Search Results (648)

Reproductive inefficiency associated with impaired oocyte competence and embryonic loss remains a major limitation in livestock production. Although glycine is classified as a non-essential amino acid, its endogenous synthesis is often insufficient to meet increased metabolic demands during gestation and early embryonic development. This suggests that glycine has a conditionally essential role in reproductive physiology. However, the mechanisms through which glycine integrates metabolic and signaling processes to regulate reproductive outcomes are not fully understood. This review summarizes the recent advances in understanding glycine’s role in animal reproduction, emphasizing its function as a metabolic regulator rather than merely a structural component. Glycine contributes to reproductive processes by maintaining redox homeostasis, supporting mitochondrial function and stabilizing cellular environments as part of its osmolyte function during critical developmental stages. Additionally, glycine participates in one-carbon metabolism, influencing nucleotide synthesis and epigenetic regulation. Furthermore, emerging evidence suggests that glycine may modulate key signaling pathways, including the AMP-activated protein kinase (AMPK)-mechanistic target of rapamycin complex 1 (mTORC1) pathway. Consistent with these mechanistic roles, glycine supplementation has been associated with improvements in oocyte maturation and embryonic development, particularly in vitro. These findings highlight the potential of glycine as a dietary or culture medium supplement to enhance reproductive performance in livestock. However, most current evidence is derived from in vitro systems, and the translation of these findings into livestock production strategies requires validation through well-designed in vivo studies. Full article

As a precious indigenous goose resource in China, the Zhedong white goose occupies an essential position in the domestic goose industry. However, this breed spontaneously enters a prolonged non-laying period of over two months per year, which greatly limits egg production capacity and restricts the economic development of the goose industry. Herein, this study systematically compared serum physiological indices and serum and fecal metabolome, as well as fecal microbial communities, between laying and non-laying Zhedong white geese, aiming to reveal the key regulatory mechanisms underlying reproductive stage transition. Physiological analyses indicated that non-laying geese had higher serum levels of GnRH, PRL, APOA, and T-AOC, whereas the concentrations of LH, E₂, TNF-α, IL-1, and calcium were significantly reduced; FSH, PROG, and BA levels showed no significant differences between the two groups. Metabolomic analysis identified 277 upregulated and 403 downregulated DAMs in feces, and 386 DAMs in serum. The shared enriched pathways across serum and fecal samples encompassed arginine biosynthesis, histidine metabolism, and pantothenate and CoA biosynthesis, as well as steroid hormone biosynthesis. A total of 120 DAMs overlapped in two specimens, and the non-laying geese presented pronounced depletion of tryptophan-derived metabolites and steroid hormone-related metabolites. Metagenomic results showed no significant difference in gut microbial alpha diversity between groups, while their microbial community structures were clearly differentiated. A total of 774 upregulated and 854 downregulated microbial species were screened in non-laying geese, and these differential microbes were primarily enriched in pathways associated with reproductive hormone signaling, steroid biosynthesis and energy metabolism. Multi-omics correlation analysis verified close associations between differential microbes and reproductive-related metabolites. Certain probiotic strains, including Pediococcus pentosaceus and Lactococcus raffinolactis, were positively correlated with steroid hormones and tryptophan metabolites, and their abundances declined obviously in the non-laying stage. Collectively, this study elaborates the holistic changes in serum biochemistry, gut metabolome and microbiome in geese at different reproductive stages. The dysregulation of amino acid and steroid hormone metabolism, combined with the loss of beneficial intestinal microbes, jointly induces the non-laying phenotype. This study provides new perspectives for understanding the gut–reproductive axis and supplies promising biomarkers to improve the laying performance of geese. Full article

This work reports the colloidal synthesis of Nd-containing mixed-halide perovskite quantum dots described as CsPb(Nd)Br_3−γCl_γ, followed by post-synthetic surface modification with an acid-activated amino-functional siloxane. This notation is used deliberately because the available FE-SEM, DLS, EDX, and optical data confirm the formation of an Nd-containing mixed-halide colloidal perovskite system, but do not provide direct crystallographic proof of substitutional Nd³⁺ incorporation at the Pb²⁺ B-site. The obtained dispersions show stable blue emission with a maximum at about 458 nm, a photoluminescence quantum yield of about 56%, an essentially invariant emission maximum when the excitation wavelength is varied from 300 to 390 nm, and monoexponential decay kinetics with a characteristic lifetime of 6.67 ± 0.97 ns. Field-emission scanning electron microscopy combined with morphometric analysis of at least 150 particles indicates a nanoscale size distribution with an average equivalent diameter of 8.8 nm, a median of 7.3 nm, and 93.25% of particles smaller than 25 nm. Dynamic light scattering confirms a narrow hydrodynamic size distribution in the 7–9 nm range and a low polydispersity index. Elemental mapping by EDX confirms the co-presence of Cs, Pb, Br, Cl, and Nd in the analyzed particles. The observed blue shift is discussed in terms of the combined effect of chloride incorporation, nanoscale size, possible Nd-related perturbation of the local electronic/defect structure, and reduced non-radiative losses after surface passivation. No definitive crystallographic assignment of Nd to a specific lattice site is claimed; the composition is therefore treated as nominal, and the structural interpretation remains provisional pending XRD/XPS or related studies. Full article

Background: The residues of Camphora officinarum c.t. borneol after essential oil extraction are often discarded, causing resource waste and environmental pollution, while the edible fungi industry is facing a shortage of traditional cultivation substrates. Methods: This study integrated UPLC-MS/MS and GC-MS to comprehensively profile volatile and non-volatile metabolites. Samples included fresh branches and leaves (ZSXY) and residues after steam distillation (ZSZL), boiling combined with distillation (ZSSZ), and sun-drying after distillation (ZSSG). Results: In total, 2454 metabolites across 25 categories were detected. PCA revealed clear separation between fresh samples and all processed samples, with ZSZL and ZSSZ exhibiting similar metabolic profiles that were distinctly separated from ZSSG. Compared with ZSXY, most metabolites decreased after processing. ZSSG exhibited the strongest degradation, with 1408 down-regulated and only 146 up-regulated metabolites, and total terpenoid content decreased by 92.27%. ZSZL retained the highest levels of nutrients (e.g., amino acids and nucleotides) and bioactive compounds (e.g., phenolic acids, flavonoids, terpenoids), with 322 up-regulated metabolites. Among the specific comparisons, 113, 212, and 487 differentially accumulated metabolites were identified in ZSXY vs. ZSZL, ZSXY vs. ZSSZ, and ZSXY vs. ZSSG, respectively. KEGG enrichment revealed distinct pathway alterations: monoterpenoid degradation and biosynthesis pathways were activated in ZSZL, nitrogen metabolism-related pathways were disturbed in ZSSZ, and both limonene and pinene degradation and aminoacyl-tRNA biosynthesis pathways were enriched in ZSSG. Conclusions: Based on metabolomic profiling, steam distillation residues exhibited favorable retention of nutrients and bioactive compounds, whereas sun-drying led to excessive metabolite loss. These findings support the valorization of processing residues and promote circular agriculture. However, whether these residues can serve as effective substrates for edible fungi cultivation remains to be tested in dedicated cultivation trials. Full article

Sexual maturity in tiger pufferfish (Takifugu rubripes) consumes substantial metabolic energy, constraining somatic growth and limiting meat yield. Artificial triploid induction (sterility) may redirect energy toward somatic growth. Cold-shock induced triploids were compared with diploid controls using muscle and liver tissues, and the phenotype, histology, nutritional composition, hormone levels, as well as transcriptome profiles were assessed. After 5 months, triploids attained significantly greater body length and body weight, with larger muscle fiber diameter but lower fiber density. The triploids yielded lower ash content and higher amounts of total (TAA), essential (EAA), non-essential (NEAA), and delicious amino acids (DAA), as well as higher total fatty acids (TFA), total polyunsaturated fatty acids (PUFA), and omega 3 polyunsaturated fatty acids (n-3 PUFA). Growth-related hormones were elevated, including growth hormone (GH), testosterone (T), triiodothyronine (T₃), and thyroxine (T₄). Muscle transcriptome sequencing identified 231 differentially expressed genes, predominantly enriched in pathways related to cell growth regulation, metabolic processes, and energy conversion. These results provide reference data for breeding programs. Full article

This study aims to conduct a comparative analysis of the quality and flavor of meat from four categories of Mongolian horses (Wushen, Baicha, Barhu, and Ujimqin). Physicochemical indicators, electronic nose, electronic tongue, and lipidomics were used to characterize meat quality and flavor and to screen for differential markers. Results showed that Wushen Horses had the highest pH_45min, serine, glutamic acid, total free amino acids (∑FAA), total non-essential amino acids (∑NEAA), total amino acids (∑TAA), NEAA/TAA, W2S sensor response, umami and richness values, and had the lowest cooking loss, EAA/TAA, EAA/NEAA, sourness, bitterness and aftertaste B values (p < 0.01). In contrast, Barhu Horses had the highest b*_45min, C20:2 and saltiness values, and had the lowest W5S, W1S and W2W sensor responses (p < 0.01). Lipidomics identified 163 differential lipids (DELs) as potential markers, including LPC (18:2/0:0) and PC (16:0_16:0). Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed DELs were significantly enriched in glycerolipid, linoleic acid, arachidonic acid and α-linolenic acid metabolism pathways. Correlation analysis indicated 23 DELs (e.g., carnitine C20:4) correlated positively with umami, W2S and richness, but negatively with shear force and cooking loss. In summary, our data show that among the four categories of Mongolian horses, Wushen Horses exhibited the best meat quality and flavor, while Barhu Horses showed the poorest. The differences in meat quality and flavor were closely associated with changes in lipid composition. This study provides direct molecular evidence from lipids for the variation in meat quality among Mongolian horses. Full article

Different host plants influence the nutritional and metabolic profiles of the fall webworm (Hyphantria cunea), a globally invasive pest. This study investigated the proximate composition, free amino acid and lipid profiles of its pupae from larvae reared on three distinct diets (Robinia pseudoacacia, Morus alba and Armeniaca sibirica). The results showed that pupal weight and size varied significantly with host plant. The pupae contained 64.94 ± 1.57% crude protein and 30.82 ± 0.53% crude fat (dry mass basis), with high levels of magnesium and calcium. A total of 82 free amino acids and their metabolites were identified, including all essential and non-essential amino acids. In addition, 1026 lipids were detected, with triacylglycerols as the predominant class. Notably, the levels of linoleic and α-linolenic acid were highest in the pupae fed on R. pseudoacacia. Among the three diet groups, the lipid species TG (16:0_16:2_20:5) was identified as a characteristic differential metabolite. These findings show that host-plant-induced nutritional variation reflects metabolic plasticity, which underlies the dietary adaptability and invasion success of this polyphagous pest and also suggestsits potential use as a feed ingredient. Full article

Plant quality is strongly influenced by environmental conditions, including the presence of micronutrients and potentially toxic elements in the soil. This study aimed to evaluate the effect of soil-applied fluorine on the content of exogenous (essential) and endogenous (non-essential) amino acids in black radish roots and the aerial biomass of narrow-leaved lupine. The following essential amino acids were identified: histidine, threonine, arginine, lysine, tyrosine, leucine, phenylalanine, isoleucine, methionine, and valine. The group of endogenous amino acids comprised cysteine, proline, serine, glutamic acid, aspartic acid, glycine, and alanine. Increasing fluorine application generally enhanced the accumulation of both essential and endogenous amino acids in lupine shoots and radish roots. The strongest stimulatory effect on the synthesis of most amino acids was observed at the lowest fluorine doses, i.e., 20 mg F kg⁻¹ soil for narrow-leaved lupine and 100 mg F kg⁻¹ soil for black radish. By contrast, the concentrations of certain endogenous amino acids, such as aspartic acid, glutamic acid and proline in radish roots and aspartic acid in lupine shoots, were highest at intermediate fluorine contamination levels. Moreover, the maximum contents of tyrosine and cysteine in lupine aerial parts were recorded under the highest fluorine dose. Overall, protein derived from black radish exhibited a higher nutritional value than that of narrow-leaved lupine. The results obtained show that simulated soil contamination with fluoride stimulates amino acid synthesis in both plants. The research enables a better assessment of the quality and nutritional value of crops grown under conditions of environmental contamination, and helps to explain the mechanisms by which plants defend themselves against chemical stress. The research suggests that moderate fluoride contamination causes changes in nitrogen metabolism, increasing amino acid production, which may be a defence mechanism in plants against stress. Full article

To evaluate the nutritional enrichment effects of Euphausia superba meal on Moina mongolica Daday, different concentrations of krill meal (26, 39, 52, and 65 mg·L⁻¹) were applied as enrichment supplements, with non-enriched M. mongolica serving as the control. After a 6 h enrichment period, the compositions and contents of amino acids and fatty acids in M. mongolica were analyzed, and the astaxanthin content was simultaneously determined. The results showed that, compared with the control group cultured on a mixed diet of photosynthetic bacteria, yeast, and Nannochloropsis, enrichment with Antarctic krill meal at appropriate concentrations (26–39 mg·L⁻¹) markedly altered the fatty acid profile of M. mongolica. In particular, the levels of highly unsaturated fatty acids (HUFAs), including ∑ω6-PUFA and ∑ω3-PUFA, were significantly enhanced, with a pronounced increase in eicosapentaenoic acid (EPA). Furthermore, the total amino acid content, as well as the contents of six flavor-enhancing amino acids and ten essential amino acids for fish, were significantly higher in the enriched groups than in the control (p < 0.05). However, excessive supplementation of krill meal inhibited the growth of M. mongolica, suggesting a concentration-dependent effect. In addition, enrichment with whole Antarctic krill meal for 6 h did not significantly increase the astaxanthin content in M. mongolica, which may be related to the limited assimilation efficiency within the short enrichment duration. Overall, enrichment of M. mongolica with Euphausia superba meal at appropriate concentrations (26–39 mg·L⁻¹) effectively improves its fatty acid and amino acid composition, thereby enhancing its nutritional value as live feed for aquaculture larvae. Full article

Background: Post-COVID-19 syndrome is associated with endothelial dysfunction (ED) and various sequelae, particularly in individuals who experienced critical illness during the acute phase, affecting lung function and the musculoskeletal system. L-citrulline, a nonessential amino acid, has been shown to improve endothelial function, systemic inflammation, blood pressure, and physical performance. This study aimed to assess the effects of L-citrulline supplementation on ED and body composition in patients with post-COVID-19 syndrome. Methods: We conducted an open-label randomized controlled clinical trial at the Instituto Nacional de Enfermedades Respiratorias in Mexico City, Mexico, from February 2021 to May 2022. Eligible subjects were adults aged ≥18 years who recovered from COVID-19 and required hospitalization during acute COVID-19. Participants were randomized 1:1 into two groups: (1) the L-citrulline group (4 g/day) and (2) the control group. The intervention lasted three months. Endothelial-related biomarkers, including endothelin-1, sE-selectin, ICAM-1, and VCAM-1, were investigated. Body composition was measured using electrical bioimpedance, and aerobic capacity was assessed with the 6 min walk test (6MWT). Treatment effects were analyzed using two-way repeated-measures ANOVA (group × time). Results: In total, 43 subjects participated in the study. After three months of follow-up, the intervention group showed a decrease in ICAM-1 (−32.59 ng/mg of protein; 95% CI −52.85 to −12.33 vs. −2.31 ng/mg of protein, CI 95%: −21.59 to 16.95, p = 0.034) and an increase in 6MWT (141.2 m; 95% CI: 98.40 to 184 vs. 67.70 m, CI 95%: 30.62 to 104.78, p = 0.011) compared with the control group. No differences in body composition were observed between the groups at follow-up. Conclusions: L-citrulline supplementation for three months decreased ICAM-1 and increased 6MWT. Full article

The clinical management of nutrition in acute and chronic diseases requires an integrated understanding of the interactions between energy intake, dietary protein, and amino acids (AAs). Many conditions (including sepsis, major trauma, cancer cachexia, chronic heart failure, chronic obstructive pulmonary disease, renal and liver failure, autoimmune diseases, and aging) share a common pathophysiological feature: the hypercatabolic state (HCS). HCS is characterized by systemic inflammation and neuroendocrine activation that increase basal metabolic rate, induce insulin resistance, and accelerate skeletal muscle proteolysis, leading to negative nitrogen balance, sarcopenia, and cachexia. Under these conditions, skeletal muscle acts as a metabolic reservoir of AAs mobilized to support energy production, gluconeogenesis, immune function, and vital organ metabolism, often at the expense of lean body mass and clinical outcomes. This narrative review examines the distinct and non-overlapping roles of calories, proteins, and AAs in metabolic regulation, with a particular focus on HCS. Calories primarily act as a permissive factor for protein utilization, whereas proteins and especially essential amino acids (EAAs) function not only as substrates for protein synthesis but also as signaling molecules (metabokines) regulating anabolic and catabolic pathways, including mTORC1 and AMPK. Energy provision alone is insufficient to prevent muscle loss when EAA availability is inadequate, while high protein intake without sufficient energy fails to sustain anabolism due to anabolic resistance. Evidence indicates that protein quality and the balanced availability of all EAAs are more critical for lean mass preservation than total caloric intake alone. Strategies based solely on calorie provision or protein quantity are therefore limited, whereas targeted EAA supplementation may partially overcome anabolic resistance in selected hypercatabolic conditions. Overall, this review supports a shift from calorie-centered nutrition toward a signal-based, quality-oriented approach, based on personalized needs, that integrates metabolic status, protein quality, and AA signaling to preserve lean body mass and improve clinical outcomes. Full article

Over the past decade, changes in consumer dietary habits have driven an increasing demand for protein-enriched confectionery products. Consequently, research has increasingly focused on the utilization of alternative protein origins, including Acheta domesticus. This research paper aims to characterize Acheta domesticus protein powder (CP) in terms of its functional properties and chemical composition. In addition, the amino acid profile was determined using HPLC, while antioxidant capacity was evaluated by spectrophotometric methods (including the ABTS assay). Edibility was further assessed in proteins, both in their native form and after incorporation into cocoa cream products, using an in vitro digestion model. The results indicated that methionine was the most abundant essential amino acid in CP (17.71 mg/100 g protein), while glycine was the predominant non-essential amino acid (42.38 mg/100 g protein). CP also demonstrated high solubility (80.00%) and notable water- and oil-binding capacities (90.26% and 94.87%, respectively). However, its emulsifying properties were limited, as emulsifying stability was maintained for only 26 min. In contrast, digestibility results indicated strong protein hydrolysis in both native and cocoa cream samples enriched with CP in different concentrations (10, 12.5 and 15%), hereafter designated as CPC10, CPC12.5, and CPC15. The degree of hydrolysis was higher after the digestion process, with 39.11% for the control and 47.14%, 48.62% and 50.05% for the fortified samples—CPC10, CPC12.5 and CPC15, respectively. The ABTS assay further confirmed the increase in antioxidant activity after digestion. The ABTS values of the digested fortified samples ranged from 20.91% for CPC10 to 40.45% for CPC15, suggesting the release of bioactive peptides during gastrointestinal digestion. Overall, the findings highlight CP as a promising protein source for the fortification of cocoa cream products, which are naturally low in protein content. Full article

Glutamine is the most abundant amino acid in human plasma and tissues and plays essential roles in cellular metabolism, biosynthesis, and redox homeostasis. Beyond these canonical functions, glutamine availability and utilization have emerged as key regulators of multiple cellular stress responses, including the integrated stress response, endoplasmic reticulum stress, metabolic checkpoint signaling, and autophagy. During viral infection, host glutamine metabolism is frequently reprogrammed to meet the energetic and biosynthetic demands of viral replication, thereby inducing or reshaping glutamine-linked stress pathways. Increasing evidence indicates that these stress responses are not merely secondary consequences of infection but actively influence key stages of the viral life cycle, including viral entry, genome replication, protein synthesis, and host antiviral responses. In this review, we summarize current advances in understanding how glutamine metabolism regulates cellular stress responses in the context of both viral and non-viral infections, and how these pathways, in turn, modulate viral pathogenesis and host defense. We discuss the context-dependent roles of glutamine-linked stress signaling in either promoting viral replication or restricting infection, depending on viral species, host cell type, and metabolic conditions. Finally, we highlight emerging concepts and unresolved questions, including the potential of targeting glutamine metabolism and associated stress pathways as host-directed antiviral strategies. A deeper understanding of the interplay between glutamine metabolism, cellular stress responses, and viral infection may provide new insights into disease mechanisms and inform the development of novel therapeutic approaches. Full article

The growing global protein demand and environmental concerns from conventional animal agriculture have driven the exploration of sustainable alternative protein sources. Single-cell proteins (SCPs) from microbial fermentation offer a promising solution. This study comprehensively evaluated the nutritional value and safety profile of SCP produced from Ralstonia eutropha H16 through integrated in vitro and in vivo assessments. Nutritional analyses revealed a high crude protein content of 71.87 ± 5.05 g/100 g dry weight, with total amino acids of 53.67 ± 1.05 g/100 g. The essential amino acid content was 24.38 ± 0.51 g/100 g, accounting for 45% of the total amino acids. An essential amino acid index (EAAI) of 1.46 ± 0.04 and an amino acid score (AAS) of 0.83 ± 0.06 confirmed its classification as a high-quality protein source according to FAO/WHO standards. In vivo rat feeding trials demonstrated an adjusted protein efficiency ratio (PER) of 1.81, exceeding common plant proteins such as wheat (0.8–1.1). True digestibility (TD) reached 85.73%, with a biological value (BV) of 49.37%, net protein utilization (NPU) of 42.33%, and protein digestibility-corrected amino acid score (PDCAAS) of 0.71. Comprehensive safety assessments included chemical contaminant screening, acute oral toxicity studies in rats and mice, in vitro chromosome aberration tests, and erythrocyte micronucleus tests. Heavy metals and aflatoxin B₁ levels were below regulatory limits. Acute oral toxicity studies established LD₅₀ values exceeding 10,000 mg/kg body weight in both rodent species, classifying this protein source as practically non-toxic. The 28-day sub-acute toxicity study showed no significant adverse effects at low doses (6.25% protein replacement). Both genotoxicity assays (mammalian cell chromosome aberration assay and mammalian erythrocyte micronucleus test) returned negative results. These findings establish R. eutropha H16-derived SCP as a safe, nutritious, and sustainable protein source with considerable potential for feed and food applications, contributing to global food security and environmental sustainability. Full article

Kale is widely recognized as a nutritional superfood. This study investigated the impact of carbon dioxide (CO₂) concentrations (400, 800, and 1200 µmol mol⁻¹) on the growth, yield, physiological responses, and nutritional contents of two kale cultivars (‘Curly Kale’ and ‘Red Ursa’) grown in a plant factory. A completely randomized design was used to evaluate these parameters. Based on the results, increasing the CO₂ concentration to 1200 µmol mol⁻¹ significantly enhanced stem height, shoot, and root fresh weight and dry weight in ‘Curly Kale’ and ‘Red Ursa’, compared to the other CO₂ concentrations. Increasing CO₂ concentration to 1200 µmol mol⁻¹ significantly enhanced net photosynthesis rate, stomatal conductance, transpiration rate, and water use efficiency in ‘Curly Kale’. In addition, compared to ambient CO₂, the increase in the CO₂ concentration to 800 µmol mol⁻¹ significantly increased the vitamin C, soluble protein, and total phenolic contents, while reducing the nitrate accumulation in both cultivars. However, further elevation to 1200 µmol mol⁻¹ CO₂ markedly decreased the vitamin C content and total amino acids, including both the essential and non-essential amino acids. Among the tested concentration gradients, 800 µmol mol⁻¹ CO₂ was identified as the most cost-effective level for maintaining nutrient density, whereas 1200 µmol mol⁻¹ CO₂ increased unit production costs for ‘Red Ursa’ due to a lack of significant yield returns. In conclusion, enriching the CO₂ concentration to 800 µmol mol⁻¹ provided a balance between improved growth, photosynthetic performance, and optimal nutritional quality, while ensuring economic feasibility and preserving the superfood identity of kale. Full article