Oxidative Activity Research Articles

Therapeutic Modulation of Arginase with nor-NOHA Alters Immune Responses in Experimental Mouse Models of Pulmonary Tuberculosis including in the Setting of Human Immunodeficiency Virus (HIV) Co-Infection.

L-arginine metabolism is strongly linked with immunity to mycobacteria, primarily through the antimicrobial activity of nitric oxide (NO). The potential to modulate tuberculosis (TB) outcomes through interventions that target L-arginine pathways are limited by an incomplete understanding of mechanisms and inadequate in vivo modeling. These gaps in knowledge are compounded for HIV and Mtb co-infections, where activation of arginase-1 due to HIV infection may promote survival and replication of both Mtb and HIV. We utilized in vitro and in vivo systems to determine how arginase inhibition using Nω-hydroxy-nor-L-arginine (nor-NOHA) alters L-arginine pathway metabolism relative to immune responses and disease outcomes following Mtb infection. Treatment with nor-NOHA polarized murine macrophages (RAW 264.7) towards M1 phenotype, increased NO, and reduced Mtb in RAW macrophages. In Balb/c mice, nor-NOHA reduced pulmonary arginase and increased the antimicrobial metabolite spermine in association with a trend towards reduced Mtb CFU in lung. In humanized immune system (HIS) mice, HIV infection increased plasma arginase and heightened the pulmonary arginase response to Mtb. Treatment with nor-NOHA increased cytokine responses to Mtb and Mtb/HIV in lung tissue but did not significantly alter bacterial burden or viral load. Our results suggest that L-arginine pathway modulators may have potential as host-directed therapies to augment antibiotics in TB chemotherapy.

Investigation on the Tea Polyphenol/Swelling Gels to Inhibit Coal Spontaneous Combustion: An Experimental Study

ABSTRACT Developing new fire-fighting material is most significant for effective prevention and control of coal spontaneous combustion. To enhance the flame-retardant performance of the gel, the tea polyphenol/swelling gels are developed using a water-soluble polymerization method. Thermogravimetric analysis, programmed temperature experiments, and Fourier-transform infrared spectroscopy are used to reveal the structural characteristics, microscopic morphology, and thermal stability of the gel. Experimental testing the tea polyphenol/swelling gels’ water absorption, water retention, and reusability as well as their inhibitory effect on coal spontaneous combustion. The results showed that the prepared tea polyphenol/swelling gels exhibited a porous three-dimensional network structure, with a maximum swelling ratio of 607.2 g/g and a salt absorption rate of 121.4 g/g. After the testing coal sample is treating by the tea polyphenol/swelling gels, its CO production rate is sharply decreased, but the corresponding ignition point temperature and flame-retardant rate are significantly increased. The activation energy in the first stage is increased by 32.2 kJ·mol−1, in the second stage by 4.0 kJ·mol−1, and in the third stage by 23.2 kJ·mol−1. Additionally, the active functional groups such as hydroxyl and methyl in the coal are also reduced by the treatment of tea polyphenol/swelling gels. Correlation analysis indicate that the inhibition effect of coal spontaneous combustion can be achieved by reducing -OH, CH3/CH2 groups, while the increasing of C = C, C- O, C- H functional groups in the coal. Moreover, the tea polyphenol/swelling gels performing the characteristics of excellent water absorption, inhibiting coal spontaneous combustion by absorbing heat, covering the coal microstructure, and inhibiting the oxidative activity of coal molecules. This study can provide theoretical guidance for the application of swelling gels in inhibiting coal spontaneous combustion.

Enhancing Rubber Industry Wastewater Treatment through an Integrated AnMBR and A/O MBR System: Performance, Membrane Fouling Analysis, and Microbial Community Evolution.

This study explores the effectiveness of an integrated anaerobic membrane bioreactor (AnMBR) coupled with an anoxic/oxic membrane bioreactor (A/O MBR) for the treatment of natural rubber industry wastewater with high sulfate, ammonia, and complex organic contents. This study was conducted at the lab-scale over a duration of 225 days to thoroughly investigate the efficiency and sustainability of the proposed treatment method. With a hydraulic retention time of 6 days for the total system, COD reductions were over 98%, which reduced the influent from 22,158 ± 2859 mg/L to 118 ± 74 mg/L of the effluent. The system demonstrates average NH3-N, TN, and total phosphorus (TP) removal efficiencies of 72.9 ± 5.7, 72.8 ± 5.6, and 71.3 ± 9.9, respectively. Despite an average whole biological system removal of 50.6%, the anaerobic reactor eliminated 44.9% of the raw WW sulfate. Analyses of membrane fouling revealed that organic fouling was more pronounced in the anaerobic membrane, whereas aerobic membrane fouling displayed varied profiles due to differential microbial and oxidative activities. Key bacterial genera, such as Desulfobacterota in the anaerobic stage and nitrifiers in the aerobic stage, are identified as instrumental in the biological processes. The microbial profile reveals a shift from methanogenesis to sulfide-driven autotrophic denitrification and sulfammox, with evidence of an active denitrification pathway in anaerobic/anoxic conditions. The system showcases its potential for industrial application, underpinning environmental sustainability through improved wastewater management.

Identification of a longevity gene through evolutionary rate covariation of insect mito-nuclear genomes.

Oxidative phosphorylation, essential for energy metabolism and linked to the regulation of longevity, involves mitochondrial and nuclear genes. The functions of these genes and their evolutionary rate covariation (ERC) have been extensively studied, but little is known about whether other nuclear genes not targeted to mitochondria evolutionarily and functionally interact with mitochondrial genes. Here we systematically examined the ERC of mitochondrial and nuclear benchmarking universal single-copy ortholog (BUSCO) genes from 472 insects, identifying 75 non-mitochondria-targeted nuclear genes. We found that the uncharacterized gene CG11837-a putative ortholog of human DIMT1-regulates insect lifespan, as its knockdown reduces median lifespan in five diverse insect species and Caenorhabditis elegans, whereas its overexpression extends median lifespans in fruit flies and C. elegans and enhances oxidative phosphorylation gene activity. Additionally, DIMT1 overexpression protects human cells from cellular senescence. Together, these data provide insights into the ERC of mito-nuclear genes and suggest that CG11837 may regulate longevity across animals.

Homo- and Heterogeneous Benzyl Alcohol Catalytic Oxidation Promoted by Mononuclear Copper(II) Complexes: The Influence of the Ligand upon Product Conversion.

The catalytic properties of three copper complexes, [Cu(en)2](ClO4)2 (1), [Cu(amp)2](ClO4)2, (2) and [Cu(bpy)2](ClO4)2 (3) (where en = ethylenediamine, amp = 2-aminomethylpyridine and bpy = 2,2'-bipyridine), were explored upon the oxidation of benzyl alcohol (BnOH). Maximized conversions of the substrates to their respective products were obtained using a multivariate analysis approach, a powerful tool that allowed multiple variables to be optimized simultaneously, thus creating a more economical, fast and effective technique. Considering the studies in a fluid solution (homogeneous), all complexes strongly depended on the amount of the oxidizing agent (H2O2), followed by the catalyst load. In contrast, time seemed to be statistically less relevant for complexes 1 and 3 and not relevant for 2. All complexes showed high selectivity in their optimized conditions, and only benzaldehyde (BA) was obtained as a viable product. Quantitatively, the catalytic activity observed was 3 > 2 > 1, which is related to the π-acceptor character of the ligands employed in the study. Density functional theory (DFT) studies could corroborate this feature by correlating the geometric index for square pyramid Cu(II)-OOH species, which should be generated in the solution during the catalytic process. Complex 3 was successfully immobilized in silica-coated magnetic nanoparticles (Fe3O4@SiO2), and its oxidative activity was evaluated through heterogenous catalysis assays. Substrate conversion promoted by 3-Fe3O4@SiO2 generated only BA as a viable product, and the supported catalyst's recyclability was proven. Reduced catalytic conversions in the presence of the radical scavenger (2,2,6,6-tetrametil-piperidi-1-nil)oxil (TEMPO) indicate that radical and non-radical mechanisms are involved.

Metabolites of Culinary-medicinal Mushroom Hericium erinaceus Showed Anti-neuroinflammatory Activity in BV2 Cells and Anti-H2O2-induced Oxidative Stress Activity in SH-SY5Y Cells

Background: Hericium erinaceus is a versatile mushroom with potential therapeutic benefits. A variety of bioactive compounds have been found in this mushroom that have anti-ulcer, antiinflammatory, immunomodulatory, and blood sugar and lipid regulating effects. Objectives: The aim is to isolate and characterize compounds from the rice medium of H. erinaceus and evaluate their potential therapeutic effects on oxidative stress-associated diseases. Methods: Fifteen compounds were isolated and characterized using NMR spectra and ESI-MS. The effects of compounds 3 and 7 on LPS-induced nitric oxide (NO) generation in BV2 cells and H2O2- induced cytotoxicity in SH-SY5Y cells were investigated. The regulation of nitric oxide production and apoptosis-associated proteins Bcl-2 and Bax were also examined. Results: Compounds 3 and 7 exhibited potent inhibitory effects on LPS-induced NO generation in microglial cells and significant resistance to H2O2-induced cytotoxicity in neuronal cells. Molecular docking simulations demonstrated the interaction of compounds 3 and 7 with iNOS and Bax, respectively. Western blot analysis revealed that 7 inhibited NO production and regulated the expression of Bax and Bcl-2, suggesting a protective effect against H2O2-induced apoptosis. Conclusion: Compounds 3 and 7 isolated from H. erinaceus are potential therapeutic candidates for oxidative stress-associated diseases, possibly through their regulation of nitric oxide production and apoptosis-related proteins. Further investigations are warranted to elucidate their mechanisms of action and therapeutic potential.

Thermocatalytic oxidation potential of cobalt(II,III) oxide against gaseous formaldehyde in relation to hydrothermal synthesis temperature

The catalytic activity of various transition metal oxides has been reported to be tuned by controlling their synthesis conditions. In this perspective, the thermocatalytic oxidation performance of cobalt(II,III) oxides (Co3O4) against formaldehyde (FA) is studied in relation to the temperature selected for their hydrothermal synthesis (e.g., 30 (as room temperature (RT)), 60, 120, and 250℃) with the corresponding sample codes as Co3O4-RT, Co3O4-60, Co3O4-120, and Co3O4-250, respectively. The best performing Co3O4-RT records the lowest T90 (temperature required to obtain 90 % conversion) for 50 ppm FA at 72 °C when operated at 0 % relative humidity (RH), 30 mg (catalyst mass: mcat), and 100,000 mL g-1h−1 (weight hourly space velocity). The performance of Co3O4-RT, if assessed in terms of reaction kinetic rate (r) at XFA = 10 %, is 2.02E-02 mmol g-1h−1. According to X-ray photoelectron spectroscopy and temperature programmed characterization analysis, the catalytic activities of Co3O4-RT improve greatly through the synergistic combination of diverse factors (e.g., high Co3+ content, abundant oxygen vacancies (OVs) and surface adsorbed oxygen (Oβ) species, and good surface lattice oxygen (Oα) mobility). The analysis of in-situ diffuse reflectance infrared Fourier transform spectroscopy indicates that the FA should be oxidized into water (H2O) and carbon dioxide (CO2) via dioxymethylene (DOM) and formate (HCOO–) as reaction intermediates. The density functional theory simulations suggest the (111) surface of Co3O4 to be catalytically active against FA. The output of this research is expected to help establish effective strategies for designing high-performance transition metal oxide catalysts for the catalytic oxidation of FA.

The role of Phanerochaete australis in enhancing defense activity against Magnaporthe oryzae in upland rice

ABSTRACT The inclusion of biological control in the integrated management of rice blast (Magnaporthe oryzae [Mo]) reduces pesticide application. Phanerochaete australis (Pha) has been shown to be a potential inducer of resistance to rice blast. Pha was isolated saprophytically from the rice phylloplane and studied for its interaction with Mo in the defense process of upland rice plants against the pathogen attack. Investigating the Pha × Mo interaction in a completely randomized design, the suppression of leaf blast and the epidemiological components of disease development were quantified in vivo, whereas the physiological and biochemical aspects, as defense enzymes and oxidative complex components, were evaluated in vitro during the induction of resistance. In the Pha × Mo interaction, it was found that seed treatment can significantly reduce disease severity by up to 93%, increase the photosynthetic apparatus, mobilize photoassimilates to the defense system, intensify defense enzyme and oxidant complex activities (chitinase [CHI], β-1,3-glucanase [GLU], lipoxygenase [LOX], phenylalanine ammonia-lyase [PAL], poliphenoloxidase [PPO], peroxidase [POX], catalase [CAT], cuperoxide dismutase [SOD]), decrease phenolic compounds (TPCs), and increase photosynthetic pigment levels compared with the negative control (Mo). When treating the seed, we are referring to an induction process where there is no physical contact between the pathogens. The enzymes produced by the interaction between the microorganisms validate this process; thus, Pha acts as an inducer of resistance to upland rice plants challenged with Mo.

The chemistry of HNO-releasing compounds

HNO (azanone or nitroxyl), formally a product of the one-electron reduction of a nitric oxide, exhibits diverse and unique biological activity. The chemistry, biochemistry, and biological/pharmacological effects of HNO have been studied extensively. Due to rapid dimerization and hence short lifetime in solutions, in chemical and biological studies HNO is typically produced in situ from its thermal donors. To date, a great variety of chemical HNO donors have been synthesized, characterized, and utilized in biological studies. Here, we discuss the chemistry of HNO-releasing compounds, with the emphasis on the complexity of the proposed reaction mechanisms.

A novel polysaccharide of Undaria pinnatifida: Structural characterization, carboxymethylation and hypoglycemic activity in vivo

A new polysaccharide (UPP) was isolated and purified from Undaria pinnatifida with a low molecular weight of 8.34 kDa. The UPP was modified to obtain carboxymethylated polysaccharide (CM-UPP). UPP and CM-UPP were characterized by FT-IR, Ion chromatography, Congo red, DSC, SEM and NMR, and their hypoglycemic activity in vivo was investigated using the STZ-induced diabetes mice model. UPP mainly contained Ara, Gal, Glc and Man at a molar ratio of 0.18: 0.13: 2.06: 1, and CM-UPP added two alduronic acids including GalA and GlcA. CM-UPP had been prepared successfully and the carboxymethylation reaction might occur partially at the C-2 and C-4 position. There were no triple helix structures in both UPP and CM-UPP. In vivo hypoglycemic activity studies showed that both UPP and CM-UPP could alleviate symptoms of high blood glucose, improve blood lipid level, oxidative stress state and liver glycolytic enzyme activity in diabetic mice. Under the same dose, CM-UPP showed a more significant effect than UPP. These results indicated that carboxymethylation was an effective way to enhance the hypoglycemic activitiy of polysaccharide. UPP and CM-UPP could be potential therapeutic agents of T2DM.

Polluted water from a storage dam (Villa Victoria, méxico) induces oxidative damage, AChE activity, embryotoxicity, and behavioral changes in Cyprinus carpio larvae

The Villa Victoria dam is one of the most important storage reservoirs in Mexico since it distributes water to more than 20 million inhabitants in the Metropolitan Zone of Mexico City. In this dam, the common carp (Cyprinus carpio) is an important food resource for the inhabitants, so the aim of this work was to evaluate the oxidative damage (lipoperoxidation, oxidized proteins, antioxidant enzymes activity and gene expression), AChE, embryotoxicity and behavioral changes in C. carpio embryos and larvae exposed to water from Villa Victoria dam for 24, 48, 72 and 96 h. The embryotoxicity was evaluated trough the General Morphology Score (GMS) and the teratogenic index. Behavioral changes in basal locomotor activity and thigmotaxis were evaluated in a DanioVision, Noldus ™. An increase in lipid and protein oxidation as well as modification of CAT, SOD and GPx enzymatic activity was observed during the exposure times. The GMS indicated a low development in the embryos, the teratogenic index was less than 1, however teratogenic effects as yolk edema, fin malformation, head malformation and scoliosis were observed. In parallel, an increase in AChE activity and gene expression was observed reflecting changes in distance traveled of the basal locomotor activity and thigmotaxis at the sampling points. In conclusion, pollutants in water from Villa Victoria dam caused oxidative damage, changes in SOD, CAT, GPx and AChE activity as well as embryotoxicity and modifications in the behavior of C. carpio larvae. This study demonstrates the need to implement restoration programs for this reservoir since, contamination in the Villa Victoria dam could eventually endanger aquatic life and human health.

Enhancing drought tolerance in broccoli (Brassica oleracea L.) through melatonin application: Physiological and biochemical insights into growth, photosynthesis, and antioxidant defense mechanisms

Broccoli is a well-known and high-value vegetable crop for its abundance of antioxidants and minerals. Despite its popularity, its production faces significant challenges from various abiotic stressors, particularly drought stress. Melatonin a multifunctional molecule within plants modulates environmental stresses including drought stress. Therefore, the current study aimed to evaluate the effect of melatonin application (0 and 100 μM) on broccoli under 100% field capacity (FC) (well-watered) and drought stress (50% field capacity). Foliar application of melatonin helped overcome drought-induced losses and enhanced plant height (23.72%), root length (43.47%), total chlorophyll contents (46%), carotenoids (60%) and yield (34.23%), glycine betaine (GB) (77.7%), whereas reducing the oxidative activities of hydrogen peroxide (H2O2) (20%) and leaf water potential (LWP) (33.35%) in broccoli plants. Antioxidant activities, i.e., superoxide dismutase (SOD), peroxide (POD), catalase (CAT), and ascorbate (APX) were further enhanced under melatonin treatment with 28.53%, 26.10%, 35.26%, and 33.33% respectively. Melatonin application significantly increased gas exchange characteristics by increasing stomatal conductance. Pearson correlation matrix and biplot were developed for the determination of trait association and treatment performance. Exogenous melatonin application decreased the oxidative damage brought on by the drought and increased the yield of broccoli.

Isolation of flavonoids from Tagetes patula(French Marigold) flowers: Cytotoxic and oxidant activity in human cervical carcinoma cells

Tagetes patula, known as French Marigold, belongs to the family Asteraceae. Human papillomavirus infection is considered one of the causes of cervical cancer. This study assessedthe cytotoxic activity and intracellular oxidative capacity of compounds isolated from extract of T. patulaflowers as anti-cancer cervical agents. Fraction F6 of n-butanol extract was subjected to column chromatography and HPLC-ESI-MS. The isolated compounds of T. patulawere used to examine cytotoxic activity and the production of total reactive oxygen species in SiHa and HeLa cells; the cells were also characterized using scanning electron microscopy. Patulitrin was cytotoxic to SiHa and HeLa cells. An increase in ROS production was observed at different times of treatment of cells with patuletin and patulitrin. Scanning electron microscopy showed morphological changes in SiHa and HeLa cells. Thus, compounds isolated from T. patulahave great treatment potential against cervical cancer.

Aqueous extract-mediated green synthesis of CuO nanoparticles: Potential anti-tuberculosis agents.

The emergence of drug-resistant strains in tuberculosis treatment underscores the urgency for novel therapeutic approaches. This study investigates the anti-tuberculosis activity of green-synthesized copper oxide (CuO) nanoparticles (NPs) using garlic and astragalus extracts. The physicochemical characterization of the nanoparticles confirms successful synthesis, followed by assessment of their antibacterial properties and safety profile. Rats infected with Mycobacterium tuberculosis are treated with nanocomposites derived from garlic extract at doses of 50 mg/kg and 100 mg/kg body weight. Evaluation includes the analysis of Early secreted antigenic target of 6 kDa (ESAT-6) expression and confirmation of antibodies through molecular assays. Administration of garlic and nanocomposites demonstrates significant inhibitory effects on tuberculosis progression in rats, validated by safety assessments and antibacterial efficacy. Notably, the 100 mg/kg dosage exhibits pronounced mitigation of tuberculosis-induced oxidative stress and lung damage. In conclusion, the combined administration of garlic extracts and green-synthesized nanocomposites shows promising efficacy in reducing tuberculosis infection, highlighting a potential avenue for anti-tuberculosis interventions.

Thrombocytopenia 4 (THC4): Six novel families with mutations of the cytochrome c gene.

Thrombocytopenia 4 (THC4) is an autosomal-dominant thrombocytopenia caused by mutations in CYCS, the gene encoding cytochrome c (CYCS), a small haeme protein essential for electron transport in mitochondria and cell apoptosis. THC4 is considered an extremely rare condition since only a few patients have been reported so far. These subjects presented mild thrombocytopenia and no or mild bleeding tendency. In this study, we describe six Italian families with five different heterozygous missense CYCS variants: p.Gly42Ser and p.Tyr49His previously associated with THC4, and three novel variants (p.Ala52Thr, p.Arg92Gly, and p.Leu99Val), which have been classified as pathogenic by bioinformatics and segregation analyses. Moreover, we supported functional effects of p.Ala52Thr and p.Arg92Gly on oxidative growth and respiratory activity in a yeast model. The clinical characterization of the 22 affected individuals, the largest series of THC4 patients ever reported, showed that this disorder is characterized by mild-to-moderate thrombocytopenia, normal platelet size, and function, low risk of bleeding, and no additional clinical phenotypes associated with reduced platelet count. Finally, we describe a significant correlation between the region of CYCS affected by mutations and the extent of thrombocytopenia, which could reflect different degrees of impairment of CYCS functions caused by different pathogenetic variants.

Study on the Evolution of Physicochemical Properties of Carbon Black at Different Regeneration Stages of Diesel Particulate Filters Regenerated by Non-Thermal Plasma

As a new type of aftertreatment technology, non-thermal plasma (NTP) can effectively decompose the particulate matter (PM) deposited in diesel particulate filters (DPFs). In this paper, a regeneration test of a DPF loaded with carbon black was carried out using an NTP injection system, and the changes of oxidative activity, elemental content, and occurrence state, microstructure and graphitization degree of carbon black were analyzed to reveal the evolution of the physicochemical properties of carbon black at different regeneration stages of the DPF regenerated by NTP. As the regeneration stage of the DPF advanced, Ti, Tmax, and Te of the carbon black at the bottom of the DPF decreased, which were higher than those at the regeneration interface. After the NTP reaction, the proportion of C element decreased to less than 80%, while the proportion of O element increased to more than 20%; C-O was converted to C=O and the relative content of C=O increased. The average microcrystalline length and average spacing decreased, while the average microcrystalline curvature increased. The ID1/IG (relative peak intensities) of carbon black samples decreased from 3.31 to 3.10, and the R3 (relative peak intensities, R3 = ID3/(IG + ID2 + ID3)) increased from 0.41 to 0.58. The content of carbon clusters had a great influence on the disorder of the microcrystalline structure, so the graphitization degree of carbon black decreased and the oxidation activity increased.

Enhancing catalytic activity of CuCoFe-layered double oxide towards peroxymonosulfate activation by coupling with biochar derived from durian peel for antibiotic degradation: The role of C=O in biochar and underlying mechanism of built-in electric field

CuCoFe-LDO/BCD was successfully synthesized from CuCoFe-LDH and biochar derived from durian shell (BCD). Ciprofloxacin (CFX) degraded more than 95% mainly by O2•− and 1O2 in CuCoFe-LDO/BCD(2/1)/PMS system within 10 min with a rate constant of 0.255 min−1, which was 14.35 and 2.66 times higher than those in BCD/PMS and CuCoFe-LDO/PMS systems, respectively. The catalytic system exhibited good performance over a wide pH range (3–9) and high degradation efficiency of other antibiotics. Built-in electric field (BIEF) driven by large difference in the work function/Fermi level ratio between CuCoFe-LDO and BCD accelerated continuous electron transfer from CuCoFe-LDO to BCD to result in two different microenvironments with opposite charges at the interface, which enhanced PMS adsorption and activation via different directions. As a non-radical, 1O2 was mainly generated via PMS activation by C=O in BCD. The presence of C=O in BCD resulted in an increase in atomic charge of C in C=O and redistributed the charge density of other C atoms. As a result, strong adsorption of PMS at C atom in C=O and other C with a high positive charge was favorable for 1O2 generation, whereas an enhanced adsorption of PMS at negatively charged C accounted for the generation of •OH and SO4•−. After adsorption, electrons in C of BCD became deficient and were fulfilled with those transferred from CuCoFe-LDO driven by BIEF, which ensured the high catalytic activity of CuCoFe-LDO/BCD. O2•−, on the other hand, was generated via several pathways that involved in the transformation of •OH and SO4•− originated from PMS activation by the transition of metal species in CuCoFe-LDO and negatively charged C in BCD. This study proposed a new idea of fabricating a low-cost metal-LDH and biomass-derived catalyst with a strong synergistic effect induced by BIEF for enhancing PMS activation and antibiotic degradation.

High Ammonia Nitrogen-Induced Reproductive Toxicity in Goldfish (Carassius auratus) Mature Ovary

Ammonia nitrogen is one of the major pollutants in aquaculture. However, the mechanism of ammonia stress on ovarian development and follicular atresia is unknown. In this study, goldfish (Carassius auratus) were exposed to different ammonia concentrations, including 0 (control, C) and 50 mg/L (high, H) for 48 hr at 21 ± 0.5°C. Histology of the ovarian tissue sections revealed that the high ammonia concentrations inhibited the maturation of oocytes, and induced broken and wrinkled radiation bands, follicular membranes, and the accumulation of rod-shaped yolk particles. From the transcriptome data, a total of 1,405 differentially expressed genes (DEGs) were detected between H and C groups. Most DEGs were highly enriched in low-density lipoprotein particle-mediated signaling, oxidative stress-induced premature senescence, and ovarian steroidogenesis pathway. Furthermore, a total of 19 genes were selected and determined by quantitative real-time polymerase chain reaction (qRT-PCR). The changes in oxidative stress and antioxidant activity indicated the excessive accumulation of reactive oxygen species (ROS) in ovarian tissue. The ovarian apoptosis was induced in the H group. The downregulation of genes involved in the ovarian steroidogenesis pathway indicated that ammonia nitrogen stress prevented the synthesis of sexual hormones. These results suggest that high-concentration ammonia stress induces ovarian damage in goldfish, affecting its antioxidant function, leading to excessive ROS accumulation, ovarian apoptosis, and hindered steroid synthesis, adversely affecting reproductive performance.

Effect of Acute Dietary Nitrate Supplementation on the Changes in Calf Venous Volume during Postural Change and Skeletal Muscle Pump Activity in Healthy Young Adults.

Dietary nitrate (NO3-) supplementation is known to enhance nitric oxide (NO) activity and acts as a vasodilator. In this randomized crossover study, we investigated the effect of inorganic NO3- supplementation on the changes in calf venous volume during postural change and subsequent skeletal muscle pump activity. Fifteen healthy young adults were assigned to receive beetroot juice (BRJ) or a NO3--depleted control beverage (prune juice: CON). Two hours after beverage consumption, the changes in the right calf volume during postural change from supine to upright and a subsequent right tiptoe maneuver were measured using venous occlusion plethysmography. The increase in calf volume from the supine to upright position (total venous volume [VV]) and the decrease in calf volume during the right tiptoe maneuver (venous ejection volume [Ve]) were calculated. Plasma NO3- concentration was higher in the BRJ group than in the CON group 2 h after beverage intake (p < 0.05). However, VV and Ve did not differ between CON and BRJ. These results suggest that acute intake of BRJ may enhance NO activity via the NO3- → nitrite → NO pathway but does not change calf venous pooling due to a postural change or the calf venous return due to skeletal muscle pump activity in healthy young adults.

The therapeutic role of Azadirachta indica leaves ethanolic extract against detrimental effects of Aeromonas veronii infection in Nile tilapia, Oreochromis niloticus.

Bacterial pathogens cause high fish mortalities and in turn economic losses in fish farms. Innovative strategies should be applied to control bacterial infections instead of antibiotics to avoid the resistance problem. Consequently, the present investigation studied the curative potential of Azadirachta indica leave ethanolic extract (AILEE) on Aeromonas veronii infection in Oreochromis niloticus. A preliminary trial was assessed to evaluate the curative dose of AILEE which was found to be 2.5mg/L. One hundred and sixty fish were divided into equal four groups in four replications, where group 1 and group 2 were non-challenged and treated with 0- and 2.5-mg/L AILEE, respectively. Group 3 and group 4 were challenged with A. veronii and treated with 0- and 2.5-mg/L AILEE, respectively for 10days. A. veronii infection produced severe clinical manifestations and a high mortality rate in the infected fish. Furthermore, the infected fish exhibited a significant rise in the hepatorenal indices (aspartate aminotransferase, alanine aminotransferase, and creatinine), the oxidant biomarker (malondialdehyde), and the stress indicators (glucose and cortisol). A significant reduction in the protein profile and antioxidant/immune parameters (catalase, immunoglobulin M, lysozyme, nitric oxide, and phagocytic activity) was observed in the infected fish. Water application of the infected group to 2.5-mg/L AILEE notably ameliorated the hepatorenal indices, the oxidant biomarker, and the stress indicators. Furthermore, AILEE improved the antioxidant/immune indices. Water application of 2.5-mg/L AILEE could be useful against A. veronii infection in O. niloticus culture.