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Glutaminase controls the first step in glutaminolysis, impacting bioenergetics, biosynthesis and oxidative stress. Two isoenzymes exist in humans, GLS and GLS2. GLS is considered prooncogenic and overexpressed in many tumours, while GLS2 may act as prooncogenic or as a tumour suppressor. Glioblastoma cells usually lack GLS2 while they express high GLS. We investigated how GLS2 expression modifies the metabolism of glioblastoma cells, looking for changes that may explain GLS2's potential tumour suppressive role. We developed LN-229 glioblastoma cells stably expressing GLS2 and performed isotope tracing using U-13C-glutamine and metabolomic quantification to analyze metabolic changes. Treatment with GLS inhibitor CB-839 was also included to concomitantly inhibit endogenous GLS. GLS2 overexpression resulted in extensive metabolic changes, altering the TCA cycle by upregulating part of the cycle but blocking the synthesis of the 6-carbon intermediates from acetyl-CoA. Expression of GLS2 caused downregulation of PDH activity through phosphorylation of S293 of PDHA1. GLS2 also altered nucleotide levels and induced the accumulation of methylated metabolites and S-adenosyl methionine. These changes suggest that GLS2 may be a key regulator linking glutamine and glucose metabolism, also impacting nucleotides and epigenetics. Future research should ascertain the mechanisms involved and the generalizability of these findings in cancer or physiological conditions. [ABSTRACT FROM AUTHOR]

In this study, to investigate the quality of wild and farmed frozen southern bluefin tuna, physicochemical analyses and sensory evaluations were conducted. Principal component analysis was then performed using the results obtained to examine the correlation between the bluefin tuna's taste characteristics and physicochemical properties. The sensory evaluation suggested differences in texture and acidity between wild and farmed fish, whereas the principal component analysis indicated differences in fatty acid and amino acid composition. Wild fish contained higher levels of docosahexaenoic acid and monounsaturated fatty acids, while farmed fish had higher levels of saturated fatty acids. Regarding free amino acids and dipeptides, wild fish had higher levels of anserine and alanine, whereas farmed fish showed higher levels of glutamine and histidine, and acidity was observed in farmed fish. Furthermore, based on the results of the principal component analysis, it was inferred that the content of inosinic acid, which is considered an umami component in fish, may have a low impact on palatability. These factors were suggested to influence the differences between wild and farmed tuna. [ABSTRACT FROM AUTHOR]

Simple Summary: In China, following the ban on feed antibiotics in 2020, the intestinal health problems of weaning piglets have become increasingly serious; however, diets supplemented with a single dietary additive for weaning piglets cannot always solve adverse problems caused by weaning. Lactic acid promotes the activity of digestive enzymes and improves the subsequent digestion of young piglets by regulating gastrointestinal pH, and it can also play an important role as an energy substance in the tricarboxylic acid cycle. Glutamine, as the most abundant free amino acid in animal organisms, can restore the defective intestinal mucosal structure and immune function caused by weaning. Dietary supplementation with lactic acid and glutamine could be a strategy for alleviating the weaning stress of piglets; however, it is unknown whether the combined addition of these has an interactive effect. In this study, we aimed to investigate the effects of dietary supplementation with lactic acid and glutamine, and their interactions, on growth performance, intestinal function, and microflora of weaning piglets. The objective of this study was to evaluate the effects of dietary addition of lactic acid and glutamine, and their interactions, on growth performance, nutrient digestibility, digestive enzyme activity, intestinal barrier functions, microflora, and expressions of intestinal development-related genes of weaning piglets. Ninety-six 24-day-old weaning piglets (Duroc × Landrace × Yorkshire, weaned at 21 ± 1 d and fed the basal diet for a 3 d adaptation period) with initial body weight of 7.24 ± 0.09 kg were randomly assigned to one of four dietary treatments with six replicates per treatment and four pigs per replicate in a 2 × 2 factorial treatment arrangements: (1) CON (a 2-period basal diet; control), (2) LS (supplemented with 2% lactic acid), (3) GS (supplemented with 1% glutamine), and (4) LGS (supplemented with 2% lactic acid and 1% glutamine). The study lasted for 28 d. On days 25–28, fresh fecal samples were collected to evaluate apparent total tract digestibility (ATTD) of nutrients. After 28 d, one weaning pig per pen was euthanized, and physiological samples obtained. Results showed that the supplementation of lactic acid improved the ADFI of the pigs (p < 0.05), while the pigs fed the glutamine diet had a greater ADFI and higher G/F (p < 0.05), and there were significant interactive effects between lactic acid and glutamine on the ADFI and G/F of the pigs (p < 0.05). The ATTD of CP and ash for pigs fed with lactic acid was significantly enhanced, and pigs fed the glutamine diet had greater ATTD of CP and ash (p < 0.05), while there were significant interactive effects between lactic acid and glutamine on the ATTD of CP and ash of the pigs (p < 0.05). Pigs fed with lactic acid exhibited greater activity of α-amylase and lipase (p < 0.05); moreover, the activity of lipase in the pigs showed a significant interactive effect between lactic acid and glutamine (p < 0.05). There was a greater villus height and villus height to crypt depth ratio in pigs fed with lactic acid (p < 0.05), and the villus height to crypt depth ratio of pigs fed with glutamine was greater (p < 0.05). There were greater GLUT2, IGF-1, TGF-β2, OCLN, and ZO-1 mRNA levels in pigs fed with lactic acid (p < 0.05), and the supplementation of glutamine increased SGLT1, GLUT2, PepT1, IGF-1, IGF-1R, TGFβ-2, GLP-2, and OCLN mRNA levels (p < 0.05), Additionally, expressions of SGLT1, GLUT2, PepT1, IGF-1, IGF-1R, TGFβ-2, GLP-2, CLDN-2, OCLN, and ZO-1 mRNA levels of pigs showed a positive interactive effect between lactic acid and glutamine (p < 0.05). Supplementation of lactic acid significantly increased the populations of Bifidobacterium in cecal digesta, Lactobacillus in colonic digesta, and the content of butyric acid in colonic digesta (p < 0.05). In addition, there were significant interactive effects between lactic acid and glutamine on populations of Bifidobacterium in cecal digesta, Lactobacillus in colonic digesta, and the content of acetic acid, butyric acid, and total VFAs in cecal digesta of the pigs (p < 0.05). Collectively, the current results indicate that dietary supplementation with lactic acid and glutamine had a positive synergistic effect on weaning pigs, which could improve growth performance through promoting the development of the small intestine, increasing digestive and barrier function, and regulating the balance of microflora in pigs, and which might be a potential feeding additive ensemble to enhance the health and growth of weaning piglets in the post-antibiotic era. [ABSTRACT FROM AUTHOR]

Dysfunction in the prefrontal cortex can lead to cognitive inflexibility due to multifactorial causes as included cardiometabolic disorders, stress, inadequate diets, as well as an imbalance of the gut–brain axis microbiota. However, these risk factors have not been evaluated jointly. The purpose of this study was to evaluate the effect of physical stress (MS: Male Stress and FS: Female Stress) and high-fat diet (MD: Male Diet and FD: Female Diet) supplementation on the gut microbiota and cognitive flexibility. Methods: The study was performed on 47 mice, 30 male (M) and 17 female (F) BALBc, exposed to chronic stress physical (S) and high-fat diet (D). Cognitive flexibility was evaluated using the Attentional Set-Shifting Test (ASST) and the gut microbiota composition in terms of relative abundance (%) and alpha–beta diversity. Results: Results showed that S and D reduced cognitive flexibility in male and female mice (p < 0.0001). Significant changes occurred in Alistipes spp. (MM vs. MS:MD; p < 0.0001), Barnesiella spp. (FC vs. FS; p = 0.0002; FC vs. FD, p = 0.0033); Dorea spp. (MC vs. MD, p = 0.0008; MM vs. MD, p < 0.0001) and Lactobacillus spp. (MC vs. MD and FM vs. FS, p < 0.0001; FM vs. MD, p = 0.0393) genera among groups. Predictive functional analysis (QIIME2 and PICRUSt2) showed a significant increase in the expression of histidine kinase, alanine dehydrogenase, glutamine synthase, glutamate synthase, arginine succinyl synthase, and tryptophan synthase genes (p < 0.05), the latter being a precursor of serotonin (5-HT). Conclusions: Chronic physical stress and a high-fat diet modify cognitive flexibility and the composition and predictive function of the gut microbiota. [ABSTRACT FROM AUTHOR]

Background: Diabetic encephalopathy (DE) is a neurological complication of diabetes marked by cognitive decline and complex metabolic disturbances. Salidroside (SAL), a natural compound with antioxidant and neuroprotective properties, has shown promise in alleviating diabetic complications. Exploring the spatial metabolic reprogramming in DE and elucidating SAL's metabolic effects are critical for deepening our understanding of its pathogenesis and developing effective therapeutic strategies. Methods: Air-flow-assisted desorption electrospray ionization–mass spectrometry imaging (AFADESI-MSI) was employed to investigate spatial metabolic alterations in the brains of db/db mice, a spontaneous DE model. The mice were treated with SAL (30 and 150 mg/kg, orally) for 12 weeks. Differential metabolites were identified and characterized using high-resolution mass spectrometry and validated against public databases. Results: Our AFADESI-MSI analysis revealed significant changes in 26 metabolites in the brains of DE mice compared to the controls. These metabolic changes indicated disruptions in glucose, glutamate-glutamine, nucleotide, lipid, choline, aspartate, and L-carnitine metabolism. Notably, glucose 6-phosphate (G6P), glutamine, adenosine, L-carnitine, and choline exhibited similar trends in both db/db mice and STZ-induced rat models of DE, suggesting their potential as reliable biomarkers. Twelve weeks of SAL treatment demonstrated a positive regulatory effect on glucose metabolism, the glutamate–glutamine cycle, and lipid metabolism. Conclusions: This study identifies key metabolic alterations in DE and demonstrates the therapeutic potential of SAL in modulating these disturbances, offering valuable insights for targeted interventions in diabetic complications. [ABSTRACT FROM AUTHOR]

Lyophyllum decastes is a commercially cultivated rare edible mushroom with high dietary and medicinal value. The mycelium physiological maturation was an important factor to the yield and quality of mushrooms obtained. However, it was impossible to obtain discriminative characteristics represented the maturity level of the mycelia from morphological features. In this article, we screened a candidate metabolite for evaluating the mycelium physiological maturation by metabolomic and transcriptomic analysis during mycelial vegetative growth stages of L. decastes. The results showed that mycelial vegetative growth 55 d had reached to physiological maturation according to the yield and quality of L. decastes, which the single bottle yield (307 g/bottle), the contents of flavonoids (2.94 mg/g dry weight), and 5 flavor amino acids (glutamate 177.90 μg/g, aspartate 95.74 μg/g, phenylalanine 31.68 μg/g, tyrosine 13.79 μg/g, and alanine 10.99 μg/g) were the highest. In addition, the metabolomic and transcriptomic analysis results showed that biosynthesis of secondary metabolites and amino acid had significant different during mycelial vegetative growth stages, and glutamine may be a candidate indicator to evaluate the mycelial physiological maturation. These findings contribute to improve our knowledge of mycelium physiological maturation and it will be used to increase mushroom yield and quality. [ABSTRACT FROM AUTHOR]

Accumulation of senescent endothelial cells (ECs) in vasculature represents a key step in the development of vascular aging and ensuing age-related diseases. Given that removal of senescent ECs may prevent disease and improve health and wellbeing, the discovery of novel biomarkers that effectively identify senescent cells is of particular importance. As crucial elements for biological pathways and reliable bioindicators of cellular processes, metabolites demand attention in this context. Using senescent human brain microvascular endothelial cells (HBMECs) displaying a secretory phenotype and significant morphological, nuclear, and enzymatic changes compared to their young counterparts, this study has shown that senescent HBMECs lose their endothelial characteristics as evidenced by the disappearance of CD31/PECAM-1 from interendothelial cell junctions. The metabolic profiling of young versus senescent HBMECs also indicates significant differences in glucose, glutamine, and fatty acid metabolism. The analysis of intracellular and secreted metabolites proposes L-proline, L-glutamate, NAD+, and taurine/hypotaurine pathway components as potential biomarkers. However, further studies are required to assess the value of these agents as potential biomarkers and therapeutic targets. [ABSTRACT FROM AUTHOR]

Dicer, a cytoplasmic type III RNase, is essential for the maturation of microRNAs (miRNAs) and is implicated in cancer progression and chemoresistance. Our previous research demonstrated that phosphorylation of Dicer at S1016 alters miRNA maturation and glutamine metabolism, contributing to gemcitabine (GEM) resistance in pancreatic ductal adenocarcinoma (PDAC). In this study, we focused on the role of Dicer phosphorylation at S1728/S1852 in GEM-resistant PDAC cells. Using shRNA to knock down Dicer in GEM-resistant PANC-1 (PANC-1 GR) cells, we examined cell viability through MTT and clonogenic assays. We also expressed phosphomimetic Dicer 2E (S1728E/S1852E) and phosphomutant Dicer 2A (S1728A/S1852A) to evaluate their effects on GEM resistance and metabolism. Our results show that phosphorylation at S1728/S1852 promotes GEM resistance by reprogramming glutamine metabolism. Specifically, phosphomimetic Dicer 2E increased intracellular glutamine, driving pyrimidine synthesis and raising dCTP levels, which compete with gemcitabine's metabolites. This metabolic shift enhanced drug resistance. In contrast, phosphomutant Dicer 2A reduced GEM resistance. These findings highlight the importance of Dicer phosphorylation in regulating metabolism and drug sensitivity, offering insights into potential therapeutic strategies for overcoming GEM resistance in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Viruses are intracellular parasites that utilize organelles, signaling pathways, and the bioenergetics machinery of the cell to replicate the genome and synthesize proteins to build up new viral particles. Mitochondria are key to supporting the virus life cycle by sustaining energy production, metabolism, and synthesis of macromolecules. Mitochondria also contribute to the antiviral innate immune response. Here, we describe the different mechanisms involved in virus–mitochondria interactions. We analyze the effects of viral infections on the metabolism of glucose in the Warburg phenotype, glutamine, and fatty acids. We also describe how viruses directly regulate mitochondrial function through modulation of the activity of the electron transport chain, the generation of reactive oxygen species, the balance between fission and fusion, and the regulation of voltage-dependent anion channels. In addition, we discuss the evasion strategies used to avoid mitochondrial-associated mechanisms that inhibit viral replication. Overall, this review aims to provide a comprehensive view of how viruses modulate mitochondrial function to maintain their replicative capabilities. [ABSTRACT FROM AUTHOR]

Simple Summary: This study explores Warburg's paradox, whereby cancer cells use both glucose and oxygen to survive, even though glucose is converted to lactate instead of being oxidized. By systematically investigating cellular metabolism during each phase of cell division and comparing the metabolic profiles of lymphoma cells and non-malignant lymphocytes, we discovered that pyruvate, the end-product of glucose metabolism, is converted into alanine. This conversion directs glutamine carbon, rather than glucose, into the TCA cycle. Furthermore, using fludarabine to selectively inhibit lymphoma cell proliferation, we showed that blocking the conversion of pyruvate to alanine disrupts the TCA cycle and interferes with the supply of nucleotides and the energy necessary for cancer cell growth. Our findings suggest that with the suppression of glucose oxidation, the conversion of pyruvate to alanine is the crucial metabolic link that connects glucose and oxygen metabolism and serves as a key component of Warburg's paradox. Background/Objectives: Warburg's metabolic paradox illustrates that malignant cells require both glucose and oxygen to survive, even after converting glucose into lactate. It remains unclear whether sparing glucose from oxidation intersects with TCA cycle continuity and if this confers any metabolic advantage in proliferating cancers. This study seeks to understand the mechanistic basis of Warburg's paradox and its overall implications for lymphomagenesis. Methods: Using metabolomics, we first examined the metabolomic profiles, glucose, and glutamine carbon labeling patterns in the metabolism during the cell cycle. We then investigated proliferation-specific metabolic features of malignant and nonmalignant cells. Finally, through bioinformatics and the identification of appropriate pharmacological targets, we established malignant-specific proliferative implications for the Warburg paradox associated with metabolic features in this study. Results: Our results indicate that pyruvate, lactate, and alanine levels surge during the S phase and are correlated with nucleotide synthesis. By using 13C1,2-Glucose and 13C6, 15N2-Glutamine isotope tracers, we observed that the transamination of pyruvate to alanine is elevated in lymphoma and coincides with the entry of glutamine carbon into the TCA cycle. Finally, by using fludarabine as a strong inhibitor of lymphoma, we demonstrate that disrupting the transamination of pyruvate to alanine correlates with the simultaneous suppression of glucose-derived nucleotide biosynthesis and glutamine carbon entry into the TCA cycle. Conclusions: We conclude that the transamination of pyruvate to alanine intersects with reduced glucose oxidation and maintains the TCA cycle as a critical metabolic feature of Warburg's paradox and lymphomagenesis. [ABSTRACT FROM AUTHOR]

Background: This study aims to identify a metabolomic signature that facilitates the classification of syncope and the categorization of the unexplained syncope (US) to aid in its management. Methods: We compared a control group (CTRL, n = 10) with a transient loss of consciousness (TLC) group divided into the OH group (n = 23) for orthostatic syncope, the NMS group (n = 26) for neuromediated syncope, the CS group (n = 9) for cardiological syncope, and the US group (n = 27) for US defined as syncope without a precise categorization after first- and second-level diagnostic approaches. Results: The CTRL and the TLC groups significantly differed in metabolic profile. A new logistic regression model has been developed to predict how the US will be clustered. Using differences in lysophosphatidylcholine with 22 carbon atom (C22:0-LPC) levels, 96% of the US belongs to the NMS and 4% to the CS subgroup. Differences in glutamine and lysine (GLN/LYS) levels clustered 95% of the US in the NMS and 5% in the CS subgroup. Conclusions: We hypothesize a possible role of C22:0 LPC and GLN/LYS in re-classifying US and differentiating it from cardiological syncope. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma is the most common and aggressive primary brain tumour, characterised by its invasive nature and complex metabolic profile. Emerging research highlights the role of amino acids (AAs) in glioblastoma metabolism, influencing tumour growth and the surrounding microenvironment. Methods: This narrative review synthesises recent pre-clinical studies focusing on the metabolic functions of AAs in glioblastoma. Key areas include the effects of AA deprivation on tumour growth, adaptive mechanisms, and the tumour microenvironment. Results: The effects related to arginine, glutamine, methionine, and cysteine deprivation have been more extensively reported. Arginine deprivation in arginine-auxotrophic glioblastomas induces apoptosis and affects cell adhesion, while glutamine deprivation disrupts metabolic pathways and enhances autophagy. Methionine and cysteine deprivation impact lipid metabolism and ferroptosis. Tumour adaptive mechanisms present challenges, and potential compensatory responses have been identified. The response of the microenvironment to AA deprivation, including immune modulation, is critical to determining therapeutic outcomes. Conclusions: Targeting AA metabolism offers a promising approach for glioblastoma treatment, with potential targeted drugs showing clinical promise. However, the complexity of tumour adaptive mechanisms and their impact on the microenvironment necessitates further research to optimise combination therapies and improve therapeutic efficacy. [ABSTRACT FROM AUTHOR]

Background/Objectives: Metabolomics provides insights into the biological underpinnings of disease development and treatment. This systematic review investigated the impact of acupuncture on metabolite levels and associated metabolic pathways using a metabolomic approach. Methods: Five databases (i.e., PubMed, Embase, Scopus, CINAHL, and Cochrane Central) were searched using terms such as "acupuncture" and "metabolites" to retrieve relevant journal articles published through January 2024. Studies utilizing mass spectrometry or nuclear magnetic resonance were included. Risk of bias was evaluated using the Cochrane Risk of Bias tool and the Newcastle–Ottawa scale. Metabolic pathway analysis was conducted using MetaboAnalyst 6.0 to identify common significant pathways affected by acupuncture. Additionally, subgroup pathway enrichment analysis identified metabolites significantly altered in more than two studies. Results: Among 4019 articles, 22 studies met inclusion criteria, examining changes in metabolomic biomarkers before and after acupuncture for various diseases and symptoms. A total of 226 metabolites showed significant changes, with 14 common metabolites altered in more than two studies (glutamine, androsterone glucuronide, choline, citric acid, decanoylcarnitine, estrone, glutathione, glycine, hypoxanthine, lactic acid, pyruvic acid, serine, proline, and sn-glycero-3-phosphocholine). Common pathways affected by acupuncture were glycine, serine, and threonine metabolism, glutathione metabolism, arginine biosynthesis, and glyoxylate and dicarboxylate metabolism. Conclusions: This review provides insights of the metabolomic mechanisms underlying acupuncture, highlighting its impact on specific metabolic pathways. Recognizing these changes can enhance acupuncture's effectiveness and support the development of personalized treatments. The findings underscore metabolomics as a valuable tool for understanding and optimizing acupuncture for various diseases and symptoms. [ABSTRACT FROM AUTHOR]

In this study, novel ergosterol peroxide (EP) derivatives were synthesized and evaluated to assess their antiproliferative activity against four human cancer cell lines (A549, HepG2, MCF-7, and MDA-MB-231). Compound 3g exhibited the most potent antiproliferative activity, with an IC50 value of 3.20 µM against MDA-MB-231. This value was 5.4-fold higher than that of the parental EP. Bioassay optimization further identified 3g as a novel glutaminase 1 (GLS1) inhibitor (IC50 = 3.77 µM). In MDA-MB-231 cells, 3g reduced the cellular glutamate levels by blocking the glutamine hydrolysis pathway, which triggered reactive oxygen species production and induced caspase-dependent apoptosis. Molecular docking indicated that 3g interacts with the reaction site of the variable binding pocket by forming multiple interactions with GLS1. In a mouse model of breast cancer, 3g showed remarkable therapeutic effects at a dose of 50 mg/kg, with no apparent toxicity. Based on these results, 3g could be further evaluated as a novel GLS1 inhibitor for triple-negative breast cancer (TNBC) therapy. [ABSTRACT FROM AUTHOR]

Intrahepatic cholangiocarcinoma (ICC) is a universally lethal malignancy with increasing incidence. However, ICC patients receive limited benefits from current drugs; therefore, we must urgently explore new drugs for treating ICC. Quinolizidine alkaloids, as essential active ingredients extracted from Sophora alopecuroides Linn, can suppress cancer cell growth via numerous mechanisms and have therapeutic effects on liver-related diseases. However, the impact of quinolizidine alkaloids on intrahepatic cholangiocarcinoma has not been fully studied. In this article, the in vitro anti-ICC activities of six natural quinolizidine alkaloids were explored. Aloperine was the most potent antitumor compound among the tested quinolizidine alkaloids, and it preferentially inhibited RBE cells rather than HCCC-9810 cells. Mechanistically, aloperine can potentially decrease glutamate content by inhibiting the hydrolysis of glutamine, reducing D-2-hydroxyglutarate levels and, consequently, leading to preferential growth inhibition in isocitrate dehydrogenase (IDH)-mutant ICC cells. In addition, aloperine preferentially resensitizes RBE cells to 5-fluorouracil, AGI-5198 and olaparib. This article demonstrates that aloperine shows preferential antitumor effects in intrahepatic cholangiocarcinoma cells harboring the mutant IDH1 by decreasing D-2-hydroxyglutarate, suggesting that aloperine could be used as a lead compound or adjuvant chemotherapy drug to treat ICC harboring the mutant IDH. [ABSTRACT FROM AUTHOR]

Background/Objectives: Free amino acids substantially contribute to energy metabolism. Also, their profile may identify (over)training status and effectiveness. The long-term effects of speed-power training on plasma free amino acid (PFAA) profiles are not known. We aimed to observe variations in PFAA levels in high-performance sprinters in a six-month training cycle. Methods: Ten male athletes (24.6 ± 3.3 years) were examined during four training phases: transition (1 month), general preparation (2 months), specific preparation (1 month), and pre-competition/competition (2 months). Venous blood was collected at rest, after exhaustive exercise, and recovery. Forty-two PFAAs were analyzed by the LC-ESI-MS/MS method. Results: Significant decreases in resting concentrations were observed between the transition and competition phases for glutamine (762 ± 117 vs. 623 ± 53 μmol∙L−1; p < 0.001, η2 = 0.47) and histidine (89 ± 15 vs. 75 ± 10 μmol∙L−1; p = 0.010, η2 = 0.27), whereas β-alanine (30 ± 7 vs. 41 ± 9 μmol∙L−1; p = 0.024, η2 = 016) and sarcosine (3.6 ± 0.4 vs. 4.8 ± 0.6 μmol∙L−1; p = 0.006, η2 = 0.188) levels increased. Between the specific and competition phases, significant decreases in the resting levels of 1-methylhistidine (22.1 ± 19.4 vs. 9.6 ± 8.8 μmol∙L−1; p = 0.14, η2 = 0.19), 3-methylhistidine (7.1 ± 1.5 vs. 6.5 ± 1.6 μmol∙L−1; p = 0.009, η2 = 0.18), citrulline (40 ± 10 vs. 29 ± 4 μmol∙L−1; p = 0.05, η2 = 0.29), and ornithine (74 ± 15 vs. 56 ± 10 μmol∙L−1; p = 0.015, η2 = 185) were noticed. Also, for β-alanine and sarcosine, the pattern of response to exercise strongly changed between the training phases. Blood ammonia levels at exhaustion decreased between the transition and competition phases (32 ± 4 vs. 23 ± 5 μmol∙L−1; p < 0.001, η2 = 0.67), while lactate, the phenylalanine–tyrosine ratio, the glutamine–glutamate ratio, hematological parameters, and cardiorespiratory indices remained at similar levels. Conclusions: Speed-power training seems to affect PFAAs involved in skeletal muscle metabolic pathways responsible for neutralizing toxic ammonia (glutamine, arginine, citrulline, ornithine), attenuating the deleterious effects of H+ ions (histidine, β-alanine), and reducing exercise-induced protein breakdown (1- and 3-methylhistidine). Our findings suggest that sprint-oriented training supports metabolic pathways that are responsible for the removal of harmful metabolites produced during exercise. [ABSTRACT FROM AUTHOR]

Simple Summary: In recent years, cancer has gradually become a terrible killer of human health. Due to various factors such as tumor heterogeneity and the complexity of the microenvironment, completely conquering cancer has always been a major problem in the scientific research community. Therefore, more detailed research and individualized treatment are essential. Everyone knows that tumor cells in the process of rapid proliferation need replenishing nutrients to sustain their energy supply. Intervention of tumor cell metabolism is gradually becoming a way to treat cancer. As an important transporter of glutamine, ASCT2 can uptake glutamine from the tumor microenvironment to support the growth and metabolism of cancer cells. Deficiency of ASCT2 can significantly inhibit tumor progression. However, not all patients benefit from this treatment. Our study aims to explore the metabolic heterogeneity of breast cancer and its related mechanisms, as well as to find metabolic-sensitive populations for further precision treatment. As a crucial amino acid, glutamine can provide the nitrogen and carbon sources needed to support cancer cell proliferation, invasion, and metastasis. Interestingly, different types of breast cancer have different dependences on glutamine. This research shows that basal-like breast cancer depends on glutamine, while the other types of breast cancer may be more dependent on glucose. Glutamine transporter ASCT2 is highly expressed in various cancers and significantly promotes the growth of breast cancer. However, the key regulatory mechanism of ASCT2 in promoting basal-like breast cancer progression remains unclear. Our research demonstrates the significant change in fatty acid levels caused by ASCT2, which may be a key factor in glutamine sensitivity. This phenomenon results from the mutual activation between ASCT2-mediated glutamine transport and lipid metabolism via the nuclear receptor PPARα. ASCT2 cooperatively promoted PPARα expression, leading to the upregulation of lipid metabolism. Moreover, we also found that C118P could inhibit lipid metabolism by targeting ASCT2. More importantly, this research identifies a potential avenue of evidence for the prevention and early intervention of basal-like breast cancer by blocking the glutamine–lipid feedback loop. [ABSTRACT FROM AUTHOR]

In this study, the effects of adding glutamate (Glu), glutamine (Gln), aspartate (Asp), and asparagine (Asn) on the flavor formation of Huangjiu were investigated, and the effect of Gln concentration on the quality, microbial community structure, and flavor development of Huangjiu was further explored. Varied Gln concentrations influenced yeast growth, sugar utilization, microbial communities, and quality attributes. Additional Gln promoted yeast cell counts and sugar depletion. It increased the complexity of bacterial co-occurrence networks and reduced the impact of stochastic processes on assembly. Correlation analysis linked microorganisms to flavor compounds. Isolation experiments verified the role of Saccharomyces cerevisiae, Aspergillus chevalieri, Bacillus altitudinis, and Lactobacillus coryniformis in flavor production under Gln conditions. This research elucidated the microbiological mechanisms by which amino acid supplementation, especially Gln, enhances Huangjiu quality by modulating microbial metabolic functions and community dynamics during fermentation. This research is significant for guiding the production of Huangjiu and enhancing its quality. [ABSTRACT FROM AUTHOR]

Simple Summary: Glutamine (Gln) plays a critical role in the development and progression of prostate cancer (PCa). Non-malignant prostate cells are not addicted to Gln, but PCa cells become Gln-dependent due to the low levels of the Gln-producing enzyme glutamine synthetase. Gln metabolism in PCa is controlled by oncogenes such as MYC, AR, and mTOR, which contribute to therapy resistance and more aggressive forms of the disease. Studies have shown that depriving PCa cells of Gln can inhibit their growth and survival and make them more sensitive to radiotherapy. Targeting Gln metabolism is, therefore, a promising approach for PCa treatment. Clinical trials are currently testing the safety and efficacy of drugs that inhibit Gln metabolism in combination with other therapies for different types of cancer, including PCa. Understanding of how tumor cells metabolically interact with their environment may help improve these treatments and patient outcomes. In this review, we present the latest advances in Gln research in PCa and insights into the current clinical trials. Glutamine (Gln) is a non-essential amino acid that is involved in the development and progression of several malignancies, including prostate cancer (PCa). While Gln is non-essential for non-malignant prostate epithelial cells, PCa cells become highly dependent on an exogenous source of Gln. The Gln metabolism in PCa is tightly controlled by well-described oncogenes such as MYC, AR, and mTOR. These oncogenes contribute to therapy resistance and progression to the aggressive castration-resistant PCa. Inhibition of Gln catabolism impedes PCa growth, survival, and tumor-initiating potential while sensitizing the cells to radiotherapy. Therefore, given its significant role in tumor growth, targeting Gln metabolism is a promising approach for developing new therapeutic strategies. Ongoing clinical trials evaluate the safety and efficacy of Gln catabolism inhibitors in combination with conventional and targeted therapies in patients with various solid tumors, including PCa. Further understanding of how PCa cells metabolically interact with their microenvironment will facilitate the clinical translation of Gln inhibitors and help improve therapeutic outcomes. This review focuses on the role of Gln in PCa progression and therapy resistance and provides insights into current clinical trials. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is the most prevalent primary liver malignancy and is a major cause of cancer-related mortality in the world. This study aimed to characterize glutamine amino acid transporter expression profiles in HCC compared to those of normal liver cells. In vitro and in vivo models of HCC were studied using qPCR, whereas the prognostic significance of glutamine transporter expression levels within patient tumors was analyzed through RNAseq. Solute carrier (SLC) 1A5 and SLC38A2 were targeted through siRNA or gamma-p-nitroanilide (GPNA). HCC cells depended on exogenous glutamine for optimal survival and growth. Murine HCC cells showed superior glutamine uptake rate than normal hepatocytes (p < 0.0001). HCC manifested a global reprogramming of glutamine transporters compared to normal liver: SLC38A3 levels decreased, whereas SLC38A1, SLC7A6, and SLC1A5 levels increased. Also, decreased SLC6A14 and SLC38A3 levels or increased SLC38A1, SLC7A6, and SLC1A5 levels predicted worse survival outcomes (all p < 0.05). Knockdown of SLC1A5 and/or SLC38A2 expression in human Huh7 and Hep3B HCC cells, as well as GPNA-mediated inhibition, significantly decreased the uptake of glutamine; combined SLC1A5 and SLC38A2 targeting had the most considerable impact (all p < 0.05). This study revealed glutamine transporter reprogramming as a novel hallmark of HCC and that such expression profiles are clinically significant. [ABSTRACT FROM AUTHOR]

Background: Sarcopenia, characterized by degenerative skeletal muscle loss, is increasingly linked to poor surgical outcomes. Glutamine, an immune-modulating formula, may stimulate muscle protein synthesis and inhibit degradation. We used the psoas major muscle area (PMMA) at the third lumbar vertebra, normalized for height (PMMA index), as a skeletal muscle indicator. This study investigates whether perioperative glutamine supplementation mitigates psoas muscle atrophy. Methods: We enrolled gastric adenocarcinoma (GA) patients undergoing gastrectomy. Computed tomography assessed the psoas muscle short axis. Muscle atrophy was estimated by changes between preoperative and three-month post-gastrectomy scans. Perioperative glutamine supplementation (PGS) comprised five-day parenteral plus one-month oral use. Propensity score matching minimized potential bias. A linear regression model predicted the association. Results: Of 516 patients analyzed (2016–2019), 100 (19.4%) received PGS. After propensity score matching, each group contained 97 cases. The PGS group showed a significantly higher median PMMA index change than the non-PGS group (0.3 vs. −0.3 cm2/m2, p = 0.004). Multivariate analysis revealed that PGS was significantly associated with increased PMMA index (coefficient = 0.60; 95% CI: 0.19–1.01; p = 0.005). Conclusions: PGS may help restore psoas muscle atrophy in GA patients undergoing gastrectomy. The underlying mechanisms likely relate to glutamine's role in protein metabolism and immune function. Further studies are needed to elucidate these mechanisms fully. [ABSTRACT FROM AUTHOR]

This paper studies the synthesis, characterization, and application of ZnFe2O4 nanoparticles for the removal of rhodamine b dye from aqueous media. Utilizing the combustion procedure, ZnFe2O4 nanoparticles were synthesized using two different fuels: glutamine (SG) and L-arginine (SA). In addition, the synthesized ZnFe2O4 nanoparticles were characterized through various techniques, including Fourier transform infrared (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy-dispersive X-ray (EDX), high resolution transmission electron microscope (HR-TEM), and Brunauer-Emmett-Teller (BET) surface area analysis. XRD analysis verified the creation of a ZnFe2O4 cubic spinel structure without any contaminants, revealing average crystallite sizes of 43.72 and 29.38 nm for the SG and SA samples, respectively. The FTIR spectra exhibited peaks indicative of metal-oxygen bond stretching, verifying the presence of a spinel formation. Elemental analysis via EDX confirmed the stoichiometric composition typical of zinc ferrite. In addition, FE-SEM imaging displayed that the SG and SA samples are composed of particles with irregular and spherical shapes, measuring average diameters of 135.11 and 59.89 nm, respectively. Furthermore, the BET surface area of the SG and SA samples is 60 and 85 m2/g, respectively. The maximum adsorption capacity of the SA sample (409.84 mg/g) towards rhodamine b dye was higher than that of the SG sample (279.33 mg/g), which was ascribed to its larger surface area and porosity. Kinetic and equilibrium studies revealed that the adsorption process of rhodamine b dye onto the SG and SA samples followed the Langmuir isotherm and pseudo-second-order model. Thermodynamic analysis indicated that the adsorption process was spontaneous, exothermic, and physical. The study concludes that ZnFe2O4 nanoparticles synthesized using L-arginine (SA) exhibit enhanced rhodamine b dye removal efficiency due to their smaller size, increased surface area, and higher porosity compared to those synthesized with glutamine (SG). The optimum conditions for the adsorption process of rhodamine b dye were found to be at pH 10, a contact time of 70 min, and a temperature of 298 K. These findings underscore the potential of L-arginine-synthesized ZnFe2O4 nanoparticles for effective and sustainable environmental cleanup applications. [ABSTRACT FROM AUTHOR]

Arrow bamboo (Fargesia qinlingensis) is endemic to the Qinling Mountains and has remarkable adaptive resilience to changing climates. However, its complete mitogenome remains unknown. Using the Illumina and PacBio HiFi sequencing platforms, we found that the mitogenome assembly of the F. qinlingensis has a multi-branched skeleton comprising three linear molecules (M1, M2, and M3), with a length of 442,368 bp and a GC content of 44.05%. Thirty-five unique PCGs were identified in the complete mitogenome, including twenty-four core structural genes, eleven noncore structural genes, three rRNAs, and sixteen tRNAs. The GCU for alanine and CAA for glutamine represented the most significant frequency (RSCU = 1.55) in the codon usage preference. A total of 51, 28, and 14 SSRs were determined on M1, M2, and M3, respectively. The mitogenome contained 149 pairs of dispersed repeats with lengths greater than 30 bp, the most abundant of which were 82 forward and 67 palindromic repeats. A long repeat sequence (14,342 bp) was characterized in mediating mitogenome recombination. DNA transfer analyses suggested that 44 MTPTs (30,943 bp, 6.99%) originated from the plastome. Among the 482 potential C-U/T RNA-editing sites predicted in 35 PCGs, ccmFn (38 times) and ccmC (36 times) shoed the highest frequency. Collinearity and phylogenetic trees revealed the close relationship between F. qinlingensis and Bambusa oldhamii. The primary features of the mitogenome of F. qinlingensis will help decipher the functional mitochondrial traits related to growth performance and climate resilience. Moreover, our findings provide insights into the evolution, environmental adaptation, and sustainable use of subalpine bamboo resources in the Qinling Mountains. [ABSTRACT FROM AUTHOR]

Chili peppers (Capsicum annuum L.) are economically valuable crops belonging to the Solanaceae family and are popular worldwide because of their unique spiciness and flavor. In this study, differences in the metabolomes of landrace (Subicho) and disease-resistant pepper cultivars (Bulkala and Kaltanbaksa) widely grown in Korea are investigated using a 1H NMR-based metabolomics approach. Specific metabolites were abundant in the pericarp (GABA, fructose, and glutamine) and placenta (glucose, asparagine, arginine, and capsaicin), highlighting the distinct physiological and functional roles of these components. Both the pericarp and placenta of disease-resistant pepper cultivars contained higher levels of sucrose and hexoses and lower levels of alanine, proline, and threonine than the traditional landrace cultivar. These metabolic differences are linked to enhanced stress tolerance and the activation of defense pathways, imbuing these cultivars with improved resistance characteristics. The present study provides fundamental insights into the metabolic basis of disease resistance in chili peppers, emphasizing the importance of multi-resistant varieties to ensure sustainable agriculture and food security. These resistant varieties ensure a stable supply of high-quality peppers, contributing to safer and more sustainable food production systems. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a fatal neuromuscular disease type of motor neuron disorder characterized by degeneration of the upper and lower motor neurons resulting in dysfunction of the somatic muscles of the body. The ALS condition is manifested in progressive skeletal muscle atrophy and spasticity. It leads to death, mostly due to respiratory failure. Within the pathophysiology of the disease, muscle energy metabolism seems to be an important part. In our study, we used blood plasma from 25 patients with ALS diagnosed by definitive El Escorial criteria according to ALSFR-R (Revised Amyotrophic Lateral Sclerosis Functional Rating Scale) criteria and 25 age and sex-matched subjects. Aside from standard clinical biochemical parameters, we used the NMR (nuclear magnetic resonance) metabolomics approach to determine relative plasma levels of metabolites. We observed a decrease in total protein level in blood; however, despite accelerated skeletal muscle catabolism characteristic for ALS patients, we did not detect changes in plasma levels of essential amino acids. When focused on alterations in energy metabolism within muscle, compromised creatine uptake was accompanied by decreased plasma creatinine. We did not observe changes in plasma levels of BCAAs (branched chain amino acids; leucine, isoleucine, valine); however, the observed decrease in plasma levels of all three BCKAs (branched chain alpha-keto acids derived from BCAAs) suggests enhanced utilization of BCKAs as energy substrate. Glutamine, found to be increased in blood plasma in ALS patients, besides serving for ammonia detoxification, could also be considered a potential TCA (tricarboxylic acid) cycle contributor in times of decreased pyruvate utilization. When analyzing the data by using a cross-validated Random Forest algorithm, it finished with an AUC of 0.92, oob error of 8%, and an MCC (Matthew's correlation coefficient) of 0.84 when relative plasma levels of metabolites were used as input variables. Although the discriminatory power of the system used was promising, additional features are needed to create a robust discriminatory model. [ABSTRACT FROM AUTHOR]

Simple Summary: L-Glutamate (Glu) and L-glutamine (Gln) are abundant amino acids in feedstuffs and ruminants. Dietary Gln is extensively utilized by ruminal microbes, but dietary Glu undergoes little catabolism by these microbes because they do not take up extracellular Glu due to the lack of the necessary transporters. Microbial proteins and dietary Glu exit the rumen into the abomasum and then the small intestine, where proteins undergo hydrolysis to release amino acids (including Glu and Gln) and small peptides for transport into enterocytes. Most dietary Gln escapes the underdeveloped rumen of preruminants, instead entering the abomasum and the small intestine. Within the enterocytes, Glu and Gln are extensively oxidized to provide ATP and are actively used to synthesize glutathione and other amino acids (alanine, ornithine, citrulline, arginine, proline, and aspartate), whereas Gln and aspartate are essential for purine and pyrimidine syntheses. Under normal feeding conditions, all diet- and rumen-derived Glu and Gln are extracted by the small intestine and, therefore, do not enter the portal circulation. De novo synthesis plays a crucial role in maintaining the homeostasis of Glu and Gln in the whole body but may be insufficient for maximal growth performance, production (e.g., lactation and pregnancy), and optimal health in ruminants. Dietary supplementation with Glu or Gln can safely improve the digestive, endocrine, and reproduction functions of ruminants and thus augment health and production parameters. Although both L-glutamate (Glu) and L-glutamine (Gln) have long been considered nutritionally nonessential in ruminants, these two amino acids have enormous nutritional and physiological importance. Results of recent studies revealed that extracellular Gln is extensively degraded by ruminal microbes, but extracellular Glu undergoes little catabolism by these cells due to the near absence of its uptake. Ruminal bacteria hydrolyze Gln to Glu plus ammonia and, intracellularly, use both amino acids for protein synthesis. Microbial proteins and dietary Glu enter the small intestine in ruminants. Both Glu and Gln are the major metabolic fuels and building blocks of proteins, as well as substrates for the syntheses of glutathione and amino acids (alanine, ornithine, citrulline, arginine, proline, and aspartate) in the intestinal mucosa. In addition, Gln and aspartate are essential for purine and pyrimidine syntheses, whereas arginine and proline are necessary for the production of nitric oxide (a major vasodilator) and collagen (the most abundant protein in the body), respectively. Under normal feeding conditions, all diet- and rumen-derived Glu and Gln are extensively utilized by the small intestine and do not enter the portal circulation. Thus, de novo synthesis (e.g., from branched-chain amino acids and α-ketoglutarate) plays a crucial role in the homeostasis of Glu and Gln in the whole body but may be insufficient for maximal growth performance, production (e.g., lactation and pregnancy), and optimal health (particularly intestinal health) in ruminants. This applies to all types of feeding systems used around the world (e.g., rearing on a milk replacer before weaning, pasture-based production, and total mixed rations). Dietary supplementation with the appropriate doses of Glu or Gln [e.g., 0.5 or 1 g/kg body weight (BW)/day, respectively] can safely improve the digestive, endocrine, and reproduction functions of ruminants to enhance their productivity. Both Glu and Gln are truly functional amino acids in the nutrition of ruminants and hold great promise for improving their health and productivity. [ABSTRACT FROM AUTHOR]

Terpinen-4-ol (T-4-O) is an important component of tea tree oil and has anti-inflammatory effects. Currently, there are very few studies on the mechanisms by which T-4-O improves lipopolysaccharide (LPS)-induced macrophage inflammation. In this study, LPS-stimulated mouse RAW264.7 macrophages were used as a model to analyze the effects of T-4-O on macrophage inflammatory factors and related metabolic pathways in an inflammatory environment. The results showed that T-4-O significantly decreased the expression levels of inflammatory cytokines induced by LPS. Cellular metabolism results showed that T-4-O significantly decreased the ratio of the extracellular acidification rate and oxygen consumption rate. Non-targeted metabolomics results showed that T-4-O mainly affected glutamine and glutamate metabolism and glycine, serine, and threonine metabolic pathways. qPCR results showed that T-4-O increased the transcript levels of GLS and GDH and promoted glutamine catabolism. Western blotting results showed that T-4-O inhibited the mTOR and IκB, thereby decreasing NF-κB activity. The overall results showed that T-4-O inhibited mTOR phosphorylation to promote glutamine metabolism and increased cell oxidative phosphorylation levels, thereby inhibiting the expression of LPS-induced inflammatory cytokines. [ABSTRACT FROM AUTHOR]

Electroencephalogram (EEG) studies have suggested compensatory brain overactivation in cognitively healthy (CH) older adults with pathological beta-amyloid(Aβ42)/tau ratios during working memory and interference processing. However, the association between glutamatergic metabolites and brain activation proxied by EEG signals has not been thoroughly investigated. We aim to determine the involvement of these metabolites in EEG signaling. We focused on CH older adults classified under (1) normal CSF Aβ42/tau ratios (CH-NATs) and (2) pathological Aβ42/tau ratios (CH-PATs). We measured plasma glutamine, glutamate, pyroglutamate, and γ-aminobutyric acid concentrations using tandem mass spectrometry and conducted a correlational analysis with alpha frequency event-related desynchronization (ERD). Under the N-back working memory paradigm, CH-NATs presented negative correlations (r = ~−0.74–−0.96, p = 0.0001–0.0414) between pyroglutamate and alpha ERD but positive correlations (r = ~0.82–0.95, p = 0.0003–0.0119) between glutamine and alpha ERD. Under Stroop interference testing, CH-NATs generated negative correlations between glutamine and left temporal alpha ERD (r = −0.96, p = 0.037 and r = −0.97, p = 0.027). Our study demonstrated that glutamine and pyroglutamate levels were associated with EEG activity only in CH-NATs. These results suggest cognitively healthy adults with amyloid/tau pathology experience subtle metabolic dysfunction that may influence EEG signaling during cognitive challenge. A longitudinal follow-up study with a larger sample size is needed to validate these pilot studies. [ABSTRACT FROM AUTHOR]

The present study evaluated the antiseizure and neuroprotective effects of sodium houttuyfonate (SH), a derivative of Houttuynia cordata Thunb. (H. cordata), in a kainic acid (KA)- induced seizure rat model and its underlying mechanism. Sprague Dawley rats were administered normal saline, SH (50 or 100 mg/kg), or carbamazepine (300 mg/kg) by oral gavage for seven consecutive days before the intraperitoneal administration of KA (15 mg/kg). SH showed antiseizure effects at a dose of 100 mg/kg; it prolonged seizure latency and decreased seizure scores. SH also significantly decreased neuronal loss in the hippocampi of KA-treated rats, which was associated with the prevention of glutamate level increase, the upregulation of glutamate reuptake-associated proteins (excitatory amino acid transporters 1–3), glutamate metabolism enzyme glutamine synthetase, the downregulation of the glutamate synthesis enzyme glutaminase, and significant alterations in the expression of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor) and NMDA (N-methyl-D-aspartic acid receptor) receptor subunits in the hippocampus. Furthermore, the effects of SH were similar to those of the antiseizure drug carbamazepine. Therefore, the results of the present study suggest that SH has antiseizure effects on KA-induced seizures, possibly through the prevention of glutamatergic alterations. Our findings suggest that SH is a potential alternative treatment that may prevent seizures by preserving the normal glutamatergic system. [ABSTRACT FROM AUTHOR]

Natural astaxanthin is in high demand due to its multiple health benefits. The microalga Haematococcus lacustris has been used for the commercial production of astaxanthin. In this study, we investigated the effects of six different media with and without a nitrogen source and supplementation with nine organic compounds on the growth and astaxanthin accumulation of H. lacustris. The highest astaxanthin contents were observed in cultures of H. lacustris in Jaworski's medium (JM), with a level of 9.099 mg/L in JM with a nitrogen source supplemented with leucine (0.65 g/L) and of 20.484 mg/L in JM without a nitrogen source supplemented with sodium glutamate (0.325 g/L). Six of the nine organic compounds examined (leucine, lysine, alanine, sodium glutamate, glutamine, and cellulose) enhanced the production of astaxanthin in H. lacustris, while malic acid, benzoic acid, and maltose showed no beneficial effects. [ABSTRACT FROM AUTHOR]

Polyglutamine diseases comprise a cluster of genetic disorders involving neurodegeneration and movement disabilities. In polyglutamine diseases, the target proteins become aberrated due to polyglutamine repeat formation. These aberrant proteins form the root cause of associated complications. The metabolic regulation during polyglutamine diseases is not well studied and needs more attention. We have brought to light the significance of regulating glutamine metabolism during polyglutamine diseases, which could help in decreasing the neuronal damage associated with excess glutamate and nucleotide generation. Most polyglutamine diseases are accompanied by symptoms that occur due to excess glutamate and nucleotide accumulation. Along with a dysregulated glutamine metabolism, the Nicotinamide adenine dinucleotide (NAD+) levels drop down, and, under these conditions, NAD+ supplementation is the only achievable strategy. NAD+ is a major co-factor in the glutamine metabolic pathway, and it helps in maintaining neuronal homeostasis. Thus, strategies to decrease excess glutamate and nucleotide generation, as well as channelizing glutamine toward the generation of ATP and the maintenance of NAD+ homeostasis, could aid in neuronal health. Along with understanding the metabolic dysregulation that occurs during polyglutamine diseases, we have also focused on potential therapeutic strategies that could provide direct benefits or could restore metabolic homeostasis. Our review will shed light into unique metabolic causes and into ideal therapeutic strategies for treating complications associated with polyglutamine diseases. [ABSTRACT FROM AUTHOR]

Specialized cancer treatments have the potential to exploit glutamine dependence to increase patient survival rates. Glutamine diagnostics capable of tracking a patient's response to treatment would enable a personalized treatment dosage to optimize the tradeoff between treatment success and dangerous side effects. Current clinical glutamine testing requires sophisticated and expensive lab-based tests, which are not broadly available on a frequent, individualized basis. To address the need for a low-cost, portable glutamine diagnostic, this work engineers a cell-free glutamine biosensor to overcome assay background and signal-to-noise limitations evident in previously reported studies. The findings from this work culminate in the development of a shelf-stable, paper-based, colorimetric glutamine test with a high signal strength and a high signal-to-background ratio for dramatically improved signal resolution. While the engineered glutamine test is important progress towards improving the management of cancer and other health conditions, this work also expands the assay development field of the promising cell-free biosensing platform, which can facilitate the low-cost detection of a broad variety of target molecules with high clinical value. [ABSTRACT FROM AUTHOR]

Simple Summary: This retrospective study focused on 23 patients diagnosed with Hepatocellular Carcinoma (HCC), utilizing the Liver Imaging Reporting and Data System (LI-RADS) for classification. This system aids in the non-invasive diagnosis of HCC, potentially eliminating the need for a diagnostic biopsy. Patients were selected based on their diagnosis, confirmed either via imaging methods that identified advanced liver nodules or via histopathological findings consistent with HCC, including specific protein markers. The study aimed to assess the histopathological changes resulting from prior local interventions, such as trans-arterial chemoembolization or radiofrequency ablation, and their impact on the tumor's response to subsequent immune therapies. Key findings indicated variations in alpha-fetoprotein levels and increased expression of the immune marker PD-L1 in untreated patients, suggesting a more aggressive cancer progression in these individuals. The study's conclusions support the use of liver biopsy in refining therapeutic approaches for HCC, particularly in recurrent cases post-intervention, to enhance personalized immune therapy strategies. Background: The Liver Imaging Reporting and Data System (LI-RADS) combines standardized terminology with a classification system for imaging findings in patients with HCC, therefore rendering diagnostic biopsy unnecessary in many cases. This retrospective study included 23 patients with a biopsy diagnosis of HCC, performed either before or after local interventional procedures, in order to evaluate the histopathologic changes induced by previous procedures and their potential influence on the response to immune therapy. Material and Methods: The study encompassed a cohort of patients diagnosed with Hepatocellular Carcinoma (HCC). Diagnosis was established via contrast-enhanced computer tomography or magnetic resonance imaging that identified LI-RADS-5 nodules in conjunction with historical liver disease and elevated alpha-fetoprotein (AFP) levels or via histological examination confirming positivity for glypican3, heat shock protein 70, and glutamine synthetase. The study detailed the liver disease etiology, LI-RADS scores, characteristics and dimensions of HCC nodules, serum AFP concentrations, Edmondson–Steiner grading, and the expression of programmed cell death ligand 1 (PD-L1) in the tumor cells. Results: Among the study's cohort of Hepatocellular Carcinoma (HCC) patients, a portion had not received any prior treatments, while the remainder experienced local HCC recurrence following trans-arterial chemoembolization or radiofrequency ablation. Observations indicated elevated alpha-fetoprotein (AFP) levels in those who had not undergone any previous interventions, showing statistical significance. The Edmondson–Steiner classification predominantly identified grade III differentiation across patients, irrespective of their treatment history. Furthermore, an increase in intra-tumoral programmed cell death ligand 1 (PD-L1) expression was noted in patients who had not been subjected to previous therapies. Conclusion: Liver biopsy offers valuable insights for patients with Hepatocellular Carcinoma (HCC), assisting in the tailoring of immune therapy strategies, particularly in cases of recurrence following prior local interventions. [ABSTRACT FROM AUTHOR]

Simple Summary: Y-27632, as a pyrimidine derivative, is commonly used for low-temperature preservation of cell cytoskeleton. However, the Y-27632 small molecule has not yet been used in research on low-temperature preservation of goat semen. This study aims to address the issue of low temperature-induced loss of sperm motility in goats by using Y-27632, and explore the regulation of Y-27632 on goat sperm metabolism. We evaluate the protective effect of Y-27632 on the quality of low temperature-preserved goat semen by detecting goat sperm motility, antioxidant capacity, mitochondrial activity, cholesterol levels, and metabolomics analysis. This study indicates that Y-27632 improves the preservation quality of goat sperm by protecting the sperm plasma membrane, enhancing sperm antioxidant capacity, and increasing D-glutamine and D-glutamate metabolism levels. The protective effect of Y-27632 on semen has also been confirmed through artificial insemination. The results of this study provide some new insights into the application of Y-27632 in low-temperature preservation of goat semen, and promote the application of Y-27632 in low-temperature preservation of semen. Y-27632, as a cytoskeleton protector, is commonly used for low-temperature preservation of cells. Goat sperm are prone to damage to the cytoskeleton under low-temperature conditions, leading to a loss of sperm vitality. However, the Y-27632 small molecule has not yet been used in research on low-temperature preservation of goat semen. This study aims to address the issue of low temperature-induced loss of sperm motility in goats by using Y-27632, and explore the regulation of Y-27632 on goat sperm metabolism. At a low temperature of 4 °C, different concentrations of Y-27632 were added to the sperm diluent. The regulation of Y-27632 on the quality of low temperature-preserved goat semen was evaluated by detecting goat sperm motility, antioxidant capacity, mitochondrial activity, cholesterol levels, and metabolomics analysis. The results indicated that 20 µM Y-27632 significantly increased plasma membrane integrity (p < 0.05), and acrosome integrity (p < 0.05) and sperm motility (p < 0.05), increased levels of superoxide dismutase (SOD) and catalase (CAT) (p < 0.01), increased total antioxidant capacity (T-AOC) (p < 0.05), decreased levels of malondialdehyde (MDA) and reactive oxygen species (ROS) (p < 0.01), and significantly increased mitochondrial membrane potential (MMP). The levels of ATP, Ca2+, and TC in sperm increased (p < 0.01). Twenty metabolites with significant differences were identified, with six metabolic pathways having a significant impact, among which the D-glutamic acid and D-glutamine metabolic pathways had the most significant impact. The artificial insemination effect of goat semen treated with 20 μM Y-27632 was not significantly different from that of fresh semen. This study indicates that Y-27632 improves the quality of low-temperature preservation of sperm by protecting the sperm plasma membrane, enhancing sperm antioxidant capacity, regulating D-glutamine and D-glutamate metabolism, and promoting the application of low-temperature preservation of semen in artificial insemination technology. [ABSTRACT FROM AUTHOR]

The seed of Citrullus lanatus mucosospermus, known as egusi, is versatile and explored for its oil and flour functionality. Raw flour can be used as a raw material in a nutritional program due to its oil-rich, remarkably high protein content, and richness in omega-6 fatty acids. There is a need to explore eco-friendly defatting methods using the supercritical CO2 extraction method (SFECO2) to preserve this seed's generic richness and to control the flour–oil ratio in processing formulations. The supercritical fluid extraction method uses temperature, pressure, and CO2 flow rate to determine the best yield and extraction parameters. Defatted egusi flour (DEF) was extracted using three runs. Firstly, at 60 °C, 30 g/h, and 450 bar (DEF1); secondly, at 55 °C, 30 g/h, and 600 bar (DEF2); and thirdly, extraction was performed at 75 °C, 30 g/h and 600 bar (DEF3). Trace and major elements were analysed using Agilent 7700 quadruple ICP-MS (Agilent Technologies Network, Palo Alto, CA, USA) and Thermo Cap 6200 ICP-AES (Thermo Scientific, Waltham, MA, USA), respectively. The sugar was separated on a gas chromatograph coupled to a Mass Selective Detector (MSD). The fundamental pasting property measurements were performed using a Rapid Visco Analyser RVA 4500 Perten instrument Sin 214 31208-45 Australia. Data analysis was conducted using IBM SPSS version 29 software (v. 2022). The protein content of defatted egusi flour ranged from 48.4 for DEF2 to 60.4% w/w for DEF1 and differed significantly, with a rich amino acid high in glutamine ranging from 9.8 to 12.9 g/100 g). DEF2 (512.0 cP) showed the highest peak viscosity and was the most viscous among the samples. Defatted flour with lower temperature and lower pressure (60 °C and 450 bar) offered the best nutritional properties, proffering defatted egusi flour from SFECO2, a novel flour for dietary programs. [ABSTRACT FROM AUTHOR]

Acute kidney injury represents a significant threat in cardiac surgery regarding complications and costs. Novel preventive approaches are needed, as the therapeutic modalities are still limited. As experimental studies have demonstrated, glutamine, a conditionally essential amino acid, might have a protective role in this setting. Moreover, the levels of glutamine after the cardiopulmonary bypass are significantly lower. In clinical practice, various trials have investigated the effects of glutamine supplementation on cardiac surgery with encouraging results. However, these studies are heterogeneous regarding the selection criteria, timing, dose, outcomes studied, and way of glutamine administration. This narrative review aims to present the potential role of glutamine in cardiac surgery-associated acute kidney injury prevention, starting from the experimental studies and guidelines to the clinical practice and future directions. [ABSTRACT FROM AUTHOR]

Theanine, polyphenols, and caffeine not only affect the flavor of tea, but also play an important role in human health benefits. However, the specific regulatory mechanism of Se NMs on fat-reducing components is still unclear. In this study, the synthesis of fat-reducing components in Fuding Dabai (FDDB) tea was investigated. The results indicated that the 100-bud weight, theanine, EGCG, total catechin, and caffeine contents of tea buds were optimally promoted by 10 mg·L−1 Se NMs in the range of 24.3%, 36.2%, 53.9%, 67.1%, and 30.9%, respectively. Mechanically, Se NMs promoted photosynthesis in tea plants, increased the soluble sugar content in tea leaves (30.3%), and provided energy for the metabolic processes, including the TCA cycle, pyruvate metabolism, amino acid metabolism, and the glutamine/glutamic acid cycle, ultimately increasing the content of amino acids and antioxidant substances (catechins) in tea buds; the relative expressions of key genes for catechin synthesis, CsPAL, CsC4H, CsCHI, CsDFR, CsANS, CsANR, CsLAR, and UGGT, were significantly upregulated by 45.1–619.1%. The expressions of theanine synthesis genes CsTs, CsGs, and CsGOGAT were upregulated by 138.8–693.7%. Moreover, Se NMs promoted more sucrose transfer to the roots, with the upregulations of CsSUT1, CsSUT2, CsSUT3, and CsSWEET1a by 125.8–560.5%. Correspondingly, Se NMs enriched the beneficial rhizosphere microbiota (Roseiarcus, Acidothermus, Acidibacter, Conexicter, and Pedosphaeraceae), enhancing the absorption and utilization of ammonium nitrogen by tea plants, contributing to the accumulation of theanine. This study provides compelling evidence supporting the application of Se NMs in promoting the lipid-reducing components of tea by enhancing its nitrogen metabolism. [ABSTRACT FROM AUTHOR]

Iridoid components have been reported to have significant neuroprotective effects. However, it is not yet clear whether the efficacy and mechanisms of iridoid components with similar structures are also similar. This study aimed to compare the neuroprotective effects and mechanisms of eight iridoid components (catalpol (CAT), genipin (GE), geniposide (GEN), geniposidic acid (GPA), aucubin (AU), ajugol (AJU), rehmannioside C (RC), and rehmannioside D (RD)) based on corticosterone (CORT)-induced injury in PC12 cells. PC12 cells were randomly divided into a normal control group (NC), model group (M), positive drug group (FLX), and eight iridoid administration groups. Firstly, PC12 cells were induced with CORT to simulate neuronal injury. Then, the MTT method and flow cytometry were applied to evaluate the protective effects of eight iridoid components on PC12 cell damage. Thirdly, a cell metabolomics study based on ultra-performance liquid chromatography–quadrupole–time-of-flight mass spectrometry (UPLC-Q/TOF-MS) was performed to explore changes in relevant biomarkers and metabolic pathways following the intervention of administration. The MTT assay and flow cytometry analysis showed that the eight iridoid components can improve cell viability, inhibit cell apoptosis, reduce intracellular ROS levels, and elevate MMP levels. In the PCA score plots, the sample points of the treatment groups showed a trend towards approaching the NC group. Among them, AU, AJU, and RC had a weaker effect. There were 38 metabolites (19 metabolites each in positive and negative ion modes, respectively) identified as potential biomarkers during the experiment, among which 23 metabolites were common biomarkers of the eight iridoid groups. Pathway enrichment analysis revealed that the eight iridoid components regulated the metabolism mainly in relation to D-glutamine and D-glutamate metabolism, arginine biosynthesis, the TCA cycle, purine metabolism, and glutathione metabolism. In conclusion, the eight iridoid components could reverse an imbalanced metabolic state by regulating amino acid neurotransmitters, interfering with amino acid metabolism and energy metabolism, and harmonizing the level of oxidized substances to exhibit neuroprotective effects. [ABSTRACT FROM AUTHOR]

The gut–brain axis is increasingly understood to play a role in neuropsychiatric disorders. The probiotic bacterium Lactobacillus (L.) reuteri and products of tryptophan degradation, specifically the neuroactive kynurenine pathway (KP) metabolite kynurenic acid (KYNA), have received special attention in this context. We, therefore, assessed relevant features of KP metabolism, namely, the cellular uptake of the pivotal metabolite kynurenine and its conversion to its primary products KYNA, 3-hydroxykynurenine and anthranilic acid in L. reuteri by incubating the bacteria in Hank's Balanced Salt solution in vitro. Kynurenine readily entered the bacterial cells and was preferentially converted to KYNA, which was promptly released into the extracellular milieu. De novo production of KYNA increased linearly with increasing concentrations of kynurenine (up to 1 mM) and bacteria (107 to 109 CFU/mL) and with incubation time (1–3 h). KYNA neosynthesis was blocked by two selective inhibitors of mammalian kynurenine aminotransferase II (PF-048559989 and BFF-122). In contrast to mammals, however, kynurenine uptake was not influenced by other substrates of the mammalian large neutral amino acid transporter, and KYNA production was not affected by the presumed competitive enzyme substrates (glutamine and α-aminoadipate). Taken together, these results reveal substantive qualitative differences between bacterial and mammalian KP metabolism. [ABSTRACT FROM AUTHOR]

This document is an editorial introducing a special issue titled "Effects of Environmental Organic Pollutants on Environment and Human Health: The Latest Updates." The issue focuses on volatile organic compounds (VOCs) and persistent organic pollutants (POPs), which are harmful to the environment and human health. The articles in the issue cover a range of topics, including the pollution characteristics and risk assessment of VOCs in different cities, the effects of exposure to POPs on health, and the ecological risks associated with organic pollutants. The research presented in this special issue provides valuable information for policymakers and researchers in the field. [Extracted from the article]

Sugarcane (Saccharum spp. hybrids) and its processed products have supported local industries such as those in the Nansei Islands, Japan. To improve the sugarcane quality and productivity, breeders select better clones by evaluating agronomic characteristics, such as commercially recoverable sugar and cane yield. However, other constituents in sugarcane remain largely unutilized in sugarcane breeding programs. This study aims to establish a data-driven approach to analyze agronomic characteristics from breeding programs. This approach also determines a correlation between agronomic characteristics and free amino acid composition to make breeding programs more efficient. Sugarcane was sampled in clones in the later stage of breeding selection and cultivars from experimental fields on Tanegashima Island. Principal component analysis and hierarchical cluster analysis using agronomic characteristics revealed the diversity and variability of each sample, and the data-driven approach classified cultivars and clones into three groups based on yield type. A comparison of free amino acid constituents between these groups revealed significant differences in amino acids such as asparagine and glutamine. This approach dealing with a large volume of data on agronomic characteristics will be useful for assessing the characteristics of potential clones under selection and accelerating breeding programs. [ABSTRACT FROM AUTHOR]

The neuroblastoma cell lines SH-SY5Y and Neuro2A are commonly utilized models in neurobiological research. DMEM supplemented with different nutrients and 5–10% Fetal Calf Serum (FCS) is typically used for culturing these cell lines. During special treatments, a reduced FCS content is often deployed to reduce cellular proliferation or the content of bioactive compounds. The impact of the reduction of FCS in culture media on the metabolic profile of SH-SY5Y and Neuro2A cells is currently unknown. Using an Amplex Red Assay, this study showed that the consumption of L-glutamine decreased after FCS reduction. Glucose and pyruvate consumption increased in both cell lines after the reduction of FCS. Thus, lactate production also increased with reduced FCS concentration. The reduction of FCS in the cell culture medium resulted in a reduced aerobic ATP production for SH-SY5Y cells and a complete shut down of aerobic ATP production for Neuro2A cells, measured using the Seahorse XF Real-Time ATP Rate Assay. Utilizing the Seahorse XF Glutamine Oxidation Stress Test, Neuro2A cells showed an increased utilization of L-glutamine oxidation after reduction of FCS. These results indicate that changes in FCS concentration in culture media have an impact on the different energy production strategies of SH-SY5Y and Neuro2A cells which must be considered when planning special treatments. [ABSTRACT FROM AUTHOR]

In arterial hypertension, the dysregulation of several metabolic pathways is closely associated with chronic immune imbalance and inflammation progression. With time, these disturbances lead to the development of progressive disease and end-organ involvement. However, the influence of cholecalciferol on metabolic pathways as a possible mechanism of its immunomodulatory activity in obesity-related hypertension is not known. In a phase 2, randomized, single-center, 24-week trial, we evaluated, as a secondary outcome, the serum metabolome of 36 age- and gender-matched adults with obesity-related hypertension and vitamin D deficiency, before and after supplementation with cholecalciferol therapy along with routine medication. The defined endpoint was the assessment of circulating metabolites using a nuclear magnetic resonance-based metabolomics approach. Univariate and multivariate analyses were used to evaluate the systemic metabolic alterations caused by cholecalciferol. In comparison with normotensive controls, hypertensive patients presented overall decreased expression of several amino acids (p < 0.05), including amino acids with ketogenic and glucogenic properties as well as aromatic amino acids. Following cholecalciferol supplementation, increases were observed in glutamine (p < 0.001) and histidine levels (p < 0.05), with several other amino acids remaining unaffected. Glucose (p < 0.05) and acetate (p < 0.05) decreased after 24 weeks in the group taking the supplement, and changes in the saturation of fatty acids (p < 0.05) were also observed, suggesting a role of liposoluble vitamin D in lipid metabolism. Long-term cholecalciferol supplementation in chronically obese and overweight hypertensives induced changes in the blood serum metabolome, which reflected systemic metabolism and may have fostered a new microenvironment for cell proliferation and biology. Of note, the increased availability of glutamine may be relevant for the proliferation of different T-cell subsets. [ABSTRACT FROM AUTHOR]

Sodium–glucose co-transporter 1 (SGLT1) and sodium-dependent neutral amino acid transporter (B0AT1) are mainly expressed on the membrane of enterocytes, a type of epithelial cell found in the intestines. In addition to their physiological role in the absorption of nutrients, a protective role in the integrity of the intestinal barrier has been established. The natural ligands of SGLT1 (d-glucose) and of B0AT1 (l-glutamine) can trigger a protective anti-inflammatory effect on the intestinal epithelium. The literature suggests the activation of common intracellular pathways upon engagement of the two transporters, whose functional forms are composed of oligomers or clusters. Simultaneous activation of these two co-transporters could lead to a potential multitarget and synergistic anti-inflammatory effect. Therefore, nanoplatforms containing multiple copies of the ligands could represent chemical tools to study the potential simultaneous activation of the two co-transporters. For these reasons, in this study, a set of different gold nanoparticles decorated with derivatives of d-glucose and of l-glutamine were designed and prepared. In particular, the synthesis of suitable sulfur-ending functionalized ligand derivatives, including a C-glucoside derivative, their anchoring to gold nanoparticles and their physical–chemical characterization have been carried out. The obtained nanostructures could represent promising multifunctional platforms for further investigation of the existence of possible multitarget and synergistic effects toward the two co-transporters SGLT1 and B0AT1. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is a highly contagious and hemorrhagic disease caused by infection with the African swine fever virus (ASFV), resulting in a mortality rate of up to 100%. Currently, there are no effective treatments and commercially available vaccines for ASF. Therefore, it is crucial to identify biochemicals derived from host cells that can impede ASFV replication, with the aim of preventing and controlling ASF. The ASFV is an acellular organism that promotes self-replication by hijacking the metabolic machinery and biochemical resources of host cells. ASFV specifically alters the utilization of glucose and glutamine, which are the primary metabolic sources in mammalian cells. This study aimed to investigate the impact of glucose and glutamine metabolic dynamics on the rate of ASFV replication. Our findings demonstrate that ASFV infection favors using glutamine as a metabolic fuel to facilitate self-replication. ASFV replication can be substantially inhibited by blocking glutamine metabolism. The metabolomics analysis of the host cell after late-stage ASFV infection revealed a significant disruption of normal glutamine metabolic pathways due to the abundant expression of PLA (phenyllactic acid). Pretreatment with PLA also inhibited ASFV proliferation and glutamine consumption following infection. The metabolomic analysis also showed that PLA pretreatment greatly slowed down the metabolism of amino acids and nucleotides that depend on glutamine. The depletion of these building blocks directly hindered the replication of ASFV by decreasing the biosynthetic precursors produced during the replication of ASFV's progeny virus. These findings provide valuable insight into the possibility of pursuing the development of antiviral drugs against ASFV that selectively target metabolic pathways. [ABSTRACT FROM AUTHOR]

Plants can utilize different N forms, including organic and inorganic N resources, and show great differences in the utilization efficiency of each N form among species and genotypes within a species. Previously, we found that the Tibetan wild barley genotype (XZ16) was better in the utilization of organic nitrogen in comparison with the cultivated barley genotype (Hua30). In this study, the metabolite profiles of the two barley genotypes were comprehensively compared in their response to four N forms, including nitrate (NO3−), ammonium (NH4+), urea, and glycine. The macro and micro nutrient concentrations in shoots were mostly found to be higher in the nitrate and urea treatments than in ammonium and glycine in both the genotypes. XZ16 had higher concentrations of nutrient ions in the glycine treatment, but Hua30 accumulated more nutrients in the ammonium treatment. Among a total of 163 differentially regulated metabolites, the highest up-regulation and highest down-regulation values were found in XZ16 in the glycine and urea treatments, respectively. Some important metabolites, such as proline, glutamine, serine, asparagine, L-homoserine, aspartic acid, putrescine, ornithine, and 4-aminobutyrate, were up-regulated in the glycine treatment in both the genotypes with a higher fold change in XZ16 than that in Hua30. Similarly, fructose-6-PO4, aconitic acid, and isocitrate were only up-regulated in XZ16 in the glycine treatment. Here, we concluded that the genotype XZ16 exhibited a better response to the glycine treatment, while Hua30 showed a better response to the NH4+ treatment, which is attributed to the better utilization of glycine-N and NH4+-N, respectively. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of dietary l-glutamine (Gln) supplementation on the morphology and function of the intestine and the growth of muscle in piglets. In this study, sixteen 21-day-old piglets were randomly divided into two groups: the Control group (fed a basal diet) and the Gln group (fed a basal diet supplemented with 0.81% Gln). Blood, gut, and muscle samples were collected from all piglets on Day 20 of the trial. Compared with the Control group, the supplementation of Gln increased (p < 0.05) the villus height, villus width, villus surface area, and villus height/crypt depth ratio of the small intestine. Furthermore, the supplementation of Gln increased (p < 0.05) total protein, total protein/DNA, and RNA/DNA in both the jejunum and ileum. It also increased (p < 0.05) the concentrations of carnosine and citrulline in the jejunal mucosa, as well as citrulline and cysteine concentrations in the ileum. Conversely, Gln supplementation decreased (p < 0.05) Gln concentrations in both the jejunum and ileum, along with β-aminoisobutyric acid and 1-Methylhistidine concentrations, specifically in the ileum. Subsequent research revealed that Gln supplementation increased (p < 0.05) the mRNA levels for glutathione-S-transferase omega 2 and interferon-β in the duodenum. In addition, Gln supplementation led to an increase (p < 0.05) in the number of Lactobacillus genus in the colon, but a decrease (p < 0.05) in the level of HSP70 in the jejunum and the activity of diamine oxidase in plasma. Also, Gln supplementation reduced (p < 0.05) the mRNA levels of glutathione-S-transferase omega 2 and interferon stimulated genes, such as MX1, OAS1, IFIT1, IFIT2, IFIT3, and IFIT5 in both the jejunum and ileum, and the numbers of Clostridium coccoides, Enterococcus genus, and Enterobacterium family in the colon. Moreover, Gln supplementation enhanced (p < 0.05) the concentrations of total protein, RNA/DNA, and total protein/DNA ratio in the longissimus dorsi muscle, the concentrations of citrulline, ornithine, arginine, and hydroxyproline, and the mRNA level of peptide transporter 1, while reducing the contents of hydrogen peroxide and malondialdehyde and the mRNA level of glutathione-S-transferase omega 2 in the longissimus dorsi muscle. In conclusion, dietary Gln supplementation can improve the intestinal function of piglets and promote the growth of the longissimus dorsi muscle. [ABSTRACT FROM AUTHOR]

Augmentation of glycoprotein synthesis requirements induces endoplasmic reticulum (ER) stress, activating the unfolded protein response (UPR) and triggering unconventional XBP1 splicing. As a result, XBP1s orchestrates the expression of essential genes to reduce stress and restore homeostasis. When this mechanism fails, chronic stress may lead to apoptosis, which is thought to be associated with exceeding a threshold in XBP1s levels. Glycoprotein assembly is also affected by glutamine (Gln) availability, limiting nucleotide sugars (NS), and preventing compliance with the increased demands. In contrast, increased Gln intake synthesizes ammonia as a by-product, potentially reaching toxic levels. IgA2m(1)-producer mouse myeloma cells (SP2/0) were used as the cellular mammalian model. We explored how IgA2m(1)-specific productivity (qIgA2m(1)) is affected by (i) overexpression of human XBP1s (h-XBP1s) levels and (ii) Gln availability, evaluating the kinetic behavior in batch cultures. The study revealed a two and a five-fold increase in qIgA2m(1) when lower and higher levels of XBP1s were expressed, respectively. High h-XBP1s overexpression mitigated not only ammonia but also lactate accumulation. Moreover, XBP1s overexpressor showed resilience to hydrodynamic stress in serum-free environments. These findings suggest a potential application of h-XBP1s overexpression as a feasible and cost-effective strategy for bioprocess scalability. [ABSTRACT FROM AUTHOR]

Simple Summary: Glutamine, vital for the body's functions, is pivotal in cancer metabolism as it influences tumor growth. However, cancer cells' complex adaptive metabolic dynamics raise concerns about potential limitations in glutamine antagonism strategies to impede tumor growth. Similarly, while glutamine supplementation shows promise in supporting cancer patients, careful considerations are necessary to address possible interactions with ongoing treatments and concerns about inadvertent tumor growth stimulation. Recent studies have shed light on the effects of glutamine on the epigenetic regulation of cancer cells and the enhancement of anti-cancer immune functions, providing valuable insights for potential therapeutic advancements. Understanding the intricacies and challenges of glutamine interventions is essential for optimizing their potential benefits in cancer treatment and patient well-being. Glutamine, a multifaceted nonessential/conditionally essential amino acid integral to cellular metabolism and immune function, holds pivotal importance in the landscape of cancer therapy. This review delves into the intricate dynamics surrounding both glutamine antagonism strategies and glutamine supplementation within the context of cancer treatment, emphasizing the critical role of glutamine metabolism in cancer progression and therapy. Glutamine antagonism, aiming to disrupt tumor growth by targeting critical metabolic pathways, is challenged by the adaptive nature of cancer cells and the complex metabolic microenvironment, potentially compromising its therapeutic efficacy. In contrast, glutamine supplementation supports immune function, improves gut integrity, alleviates treatment-related toxicities, and improves patient well-being. Moreover, recent studies highlighted its contributions to epigenetic regulation within cancer cells and its potential to bolster anti-cancer immune functions. However, glutamine implementation necessitates careful consideration of potential interactions with ongoing treatment regimens and the delicate equilibrium between supporting normal cellular function and promoting tumorigenesis. By critically assessing the implications of both glutamine antagonism strategies and glutamine supplementation, this review aims to offer comprehensive insights into potential therapeutic strategies targeting glutamine metabolism for effective cancer management. [ABSTRACT FROM AUTHOR]

Oxidative modifications of amino acid side chains in proteins are a hallmark of oxidative stress, and they are usually regarded as structural damage. However, amino acid oxidation may also have a protective effect and may serve regulatory or structural purposes. Here, we have attempted to characterize the global redox role of the 20 proteinogenic amino acids in animals by analyzing their usage frequency in 5 plausible evolutionary paradigms of increased oxidative burden: (i) peroxisomal proteins versus all proteins, (ii) mitochondrial proteins versus all proteins, (iii) mitochondrially encoded respiratory chain proteins versus all mitochondrial proteins, (iv) proteins from long-lived animals versus those from short-lived animals, and (v) proteins from aerobic, free-living animals versus those from facultatively anaerobic animals. We have found that avoidance of cysteine in the oxidative condition was the most pronounced and significant variation in the majority of comparisons. Beyond this preeminent pattern, only local signals were observed, primarily increases in methionine and glutamine as well as decreases in serine and proline. Hence, certain types of cysteine oxidation appear to enforce its proteome-wide evolutionary avoidance despite its essential role in disulfide bond formation and metal ligation. The susceptibility to oxidation of all other amino acids appears to be generally unproblematic, and sometimes advantageous. [ABSTRACT FROM AUTHOR]