Altered Amino Acid Metabolism Research Articles

Metabolic Reprogramming of Neutrophils in the Tumor Microenvironment: Emerging Therapeutic Targets.

Neutrophils are pivotal in the immune system and have been recognized as significant contributors to cancer development and progression. These cells undergo metabolic reprogramming in response to various stimulus, including infections, diseases, and the tumor microenvironment (TME). Under normal conditions, neutrophils primarily rely on aerobic glucose metabolism for energy production. However, within the TME featured by hypoxic and nutrient-deprived conditions, they shift to altered anaerobic glycolysis, lipid metabolism, mitochondrial metabolism and amino acid metabolism to perform their immunosuppressive functions and facilitate tumor progression. Targeting neutrophils within the TME is a promising therapeutic approach. Yet, focusing on their metabolic pathways presents a novel strategy to enhance cancer immunotherapy. This review synthesizes the current understanding of neutrophil metabolic reprogramming in the TME, with an emphasis on the underlying molecular mechanisms and signaling pathways. Studying neutrophil metabolism in the TME poses challenges, such as their short lifespan and the metabolic complexity of the environment, necessitating the development of advanced research methodologies. This review also discusses emerging solutions to these challenges. In conclusion, given their integral role in the TME, targeting the metabolic pathways of neutrophils could offer a promising avenue for cancer therapy.

Amino acids and CART distinguish A-β+ Ketosis-Prone Diabetes from type 1 and type 2 diabetes during hyperglycemic crises.

When clinically stable, patients with A-β+ Ketosis-Prone Diabetes (KPD) manifest unique markers of amino acid metabolism. Biomarkers differentiating KPD from type 1 (T1D) and type 2 diabetes (T2D) during hyperglycemic crises would accelerate diagnosis and management. Compare serum metabolomics of KPD, T1D and T2D patients during hyperglycemic crises, and utilize Classification and Regression Tree (CART) modeling to distinguish these forms of diabetes. Urban hospital emergency center. Adults with KPD, T1D and T2D during hyperglycemic crises (with or without diabetic ketoacidosis (DKA), and healthy controls. Comparisons of serum metabolite and hormonal profiles, and CART analysis. Group differences in concentrations of amino acids, their metabolites and relationship to glucose counterregulatory hormones; C-peptide cutoffs and analytes to distinguish KPD, T1D and T2D. Concentrations of most amino acids were similar in KPD and T1D and lower compared to T2D (P<0.05). Glucagon and cortisol concentrations were correlated with 3-methylhistidine and blood urea nitrogen in KPD but not in T1D. A C-peptide cutoff of 0.496 ng/mL differentiated T1D from KPD during DKA. CART revealed that a regression model based on the concentrations of β-hydroxybutyrate, C-peptide, glucagon, alpha-keto-β-methylvalerate, cystine and myristoyl-L-carnitine distinguished KPD from T1D and T2D. During DKA, KPD and T1D patients have similarly altered amino acid profiles that differentiate them from T2D patients. Elevated protein catabolic hormones drive altered amino acid metabolism in KPD, rather than insulin deficiency as with T1D. A combination of 6 analytes differentiates KPD from T1D and T2D during hyperglycemic crises.

Gut microbiota modulation in cardiac cell therapy with immunosuppression in a nonhuman primate ischemia/reperfusion model

Gut microbiota affect transplantation outcomes; however, the influence of immunosuppression and cell therapy on the gut microbiota in cardiovascular care remains unexplored. We investigated gut microbiota dynamics in a nonhuman primate (NHP) cardiac ischemia/reperfusion model while under immunosuppression and receiving cell therapy with human induced pluripotent stem cell (hiPSC)-derived endothelial cells (EC) and cardiomyocytes (CM). Both immunosuppression and EC/CM co-treatment increased gut microbiota alpha diversity. Immunosuppression promoted anaerobes, such as Faecalibacterium, Streptococcus, Anaerovibrio and Dialister, and altered amino acid metabolism and nucleosides/nucleotides biosynthesis in host plasma. EC + CM cotreatment favors Phascolarctobacterium, Fusicatenibacter, Erysipelotrichaceae UCG-006, Veillonella and Mailhella. Remarkably, gut microbiota of the EC/CM co-treatment group resembled that of the pre-injury group, and the NHPs exhibited a metabolic shift towards amino acid and fatty acid/lipid biosynthesis in plasma following cell therapy. The interplay between shift in microbial community and host homeostasis during treatment suggests gut microbiome modulation could improve cell therapy outcomes.

Plasma metabolome reveals altered oxidative stress, inflammation, and amino acid metabolism in dogs with idiopathic epilepsy.

Idiopathic epilepsy (IE) is the most common chronic neurological disease in dogs and an established natural animal model for human epilepsy types with genetic and unknown etiology. However, the metabolic pathways underlying IE remain largely unknown. Plasma samples of healthy dogs (n = 39) and dogs with IE (n = 49) were metabolically profiled (n = 121 known target metabolites) and fingerprinted (n = 1825 untargeted features) using liquid chromatography coupled to mass spectrometry. Dogs with IE were classified as mild phenotype (MP; n = 22) or drug-resistant (DR; n = 27). All dogs received the same standard adult maintenance diet for a minimum of 20 days (35 ± 11 days) before sampling. Data were analyzed using a combination of univariate (one-way analysis of variance or Kruskal-Wallis rank sum test), multivariate (limma, orthogonal partial least squares-discriminant analysis), and pathway enrichment statistical analysis. In dogs with both DR and MP IE, a distinct plasma metabolic profile and fingerprint compared to healthy dogs was observed. Metabolic pathways involved in these alterations included oxidative stress, inflammation, and amino acid metabolism. Moreover, significantly lower plasma concentrations of vitamin B6 were found in MP (p = .001) and DR (p = .005) compared to healthy dogs. Our data provide new insights into the metabolic pathways underlying IE in dogs, further substantiating its potential as a natural animal model for humans with epilepsy, reflected by related metabolic changes in oxidative stress metabolites and vitamin B6. Even more, several metabolites within the uncovered pathways offer promising therapeutic targets for the management of IE, primarily for dogs, and ultimately for humans.

Metabolic profiling reveals altered amino acid and fatty acid metabolism in children with Williams Syndrome

Williams Syndrome (WS) is a rare neurodevelopmental disorder with a prevalence of 1 in 7500 to 1 in 20,000 individuals, caused by a microdeletion in chromosome 7q11.23. Despite its distinctive clinical features, the underlying metabolic alterations remain largely unexplored. This study employs targeted metabolomics to investigate the metabolic characteristics of children with WS. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we identified significant dysregulation of 15 metabolites, with 11 upregulated and 4 downregulated. Notably, amino acids such as alanine, proline, and arginine were significantly elevated. Fatty acid metabolism showed pronounced upregulation of long-chain saturated fatty acids (C18:0, C20:0, C22:0, C24:0, C26:0, and C28:0) and downregulation of long-chain unsaturated fatty acids (C18:2 LA, C22:6 DHA, C16:1 PLA, and t-C18:1 EA), except for upregulated nervonic acid (C24:1) and arachidonic acid (C20:4). Metabolic pathway analysis highlighted disruptions in arginine synthesis, arginine/proline metabolism, alanine, aspartate and glutamate metabolism, biosynthesis of unsaturated fatty acids, linoleic acid metabolism, and arachidonic acid metabolism. This study provides the first comprehensive analysis of amino acid and fatty acid metabolism in children with WS, offering insights into the disorder’s complex metabolic landscape. Further validation in larger cohorts is essential to confirm these findings and their potential as biomarkers and therapeutic targets.

Altered amino and fatty acids metabolism in Sudanese prostate cancer patients: insights from metabolic analysis.

Prostate cancer (PCa) management presents a multifaceted clinical challenge, intricately linking oncological considerations with cardiovascular health. Despite the recognized importance of lipid metabolism and hypertension in this interwoven relationship, their involvement in PCa development remains partially understood. This study aimed to explore variations in plasma metabolome among Sudanese PCa patients and their associated comorbidities. Plasma samples were collected from 50 patients across four hospitals in Sudan and profiled by nuclear magnetic resonance (NMR) spectroscopy. One-dimensional proton NMR spectra were acquired for each sample using standard nuclear Overhauser effect spectroscopy pulse sequence presat on a 500 MHz Bruker Avance III HD NMR spectrometer. Metabolite concentrations were quantified using R scripts developed in-house. Univariate and multivariate analyses were generated in the R software. Patients were categorized into four distinct metabotypes based on their metabolic profiles, and statistical analyses were conducted to evaluate the significance of observed differences. Our findings revealed high levels of fatty acids, phospholipids, cholesterol, valine, leucine, and isoleucine associated with non-hypertensive patients. In contrast, hypertensive patients were associated with high GlycA and GlycB levels and altered amino acid metabolism. These findings underscore the intricate interplay between metabolic dysregulation and hypertension in PCa patients. Further research is warranted to elucidate the precise molecular pathways underlying lipid metabolism in PCa and to explore the therapeutic potential of targeting these pathways. In conclusion, our study contributes to a deeper understanding of the metabolic landscape of PCa in Sudanese patients, emphasizing the importance of personalized approaches in cancer management.

Chiral Amino Acids Mediate Mitochondria-Dependent Apoptosis of Human Proximal Tubular Epithelial Cells Under Oxidative Stress.

Amino acids are the basic structural units of life, and their intake levels affect disease and health. In the case of renal disease, alterations in amino acid metabolism can be used not only as a clinical indicator of renal disease but also as a therapeutic strategy. However, the biological roles and molecular mechanisms of natural chiral amino acids in human proximal tubular epithelial cells (HK-2) remain unclear. In this study, cell viability assays revealed that chiral acidic amino acids (Glu and Asp) and aromatic amino acids (Trp and Phe) inhibited cell growth. The molecular mechanisms indicated that cell growth was closely related to ROS levels. Specifically, chiral Glu, Asp, Trp, and Phe induced oxidative stress and mitochondria-dependent apoptosis in HK-2 cells. This was manifested by elevated levels of intracellular ROS, 8-OHdG, and MDA, increased activities of antioxidant enzymes CAT, SOD, and GPx, decreased mitochondrial membrane potential, increased cytoplasmic Ca2+ concentration, and cell acidification. The expression levels of apoptosis-related molecules Caspase-9, Caspase-3, Cyt-C, and Bax were increased, and the expression level of anti-apoptotic molecule Bcl-2 was decreased. Moreover, L-Glu, D-Asp, L-Trp, and D-Phe exhibited a more pronounced inhibition of cell growth and elicited more substantial alterations in gene expression compared to the other configurations.

Proteomic analysis of effects of 1% atropine in myopia therapy in Guinea pigs.

Myopia is a significant global public health issue. Key interventions for managing myopia include atropine treatment, optical correction, and surgical methods. This study focused on evaluating alterations in retinal protein expression after atropine therapy for myopia. Guinea pigs were randomly divided into four groups: control (CON), monocular form-deprivation myopia (FDM), FDM with 2-week atropine treatment (FDM+ATR), and atropine-only treatment (ATR). After two weeks of FDM induction, the FDM group showed significant differences in refractive error and increased axial lengths. In comparing the retinas of myopic and normal eyes, 30 proteins were found to have increased expression, while 8 proteins showed decreased expression. Atropine-treated retinas exhibited 73 proteins with increased expression and 29 proteins with decreased expression compared to the normal eyes. A total of 11 regulated proteins overlapped between the FDM+ATR vs FDM and FDM vs CON groups. IPA analysis indicates significant alterations in amino acid metabolism, energy production, post-translational modification, small molecule biochemistry, and free radical scavenging. Our study identifies retinal protein changes in myopic guinea pigs and in guinea pigs treated with atropine after myopia. These proteins could serve as potential targets for atropine treatment of myopia.

Phytochemical S-methyl-L-cysteine sulfoxide from Brassicaceae: a key to health or a poison for bees?

Intensive agricultural practices impact the health and nutrition of pollinators like honey bees (Apis mellifera). Rapeseed (Brassica napus L.) is widely cultivated, providing diverse nutrients and phytochemicals, including S-methyl-L-cysteine sulfoxide (SMCSO). While the nutritional impact of rapeseed on bees is known, SMCSO's effects remain unexplored. We examined SMCSO and its related metabolites-3-methylthiolactic acid sulfoxide and N-acetyl-S-methyl-L-cysteine sulfoxide-analysing their seasonal fluctuations, colony variations and distribution in body parts. Our findings showed that these compounds in bee gut vary among colonies, possibly due to the dietary preferences, and are highly concentrated in bodies during the summer. They are distributed differently within bee bodies, with higher concentrations in the abdomens of foragers compared with nurses. Administration of SMCSO in a laboratory setting showed no immediate toxic effects but significantly boosted bees' antioxidant capacity. Long-term administration decreased bee body weight, particularly in the thorax and head, and altered amino acid metabolism. SMCSO is found in the nectar and pollen of rapeseed flowers and highly accumulates in rapeseed honey compared with other types of honey. This study reveals the dual impact of SMCSO on bee health, providing a basis for further ecological and physiological research to enhance bee health and colony sustainability.

Metabolomic characterization of unintentional weight loss among community-dwelling older Black and White men and women.

This study aims to understand the metabolic mechanisms of unintentional weight loss in older adults. We investigated plasma metabolite associations of subsequent weight change over 2 years in 1536 previously weight stable participants (mean age 74.6 years, 50% women, 35% Black) from the Health, Aging and Body Composition (Health ABC) Study. Multinomial logistic regressions were used to examine associations of the 442 metabolites with weight loss with/without an intention and weight gain >3% annually relative to weight stability. The metabolite associations of unintentional weight loss differed from those of intentional weight loss and weight gain. Lower levels of aromatic amino acids, phospholipids, long-chain poly-unsaturated triglycerides, and higher levels of amino acid derivatives, poly-unsaturated fatty acids, and carbohydrates were associated with higher odds of unintentional weight loss after adjusting for age, sex, race, and BMI categories. Prevalent diseases attenuated four and lower mid-thigh muscle mass and poorer appetite each attenuated 2 of 77 identified metabolite associations by >20%, respectively. Other factors (e.g., energy expenditure, diet, and medication) attenuated all associations by <20%. While 16 metabolite associations were attenuated by 20%-48% when adjusting for all these risk factors, 47 metabolite associations remained significant. Altered amino acid metabolism, impaired mitochondrial fatty acid oxidation, and inflammaging implicated by identified metabolites appear to precede unintentional weight loss in Health ABC older adults. Furthermore, these pathways seem to be associated with prevalent diseases especially diabetes, lower muscle mass, and poorer appetite.

Divergent Molecular Responses to Heavy Water in Arabidopsis thaliana Compared to Bacteria and Yeast.

Heavy water (D2O) is scarce in nature, and despite its physical similarity to water, D2O disrupts cellular function due to the isotope effect. While microbes can survive in nearly pure D2O, eukaryotes such as Arabidopsis thaliana are more sensitive and are unable to survive higher concentrations of D2O. To explore the underlying molecular mechanisms for these differences, we conducted a comparative proteomic analysis of E. coli, S. cerevisiae, and Arabidopsis after 180 min of growth in a D2O-supplemented media. Shared adaptive mechanisms across these species were identified, including changes in ribosomal protein abundances, accumulation of chaperones, and altered metabolism of polyamines and amino acids. However, Arabidopsis exhibited unique vulnerabilities, such as a muted stress response, lack of rapid activation of reactive oxygen species metabolism, and depletion of stress phytohormone abscisic acid signaling components. Experiments with mutants show that modulating the HSP70 pool composition may promote D2O resilience. Additionally, Arabidopsis rapidly incorporated deuterium into sucrose, indicating that photosynthesis facilitates deuterium intake. These findings provide valuable insights into the molecular mechanisms that dictate differential tolerance to D2O across species and lay the groundwork for further studies on the biological effects of uncommon isotopes, with potential implications for biotechnology and environmental science.

Transcriptional responses to diets without mineral phosphorus supplementation in the jejunum of two high-yielding laying hen strains

Phosphorus (P) is an essential mineral for all forms of life including laying hens, playing a crucial role in growth and efficient egg production. Recent studies suggest that current P recommendations might exceed the physiological demand, leading to unnecessarily high P excretions. This study on Lohmann Brown (LB) and Lohmann Selected Leghorn (LSL) laying hens (n=80; 10 replicates per strain, production period, and dietary group) investigates transcriptional changes in the jejunum, a critical intestinal segment for mineral absorption, in response to a diet either without (P-) or with (P+) a mineral supplement from monocalcium phosphate, administered over a 4-week period during the transition (15–19 weeks) or onset of laying (20–24 weeks). DESeq2 analysis of RNA sequencing data revealed that most differentially expressed genes (DEGs) varied between strains and age groups, with less pronounced effects from dietary mineral P content. The 19-week-old LB hens showed a stronger response to dietary mineral P removal, with transcripts affiliated with increased adaptation of the metabolism and decreased immune pathway activation. The identified pathways such as folate biosynthesis and p53 signaling, potentially link altered energy and amino acid metabolism (2-oxocarboxylic acid and arginine). Interestingly, genes involved in calcium transport (CALB1) and cellular signaling (PRKCA, STEAP4) along with tight junctions (CLDN2) were affected by complete removal of mineral P supplements, suggesting a promoted intestinal mineral uptake. Transcriptional regulation in the jejunum in response to low dietary mineral content is strain-specific when the laying phase begins, which may contribute to a physiological Ca:P ratio.

Scutellarein inhibits lung cancer growth by inducing cell apoptosis and inhibiting glutamine metabolic pathway

Ethnopharmacological relevanceScutellaria baicalensis Georgi, a widely used Chinese medicinal herb, has shown effectiveness against lung cancer. Scutellarein, a key component of Scutellaria baicalensis, also demonstrates anticancer properties in lung cancer. However, the underlying mechanisms have not yet been clarified. Aim of the studyThis study aimed to investigate the effects of scutellarein in the treatment of NSCLC and its underlying mechanisms. MethodsThis study explored the effects of scutellarein on non–small cell lung cancer (NSCLC) and its mechanisms. A Lewis lung cancer mouse model was established to assess scutellarein's anticancer activity in vivo. Additionally, the compound's effects on cell proliferation, colony formation, migration, and apoptosis were evaluated in vitro using A549 and H1299 lung cancer cells. Metabolomics analysis was conducted to identify changes in cellular metabolism due to scutellarein, while molecular docking and western blotting techniques were employed to elucidate the molecular mechanisms of its anti-lung cancer effects. ResultsScutellarein significantly inhibited lung cancer xenograft tumor growth. In vitro studies showed that scutellarein suppressed migration and colony formation in A549 and H1299 cells, induced cell cycle arrest, and triggered cell apoptosis. Notably, scutellarein profoundly altered amino acid metabolism, particularly affecting glutamine metabolites. It affected key glutamine transporters ASCT2 and LAT1, as well as glutaminase GLS1, leading to their reduced expression. ConclusionScutellarein effectively inhibits lung cancer growth both in vivo and in vitro by inducing cell apoptosis and downregulating the glutamine metabolic pathway.

Branched-chain amino acid catabolism promotes ovarian cancer cell proliferation via phosphorylation of mTOR.

Ovarian cancer is the sixth leading cause of cancer-related mortality among individuals with ovaries, and high-grade serous ovarian cancer (HGSOC) is the most common and lethal subtype. Characterized by a distinct and aggressive metastatic pattern, HGSOC can originate in the fallopian tube with the transformation of fallopian tube epithelial (FTE) cells, which metastasize to the ovary and subsequently to the omentum and peritoneal cavity. The omentum is a privileged metastatic site, and the metabolic exchange underlying omental metastasis could provide enzyme or receptor targets to block spread. In this study, we adapted a mass spectrometry imaging (MSI) protocol to investigate spatial location of 3D cocultures of tumorigenic FTE cells when grown in proximity to murine omental explants as a model of early metastatic colonization. Our analysis revealed several altered metabolites in tumorigenic FTE/omentum cocultures, namely changes in branched-chain amino acids (BCAA), including valine. We quantified the heightened consumption of valine, other BCAAs, and other amino acid-derived metabolites in omental cocultures using LC-MS assays. Our analysis revealed that metabolite concentrations when monitored with MSI from cell culture media in living culture systems have notable considerations for how MSI data may produce signatures that induce ionization suppression. Supplementation with valine enhanced proliferation and mTOR signaling in tumorigenic FTE cells, suggesting the potential of BCAA's as a nutrient utilized by tumor cells during omental colonization and a possible target for metastasis.

Nutritional status and extended metabolic screening in Egyptian children with uncomplicated type 1 diabetes

Nutritional status assessment, including amino acids, carnitine, and acylcarnitine profile, is an important component of diabetes care management, influencing growth and metabolic regulation. A designed case–control research included 100 Egyptian participants (50 T1DM and 50 healthy controls) aged 6 to 18 years old. The participants' nutritional status was assessed using the Body Mass Index (BMI) Z-score. Extended metabolic screening (EMS) was performed using a high-performance liquid chromatography-electrospray ionization-mass spectroscopy system to evaluate the levels of 14 amino acids, free carnitine, and 27 carnitine esters. T1DM children had considerably lower anthropometric Z-scores than the control group, with 16% undernutrition and 32% short stature. Total aromatic amino acids, phenylalanine, phenylalanine/tyrosine ratio, proline, arginine, leucine, isoleucine, free carnitine, and carnitine esters levels were considerably lower in the diabetic group, suggesting an altered amino acid and carnitine metabolism in type 1 diabetes. BMI Z-score showed a significant positive correlation with Leucine, Isoleucine, Phenylalanine, Citrulline, Tyrosine, Arginine, Proline, free carnitine, and some carnitine esters (Acetylcarnitine, Hydroxy-Isovalerylcarnitine, Hexanoylcarnitine, Methylglutarylcarnitine, Dodecanoylcarnitine, Tetradecanoylcarnitine, and Hexadecanoylcarnitine). HbA1c% had a significant negative correlation with Total aromatic amino acids, Branched-chain amino acid/Total aromatic amino acids ratio, Glutamic Acid, Citrulline, Tyrosine, Arginine, Proline, and certain carnitine esters (Propionylcarnitine, Methylglutarylcarnitine, Decanoylcarnitine, Octadecanoylcarnitine and Octadecenoylcarnitine), suggest that dysregulated amino acid and carnitine metabolism may be negatively affect the glycaemic control in children with TIDM. In conclusion, regular nutritional assessments including EMS of T1DM patients are critical in terms of diet quality and protein content for improved growth and glycemic management.

Application of Eight Machine Learning Algorithms in the Establishment of Infertility and Pregnancy Diagnostic Models: A Comprehensive Analysis of Amino Acid and Carnitine Metabolism.

To explore the effects of altered amino acids (AAs) and the carnitine metabolism in non-pregnant women with infertility (NPWI), pregnant women without infertility (PWI) and infertility-treated pregnant women (ITPW) compared with non-pregnant women (NPW, control), and develop more efficient models for the diagnosis of infertility and pregnancy, 496 samples were evaluated for levels of 21 AAs and 55 carnitines using targeted high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). Three methods were used to screen the biomarkers for modeling, with eight algorithms used to build and validate the model. The ROC, sensitivity, specificity, and accuracy of the infertility diagnosis training model were higher than 0.956, 82.89, 66.64, and 82.57%, respectively, whereas those of the validated model were higher than 0.896, 77.67, 69.72, and 83.38%, respectively. The ROC, sensitivity, specificity, and accuracy of the pregnancy diagnosis training model were >0.994, 96.23, 97.79, and 97.69%, respectively, whereas those of the validated model were >0.572, 96.39, 93.03, and 94.71%, respectively. Our findings indicate that pregnancy may alter the AA and carnitine metabolism in women with infertility to match the internal environment of PWI. The developed model demonstrated good performance and high sensitivity for facilitating infertility and pregnancy diagnosis.

Maternal Undernutrition Affects Fetal Thymus DNA Methylation, Gene Expression, and, Thereby, Metabolism and Immunopoiesis in Wagyu (Japanese Black) Cattle.

We aimed to determine the effects of maternal nutrient restriction (MNR) on the DNA methylation and gene expression patterns associated with metabolism and immunopoiesis in the thymuses of fetal Wagyu cattle. Pregnant cows were allocated to two groups: a low-nutrition (LN; 60% nutritional requirement; n = 5) and a high-nutrition (HN; 120% nutritional requirement, n = 6) group, until 8.5 months of gestation. Whole-genome bisulfite sequencing (WGBS) and RNA sequencing were used to analyze DNA methylation and gene expression, while capillary electrophoresis-Fourier transform mass spectrometry assessed the metabolome. WGBS identified 4566 hypomethylated and 4303 hypermethylated genes in the LN group, with the intergenic regions most frequently being methylated. Pathway analysis linked hypoDMGs to Ras signaling, while hyperDMGs were associated with Hippo signaling. RNA sequencing found 94 differentially expressed genes (66 upregulated, 28 downregulated) in the LN group. The upregulated genes were tied to metabolic pathways and oxidative phosphorylation; the downregulated genes were linked to natural killer cell cytotoxicity. Key overlapping genes (GRIA1, CACNA1D, SCL25A4) were involved in cAMP signaling. The metabolomic analysis indicated an altered amino acid metabolism in the MNR fetuses. These findings suggest that MNR affects DNA methylation, gene expression, and the amino acid metabolism, impacting immune system regulation during fetal thymus development in Wagyu cattle.

Metabolomic analysis reveals altered amino acid metabolism and mechanisms underlying Eimeria infection in laying hens

Avian coccidiosis, caused by Eimeria spp, is a devastating disease in laying hens. Previous studies have suggested that amino acids may be involved in Eimeria infection of broiler chickens. However, their metabolic features in laying hens, as well as the effect of multiple Eimeria species challenges on poultry hosts have not been elucidated yet. Here, a targeted metabolomics approach was employed to identify altered amino acid metabolism and mechanisms in laying hens with multiple Eimeria species challenges. Laying hens, Hy-Line W-36 aged 25 wk, were randomly assigned to a control group and groups inoculated with varying levels of mixed Eimeria species (E. maxima, E. tenella, and E. acervulina). Serum samples from each group were collected at 6 d and 14 d of postinoculation (6 and 14 DPI) for metabolite profiling. Metabolomic analysis revealed notable metabolic variations between control and infected groups, especially at 6 DPI stage. Varying levels of Eimeria dosages did not show a significant metabolic difference, and metabolites were sensitive to low-level infection. With statistical analysis, differentially expressed compounds (3-methylhistidine, alanine, aspartate, lysine, asparagine, methionine, ornithine, and tryptophan) were selected, and their metabolic network was identified by pathway enrichment analysis. In the network, the lysine biosynthesis pathway was upregulated, while the arginine and proline metabolic pathway was downregulated under infection. Other pathways showed complex patterns of metabolic relationships. Based on the results, biological implications of metabolic changes were elucidated and discussed. Last, the results were further confirmed with our previous study (phenotype and gene expression results) using the same set of samples. Our finding provides in-depth information on altered amino acid metabolism and mechanisms in laying hens upon multiple Eimeria species infection.

Integrated analysis of transcriptome, proteome and non-targeted metabolome for exploring the mechanism of selenium biotransformation in Pichia kudriavzevii

Pichia kudriavzevii could resist high concentrations of sodium selenite and efficiently biotransform over 80% of the absorbed selenium. However, the specific molecular mechanisms underlying this biotransformation remain unclear. This study aimed to investigate the mechanism of selenium biotransformation focusing on selenium transport, detoxification, reduction, and the formation of organic selenium compounds through a comprehensive approach combining transcriptomic, proteomic, and non-targeted metabolomic analyze. Results showed that the JEN1 gene was responsible for selenium transport, while the upregulation of cysJ, CYSK, TRXB1 and sat genes as well as the involvement of glutathione, are crucial for the accumulation of organic selenium. Furthermore, GSTY2, TRXB1 and GPX3 were pivotal genes in Se(IV) reduction and their corresponding proteins were key proteins. Additionally, the enhanced expression of genes related to antioxidant enzymes (GSTY2, TRXB1, and GPX3), ABC transports, heat shock proteins and antioxidant enzymes proteins (GSTY2, TRXB1, and GPX3) collectively contributed to selenium tolerance, detoxification and protection against oxidative damage. GO and KEGG analysis highlighted alterations in amino acid metabolism, carbohydrate metabolism, and energy metabolism in the selenium biotransformation process. These findings provide novel insight into the mechanisms of selenium biotransformation in P. kudriavzevii and its application in the fields of the food industry.

Chloroplastic ascorbate modifies plant metabolism and may act as a metabolite signal regardless of oxidative stress.

Ascorbate is a major plant metabolite that plays crucial roles in various processes, from reactive oxygen scavenging to epigenetic regulation. However, to what extent and how ascorbate modulates metabolism is largely unknown. We investigated the consequences of chloroplastic and total cellular ascorbate-deficiencies by studying chloroplastic ascorbate-transporter mutant lines lacking PHOSPHATE TRANSPORTER 4; 4 (PHT4; 4) , and the ascorbate-deficient vtc2-4 mutant of Arabidopsis (Arabidopsis thaliana). Under regular growth conditions, both ascorbate deficiencies caused minor alterations in photosynthesis, with no apparent signs of oxidative damage. In contrast, metabolomics analysis revealed global and largely overlapping alterations in the metabolome profiles of both ascorbate-deficiency mutants, suggesting that chloroplastic ascorbate modulates plant metabolism. We observed significant alterations in amino acid metabolism, particularly in arginine metabolism, activation of nucleotide salvage pathways, and changes in secondary metabolism. In addition, proteome-wide analysis of thermostability revealed that ascorbate may interact with enzymes involved in arginine metabolism, the Calvin-Benson cycle, and several photosynthetic electron transport components. Overall, our results suggest that, independently of oxidative stress, chloroplastic ascorbate modulates the activity of diverse metabolic pathways in vascular plants and may act as an internal metabolic signal.