Addition Of Essential Amino Acids Research Articles

GCN2 eIF2 kinase promotes prostate cancer by maintaining amino acid homeostasis.

A stress adaptation pathway termed the integrated stress response has been suggested to be active in many cancers including prostate cancer (PCa). Here, we demonstrate that the eIF2 kinase GCN2 is required for sustained growth in androgen-sensitive and castration-resistant models of PCa both in vitro and in vivo, and is active in PCa patient samples. Using RNA-seq transcriptome analysis and a CRISPR-based phenotypic screen, GCN2 was shown to regulate expression of over 60 solute-carrier (SLC) genes, including those involved in amino acid transport and loss of GCN2 function reduces amino acid import and levels. Addition of essential amino acids or expression of 4F2 (SLC3A2) partially restored growth following loss of GCN2, suggesting that GCN2 targeting of SLC transporters is required for amino acid homeostasis needed to sustain tumor growth. A small molecule inhibitor of GCN2 showed robust in vivo efficacy in androgen-sensitive and castration-resistant mouse models of PCa, supporting its therapeutic potential for the treatment of PCa.

​Effect of Chemically Amended Litter and Supplementing Low Protein Diet with Amino Acids on Immune Status, Carcass Characteristics, Biochemical Parameters and Broiler Chicken Behavior during Summer

Background: Ammonia gas present in poultry shed critically affects the health and welfare condition of bird and the labourer which are working at the poultry farm. Good litter management and low protein diet minimize the ammonia concentration resulting in overall improvement of the bird’s welfare. The current study was aimed to estimate the effect of alum sulphate in litter and addition of essential amino acids in a low protein diet on immunity status, serum biochemical parameters, carcass parameters and behavior welfare of broiler chicks. Methods: A total of 240 (day old) Vencobb broiler chicks were randomly distributed into four treatment groups, having 3 replicates of 20 chicks each. Control group (Tc) had no dietary and litter amendments, whereas, experiment groups include litter amendment with alum sulphate @ 90 gm/sq.ft. (TL) dietary amendment with low protein supplemented with essential amino acids like lysine, methionine, threonine (TD) and both dietary and litter amendment (TLD). Result: The results showed that immune status was better in the litter treated groups as compare to control and TD group. The overall hygiene of the birds was better in treatment groups. It can be concluded that treatment of litter with alum sulphate improved protein metabolism and carcass quality and also help in providing a comfortable environment to the broiler birds.

Metabolic effects of high-intensity interval training and essential amino acids.

High-intensity interval training (HIIT) promotes positive cardiometabolic and body composition changes. Essential amino acids (EAA) may support changes associated with HIIT, but evaluation of potential synergistic effects is lacking. The purpose of this study was to compare independent and combined effects of HIIT and EAA on total body composition and metabolism in men and women considered overweight/obese; an exploratory aim was to evaluate the modulatory effects of sex. Sixty-six healthy adults (50% female; Age: 36.7 ± 6.0 years; BMI: 32.0 ± 4.2kg/m2) completed 8 weeks of: (1) HIIT, 2 days/weeks; (2) EAA supplementation, 3.6g twice daily; (3) HIIT + EAA; or (4) control. Body composition, resting metabolic rate (RMR), substrate metabolism (respiratory exchange ratio; RER), and cardiorespiratory fitness were measured at baseline, 4 weeks, and 8 weeks; cardiometabolic blood markers were measured at baseline and 8 weeks. Differences between groups were assessed by linear mixed models covaried for baseline values, followed by 95% confidence intervals (CI) on adjusted mean change scores. There were no significant changes in body composition (p > 0.05) for any group. Changes in RER, but not RMR, occurred with HIIT (mean change; [95% CI]: - 0.04; [- 0.07, - 0.02]) and EAA (- 0.03; [- 0.06, - 0.01]) after 8 weeks. Cardiorespiratory fitness increased following 8 weeks of HIIT (+ 5.1ml/kg/min [3.3,6.8]) and HIIT + EAA (+ 4.1ml/kg/min [1.0,6.4]). Changes with HIIT + EAA were not significantly different from HIIT. There were no changes in cardiometabolic markers (p > 0.05) and no sex interaction (p > 0.05). HIIT is efficacious for promoting positive changes in cardiorespiratory fitness and resting substrate metabolism in adults considered overweight/obese. Addition of EAA did not significantly enhance HIIT-induced adaptations. ClinicalTrials.gov ID#NCT04080102.

Effect of Lysine Supplementation in Commercial Feed on Energy Retention and Feed Conversion Ratio of Carp (Osphronemus gouramy)

The long period of raising carp (Osphronemus gouramy) causes the need for excessive feed. One way that can accelerate the growth of this fish in order to shorten the maintenance period is by the addition of essential amino acids, such as lysine. However, this certainly gives its own influence on energy retention. Therefore, the aim of this study was to determine the influences of addition of lysine in feed on energy retention and feed conversion ratio of carp. The research method used an experimental method with a completely randomized design consisting of five treatments and four replications. The treatments used were the addition of Lysine 0%, 1%, 1.5%, 2%, and 2.5% to the feed. The present experiment was conducted for a year. The results showed that the addition of lysine as much as 2% in commercial feed can increase the energy retention of carp (Osphronemus gouramy). Moreover, the addition of lysine by giving up to 2.5% cannot reduce the feed conversion ratio in carp (Osphronemus gourami) rearing. It can be concluded that the use of lysine has different effects related to the increase in retention and decrease conversion ratio in carp.

GLOBIGEN JUMP START APPLICATION WITHIN THE PRE-STARTER FEED TO THE POST-WAENING PIGLETS

Balanced addition of essential amino acids, vitamins and minerals, easily digestible proteins, namely proteins of animal origin is an important factor for efficient feeding and pigs performance, that leads to a systematic search for new solutions when using feed additives. They provide digestibility, better absorbtion of protein, vitamins, minerals and other nutrients. Such supplements include blood plasma, meat and bone meal, fish meal and others.
 Besides fishmeal, other protein groups are dangerous in relation to African swine fever. Furthermore blood plasma additionally to the protein group contains immunoglobulins that can passively affect the immune system of piglets, An alternative to blood plasma is the animal nutrition supplement Globigen Jump Start, which is made from chicken eggs, containing essential and replaceable amino acids with a high percentage of absorption. Another important factor is the presence of specific IgY immuno-globulins, which being ingested have a negative effect on the pathogenic intestinal microflora, namely viruses, bacteria and cryptosporidium. Knowledge of the feed additive Globigen Jump Start effect gave impetus to the study of its effect on the piglets’ performance during the stressful period after weaning.
 The objective of the work was evaluation of the effect of the Globigen Jump Start fed within the pre-starter feed on the productive characteristics of post-weaning piglets. Based on the obtained research results, the best ones were shown in the experimental group, which was fed compound feed containing Globigen Jump Start in the amount of 2 kg / t of compound feed. It was found that at the end of the experiment, the weight of piglets in the control group was 19.2 kg, and in the experimental group - 21.0 kg, which is 1.8 kg or 9.4% more comparing to the control.

Phytocorrection of biochemical status and productivity when fattening barrows on low-protein diets enriched with essential amino acids

The effect of the plant ecdysteroid-containing preparation of Leuzea extract on the metabolism and productivity of barrows (three-breed crossbreeds Landrace × large white × Duroc) during fattening on low-protein diets enriched with essential amino acids from 130 to 212 days old was studied for the first time. In the control and experimental groups, a low-protein barley-wheat diet with the addition of essential amino acids contained (g / kg) crude protein - 108 g, metabolic energy - 12.5 MJ, lysine - 7.6 g, threonine - 5.4 g, methionine - 5.2 g. In the experimental group, liquid extract of leuzea was introduced into the feed, at the rate of 190 mg / kg. Feeding the barrows during the fattening period of the leuzea extract contributed to an increase in the efficiency of the use of nutrients in biosynthetic processes in animals. In the barrows of the experimental group, the concentrations of total protein (P≤0.05), albumin (P≤0.05), creatinine (P≤0.05), lactate dehydrogenase, creatine kinase, alkaline phosphatase activity at a lower level were statistically significantly higher urea (16.1%, P≤0.05) and glucose (P≤0.05). In the experimental group, during the period of fattening, the average daily gain in live weight was higher (by 10.2%, P≤0.05), the yield in the carcass of muscle tissue (P≤0.05), the indices of lean and meatiness, and lower the cost of feed (P≤ 0.05), crude protein (P≤0.05) and exchange energy (P≤0.05) per 1 kg of gain in live weight, output of subcutaneous adipose tissue and internal fat in comparison with the control. It was concluded that the use of a leuzea extract containing phytoecdysteroids, while feeding low-protein diets enriched with lysine, methionine and threonine, corrects metabolic processes, stimulating the biosynthesis of meat components, and thereby contributes to an increase in the productivity of barrows during fattening.

Amino acid starvation culture condition sensitizes EGFR-expressing cancer cell lines to gefitinib-mediated cytotoxicity by inducing atypical necroptosis.

The maintenance of the intracellular level of amino acids is crucial for cellular homeostasis. This is carried out via the regulation of both the influx from the extracellular environment and the recycling of intracellular resources. Since epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors, including gefitinib (GEF) have been reported to induce the apoptosis of several cancer cell lines, in the present study, we examined whether the cytotoxic effects of GEF are further enhanced under amino acid starvation (AAS) culture conditions. Under AAS culture conditions, the cell killing effect of GEF was synergistically pronounced in the EGFR-expressing cell lines, namely, CAL 27, Detroit 562, A549 and PANC-1 cells compared with those treated with either GEF or AAS alone. The addition of essential amino acids, but not non-essential amino acids to the cell culture medium resulted in the cancellation of this pronounced cytotoxicity. The knockdown of L-type amino acid transporter 1 (LAT-1) by siRNA also enhanced GEF-induced cytotoxicity. Therefore, the shortage of the intracellular amino acid pool appears to determine the sensitivity to GEF. Notably, this enhanced cytotoxicity is not mediated by the induction of apoptosis, but is accompanied by the pronounced induction of autophagy. The presence of necrostatin-1, an inhibitor of receptor-interacting serine/threonine-protein kinase 1 (RIPK-1), but not that of Z-VAD-fmk, attenuated the cytotoxic effects of GEF under AAS culture conditions. Electron microscopy demonstrated that the CAL 27 cells treated with GEF under AAS culture conditions exhibited swelling of the cytosol and organelles with an increased number of autophagosomes and autolysosomes, but without chromatin condensation and nuclear fragmentation. Autophagic cell death was excluded as the inhibition of autophagy did not attenuate the cytotoxicity. These results strongly suggest the induction of necroptosis in response to GEF under AAS culture conditions. However, we could not detect any phosphorylation of RIPK-1 and mixed lineage kinase domain like pseudokinase (MLKL), as well as any necrosome formation. Therefore, the enhanced cytotoxic effect of GEF under AAS culture conditions is thought to be mediated by atypical necroptosis.

Dietary essential amino acids affect the reproduction of the keystone herbivore Daphnia pulex.

Recent studies have indicated that nitrogen availability can be an important determinant of primary production in freshwater lakes and that herbivore growth can be limited by low dietary nitrogen availability. Furthermore, a lack of specific essential nitrogenous biochemicals (such as essential amino acids) might be another important constraint on the fitness of consumers. This might be of particular importance for cladoceran zooplankton, which can switch between two alternative reproductive strategies – the production of subitaneously developing and resting eggs. Here, we hypothesize that both the somatic growth and the type of reproduction of the aquatic keystone herbivore Daphnia is limited by the availability of specific essential amino acids in the diet. In laboratory experiments, we investigated this hypothesis by feeding a high quality phytoplankton organism (Cryptomonas) and a green alga of moderate nutritional quality (Chlamydomonas) to a clone of Daphnia pulex with and without the addition of essential amino acids. The somatic growth of D. pulex differed between the algae of different nutritional quality, but not dependent on the addition of dissolved amino acids. However, in reproduction experiments, where moderate crowding conditions at saturating food quantities were applied, addition of the essential amino acids arginine and histidine (but not lysine and threonine) increased the total number and the developmental stage of subitaneous eggs. While D. pulex did not produce resting eggs on Cryptomonas, relatively high numbers of resting eggs were released on Chlamydomonas. When arginine and histidine were added to the green algal diet, the production of resting eggs was effectively suppressed. This demonstrates the high, but previously overlooked importance of single essential amino acids for the reproductive strategy of the aquatic keystone herbivore Daphnia.

Genetic variation of dietary restriction and the effects of nutrient-free water and amino acid supplements on lifespan and fecundity ofDrosophila

We measure genetic variation in lifespan and fecundity at two food levels in 34 core lines of the Drosophila Genetic Reference Panel collection. Lines were significantly different from each other in lifespan and fecundity at both restricted and full food. There was a strong food-by-line interaction for the slope of age-specific mortality, fecundity and proportion of fertilized eggs, indicating the presence of genetic variation for the strength of the dietary restriction effect, likely to represent standing genetic variation in a natural population from which the lines used have originated. No trade-off between fecundity and lifespan manifested in life-history variation among inbred lines. Our data partially corroborate the recent proposition that availability of nutrient-free water eliminates the apparent dietary restriction at least in some conditions. Although flies on full food with water added had lifespan slightly higher than those without a water source, it was still significantly lower than that in flies on restricted food, with no indication of interaction. We fully corroborate the recently discovered effect of addition of essential amino acids to the medium: addition of 1.5 mM methionine to restricted food significantly increased fecundity without a measurable decrease in lifespan; addition of each of 10 essential amino acids increased fecundity and decreased females lifespan to the levels observed on full food, again with no evidence of line-by-food interactions. We propose a mechanistic hypothesis explaining the observed data, based on the assumption that food consumption by flies is adjusted according to flies' saturation in water and methionine.

Adding Essential Amino Acids at a Low Concentration Improves the Development of In Vitro Fertilized Porcine Embryos

The aims of this study were to investigate improvements to the pig preimplantation embryo culture system using in vitro produced embryos. For experiment 1, the optimum time to change the medium from NCSU23 containing 0.6 mM glucose, 0.2 mM pyruvate, 5.7 mM lactate and nonessential amino acids to NCSU23 containing 5.6 mM glucose and both essential and nonessential amino acids was examined. There were no statistically significant differences in blastocyst rates or cell number when the medium was changed at 48, 72 or 96 h, although there was a consistent trend for the 96 h treatment to produce fewer blastocysts with fewer cells. For experiment 2, the addition of essential amino acids at either a 1:50 or a 1:100 dilution of the purchased stock solution for day 1 to 6 or for days 3 to 6 only was investigated. Adding essential amino acids at a 1:50 dilution for day 3 to 6 significantly reduced the blastocyst rate and adding them at a 1:50 dilution from day 1 to 6 significantly reduced both the blastocyst rate and blastocyst cell number compared to when it was added at a 1:100 dilution. Embryos were produced by IVF, cultured for 6 days and good quality blastocysts were transferred into 6 synchronized pseudopregnant recipients (24 to 35 blastocysts per recipient) resulting in 4 pregnancies and 21 live birth piglets. These results show that adding essential amino acids at a 1:100 dilution provided the best culture conditions and the blastocysts produced were able to attain full term development after transfer.

MVps34 is activated following high‐resistance contractions

Following resistance exercise in the fasted state, both protein synthesis and degradation in skeletal muscle are increased. The addition of essential amino acids potentiates the synthetic response suggesting that an amino acid sensor, which is involved in both synthesis and degradation, may be activated by resistance exercise. One such candidate protein is the class 3 phosphatidylinositol 3OH-kinase (PI3K) Vps34. To determine whether mammalian Vps34 (mVps34) is modulated by high-resistance contractions, mVps34 and S6K1 (an index of mTORC1) activity were measured in the distal hindlimb muscles of rats 0.5, 3, 6 and 18 h after acute unilateral high-resistance contractions with the contralateral muscles serving as a control. In the lengthening tibialis anterior (TA) muscle, S6K1 (0.5 h = 366.3 +/- 112.08%, 3 h = 124.7 +/- 15.96% and 6 h = 129.2 +/- 0%) and mVps34 (3 h = 68.8 +/- 15.1% and 6 h = 36.0 +/- 8.79%) activity both increased, whereas in the shortening soleus and plantaris (PLN) muscles the increase was significantly lower (PLN S6K1 0.5 h = 33.1 +/- 2.29% and 3 h = 47.0 +/- 6.65%; mVps34 3 h = 24.5 +/- 7.92%). HPLC analysis of the TA demonstrated a 25% increase in intramuscular leucine concentration in rats 1.5 h after exercise. A similar level of leucine added to C2C12 cells in vitro increased mVps34 activity 3.2-fold. These data suggest that, following high-resistance contractions, mVps34 activity is stimulated by an influx of essential amino acids such as leucine and this may prolong mTORC1 signalling and contribute to muscle hypertrophy.

Nitrogen balance in barrows fed low-protein diets supplemented with essential amino acids

Abstract This study was conducted to determine the effect of addition of essential amino acids (EAA) to low-protein diets on N balance in barrows. Thirty barrows (Duroc × Yorkshire) with an initial BW of 36 kg were fed 5 corn- and soybean meal-based diets containing 13.6 to 18.2% crude protein (CP) for 10 d in a randomized complete block design. The 18.2% CP diet was formulated without addition of EAA (Lys, Met or Thr). The other diets contained 13.6 to 16.5% CP and were supplemented with EAA to provide 0.83% true digestible lysine equal to that in the 18.2% CP diet. Fecal, urinary, and total N excretion as well as N retention (g/d) decreased with decreasing dietary CP level (P

Ascorbate Offsets the Inhibitory Effect of Inositol Phosphates on Iron Uptake and Transport by Caco-2 Cells

Differentiated monolayer cultures of Caco-2 human intestinal cells were used as a model to examine interactions between various dietary factors related to the intestinal uptake and absorption of nonheme Fe. Caco-2 cells accumulated 91-98 pmol Fe/mg protein from uptake buffer containing 12 nmol of Fe(III)-nitrilotriacetate during a 1-hr incubation at 37 degrees C. Addition of a 10-fold molar excess of inositol hexaphosphate (IP6) and its lesser phosphorylated derivatives (IP3, IP4, and IP5) decreased cellular uptake and transport of Fe from the lumenal compartment. Addition of ascorbic acid (AA) to the solution containing IPs stimulated Fe uptake and transport in a manner dependent upon the ratio of AA to IP and inversely proportional to the degree of phosphorylation of inositol (i.e., IP3 > IP4 > IP5 > IP6). A mixture of essential amino acids had minimal impact on Fe uptake in either the absence or presence of IPs. Cellular acquisition of Fe from solutions containing IPs was further enhanced by simultaneous addition of essential amino acids and AA. The stimulatory influence of ascorbic acid on Fe uptake from solutions containing IP6 was associated with an increase in the level of ferrous ion. These data further support the usefulness of Caco-2 cells as a model for investigating the effects of various dietary factors on mineral bioavailability.

Amino acid-rich medium (Leibovitz L-15) enhances and prolongs proliferation of primary cultured rat hepatocytes in the absence of serum.

Multiple rounds of cell division were induced in primary cultured rat hepatocytes in serum-free, modified L-15 medium supplemented with 20 mM NaHCO3 and 10 ng/ml EGF in a 5% CO2/95% air incubator. A 150% increase in cell number and DNA content was observed between day 1 and day 5. The time course of DNA synthesis of hepatocytes cultured in L-15 medium differed from that in DMEM/F12 medium in that there were four peaks of 3H-thymidine incorporation in the L-15 medium, at 60 h, 82 h, 96 h, and 120 h, but only one peak at 48 h in modified DMEM/F12 medium. Labeling studies of the hepatocytes indicated that more than 60% of the cells were stained with antibromodeoxyuridine (BrdU) antibody in the periods of 48-72 h and 72-96 h after plating at densities between 1.5 x 10(5) and 6.0 x 10(5) cells per 35-mm dish. Even at a density of 9.0 x 10(5) cells/dish, about 40% of the cell nuclei were stained with BrdU in the periods of 48-72 h and 72-96 h. In addition, about 20% of the hepatocytes in culture initiated a second round of the cell cycle between 48 and 96 h in culture. Proliferating cells, which were mononucleate with a little cytoplasm, appeared in small clusters or colonies in the culture from day 4. These proliferating cells produced albumin. The addition of essential amino acids to the DMEM/F12 medium enhanced the DNA synthesis of hepatocytes, thus indicating that the higher level of amino acids in L-15 medium may be an important factor in its enhanced ability to support the proliferation of primary cultured rat hepatocytes.

Effects of amino-acid composition of the medium and addition of fatty-acid derivatives on the induction of lipogenic enzymes in cultured hepatocytes

(1) Effects of essential and non-essential antino acids on induction of lipogenic enzymes were investigated in cultured rat heptocytes. Glucose-6-phosphate dehydrogenase was markedly induced by the addition of essential amino acids alone to the cultured medium, but was not induced by non-essential aniino acids. Fatty-acid synthetase was also markedly induced by a combination of both amino-acid types (more than by either type of amino acid alone). However, acetyl-CoA carboxylase and malic enzyme were slightly induced by the addition of essential and/or non-essential aniino acids. (2) When various kinds of fatty acids were individually added to the medium, the lipid-dependent decreases in lipogenic enzyme inductions were in the following order 18:2 > 20:4 > 18:1 > 16:0. When either linoleic acid, linoleoyl-CoA or trilinolein was added to the medium, linoleic acid was more effective as an inhibitor of the induction, without impairing the viability of cells.

Intravenous administration of essential amino acids to uremic patients on low protein diet.

Abstract. Patients with chronic renal disease and severe uremia (serum creatinine above 10 mg/100 ml) were treated in 1965‐67 with a restricted protein diet with addition of essential amino acids in tablet form, as described by Giovanetti and Maggiore. There were, however, often practical difficulties in carrying out an oral amino acid substitution. Parenteral administration of eight essential amino acids was introduced in 1968‐70 for 19 severely uremic patients once to twice a week for 1–14 months. The patients preferred parenteral administration of the essential amino acids, and few side‐effects were observed. Amino acid analysis of plasma showed all amino acid concentrations in the normal range in four severely uremic patients, who received a low protein diet (about 15 g/day) and 50 g essential amino acid/week. No signs of deficient protein synthesis were found. It is extremely difficult to calculate the optimum amino acid supply required by uremic patients. The fact that one of our patients had a life extension of 14 months indicates that the amino acid balance was reasonably adequate. In patients with a quickly developing renal deterioration the advantage of strict protein rationing is minimal. In the very slowly developing diseases there may be a gain of several months.

Nutrition of the bacon pig. XIX. The requirement of the bacon pig for certain essential amino acids

The addition of essential amino acids to all-vegetable diets, so as to raise the biological value of their proteins to the level of animal-protein concentrates, has often been advocated in the past by animal nutritionists. This aim was frustrated in practice since it was impossible, until recently, to secure the necessary supplies at prices that would make such additions economical. Feeding stuffs with added amino acids are now being sold commercially. This is possible following the manufacture of synthetic DL-methionine and crude L-lysine monochloride.It seemed desirable, therefore, to carry out investigations into the potential value of these amino acids to the pig feeder. This paper deals with the effect on growth, food utilization and retention of nitrogen of adding small amounts of lysine and methionine to the diet. An attempt is made to correlate the amino acid composition of the pig's diet with its rate of growth, the energy supply being adequate.