Search Results (26,589)

This study aimed to characterize metabolomic changes in the eye lens of senescence-accelerated OXYS rats in comparison with control Wistar rats, and to identify biochemical shifts associated with genotype, age, and cataract progression. Cataract severity was clinically graded. Rats’ lenses were analyzed using quantitative ¹H NMR spectroscopy at 3.6 and approximately 4.5 months of age. A total of 43 metabolites were quantified. We found that at 3.6 months of age, OXYS lenses exhibited a significant accumulation of 17 metabolites, primarily amino acids, compared to Wistar rats, suggesting an imbalance between amino acid uptake and crystallin biosynthesis. However, by 4.5 months, OXYS lenses exhibited rapid metabolic changes characterized by significant decreases in amino acid, glucose, and key energy/antioxidant markers, including NAD, adenylate energy charge, and hypotaurine. Clinical cataract grade (Grade 2 vs. 3) had a negligible impact on the overall metabolomic profile. Our results indicate that profound metabolic reorganization, including an initial amino acid excess followed by energy and antioxidant depletion, precedes the morphological manifestation of cataracts in OXYS rats. We suggest that a biochemical “point of no return” occurs early in cataractogenesis, while subsequent increase in lens opacification is a secondary consequence of preexisting metabolic disturbances. Full article

Background: This study investigated the relationships among mitochondrial energy metabolism, immune function, and gut microbiota in mice under a fatigued state, providing preliminary evidence for future nutrition-related mechanistic and intervention studies. Methods: Mice were adaptively fed for 4 days and then randomly divided into a normal control group (NC) and a fatigue model group (NM). Immune organ indices, serum IgG levels, thigh muscle ATP content, mitochondrial respiratory chain complex I–IV activities, and gut microbiota composition were assessed using enzyme-linked immunosorbent assay (ELISA), microplate assays, and 16S rRNA gene sequencing. Results: Compared with the NC, the NM showed a significantly reduced spleen index, serum IgG levels, mitochondrial respiratory chain complex I, III, and IV activities, along with reduced ATP content. Regarding gut microbiota, mice in the NM exhibited disordered intestinal villus arrangement, inflammatory cell infiltration in the crypts and muscular layers, and markedly reduced intestinal microbial activity as well as protease and sucrase activities. 16S rRNA sequencing revealed fewer ASVs in the NM, with enrichment of Lactobacillaceae, Limosilactobacillus, and Ligilactobacillus, whereas the NC was characterized by Borkfalkiaceae and Borkfalkia. Linear discriminant analysis effect size (LEfSe) analysis identified Lactobacillaceae, Firmicutes_D, and Lactobacillales as characteristic taxa of the NM. Kyoto Encyclopedia of Genes and Genomes (KEGG) prediction indicated that fatigue-associated microbial functions were mainly related to carbohydrate, amino acid, and lipid metabolism. Correlation and RDA analyses further suggested that alterations in gut microbiota structure were closely associated with mitochondrial energy-related indicators and immune-related parameters. Conclusions: Fatigue was associated with alterations in energy metabolism, immune function, and gut microecology in mice. The “gut microbiota–energy metabolism–immunity” framework may represent a potential association-based framework and provides biological information to support future nutrition-related intervention studies. Full article

Background/Objectives: Obesity-associated metabolic dysfunction involves oxidative stress, gut barrier impairment, and gut–liver axis disruption. This study evaluated whether enzymatically prepared Solenocera crassicornis peptides (SCPs) provide additional benefits during diet normalization in HFD-induced obese mice and examined associations with antioxidant, microbial, and barrier markers. Methods: SCPs were characterized using UPLC-Q-TOF-MS/MS and amino acid analysis. Peptides underwent bioactivity prediction and Keap1 docking. After 7 weeks of HFD feeding, obese male C57BL/6J mice were switched to a normal diet and administered vehicle, orlistat, or SCPs for 4 weeks. Adipose tissue mass, serum lipid profiles, liver histology, hepatic antioxidant status, barrier-associated histological and biochemical markers, and gut microbiota composition were assessed. A simulated digestion–fecal fermentation model was used to assess the effects of fermentation products generated in the presence of digested SCPs on H₂O₂-induced oxidative injury and MUC2 secretion in LS174T goblet-like cells. Results: SCPs reduced epididymal and perirenal fat, improved serum lipids, improved hepatic steatosis-related morphology and enhanced hepatic antioxidant status. SCPs were also associated with improved intestinal morphology, increased mucin-associated staining, decreased serum diamine oxidase levels and reduced hepatic lipopolysaccharide accumulation. 16S rRNA sequencing showed SCP-associated microbial shifts, with correlations linking taxa to metabolic and barrier markers. Fermentation products generated in the presence of digested SCPs improved oxidative-stress and MUC2-related readouts in LS174T cells. Conclusions: During diet normalization, SCPs were associated with additional improvements in adiposity, lipid profiles, hepatic antioxidant status, intestinal barrier readouts, and gut microbiota. These findings support further investigation of SCPs as standardized marine protein hydrolysates, but active components, causal mechanisms, long-term efficacy, safety, and human relevance remain to be established. Full article

For over 70 years, microalgae have been considered promising ingredients for developing sustainable, nutritionally rich foods. Their high protein content, presence of essential amino acids, fatty acids, natural pigments, and a myriad of bioactive compounds position them as potential alternatives to conventional ingredient sources. However, despite their significant potential, the large-scale incorporation of microalgae into food products remains limited. This study presents a critical analysis of the main challenges associated with the use of microalgae in the food industry. Key bottlenecks include high production costs, technological difficulties related to biomass processing, and challenges in extracting desirable compounds. Additionally, the strong flavor, odor, and intense coloration of microalgal biomass can negatively affect sensory acceptance in food products. Other limitations involve scalability issues in cultivation systems, risks of contamination during production, and regulatory constraints related to food safety approval. Consumer perception and limited familiarity with microalgae-based foods also contribute to slower market adoption. Therefore, although microalgae represent a promising and sustainable food resource, overcoming technological, economic, and sensory barriers is essential for their broader integration into the food industry and for achieving successful market consolidation. Full article

Gelatin capsule waste (GCW), a protein-rich by-product, represents a promising substrate for the generation of potential bioactive substances, including free amino acids and other soluble substances generated during enzymatic hydrolysis. In this study, gelatin hydrolysates with degrees of hydrolysis (DH) ranging from 10% to 40% were produced using the commercial enzymes NS AC0106 (endopeptidase) and NS AC0107 (aminopeptidase) to enhance their functional properties. Increasing DH significantly improved antioxidant activity, surface hydrophobicity, and emulsifying capacity (p < 0.05), while sterilization further enhanced antioxidant capacity. Structural analyses confirmed extensive protein degradation and conformational modifications, as evidenced by SDS–PAGE (formation of low-molecular-weight substances), FTIR (shifts in the amide I region), and NMR (release of free amino acids). Electronic tongue analysis indicated that enzymatic hydrolysis enhanced umami and salty taste attributes. Notably, hydrolysis using NS AC0107 at 40% DH resulted in the highest antioxidant activity, together with pronounced umami taste and low bitterness. Overall, GCW-derived hydrolysates show considerable potential as functional ingredients and provide a sustainable strategy for the valorization of protein-rich industrial by-products. Full article

Edible insects are increasingly recognized as a viable alternative protein source, offering a potentially sustainable approach to addressing global food security challenges. This narrative review critically examines the nutritional composition, environmental advantages, techno-functional attributes, and potential applications of insect-based proteins within human food systems. Edible insects are characterized by high protein content, favourable essential amino acid profiles, and appreciable levels of key micronutrients, rendering them nutritionally comparable to conventional livestock-derived proteins. Moreover, insect production systems generally require substantially lower inputs of land, water, and feed, resulting in comparatively lower greenhouse gas emissions and reduced overall environmental burden. Despite these advantages, broader adoption remains constrained by challenges related to regulatory heterogeneity, food safety concerns, and limited consumer acceptance. Overall, the available evidence suggests that edible insects can function as a nutritionally adequate and environmentally sustainable complementary protein source; however, significant variability in nutrient composition, limitations in standardized safety assessment, and socio-cultural barriers currently restrict their large-scale integration into mainstream food systems. In addition, inconsistencies in analytical methodologies and reliance on in vitro data further complicate cross-study comparisons and translational relevance. Future research should focus on standardization of rearing and processing conditions, harmonization of evaluation frameworks (e.g., protein quality indices), comprehensive safety assessments, and well-designed clinical studies to validate nutritional and functional benefits, alongside the development of effective strategies to improve consumer acceptance and support regulatory alignment across regions. Full article

Generative artificial intelligence (AI) is transforming biological and medical research and data analysis. Beyond analyzing existing information, these models can learn complex patterns and generate new data such as realistic protein sequences, genetic variants, or clinical notes. In molecular biology, language-like sequence models can read and generate DNA, RNA, and amino acid sequences to predict genetic variant effects, design new proteins, and explore molecular functions. In medicine, large language models (LLMs) trained on biomedical literature and electronic health records (EHRs) can summarize clinical findings, identify patterns, and provide decision support for clinicians and healthcare providers. Additionally, synthetic data generation can help protect patient privacy and augment existing disease datasets. While these advances make tasks that were previously impractical possible at scale, they also carry major risks, including producing convincing but incorrect results, reflecting hidden biases in the training data, and underperforming when real-world conditions change. Full article

Background: L-tyrosine, classified as a dispensable amino acid, is widely consumed as a component of commonly consumed foods and as a dietary supplement. However, 4-week safety data on supplementation with this amino acid remain limited. Methods: The aim of this study was to evaluate the safety and tolerability of L-tyrosine supplementation over a 4-week period and to estimate the no-observed-adverse-effect level (NOAEL). In a randomized, double-blind, placebo-controlled crossover trial, 30 healthy adult men received L-tyrosine at graded daily doses (0, 1, 2, 3, or 4 g/day). Each participant received four of the five doses in a randomized sequence, with each intervention period separated by a 2-week washout period. The primary endpoints were clinical laboratory parameters, and the secondary endpoint was the incidence of adverse events. Anthropometric and dietary parameters were also assessed. In addition, plasma amino acid concentrations following L-tyrosine supplementation were evaluated as exploratory outcomes. Results: No clinically meaningful or statistically significant dose-related abnormalities were observed in hematological, biochemical, or electrolyte parameters at any dose. Anthropometric and dietary parameters remained unchanged. No serious adverse events occurred, and the incidence of mild-to-moderate adverse events was comparable to that observed with placebo. At the end of each supplementation period and under fasting conditions, plasma L-tyrosine concentrations modestly increased at the highest dose (4 g/day), whereas concentrations of other amino acids remained unchanged. Conclusions: Four-week supplementation with L-tyrosine at doses up to 4 g/day was well tolerated in healthy adult men and was not associated with biochemical and clinically relevant adverse effects under the conditions of this study. These findings suggest that 4 g/day represents the highest tested intake level without observable adverse effects and may serve as the NOAEL under the present 4-week study conditions. Full article

Mycoplasma pneumoniae pneumonia (MPP) is a leading cause of community-acquired pneumonia in children, yet little is known about the role of nasopharyngeal microbiota dysbiosis in susceptibility to infection and disease subtype. In this study, we performed 16S rRNA sequencing on nasopharyngeal samples from 102 pediatric MPP patients, 104 influenza A patients, and 103 healthy controls and compared the microbial diversity, composition, and functional profiles across groups. The MPP group exhibits an altered nasopharyngeal microbial composition, characterized by reduced microbial diversity and an increased relative abundance of genera including Mycoplasma, Pseudomonas, Acinetobacter, and Tannerella. Distinct microbiota profiles were identified for the MPP subtypes, with Mycoplasma more abundant in bronchopneumonia (BP) than in lobar pneumonia (LP). A microbial classifier based on the relative abundance of the nasopharyngeal microbiota was established to distinguish MPP patients from both influenza patients and healthy controls, with an area under the receiver operating characteristic curves of 0.978. Key microbial features associated with MPP included Mycoplasma, Mycobacterium, Aeromonas, and Acinetobacter. In addition, PICRUSt2-based functional predictions suggested alterations in amino acid metabolism and predicted functional pathways associated with bacterial infection and antimicrobial resistance in MPP patients. In conclusion, this study provides comprehensive insights into alterations in the nasopharyngeal microbiota in pediatric MPP. These findings highlight the potential role of dysbiosis in disease progression and suggest that changes in microbiota composition and functional profiles are associated with MPP infection. Full article

This experiment investigated the effects of two rearing systems, cage and free-range, on growth performance, serum biochemical parameters, slaughter performance, cecal microbiota, and hepatic metabolism of yellow-feathered broilers. A total of 240 healthy 21-day-old Liangfenghua yellow-feathered male broilers with similar body weight were randomly assigned to a cage group (LY) and a free-range group (SY), with 10 replicates per group and 12 birds per replicate. All birds were fed the same diet until 63 days of age. Compared with the LY group, the SY group had significantly lower final body weight, average daily gain, and abdominal fat percentage (p < 0.05), while average daily feed intake and feed-to-gain-ratio were significantly higher (p < 0.05). The Shannon and Simpson indices of the cecal microbiota were significantly higher in the SY group (p < 0.05), and the genera Bacteroides, Lactobacillus, Rikenella, and Oscillibacter were specifically enriched. A total of 560 differential metabolites were identified by liver non-targeted metabolomics, and these metabolites were significantly enriched in the necroptosis, cysteine and methionine metabolism, thiamine metabolism, and amino sugar and nucleotide sugar metabolism pathways (p < 0.05). Correlation analysis between cecal microbiota and liver metabolites revealed that the differentially abundant bacterial genera showed significant negative correlations with multiple amino acid metabolites in the liver. In conclusion, the free-range rearing system reduced the growth performance of yellow-feathered broilers but enriched specific bacterial genera, increased gut microbiota diversity, and modulated host amino acid metabolism and energy homeostasis through the “gut microbiota–liver” axis, ultimately inducing an adaptive metabolic state characterized by reduced abdominal fat deposition and remodeling of hepatic metabolic pathways. Full article

Honeybee brood is a nutrient-rich food source containing natural umami-active compounds, such as glutamic acid, aspartic acid, and 5′-nucleotides, which are responsible for its characteristic umami taste. This study aimed to optimize drying conditions to enhance the umami composition and sensory properties of honeybee brood umami powder (HBb-UP). A factorial design was employed to evaluate the effects of drying temperature and time on umami-related amino acids, 5′-nucleotides, and equivalent umami concentration (EUC). Drying temperature and time significantly influenced the formation of umami compounds, with the optimized drying condition (65 °C for 3 h) promoting higher umami composition and improved sensory attributes of HBb-UP. Volatile flavor analysis using GC–MS and an electronic nose revealed a diverse range of aroma compounds contributing to the overall flavor profile. Descriptive sensory evaluation and electronic tongue analysis indicated that umami and saltiness were the dominant taste attributes, accompanied by mild seasoning and fishy notes associated with interactions between amino acids and nucleotides. Principal component analysis demonstrated positive correlations among umami-related amino acids, nucleotides, EUC, and sensory attributes, confirming their combined contribution to taste perception. These findings highlight the potential of optimized HBb-UP as a natural flavor enhancer and functional ingredient for use in sustainable food systems. Full article

Microorganisms in sediments participate actively in biogeochemical cycling and are essential for maintaining the stability of marine ecosystems. To investigate the spatial impact of seaweed mariculture on sediment bacterial communities, three distinct zones were selected along the Zhanjiang coast, China: the Gracilaria salicornia aquaculture zone, a transition zone (adjacent to the aquaculture area), and a control zone (with no direct mariculture influence). In this study, 16S rRNA gene amplicon sequencing was employed to examine the composition, diversity, and potential functions of sediment bacterial communities across these three zones. The dominant microbial communities identified included Pseudomonadota, Thermodesulfobacteriota, Chloroflexota, and Acidobacteriota. Analyses of α-diversity, β-diversity, and molecular ecological network revealed that the bacterial community in the G. salicornia aquaculture zone exhibited significant differences in species composition, community structure, and interspecies interaction compared with those in the transition and control zones. Environmental factors such as pH, dissolved oxygen (DO) and nitrate (NO₃⁻) exerted significant influence on the bacterial community composition and structure. Predicted functional potential analyses indicated high abundances of pathways related to carbohydrate metabolism and amino acid metabolism. Overall, this study characterizes the spatial distribution patterns of microbial communities in a coastal seaweed mariculture ecosystem and provides important data to support further research on biogeochemical processes mediated by sediment bacteria and their response mechanisms to mariculture activities. Full article

1-Deoxy-D-xylulose-5-phosphate synthase (DXS) serves as the initial rate-limiting enzyme in the methylerythritol phosphate (MEP) pathway, governing the biosynthesis of precursors for photosynthetic pigments and terpenoids. In this study, the LaDXS2-2 gene was cloned and functionally characterized in lavender (Lavandula angustifolia). The full-length coding sequence (CDS) of LaDXS2-2 spans 2178 base pairs, encoding a protein of 725 amino acids. Phylogenetic analysis revealed that LaDXS2-2 is most closely related to the DXS from Salvia miltiorrhiza. Expression profiling demonstrated that LaDXS2-2 was highly expressed in flower buds, and its transcript levels were significantly upregulated (p < 0.05) in response to ethephon, high light intensity, and low temperature, while exhibiting tissue-specific responses to gibberellin application. Subcellular localization assays confirmed LaDXS2-2 is targeted to the chloroplast. Heterologous overexpression of LaDXS2-2 in tobacco resulted in a marked increase in photosynthetic pigment content, enhanced the actual photochemical efficiency of photosystem II [Y(II)], and reduced non-photochemical quenching (NPQ). Integrated transcriptomic and metabolomic analyses further revealed that LaDXS2-2 overexpression activated the diterpenoid biosynthesis pathway and upregulated amino acid metabolism as well as the TCA cycle, while competitively suppressing phenylpropanoid and flavonoid biosynthesis pathways. These findings indicate that LaDXS2-2 not only enhances photosynthetic efficiency by promoting the synthesis of photosynthetic pigments but also suggests a potential role in influencing primary carbon and nitrogen metabolism, as inferred from transcriptomic and metabolomic data. This functionality may ultimately influence plant growth and metabolic homeostasis. Overall, this study provides a theoretical foundation for the synergistic improvement of photosynthetic efficiency and secondary metabolism in crops. Full article

Background: Abnormalities in energy and amino acid metabolism are potentially involved in hepatocellular carcinoma (HCC) development. This study aimed to identify serum metabolites predictive of HCC following sustained virological response (SVR) with hepatitis C virus (HCV) treatment. Methods: Comparative metabolomics was conducted using time-course serum samples from patients who failed interferon-based therapy but subsequently achieved SVR with direct-acting antivirals (DAAs), minimizing inter-individual variability. Predictive biomarkers for post-SVR HCC were extracted from the results and validated by comparing 29 patients who developed post-SVR HCC with 58 age-matched patients who remained HCC-free during follow-up. Results: Metabolite concentrations changed more markedly after treatment in SVR cases than in non-SVR cases. Significant changes in methionine (Met), methionine sulfoxide (MetO), and ornithine (Orn) levels before and after treatment (Pre- and Post-Tx) were found only in the non-HCC group. Regression and survival analyses identified high levels of Pre- and Post-Tx Orn, Pre-Tx Met, and Post-Tx MetO as predictors of post-SVR HCC and enabled risk stratification. The integration of these metabolites with the fibrosis-4 (FIB-4) index and alpha-fetoprotein (AFP) facilitated risk stratification and discriminated between high- and low-risk patients. The Pre-Tx FIB-4/Met model and the Post-Tx AFP/MetO/Orn model identified low- and high-risk groups with 3-year HCC incidence rates of 6.4% and 81.8%, respectively. Conclusions: Serum Met, MetO, and Orn were identified as candidate biomarkers associated with post-SVR HCC development, which remains a concern in the fight against hepatitis C. Combining these metabolites with established clinical markers may improve post-SVR HCC risk stratification. Full article

Glutamine is a conditionally essential amino acid that is important for endothelial homeostasis, while endothelial cell dysfunction is associated with altered glutamine metabolism and shifts toward stress-responsive pathways. We investigated the role of glutamine and senescence-associated beta-galactosidase (SA-β-gal) activity in Ea.hy926 endothelial cells (ECs), together with supportive functional activity assays. We found that glutamine depletion induced a progressive decline in endothelial function. Specifically, glutamine-depleted ECs exhibited increased SA-β-gal activity, accompanied by impaired proliferative capacity, disrupted cellular morphogenesis, increased promyelocytic cell adhesion, and diminished ability to promote host tissue proliferation and EC morphogenesis in a zebrafish xenograft model. These findings suggest that glutamine availability is crucial for maintaining endothelial integrity and functional competence. Full article