Search Results (491)

This study was conducted to evaluate the effect of rumen-protected γ-aminobutyric acid (GABA) supplementation on milk productivity of lactating Holstein cows. Eighteen Holstein dairy cows (mean parity, 2.2 ± 1.0 year; mean milk yield, 34.3 ± 5.5 kg) were selected in a commercial dairy farm for the experiment. The experiment was conducted from 17 July 2024 to 11 September 2024 (56 days). Generally, THI 72 is set as a threshold since the productivity of Holstein cows starts to decrease. Animals were exposed to heat stress conditions (THI ≥ 72) during the experimental period. The basal diet was fed as a total mixed ration (TMR), and GABA was top-dressed onto the TMR. The treatments were basal diet (Control), basal diet supplemented with rumen-protected GABA 3 g/d (Treatment 1), and basal diet supplemented with rumen-protected GABA 6 g/d (Treatment 2) as a completely randomized design. Statistical significance was compared between the control and GABA treatment groups using the method of repeated measurement. Increased levels of rumen-protected GABA supplementation tended to mitigate the decline in milk yield associated with heat stress (p = 0.083). Milk fat content in the GABA supplementation groups was significantly greater than that in the control group (p = 0.036). Milk lactose content was significantly increased by GABA supplementation (p = 0.017). Blood metabolic profiles and cortisol did not differ significantly between the control and GABA supplementation groups. Activities in the GABA supplementation groups were significantly greater than those in the control group (p < 0.05). Rest and rumination times in the GABA supplementation group were significantly lower than those in the control group (p < 0.05). These results suggest that rumen-protected GABA can be a practical nutritional intervention for minimizing productivity losses in Holstein cows during periods of elevated ambient temperature. Full article

Excitable neurons are intrinsically capable of firing action potentials (AP), yet a state of hyperexcitability is prevented in the central nervous system by powerful GABAergic inhibition. For this inhibition to be effective, it must occur before excitatory signals can initiate runaway activity, implying the existence of a proactive control system. To test for such proactive inhibition, we used Ca²⁺ imaging and patch-clamp recording to measure how hippocampal neurons respond to depolarization and glutamatergic agonists. In mature hippocampal cultures (14 days in vitro (DIV)) and acute brain slices from two-month-old rats, neurons exhibited non-simultaneous responses to various excitatory stimuli, including KCl, NH₄Cl, forskolin, domoic acid, and glutamate. We observed that the Ca²⁺ rise occurred significantly earlier in GABAergic neurons than in glutamatergic neurons. This delay in glutamatergic neurons was abolished by GABA(A) receptor inhibitors, suggesting a mechanism of preliminary γ-aminobutyric acid (GABA) release. We further found that these early-responding GABAergic neurons express calcium-permeable kainate and AMPA receptors (CP-KARs and CP-AMPARs). Application of domoic acid induced an immediate Ca²⁺ increase in neurons expressing these receptors, but a delayed response in others. Crucially, when domoic acid was applied in the presence of the AMPA receptor inhibitors NBQX or GYKI-52466, the response delay in glutamatergic neurons was significantly prolonged. This confirms that CP-KARs on GABAergic neurons are responsible for the delayed excitation of glutamatergic neurons. In hippocampal slices from two-month-old rats, depolarization with 50 mM KCl revealed two distinct neuronal populations based on their calcium dynamics: a majority group (presumably glutamatergic) exhibited fluctuating Ca²⁺ signals, while a minority (presumably GABAergic) showed a steady, advancing increase in [Ca²⁺]i. This distinction was reinforced by the application of domoic acid. The “advancing-response” neurons reacted to domoic acid with a similar prompt increase, whereas the “fluctuating-response” neurons displayed an even more delayed and fluctuating reaction (80 s delay). Therefore, we identify a subgroup of hippocampal neurons—in both slices and cultures—that respond to depolarization and domoic acid with an early [Ca²⁺]_i signal. Consistent with our data from cultures, we conclude these early-responding neurons are GABAergic. Their early GABA release directly explains the delayed Ca²⁺ response observed in glutamatergic neurons. We propose that this proactive mechanism, mediated by CP-KARs on GABAergic neurons, is a primary means of protecting the network from hyperexcitation. Furthermore, the activity of these CP-KAR-expressing neurons is itself regulated by GABAergic neurons containing CP-AMPARs. Full article

Microplastics (MPs) and antibiotics have emerged as contaminants of global concern, posing potential threats to ecosystem security and organismal health. To investigate the individual and combined toxicity of microplastics (PS-MPs) and sulfamethoxazole (SMX), we conducted a 120 h acute exposure experiment using embryo–larval zebrafish as a toxicological model. Our findings demonstrate that both PS-MPs and SMX can induce neurodevelopmental toxicity in embryo–larval zebrafish during embryonic development. Notably, PS-MPs and SMX exerted a significant synergistic effect. PS-MPs 1 µm in diameter were restricted to the chorion surface of pre-hatching zebrafish, whereas post-hatching, PS-MPs accumulated mainly in the gut and gills, with accumulation levels increasing progressively with exposure duration. Individual exposure to PS-MPs or SMX reduced spontaneous locomotion, decreased heart rate, and shortened body length in embryo–larval zebrafish. In addition to exacerbating these effects, coexposure further increased the incidence of malformations such as pericardial effusion and spinal curvature. PS-MPs and SMX significantly decreased the levels of dopamine (DA), serotonin (5-HT), and γ-aminobutyric acid (GABA) in zebrafish while also suppressing acetylcholinesterase (AChE) activity and increasing acetylcholine (ACh) levels. Moreover, upon coexposure at high concentrations, PS-MPs and SMX acted synergistically to reduce the levels of DA and GABA. The downregulation of key neurodevelopmental genes (elavl3, gap43, and syn2a) and related neurotransmitter pathway genes indicates that PS-MPs and SMX impaired structural development and functional regulation of the nervous system. An integrated biomarker response (IBR) index confirmed that PS-MPs and SMX significantly enhanced developmental neurotoxicity during early neurodevelopment in embryo–larval zebrafish through synergistic effects. Our study provides critical toxicological evidence for the scientific assessment of the ecological risks posed by microplastic–antibiotic cocontamination. Full article

Bentonite is a multifunctional material widely used in industry, agriculture, food processing, and medicine due to its strong binding and absorption properties. This study investigates the effects of bentonite pre-treatment at different concentrations (0.5–5%) on soybean sprout growth and nutritional quality. Moderate levels, particularly 1–3% (BP-1 and BP-3), significantly increased sprout yield (up to 16.1%) and vitamin C content (up to 18.91 mg/100 g FW), while maintaining desirable moisture and visual quality. Color evaluation showed higher yellowness (b*), suggesting improved consumer appeal. Mineral profiling indicated substantial enhancement of essential minerals across treatments, with the highest total mineral content recorded in the BP-5 group. Phosphorus, potassium, copper, and iron were notably enriched; however, elevated copper and reduced zinc at higher concentrations indicate potential nutritional risk. Isoflavone analysis revealed increased total isoflavones, especially glucoside forms such as daidzin and genistin, while aglycones like genistein decreased, reflecting bentonite’s selective influence on isoflavone metabolism. Antioxidant properties—including DPPH scavenging capacity, total polyphenols, flavonoids, and SOD-like activity—were significantly enhanced. Amino acid profiling also showed increases in essential amino acids, including methionine and valine, along with higher γ-aminobutyric acid (GABA). Overall, bentonite demonstrates strong potential as a natural additive for improving soybean sprout productivity and functional quality, with the most favorable outcomes observed at 1–3% concentrations. Full article

Lactiplantibacillus plantarum is widely used in fermented foods and as a probiotic, yet the genomic basis underlying its γ-aminobutyric acid (GABA) production capacity and strain-level functional diversity remains incompletely resolved. We analyzed 1240 publicly available genomes to map species-wide genome architecture, the distribution of GABA-related genes, and accessory drivers of phenotypes. Pangenome analysis identified 45,201 gene families, including 622 strict core genes (1.38%) and 444 soft-core genes (2.36%). The accessory genome dominated (3138 shell and 40,997 cloud genes; 97.64%), indicating a strongly open pangenome. In contrast, the GABA (gad) operon was universally conserved: gadB (glutamate decarboxylase) and gadC (glutamate/GABA antiporter) were present in all genomes regardless of isolates source. Accessory-genome clustering revealed ecological and geographic structure without loss of the operon, suggesting that phenotypes variability relevant to fermentation and probiotic performance is primarily shaped by accessory modules. Accessory features included carbohydrate uptake and processing islands, bacteriocins and immunity systems, stress- and membrane-associated functions, and plasmid-encoded traits. Analysis of complete genomes confirmed substantial variation in plasmid load (median = 2; range = 0–17), highlighting the role of mobile elements in niche-specific adaptation. Carbohydrate-Active Enzymes database (CAZy) and biosynthetic gene cluster (BGC) profiling revealed a conserved enzymatic and metabolic backbone complemented by rare lineage-specific functions. Collectively, these results position L. plantarum as a genetically stable GABA producer with extensive accessory-encoded flexibility and provide a framework for rational strain selection. Full article

Inoculated fermentation can enhance the flavor, nutrition, and functionality of juice. The lactic acid bacteria (LAB) are commonly used as starter cultures. This study screened LAB for orange juice fermentation and optimized fermentation factors using response surface methodology (RSM) to improve GABA content in orange juice. A total of 52 LAB strains were screened, and Lacticaseibacillus paracasei ZY (Lcb. paracasei ZY) and Lacticaseibacillus rhamnosus SN12 (Lcb. rhamnosus SN12) presented higher GABA yields and adaptability to substrates. The optimized fermentation factors for GABA enhancement in orange juice were as follows: initial pH of 5.5, fermentation temperature of 37 °C, soluble solids content of 12.0 °Bx, inoculum ratio of Lcb. paracasei ZY to Lcb. rhamnosus SN12 as 1:1, inoculum size of 6 Log CFU/mL, and fermentation time of 96 h. Under these optimized conditions, the GABA content reached 0.89 g/L, representing a 39.06% increase compared to uninoculated orange juice. This indicates that RSM-based optimization is conducive to increasing GABA content in orange juice and provides a scientific basis for the development of GABA-enriched functional fermented juices. Full article

Fermented vegetables host complex microbiomes that drive flavor and functionality. We compared cowpea pod fermentations produced by a Korean kimchi-style method (HG) versus a Sichuan paocai-style method (SC) to isolate technique-driven effects on community structure and functional potential. Cowpea pods were fermented for 10 days in triplicate, profiled by 16S rRNA (V3-V4) amplicon sequencing, analyzed in QIIME2, and functionally inferred with PICRUSt2. SC exhibited higher alpha diversity (Shannon, Chao1, Simpson) than HG (p < 0.05), and beta-diversity (Bray-Curtis dissimilarity) showed clear separation by fermentation style (PERMANOVA p = 0.001), indicating method-dependent community assembly. Both styles were dominated by lactic acid bacteria, chiefly Leuconostoc, Lactobacillus, and Weissella, but their proportions differed: HG retained higher Leuconostoc/Weissella, whereas SC favored Lactobacillus. Predicted functions diverged accordingly: HG was enriched for carbohydrate-metabolism genes (e.g., β-galactosidase; dextransucrase), consistent with rapid sugar fermentation and possible exopolysaccharide formation; SC showed enrichment of amino-acid-related pathways (e.g., acetolactate synthase; glutamate dehydrogenase), heterolactic fermentation, and γ-aminobutyric acid (GABA) biosynthesis, suggesting broader metabolic outputs relevant to flavor development and potential health attributes. Overall, fermentation technique substantially shapes both the microbiome and its predicted repertoire, with HG prioritizing carbohydrate catabolism and SC showing expanded metabolic potential; these insights can inform starter selection and process control for targeted product qualities. Full article

Enterococcus spp. produce diverse bioactive molecules used for biotechnological purposes or as probiotic agents for livestock and human health. The main aim of this study was to decipher the genetic traits using whole-genome sequencing (WGS) of a bacteriocinogenic Enterococus faecium 1702 strain showing diverse probiotic traits. Genetic traits of the strain were determined by performing WGS using the NovaSeq6000 platform followed by consecutive sequence analysis using appropriate software. WGS showed that the genome of the E. faecium 1702 strain has a size of 2,621,416 bp, with a GC content of 38.03%. The strain belonged to the sequence type ST722 not known as a human clonal lineage. The strain was free of genes encoding clinically relevant antibiotic resistance; in addition, genes encoding sensu stricto virulence factors, plasmids, and prophages were not detected. Annotations through the Prokaryotic Genomes Automatic Annotation Pipeline (PGAP) tool revealed 2413 coding sequencing entries (CDC) out of 2521 predicted chromosomal genes. The functional annotation of the whole genome through the KEGG database using KofaScan revealed several genes related to several biological activities, including metabolic process, carbohydrate metabolism, amino acid metabolism, and nucleotide metabolism. The strain harbored three entero-bacteriocins (enterocins) encoded by entA, entB, and entX (enterocin X-alpha and X-beta) genes. Interestingly, the strain harbored the ansB, glsA, and arcA genes encoding L-asparaginase, L-glutaminase, and arginine deiminase, respectively, known for their anticancer activities. E. faecium 1702 harbored the gadB, gadC, and gadR genes implicated in gamma(γ)-aminobutyric acid (GABA) production, which is known for its analgesic, anti-anxiety, hypotensive, diuretic, and antidiabetic effects. The WGS findings and phenotypic traits of E. faecium 1702 revealed significant features that allow for its use as a probiotic or for biotechnological and pharmaceutical applications. Full article

γ-Aminobutyric acid (GABA) is a bioactive metabolite valued in functional foods, but its microbial production is strongly influenced by nutrient availability. Levilactobacillus brevis CRL 2013 is an efficient GABA producer; however, its biosynthesis depends on culture medium composition. In this study, integrated physiological, proteomic, and transcriptional analyses were applied to assess the influence of nitrogen source composition and concentration on GABA production. No extracellular GABA was detected in a chemically defined medium containing all amino acids and glutamate (CDMg), whereas supplementation with yeast extract or Casitone restored high-level production. The highest GABA accumulation (~250 mM) was obtained in CDMg supplemented with 1% yeast extract or 2% Casitone, and a clear peptide dose-dependent effect was observed. In contrast, other protein hydrolysates or free amino acids alone did not stimulate GABA synthesis. Proteomic analysis revealed overexpression of the key enzyme GadB and changes in nucleotide and fatty acid pathways. Transcriptional analysis confirmed that peptide supplementation was accompanied by increased transcription of the gadRCB–gltX operon, in agreement with GABA accumulation. Overall, these results demonstrated that peptide composition and availability are critical determinants of GABA biosynthesis in Lv. brevis CRL 2013and provide a basis for optimizing peptide-based media to enhance GABA formation in food fermentations. Full article

Hair growth is orchestrated by a complex cycle comprising the anagen, catagen, telogen, and exogen phases that are largely regulated by dermal papilla cells (DPCs). The disruption of oxidative balance and inflammation impairs follicle function and regeneration. Fermented yeast complex extract (FYCE) is a bioactive material derived from enzymatically hydrolyzed yeast and collagen substrates through a two-step fermentation with Lactobacillus brevis and Lactobacillus plantarum, enriched in antioxidant amino acids such as γ-aminobutyric acid (GABA) and L-alanine. In this study, we evaluated the effect of FYCE on hair regrowth, with a focus on its modulation of oxidative stress and inflammatory pathways in hydrogen peroxide (H₂O₂)-treated DPCs. FYCE treatment significantly enhanced NRF2 expression (3.2-fold compared to H₂O₂-treated DPCs), a central transcription factor controlling antioxidant defense, and concomitantly suppressed NF-κB activity (0.6-fold compared to H₂O₂-treated DPCs), a key mediator of inflammation. Importantly, FYCE also attenuated the activation of the NLRP3 inflammasome, as evidenced by the decreased expression levels of its molecular components. Complementary studies showed that FYCE increased IGF-1 (5.4-fold compared to H₂O₂-treated DPCs), Wnt10b (1.8-fold compared to H₂O₂-treated DPCs), and Wnt3a (2.9-fold compared to H₂O₂-treated DPCs), and stabilized β-catenin (2.8-fold compared to H₂O₂-treated DPCs). FYCE also showed these changes in the shaved animal skin, which was associated with increased hair follicle number (1.6-fold compared to the water-administered control group) and the anagen phase (3.0-fold compared to the water-administered control group). Collectively, our results suggest that FYCE promotes hair regrowth through the dual modulation of antioxidative and anti-inflammatory pathways, specifically by activating NRF2, inhibiting NF-κB signaling, and downregulating the NLRP3 inflammasome. These findings support FYCE as a promising candidate for further investigation as a treatment to prevent or reverse hair loss, with in vivo and clinical studies substantiating its efficacy and safety. Full article

Depression is a common mood disorder, and growing evidence has revealed the critical role of gut microbiota in its onset and progression. The gut–brain axis, which connects the central nervous system and intestinal microecology, offers new strategies for depression intervention. In this study, an acute depression model was established in mice using lipopolysaccharide (LPS), and the potential antidepressant effects and mechanisms of Bifidobacterium animalis CP-9 were investigated. The results indicated that CP-9 may exert antidepressant effects through multiple pathways, including modulation of peripheral and central inflammatory responses, restoration of gut microbiota balance, enhancement of short-chain fatty acid (SCFA) production, and regulation of neurotransmitter metabolism such as γ-aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT). Notably, intervention with CP-9 at a dose of 10⁸ CFU/mL significantly alleviated depressive-like behaviors in mice, suggesting its promising potential in the prevention and treatment of mood disorders. Full article

Background: The accumulation of β-amyloid plaques, neurofibrillary tangles, and neuroinflammation are key hallmarks of Alzheimer’s disease (AD). Reactive oxygen species (ROS) act as major triggers and amplifiers of neuroinflammatory responses, contributing to immune dysregulation and neuronal damage. Despite extensive research, no effective therapy halts or reverses AD progression, emphasizing the need for alternative preventive strategies, including the use of natural compounds. Objectives: This study evaluated the neuroprotective effects of simulated digestive fractions (permeate fraction) of mushroom biomass (MB)—Trametes versicolor (TV), Hericium erinaceus (HE), and Pleurotus ostreatus (PO)—and key gut microbiota-derived metabolites, such as short-chain fatty acids (SCFAs) and γ-aminobutyric acid (GABA) on ROS production in human microglial cells (HMC3) and in transgenic Caenorhabditis elegans models exhibiting hyperphosphorylated Tau and β-amyloid-induced toxicity. Methods: Cell viability and ROS production were assessed in HMC3 cells treated with mushroom fractions and metabolites. Chemotaxis and paralysis assays were performed in transgenic C. elegans strains expressing hyperphosphorylated Tau or β-amyloid proteins. Results: Mushroom digestive fractions and SCFAs significantly decreased ROS levels in HMC3 cells. Moreover, mushroom digestive fractions, butyric acid, and GABA improved behavioral outcomes in C. elegans, enhancing chemotaxis and delaying paralysis. These effects were dose-dependent and varied among mushroom species and metabolites. Conclusions: Mushroom-derived digestive fractions and microbiota-related metabolites exhibit neuroprotective activity by modulating oxidative stress and mitigating neurodegeneration-associated behaviors. Diets enriched with such MBs may support preventive strategies for neurodegenerative diseases. Further research is required to elucidate the molecular mechanisms underlying these protective effects and their translational potential for human neurodegenerative diseases. Full article

This study aimed to isolate and screen lactic acid bacteria (LAB) with neuroprotective potential for food applications. Fifteen strains were screened for probiotic potential properties, γ-aminobutyric acid (GABA) production, and acetylcholinesterase (AChE) inhibitory activity. Lactobacillus delbrueckii AY8 and AY15 demonstrated the strongest probiotic potential, AChE inhibitory activity, and GABA production. Whole-genome sequencing confirmed genes linked to these probiotic and neuroprotective traits. To assess their functionality in a food matrix, the strains were used as adjunct cultures in fermented milk with and without jujube kernel powder (JP). Fermentation with the AY8 strain in JP-fortified milk significantly increased bioactive compounds, resulting in higher total phenolic content (235.75 mg GAE/g), flavonoids (114.07 mg RE/g), and superior antioxidant activity (110.24 mg Ascorbic equivalent/100 g). This biotransformation led to a remarkable increase in AChE inhibition, with the AY8-fermented sample achieving 30.66% inhibition, significantly higher than the JP control (18.27%) and the plain control (12.30%). The combination also improved the product’s viscosity and sensory profile. This study highlights the successful discovery of novel L. delbrueckii strains, whose application in a food model, when combined with a plant-based supplement, creates a functional food with enhanced neuroprotective potential, underscoring the role of microbial metabolism in food functionality. Full article

γ-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the central nervous system. However, GABA receptors, notably at the neuromuscular junction (NMJ), have also been identified in the peripheral nervous system. Here, we studied GABA_B receptor (GABA_B–R)-mediated regulation of acetylcholine (ACh) release in mouse NMJs during early postnatal development. The results revealed that, depending on the age of the mice, the activation of GABA_B–R had the opposite effect on ACh release. At the NMJ in mice on the second postnatal (P2) day, the GABA_B–R blocker CGP 55845 (5 μM) significantly increased the level of ACh release, whereas the GABA_B–R agonist baclofen (10 μM) decreased ACh release. In P14-aged mice, CGP 55845 decreased ACh release, while the application of baclofen significantly increased the release. At the NMJ of P14 mice, the mechanism of the ACh release-potentiating effect of GABA_B–R activation involves N-type calcium ion channels and small-conductance calcium ion-activated potassium ion channels. Full article

Listeria monocytogenes (L. monocytogenes) is a major foodborne pathogen which can invade intestinal epithelial cells and cause severe systemic infection. Probiotics, as well as their surface layer proteins, hold broad promise for enhancing intestinal barrier function and defending against pathogenic invasion. In the present study, the antagonistic effects of surface layer protein ornithine carbamoyltransferase (OTC) from Enterococcus faecium (E. faecium) WEFA23 against L. monocytogenes were systematically evaluated in vitro in human intestinal epithelial Caco-2 cells, including assessments of anti-adhesion and anti-invasion capacity, inflammatory cytokine responses, intestinal barrier integrity, and transcriptomic changes, by comparing the effects of wild-type E. faecium WEFA23 and a previously constructed E. faecium WEFA23 otc gene knockout strain (E. faecium WEFA23 otc^−/−). The results demonstrated that E. faecium WEFA23 achieved significant stronger anti-adhesion and anti-invasion capacity of L. monocytogenes (p < 0.05) in the presence of OTC, potentially through increasing tight junction protein expression, regulating inflammatory cytokines, and modulating the virulence factors of the pathogen. To elucidate the potential mechanism of the inhibitory effect of OTC protein, RNA-seq was performed. The results revealed that the significantly regulated core differentially expressed genes (DEGs), including ADCY2, OARI3, CCL5, and CXCL9, were found to be involved in γ-aminobutyric acid (GABA)-ergic synapse, calcium, and toll-like receptor signaling pathways. These findings demonstrated that OTC is involved in blocking Listeria invasion and revealed the function of the OTC from E. faecium WEFA23 in antimicrobial and intestinal mucosal defense, providing a conceptual foundation for the development of new probiotic intervention strategies in anti-infection. Full article