Search Results (88)

Vaccination remains the core strategy for the prevention and control of Newcastle disease (ND). The inherent thermosensitivity of traditional Newcastle disease virus (NDV) vaccines imposes major limitations on their transportation, storage, and field application. To address these challenges, a novel liquid, thermostable, live ND vaccine was developed in the present study. Firstly, Tris/HCl buffer at near-neutral pH was identified as the optimal basic buffer system. On this basis, further screening and formulation optimization of vaccine stabilizers were conducted, and NDV strains with excellent thermal stability were used to verify the stability-conferring properties of the developed stabilizer. The results showed that the formulation composed of 0.5% gelatin, 4% trehalose, 0.1% L-glutamic acid, and 0.5% thiourea was confirmed as the optimal stabilizer for ND liquid vaccines. This formulation maintained the stable storage of the tested NDV for 12 months at 4 °C and exhibited promising stability for 30 days at 25 °C, marking a significant advancement toward development thermostable NDV vaccines that are independent of a continuous cold chain. More importantly, the liquid vaccine stored at 4 °C for 12 months still induced high levels of NDV-specific antibodies in specific pathogen-free chicks and provided 100% protective efficacy against challenge with virulent NDV. In conclusion, the liquid vaccine stabilizer developed in this study not only significantly enhanced the thermostability of the vaccine but also effectively maintained its immunogenicity, thereby providing an important theoretical basis for the research and development of liquid ND vaccines. Full article

The microbial production of 1,5-pentanediol (1,5-PDO), a versatile platform chemical with extensive industrial applications, remains limited by suboptimal fermentation titers and incomplete understanding of metabolic bottlenecks. To address these challenges, this study employed comparative transcriptomics to systematically identify novel genetic targets capable of enhancing 1,5-PDO biosynthesis in engineered Escherichia coli. Transcriptomic profiling of the 1,5-PDO-producing strain relative to the parental E. coli W3110, conducted at both exponential (24 h) and stationary (96 h) growth phases, revealed 1384 significantly differentially expressed genes, including 851 upregulated and 533 downregulated genes. From these, 20 candidate metabolic genes associated with 1,5-PDO synthesis were selected for functional validation through plasmid-based overexpression or CRISPR interference (CRISPRi)-mediated repression. Reverse engineering confirmed that overexpression of fecA (encoding an iron(III)-citrate transporter) and deletion of gadA (encoding glutamate decarboxylase) significantly enhanced 1,5-PDO production. Subsequent chromosomal integration of fecA at the neutral ilvG locus and deletion of gadA generated the optimized strain S7, which achieved a 1,5-PDO titer of 1.7 g/L in shake flask cultures, representing a 13.3% increase over the parental strain, with a concomitant 50% improvement in glucose yield (0.18 mol/mol). In fed-batch fermentation at the 5 L bioreactor scale, strain S7 attained a titer of 12.45 g/L and a glucose yield of 0.26 mol/mol, marking a 15.6% enhancement in carbon conversion efficiency relative to the parental strain (0.225 mol/mol), while concurrently improving biomass accumulation by 7.6%. These findings demonstrate that transcriptomics-guided reverse engineering constitutes an effective strategy for elucidating nonobvious metabolic determinants and optimizing microbial cell factories for efficient 1,5-PDO production. The identification of fecA and gadA as beneficial targets provides valuable insights into the metabolic rewiring underlying enhanced 1,5-PDO biosynthesis and establishes a foundation for further strain improvement through systems metabolic engineering. Full article

Epilepsy is a neurological disorder characterized by a long-lasting predisposition to recurrently generate unprovoked seizures. Epilepsy affects over 70 million people worldwide, with approximately one-third suffering from pharmacoresistant seizures. Currently, the clinical antiseizure drugs lack efficacy in preventing epileptogenesis. Adenosine, as an endogenous anticonvulsant, inhibits the development of epilepsy via interaction with the molecular epileptogenic network on several levels: (i) Activation of A1 receptor inhibits glutamate release via presynaptic inhibition, and hyperpolarizes the synaptic potentials in postsynaptic neurons. (ii) The A2A receptor on astrocytes interacts with astroglial glutamate transporter GLT-1, controlling glial glutamate homeostasis. (iii) Activation of the A3 receptor inhibits GABA transporter type 1-mediated GABA uptake. (iv) Adenosine kinase (ADK) is highlighted as a pathological hallmark of epilepsy, with its distinct isoforms driving different mechanisms. The cytoplasmic short isoform (ADK-S) in astrocytes controls extracellular adenosine and receptor-mediated pathways, whereas the nuclear long isoform (ADK-L) in astrocytes and specific neurons regulates epigenetic mechanisms without relying on adenosine receptors. Collectively, this review clarifies the adenosine system’s critical regulatory role in the epileptogenic network, highlights adenosine receptors and ADK isoforms as promising therapeutic targets for epilepsy, and provides a theoretical basis for developing novel disease-modifying therapies for pharmacoresistant epilepsy while laying a foundation for subsequent preclinical and clinical translation. Full article

Interferon-γ (IFNγ), a key inflammatory cytokine that orchestrates immune responses, also emerges as a regulator of cellular metabolism; however, in alveolar epithelial cells its impact on amino acid homeostasis remains poorly defined. Here, we investigated the effects of IFNγ on intracellular amino acid content and transmembrane transport in human alveolar epithelial A549 cells, focusing on the contribution of the JAK/STAT/IRF1 signaling axis. To this end, A549 WT and IRF1 knockout (IRF1 KO) cells were used to investigate IRF1 contribution, and baricitinib to evaluate the role of the JAK/STAT pathway. HPLC analysis reveals that in WT, but not in IRF1 KO cells, IFNγ markedly increases the intracellular concentration of many amino acids, including glutamine, glutamate, and several neutral and cationic amino acids, without affecting the cell volume, thus indicating true metabolic accumulation. The measurement of the transmembrane uptake of specific radiolabeled amino acids demonstrates a concomitant increase in transport Systems ASC, A, L, and y⁺ activity; an upregulation of the related transporters ASCT2, SNAT2, LAT1, and CAT1 has also been observed by means of qPCR analysis. Moreover, conditioned medium from SARS-CoV-2 spike-activated macrophages recapitulates IFNγ-driven amino acid remodeling in a JAK/STAT/IRF1-dependent manner. Overall, our findings identify IFNγ as a potent regulator of intracellular amino acid availability in alveolar epithelial cells through the modulation of the activity of membrane transporters. The observed IFNγ-reprogramming is IRF1 dependent, ascribing a crucial role to this transcription factor in linking inflammation and amino acid metabolism. Full article

Background/Objectives: Semen Ziziphi Spinosae (SZS), a medicinal and edible traditional Chinese herb, has been widely used to treat insomnia. As critical regulators of the central nervous system, astrocytes play a pivotal role in maintaining sleep homeostasis. However, the mechanisms by which SZS modulates astrocytic function to improve sleep remain unclear. Methods: In this study, we employed an integrated transcriptomics and metabolomics approach to investigate the protective effects of SZS extract against lipopolysaccharide (LPS)-induced inflammatory injury and metabolic dysfunction in astrocytes. Results: Transcriptomic analysis revealed that SZS ameliorates cellular damage (including apoptosis, autophagy, and cell cycle dysregulation) through a FOXO3-centric signaling network. Concurrently, SZS restored cellular energy metabolism by increasing ATP production and reducing Ca²⁺ overload, thereby activating the AMPK signaling pathway to support normal astrocytic function. Metabolomic profiling further demonstrated that SZS-mediated restoration of energy homeostasis sustains ABC transporter activity, which in turn modulates neurotransmitter (serotonin, L-glutamic acid, adenosine), metabolic mediators (leukotrienes, palmitoylethanolamide, succinic acid), and nucleotide (uridine 5′-diphosphate). These coordinated changes normalized GABAergic synapse activity and neuroactive ligand receptor interactions, ultimately resolving neural metabolic network disturbances. Conclusions: Our findings elucidate a novel FOXO3-energy metabolism-ABC transporter axis through which SZS extract attenuates neuroinflammation and metabolic dysfunction in astrocytes and exerts sleep-promoting and neuroprotective effects. This study provides a scientific foundation for understanding the modern pharmacological mechanisms of traditional Chinese medicine in insomnia treatment, highlighting astrocytic regulation as a potential therapeutic target. Full article

The aim of the present study is to evaluate the impact of chromium (Cr) supplementation on glucose and lipid metabolism in breast muscle in broilers under heat stress. A total of 220 day-old broiler chicks were reared in cages. At 29 days old, 180 birds were randomly assigned to three treatments (0, 400, and 800 µg Cr/kg, as chromium picolinate) and transferred to climate chambers (31 ± 1 °C, 60 ± 7% humidity) for 14 days. Growth performance, carcass traits, serum biochemical indices, fasting glucose and insulin, homeostasis model assessment of insulin resistance (HOMA-IR), as well as muscle metabolomic profiles and gene expression related to energy and lipid metabolism were analyzed. The results showed that, compared with the heat stress group, the groups supplemented with 400 and 800 µg Cr/kg showed higher dry matter intake and average daily gain, breast muscle ratio, and lower feed conversion ratio and abdominal fat ratio; chickens supplemented with 400 and 800 µg Cr/kg showed significantly lower serum corticosterone (CORT), free fatty acids, and cholesterol levels compared with the heat stress (HS) group (p < 0.05). Fasting blood glucose and HOMA-IR were also significantly reduced, while fasting insulin was significantly increased in the Cr-supplemented groups (p < 0.05). Metabolomic analysis revealed that Cr supplementation regulated lipid and amino acid metabolism by altering key metabolites such as citric acid, L-glutamine, and L-proline, and modulating pathways including alanine, aspartate, and glutamate metabolism, and glycerophospholipid metabolism. Furthermore, Cr supplementation significantly upregulated the expression of Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1 α (PGC-1α), ATP Binding Cassette Subfamily A Member 1 (ABCA1), Peroxisome Proliferator-Activated Receptor α (PPARα), and ATP Binding Cassette Subfamily G Member 1 (ABCG1) in both the hepatic and muscle tissue. This paper suggested that chromium supplementation may enhance energy metabolism and lipid transport like the findings of our study suggested. Full article

Background/Objectives: Glutamatergic neurotransmission is essential for the normal functioning of the retina. Photoreceptor to bipolar and bipolar to ganglion cell signaling is mediated by L-glutamate, which is stored in and released from vesicular glutamate transporter 1 (VGLUT1) containing synaptic vesicles. VGLUT1 is expressed postnatally, P2 onwards, and is required for the glutamatergic retinal wave observed between P10 and P12 in the developing mouse retina. P9–P13 postnatal age is critical for retinal development as VGLUT1 expressing ribbon synapses activate in the outer and inner plexiform layers, and rod/cone mediated visual signaling commences in that period. Although it has been hypothesized that glutamatergic extrinsic signaling drives cell cycle exit and initiates cellular differentiation in the developing retina, it is not clear whether intracellular, synaptic, or extrasynaptic vesicular glutamate release contributes to this process. Recent studies have attempted to decipher VGLUT’s role in retinal development. Here, we investigate the potential effect of genetic loss of VGLUT1 on early postnatal histogenesis and development of retinal neural circuitry. Methods: We employed immunohistochemistry and electrophysiology to ascertain the density of glutamatergic, cholinergic, and dopaminergic cells, spontaneous retinal activity, and light responses in VGLUT1 null retina, and contrasted them with wildtype (WT) and melanopsin null retina. Results: We have demonstrated here that VGLUT1 null retina shows signs of age dependent retinal degeneration, similar to other transgenic mice models with dysfunctional photoreceptor to bipolar cell synapses. The loss of VGLUT1 specifically alters glutamatergic cell density and morphological maturation of retinal ganglion cells. Moreover, VGLUT2 expression is lost in the majority of VGLUT2 cones in the absence of VGLUT1 coexpression, except when VGLUT2 coexpresses transiently with VGLUT3 in these cones, or when VGLUT1 null mice are dark reared. Conclusions: We present the first evidence that synaptic or extrasynaptic postnatal glutamate release from VGLUT1 containing vesicles impacts histogenesis of glutamatergic cells, pruning of retinal ganglion cell dendrites and VGLUT2 expression in cones. Full article

Anesthesia has emerged as a critical strategy for maintaining fish viability during transport, with natural anesthetics gaining increasing attention in recent research. The active ingredients in Laurus nobilis L. have antioxidant effects and reduce cell apoptosis. Studies have shown that they can upregulate expression of Nrf2 in mitochondrial biosynthetic factors. This study aimed to investigate the effects of laurel (Laurus nobilis) essential oil on oxidative stress and apoptosis mechanisms during the live transport of hybrid grouper (Epinephelus fuscoguttatus♀ × E. lanceolatus♂). The addition of laurel essential oil during transport activated the Nrf2-Keap1 antioxidant pathway, resulting in up-regulated expression of catalase (cat) and superoxide dismutase (sod) genes. This led to increased enzymatic activity and reduced levels of oxidative stress markers. The mitigation of oxidative stress contributed to physiological stability by downregulating apoptotic gene expression (Bax, Caspase 8), reducing gill and liver tissue damage, and lowering the activity of hepatocyte damage markers aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Metabolomic analysis revealed several key metabolic pathways affected during transport, with the FoxO signaling pathway demonstrating the most significant impact. Within this pathway, reduced glutamate levels appeared to inhibit apoptosis, while decreased ADP and AMP levels potentially influenced antioxidant capacity. The addition of laurel essential oil to transport water proved beneficial in reducing biochemical markers of stress responses in hybrid grouper during keep live transport. Full article

Background/Objectives: Chronic manganese (Mn) exposure is a recognized environmental contributor to Parkinsonian syndromes, including Mn-induced Parkinsonism (MnIP). This study aimed to evaluate whole-blood Mn levels and investigate disease/exposure-status-related alterations in metabolomic and lipidomic profiles. Methods: A case–control study (N = 97) was conducted in Brescia, Italy, stratifying participants by Parkinsonism diagnosis and residential Mn exposure. Whole-blood Mn was quantified using ICP-MS. Untargeted metabolomic and lipidomic profiling was conducted using LC-MS. Statistical analyses included Mann–Whitney U tests, conditional logistic regression, ANCOVA, and pathway analysis. Results: Whole-blood Mn levels were significantly elevated in Parkinsonism cases vs. controls (median: 1.55 µg/dL [IQR: 0.75] vs. 1.02 µg/dL [IQR: 0.37]; p = 0.001), with Mn associated with increased odds of Parkinsonism (OR = 2.42, 95% CI: 1.13–5.17; p = 0.022). The disease effect metabolites included 3-sulfoxy-L-tyrosine (β = 1.12), formiminoglutamic acid (β = 0.99), and glyoxylic acid (β = 0.83); all FDR p < 0.001. The exposure effect was associated with elevated glycocholic acid (β = 0.51; FDR p = 0.006) and disrupted butanoate (Impact = 0.03; p = 0.004) and glutamate metabolism (p = 0.03). Additionally, SLC-mediated transmembrane transport was enriched (p = 0.003). The interaction effect identified palmitelaidic acid (β = 0.30; FDR p < 0.001), vitamin B6 metabolism (Impact = 0.08; p = 0.03), and glucose homeostasis pathways. In lipidomics, triacylglycerols and phosphatidylethanolamines were associated with the disease effect (e.g., TG(16:0_10:0_18:1), β = 0.79; FDR p < 0.01). Ferroptosis and endocannabinoid signaling were enriched in both disease and interaction effects, while sphingolipid metabolism was specific to the interaction effect. Conclusions: Mn exposure and Parkinsonism are associated with distinct metabolic and lipidomic perturbations. These findings support the utility of omics in identifying environmentally linked Parkinsonism biomarkers and mechanisms. Full article

Chinese perch (Siniperca chuatsi), an economically important freshwater fish in China, faces ammonia nitrogen stress under high-density aquaculture. This study investigated chronic ammonia nitrogen exposure effects on juvenile fish (95 ± 5 g) to establish safe concentration. Acute toxicity tests revealed a 96 h-LC₅₀ of 12.91 mg/L ammonia nitrogen, with a safe concentration of 1.29 mg/L ammonia nitrogen (non-ionic ammonia: 0.097 mg/L). In 28-day chronic experiments with ammonia nitrogen levels at 0, 0.61, 1.29, and 2.58 mg/L, ammonia nitrogen induced hepatic oxidative stress, with total superoxide dismutase, catalase, and glutathione peroxidase activities and malondialdehyde content increasing proportionally to ammonia nitrogen concentration initially but declining over time. Concurrently, gill Na⁺-K⁺-ATPase activity was significantly suppressed, while the gene expression of ammonia transporters (rhag, rhbg, and rhcg) exhibited ammonia nitrogen concentration-dependent upregulation, inversely correlated with the exposure duration. Histological gill damage intensified at higher concentrations. Hepatic ammonia detoxification enzymes activities (asparagine synthase, glutamine synthetase, and glutamate dehydrogenase) and glutamine accumulation increased with ammonia nitrogen levels, aligning with gene expression trends, though enzyme activity diminished over time. Serum alanine aminotransferase and aspartate aminotransferase activities and their gene expressions rose with ammonia nitrogen levels, while total protein declined. These findings demonstrate that chronic ammonia nitrogen stress disrupts antioxidant capacity, osmoregulation, and nitrogen metabolism, compelling Chinese perch to mitigate toxicity via glutamine synthesis. To ensure sustainable aquaculture, ammonia nitrogen levels should remain below 1.29 mg/L under adequate dissolved oxygen conditions. Full article

In the absence of fully effective therapies and preventive strategies against the development of urosepsis, a deeper understanding of the virulence mechanisms of Uropathogenic Escherichia coli (UPEC) strains is needed. UPEC strains employ a wide range of virulence factors (VFs) to persist in the urinary tract and bloodstream. UPEC strains were isolated from patients with sepsis and a control group without sepsis. PCR was used to detect 36 genes encoding various groups of virulence and fitness factors. Profiling of both intracellular and extracellular bacterial proteins was also included in our approach. Bacterial metabolites were identified and quantified using GC-MS and LC-MS techniques. The UpaG autotransporter, a trimeric E. coli AT adhesin, was significantly more prevalent in urosepsis strains (p = 0.00001). Iron uptake via aerobactin and the Iha protein also appeared to be predictive of urosepsis (p = 0.03 and p = 0.002, respectively). While some studies suggest an association between S fimbriae and the risk of urosepsis, we observed no such correlation (p = 0.0001). Proteomic and metabolomic analyses indicated that elevated levels of bacterial citrate, malate, coenzyme Q10, pectinesterase (YbhC), and glutamate transport proteins, as well as the regulators PhoP two-component system, CpxR two-component system, Nitrate/nitrite response regulator protein NarL, and the Ferrienterobactin receptor FepA, may play a role in sepsis. These genetic biomarkers, proteins, and metabolites derived from UPEC could potentially serve as indicators for assessing the risk of developing sepsis. Full article

6-PPD quinone (6-PPDQ) is widely distributed in environments. In Caenorhabditis elegans, we first examined the effects of 6-PPDQ on glutamate synthesis and receptor function by analyzing glutamate content, related gene expression, and phenotypes after RNAi of these genes. Moreover, we performed glutamate treatment after 6-PPDQ exposure to determine the potential pharmacological effects of glutamate against 6-PPDQ toxicity. After exposure, the glutamate content was reduced by 0.1–10 μg/L 6-PPDQ, which was due to decreased expression of W07E1.1, glna-1/2/3, and alh-6 governing glutamate synthesis from α-ketoglutarate, glutamine, and proline. RNAi of W07E1.1, glna-1/2/3, and alh-6 decreased glutamate content in 6-PPDQ-exposed nematodes, and caused susceptibility to 6-PPDQ toxicity. Among glutamate transporter genes, glt-1 expression was decreased by 0.1–10 μg/L 6-PPDQ. Moreover, 0.1–10 μg/L 6-PPDQ decreased glutamate receptor genes (glr-1, glr-2, and glr-4), and their expression was decreased by RNAi of W07E1.1, glna-1/2/3, alh-6, and glt-1. RNAi of these receptor genes resulted in susceptibility to 6-PPDQ toxicity, and daf-7, jnk-1, and dbl-1 were identified as targets of neuronal glr-1, glr-2, and glr-4. Furthermore, 5 mM glutamate suppressed 6-PPDQ toxicity and increased expression of glr-1, glr-2, and glr-4. Our results demonstrated the risk of 6-PPDQ exposure in disrupting glutamate synthesis and affecting function of glutamate receptors, which was related to 6-PPDQ toxicity induction. Full article

Salt stress poses a significant threat to crop growth. While brassinolide (BR) has been shown to alleviate its adverse effects and modulate plant development, the precise mechanism underlying BR-induced salt tolerance in rice remains unclear. In this study, the Chaoyouqianhao and Huanghuazhan rice varieties were employed to investigate the effects of BR seed soaking on the seedling phenotype, physiology, transcriptome, and metabolome under salt stress. The results demonstrated that BR treatment significantly enhanced rice plant height, root length, biomass, and antioxidant enzyme activities, while reducing leaf membrane damage, promoting ion homeostasis, and improving the photosynthetic capacity and salt tolerance. The transcriptome analysis revealed that BR regulated the expression of 1042 and 826 genes linked to antioxidant activity, ion homeostasis, photosynthesis, and lipid metabolism under salt stress. These included genes involved in Na⁺ efflux (OsNCED2, OsHKT2;1, and OsHKT1;1), photosynthetic electron transport (OsFd5 and OsFdC1), photosystem II (OsPsbR1, OsPsbR2, and OsPsbP), and CO₂ fixation. The metabolomic analysis identified 91 and 57 metabolite alterations induced by BR, primarily linked to amino acid, flavonoid, and lipid metabolism, with notable increases in antioxidant metabolites such as lignanoside, isorhamnetin, and L-glutamic acid. The integrated analysis highlighted the pivotal roles of 12-OPDA in α-linolenic acid metabolism and genes related to lipid metabolism, JA metabolism, and JA signal transduction in BR-mediated salt tolerance. Full article

Background/Objectives: Alzheimer’s disease (AD) is the most common type of dementia, characterized by complex processes such as neuro-inflammation, oxidative damage, synaptic loss, and neuronal death. Carotenoids are among the potential therapeutic molecules that have attracted attention due to their neuroprotective properties, but their efficacy is limited mainly by their capacity to cross the blood–brain barrier (BBB). Results: The results showed that T. chuii extracts could protect neuronal cells from neurotoxic damage, especially against L-glutamate and H₂O₂. Moreover, the BBB permeability and the intestinal transport analyses revealed that fucoxanthinol, crocoxanthin, diatoxanthin, neoxanthin, violaxanthin, and prasinoxanthin have diverse permeabilities depending on the incubation time and the cell model used. Fucoxanthinol was the carotenoid with the highest and similar permeability in HBMEC cells (4.41%, 5.13%, and 18.94% at 2, 4, and 24 h, respectively) and Caco-2 cells (7.01%, 8.63%, and 18.36% at the same times), while crocoxanthin, diatoxanthin, and neoxanthin showed different kinetics. Methods: The neuroprotective potential of two extracts obtained from Tetraselmis chuii microalga were evaluated against Aβ1-42-, L-glutamate-, and H₂O₂-induced toxicities in SH-SY5Y cells. In addition, the BBB permeability and the intestinal transepithelial transport of the main carotenoids present in the extracts were evaluated and compared using two cell culture models, HBMEC and Caco-2 cells. For that aim, the transport of the bioactive molecules across the barriers was evaluated using UHPLC-q-TOF-MS after 2, 4, and 24 h of incubation. Conclusions: These findings indicate that T. chuii is a promising natural source of bioactive compounds to develop functional foods against neurodegenerative diseases. Full article