Non-essential Amino Acids Research Articles

Abstract Mo109: Importance of Myocyte Serine De Novo Biosynthesis and its Downregulation in Heart Failure

Introduction: The failing heart exhibits metabolic inflexibility and dysregulated metabolism. Serine is a non-essential amino acid that contributes to purine synthesis, redox, and amino acid synthesis. It is transported into cells from the circulation or formed by de novo synthesis (SdS). We have found human failing myocardium has reduced serine (Circ 2023;147:1147) and lower expression of SdS genes (Circ 2021;143:120). Yet, little is known about the role of SdS or its depression in myocardium. Hypothesis: Reduced serine biosynthesis impairs myocyte energy and redox balance that could contribute to heart failure. Methods/Results: Immunoblots of human HF myocardium found phosphoglycerate dihydrogen-ase (PHGDH, rate limiting SdS enzyme) and other SdS enzymes were reduced in HF, and moreso in HF with preserved ejection fraction. Expression of plasmalemmal serine transporters SLC1A4, SLC1A5, SLC12A4 were consistently depressed in HFpEF. To assess the relative contribution of exogenous serine versus SdS, we inhibited PHGDH by siRNA or an inhibitor (NCT503). The former reduced serine by 71% despite exogenous sources, and both induced greater cytotoxicity than from solely depleting exogenous sources. Inhibiting PHGDH in serine/glycine-free media induced cytotoxicity after 1hr, whereas with exogenous serine, this occurred by 24 hours. 24 hr PHGDH knockdown reduced ATP and GTP levels, mitochondrial DNA. In response to endothelin-1 stimulation, basal and maximal mitochondrial O 2 consumption increased along with PHGDH gene expression. These changes in mitochondrial respiration were essentially prevented by gene silencing of PHDGH coupled to a decline in TCA metabolites. PHGDH inhibition also increased oxidative stress (increased GSSG/GSH) and reduced NAD levels. The cytotoxicity induced by 24 hr SdS inhibition by PHGDH knockdown could be offset by supplementing myocytes with ribose (purine precursor) and DTT (antioxidant). Conclusion: This study identifies SdS as a pivotal metabolic pathway in myocyte energy metabolism homeostasis, and its depression may play a role in HF, particularly HFpEF. These results support enhancing serine metabolic pathways as a therapeutic strategy for these diseases.

Effects of GH L127V and TG5 C422T polymorphisms on the hormonal profile, slaughter traits, and meat quality of Hereford bulls.

The creation of objective methods for the evaluation and improvement of quantitative and qualitative indicators of meat productivity in farm animals should be based on a comprehensive analysis of the genetic, physiological, and biochemical parameters of the animal. This study aimed to investigate the effects of growth hormone (GH) and thyroglobulin (TG5) gene polymorphisms on the hormonal status, slaughter traits, and chemical, amino acid, and fatty acid composition of meat in Hereford bulls. Hereford bulls (n = 9) were reared under the same feeding and housing conditions until the age of 21 months, after which they were slaughtered. Polymerase chain reaction-restriction fragment length polymorphism was performed for genotyping GH L127V and TG5 C422T polymorphisms. The experimental animals were evaluated to determine slaughter traits (including pre-slaughter weight, carcass, and internal fat weight and yield), chemical, fatty acid, and amino acid composition of ground beef, and hormonal status using serum concentrations of GH, triiodothyronine, and thyroxine. Animals with the valine homozygous (VV) genotype of GH had the maximum serum GH level of 9.33 mIU/mL (p = 0.10) higher than leucine homozygous (LL) genotype carriers. Individuals with the LL genotype outperformed V-allele carriers in serum thyroxine (T4) concentration by 21.3-30.5 nmol/L (16.15%-24.86%; p < 0.01-0.05). Genetic differentiation induced by TG5 C422T polymorphism was determined to a lesser extent by the hormonal status of the Hereford animals. The V-allele was associated with increased carcass weight, with VV homozygotes significantly outperforming LL individuals by 45.0 kg (13.61%; p < 0.05). The T allele at the TG5 gene polymorphism was associated with more intense lipogenesis and less protein synthesis in muscle tissue and these effects were enhanced in the homozygous state. Young animals with the TT variant of the TG5 gene exhibited a significantly superior polyunsaturated fatty acid/saturated fatty acid ratio of 0.012 units (p < 0.01). Carriers of the LL genotype were characterized by minimum amino acid content in muscle tissue. Heterozygous bulls exceeded LL homozygotes in the sum of essential amino acids by 3.09% (p = 0.10) and non-essential amino acids by 1.9% (p < 0.05). The development of breeding programs for the Hereford breed should be carried out considering genetic features that determine the formation of economic traits in animals. Analysis of polymorphisms in the TG5 gene is a promising method for the early diagnosis of the fatty acid composition of beef. Identification of polymorphisms in the GH gene allows the prediction of higher productivity potential and amino acid composition of meat. The different effects of the GH and TG5 genes on the development of various economic traits allowed us to determine further vectors for scientific research on their complex associations in Hereford cattle, which will be useful for planning effective breeding schemes.

Study on the difference and clinical value of serum amino acids in patients with laryngeal squamous cell carcinoma

Objective:To detect the differences in types and levels of amino acids in the peripheral serum of patients with laryngeal squamous cell carcinoma and non-tumor patients, and explore their relationship with clinical parameters of laryngeal squamous cell carcinoma as well as their clinical value in diagnosis. Methods:High-performance liquid chromatography-tandem mass spectrometry（HPLC-MS） was employed to detect the serum amino acid contents and levels of 62 patients diagnosed with laryngeal carcinoma and 141 non-tumor patients at the First Affiliated Hospital of Jinzhou Medical University between September 2018 and February 2021. The study compared the differences in 22 non-essential and essential amino acids found in the serum between the experimental group and the control group. An ROC curve and risk scoring formula of multivariate linear logic regression model was utilized to evaluate the efficiency of serum amino acids in the early diagnosis of laryngeal carcinoma. Results:There were significant differences in the contents of fourteen types of amino acids between the experimental and control groups, with thirteen amino acids showing higher levels in the experimental group（P<0.05）. Seven of these amino acids were essential, including phenylalanine, threonine, leucine, valine, histidine, tyrosine, and citrulline. The other six amino acids were non-essential, including arginine, asparagine, cysteine, glycine, ornithine, and proline. Interestingly, the content of homocysteine in the experimental group was lower than that in the control group（P=0.024）. Further analysis showed that patients with laryngeal squamous cell carcinoma in TNM stage Ⅰ and Ⅱ had higher serum methionine levels compared to those in stages Ⅲ and Ⅳ（P=0.026）. In addition, the content of serum histidine was higher in patients with poorly differentiated squamous cell carcinoma compared to those with well-differentiated squamous cell carcinoma（P=0.041）. The level of asparagine in the serum of patients with laryngeal squamous cell carcinoma older than 64 years old was lower than that in patients younger than 64 years old（P=0.033）. The level of tryptophan in the serum of patients with a smoking history was lower than that in patients without a smoking history（P=0.033）. The level of citrulline in the serum of patients with a history of alcohol consumption was higher than that in patients with no history of alcohol consumption（P=0.003）. ROC curve analysis showed that out of the 14 different amino acids between the experimental and control groups, citrulline and cysteine were relatively effective as independent factors in the diagnosis of laryngeal squamous cell carcinoma, with an AUC of 0.856 and 0.850, respectively. Arginine was the most sensitive factor in the diagnosis of laryngeal squamous cell carcinoma（AUC=0.855）. However, citrulline alone had the highest specificity（0.830） in the diagnosis of laryngeal squamous cell carcinoma, and the combination of 12 amino acids significantly improved the diagnostic efficiency of laryngeal squamous cell carcinoma, with an AUC of 0.946, sensitivity of 0.887, and specificity of 0.894. A risk score formula for a multivariate logistic regression model was established based on the differential amino acid content in the serum. The risk score of laryngeal squamous cell carcinoma group was higher than that of the non-tumor group（P<0.001）. The AUC of risk score in the diagnosis of laryngeal squamous cell carcinoma was 0.953 with sensitivity and specificity of 0.957 and 0.855. Conclusion:This study found that there are differences in the contents of 14 amino acids among which 13 amino acids were increased in serum of patients with laryngeal squamous cell carcinoma, and were associated with age, clinical stage, pathological differentiation, smoking, and drinking. Combined detection of 12 amino acids can improve the diagnostic efficiency of laryngeal squamous cell carcinoma and serve as potential markers for the auxiliary diagnosis of laryngeal squamous cell carcinoma using peripheral blood samples. Additionally, the established risk score model was found to be more effective in the diagnosis of laryngeal squamous cell carcinoma, indicating its important potential value as an auxiliary diagnostic tool.

Genome-wide SNPs and candidate genes underlying the genetic variations for protein and amino acids in pearl millet (Pennisetum glaucum) germplasm

Main conclusionA total of 544 significant marker-trait associations and 286 candidate genes associated with total protein and 18 amino acids were identified. Thirty-three candidate genes were found near the strong marker trait associations (– log10P ≥ 5.5).Pearl millet (Pennisetum glaucum) is largely grown as a subsistence crop in South Asia and sub-Saharan Africa. It serves as a major source of daily protein intake in these regions. Despite its importance, no systematic effort has been made to study the genetic variations of protein and amino acid content in pearl millet germplasm. The present study was undertaken to dissect the global genetic variations of total protein and 18 essential and non-essential amino acids in pearl millet, using a set of 435 K Single Nucleotide Polymorphisms (SNPs) and 161 genotypes of the Pearl Millet Inbred Germplasm Association Panel (PMiGAP). A total of 544 significant marker-trait associations (at P < 0.0001; – log10P ≥ 4) were detected and 23 strong marker-trait associations were identified using Bonferroni’s correction method. Forty-eight pleiotropic loci were found in the genome for the studied traits. In total, 286 candidate genes associated with total protein and 18 amino acids were identified. Thirty-three candidate genes were found near strongly associated SNPs. The associated markers and the candidate genes provide an insight into the genetic architecture of the traits studied and are going to be useful in breeding improved pearl millet varieties in the future. Availabilities of improved pearl millet varieties possessing higher protein and amino acid compositions will help combat the rising malnutrition problem via diet.

Dynamic response of essential amino acid biosynthesis in Buchnera aphidicola to supplement sub-optimal host nutrition

The endosymbiotic bacterium Buchnera aphidicola allows its host Acyrthosiphon pisum to utilise a nutritionally limited phloem sap diet without significant mortality by providing essential amino acids (EAAs), which it biosynthesises de novo via complex pathways consisting of multiple enzymes. Previous studies have reported how non-essential amino acids (NEAAs) provided by the host are utilised by B. aphidicola, along with how genes within the biosynthetic pathways respond to amino acid deficiency. Although the effect on B. aphidicola gene expression upon the removal of a single EAA and multiple NEAAs from the A. pisum diet has been reported, little is known about the effects of the complete simultaneous removal of multiple EAAs, especially branched-chain amino acids (BCAAs). To investigate this, A. pisum was provided with amino acid deficient diets ilv- (lacking isoleucine, leucine, valine) or thra- (lacking threonine, methionine, lysine). Due to their involvement in the production of several amino acids, the expression of genes ilvC, ilvD (both involved in isoleucine, leucine and valine biosynthesis) and thrA (involved in threonine, methionine and lysine biosynthesis) was analysed and the expression of trpC (involved in tryptophan biosynthesis) was used as a control. Survival was reduced significantly when A. pisum was reared on ilv- or thra- (P < 0.001 and P = 0.000 respectively) compared to optimal artificial diet and was significantly lower on ilv- (P < 0.001) than thra-. This is likely attributed to the EAAs absent from ilv- being required at higher concentrations for aphid growth, than those EAAs absent from thra-. Expression of ilvC and ilvD were upregulated 2.49- and 2.08-fold (respectively) and thrA expression increased 2.35- and 2.12-fold when A. pisum was reared on ilv- and thra- (respectively). The surprisingly large upregulation of thrA when reared on ilv- is likely due to threonine being an intermediate in isoleucine biosynthesis. Expression of trpC was not affected by rearing on either of the two amino acid deficient diets. To our knowledge this study has shown, for the first time, how genes within the biosynthetic pathways of an endosymbiont respond to the simultaneous complete omission of multiple EAAs as well as all three BCAAs (leucine, isoleucine, valine), from the host diet.

Effects of isoleucine, lysine, valine, and a group of nonessential amino acids on mammary amino acid metabolism in lactating dairy cows

Intracellular AA regulate milk protein synthesis within the mammary gland by modifying mammary plasma flow (MPF) and AA transporter activity. Amino acid transporters catalyze translocation using Na+ gradient, substrate gradient (uniporters), and exchange mechanisms; further, they exhibit specificity for individual AA or groups of AA with similar side-chain properties within each transport system. Nonessential AA are actively transported through Na+-dependent transporters and, thus, are often used as intracellular currencies for EAA transport through exchange transporters. Therefore, it was hypothesized that individual EAA supplementation would compete with other EAA for shared transporters, and supplementation with Ala, Gln, and Gly would stimulate EAA transport through exchange transporters. Ten primiparous lactating dairy cows were divided into 2 groups based on milk production and were randomly assigned to treatment sequences within 2 balanced 5 × 5 Latin squares by group. Period length was 14 d. Treatments were 9-d jugular infusions of (1) saline; (2) 34.5 g of Val per day; (3) a ratio of 32.7 g of Ala to 40 g of Gln to 26.7 g of Gly per day (AQG); (4) 43 g of Lys per day; or (5) 33.5 g of Ile per day. All cows were fed a common base diet formulated to contain 15.0% CP. Infusions of Ile, Lys, or AQG did not affect milk protein or milk production; however, Val infusion decreased both. The effects of Val infusion on milk protein production appeared to be partially driven by decreased DMI. The decline in milk protein percentage indicated that milk lactose production was also affected. Additionally, Val infusion increased MPF efficiency (MPF/milk; L/L) by approximately 44%. Infusion of Val tended to decrease or decreased mammary net uptakes of Lys, Leu, Met, and total AA. Infusion of Ile tended to increase its mammary net uptakes but did not affect any other AA. Infusions of Lys and AQG did not affect any mammary net uptakes. Infusion of Val tended to decrease Phe and total NEAA mammary clearance rates. Infusion with AQG stimulated Tyr clearance rates and tended to decline system N mammary clearance rates. Ratios of branched-chain AA mammary uptake to milk protein output (U:O) did not differ from 1 for Val-infused cows, which indicated that little intramammary catabolism was occurring. Additionally, the average NEAA U:O in response to all treatments except Val was 0.70, but Val-infused cows had NEAA U:O that averaged 0.09, indicating increased synthesis within the glands. The effects of Val on mammary net clearance rates of multiple EAA support the incorporation of AA limitations in ration optimizers to prevent AA imbalances. It is possible that oversupplementation of EAA other than Val may also decrease DMI and mammary activity. Identifying efficiency apexes for each of the EAA will allow more precise diet formulation and supplementation, leading to improved production efficiency.

Exploring the nutritional profiles and dietary value of indigenous fish species from the Mathabanga River in Bangladesh

The study aimed to address the pervasive issue of inadequate nutrition in Bangladesh by analyzing eight distinct fish species, a pivotal step toward developing fish powder as a promising dietary supplement for nutritional enhancement. Samples from the Mathabhanga River in Chuadanga were rigorously processed and oven-dried to assess their nutritional properties, focusing on proximate composition, mineral content, and amino acid profile. Among the studied fish species, C. reba demonstrated the highest energy content (198.56 Kcal/100 g, p < 0.001), with notably elevated crude protein content (16.99 g/100 g, p < 0.001) compared to all except N. notopterus. The mineral composition order in fish powders was Ca > P > Fe > Na > Mg. Leucine emerged as the predominant essential amino acid (EAA) (6.84 to 32.15 mg/g, p < 0.001) among the species. O. pabo exhibited notably higher total EAA (∑EAA) levels (124.30 mg/g, p < 0.05) compared to other species. P. ticto showed a significantly higher ratio of total essential and non-essential amino acid content (∑EAA/∑NEAA) (0.41, p < 0.05) compared to other species. These findings underscored the nutritional value of the studied fish species, advocating their utilization as a dietary supplement to address malnutrition in Bangladesh.

Amino Acid Profile Alterations in Phenylketonuria: Implications for Clinical Practice.

Patients with phenylketonuria (PKU) must restrict their intake of phenylalanine, which can also affect the levels of other essential and non-essential amino acids due to inadequate supply. Therefore, our objective was to assess amino acids in serum samples from 20 PKU patients and compare them with results from 51 healthy subjects. A sample analysis was conducted using liquid chromatography-tandem mass spectrometry. We obtained levels of 28 substances, including amino acids, biogenic amines, carnitine, and acetylcarnitine. Kynurenine (p = 0.000001), tyrosine (p = 0.0002), asparagine (p = 0.001), proline (p = 0.012), and the kynurenine/tryptophan ratio (p < 0.000001) were identified as features that differed between the studied groups, being significantly lower in patients with PKU. Glycine (p = 0.000012), putrescine (p = 0.0055), asymmetric dimethylarginine (p = 0.01), creatinine (p = 0.035) levels, as well as the total level of glucogenic amino acids (p = 0.0018), and the ratios of putrescine/ornithine (p = 0.003) and citrulline/ornithine (p = 0.0043) were significantly higher in the PKU group. In conclusion, the amino acid profiles in patients with PKU differ significantly from those in healthy peers, with potential clinical implications. These findings confirm the importance of metabolic testing in clinical practice and highlight the necessity for adequate dietary monitoring and adjustment.

Embryonic morphology and biochemical differences in Scylla paramamosain: Investigating berried and non-berried phenotypes

Scylla paramamosain, an economically valuable crustacean with a particular emphasis on female mud crabs possessing mature ovaries, is demanded extensively due to its exceptional market value. The study focused on understanding the proximate and biochemical compositions of eggs, ovaries and hepatopancreas across different maturation stages. Nine berried and non-berried female mud crabs were meticulously analyzed morphologically and microscopically. The protein contents were significantly higher in the ovary of berried S. paramamosain at stage-II (∼ 72 %) surpassing hepatopancreas and the non-berried counterparts (∼ 42 %), whereas, the egg showed slightly higher protein contents at the 1st maturation stage (∼ 67 %). The fatty acids, including Saturated Fatty acids (SFAs), Mono-unsaturated Fatty acids (MUFAs) and Poly-unsaturated Fatty acids (n6-PUFAs and n3-PUFAs), showed an incremental decrease during all the maturation stages of berried S. paramamosain across all three organelles. Interestingly, these fatty acids were significantly higher in the hepatopancreas (∼ 32, 31, 7 and 26, respectively) and lower in the ovary (∼ 28, 28, 6 and 25, respectively) of non-berried S. paramamosain. The eicosapentanoic acid (EPA) and docosahexanoic acid (DHA) showed an incremental decrease in eggs and hepatopancrease of berried and non-berried S. paramamosain in maturation stages I-III (∼ 11, 10, 9 % and ∼ 19, 15, 10 %, respectively, and ∼ 10, 9, 8, 8 % and ∼17, 16, 13, 12 %, respectively), which were significantly higher in the ovary of non-berried S. paramamosain (∼ 9 and 12 %, respectively) when compared with any of these maturation stages of the berried S. paramamosain (∼ means 7 and 8.33 %, respectively). The Total Essential Amino Acids (ΣEAA) and Total Non-Essential Amino Acids (ΣNEAA) displayed an incremental decrease in the egg and an increase in the ovary and hepatopancreas during the mentioned maturation stages. The glutamic acid, however, showed an incremental decrease in the egg and an increase in the ovary and hepatopancreas of berried S. paramamosain which was significantly prominent in the ovary of non-berried S. paramamosain.

Effects of β-Alanine Supplementation on Subjects Performing High-Intensity Functional Training.

β-alanine, a non-essential amino acid found in the diet and produced through nucleotide catabolism, is significant for muscle performance due to its role in carnosine synthesis. This study aims to assess the impact of a 4-week β-alanine supplementation on neuromuscular fatigue in individuals engaging in High-Intensity Functional Training (HIFT) and its subsequent effect on sports performance, distinguishing between central fatigue from the CNS and peripheral fatigue from the muscular system. This study (a randomized controlled trial) comprised a total of 27 subjects, who were divided into two groups. Group A (the control group) was administered sucrose powder, while Group B (the experimental group) was given β-alanine powder. The subjects were randomly assigned to either the experimental or control groups. This study lasted four weeks, during which both groups participated in high-intensity interval training (HIFT) on the first day to induce fatigue and work close to their VO2 max. Statistically significant changes were in the sports performance variables, specifically vertical jump and jumping power (p = 0.027). These changes were observed only in the group that had been supplemented with β-alanine. Nevertheless, no alterations were observed in any other variables, including fatigue, metabolic intensity of exercise, or perceived intensity (p > 0.05). A four-week β-alanine intake program demonstrated an improvement in the capacity of subjects, as evidenced by enhanced vertical jump and power performance. Nevertheless, it does result in discernible alterations in performance.

Plasma amino acid profiles in thalassaemia major with iron overload

Introduction: Iron overload in thalassaemia major patients mainly occurs due to periodic transfusions. When iron exceeds transferrin capacity, non-transferrin bound iron accumulates and causes tissue damage, including in the gastrointestinal tract, resulting in impaired enterocyte function and amino acid absorption. The aim of this study was to evaluate amino acid profiles in patients with thalassaemia major after repeated transfusions and chelation. Methods: Whole blood amino acids were analysed from dried blood spots using liquid chromatography tandem mass spectrometry. This study consisted of two parts: a cross-sectional and a cohort study in thalassaemia-β-major patients. In the cross-sectional study, amino acid profiles were analysed in 219 thalassaemia patients who received routine transfusion and chelation therapy, and 60 healthy control subjects. The cohort study included 21 subjects, from whom blood samples were taken at pre-transfusion, 1-day posttransfusion, one and three months post-chelation to evaluate changes in amino acid levels. Results: There were significant differences between amino acid levels in thalassaemia subjects and controls. Positive correlations were found between serum iron and transferrin with age, also between transferrin with proline, valine, phenylalanine, aspartic acid, and glutamic. Phenylalanine and aspartic acid were significantly lower in subjects with transferrin lower than 180 µg/dL. Significant correlations were found between haemoglobin with essential and non-essential amino acid groups. From the cohort study, significant changes were observed in glycine, alanine, leucine, and aspartic acid. Conclusion: Amino acid profiles in thalassaemia patients differed compared to healthy controls, even after transfusion and chelation. Phenylalanine and aspartic acid were significantly lower in subjects with low transferrin levels.

Effects of alkaline extraction on the physicochemical and functional properties of protein concentrates obtained from Vigna mungo and Phaseolus vulgaris L. legumes

Legumes are well-known as sources of nutritionally desirable plant proteins. The objective of this research was to investigate the effects of alkaline extraction on the functional and antioxidant properties of protein concentrates obtained from Black gram (Vigna mungo) and red kidney bean (Phaseolus vulgaris L.) legumes. The alkaline extraction at pH 9.0 for soluble protein revealed significantly (p&lt;0.05) the highest protein content (71-74%). The total essential and non-essential amino acids of Black gram and red kidney bean proteins increased approximately 3-fold when compared to the amino acid content of the flour. The molecular weight profile of the Black gram (BGP) and red kidney bean (RKBP) protein concentrates ranged from 12 to 100 kDa and 16 to 160 kDa, respectively. Results showed that the BGP and RKBP absorbed soybean oil in the range of 2.49 to 2.67 g of oil/ g protein. The protein concentrates had strong emulsion forming and stabilizing activity. In addition, the antioxidant activities of BGP presented significantly the highest capacity to scavenge ABTS•+ with a value of 421.80 mg TEAC/g sample. We conclude that these proteins have the potential to be used as ingredients to formulate functional foods against oxidative stress.

Optimization of Biodegradation of Common Bean Biomass for Fermentation Using Trichoderma asperellum WNZ-21 and Artificial Neural Networks

This study showcases a promising approach to sustainably unlocking plant biomass residues by combining biodegradation with artificial intelligence to optimize the process. Specifically, we utilized the definitive screening design (DSD) and artificial neural networks (ANNs) to optimize the degradation of common bean biomass by the endophytic fungus Trichoderma asperellum WNZ-21. The optimized process yielded a fungal hydrolysate rich in 12 essential and non-essential amino acids, totaling 18,298.14 μg/g biomass. GC-MS analysis revealed four potential novel components not previously reported in microbial filtrates or plants and seven components exclusive to plant sources but not reported in microbial filtrates. The hydrolysate contained phenolic, flavonoid, and tannin compounds, as confirmed by FT-IR analysis. High-resolution transmission electron microscopy depicted structures resembling amino acid micelles and potential protein aggregates. The hydrolysate exhibited antioxidant, antibacterial, and anticancer properties and innovatively induced apoptotic modulation in the MCF7 cancer cell line. These findings underscore the potential of ANN-optimized fermentation for various applications, particularly in anticancer medicine due to its unique composition and bioactivities. The integration of the DSD and ANNs presents a novel technique for biomass biodegradation, warranting the valorization of plant biomass and suggesting a further exploration of the new components in the fungal hydrolysate. This approach represents the basic concept for exploring other biomass sources and in vivo studies.

Pseudomonas aeruginosa Recombinant L-asparaginase: PEGylation with Low Molecular Weight Polyethylene Glycol, Molecular Dynamics Simulation, In vitro and In vivo Serum half-life and Biochemical Characterization.

Microbial L-asparaginase (L-ASNase, EC 3.5.1.1) is a pivotal biopharmaceutical drug-protein that catalyzes the hydrolysis of the non-essential amino acid L-asparagine (L-Asn) into L-aspartic acid (L-Asp) and ammonia , resulting in deplenishing the cellular L-Asn pool, which leads to the ultimate death of the L-asparagine synthetase (L-ASNS) deficient cancerous cells. This study aimed to investigate the impact of conjugating low molecular weight polyethylene glycol to recombinant P. aeruginosa L-ASNase by examining the pharmacokinetic properties, affinity towards the substrate, and enzyme stability prior to and following the reaction. The recombinant P. aeruginosa L-ASNase was affinity purified and then PEGylated by attaching polyethylene glycol (MW= 330 Da) site-specifically to the protein's N-terminus end. After which, the PEGylated L-ASNase was examined by SDS-PAGE (15%), FTIR, and UV/Vis spectrophotometry and subsequently biochemically characterized. The Km and Vmax values of free P. aeruginosa rL-ASNase were determined to be 0.318 ±1.76 mM and 2915 μmol min-1and following the PEGylation, they were found to be 0.396 ±1.736 mM and 3193 μmol min-1, respectively. Polyethylene glycol (330 Da) has markedly enhanced LASNase thermostability at 37, 45, 50, and 55 °C, as opposed to the free enzyme, which retained 19.5% after 1 h of incubation at 37 °C. The PEGylated L-ASNase was found to be stable upon incubation with human serum for 28 h, in contrast to the sharp decline in the residual bioactivity of the free rL-ASNase after 4 h incubation. Accordingly, an in vivo study was used for validation, and it demonstrated that PEGylated rL-ASNase exhibited longer bioactivity for 24 h, while the free form's activity vanished entirely from the rats' blood sera after 8 h. Molecular dynamics simulation indicated that PEG (330 Da) has affected the hydrodynamic volume of L-ASNase and increased its structural stability. Docking analysis has explored the position of PEG with respect to binding sites and predicted a similar binding affinity to that of the free enzyme. For the first time, recombinant L-ASNase was modified by covalently attaching PEG (330 Da). The resultant novel proposed PEGylated rL-ASNase with remarkably increased stability and prolonged in vivo half-life duration, which could be considered an alternative to mitigate the high molecular weight of PEGylation's drawbacks.

Effect of Different Fertilizer Types on Quality of Foxtail Millet under Low Nitrogen Conditions.

In order to clarify the effect of different fertilizers on foxtail millet quality under low nitrogen conditions, we used JGNo.21 and LZGNo.2 as experimental materials and set up five treatments, including non-fertilization, nitrogen, phosphorus, compound, and organic fertilizers, to study the regulation of different fertilizer types on agronomic traits, nutrient fractions, and pasting characteristics of foxtail millet under low nitrogen conditions. Compared with the control, all of the fertilizers improved the agronomic traits of JGNo.21 to a certain extent. Nitrogen and compound fertilizer treatments reduced the starch content of JGNo.21; the starch content was reduced by 0.55% and 0.07% under nitrogen and compound fertilizers treatments. Phosphorus and organic fertilizers increased starch content, and starch content increased by 0.50% and 0.56% under phosphorus and organic fertilizer treatments. The effect of each fertilizer treatment on protein content was completely opposite to that of starch; different fertilizer treatments reduced the fat content of JGNo.21 and increased the fiber content. Among them, nitrogen and phosphorus fertilizers increased the yellow pigment content; the yellow pigment content increased by 1.21% and 2.64% under nitrogen and phosphorus fertilizer treatments. Organic and compound fertilizers reduced the content of yellow pigment; the yellow pigment content was reduced by 3.36% and 2.79% under organic and compound fertilizer treatments. Nitrogen and organic fertilizers increased the fat content of LZGNo.2; the fat content increased by 2.62% and 1.98% under nitrogen, organic fertilizer treatment. Compound and phosphorus fertilizer decreased the fat content; the fat content decreased by 2.16% and 2.90% under compound and phosphorus fertilizer treatment. Different fertilizer treatments reduced the cellulose and yellow pigment content of LZGNo.2. The content of essential, non-essential, and total amino acids of JGNo.21 was increased under compound and nitrogen fertilizer treatments and decreased under organic and phosphorus fertilizer treatments. The content of essential, non-essential, and total amino acids of LZGNo.2 was significantly higher under compound, nitrogen, and organic fertilizer treatments compared with control and significantly decreased under phosphorus fertilizer treatments. Nitrogen and compound fertilizer treatments significantly reduced the values of peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity, and pasting time of each index of JGNo.21; phosphorus and organic fertilizer treatments improved the values of each index. In contrast, the pasting viscosity of LZGNo.2 increased under phosphorus fertilizer treatment and decreased under nitrogen fertilizer treatment. Reasonable fertilization can improve the quality of foxtail millet, which provides a scientific theoretical basis for improving the quality of foxtail millet.

Replacement of the massive amino acid losses induced by hemodialysis: A new treatment option proposal for a largely underestimated issue

BackgroundA series of interesting literature reports acknowledges the notable loss of essential and non-essential amino acids (EAAs and NEAAs) during hemodialysis sessions. These losses may exceed 800 g/year, thus contributing towards accelerating the onset of malnutrition in hemodialysis patients (HD). ObjectiveA novel tailored amino acid formula for oral administration was developed to replace total amounts of each individual amino acid lost during dialysis diffusive/convective HD strategies, monitoring the effects produced on nutritional and hematological status. MethodsA three-month randomized double-blind study was conducted on 30 subjects over the age of 70 years extrapolated from a total population of 86 hemodialysis patients. The 30 patients were randomly assigned to two groups: a treatment group of 15 HD patients (TG) to whom a novel mixture containing 5.4 g of AAs was administered solely on interdialytic days, and a control group of 15 HD patients (CG) who received no amino acid supplementation. The AAs mixture was administered post-dialysis at an extended interval from the end of solute and compartmental rebound to replace AA losses and optimize their role in protein anabolism. ResultsThe results obtained highlighted a significant improvement in protein intake g/kg/day (Protein Catabolic Rate, p= 0.014), and increased IgG (p=0.008) and C3 serum levels (p=0.003) in the TG group alone. Fat mass losses were initially confirmed by means of bioelectrical impedance analysis (BIA) (p=0.011) and plicometry (p<0.001) in the CG group alone, although the main objective was to preserve nutritional status and, particularly, muscle mass. The study was extended to investigate the effects produced on anemia, yielding evidence of continued positive effects three months after the end of the study in the TG group alone based on an increase in Hb levels from 11.2+0.6 to 12.1+0.6 (p=0.004) associated with a reduced demand for erythropoietin i.v. from 12928+9033 to 9286+ 5398 U.I/week (p=0.012) and iron i.v. from 75.9+55 to 71.4+33.4 mg/week (p=0.045). ConclusionsThe results obtained following oral administration of this novel tailored AA replacement mixture aimed at reinstating the high AA losses produced during hemodialysis suggest the mixture should be prescribed as a standard procedure to all HD patients.

Irisin promotes tilapia muscle cell growth and amino acid uptake via IGF-1 signaling.

Irisin is a recently discovered myokine that facilitates the browning of white adipose tissue, increases glucose uptake in skeletal muscle, and influences metabolic processes in the liver. However, its potential effects on amino acid absorption remained largely unexplored. This study aimed to elucidate the role of irisin in modulating amino acid uptake and delineate the underlying molecular mechanisms involved. To this end, juvenile tilapia were administered intraperitoneal irisin injections at 100 ng/g body weight over 8 weeks. Evaluation of various physiological parameters revealed that irisin supplementation significantly improved the specific growth rate and feed conversion efficiency while reducing feed consumption. Muscle tissue analysis revealed that irisin significantly modified the proximate composition by increasing protein content and reducing lipid levels. It also significantly raised the levels of both essential and non-essential amino acids in the muscle. Histological analysis demonstrated that irisin-stimulated muscle growth through hyperplasia rather than hypertrophy, corroborated by upregulated IGF-1 mRNA and downregulated myostatin mRNA expression. Mechanistic studies in cultured tilapia muscle cells elucidated that irisin activated integrin receptors on muscle cells, which subsequently engaged IGF-1/IGF-1R signaling. Downstream of IGF-1R activation, irisin simultaneously stimulates the ERK1/2 and PI3K/mTORC2/Akt pathways. The convergence of these pathways upregulates L-type amino acid transporter 1 expression, thereby augmenting amino acid uptake into muscle cells. In summary, irisin supplementation in tilapia leads to improved muscle growth, predominantly via hyperplasia and augmented amino acid assimilation, governed by intricate cellular signaling pathways. These findings provide valuable aquaculture applications and novel insights into muscle development.

Non-essential Amino Acids Are Needed to Attenuate ICU Acquired Muscle Weakness (ICU-AW) in a Pig Model of Sepsis Recovery

Non-essential Amino Acids Are Needed to Attenuate ICU Acquired Muscle Weakness (ICU-AW) in a Pig Model of Sepsis Recovery

Coingestion of Collagen With Whey Protein Prevents Postexercise Decline in Plasma Glycine Availability in Recreationally Active Men.

Whey protein ingestion during recovery from exercise increases myofibrillar but not muscle connective protein synthesis rates. It has been speculated that whey protein does not provide sufficient glycine to maximize postexercise muscle connective protein synthesis rates. In the present study, we assessed the impact of coingesting different amounts of collagen with whey protein as a nutritional strategy to increase plasma glycine availability during recovery from exercise. In a randomized, double-blind, crossover design, 14 recreationally active men (age: 26 ± 5years; body mass index: 23.8 ± 2.1kg·m-2) ingested in total 30g protein, provided as whey protein with 0g (WHEY), 5g (WC05); 10g (WC10), and 15g (WC15) of collagen protein immediately after a single bout of resistance exercise. Blood samples were collected frequently over 6hr of postexercise recovery to assess postprandial plasma amino acid kinetics and availability. Protein ingestion strongly increased plasma amino acid concentrations (p < .001) with no differences in plasma total amino acid availability between treatments (p > .05). The postprandial rise in plasma leucine and essential amino acid availability was greater in WHEY compared with the WC10 and WC15 treatments (p < .05). Plasma glycine and nonessential amino acid concentrations declined following whey protein ingestion but increased following collagen coingestion (p < .05). Postprandial plasma glycine availability averaged -8.9 ± 5.8, 9.2 ± 3.7, 23.1 ± 6.5, and 39.8 ± 11.0mmol·360min/L in WHEY, WC05, WC10, and WC15, respectively (incremental area under curve values, p < .05). Coingestion of a small amount of collagen (5g) with whey protein (25g) is sufficient to prevent the decline in plasma glycine availability during recovery from lower body resistance-type exercise in recreationally active men.

Exploring the Bioactive Properties and Therapeutic Benefits of Pear Pomace.

The fruit juice industry generates a significant amount of waste, with a strong impact on the environment and the economy. Therefore, researchers have been focusing on the characterization of resources considered as food waste. This work provides information about the lipophilic and polar metabolites of pear pomace flours (PPFs) as a tool that can shed more light on the bioactive potential of this residue. Using UPLC-PDA, UPLC-FLR, and GC-MS, the study identified and quantified PPF's polar and non-polar metabolites. Essential, conditional, and non-essential amino acids were found, with asparagine being the most abundant. Isoprenoids, including lutein, zeaxanthin, and carotene isomers, ranged from 10.8 to 22.9 mg/100 g dw. Total flavonoids and phenolic compounds were 520.5-636.4 mg/100 g dw and 536.9-660.1 mg/100 g dw, respectively. Tocotrienols and tocopherols were identified, with concentrations of 173.1-347.0 mg/100 g dw and 468.7-913.4 mg/100 g dw. Fatty acids were the major non-polar compounds. All fractions significantly reduced matrix metalloproteinase-9 (MMP-9) activity. Although PPF had lower antioxidant potential (3-6 mmol Trolox/100 g dw), it inhibited AChE and BuChE by 23-30% compared to physostigmine salicylate. These findings suggest that pear pomace waste can be repurposed into functional products with valuable bioactive properties by re-introducing it in the food chain.