional corn- and soybean meal-based diets for postweaning pigs contain relatively low amounts of glycine and may not provide sufficient glycine to meet requirements for IUGR pigs. This hypothesis was tested using 52 IUGR pigs and 52 litter mates with normal birth weights (NBW). At weaning (21 d of age), IUGR or NBW pigs were assigned randomly to one of two nutritional groups: supplementation of a corn-soybean meal-based diet with either 1% glycine plus 0.19% cornstarch or 1.19% L-alanine (isonitrogenous control). Feed consumption and body weight (BW) of pigs were recorded daily and every 2 or 4 wks, respectively. All pigs had free access to their respective diets and clean drinking water. Within 1 wk after the feeding trial ended at 188 d of age, blood and other tissue samples were obtained from pigs to determine concentrations of amino acids and meat quality. Neither IUGR nor glycine supplementation affected (P > 0.05) feed intakes of pigs per kg BW. The final BW, gain:feed ratio, carcass dressing percentages, and four-lean-cuts percentages of IUGR pigs were 13.4 kg, 4.4%, 2%, and 15% lower (P < 0.05) for IUGR pigs than NBW pigs, respectively. Compared with pigs in the alanine group, dietary glycine supplementation increased (P < 0.05) final BW, gain:feed ratio, and meat a* value (a redness score) by 3.8 kg, 11%, and 10%, respectively, while reducing (P < 0.05) backfat thickness by 18%. IUGR pigs had lower (P < 0.05) concentrations of glycine in plasma (-45%), liver (-25%), jejunum (-19%), longissimus dorsi muscle (-23%), gastrocnemius muscle (-26%), kidney (-15%), and pancreas (-6%), as compared to NBW pigs. In addition, dietary glycine supplementation increased (P < 0.05) concentrations of glycine in plasma and all analyzed tissues. Thus, supplementing 1% of glycine to corn-soybean meal-based diets improves the growth performance, feed efficiency, and meat quality of IUGR pigs.

The Potential of Rhizobacteria to Mitigate Abiotic Stress in Lessertia frutescens

Lessertia frutescens is a multipurpose medicinal plant indigenous to South Africa. The curative ability of the medicinal plant is attributed to its rich phytochemical composition, including amino acids, triterpenoids, and flavonoids. A literature review of some of the phytochemical compounds, particularly amino acids, in L. frutescens shows a steady decrease in concentration over the years. The reduction of the phytochemical compounds and diminishing biological activities may be attributed to drought and salt stress, which South Africa has been grappling with over the years. Canavanine, a phytochemical which is associated with the anticancer activity of L. frutescens, reduced slightly when the plant was subjected to salt stress. Like other legumes, L. frutescens forms a symbiotic relationship with plant-growth-promoting rhizobacteria, which facilitate plant growth and development. Studies employing commercial plant-growth-promoting rhizobacteria to enhance growth and biological activities in L. frutescens have been successfully carried out. Furthermore, alleviation of drought and salt stress in medicinal plants through inoculation with plant growth-promoting-rhizobacteria is well documented and effective. Therefore, this review seeks to highlight the potential of plant-growth-promoting rhizobacteria to alleviate the effect of salt and drought in Lessertia frutescens.

Impact of L-Arginine and L-Glutamine supplementation on growth performance and immune status in weanling pigs challenged with Escherichia coli F4

Arginine (ARG) and Glutamine (GLN) have been reported to play significant roles in protein metabolism, immunity, and intestinal health in weanling pigs. The present study investigated the independent and interactive effect of supplementing ARG and GLN on pigs immune status and growth performance following an Escherichia coli F4 challenge. A total of 240 mixed-sex pigs (24 ± 2 d old; 7.3 ± 0.1 kg BW) were used in a 42-d experiment after selection for E. coli F4 susceptibility. The pigs were group-housed (3 pigs per pen), and pens were randomly assigned to five experimental treatments (N = 16 pens per treatment). Experimental treatments were: 1) a wheat-barley-soybean meal-based basal diet (CTRL), 2) a basal diet with 2500 mg/kg zinc oxide (ZnO), 3) a basal diet + 0.5% Glutamine (0.5% GLN), 4) basal diet + 0.5% Arginine (0.5% ARG), and 5) basal diet with 0.5% Glutamine + 0.5% Arginine (0.5% GLN + ARG). All Pigs were inoculated with E. coli F4 on days 7, 8, and 9 post-weaning. Rectal swabs were taken from each pig and plated on blood agar plates for E. coli F4 presence. Blood and fecal samples were taken to determine the acute phase response and selected fecal biomarkers for the immune response. Growth performance and fecal scores were recorded. Fecal swabs resulted in no positive pig for E. coli F4 before inoculation and 73.3% positive postinoculation. Diarrhea incidence during days 7 to 14 was significantly lower for the ZnO treatment (P < 0.05). The haptoglobin level on day 3 was lower than days 10 and 20, irrespective of treatment (P < 0.05). The albumin level was lower on day 20 compared to days 3 and 10 (P < 0.05). There was no treatment effect on albumin levels regardless of sampling day (P > 0.05). The PigMAP was lowest on day 3 and highest on day 10 (P < 0.05). We did not observe significant treatment differences (P > 0.05) in myeloperoxidase and calprotectin. Pancreatitis-associated protein was higher in the ZnO (P = 0.001) treatment than in the other treatments. Fecal IgA tended (P = 0.10) to be higher in the ZnO and 0.5% ARG treatments. There were no performance differences, except during days 0 to 7, where the ZnO treatment was lower in average daily gain and average daily feed intake (P < 0.001), while feed efficiency (G:F) FE was similar across treatments. In summary, no improved performance was observed with either ARG, glutamate, or both. The immune response results showed that the E. coli F4 challenge may have exacerbated the acute phase response; hence, the benefits of dietary treatments did not go beyond immune repair and reduction in inflammation.

Functional properties of amino acids: improve health status and sustainability

The combination of increased genetic potential and changes in management strategies (i.e., antibiotic-free, no antibiotics ever, and every day feeding of replacement pullets) influences the nutritional needs of poultry. Traditionally, nutritionists have focused on meeting the amino acid needs for production performance and yield however, increasing specific amino acid concentrations can benefit gastrointestinal development and integrity, enhance immune response potential, influence behavior, and benefit sustainability. Commercialization of additional feed grade amino acids beyond methionine, lysine, and threonine, enables targeted increases to achieve these benefits. As such, this paper addresses the functional roles of amino acids in meeting poultry production, health, and sustainability goals.

Low-protein diets supplemented with glycine improves pig growth performance and meat quality: An untargeted metabolomic analysis

For the purpose to improve meat quality, pigs were fed a normal diet (ND), a low protein diet (LPD) and a LPD supplemented with glycine (LPDG). Chemical and metabolomic analyses showed that LPD increased IMF deposition and the activities of GPa and PK, but decreased glycogen content, the activities of CS and CcO, and the abundance of acetyl-CoA, tyrosine and its metabolites in muscle. LPDG promoted muscle fiber transition from type II to type I, increased the synthesis of multiple nonessential amino acids, and pantothenic acid in muscle, which should contributed to the improved meat quality and growth rate. This study provides some new insight into the mechanism of diet induced alteration of animal growth performance and meat quality. In addition, the study shows that dietary supplementation of glycine to LPD could be used to improved meat quality without impairment of animal growth.

Optimal dietary standardized ileal digestible lysine level for pigs during the grower, early and late finisher periods

BACKGROUND

Lysine (Lys) is the first limiting amino acid for pigs fed corn-soybean meal diets. Three experiments were conducted to estimate the optimal standardized ileal digestible (SID) Lys requirement for growing (Exp. 1), early finishing (Exp. 2), and late finishing (Exp. 3) pigs under commercial conditions.

RESULTS AND CONCLUSIONS

In Exp. 1, a total of 650 growing pigs (32.21 ± 0.33 kg bodyweight), were allocated to 5 dietary treatments supplemented with 0.75, 0.85, 0.94, 1.03, and 1.13% SID Lys. Each treatment had 5 replicate pens with 26 pigs per pen. The lowest feed to gain ratio (F:G) was obtained by pigs fed the 1.03% Lys diet and F:G showed both a linear and a quadratic response with increasing Lys (P < 0.05). Based on broken-line and quadratic analysis models, dietary SID Lys levels for the minimum F:G were 0.94%. In Exp. 2, 650 finishing pigs (57.24 ± 2.00 kg bodyweight) were allotted to 5 dietary treatments providing SID Lys of 0.63, 0.71, 0.79, 0.87, and 0.95%. Each treatment had 5 replicates, 26 pigs per replication. The highest final bodyweight was achieved by 0.79% Lys while the highest average daily gain (ADG) and average daily feed intake (ADFI) was achieved by pigs consuming the 0.87% Lys diet (P < 0.05). Additionally, the lowest F:G was obtained by pigs fed the 0.79 and 0.87% Lys diet (P < 0.05). Based on broken-line and quadratic analysis models, the optimum Lys was 0.81 and 0.82% for ADG and F:G, respectively. In Exp. 3, 600 late finishing pigs (92.22 ± 2.41 kg bodyweight), were divided into 5 treatments providing Lys levels of 0.53, 0.60, 0.66, 0.73, and 0.79%. Each treatment had 5 replicates, 24 pigs per replication. Results showed that final bodyweight, ADG, ADFI, and F:G was not affected by increasing dietary Lys level, suggesting that the lowest SID Lys (0.53%) was sufficient for this group of pigs. Taken together, the SID Lys requirement for pigs from 30 to 60 kg, 60 to 90 kg, 90 to 120 kg was 0.94%, 0.81 to 0.82, and 0.53%, respectively, depending on the response criteria with performance maximized.

Non-invasive evaluation of embryos using mid-infrared attenuated total reflection spectrometry of incubation medium: a preliminary study

RESEARCH QUESTION

Can mid-infrared attenuated total reflection (MIR ATR) spectroscopy combined with machine learning methods be used as an additional tool to predict embryo quality and IVF treatment outcomes?

DESIGN

Spent culture media was collected and analysed. MIR ATR absorbance spectra were measured using an ALPHA II spectrometer equipped with an attenuated total reflection (ATR) spectrometry accessory. Patient and treatment data and results were collected and analysed in combination with machine learning techniques to identify possible correlations. The main outcome measures were to define the characteristics of absorbance spectra of spent culture media and to distinguish the difference in absorbance between top- and low-quality embryos, day 3 and day 5 embryos and implanting embryos versus non-implanting embryos.

RESULTS

Spent culture media of 227 embryos was collected and analysed. Absorbance peaks in the culture media were different between day 3 and day 5 embryos. Moreover, significant differences in P-values, spanning from 0.014 to 0.044 in absorbance peaks for day 3 embryos and 0.024 up to 0.04 for day 5 embryos, were seen between implanting and non-implanting embryos. Machine learning techniques offered a pregnancy prediction value of 84.6% for day 3 embryos.

CONCLUSIONS

MIR ATR may offer an additional parameter for better selection of embryos based on the spectrometric absorbance and secretions of metabolites in the culture media.

MOLECULAR MECHANISMS DEFINING APPLICATION OF GLYCINE AND ZINC COMBINATIONIN CORRECTION OF STRESS AND ANXIETY MAIN MANIFESTATIONS

The aim of the work was to carry out a systematic analysis of the molecular mechanisms that determine the possibility of a combined use of amino acid glycine and zinc compounds for the treatment of patients with manifestations of stress and anxiety.

Materials and methods. Information retrieval (Scopus, PubMed) and library (eLibrary) databases were used as research tools. In some cases, the ResearchGate application was applied for a semantic search. The analysis and generalization of references was carried out on the research topic, covering the period from 2000 to the present time.

Results. It has been shown that amino acid glycine, along with gamma-aminobutyric acid (GABA), is a key neurotransmitter that regulates physiological inhibition processes in the central nervous system (CNS) by increasing transmembrane conductance in specific pentameric ligand-gated ion channels. The introduction of zinc ions can potentiate the opening of these receptors by increasing their affinity for glycine, resulting in an inhibitory processes increase in CNS neurons. The replenishment of the glycine and zinc combined deficiency is an important element in the correction of a post-stress dysfunction of the central nervous system. A balanced intake of zinc and glycine is essential for most people who experience daily effects of multiple stresses and anxiety. This combination is especially useful for the people experiencing a state of chronic psycho-emotional stress and maladaptation, including those who have a difficulty in falling asleep.

Conclusion. A balanced maintenance of the zinc and glycine concentration in the body of a healthy person leads to the development of a stable anti-anxiety effect, which is accompanied by the normalization of the sleep-wake rhythm, which makes it possible to have a good rest without any loss of working efficiency after waking up.