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A smartphone-integrated Pt@Cu-HCF nanozyme-based paper sensor for on-site determination of total antioxidant capacity in marine oils.

Total antioxidant capacity (TAC) serves as a key indicator for evaluating the nutritional quality of foods. In this study, we designed a platinum-embedded copper hexacyanoferrate (denoted as Pt@Cu-HCF) nanozyme that exhibits high oxidase-like activity, efficiently catalyzing the oxidation of chromogenic substrates to generate robust colorimetric signals. Antioxidants quench hydroxyl radicals (∙OH) produced during the catalytic process, leading to a concentration-dependent suppression of the color signal. Leveraging this mechanism, a smartphone-integrated, colorimetric paper sensor for on-site TAC quantification was developed, using vitamin E as the calibration standard. The sensor was applied to determine TAC in fish oil, algal oil, and krill oil, demonstrating a linear response range of 9.78-312.5 μM and a limit of detection (LOD) of 6.41 μM. Validation using real-world marine oil samples showed excellent agreement with a commercial assay kit, confirming the reliability and practical applicability of this portable sensor for TAC measurement in complex biological matrices.

Antioxidants

Antioxidants in neoplastic cells: I. Changes in the antioxidative capacity of mouse neuroblastoma cells measured by a single-phase assay.

Cultured mouse neuroblastoma cells exhibit a striking increase in antioxidative capacity during the transition from logarithmically dividing cells to nondividing, neurite-bearing cells. Two physically separable phenomena are involved: (a) the membrane pellet of neurite-bearing cells is highly resistant to lipid peroxidation, and (b) the postmicrosomal supernatant of these cells inhibits peroxidation in rat liver mitochondria and other biological membranes. A precise, single-phase assay has been developed for assessing antioxidant levels in lipid extracts. By means of this assay, the increase in membrane resistance to lipid peroxidation has been correlated with a threefold increase in the antioxidant activity of the neuroblastoma neutral lipid fraction. This finding implies that generations of a neutral lipid antioxidant (or antioxidants) is involved in the profound increase in antioxidative capacity which occurs in differentiating neuroblastoma cells.

Animals

Effects of Acalypha australis L. Extract on Growth Performance, Antioxidant Capacity and Intestinal Microbial Composition in Weaned Piglets.

The objective of this study was to investigate the effects of Acalypha australis L. extract (ALE) on the growth performance and intestinal health in piglets. A total of 24 weaned piglets were randomly allocated to three groups: the control group (CON), which was fed a basal diet, and the ALE0.5 and ALE1.0&#x2009;groups, which were fed the basal diet supplemented with 0.5 and 1.0&#x2009;g/kg of ALE, respectively. The measured variables included growth performance, digestive enzyme activity, intestinal morphology, antioxidant capacity, and intestinal microbiota and metabolites. The results showed that, compared to the CON group, supplementation of 1.0&#x2009;g/kg ALE in the diets of weaned piglets significantly increased the ratio of gain to feed from 15 to 21 days (p&#x2009;<&#x2009;0.05), decreased the diarrhea rate from Days 15 to 21 and Days 0 to 21 (p&#x2009;<&#x2009;0.05), and increased the activities of pancreatic &#x3b1;-amylase, lipase, trypsin, and chymotrypsin, as well as duodenal &#x3b1;-amylase, lipase, and trypsin, and jejunal maltase and sucrase (p&#x2009;<&#x2009;0.05). Additionally, supplementation of 1.0 g/kg ALE in the diet significantly improved the intestinal morphology of the duodenum and jejunum, as well as the expression of intestinal barrier-related genes in the small intestine (p&#x2009;<&#x2009;0.05). Moreover, it significantly increased serum glutathione peroxidase activity and jejunal and ileal superoxide dismutase activities (p&#x2009;<&#x2009;0.05), and also significantly increased the colonic propionic acid concentration of piglets (p&#x2009;<&#x2009;0.05). The ALE supplementation increased the abundance of the colonic marker bacteria Collinsella in the piglets and influenced pathways related to amino acid metabolism, carbohydrate metabolism, and lipid metabolism. ALE can serve as a potential natural feed additive to regulate the structure of intestinal microbiota and metabolic pathways, enhance antioxidant capacity, improve intestinal health, reduce diarrhea incidence, and ultimately promote the growth performance of piglets.

Acalypha australis L. extract

Comparative metabolomic and transcriptomic profiling of flavonoid diversity and antioxidant capacity in three Isatis species.

Flavonoids are key bioactive compounds in plants with significant health benefits. This study employs an integrated multi-omics approach to investigate flavonoid diversity and antioxidant capacity across three Isatis species: I. oblongata, I. tinctoria, and I. indigotica. Metabolomic profiling identified 200 flavonoids, with glycosides being the most abundant class. I. tinctoria exhibited the highest total flavonoid content and antioxidant activity, strongly correlated with the accumulation of 53 core differential flavonoid metabolites, most of which were glycosylated derivatives. Transcriptomic analysis revealed coordinated upregulation of phenylpropanoid pathway genes and specific UDP-glycosyltransferases (UGTs) in I. tinctoria, providing a genetic basis for its enhanced glycoside production. The study establishes a clear genotype-metabolite-phenotype linkage, highlighting glycosylation as a key mechanism underlying flavonoid-driven antioxidant superiority in Isatis. Although the current evidence is primarily correlative, the consistent and strong associations across independent transcriptomic, metabolomic, and antioxidant datasets provide a robust foundation for this conclusion. These findings offer new insights into the metabolic evolution and regulatory networks of flavonoids, with implications for breeding and metabolic engineering of high-value medicinal plants.

Flavonoids

QTLs associated with phenolic acid accumulation and antioxidant activity in tropical maize.

Maize represents a significant source of phytochemicals, with phenolic acids standing out as one of the most extensively studied functional compound families. These bioactive molecules have gained attention for their potent antioxidant properties and potential contributions to human health improvement. To evaluate the segregation of phenolic compounds in maize and its genetic basis, this study was conducted to identify quantitative trait loci (QTLs) associated with major phenolic compounds and their antioxidant capacity. The mapping population comprised 100 recombinant inbred lines (RILs) derived from the cross between P84 and Kilima. Twelve traits were analyzed: free and cell wall-bound antioxidant capacity, total phenolic content, and contents of p-coumaric acid, ferulic acid, three isomers of di-ferulic acid, and three isomers of tri-ferulic acid. The RILs exhibited substantial diversity in phenolic compound profiles. In total, 19 QTLs were identified for nine traits, with the number of associated regions ranging from 1 to 5 and explaining between 2.95% and 37.48% of the phenotypic variation. This research provides substantial evidence for the co-localization of major QTLs for principal phenolic acids in maize with genomic regions harboring genes putatively related to their biosynthesis and biotic resistance. This is the first study to report QTLs associated with triferulic acids in maize. The identified regions co-localizing with biotic stress resistance genes represent targets for marker-assisted selection toward the improvement of phenolic acid accumulation in maize breeding programs.

QTLs

The R2R3-MYB transcription factor ScMYB20 negatively regulates drought and salt tolerance through a dual-repression of ScCHALCONE SYNTHASE-1 (ScCHS1)-mediated flavonoid biosynthesis in the desert moss Syntrichia caninervis.

The desert moss Syntrichia caninervis is one of the most desiccation-tolerant land plants known and provides a powerful system for dissecting the molecular foundations of extreme stress adaptation in early-diverging land lineages. The MYB transcription factor superfamily orchestrates secondary metabolism and stress signaling across plants, yet its lineage-specific evolution and mechanistic deployment in bryophytes remain poorly understood. Here, we identified 65 ScMYB genes in the S. caninervis genome and showed that the family expanded predominantly through dispersed duplication, with no detectable synteny to vascular-plant MYBs, indicating bryophyte-specific neo-functionalization. Integrating phylogenetic clustering, cis-element architecture and stress-responsive expression profiling, we pinpointed ScMYB20, a nuclear-localized, S13-subgroup R2R3-MYB that is rapidly and strongly induced by dehydration and salinity. Heterologous overexpression in Arabidopsis, together with overexpression and RNAi in S. caninervis, demonstrated that ScMYB20 negatively regulates drought and salt tolerance by suppressing antioxidant capacity, osmotic adjustment and photosynthetic performance, while concomitantly elevating ROS and MDA accumulation. Mechanistically, ScMYB20 directly binds a TAACCA motif in the ScCHS1 promoter to repress its transcription, and simultaneously sequesters the WD40 protein ScTTG1, a positive transcriptional activator of ScCHS1, thereby antagonising ScTTG1-mediated activation. Transient ScCHS1 overexpression restored flavonoid accumulation, antioxidant capacity and stress tolerance. Together, our findings define a dual-repression module (ScMYB20-ScTTG1-ScCHS1) that fine-tunes flavonoid flux under abiotic stress, and provide evolutionary and mechanistic insights into how R2R3-MYB repressors evolved to balance metabolic investment and stress survival in land plants.

Syntrichia caninervis

Influence of creatine pyruvate on newly received cattle: insights from metagenomics and metabolomics.

Transport stress is a critical factor affecting the health and growth performance of beef cattle, potentially leading to oxidative stress, inflammation, and metabolic disorders. Creatine pyruvate (CrPyr), as a potential stress alleviator, has unclear mechanisms of action. We monitored the growth of 17 Simmental calves (control, n&#x2009;=&#x2009;8; CrPyr, n&#x2009;=&#x2009;9) over 30 days post-transportation, collecting rumen and blood samples on days 1/4, and 30. This study aims to investigate the effects of CrPyr on the growth performance, rumen microbiome, and metabolome of calves subjected to transport stress. Results showed that CrPyr increased average daily gain and antioxidant capacity, while reducing the level of stress hormones and inflammation. In the 4 days post-transport, CrPyr mainly increases Ruminococcus abundance to boost ruminal nitrogen metabolism, providing substrates for microbial protein synthesis. CrPyr also provides energy for the proliferation of Ruminococcus by regulating ATP synthesis genes (ATPVC) and enriching purine metabolism products. Meanwhile, it strengthens the host's amino acid metabolism, especially aspartate, to enhance antioxidative capacity. By day 30, CrPyr primarily boosts Prevotella abundance to regulate VFA synthesis, supplying host energy. It regulates the ATP synthesis gene ATPF0A and enriches purine metabolism products, supporting Prevotella growth. Increased citric acid and ATP levels further aid host growth. The findings distinctly demonstrate that the mechanisms by which CrPyr alleviates transport stress through the regulation of the rumen microbiome and metabolome, and confirms that its effects are time-dependent. These findings provide a theoretical basis for the development of stress-alleviation strategies based on CrPyr and hold significant implications for enhancing the health and production performance of beef cattle.

Animals

Free polyphenols and multi-omics traits underlying antioxidant variation across Paeonia lactiflora leaf cultivars.

Leaves of Paeonia lactiflora are underutilized by-products with potential as natural antioxidant sources. In this study, 18 cultivars were evaluated for phytochemical composition and in vitro antioxidant capacity. Total phenolic content correlated strongly with DPPH and ABTS activities, and the comprehensive antioxidant index identified 'Coral Charm' and 'Hangshao' as representative high- and low-antioxidant cultivars, respectively. Untargeted metabolomics detected 2677 metabolites and identified 908 differential metabolites between the two cultivars. Targeted phenolic profiling quantified 27 compounds, among which 11 differed significantly between the two cultivars. Catechin and epicatechin were enriched in 'Coral Charm', with contents of 6.62 and 0.397&#xa0;ng/mg, respectively, compared with 0.012 and 0.002&#xa0;ng/mg in 'Hangshao'. (+)-Dihydroquercetin was also more abundant in 'Coral Charm', while caffeic acid showed an upward trend. Proteomic analysis identified 423 differentially expressed proteins, mainly associated with secondary metabolite biosynthesis, redox homeostasis, and central carbon metabolism. Integrated analysis identified pyruvate metabolism as the only pathway significantly enriched in both metabolomic and proteomic datasets. Molecular docking predicted favorable binding between representative phenolics and selected proteins. These findings link cultivar-dependent antioxidant variation in peony leaves with free-phenolic accumulation and pathway-level metabolic differences, supporting the selection and utilization of antioxidant-rich peony leaf resources.

Antioxidants

Pre-transport dietary chitosan improves the physiological robustness of juvenile largemouth bass (Micropterus salmoides) by modulating antioxidant and inflammatory responses.

The acute stress caused by long-distance transport can lead to oxidative damage, immune dysfunction, and health deterioration in fish. This study evaluated dietary chitosan as a pre-transport nutritional strategy for juvenile largemouth bass (Micropterus salmoides). Five experimental diets contained chitosan at 0, 2.5, 5.0, 7.5, or 10.0&#x202f;g/kg, designated as p0, p25, p50, p75, and p100, respectively, for 56&#x202f;d. The effects of dietary chitosan were evaluated using growth performance, feed utilization, digestive function, antioxidant capacity, nonspecific immunity, and resistance to Aeromonas hydrophila infection. Then, fish from the p0 and p50 groups underwent a 12-h transport stress test, with samples collected before, during, and 7&#x202f;d after transport. Dietary chitosan improved most of these parameters. Among the treatment groups, p50 and p75 showed the best overall performance. The dose-response analysis further indicated that the appropriate dietary inclusion range was 5.0-7.5&#x202f;g/kg. Under transport stress, fish in the p50 group exhibited more stable antioxidant enzyme responses and lower lipid peroxidation, as indicated by reduced MDA levels. Consistent with these enzyme responses, antioxidant-related genes remained relatively stable. At the same time, expression patterns related to the Nrf2-Keap1 and NF-&#x3ba;B signaling pathways suggested that 5.0&#x202f;g/kg chitosan alleviated transport-induced oxidative damage and inflammation. Dietary chitosan also attenuated pro-inflammatory gene induction and altered the temporal expression patterns of anti-inflammatory genes. Overall, 5.0-7.5&#x202f;g/kg dietary chitosan is suitable for juvenile largemouth bass, and 5.0&#x202f;g/kg may serve as an effective pre-transport dietary inclusion level.

Animals

Integrated widely targeted metabolomics and GC-IMS reveal dynamic flavor, nutritional, functional, and metabolic profiles in macadamia kernels during processing.

Different processing stages influence the color, flavor, and antioxidant activities of macadamia kernels. However, the biochemical mechanisms that occur during processing are not well known. This study integrated widely targeted metabolomics (UPLC-MS/MS) with GC-IMS to systematically characterize non-volatile and volatile compounds in macadamia kernels across key three sample groups: fresh kernels (FMN), low-temperature-dried kernels (DMN), and roasted kernels (BMN). A total of 622 non-volatile metabolites and 52 volatile compounds were identified. Low-temperature drying promoted the accumulation of phenolic acids and flavonoids, enhancing antioxidant capacity. Roasting degraded heat-sensitive nutrients but generated flavor compounds via Maillard reaction and lipid oxidation, shifting aroma from green to nutty notes. Nutritional assessment confirmed that roasting significantly reduced antioxidant activities and bile acid binding capacity. Pearson correlation analysis verified the key metabolite-antioxidant relationships. These findings provide critical insights into metabolic dynamics during nut processing and establish a scientific basis for optimizing thermal processing strategies.

Metabolomics

The transcriptional regulator CasR controls mycobacterial antioxidant defense and biofilm formation via multiple direct targets.

AIMS: The antioxidant defense system of Mycobacterium tuberculosis is critical for pathogenicity and persistence within macrophages, yet the regulatory networks remain poorly understood. This study aims to elucidate the molecular mechanism by which the transcription factor CasR regulates antioxidant defense in mycobacteria through delineation of the regulatory axis linking CasR activity, target gene expression, and the antioxidant phenotype. METHODS AND RESULTS: Using Mycobacterium smegmatis as a model organism, we demonstrate that overexpression of CasR renders the bacteria significantly susceptible to hydrogen peroxide. Electrophoretic mobility shift assay (EMSA) and &#x3b2;-galactosidase reporter analyses reveal that CasR directly binds and represses the promoter of cyp144, an uncharacterized cytochrome P450-encoding gene. Deletion of casRMsmreduces biofilm formation, consistent with the expected derepression of cyp144Msm, a gene that negatively regulates both biofilm and oxidative stress tolerance. EMSA and &#x3b2;-galactosidase activity assays also demonstrate that CasR negatively regulates antioxidant gene katGI, suggesting that CasR exerts a broader, global regulatory role within the mycobacterial antioxidant defense network. Furthermore, we identify isoleucine 18 as a critical residue for the DNA-binding and regulatory function of CasR. CONCLUSION: This study establishes CasR as a pleiotropic transcriptional regulator that directly controls multiple antioxidant genes, including cyp144 and katGI, in mycobacteria. We report a previously unrecognized role for a cytochrome P450 family member in suppressing bacterial antioxidant capacity, as cyp144 overexpression reduces biofilm formation. These findings provide a valuable reference for further investigation into mycobacterial antioxidant mechanisms and identify CasR and Cyp144 as potential targets for the development of anti-tuberculosis drugs.

Biofilms

Association between sirtuin 1 and markers of oxidative stress in master athletes.

BACKGROUND: Lifelong training in master athletes confers protective effects, promoting higher sirtuin levels and enhanced antioxidant capacity. Although Sirtuin 1 (SIRT1) is well studied, no previous study has examined the relationship between circulating SIRT1 levels and antioxidant defense variables in master athletes. PURPOSE: To compare and analyze the relationships between circulating levels of SIRT1 and variables related to antioxidant defense in master athletes (MA) and untrained middle-aged individuals (UMA). METHODS: Male MA (n&#x2009;=&#x2009;42; 51.62&#x2009;&#xb1;&#x2009;7.33 years; &#x2265;10 years of training and competition in running) and UMA (n&#x2009;=&#x2009;15; 47.73&#x2009;&#xb1;&#x2009;8.52 years) were evaluated. Venous blood samples were collected for biochemical analyses of SIRT1, antioxidant enzymes, TBARS and F2-isoprostanes, 8-OHdG, and redox balance indexes. RESULTS: MA showed higher levels of SIRT1 (18.22&#x2009;&#xb1;&#x2009;4.53 vs. 6.08&#x2009;&#xb1;&#x2009;2.11 ng/mL; p&#x2009;<&#x2009;0.0001), as well as of SOD, CAT, and GSH (p&#x2009;<&#x2009;0.001), indicating a more favorable antioxidant profile. After adjustment for body fat percentage, differences in SOD, CAT, GSH and TBARS, remained significant. SIRT1 was positively correlated with SOD (r&#x2009;=&#x2009;0.279; p&#x2009;=&#x2009;0.031), CAT (r&#x2009;=&#x2009;0.485; p&#x2009;<&#x2009;0.001), GSH (r&#x2009;=&#x2009;0.476; p&#x2009;<&#x2009;0.001) and CAT/8-OHdG (r&#x2009;=&#x2009;0.430; p&#x2009;=&#x2009;0.032), and negatively correlated with TBARS (r&#x2009;=&#x2009;-&#x2009;0.518; p&#x2009;<&#x2009;0.001). CONCLUSION: Master athletes exhibited higher circulating SIRT1 concentrations and a more favorable systemic redox profile than untrained individuals, with SIRT1 being associated with markers of antioxidant defense, lipid peroxidation, and redox balance.

Aging

Dietary naringenin modulates antioxidant status and hepatic lipid deposition in marine medaka (Oryzias dancena) fed a high-fat diet.

High-fat diets (HFDs) are widely used in aquaculture to improve growth and feed efficiency; however, prolonged feeding can disrupt lipid metabolism, induce oxidative stress, and impair physiological homeostasis. This study evaluated the protective effects of dietary naringenin against HFD-induced physiological alterations in the marine medaka Oryzias dancena. Fish were randomly assigned to one of four dietary treatments and fed the respective experimental diets for 45&#xa0;days: a normal-fat diet (NFD, 8% crude lipid), a high-fat diet (HFD, 15% crude lipid), or an HFD supplemented with either 0.075% or 0.15% naringenin. Compared with the NFD group, HFD feeding impaired antioxidant status, altered the expression of genes associated with antioxidant defence and lipid metabolism, and promoted hepatic lipid accumulation. Dietary naringenin, particularly at 0.15%, mitigated these adverse effects by restoring muscle superoxide dismutase activity, enhancing total antioxidant capacity, reducing lipid peroxidation, partially normalizing the expression of lipid metabolism-related genes, and alleviating hepatic lipid vacuolation. These findings indicate that dietary naringenin improves antioxidant defence and helps maintain lipid metabolic homeostasis under high-fat feeding conditions, highlighting its potential as a functional dietary additive for aquaculture.

Animals

GCLC desuccinylation regulated by oxidative stress protects human cancer cells from ferroptosis.

Tumor cells evolve strong antioxidant capacities to counteract the abnormal high level of reactive oxygen species (ROS) in the tumor microenvironment. Glutamate-cysteine ligase catalyzing subunit (GCLC) for synthesis of antioxidant glutathione (GSH) represents the key enzyme to maintain redox homeostasis of tumor cells, however, whether its activity is regulated by posttranslational modifications, such as succinylation, remains to be clarified. Here, we demonstrate the existence of succinylation modification on GCLC by in vitro and in vivo assays. NAD-dependent deacetylase Sirtuin-2 (SIRT2) serves as the desuccinylase and catalyzes GCLC desuccinylation at sites of K38, K126, and K326. Specifically, GCLC directly interacts with SIRT2, which can be substantially enhanced upon ROS treatment. This strengthened association results in GCLC desuccinylation and activation, consequently promoting GSH synthesis and rendering cancer cells resistant to ferroptosis induction. Depletion of SIRT2 decreases total GSH level and meanwhile increases the cellular susceptibility to ferroptosis, which can mostly be rescued by introducing wild-type GCLC, but not its 3K-E mutant. We further demonstrated that histone acetyltransferase P300 serves as the succinyltransferase of GCLC, and their association is remarkably decreased after ROS treatment. Thus, SIRT2-regulated GCLC succinylation represents an essential signaling axis for cancer cells to maintain their redox balance in coping with oxidative stress-induced ferroptosis.

Humans

Eugenol-Derived Cytoprotective Action Against Dityrosine-Induced Oxidative Stress in Mice Liver via Akt/Nrf2/ARE Signaling Pathway.

Dityrosine (Dityr), a byproduct of protein oxidation in protein-rich food, induces oxidative stress, inflammation, and apoptosis, jeopardizing human health. Eugenol (EUG), a natural compound with antioxidative and anti-inflammatory properties, was investigated for its protective effects against Dityr-induced hepatotoxicity in this work. In this study, in vivo and in vitro analyses demonstrated EUG's protective effects against Dityr-induced hepatotoxicity. EUG significantly attenuated oxidative stress markers, inflammatory infiltration, fibrotic progression, and apoptotic signaling in mice liver tissues. Mechanistically, EUG activated the Akt/NF-E2-related factor 2/antioxidant response element (Akt/Nrf2/ARE) pathway, enhancing cellular antioxidant capacity while suppressing pro-inflammatory cytokine release. In HepG2 cells, EUG treatment effectively counteracted Dityr-induced ROS overproduction and cell death through Nrf2-mediated antioxidant upregulation. In conclusion, our findings indicate that EUG effectively mitigates Dityr-induced oxidative stress via the Akt/Nrf2/ARE pathway, and this antioxidative impact further inhibits inflammation and apoptosis. These effects ultimately ameliorate liver function impairment caused by Dityr.

Animals

The dirigent protein MsDIR6 functions in drought tolerance and modulates reactive oxygen species scavenging and secondary metabolite biosynthesis in alfalfa.

Alfalfa (Medicago sativa L.) is a globally significant forage crop essential for ensuring global food security. However, soil water deficit leads to a substantial decline in its yield, posing a severe threat to sustainable forage production. Dirigent (DIR) proteins play important roles in lignan biosynthesis and plant stress responses. Here, we identified 52 MsDIR genes in alfalfa through a genome-wide analysis, and screened MsDIR6 as a key candidate gene associated with drought tolerance. The results of qRT-PCR showed that MsDIR6 transcription was significantly induced by drought stress in alfalfa. MsDIR6 was preferentially expressed in roots and leaves, and its protein was localized in the nucleus and plasma membrane. Heterologous expression of MsDIR6 in yeast improved tolerance to mannitol-triggered osmotic stress. Heterologous overexpression of MsDIR6 in Arabidopsis significantly increased seed germination rate, seedling survival rate, and antioxidant capacity under drought stress, while improving leaf water-holding capacity by regulating stomatal movement. In transgenic alfalfa hairy roots, MsDIR6 alleviated drought-induced growth inhibition and enhanced reactive oxygen species (ROS) scavenging mediated by the antioxidant defense system under drought stress. Transcriptomic analysis revealed that MsDIR6 activated key genes in the phenylpropanoid and flavonoid biosynthesis pathways, which are crucial for ROS scavenging during drought adaptation. Additionally, we observed elevated flavonoid and lignin contents in MsDIR6-overexpressing alfalfa. Collectively, our findings offer novel insights into alfalfa's drought tolerance mechanisms and identify MsDIR6 as a promising genetic resource for molecular breeding strategies to improve this vital forage crop.

Alfalfa

Antioxidants and the cardiomyopathy of Mg-deficiency.

For several decades the animal models of Mg-deficiency have been studied with particular attention to the cardiomyopathy that develops due to dietary deficiency. In recent years we have studied the effects of nutrients and drugs with antioxidant properties on the development of the cardiomyopathy. We have found that treatment of the Mg-deficient animals with alpha-tocopherol, a naturally-occurring antioxidant, significantly diminishes the number and size of lesions. In addition, treatment with lipophilic drugs with antioxidant properties (probucol, propranolol) or water-soluble drugs that scavenge hydroxyl radicals (captopril, epicaptopril), also provided significant protection. In view of these findings, we suggest that chronic hypomagnesemia results in a pro-inflammatory condition leading to excessive production of oxygen-derived free radicals. Subsequently, the tissue antioxidant capacity is overwhelmed and oxidative tissue destruction results.

Angiotensin-Converting Enzyme Inhibitors

Rumen microbiota-associated stress alleviation by creatine pyruvate in newly received cattle: a multi-omics study.

BACKGROUND: Stress experienced by newly received cattle is a significant challenge in the beef industry, frequently resulting in weakened immune responses and impaired growth. The rumen microbiota is essential to host health, and its imbalance can exacerbate stress. This study investigates the mechanisms by which creatine pyruvate (CrPyr) mitigates stress in newly received cattle through multi-omics approaches, including metagenomics, metabolomics, in vitro and in vivo experiments, and rumen microbiota transplantation (RMT) in mice. RESULTS: Our results revealed that CrPyr significantly reduces stress-related hormones (cortisol and adrenocorticotropic hormone) and inflammatory markers (IL-6, IL-1&#x3b2;, and TNF-&#x3b1;), and enhanced antioxidant capacity (SOD: 57.38 versus 46.93&#xa0;U/mL, P&#x2009;<&#x2009;0.05; GSH-Px: 305.87 versus 217.07&#xa0;U/mL, P&#x2009;<&#x2009;0.05; T-AOC: 9.62 versus 7.66&#xa0;U/mL, P&#x2009;<&#x2009;0.05). Metagenomic analysis demonstrated that CrPyr increased Prevotella abundance, a key rumen bacterium involved in volatile fatty acid (VFA) production, and enriches metabolic pathways associated with energy metabolism (ATP synthesis, and pyruvate metabolism) and antioxidant defense (glutathione metabolism, FC&#x2009;=&#x2009;1.08, P&#x2009;<&#x2009;0.05). In vitro and in vivo experiments, as well as RMT studies in mice, further validate these findings, demonstrating that CrPyr promote VFA synthesis and increased ATP production through the electron transport phosphorylation pathway. CONCLUSIONS: CrPyr modulates the abundance of ruminal Prevotella in transport-stressed cattle to enhance glutathione and VFA metabolism and to accelerate ATP and nucleotide synthesis, thereby alleviating stress in newly received cattle. This multimodal approach established CrPyr as an effective nutritional intervention that improves rumen function and increases livestock productivity. Video Abstract.

Animals