Mixture Of Non-essential Amino Acids Research Articles

Efficacy Of A Six Nonessential Amino Acid Mixture In Mitigating Knee Joint Conditions In Adults

Efficacy Of A Six Nonessential Amino Acid Mixture In Mitigating Knee Joint Conditions In Adults

P–283 Combination between amino acids profile of the spent culture media and morphokinetics parameters of human embryos to determine its viability

Abstract Study question How to determine human embryo viability noninvasively before embryo transfer? Summary answer We propose that the combination of the amino acid profile of an individual embryo with its morphokinetics will provide noninvasive tool to determine its viability. What is known already It was already known that human embryos at early cleavage require non-essential amino acids, while at the 8-cell to blastocyst stages, a mixture of non-essential and essential amino acids. Amino acids have important roles during embryo development. Acting as biosynthetic precursors,buffers of intracellular pH in the embryo, antioxidants, energy sources and regulators of metabolic function and signaling pathways. Many studies have used time-lapse to analyze human embryonic development including the process of fertilization and assessment of early events and introducednoninvasive prognostic markers which predict embryo development and correlate it to IVF treatment outcomes. Study design, size, duration This study was a prospective cohort study approved by the Clinical Trial Ethical Committee of Faculty of Medicine, Alexandria University according to ethical standards of scientific research (Serial number: 0303721).Thirty females aged 30.13 ± 4.83 years undergoing ICSI cycle in the Madina Fertility Center, during the period of March 2018 to November 2019.202 MII oocytes were incubated individually in embryoscope. Participants/materials, setting, methods Embryos (n = 161) were divided on Day 5 into two groups –developed embryos “Group D” (embryos that developed to blastocyst) and arrested embryos “Group A” (embryos remain at cleavage stage and fail to develop to blastocys).Developed embryos (Group D) included 99 embryos, and Arrested embryos (Group A) included 62 embryos. For each group, morphokinetic developmental points using embryoscope and the different amino acids concentrations in spent culture medium were analyzed using LC- mass spectro etry. Main results and the role of chance On one hand, the first appearance of pronuclei (TPNa), t2, t4 and CC2 in group D occurred significantly earlier than those of Group A.Analysis of 19 essential and non-essential amino acids in spent culture medium of each embryo in the two studied groups D and A showed a significantly higher concentration of two essential amino acids L-Valine (145.73 ± 150.96) and L-Phenylalanine (61.59 ± 55.78) in Group D than their concentration in Group A ( 104.58 ± 33.58, 44.24 ± 14.61, respectively , p ≤ 0.05).and significantly lower concentration of three non-essential amino acids L-Tyrosine (62.56 ± 41.03) , L-Cysteine (19.48 ± 11.90), and L-Alanine (136.0 ± 389.83) observed in Group D when compared to Group A (69.57 ± 20.78, 22.37 ± 8.59,145.33 ± 165.22, respectively, Limitations, reasons for caution It is important to note, that results were developed on a data set from one clinic with different stimulation protocols, a multicenter data and a correlation with the stimulation protocol used should be involved in future studies, in addition a larger sample size to avoid high standard deviation is recommended Wider implications of the findings: We can conclude that amino acid turnover is independent of the traditional morphological assessment of embryos and it may reflect its viability. The prospective combined use of amino acids profile of individual embryo and its morphokinetic parameters may contribute to introduce a new noninvasivs tool that may improve implantation rate Trial registration number 0303721

Dietary lysine requirement of juvenile Silver pompano, Trachinotus blochii (Lacepede, 1801)

A 12-week feeding trial was conducted to quantify the dietary lysine requirement of juvenile silver pompano with an initial average weight of 6.28 g reared in indoor recirculatory system. Six treatment diets were designed with isonitrogenous, isolipidic and isoenergetic diets. (42% CP, 6% CL and 4.28 kcal g−1 GE) were formulated with graded levels of lysine (1.52, 1.85, 2.21, 2.49, 2.74 and 2.98 g/100 g, dry diet). Equal amino acid nitrogen was maintained by replacing lysine with nonessential amino acid mixture. Fish were randomly stocked, in triplicate groups, in 180 L indoor glass rectangular tanks with recirculatory system and fed to apparent satiation over two feedings at 10:00 and 16:00 h daily during the experimental period. The results indicated that there were significant differences in growth and feed utilization among the treatments. Fish fed diets with lysine in different treatments showed high survival rate (95–100%). Maximum weight gain (WG), specific growth rate (SGR) and protein efficiency ratio (PER) occurred at 2.21% dietary lysine. The hepatosomatic index (HSI), viscerosomatic index (VSI) and crude protein content in whole body were significantly affected by dietary lysine levels. There were significant differences (P < .05) in total serum protein levels and erythrocyte count in fish fed diets with different dietary lysine levels. No significant differences were observed in the levels of serum glucose, triglycerides and creatinine levels among the treatments. In the present study, optimization of fitted quadratic regression of weight gain%, SGR, PER and FER on lysine in diet revealed that the optimum lysine requirement of silver pompano was in the range of 2.40–2.45% of dry diet (5.71–5.83% of dietary crude protein). Statement of relevanceFirst report of lysine requirement of juvenile silver pompano.

Effects of dietary essential amino acid deficiencies on the growth performance and humoral immune response in silvery-black porgy (Sparidentex hasta) juveniles

A 6-week feeding trial was conducted for determining the effects of dietary essential amino acids (EAA) deficiencies on growth performance and non-specific immune responses in silvery-black porgy juveniles (4.7 ± 0.1 g initial weight). Eleven isoproteic (ca. 47%) diets were formulated including a control diet containing the optimum quantity of EAA, and ten EAA-deficient diets. All diets contained 36% fish meal and 18.5% crystalline EAA and non-essential amino acids (NEAA) as the main source of dietary proteins. All the EAA and NEAA incorporated in the crystalline amino acids mixture of the control diet simulated the amino acids profile of the fish meal. The other 10 EAA-deficient diets were formulated by the deletion of each of the 10 EAA (crystalline form) from the control diet and replaced by a mixture of NEAA for the adjustment of dietary nitrogen contents. At the end of the experiment, fish fed with threonine-deficient diet showed the lowest survival rate (p < .05), whereas growth performance decreased in fish fed all EAA-deficient diets, although the reduction in body growth varied depending on the EAA considered. Plasma total protein decreased in all experimental groups except for fish fed the phenylalanine-deficient diet. Fish fed with arginine- and lysine-deficient diets had the lowest plasma C3, C4, lysozyme, total immunoglobulin and total superoxide dismutase activity (p < .05). Present results indicated that lysine, methionine and threonine were the most limiting EAA in terms of growth performance; however, arginine, threonine and lysine were the most limiting EAA for innate immunity responses in silvery-black porgy juveniles.

Establishing the optimum dietary essential amino acid pattern for silvery-black porgy (Sparidentex hasta) juveniles by deletion method

A 6-week feeding trial was conducted to estimate the optimum dietary essential amino acid (EAA) pattern for silvery-black porgy juvenile based on the AA deletion method. Eleven isonitrogenous and isoenergetic diets were formulated containing 60% of fish meal nitrogen and 40% of crystalline AA nitrogen. In the control diet, the EAA profile was made similar to fish meal protein. Ten other diets were formulated similar to the control diet but replacing 40% of each EAA by a mixture of non-essential amino acids. Triplicate groups of fish (initial body weight of 4.7 g) were handfed with the experimental diets, three times a day, to visual satiation, for 42 days. At the end of the trial, final body weight of all EAA-deficient groups was lower than that of control group, ranging from 6.3% of reduction with arginine-deficient diet to 39.4% of reduction with lysine-deficient diet, relatively to the control group. Based on the relationship between nitrogen retention and EAA intake of the control and EAA-deficient diets, the optimal dietary EAA profile for silvery-black porgy juveniles was estimated to be (g 16/g N): arginine 5.3, lysine 6.0, threonine 5.2, histidine 2.5, isoleucine 4.6, leucine 5.4, methionine + cysteine 4.0 (in a diet containing 0.6 cysteine), phenylalanine + tyrosine 5.6 (in a diet containing 1.9 tyrosine), tryptophan 1.0 and valine 4.6.

Commentary: Rheumatoid Cachexia Revisited: A Metabolic Co-morbidity in Rheumatoid Arthritis.

The “mini review” by Masuko (1) contains a quite extensive summary of “rheumatoid cachexia” (2) [i.e., loss of muscle mass in rheumatoid arthritis (RA)], an often overlooked and misdiagnosed co-morbidity. Masuko looks at the definition of “rheumatoid cachexia,” as well as the pathogenesis of the condition referring to the key role of pro-inflammatory cytokines. Interestingly, various strategic therapy options designed to attenuate rheumatoid cachexia by disease-modifying anti-rheumatic drugs (DMARDS), anti-cytokine therapies, and exercise training (i.e., resistance and endurance) are covered. However, what the review fails to mention or expand upon, is the relative ineffectiveness of exercise on “rheumatoid cachexia” once supervision is withdraw. The review also neglects to discuss (despite referencing a relevant trial) another potential key tool in the armory against “rheumatoid cachexia”: nutritional supplementation. This commentary will confine itself to briefly recounting some of these. As Masuko states that resistance training is the most beneficial means to increase both lean mass and physical function in RA. Both Marcora et al. (3) and Lemmey et al. (4) showed that progressive resistance training (PRT) for a period of 12 and 24 weeks (exercising two and three times per week, respectively) was able to attenuate the effects of rheumatoid cachexia, specifically increasing lean mass, strength, and physical function in patients with RA. However, a follow-up study for 3 years later by Lemmey et al. (5) found that once supervision was withdrawn, no subjects from the original study (4) were performing relevant PRT or any other form of regular high intense exercise and, as a result, lean mass had regressed to baseline levels, as had much of the trunk fat mass and body fat percentage. Lack of adherence to high-intense exercise in RA has been demonstrated by others (6). Unfortunately, it seems habitually performed, high-intensity exercise (i.e., PRT) is unlikely to be widely adopted as a general treatment strategy for reversing “rheumatoid cachexia” and restoring function, then the challenge to develop a treatment option that is easily administered, inexpensive, and makes limited demands of the patient remains. Anabolic nutritional supplementation offers a potential treatment option that is easily administered, inexpensive, and makes limited demands of the patient. Scientific evidence continues to suggest that nutrition should be part of routine care in those with muscle wasting disorders [for review, see Stamp et al. (7)]. Specifically, up to 75% of RA patients believe that food and nutrition play an important role in their symptom severity, with 50% of RA patients reportedly trying some form of dietary manipulation in an attempt to attenuate symptomology (7). Marcora et al. (8) previously investigated the effects of daily 12 weeks of a mixture of β-hydroxy-β-methylbutyrate, glutamine, and arginine (HMB/GLN/ARG) protein supplementation in 40 RA patients. The results showed that both HMB/GLN/ARG and a control mixture of other non-essential amino acids (alanine, glutamic acid, glycine, and serine) were both equally effective in increasing lean mass (~0.4 kg) and improving some measures of physical function and strength. Creatine monohydrate, a combination of essential amino acids, has generally been shown to be more effective in increasing lean mass and physical performance than other protein-based supplements, including HMB/GLN/ARG [for review, see Nissen (9)]. In the only study investigating the use of creatine in RA, Willer et al. (10) found that creatine supplementation increased muscle strength in 8 out of the 12 patients by an average of 14% as determined by the muscle strength index, although this increase in strength was not actually associated with changes of creatine (or phosphocreatine) levels in the muscle. Nonetheless, creatine has been shown to be effective, without additional exercise training, in range of clinical populations, including muscular dystrophy patients and the elderly who, like RA patients, present with reduced muscle mass and impaired physical function [for review, see Wilkinson et al. (11)]. Evidently, more research is needed, and as such we have just completed a randomized control trial investigating the effects of creatine in RA patients (manuscript in preparation). To summarize, although PRT exercise is arguably the most effective way to attenuate the effects of rheumatoid cachexia, due to its high-intense nature, it is unlikely to be widely adopted as a general treatment strategy. Nutritional supplementation, specifically those that focus on muscle anabolism may be a viable option. Alongside, HMB/GLN/ARG protein supplementation, creatine monohydrate may be a potential therapeutic option in RA, as it has been effective in range of clinical and elderly populations.

Dietary methionine requirement of juvenilePseudobagrus ussuriensis

An 8-week feeding trial was conducted to determine the optimum dietary methionine (Met) requirement of juvenile Pseudobagrus ussuriensis with an initial average weight of 0.60 g reared in indoor flow-through and aerated aquaria. Six isonitrogenous (430 g kg−1 protein) and isolipidic (50 g kg−1 lipid) test diets were formulated to contain graded levels of crystalline L-methionine (4.9, 9.0, 11.8, 14.2, 18.1 and 20.8 g kg−1 dry diets, respectively) at a constant dietary cystine level of 2.5 g kg−1 dry diets. Equal amino acid nitrogen was maintained by replacing methionine with non-essential amino acid mixture. Fish were randomly allotted to 18 aquaria (1.0 × 0.5 × 0.8 m) with 50 fish to each glass aquarium. Fish were fed twice daily (08:00 and 16:00) to apparent satiation. No significant difference was observed in survival of fish (84.67–91.33%). Specific growth rate (SGR), weight gain (WG), feed conversion ratio (FCR), protein productive value (PPV) and protein efficiency ratio (PER) were significantly affected by different dietary methionine levels (P < 0.05). WG, SGR PPV and PER increased, while FCR decreased with increasing dietary methionine level from 4.9 to 11.8 g kg−1 (P < 0.05). However, with further increase from 11.8 to 20.8 g kg−1, WG, SGR PPV and PER significantly decreased, FCR increased (P < 0.05). The whole body and muscle composition were affected by different dietary methionine levels (P < 0.05). Condition factor (CF) increased with increasing dietary methionine levels up to 11.8 g kg−1 (P < 0.05) and after 11.8 g kg−1 methionine diet, but not significant, declines were observed (P > 0.05). Hepatosomatic index (HSI) of the 4.9, 9.0, 11.8 and 14.2 g kg−1 Met diets was significantly higher than that of fish fed diets 18.1 and 20.8 g kg−1 Met diets (P < 0.05). Viscerosomatic index (VSI) of the 4.9, 9.0 and 11.8 g kg−1 Met diets was significantly higher than that of fish fed diets 14.2, 18.1 and 20.8 g kg−1 Met diets (P < 0.05). Quadratic regression analysis of WG and PER against dietary methionine levels indicated that the optimal dietary methionine requirement for maximum growth and feed utilization of juvenile Pseudobagrus ussuriensis was 14.3 and 14.1 g kg−1 dry diet (35.3 and 34.8 g kg−1 dietary protein), respectively, in the presence of 2.5 g kg−1 dry diets cystine.

Citrulline stimulates muscle protein synthesis in the post-absorptive state in healthy people fed a low-protein diet – A pilot study

Amino acid (AA) availability is critical to maintain protein homeostasis and reduced protein intake causes a decline in protein synthesis. Citrulline, an amino acid metabolite, has been reported to stimulate muscle protein synthesis in malnourished rats. To determine whether citrulline stimulates muscle protein synthesis in healthy adults while on a low-protein diet, we studied 8 healthy participants twice in a cross-over study design. Following a 3-days of low-protein intake, either citrulline or a non-essential AA mixture (NEAA) was given orally as small boluses over the course of 8 h. [ring-(13)C6] phenylalanine and [(15)N] tyrosine were administered as tracers to assess protein metabolism. Fractional synthesis rates (FSR) of muscle proteins were measured using phenylalanine enrichment in muscle tissue fluid as the precursor pool. FSR of mixed muscle protein was higher during the administration of citrulline than during NEAA (NEAA: 0.049 ± 0.005; citrulline: 0.060 ± 0.006; P = 0.03), while muscle mitochondrial protein FSR and whole-body protein turnover were not different between the studies. Citrulline administration increased arginine and ornithine plasma concentrations without any effect on glucose, insulin, C-peptide, and IGF-1 levels. Citrulline administration did not promote mitochondria protein synthesis, transcripts, or citrate synthesis. Citrulline ingestion enhances mixed muscle protein synthesis in healthy participants on 3-day low-protein intake. This anabolic action of citrulline appears to be independent of insulin action and may offer potential clinical application in conditions involving low amino acid intake.

Metabolic reprogramming by KSHV in cellular transformation

Oncogenic Kaposi’s sarcoma-associated herpesvirus (KSHV) is causally linked to several human cancers including Kaposi’s sarcoma and primary effusion lymphoma. Despite intensive studies, little is known about how KSHV alters cellular metabolism during cellular transformation. Using a novel model of KSHV-induced cellular transformation of primary rat embryonic metanephric mesenchymal stem cells (MM), we found that KSHV-transformed MM (KMM) cells did not require glucose for growth and formation of colonies in soft agar. Consistent with these results, KMM cells had lower levels of glucose consumption, lactate production, oxygen consumption and intracellular ATP levels. Compared to MM cells, KMM cells had lower levels of glucose transporters GLUT1 and GLUT3. Genetic deletion of KSHV-encoded microRNA cluster or vFLIP gene from the viral genome, which resulted in reduced NF-κB activity, significantly increased glucose consumption and lactate production, and sensitized the cells to glucose deprivation. Accordingly, inhibition of the NF-κB pathway with either RelA siRNAs or inhibitor JSH-23 dramatically increased glucose consumption and lactate production. Thus, the insensitivity of KMM cells to glucose is mediated by the heightened NF-κB activity. In contrast to the insensitivity to glucose, KMM cells were sensitive to glutamine deprivation. Glucose deprivation further increased glutamine consumption of KMM cells. Inhibition of glutamine metabolism with amino oxyacetate (AOA), an inhibitor of glutamate-dependent transaminases, or epigallocatechin gallate (EGCG), an inhibitor of glutamate dehydrogenase (GDH) mimicked the effect of glutamine deprivation and effectively suppressed cell growth and formation of colonies in soft agar. Addition of nonessential amino acid (NEAA) mixture or asparagine alone was sufficient to restore the growth of KMM cells upon glutamine deprivation while dimethyl α-ketoglutarate only had partial effect, indicating that glutamine not only provided a carbon source to fuel the tricarboxylic acid (TCA) cycle but also supplied nitrogen for biosynthesis. Taken together, these results indicate that KMM cells depend neither on aerobic glycolysis nor on oxidative phosphorylation but instead on glutamine to support cell growth and transformation. Our findings also suggest that metabolic reprogramming might have a critical role in KSHV-induced cellular transformation.

Development of primary cell cultures from mud crab, Scylla serrata, and their potential as an in vitro model for the replication of white spot syndrome virus

Primary cell cultures were developed from haemocytes and testis of Scylla serrata. Haemocytes were collected from live animals and cultured in double-strength L-15 medium (2× L-15) prepared in crab saline, supplemented with 5% foetal bovine serum and antibiotic-antimycotic solution (penicillin 100U/mL, streptomycin 100μg/mL and amphotericin B 0.25μg/mL) with osmolality adjusted to 894mOsm/kg. The haemocytes adhered within 2h after seeding and showed proliferation up to 72h. The disaggregated testis tissue fragments were seeded in 3× L-15 supplemented with non-essential amino acid mixture, lipid concentrate and antibiotic-antimycotic solution, with osmolality adjusted to 1,035mOsm/kg with crab saline. Cells from the testis could be subcultured and maintained up to 21d as suspension culture. Different dilutions of white spot syndrome virus (WSSV) inoculum (known virus copy number) prepared from infected Penaeus monodon were inoculated in the cultured cells, and the cytopathic effects like detachment, rounding of cells and clear areas of depleted cells were observed after 48h in haemocyte cultures. However, WSSV-exposed testis cells did not show any obvious change until 72h post-infection. WSSV was detected in both haemocyte and testis cultures at different time-points of infection by conventional and real-time PCR using WSSV-specific primers. The transcripts of WSSV were found to be much higher in haemocytes than in testis culture. The virus harvested from the cultured haemocytes after three passages could infect healthy P. monodon. The present study showed that mud crab haemocyte culture can support WSSV replication, and it can be used as an in vitro tool for WSSV replication.

Dietary threonine requirements of juvenile Pacific white shrimp, Litopenaeus vannamei

An 8-week feeding trial was conducted to determine the dietary threonine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei. Six isonitrogenous and isolipidic practical diets (43% crude protein and 7.5% crude lipid) were formulated to contain graded dietary threonine levels ranging from 1.07% to 2.30% (dry weight). In all of the diets, the nitrogen content of the amino acids was kept the same by replacing threonine with a non-essential amino acid mixture. Each diet was randomly assigned to triplicate groups of 40 juvenile shrimp (approximately 0.53g) that were fed 4 times daily to apparent satiation. The results indicated that significant difference was observed in the weight gain among all treatments. Maximum weight gain was obtained at 1.67% dietary threonine; however, weight gain did not significantly increase with further dietary threonine increases. The survival of the shrimps showed no significant differences among all treatments. Feed efficiency, protein efficiency ratio and protein productive value were also significantly influenced by the dietary threonine levels, and the trends were similar to those of growth performance. There were no significant differences among dry matter, crude protein, crude lipid or ash content in the whole body and muscle composition. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), superoxide dismutase (SOD) and phenoloxidase (PO) activities in hemolymph were significantly affected by dietary threonine levels. Shrimp fed the diet containing 2.30% threonine had higher AST and ALT values than those fed the other diets; however, the highest SOD and PO activities were observed at 2.05% dietary threonine. The optimal dietary threonine requirement, estimated by a broken-line model based on SGR, was 1.51% of the dry diet (corresponding to 3.53% of dietary protein on a dry-weight basis). Considering the threonine leaching loss in seawater within 30min (duration of feeding each time), the threonine requirement for L. vannamei is 1.18% of dry diet (2.81% of the dietary protein).

Dietary arginine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei

An 8-week feeding trial was conducted to evaluate the dietary arginine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei. Six isonitrogenous and isolipidic practical diets (41% crude protein and 7.5% crude lipid) were formulated to contain graded dietary arginine levels ranging from 1.44 to 2.74% (dry weight) in approximately 0.3% increments. In all of the diets, the nitrogen content of the amino acids was kept the same by replacing arginine with a non-essential amino acid mixture. Each diet was randomly assigned to triplicated groups of 40 juvenile shrimp (approximately 0.50g) 4 times daily to apparent satiation. The results indicated that the specific growth rate and weight gain were significantly influenced by the dietary arginine levels. Maximal specific growth rate and weight gain occurred at 2.32% dietary arginine; however, specific growth rate and weight gain did not significantly increase with further increases in dietary arginine from 2.51% to 2.74%. Feed efficiency, protein efficiency ratio and protein productive value were also significantly affected by the dietary arginine levels, and the trends were similar to those of growth performance. No mortality was observed among all treatments. There were no significant differences among crude protein, crude lipid and ash content in the whole body and muscle composition. The total protein in hemolymph was significantly affected by dietary arginine levels, however, there were no significant differences in urea nitrogen, triglycerides and cholesterol in the hemolymph among all treatments. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), superoxide dismutase (SOD), arginase and nitric oxide synthase (NO) activities in the hemolymph were significantly affected by dietary arginine levels. The optimal dietary arginine requirement estimated by two slope broken-line model based on SGR was 2.32% of the dry diet (corresponding to 5.66% of dietary protein on a dry weight basis). Considering the arginine leaching loss in seawater within 30min (duration of feeding each time), the arginine requirement for L. vannamei is 1.96% of dry diet (4.77% of the dietary protein).

Dietary lysine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei

An 8-week feeding trial was conducted to estimate the dietary lysine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei. Six isonitrogenous and isolipidic practical diets (40% CP and 7.5% lipid) containing graded dietary lysine levels ranged from 1.44 to 2.49% (dry weight) at about 0.3% increments were formulated. Equal amino acid nitrogen was maintained by replacing lysine with nonessential amino acid mixture. Triplicate groups of 40 juvenile shrimps (about 0.52g initial weight) were fed one of the diets four times daily to apparent satiation. No significant differences were observed in survival rates of shrimps (97.50–100%, P>0.05), but specific growth rate (SGR), weight gain (WG), feed efficiency, protein efficiency ratio and protein deposition ratio were significantly affected by different dietary lysine levels (P<0.05). There were no significant differences in whole body and muscle composition (crude lipid, crude protein and ash), except for the crude protein content of whole body. Urea nitrogen, total protein and the activity of SOD in hemolymph showed no significant differences (P>0.05). Triglyceride, Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT) in hemolymph were significantly affected by dietary lysine levels (P<0.05). The optimal dietary lysine requirement estimated by broken-line model based on SGR was 2.05% of dry diet (4.93% dietary protein). Considering the lysine leaching loss in seawater within 30min (duration of feeding each time), the lysine requirement for L. vannamei is 1.64% of dry diet (3.95% of the dietary protein).

Dietary arginine requirement of juvenile yellow grouper Epinephelus awoara

An 8-week feeding trial was conducted to determine the dietary arginine requirement of juvenile yellow grouper Epinephelus awoara. Six isonitrogenous and isolipidic diets (43% crude protein and 10% lipid) were formulated to contain six graded dietary arginine levels ranging from 2.01 to 3.27% (dry weight) in about 0.3% increments. In all diets, amino acid nitrogen contents were kept the same by replacing arginine with a non-essential amino acid mixture. Each diet was randomly assigned to triplicated groups of 20 juvenile fish (about 4.23g) twice daily to apparent satiation. The results indicated that the specific growth rate and weight gain at different dietary arginine levels were all significantly different. Maximal weight gain and specific growth rate occurred at 2.83% dietary arginine, however, weight gain and specific growth rate did not significantly increase with further increase in dietary arginine from 2.83% to 3.27%. Feed efficiency and protein efficiency ratio were not significantly affected by the dietary arginine levels. No mortality was observed at any diets. The dietary arginine levels significantly affected condition factor and hepatosomatic index, however, viscerosomatic index and muscle ratio were not significantly influenced by the dietary arginine levels. Crude protein, crude lipid and ash content in the muscle and dry matter in the whole body were significantly affected by the dietary arginine levels; fish fed with the 2.83% arginine diet had a higher crude protein content than fish fed with the other diets. There were no significant differences in red blood cell count, hemoglobin content and hematocrit among all treatments. Total nitric oxide synthase, inducible nitric oxide synthase in liver, and total nitric oxide synthase in plasma were significantly influenced by the dietary arginine levels. The essential amino acid concentrations in the muscle were significantly affected by the dietary arginine levels; however, there was no significant difference in essential amino acid concentrations in the liver. Quadratic regression analysis on specific growth rate and weight gain against dietary arginine levels indicated that the optimal dietary arginine requirement was estimated to be 2.8% of the diet (corresponding to 6.5% of dietary protein on a dry weight basis).

Metabolic and Clinical Effects of the Supplementation of a Functional Mixture of Amino Acids in Cerebral Hemorrhage

Oral supplementation of a specific mixture of essential and non-essential amino acids has been shown to modulate hypercatabolism in patients with chronic heart failure, leading to improved clinical outcome. The aim of this study was to test whether such effects could be replicated in an acute clinical model of hypercatabolism. After approval by the Ethics Committee, patients with acute brain hemorrhage admitted to the Neurosurgical ICU were randomly assigned to receive enterally for 14 days 20% of their estimated nitrogen requirements as a standard protein supplement (control group; n = 9) or as a functional amino acid mixture (Aminotrofic®, Errekappa Euroterapici; study group; n = 10). Metabolic and clinical outcome measures were monitored. In the study group, insulin sensitivity and total lymphocyte count appeared to improve when compared with control patients. Less positive blood cultures were found in the study group against control patients (4 vs. 7, respectively; P = 0.05). Also, mortality in the study group was reduced than in control patients (60 vs. 77%; P = n.s.). Supplementation with specific amino acids in critically ill patients may modulate metabolic response and improve clinical outcome.

Nuclear Factor κB- and Specificity Protein 1-dependent p53-mediated Bi-directional Regulation of the Human Manganese Superoxide Dismutase Gene

Tumor suppressor p53 is known to activate certain sets of genes while suppressing others. However, whether p53 can both activate and suppress the same gene is unclear. To address this question, concentration-dependent p53 effect on the manganese superoxide dismutase (MnSOD) gene was investigated. By transfecting p53 in PC-3 cells, we demonstrate that low concentrations of p53 increase while high concentrations suppress MnSOD expression. The physiological relevance of this effect was determined in vitro and in vivo using combined UVB-mediated activation and small interference RNA-mediated suppression of p53. Results were consistent with the bi-directional effect of p53 on MnSOD expression. MnSOD-promoter/enhancer analysis demonstrates that p53 is suppressive to the promoter activity regardless of the presence or absence of putative p53 binding sites. However, a low level of p53 increases MnSOD gene transcription in the presence of the intronic-enhancer element, and this effect is dependent on nuclear-factor kappaB (NF-kappaB) binding sites. Expression of p53 enhances nuclear levels of p65 with corresponding increase in the DNA-binding activity of NF-kappaB as detected by electrophoretic mobility shift and chromatin immunoprecipitation assays. Transfection of p65 small interference RNA reduces the positive effect of p53 on MnSOD gene transcription. These data suggest that p65 can overcome the negative effect of p53 on MnSOD expression. However, when the level of p53 was further increased, the suppressive effect of p53 outweighed the positive effect of p65 and led to the suppression of MnSOD gene transcription. These results demonstrated that p53 can both suppress and induce MnSOD expression depending on the balance of promoter and enhancer binding transcription factors.

Effect of essential and non-essential amino acid addition to a nitrogen-free diet on endogenous ileal amino acid flow in growing pigs

Pigs fitted with ileal T-cannula in the terminal ileum were used to study the effect of synthetic amino acids (AA) added to a nitrogen-free diet on endogenous losses. We compared the obtained data with data from other research centres in the world that are focusing on these problems. In the present experiment, we used three synthetic diets – a nitrogen-free (NF) diet, a diet with added essential AA (E), a diet with the same amounts of essential AA and a mixture of non-essential AA (E+N) added. The diets, apart from the amount of AA, had the same composition. Chromium oxide was used as an indigestible marker. The supplementation of the NF diet with sulphur AA, threonine and tryptophan resulted in a reduction of the endogenous flow of all AA except for cysteine. However, the difference between the NF and E diet was significant only in the case of proline. The effect of the non-essential AA addition to diet E was negligible, even though the endogenous flow of most AA tended to decrease. In comparison with NF diet, the endogenous flow of total N in diets E and E+N was reduced by about 30%. This reduction was mainly due to the decreased endogenous flow of proline, which accounted for 59% in diet E and 55% in diet E+N. Proline was the most abundant AA in all diets, followed by glycine and glutamic acid. The sum of proline and glycine in diets NF, E and E+N amounted to 59, 44, and 46% of total AA flow, respectively. In contrast, the proportion of the sum of essential AA of total AA flow in diets NF, E and E+N was 21, 28 and 27%, respectively. Our data on the endogenous AA and N flow are in the range of previously published values.

The optimum dietary essential amino acid profile for gilthead seabream ( Sparus aurata) juveniles

A study was undertaken to establish the optimum dietary essential amino acid (EAA) profile for gilthead seabream juveniles based on the amino acid (AA) deletion method. For that purpose 11 diets were formulated to be isonitrogenous (6.72% N) and isolipidic (18%). In the control diet half of the nitrogen was provided by protein bound-AAs (fish meal) and the other half by a mixture of crystalline L-AAs. The overall AA profile of this diet was made similar to that of fish meal protein. Ten other diets were formulated identical to the control except for the deletion of 45% of a single EAA in each diet and by adjusting the nitrogen level with a non-essential AA mixture. Each diet was assigned to four groups of 22 fish (initial body weight of 4.6 g) and the trial lasted 43 days at a water temperature of 25 °C. Fish were fed by hand, twice daily, using a pair-feeding scheme. At the end of the trial the relationship between nitrogen gain and AA intake of the test and control diets was determined. Based on these data, and assuming that nitrogen retention responds linearly to dietary EAA content when a given AA is limiting, the quantity of each EAA that can be removed from the control diet without affecting nitrogen retention was computed and the ideal dietary EAA profile for gilthead seabream juveniles was estimated. Expressed relative to lysine (= 100) A/E ratios were estimated to be: arginine, 108.3; threonine, 58.1; histidine, 36.8; isoleucine, 49.7; leucine, 92.7; methionine, 50.8; phenylalanine + tyrosine, 112.3; valine, 62.6; and tryptophan, 14.6. This EAA profile correlates tightly to the whole-body EAA composition of gilthead seabream ( R 2 = 0.99; p > 0.001).

Dietary Glutamine Supplementation Increases the Activity of Peritoneal Macrophages and Hemopoiesis in Early-Weaned Mice Inoculated with Mycobacteriumbovis Bacillus Calmette-Guérin

Infants who are breast-fed have been shown to have a lower incidence of certain infectious diseases compared with formula-fed infants. Glutamine is one of the most abundant amino acids found in maternal milk and it is essential for the function of immune system cells such as macrophages. The purpose of this study was to investigate the effect of glutamine supplementation on the function of peritoneal macrophages and on hemopoiesis in early-weaned mice inoculated with Mycobacterium bovis bacillus Calmette-Guérin (BCG). Mice were weaned at 14 d of age and distributed to 2 groups and fed either a glutamine-free diet (n = 16) or a glutamine-supplemented diet (+Gln) (n = 16). Both diets were isonitrogenous (with addition of a mixture of nonessential amino acids) and isocaloric. At d 21, 2 subgroups of mice (n = 16) were intraperitoneally injected with BCG and all mice were killed at d 28. Plasma, muscle and liver glutamine concentrations and muscle glutamine synthetase activity were not affected by diet or inoculation with BCG. The +Gln diet led to increased leukocyte and lymphocyte counts in the peripheral blood (P < 0.05) and granulocyte and lymphocyte counts in the bone marrow and spleen (P < 0.05). The +Gln diet increased spreading and adhesion capacities, hydrogen peroxide, nitric oxide, and tumor necrosis factor-α (TNF α) syntheses and the phagocytic and fungicidal activity of peritoneal macrophages (P < 0.05). The interaction between the +Gln diet and BCG inoculation increased the area under the curve of interleukin (IL)-1 β and TNF α syntheses (P < 0.05). In conclusion, the intake of glutamine increases the function of peritoneal macrophages and hemopoiesis in early-weaned and BCG-inoculated mice. These data have important implications for the design of breast milk substitutes for human infants.

Dietary lysine requirement of juvenile cobia (Rachycentron canadum)

An 8-week feeding trial was conducted to quantify the dietary lysine requirement of juvenile cobia with an initial average weight of 1.25 g reared in indoor flow-through and aerated aquaria. Six isonitrogenous and isoenergetic practical diets (44% CP and 16% lipid) containing six levels of dietary lysine ranging from 1.15 to 3.25% (dry weight) at about 0.4% increments, using fish meal and wheat gluten as sources of intact protein, supplemented with crystalline amino acids. Equal amino acid nitrogen was maintained by replacing lysine with nonessential amino acid mixture. Each diet was randomly assigned to three aquaria and was fed to apparent satiation by hand four times daily. The results indicated that there were significantly differences in growth performance and feed utilization among the treatments. Maximum weight gain, special growth rate and protein efficiency ratio occurred at 2.38% dietary lysine; but with the increase of dietary lysine from 2.38 to 3.25%, weight gain, special growth rate and protein efficiency ratio did not significantly increase. The hepatosomatic index, viscerosomatic index, condition factor, crude protein content in whole body and main composition in muscle were significantly affected by dietary lysine levels; however moisture, lipid and ash content in whole body were not significantly affected by the dietary lysine. There were significant differences in total serum protein, glucose and triacyglycerol concentrations in fish fed diets with different dietary lysine levels. Haematocrit and leukocyte count were significantly affected by dietary lysine level, but hemoglobin and red blood cell count were not significantly affected. Lysine concentration in serum was significantly increased with the increase of dietary lysine level from 1.15 to 2.38%. Broken-line analysis on the basis of special growth rate showed that the dietary lysine requirement of juvenile cobia was 2.33% of dry diet (5.30% dietary protein).