The role of catalases in the prevention/promotion of oxidative stress

Shape-recoverable chitosan/sodium alginate aerogels with sustained oxygen release and antibacterial activity for diabetic wound healing

Wounds in diabetic patients are often inhibited in angiogenesis and extracellular matrix synthesis due to insufficient oxygen supply, leading to prolonged healing time. Although oxygen therapy has been shown to promote the healing of chronic wounds, its therapeutic effectiveness remains limited by high costs, complex procedures, and a lack of sustainability. In this study, we developed an aerogel composed of chitosan (CS), sodium alginate (SA), and calcium peroxide (CPO). These aerogels can absorb wound exudate and release oxygen upon contact, providing continuous oxygen delivery for over five days. The freeze-dried aerogels are soft and exhibit shape recovery properties, which facilitate enhanced oxygen transport. Furthermore, the CS/SA-CPO aerogel demonstrated strong antioxidant activity, excellent biocompatibility, and potent antibacterial properties (exceeding 99.99 %). In vivo experiments indicated that the CS/SA-CPO aerogel promotes wound healing by continuously releasing oxygen, accelerating collagen deposition, and enhancing re-epithelialization, ultimately achieving 99.65 % wound closure within 21 days. This innovative approach offers a promising strategy for managing chronic, hypoxic diabetic wounds.

Interactive toxicity effects of metronidazole, diclofenac, ibuprofen, and differently functionalized nanoplastics on marine algae Chlorella sp

Pharmaceutical products (PPs) and nanoplastics (NPs) are prominent emerging contaminants that pose serious threats to marine ecosystems. The present study aimed to investigate both pristine and combined toxicity of PPs (metronidazole, diclofenac, and ibuprofen) and polystyrene nanoplastics (PSNPs) with amine (NH2-PSNPs) and carboxyl (COOH-PSNPs) surface functionalization on marine microalgae Chlorella variabilis. Toxicity assessment included the evaluation of growth inhibition, total reactive oxygen species production, malondialdehyde content, antioxidant activity, and photosynthetic activity. Furthermore, changes in the surface functional groups of the algae after exposure to contaminants were examined. The correlation among the toxicity endpoints was assessed using Pearson correlation and cluster heatmap analysis. Zeta potential analysis and hydrodynamic size measurements revealed that the PSNPs became unstable in the presence of PPs. This instability facilitated the aggregation and rapid settlement of PSNPs, consequently impeding their direct interaction with algal cells. Growth inhibition results indicated that Chlorella variabilis exhibited minimal growth inhibition when exposed to pristine PPs (1 mg L-1), whereas PSNPs (1 mg L-1) caused substantial growth inhibition. Notably, the combined toxicity of PSNPs and PPs was lower compared to pristine PSNPs. The independent action model revealed that the combination of PPs and PSNPs showed an antagonistic mode of interaction. The potential reasons for the decreased toxicity observed in the mixture of PSNPs and PPs compared to pristine PSNPs can be attributed to diminished oxidative stress and enhanced photosynthetic activity. These findings provide valuable insights into the role of PPs in modulating the toxicity of PSNPs towards microalgae.

Dual-pathway tumor radiosensitization strategy based on engineered bacteria capable of targeted delivery of AuNPs and specific hypoxia alleviation

BACKGROUND

Radiotherapy efficacy remains constrained by two key challenges: dose-dependent toxicity to healthy tissues at high radiation doses and hypoxia-mediated tumor radioresistance. While radiosensitizers like gold nanoparticles can enhance tumor-specific radiation deposition, their targeted delivery to tumors presents a significant hurdle. Bacteria have emerged as promising bio-carriers that not only actively target tumors and penetrate complex microenvironments, but can also be genetically engineered as multifunctional platforms for radiosensitizer delivery and hypoxia alleviation.

RESULTS

An integrated nanosystem (PCM@AuNPs), composed of engineered bacteria (PCM) and gold nanoparticles (AuNPs), is used to increase the effectiveness of radiotherapy. PCM can target and colonize tumor sites more effectively, thus improving the delivery efficiency of radiosensitizers. Furthermore, PCM overexpresses catalase (CAT), which decomposes excess H2O2 into O2, helping to mitigate hypoxia in the TME. Under X-ray irradiation, PCM@AuNPs significantly enhance radiosensitization, leading to improved tumor growth inhibition while maintaining good biocompatibility.

CONCLUSIONS

An effective strategy based on an integrated nanosystem (PCM@AuNPs) for radiosensitization through multiple pathways is developed. This novel engineered bacterial strategy holds great promise for enhancing radiosensitization in cancer therapy.

Catalase-like activity of perylene diimide based radical anion: Chromogenic substrate for achieving glucose sensing

In this work, perylene diimide based radical anion (PH2-) is synthesized and characterized using optical, NOBF4 methods; cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The PH2- is stable for 120 min (2 h) in oxygenated environment and 273 min (4.5 h) in hypoxic conditions. The PH2- showed catalase-like activity to reduce H2O2 to H2O with turn-over number (TON) = 20 and turn-over frequency (TOF) = 40 h-1. The catalase-like activity can be measured using optical and electrochemical methods by monitoring the changes at 726 nm (absorbance); 585 nm (emission) and at 0.27 V. We were able to quantitatively monitor the ultra low-level concentrations of the H2O2 as low as 320 fM (absorbance) and 200 fM (emission). Moreover, PH2- could be used as a chromogenic and fluorogenic substrate for monitoring the low-level concentrations of the glucose using GOx based biochemical assay. We have demonstrated the development and validation of the glucose assay kit for the detection of glucose as low as 3.6/2.8 nM in aqueous medium and 6.2/5.6 nM in blood serum.

Genetic interaction between oxidative stress and body mass index in a Spanish population

Oxidative stress may act as a contributing factor in the development of an elevated body mass index (BMI). Oxidative stress has the potential to modulate genetic activity at various levels, including gene transcription and protein function regulation. Nevertheless, the interplay between genetic variants and oxidative stress in relation to BMI remains to be elucidated. Based on this premise, we studied the potential association between 723 single-nucleotide polymorphisms (SNPs) located within a set of 212 genes and both BMI and oxidative stress parameters in 1502 adults from the general Spanish population (Hortega Study). Oxidative stress parameters measured included malondialdehyde (MDA) levels, 8-oxo-2'-deoxyguanosine (8-oxo-dG) levels and oxidised/reduced glutathione ratio (GSSG/GSH). We also examined the potential impact of the interaction between these SNPs and oxidative stress levels on BMI. The genes selected regulate several key biological processes, including obesity, blood pressure, inflammation, lipid metabolism and redox homeostasis. Our findings indicate a robust association between specific genes and both BMI and oxidative stress parameters. Significant BMI-related interactions between genes and oxidative stress parameters were identified, which have a multifactorial impact on oxidative stress modulation and on BMI. SNPs identified in genes such as NPPA, CPT1A, DDIT3, NOX and IL6ST were significantly associated with all oxidative stress parameters analysed, indicating a substantial influence on BMI modulation. The results provide compelling evidence of a significant relationship between oxidative stress levels and genetic background. Our data provide new insights into BMI modulation by oxidative stress levels, highlighting a role for TNF as a key player in the interrelation of oxidative stress and BMI.

Stress Induced by Fishing in Common Octopus (Octopus vulgaris) and Relative Impact on Its Use as an Experimental Model

The common octopus (Octopus vulgaris), among coleoid cephalopods, has evolved the most complex nervous system and sophisticated behaviors. Historically, O. vulgaris was a key animal model for neurophysiology research, and today, it is studied for its genomic innovations. However, unlike other models, there is no octopus farming for research, so specimens must be collected from the wild. This study assessed the impact of fishing on octopuses used in research, considering those caught using artisanal pots in the 'Regno di Nettuno' Marine Protected Area, Ischia (NA). To evaluate fishing stress, we identified morphological stress indicators such as chromatophore pattern and posture, and three potential molecular markers, estrogen receptor (ER), catalase (CAT), and heat shock protein (HSP70). We measured the percentage of stress signals shown by fished specimens and analyzed their differential gene expression. The transcriptional levels of octopuses caught using traps were compared to control specimens acclimated in captivity. Results indicated fluctuations in gene expression due to fishing stress. These findings suggest that an acclimation period after the stress event of fishing is crucial for ensuring the welfare of octopuses used in research, thus enhancing the quality of physiological and ethological studies.

Association of sulfur mustard toxicity with oxidant/antioxidant system in veterans: A meta-analysis of case-control studies

Sulfur mustard (SM) is a chemical warfare agent that increases oxidative stress in veterans. The literature assessing oxidant/antioxidant parameters in SM-exposed veterans contains conflicting results. A total of 11 relevant studies were identified and screened. Data were extracted, and effect size and heterogeneity were assessed. The analysis revealed significant elevations in levels of malondialdehyde (MDA, an indicator of lipid peroxidation), catalase (CAT), and a reduction in glutathione (GSH) following SM exposure while superoxide dismutase (SOD) and total antioxidant levels did not change. The meta-analysis revealed that the MDA and CAT levels significantly increased in the two post-exposure sampling times (15-20 and 21-33 years) except for theGSH level, which decreased only in the post-exposure sampling time of 21-33 years. The subgroup meta-analysis of the type of analyzed samples indicated that SOD and CAT levels were only increased in the serum/plasma samples, while GSH was decreased. BALF/sputum and erythrocyte samples also revealed significant increases in MDA and SOD levels while GSH level was significantly decreased. This meta-analysis concluded that SM exposure affects the balance between oxidants and antioxidants, promoting oxidative stress that may persist long after exposure. This condition highlights the need for strategies to enhance antioxidant defenses in SM-exposed veterans.

Catalase-Knockout Complements the Radio-Sensitization Effect of Titanium Peroxide Nanoparticles on Pancreatic Cancer Cells

In previous studies, titanium peroxide nanoparticles (PAA-TiOx NPs) with surfaces functionalized using polyacrylic acid (PAA) and hydrogen peroxide (H2O2) demonstrated a synergistic effect when combined with X-ray irradiation. The combination generated H2O2 and reactive oxygen species (ROS) that enhanced the irradiation efficacy. In the present study, we examined the relationship between catalase and PAA-TiOx NPs sensitization to X-ray radiation because catalase is the primary antioxidant enzyme that converts H2O2 to water and oxygen. Catalase-knockout PANC-1 (dCAT) cells were generated using the CRISPR/Cas9 system, which was confirmed by the suppression of catalase expression in mRNA and protein levels that resulted in an 81.7% decrease in catalase activity compared with levels in wild-type cells. Catalase deficiency was found to increase the production of ROS, particularly in hypoxia. Also, the combination of PAA-TiOx NPs and X-ray 5 Gy resulted in a 7-fold decrease in the survival fraction (SF; p < 0.01) of dCAT cells compared with rates documented in wild-type cells. Interestingly, the combination treatment with X-ray 3 Gy in dCAT cells resulted in an SF similar to that observed in wild-type cells treated with the same combination but at a higher radiation dose (5 Gy). These results suggest that a strategy of catalase inhibition could be used to establish an advanced combination treatment of PAA-TiOx NPs and X-ray irradiation for pancreatic cancer cells.

The Toxicity of Poly(acrylonitrile-styrene-butadiene) Microplastics toward Hyalella azteca Is Associated with Biofragmentation and Oxidative Stress

Acrylonitrile-butadiene-styrene (ABS) is a thermoplastic copolymer commonly used in the electronics, automotive, and construction industries. In the aquatic environment, the formation of microplastics from larger-sized plastic waste occurs naturally, induced by physical, chemical, and biological processes that promote the aging of these particles. Here, we investigated the interactions between the freshwater amphipod Hyalella azteca and ABS microplastics (10-20 μm) (pristine and after accelerated aging) over 7 days of exposure. At the end of the exposure period, we evaluated the ability of H. azteca to fragment the ABS particles, as well as the changes in its oxidative stress biomarkers (SOD, CAT, MDA, and GST) as the result of ABS exposure. H. azteca promoted a significant fragmentation of ABS particles. The ratio of this biofragmentation was more pronounced in pristine particles. Despite the absence of significant changes in the mortality of exposed organisms, alterations in the oxidative stress biomarkers were observed. The results demonstrate the ability of H. azteca to fragment pristine and aged ABS microplastics and, the consequent susceptibility of these organisms to the effects of microplastic exposure.

Salty surprises: Developmental and behavioral responses to environmental salinity reveal higher tolerance of inland rather than coastal Bufo spinosus tadpoles

Salinization is predicted to intensify due to climate change, impacting biodiversity and ecosystem functioning. Amphibians, particularly embryos and larvae, are highly susceptible to environmental salinity. Yet, local adaptation may cause differing vulnerabilities between coastal and inland populations. In this study, we investigated the physiological, behavioural, and life-history responses to environmental salinity (0, 2 and 4 g l-1) of embryos and larvae of a widespread amphibian species (spined toad, Bufo spinosus) from salt-exposed (coastal) and salt-free (inland) populations. Moderate salinity (4 g l-1) altered embryonic and larval development in both populations, causing increased malformations, decreased body size and survival, and altered behavior, but did not affect telomere length or oxidative status. Individuals exposed to low salinity (2 g l-1) performed better across most traits. However, moderate salinity had stronger negative effects on coastal individuals, indicating a lack of local adaptation and overall lower performance compared to their inland counterparts. These findings suggest that increasing salinity will have varied impacts on organisms depending on their population origins and developmental stages.

Dimethomorph induces heart and vascular developmental defects by disrupting thyroid hormone in zebrafish embryos

Dimethomorph (DMT) is a widely-used selective active fungicide that effectively controls downy mildew, crown rot, and late blight in crops. The extensive application of DMT raises concerns about its ecological impact on non-target organisms in the environment. However, there is limited understanding of the toxicological properties of DMT on these organisms. In this study, we utilized zebrafish as an animal model to assess the toxicity of DMT induced by exposure 5.5-72 hours post-fertilization (hpf). During this period, we monitored and evaluated the development of the zebrafish heart and vascular system. Additionally, embryo samples were collected to perform molecular-level detection of PCNA, oxidative stress, and related genes. The results showed a concentration-dependent decrease in survival rate and hatching rate, shortened body length, slowed heart rate, and pericardial edema, body curvature and reduced eye size as DMT exposure concentration increased. Furthermore, DMT exposure led to impairments in the development of the heart, vascular, along with change in the expression levels of relevant genes. It also caused a decrease in cell proliferation and an increase in oxidative stress levels. Moreover, DMT disrupts the normal development of thyroid follicular cells, leading to a reduction in T3 levels. Thyroid hormone supplementation partially reverses the toxicity induced by DMT, increasing eye size, restoring body length, reducing spine curvature, and reducing pericardial edema. Therefore, we speculate that DMT likely affects the development of zebrafish embryos by disrupting normal thyroid follicle development.

Ribose-induced advanced glycation end products reduce the lifespan in Drosophila melanogaster by changing the redox state and down-regulating the Sirtuin genes

Advanced Glycation End (AGE) products are one such factor that accumulates during aging and age-related diseases. However, how exogenous AGE compounds cause aging is an area that needs to be explored. Specifically, how an organ undergoes aging and aging-related phenomena that need further investigation. The intestine is the most exposed area to food substances. How AGEs affect the intestine in terms of aging need to be explored. Drosophila melanogaster, a well-known model organism, is used to decode aging and age-associated phenomena. In this study, we fed Ribose induced Advanced Glycation End products (Rib-AGE) to D. melanogaster to study the aging mechanism. The Rib-AGE-induced aging was checked in Drosophila. We found a series of changes in Rib-AGE-fed flies. Reactive oxygen species (ROS) and nitric oxide species (NOs) were higher in the Rib-AGE-fed flies, and the antioxidant level was lower. The intestinal permeability was altered. The microorganism load was higher inside the gut. The structural arrangement of the gut's microfilament was found to be damaged, and the nuclear shape was found to be irregular. Cell death within the gut was elevated in comparison to control. The food intake was found to be reduced. The relative mRNA expression of the Sirtuin 2 and Sirtuin 6 gene of D. melanogaster was downregulated in Rib-AGE-fed flies compared to the control. All these findings strongly suggest that Rib-AGE accelerates aging and age-related disorders in D. melanogaster.

Phytotoxic response of ryegrass (Lolium multiflorum L.) to extreme exposure to two anionic surfactants

Bioremediation is an effective and environment-friendly treatment used to clean up hydrocarbon-contaminated soil. However, the effectiveness of this treatment is often limited by the low bioavailability of the target contaminants. Surfactants addition thus appears as a way to increase solubility of these hydrophobic molecules and consequently improve their bioavailability. The use of biological surfactants is often favoured over synthetic ones because they are claimed to be non-toxic to the environment though few studies have addressed this issue. The present work evaluated the effects of a synthetic surfactant, sodium dodecyl sulphate (SDS) and a biosurfactant (rhamnolipids) on germination and growth of ryegrass over a wide range of concentrations, between one up to ten times their respective critical micellar concentration (CMC). Experimental results showed that SDS inhibited seed germination of Lolium multiflorum at high concentrations (10 × CMC), unlike rhamnolipids, which did not induce any toxicity symptom at germination stage. At the growth stage, high rhamnolipid concentrations induced chronic phytotoxicity by significantly reducing root length, decreasing biomass production and disrupting the enzymatic defence system. Thus, biosurfactants are less toxic than synthetic ones but their application at high doses in bioremediation treatments might still induce phytotoxicity symptoms and thus negatively affect the environment.

Gallic acid attenuates lipopolysaccharide - induced memory deficits, neurochemical changes, and peripheral alterations in purinergic signaling

Neuroinflammation is associated with many neurological disorders. Gallic acid (GA) has attracted significant attention due to its biological properties, such as neuroprotective, anti-inflammatory, and antioxidant effects. In this study, we evaluated the effects of GA in memory, TNF-α levels, oxidative stress, and activities of acetylcholinesterase (AChE), Na+, K+-ATPase and Ca2+-ATPase in the brain of mice exposed to lipopolysaccharide (LPS). Additionally, we evaluated alterations in adenine nucleotides and nucleosides in the serum. Male mice were orally pretreated with vehicle or GA (50 or 100 mg/kg) for 14 days. Between days 8 and 14, the animals also received LPS injection (250 µg/kg) or saline. At the end of the experimental protocol, the animals were submitted to object recognition test, euthanized and cerebral cortex, hippocampus, striatum and blood were collected. LPS induced memory deficits, which were prevented by GA treatment. GA protected against LPS-induced oxidative damage in the cerebral cortex, hippocampus and striatum by reducing reactive oxygen species and nitrite levels, while increasing total thiol content and activities of antioxidant enzymes. GA also prevented LPS-induced alterations in AChE, Na+, K+-ATPase, and Ca2+-ATPase activities in brain structures. LPS elevated TNF-α levels in the hippocampus and cerebral cortex, which were attenuated by GA treatment. Furthermore, LPS caused a reduction in ADP and AMP hydrolysis and an increase in adenosine deamination in the serum, which were also prevented by GA. The effects of GA against neuroinflammation may be attributed to its potent antioxidant and anti-inflammatory properties, which modulate various pathways, including those involved in memory mechanisms.

Protective Effect of Marine Peptide from Netunea arthritica cumingii Against Gentamicin-Induced Hair Cell Damage in Zebrafish

Auditory hair cell damage induced by aminoglycoside antibiotics (AmAn) leads to hearing loss, which has a serious effect on people's mental and physical health. This ototoxicity is thought to be related with the excessive accumulation of reactive oxygen species (ROS) in hair cells. However, therapeutic agents that protect hair cells are limited. Marine peptides have been shown to have excellent potential applications in disease prevention and treatment. Therefore, this study investigated the protective effects of an active peptide from Neptunea arthritica cumingii against AmAn-induced hair cell damage using the model of hair cell damage zebrafish. We identified the number, ultrastructure, and function of hair cells using fluorescence probes and scanning electron microscopy. The uptake of AmAn, ROS level, mitochondrial permeability transition pore, and apoptosis in hair cells were also tested by fluorescence labeling and TUNEL assay. The molecular mechanism for hair cell protection exerted by the peptide was detected by a real-time quantitative PCR assay. The results indicated that the peptide suppressed the uptake of AmAn but did not damage the function of hair cells mediating hearing. It also prevented ROS accumulation, decreased the occurrence of apoptosis, and rescued the abnormal opening and expressions of mitochondrial permeability transition pore and genes related to antioxidants. The peptide may be an effective therapeutic agent for AmAn-induced ototoxicity. In the future, we plan to use mammalian models to further investigate the otoprotective effect of the peptide.

Catalase-associated immune responses in plant-microbe interactions: A review

Catalase, an enzyme central to maintaining redox balance and combating oxidative stress in plants, has emerged as a key player in plant defense mechanisms and interactions with microbes. This review article provides a comprehensive analysis of catalase-associated immune responses in plant-microbe interactions. It underscores the importance of catalase in plant defense mechanisms, highlights its influence on plant susceptibility to pathogens, and discusses its implications for understanding plant immunity and host-microbe dynamics. This review contributes to the growing body of knowledge on catalase-mediated immune responses and offers insights that can aid in the development of strategies for improved plant health and disease resistance.

The Metallothionein System in Tetrahymena thermophila Is Iron-Inducible

Metallothioneins are multifunctional proteins implicated in various cellular processes. They have been used as biomarkers of heavy metal exposure and contamination due to their intrinsic ability to bind heavy metals and their transcriptional response to both physiological and noxious metal ions such as cadmium (Cd) and mercury (Hg). In this study, we aimed to clarify the role of iron and reactive oxygen species (ROSs) in the induction of the metallothionein system (Mtt) in the ciliate protozoan Tetrahymena thermophila. We investigated the relative mRNA abundances of the metallothionein genes Mtt1, Mtt2/4, and Mtt5, revealing for the first time their responsiveness to iron exposure. Furthermore, by using inhibitors of superoxide dismutase (SOD) and catalase (CAT), alone or in combination with iron, we highlighted the roles of superoxide ion and endogenous hydrogen peroxide, as well as the complex interplay between the metal and ROSs. These results enhance our understanding of the metallothionein system in ciliates and suggest that ROSs may be a primary evolutionary driver for the selection of these proteins in nature.

The effect of early administration of antibiotics or feeding a diet containing coccidiostats on the level of their accumulation in liver and the redox status of turkeys

Early administration of antibiotics may worsen the functioning of the turkeys' antioxidant system. It was also assumed that the longer the time of administration of an antibiotic, e.g. a coccidiostat, the greater the risk of its accumulation in the liver. The study aimed to determine whether early administration of antibiotics or feeding a diet containing coccidiostats causes accumulation in the liver and whether it affects the deterioration of the antioxidant system, and whether preventive vaccinations can intensify it. A total of 3 080 female turkeys were randomly allocated to eight groups. The experiment had a two-factorial design, with four treatments (C, M, E, D) and two groups of birds (vaccinated +, unvaccinated -). The C group did not receive the coccidiostat or antibiotics. Group M was administered monensin at 90 mg/kg feed for 56 days of life. Group E received enrofloxacin at 10 mg/kg BW, and group D received doxycycline at 50 mg/kg BW, added to drinking water, for the first 5 days of life. One-day-old turkeys from groups C+, M+, E+, and D+ were administered live-attenuated vaccines against turkey rhinotracheitis and Newcastle disease by coarse spray; 28-day-old birds were administered a subcutaneously injected inactivated vaccine against Ornithobacterium rhinotracheale. Turkeys from groups C-, M-, E-, and D- were not vaccinated. It was determined that as a result of administration of enrofloxacin or doxycycline until the 5th day of life, biotransformation of these antibiotics occurred in the liver until the 56th day of life of the turkeys, which was confirmed by their lower level than the Maximum Residue Level. Because the concentration of monensin in the liver of turkeys gradually increased with the extension of the time of its administration in the diet, it is probable that discontinuing its addition a day before the slaughter of birds will result in the presence of this coccidiostat in the liver of turkeys. Despite the accumulation of monensin in the liver of turkeys, this coccidiostat did not increase oxidative reactions in the organism of turkeys. Vaccination of turkeys can reduce oxidative reactions and apoptosis in the body. However, the effect of the redox system reaction is different immediately after vaccination, which is due to the mechanism of action of the immune system. If it is necessary to administer an antibiotic in the early rearing period, the effects of doxycycline on the organism's immunity including antioxidant defence will be less severe than those of enrofloxacin.

Enhanced antioxidant phytochemicals and catalase activity of celery by-products by a combined strategy of selenium and PGPB under restricted N supply

Introduction

The reduction of N supplied combined with the use of biostimulants can be an efficient strategy that allows sustainable agriculture to achieve better economic, nutritional and environmental goals without reducing production. Moreover, the industrial processing of celery generates large amounts of waste. Therefore the purpose of this study was improve crop management strategies to reduce nitrate pollution while turning crop waste into value-added products for others sectors.

Methods

Consequently, in this work twelve treatments were examined: three N nitrogen content in the nutrient solution (100% control, 60%, and 30%) combined with the inoculation of the roots with Azotobacter salinestris, and foliar application selenium solution (8 μM, Na2SeO4). The celery parts from plants grown under limited N dose showed a higher antioxidant activity and TPC (total phenolic compounds) content.

Results and discussion

The antioxidant activity increased 28% in leaves and 41% in by-products and TPC improved 27% in leaves and 191% in by-products respect to the control. Besides, a significant reduction of β-carotene content (56%, 11% and 43% in petioles, leaves and by-products respect to the control, respectively) was obtained in plants fed with restricted dose of N. The catalase activity was not affected by N dose. The inoculation of the plants with Azotobacter, together with a reduced N dose, achieved a greater accumulation of all the parameters studied. This accumulation was maximum when Se was applied to the leaves compared with the control and depending on the celery part: TPC (121-450%); antioxidant activity (60-68%), of catalase activity (59% - 158%), and of pigments content (50-90%). These findings can boost the valorization of celery by-products as excellent source of bioactive compounds.

Quercus infectoria Gall Ethanolic Extract Accelerates Wound Healing through Attenuating Inflammation and Oxidative Injuries in Skin Fibroblasts

Quercus infectoria Olivier (Fagaceae) nutgall, a traditional Asian medicine, is renowned for its efficacy in treating wounds and skin disorders. Although the gall extract has shown promising results in accelerating wound healing in diabetic animal models, its mechanisms, particularly the effects on redox balance, remain poorly understood. This study aims to investigate the effects and mechanisms of Q. infectoria gall ethanolic extract (QIG) on wound healing in fibroblasts, with a specific emphasis on its modulation of oxidative stress. Hydrogen peroxide (H2O2)-treated L929 cells were used as an in vitro model of oxidation-damaged fibroblasts. QIG exhibited potent antioxidant activity with 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and ferric reducing antioxidant power (FRAP) assay values of 305.43 ± 7.48, 508.94 ± 15.12, and 442.08 ± 9.41 µM Trolox equivalents (TE)/µg, respectively. Elevated H2O2 levels significantly reduced L929 cell viability, with a 50% lethal concentration of 1.03 mM. QIG mitigated H2O2-induced cytotoxicity in a dose-dependent manner, showing protective effects in pre-, post-, and co-treatment scenarios. QIG significantly reduced H2O2-induced intracellular reactive oxygen species production and inflammation-related gene expression (p < 0.05). Additionally, at 25 µg/mL, QIG remarkably improved wound closure in H2O2-treated L929 cells by approximately 9.4 times compared with the H2O2 treatment alone (p < 0.05). These findings suggest QIG has potential therapeutic applications in wound healing, mediated through the regulation of oxidative stress and inflammatory response.

Single and mixture exposure to atrazine and ciprofloxacin on Clarias gariepinus antioxidant defense status, hepatic condition and immune response

Atrazine (ATRA) and ciprofloxacin (CPRO) are widely detected, persistent and co-existing aquatic pollutants. This study investigated effects of 14-day single and joint ATRA and CPRO exposure on juvenile Clarias gariepinus. Standard bioassay methods were used to determine responses of oxidative stress, hepatic condition, and immunological biomarkers on days 7 and 14. Seven groups were used: Control, CPROEC, CPROSubl, ATRAEC, ATRASubl, CPROEC+ATRAEC, and CPROSubl+ATRASubl. The test substances caused decreased activity of superoxide dismutase, catalase, and glutathione peroxidase. Lipid peroxidation was elevated, especially in CPRO-ATRA mixtures. Serum aminotransferases (ALT, and AST), and alkaline phosphatase activity increased significantly. Total protein, albumin, total immunoglobulin, and respiratory burst decreased significantly. Therefore, single and joint exposure to CPRO and ATRA poses adverse consequences on aquatic life.

Changes in Lipid Metabolites and Enzyme Activities of Wheat Flour during Maturation

The maturation of wheat flour is a transformative process that elevates its processing and culinary attributes to their peak performance levels. Despite extensive research on starch and gluten protein modifications, the impact of lipid changes has been largely unexplored. This study addresses this gap by examining the maturation of freshly milled wheat flour at 15 °C, 25 °C, and 40 °C over 60 days, focusing on enzymatic activities-lipase, lipoxidase, and catalase-and lipid metabolites, including free fatty acids, conjugated trienes, p-anisidine value, and total oxidation value. The results of this study showed that free fatty acids continued to increase at all temperatures, with the most significant increase of 50% at 15 °C. The p-anisidine value followed a pattern of initial increase followed by a decline, while conjugated trienes were markedly higher at 40 °C, suggesting temperature's significant influence on lipid peroxidation. Notably, total oxidation values became erratic post 30 days, indicating a shift in oxidative dynamics. This study underscores the correlation between lipid metabolites and enzymatic activities, revealing the enzymes' pivotal role in lipid oxidation. The interplay of temperature and time offers valuable insights for optimizing wheat flour maturation, ensuring superior quality for various applications.

Is Cadmium Genotoxicity Due to the Induction of Redox Stress and Inflammation? A Systematic Review

The transition metal cadmium (Cd) is toxic to humans and can induce cellular redox stress and inflammation. Cd is a recognized carcinogen, but the molecular mechanisms associated with its genotoxicity and carcinogenicity are not defined. Therefore, a systematic review was undertaken to examine the scientific literature that has covered the molecular mechanism of Cd genotoxicity and its relationship to cellular redox stress and inflammation. An electronic database search of PubMed, Scopus, and the Web of Science Core Collection was conducted to retrieve the studies that had investigated if Cd genotoxicity was directly linked to the induction of redox stress and inflammation. Studies included exposure to Cd via in vitro and in vivo routes of administration. Of 214 publications retrieved, 10 met the inclusion criteria for this review. Preclinical studies indicate that Cd exposure causes the induction of reactive oxygen species (ROS) and, via concomitant activity of the transcription factor NF-κβ, induces the production of pro-inflammatory cytokines and a cytokine profile consistent with the induction of an allergic response. There is limited information regarding the impact of Cd on cellular signal transduction pathways, and the relationship of this to genotoxicity is still inconclusive. Nevertheless, pre-incubation with the antioxidants, N-acetylcysteine or sulforaphane, or the necroptosis inhibitor, necrostatin-1, reduces Cd toxicity; indicative that these agents may be a beneficial treatment adjunct in cases of Cd poisoning. Collectively, this review highlights that Cd-induced toxicity and associated tissue pathology, and ultimately the carcinogenic potential of Cd, may be driven by redox stress and inflammatory mechanisms.

Research progress in mechanism of anticancer action of shikonin targeting reactive oxygen species

Excessive buildup of highly reactive molecules can occur due to the generation and dysregulation of reactive oxygen species (ROS) and their associated signaling pathways. ROS have a dual function in cancer development, either leading to DNA mutations that promote the growth and dissemination of cancer cells, or triggering the death of cancer cells. Cancer cells strategically balance their fate by modulating ROS levels, activating pro-cancer signaling pathways, and suppressing antioxidant defenses. Consequently, targeting ROS has emerged as a promising strategy in cancer therapy. Shikonin and its derivatives, along with related drug carriers, can impact several signaling pathways by targeting components involved with oxidative stress to induce processes such as apoptosis, necroptosis, cell cycle arrest, autophagy, as well as modulation of ferroptosis. Moreover, they can increase the responsiveness of drug-resistant cells to chemotherapy drugs, based on the specific characteristics of ROS, as well as the kind and stage of cancer. This research explores the pro-cancer and anti-cancer impacts of ROS, summarize the mechanisms and research achievements of shikonin-targeted ROS in anti-cancer effects and provide suggestions for designing further anti-tumor experiments and undertaking further experimental and practical research.

Advances in metal-organic framework-based nanozymes in ROS scavenging medicine

Reactive oxygen species (ROS) play important roles in regulating various physiological functions in the human body, however, excessive ROS can cause serious damage to the human body, considering the various limitations of natural enzymes as scavengers of ROS in the body, the development of better materials for the scavenging of ROS is of great significance to the biomedical field, and nanozymes, as a kind of nanomaterials which can show the activity of natural enzymes. Have a good potential for the development in the area of ROS scavenging. Metal-organic frameworks (MOFs), which are porous crystalline materials with a periodic network structure composed of metal nodes and organic ligands, have been developed with a variety of active nanozymes including catalase-like, superoxide dismutase-like, and glutathione peroxidase-like enzymes due to the adjustability of active sites, structural diversity, excellent biocompatibility, and they have shown a wide range of applications and prospects. In the present review, we first introduce three representative natural enzymes for ROS scavenging in the human body, methods for the detection of relevant enzyme-like activities and mechanisms of enzyme-like clearance are discussed, meanwhile, we systematically summarize the progress of the research on MOF-based nanozymes, including the design strategy, mechanism of action, and medical application, etc. Finally, the current challenges of MOF-based nanozymes are summarized, and the future development direction is anticipated. We hope that this review can contribute to the research of MOF-based nanozymes in the medical field related to the scavenging of ROS.

Dietary Effects of Fermented Cottonseed Meal Substituting Fishmeal on the Growth, Biochemical Indexes, Antioxidant Capacity, and Muscle Quality of Juvenile Golden Pompano (Trachinotus ovatus)

This study investigated the effects of the dietary replacing fishmeal (FM) with fermented cottonseed meal (FCSM) on growth performance, body coloration, serum biochemistry, muscle quality, and liver antioxidant capacity of juvenile golden pompano (Trachinotus ovatus). Fish were fed with five experimental diets (0 (FM), 12.5% (CSM12.5), 25% (CSM25), 50% (CSM50), and 100% (CSM100) replacement levels) for 8 weeks. The weight gain rate (WGR), specific growth rate (SGR), and condition factor (CF) in fish fed with CSM25 were significantly higher than those of the FM (P < 0.05). ALT, GLU, TG, TC, and LDL of fish fed with CSM100 diet were significantly higher than those in FM (P < 0.05). No significant difference was observed in SOD, CAT, and MDA among all treatments (P > 0.05). The relative gene expression of Nrf2 of fish fed with CSM25 diet was higher than that of the other groups (P < 0.05). The relative gene expression of Keap-1 of fish fed with CSM25 diet was lower than those in FM (P < 0.05). In addition, the replacement of a high proportion of FM with FCSM negatively affect the liver antioxidant capacity of fish. With dietary replacement of FM with FCSM increasing 0%-25%, the relative expressions of GH, myf5, and MSTN were significantly upregulated (P > 0.05). Based on these results, we recommend that of FCSM in the diet of golden pompano, whereas the optimal level of FCSM should be carefully evaluated. In conclusion, the optimum level of dietary replacing FM with FCSM in T. ovatus diet was 24.74%-29.38% based on SGR and WGR.

Exploring In Vivo Pulmonary and Splenic Toxicity Profiles of Silicon Quantum Dots in Mice

Silicon-based quantum dots (SiQDs) represent a special class of nanoparticles due to their low toxicity and easily modifiable surface properties. For this reason, they are used in applications such as bioimaging, fluorescent labeling, drug delivery, protein detection techniques, and tissue engineering despite a serious lack of information on possible in vivo effects. The present study aimed to characterize and evaluate the in vivo toxicity of SiQDs obtained by laser ablation in the lung and spleen of mice. The particles were administered in three different doses (1, 10, and 100 mg QDs/kg of body weight) by intravenous injection into the caudal vein of Swiss mice. After 1, 6, 24, and 72 h, the animals were euthanized, and the lung and spleen tissues were harvested for the evaluation of antioxidant enzyme activity, lipid peroxidation, protein expression, and epigenetic and morphological changes. The obtained results highlighted a low toxicity in pulmonary and splenic tissues for concentrations up to 10 mg SiQDs/kg body, demonstrated by biochemical and histopathological analysis. Therefore, our study brings new experimental evidence on the biocompatibility of this type of QD, suggesting the possibility of expanding research on the biomedical applications of SiQDs.

Recent Progress in Anti-Tumor Nanodrugs Based on Tumor Microenvironment Redox Regulation

The growth state of tumor cells is strictly affected by the specific abnormal redox status of the tumor microenvironment (TME). Moreover, redox reactions at the biological level are also central and fundamental to essential energy metabolism reactions in tumors. Accordingly, anti-tumor nanodrugs targeting the disruption of this abnormal redox homeostasis have become one of the hot spots in the field of nanodrugs research due to the effectiveness of TME modulation and anti-tumor efficiency mediated by redox interference. This review discusses the latest research results of nanodrugs in anti-tumor therapy, which regulate the levels of oxidants or reductants in TME through a variety of therapeutic strategies, ultimately breaking the original "stable" redox state of the TME and promoting tumor cell death. With the gradual deepening of study on the redox state of TME and the vigorous development of nanomaterials, it is expected that more anti-tumor nano drugs based on tumor redox microenvironment regulation will be designed and even applied clinically.

Systemic and local effect of oxidative stress on recurrent aphthous stomatitis: systematic review

Recurrent aphthous stomatitis (RAS) is a chronic and recurrent inflammatory disease of the mouth. It is characterised by the appearance of painful ulcers in the oral mucosa. RAS is believed to be a multifactorial disease with genetic predisposition, environmental factors and alterations in the immune system. Oxidative stress, caused by an imbalance between free radicals and the antioxidant system, also appears to be involved in the pathogenesis of RAS. Several risk factors, such as smoking, iron and vitamin deficiency and anxiety, may contribute to the development of the disease. Understanding the underlying mechanisms may help in the prevention and treatment of RAS. We searched PubMed, Scopus and Web of Science databases for articles on oxidative stress in patients with RAS from 2000 to 2023. Studies analysing oxidant and antioxidant levels in the blood and saliva of RAS patients and healthy controls were selected. Of 170 potentially eligible articles, 24 met the inclusion criteria: 11 studies on blood samples, 6 on salivary samples and 7 on both blood and salivary samples. Multiple oxidative and antioxidant markers were assessed in blood and saliva samples. Overall, statistically significant differences were found between RAS patients and healthy controls for most markers. In addition, increased oxidative DNA damage was observed in patients with RAS. Patients with RAS show elevated levels of oxidative stress compared to healthy controls, with a significant increase in oxidative markers and a significant decrease in antioxidant defences in saliva and blood samples.

Precision nutrition to reset virus-induced human metabolic reprogramming and dysregulation (HMRD) in long-COVID

SARS-CoV-2, the etiological agent of COVID-19, is devoid of any metabolic capacity; therefore, it is critical for the viral pathogen to hijack host cellular metabolic machinery for its replication and propagation. This single-stranded RNA virus with a 29.9 kb genome encodes 14 open reading frames (ORFs) and initiates a plethora of virus-host protein-protein interactions in the human body. These extensive viral protein interactions with host-specific cellular targets could trigger severe human metabolic reprogramming/dysregulation (HMRD), a rewiring of sugar-, amino acid-, lipid-, and nucleotide-metabolism(s), as well as altered or impaired bioenergetics, immune dysfunction, and redox imbalance in the body. In the infectious process, the viral pathogen hijacks two major human receptors, angiotensin-converting enzyme (ACE)-2 and/or neuropilin (NRP)-1, for initial adhesion to cell surface; then utilizes two major host proteases, TMPRSS2 and/or furin, to gain cellular entry; and finally employs an endosomal enzyme, cathepsin L (CTSL) for fusogenic release of its viral genome. The virus-induced HMRD results in 5 possible infectious outcomes: asymptomatic, mild, moderate, severe to fatal episodes; while the symptomatic acute COVID-19 condition could manifest into 3 clinical phases: (i) hypoxia and hypoxemia (Warburg effect), (ii) hyperferritinemia ('cytokine storm'), and (iii) thrombocytosis (coagulopathy). The mean incubation period for COVID-19 onset was estimated to be 5.1 days, and most cases develop symptoms after 14 days. The mean viral clearance times were 24, 30, and 39 days for acute, severe, and ICU-admitted COVID-19 patients, respectively. However, about 25-70% of virus-free COVID-19 survivors continue to sustain virus-induced HMRD and exhibit a wide range of symptoms that are persistent, exacerbated, or new 'onset' clinical incidents, collectively termed as post-acute sequelae of COVID-19 (PASC) or long COVID. PASC patients experience several debilitating clinical condition(s) with >200 different and overlapping symptoms that may last for weeks to months. Chronic PASC is a cumulative outcome of at least 10 different HMRD-related pathophysiological mechanisms involving both virus-derived virulence factors and a multitude of innate host responses. Based on HMRD and virus-free clinical impairments of different human organs/systems, PASC patients can be categorized into 4 different clusters or sub-phenotypes: sub-phenotype-1 (33.8%) with cardiac and renal manifestations; sub-phenotype-2 (32.8%) with respiratory, sleep and anxiety disorders; sub-phenotype-3 (23.4%) with skeleto-muscular and nervous disorders; and sub-phenotype-4 (10.1%) with digestive and pulmonary dysfunctions. This narrative review elucidates the effects of viral hijack on host cellular machinery during SARS-CoV-2 infection, ensuing detrimental effect(s) of virus-induced HMRD on human metabolism, consequential symptomatic clinical implications, and damage to multiple organ systems; as well as chronic pathophysiological sequelae in virus-free PASC patients. We have also provided a few evidence-based, human randomized controlled trial (RCT)-tested, precision nutrients to reset HMRD for health recovery of PASC patients.

TRIM21 Promotes Oxidative Stress and Ferroptosis through the SQSTM1-NRF2-KEAP1 Axis to Increase the Titers of H5N1 Highly Pathogenic Avian Influenza Virus

Tripartite motif-containing protein 21 (TRIM21) is involved in signal transduction and antiviral responses through the ubiquitination of protein targets. TRIM21 was reported to be related to the imbalance of host cell homeostasis caused by viral infection. Our studies indicated that H5N1 highly pathogenic avian influenza virus (HPAIV) infection up-regulated TRIM21 expression in A549 cells. Western blot and qPCR results showed that knockdown of TRIM21 alleviated oxidative stress and ferroptosis induced by H5N1 HPAIV and promoted the activation of antioxidant pathways. Co-IP results showed that TRIM21 promoted oxidative stress and ferroptosis by regulating the SQSTM1-NRF2-KEAP1 axis by increasing SQSTM1 K63-linked polyubiquitination under the condition of HPAIV infection. In addition, TRIM21 attenuated the inhibitory effect of antioxidant NAC on HPAIV titers and enhanced the promoting effect of ferroptosis agonist Erastin on HPAIV titers. Our findings provide new insight into the role of TRIM21 in oxidative stress and ferroptosis induced by viral infection.

Biofragmentation of Polystyrene Microplastics: A Silent Process Performed by Chironomus sancticaroli Larvae

Polystyrene (PS) is one of the main synthetic polymers produced around the world, and it is present in the composition of a wide variety of single-use objects. When released into the environment, these materials are degraded by environmental factors, resulting in microplastics. We investigated the ability of Chironomus sancticaroli (Diptera, Chironomidae) to promote the fragmentation of PS microspheres (24.5 ± 2.9 μm) and the toxic effects associated with exposure to this polymer. C. sancticaroli larvae were exposed to 3 different concentrations of PS (67.5, 135, and 270 particles g-1 of dry sediment) for 144 h. Significant lethality was observed only at the highest concentration. A significant reduction in PS particle size as well as evidence of deterioration on the surface of the spheres, such as grooves and cracks, was observed. In addition, changes in oxidative stress biomarkers (SOD, CAT, MDA, and GST) were also observed. This is the first study to report the ability of Chironomus sp. to promote the biofragmentation of microplastics. The information obtained demonstrates that the macroinvertebrate community can play a key role in the degradation of plastic particles present in the sediment of freshwater environments and can also be threatened by such particle pollution.

Current trends in targeting the oxidative stress in glaucoma (Review)

Glaucoma is a progressive optic neuropathy characterised by retinal ganglion cell degeneration and visual field loss. Glaucoma is considered to be the leading cause of blindness in the industrialised countries. Oxidative damage is an important pathogenic factor in glaucoma, which triggers trabecular meshwork (TM) degeneration, which then leads to intraocular hypertension. Neurodegenerative insults during glaucomatous neurodegeneration initiate an immune response to restore tissue homeostasis. However, the oxidative stress (OS) that develops during the pathogenic processes of glaucoma, along with the agerelated OS, plays a critical role in shifting the physiological equilibrium. In the TM from glaucoma donors, proinflammatory markers were found, which were induced by the activation of a stress response. Chronic changes in the composition of antioxidants found in aqueous humour may induce alterations in TM as well as in the optic nerve head cells. Highlighting the pathogenic role of reactive oxygen species (ROS) in glaucoma has implications in preventing this disease. Various clinical trials are available to test the efficacy of antioxidant drugs in glaucoma management. In this review, we discuss the OS as a therapeutic target, suggesting that the modulation of a pro-oxidant/antioxidant status might be a relevant target for glaucoma prevention and therapy.

Climate warming has divergent physiological impacts on sympatric lizards

Climate warming is expected to affect the vulnerability of sympatric species differentially due to their divergent traits, but the underlying physiological mechanisms of those impacts are poorly understood. We conducted field warming experiments (present climate vs. warm climate) using open-top chambers to determine the effects of climate warming on active body temperature, oxidative damage, immune competence, growth and survival in two sympatric desert-dwelling lizards, Eremias multiocellata and Eremias argus from May 2019 to September 2020. Our climate warming treatment did not affect survival of the two species, but it did increase active body temperatures and growth rate in E. multiocellata compared to E. argus. Climate warming also induced greater oxidative damage (higher malondialdehyde content and catalase activity) in E. multiocellata, but not in E. argus. Further, climate warming increased immune competence in E. multiocellata, but decreased immune competence in E. argus, with regards to white blood cell counts, bacteria killing ability and relative expression of immunoglobulin M. Our results suggest that climate warming enhances body temperature, and thereby oxidative stress, immune competence and growth in E. multiocellata, but decreases immune competence of E. argus, perhaps as a cost of thermoregulation to maintain body temperatures under climate warming. The divergent physiological effects of climate warming on sympatric species may have profound ecological consequences if it eventually leads to changes in reproductive activities, population dynamics and community structure. Our study highlights the importance of considering interspecific differences in physiological traits when we evaluate the impact of climate warming on organisms, even for those closely-related species coexisting within the same geographical area.

Combined effects of green tea supplementation and eccentric exercise on nuclear factor erythroid 2-related factor 2 activity

PURPOSE

This study investigated whether combining eccentric exercise and green tea supplementation synergistically increased nuclear factor erythroid 2-related factor 2 (NRF2) activity, a transcription factor responsible for coordinating endogenous antioxidant expression.

METHODS

In a double-blinded, randomized, between-subjects design, 24 males (mean [SD]; 23 [3] years, 179.6 [6.1] cm, 78.8 [10.6] kg) performed 100 drop jumps following a 6 days supplementation period with either green tea (poly)phenols (n = 12; 500 mg·d-1) or a placebo (n = 12; inulin). NRF2/antioxidant response element (ARE) binding in peripheral blood mononuclear cells (PBMCs), catalase (CAT) and glutathione reductase (GR) activity, 8-hydroxy-2'-deoxyguanosine (8-OHdG) excretion, and differential leukocyte counts were measured pre-, post-, 1 h and 24 h post-exercise.

RESULTS

Exercise did not increase NRF2/ARE binding (p = 0.12) (fold change vs rest: green tea = [post] 0.78 ± 0.45, [1 h] 1.17 ± 0.54, [24 h] 1.06 ± 0.56; placebo = [post] 1.40 ± 1.50, [1 h] 2.98 ± 3.70, [24 h] 1.04 ± 0.45). Furthermore, CAT activity (p = 0.12) and 8-OHdG excretion (p = 0.42) were unchanged in response to exercise and were not augmented by green tea supplementation (p > 0.05 for all). Exercise increased GR activity by 30% (p = 0.01), however no differences were found between supplement groups (p = 0.51). Leukocyte and neutrophil concentrations were only elevated post-exercise (p < 0.001 for all).

CONCLUSION

Eccentric exercise, either performed alone or in conjunction with green tea supplementation, did not significantly increase NRF2 activity in PBMCs.

TRIAL REGISTRATION NUMBER

osf.io/kz37g (registered: 15/09/21).

Evaluation of the protective effect of coenzyme Q10 on hepatotoxicity caused by acute phosphine poisoning

Background: Aluminum phosphide (AlP) poisoning is prevalent in numerous countries, resulting in high mortality rates. Phosphine gas, the primary agent responsible for AlP poisoning, exerts detrimental effects on various organs, notably the heart, liver and kidneys. Numerous studies have documented the advantageous impact of Coenzyme Q10 (CoQ10) in mitigating hepatic injuries. The objective of this investigation is to explore the potential protective efficacy of CoQ10 against hepatic toxicity arising from AlP poisoning. Method: The study encompassed distinct groups receiving almond oil, normal saline, exclusive CoQ10 (at a dosage of 100 mg/kg), AlP at 12 mg/kg; LD50 (lethal dose for 50%), and four groups subjected to AlP along with CoQ10 administration (post-AlP gavage). CoQ10 was administered at 10, 50, and 100 mg/kg doses via Intraparietal (ip) injections. After 24 h, liver tissue specimens were scrutinized for mitochondrial complex activities, oxidative stress parameters, and apoptosis as well as biomarkers such as aspartate transaminase (AST) and alanine transaminase (ALT). Results: AlP induced a significant decrease in the activity of mitochondrial complexes I and IV, as well as a reduction in catalase activity, Ferric Reducing Antioxidant Power (FRAP), and Thiol levels. Additionally, AlP significantly elevated oxidative stress levels, indicated by elevated reactive oxygen species (ROS) production, and resulted in the increment of hepatic biomarkers such as AST and ALT. Administration of CoQ10 led to a substantial improvement in the aforementioned biochemical markers. Furthermore, phosphine exposure resulted in a significant reduction in viable hepatocytes and an increase in apoptosis. Co-treatment with CoQ10 exhibited a dose-dependent reversal of these observed alterations. Conclusion: CoQ10 preserved mitochondrial function, consequently mitigating oxidative damage. This preventive action impeded the progression of heart cells toward apoptosis.

Free radicals and oxidative stress: Mechanisms and therapeutic targets

BACKGROUND

Free radicals are small extremely reactive species that have unpaired electrons. Free radicals include subgroups of reactive species, which are all a product of regular cellular metabolism. Oxidative stress happens when the free radicals production exceeds the capacity of the antioxidant system in the body's cells.

OBJECTIVE

The current review clarifies the prospective role of antioxidants in the inhibition and healing of diseases.

METHODS

Information on oxidative stress, free radicals, reactive oxidant species, and natural and synthetic antioxidants was obtained by searching electronic databases like PubMed, Web of Science, and Science Direct, with articles published between 1987 and 2023 being included in this review.

RESULTS

Free radicals exhibit a dual role in living systems. They are toxic byproducts of aerobic metabolism that lead to oxidative injury and tissue disorders and act as signals to activate appropriate stress responses. Endogenous and exogenous sources of reactive oxygen species are discussed in this review. Oxidative stress is a component of numerous diseases, including diabetes mellitus, atherosclerosis, cardiovascular disease, Alzheimer's disease, Parkinson's disease, and cancer. Although various small molecules assessed as antioxidants have shown therapeutic prospects in preclinical studies, clinical trial outcomes have been inadequate. Understanding the mechanisms through which antioxidants act, where, and when they are active may reveal a rational approach that leads to more tremendous pharmacological success. This review studies the associations between oxidative stress, redox signaling, and disease, the mechanisms through which oxidative stress can donate to pathology, the antioxidant defenses, the limits of their effectiveness, and antioxidant defenses that can be increased through physiological signaling, dietary constituents, and probable pharmaceutical interference. Prospective clinical applications of enzyme mimics and current progress in metal- and non-metal-based materials with enzyme-like activities and protection against chronic diseases have been discussed.

CONCLUSION

This review discussed oxidative stress as one of the main causes of illnesses, as well as antioxidant systems and their defense mechanisms that can be useful in inhibiting these diseases. Thus, the positive and deleterious effects of antioxidant molecules used to lessen oxidative stress in numerous human diseases are discussed. The optimal level of vitamins and minerals is the amount that achieves the best feed benefit, best growth rate, and health, including immune efficiency, and provides sufficient amounts to the body.

Oxidative Stress and Antioxidant Defense Mechanisms in Acute Ischemic Stroke Patients with Concurrent COVID-19 Infection

Stroke remains a debilitating cerebrovascular condition associated with oxidative stress, while COVID-19 has emerged as a global health crisis with multifaceted systemic implications. This study investigates the hypothesis that patients experiencing acute ischemic stroke alongside COVID-19 exhibit elevated oxidative stress markers and altered antioxidant defense mechanisms compared to those with acute ischemic stroke. We conducted a single-center prospective cross-sectional study to investigate oxidative stress balance through oxidative damage markers: TBARS (thiobarbituric acid reactive substances level) and PCARB (protein carbonyls); antioxidant defense mechanisms: TAC (total antioxidant capacity), GPx (glutathione peroxidase), GSH (reduced glutathione), CAT (catalase), and SOD (superoxide dismutase); as well as inflammatory response markers: NLR (neutrophil-to-lymphocyte ratio), CRP (C-reactive protein), and ESR (erythrocyte sedimentation rate). Statistical analyses and correlation models were employed to elucidate potential associations and predictive factors. Our results revealed increased oxidative stress, predominantly indicated by elevated levels of TBARS in individuals experiencing ischemic stroke alongside a concurrent COVID-19 infection (p < 0.0001). The Stroke-COVID group displayed notably elevated levels of GSH (p = 0.0139 *), GPx (p < 0.0001 ****), SOD (p = 0.0363 *), and CAT (p = 0.0237 *) activities. Multivariate analysis found a significant association for TBARS (p < 0.0001 ****), PCARB (p = 0.0259 *), and GPx activity (p < 0.0001 ****), together with NLR (p = 0.0220 *) and CRP (p = 0.0008 ***). Notably, the interplay between stroke and COVID-19 infection appears to amplify oxidative damage, potentially contributing to exacerbated neurological deficits and poorer outcomes. This study highlights the intricate relationship between oxidative stress, inflammation, and concurrent health conditions. Understanding these interactions may open avenues for novel therapeutic strategies aimed at ameliorating oxidative damage in patients with acute ischemic stroke and COVID-19, ultimately improving their prognosis and quality of life.

Proteomic analysis reveals changes in the proteome of human THP-1 macrophages infected with Paracoccidioides brasiliensis

Paracoccidioides spp. is the etiologic agent of Paracoccidioidomycosis (PCM), a systemic disease with wide distribution in Latin America. Macrophages are very important cells during the response to infection by P. brasiliensis. In this study, we performed a proteomic analysis to evaluate the consequences of P. brasiliensis yeast cells on the human THP-1 macrophage proteome. We have identified 443 and 2247 upregulated or downregulated proteins, respectively, in macrophages co-cultured with yeast cells of P. brasiliensis in comparison to control macrophages unexposed to the fungus. Proteomic analysis revealed that interaction with P. brasiliensis caused metabolic changes in macrophages that drastically affected energy production pathways. In addition, these macrophages presented regulated many factors related to epigenetic modifications and gene transcription as well as a decrease of many proteins associated to the immune system activity. This is the first human macrophage proteome derived from interactions with P. brasiliensis, which contributes to elucidating the changes that occur during the host response to this fungus. Furthermore, it highlights proteins that may be targets for the development of new therapeutic approaches to PCM.

Black soldier fly pulp in the diet of golden pompano: Effect on growth performance, liver antioxidant and intestinal health

Black soldier fly (Hermetia illucens) has been widely researched as a protein source for fish meal replacement in aquaculture, but few studies have focused on its potential as a feed additive for growth and immune enhancement. We conducted a 56-day culture experiment to determine the impact of feed addition of black soldier fly pulp (BSFP, with 86.2% small peptides in dry basis) on growth performance, plasma biochemistry, liver antioxidant levels, intestinal immunity, digestion and microbiota of juvenile golden pompano (Trachinotus ovatus, 5.63 ± 0.02 g). BSFP was added to the basal diet at 0%, 1%, 3%, 5%, 7% and 9% (named Control, BSFP-1, BSFP-3, BSFP-5, BSFP-7, BSFP-9), respectively. BSFP increased the weight gain rate, specific growth rate, protein efficiency ratio and reduced the feed conversion rate of juvenile T. ovatus, the optimal growth performance was reached at BSFP-1, after which a negative feedback phenomenon was observed. Low levels of BSFP upregulated the expression of hepatic antioxidant, intestinal tight junctions, anti-inflammatory related genes and enhanced antioxidant, immune and intestinal digestive enzyme activities, which simultaneously reduced hepatic malondialdehyde and plasma aspartate transaminase and alanine aminotransferase concentrations. However, at BSFP-7, catalase activity was significantly reduced, while NF-κB p65 and pro-inflammatory cytokines transcription was significantly enhanced (P < 0.05). The results suggest that high doses of BSFP addition may damage fish health by inhibiting small peptide uptake, decreasing the activity of antioxidant enzyme and activating the canonical NF-κB pathway. Conversely, low doses of BSFP enhanced intestinal tight junction protein transcription, digestive enzyme activity and immune performance, inhibited pathogenic microbiota, while enhancing liver antioxidant capacity, which was associated with activated Nrf2-Keap1 pathway and suppressed NF-κB pathway, showing its potential as a feed additive to aquafeeds.

Polyphenols Cause Structure Dependent Effects on the Metabolic Profile of Human Hepatocarcinogenic Cells

SCOPE

Although many beneficial health effects are attributed to polyphenols their influence on the human metabolome has not been elucidated yet. The ubiquitous occurrence of polyphenols in the human diet demands comprehensive knowledge about physiological and toxicological effects of these compounds on human cells.

METHODS AND RESULTS

The human hepatocarcinogenic cell line HepG2 is used to elucidate the effects of 13 polyphenols and three respective phenolic degradation products on the human metabolome using HPLC-MS/MS. To investigate structure-activity-relationships, structurally related examples of polyphenols from different compound classes are selected. The analysis of catechins points toward a relation between the degree of hydroxylation and the extent of metabolic effects particularly on the urea cycle and the pentose phosphate pathway (PPP). A correlation between the modulation of the PPP and the stability of the compounds is demonstrated, which may be caused by reactive oxygen species (ROS). The incubation of flavones and alkenylbenzenes demonstrates reduced activity of methoxylated compounds and no impact of the B-ring position.

CONCLUSION

In general, polyphenols induce a multitude of metabolic effects, for example, on energy metabolism, PPP, and urea cycle. These metabolic alterations may be related to the widely reported bioactivity of these compounds such as the anticarcinogenic effects.

Bacillus velezensis BVE7 as a promising agent for biocontrol of soybean root rot caused by Fusarium oxysporum

Introduction

Soybean root rot (SRR), caused by Fusarium oxysporum, is a severe soil-borne disease in soybean production worldwide, which adversely impacts the yield and quality of soybean. The most effective method for managing crop soil-borne diseases and decreasing reliance on chemical fungicides, such as Bacillus spp., is via microbial biocontrol agents.

Methods and Results

In this study, a soil-isolated strain BVE7 was identified as B. velezensis, exhibiting broad-spectrum activity against various pathogens causing soybean root rot. BVE7 sterile filtrate, at a concentration of 10%, demonstrated significant antifungal activity by inhibiting the conidial germination, production, and mycelial growth of F. oxysporum by 61.11%, 73.44%, and 85.42%, respectively, causing hyphal malformations. The antifungal compound produced by BVE7 demonstrated adaptability to a standard environment. The pot experiment showed that BVE7 suspension could effectively control soybean root rot, with the highest control efficiency of 75.13%. Furthermore, it considerably enhanced the activity of catalase, phenylalanine ammonia lyase, superoxide dismutase, and peroxidase in soybean roots, while also preventing an increase in malondialdehyde activity. By improving the host resistance towards pathogens, the damage caused by fungi and the severity of soybean root rot have been reduced.

Discussion

This study presents the innovative utilization of B. velezensis, isolated from soybean roots in cold conditions, for effectively controlling soybean root rot caused by F. oxysporum. The findings highlight the remarkable regional and adaptive characteristics of this strain, making it an excellent candidate for combating soybean root rot in diverse environments. In conclusion, B. velezensis BVE7 demonstrated potential in effectively reducing SRR incidence and can be considered as a viable option for SRR management.

New Dawn for Atherosclerosis: Vascular Endothelial Cell Senescence and Death

Endothelial cells (ECs) form the inner linings of blood vessels, and are directly exposed to endogenous hazard signals and metabolites in the circulatory system. The senescence and death of ECs are not only adverse outcomes, but also causal contributors to endothelial dysfunction, an early risk marker of atherosclerosis. The pathophysiological process of EC senescence involves both structural and functional changes and has been linked to various factors, including oxidative stress, dysregulated cell cycle, hyperuricemia, vascular inflammation, and aberrant metabolite sensing and signaling. Multiple forms of EC death have been documented in atherosclerosis, including autophagic cell death, apoptosis, pyroptosis, NETosis, necroptosis, and ferroptosis. Despite this, the molecular mechanisms underlying EC senescence or death in atherogenesis are not fully understood. To provide a comprehensive update on the subject, this review examines the historic and latest findings on the molecular mechanisms and functional alterations associated with EC senescence and death in different stages of atherosclerosis.

Role of Caveolin-1 on the molybdenum and cadmium exposure induces pulmonary ferroptosis and fibrosis in the sheep

Molybdenum (Mo) is an essential trace element that exists in all tissues of the human body, but excessive Mo intake has a toxic effect. Cadmium (Cd) is a widely known and harmful heavy metal that exists in the environment. Although studies on Mo and Cd are available, it is still unknown how the combination of Mo and Cd causes pulmonary injury. Forty-eight sheep that were 2 months old were chosen and randomly separated into four groups as follows: Control group, Mo group, Cd group, and Mo + Cd group. The experiment lasted 50 days. The results showed that Mo and/or Cd caused significant pathological damage and oxidative stress in the lungs of sheep. Moreover, Mo and/or Cd exposure could downregulate the expression levels of xCT (SLC7A11 and SLC3A2), GPX4 and FTH-1 and upregulate the expression levels of PTGS2 and NCOA4, which led to iron overload and ferroptosis. Ferroptosis induced Wnt/β-catenin-mediated fibrosis by elevating the expression levels of Caveolin-1 (CAV-1), Wnt 1, Wnt3a, β-catenin (CTNNB1), TCF4, Cyclin D1, mmp7, α-SMA (ACTA2), Collagen 1 (COL1A1) and Vimentin. These changes were particularly noticeable in the Mo and Cd combination group. In conclusion, these data demonstrated that Mo and/or Cd exposure led to lung ferroptosis by inhibiting the SLC7A11/GSH/GPX4 axis, which in turn increases CAV-1 expression and subsequently activates the Wnt/β-catenin pathway, leading to fibrosis in sheep lungs.

A combined transcriptomic and physiological approach to understanding the adaptive mechanisms to cope with oxidative stress in Fusarium graminearum

In plant-pathogen interactions, oxidative bursts are crucial for plants to defend themselves against pathogen infections. Rapid production and accumulation of reactive oxygen species kill pathogens directly and cause local cell death, preventing pathogens from spreading to adjacent cells. Meanwhile, the pathogens have developed several mechanisms to tolerate oxidative stress and successfully colonize plant tissues. In this study, we investigated the mechanisms responsible for resistance to oxidative stress by analyzing the transcriptomes of six oxidative stress-sensitive strains of the plant pathogenic fungus Fusarium graminearum. Weighted gene co-expression network analysis identified several pathways related to oxidative stress responses, including the DNA repair system, autophagy, and ubiquitin-mediated proteolysis. We also identified hub genes with high intramodular connectivity in key modules and generated deletion or conditional suppression mutants. Phenotypic characterization of those mutants showed that the deletion of FgHGG4, FgHGG10, and FgHGG13 caused sensitivity to oxidative stress, and further investigation on those genes revealed that transcriptional elongation and DNA damage responses play roles in oxidative stress response and pathogenicity. The suppression of FgHGL7 also led to hypersensitivity to oxidative stress, and we demonstrated that FgHGL7 plays a crucial role in heme biosynthesis and is essential for peroxidase activity. This study increases the understanding of the adaptive mechanisms to cope with oxidative stress in plant pathogenic fungi. IMPORTANCE Fungal pathogens have evolved various mechanisms to overcome host-derived stresses for successful infection. Oxidative stress is a representative defense system induced by the host plant, and fungi have complex response systems to cope with it. Fusarium graminearum is one of the devastating plant pathogenic fungi, and understanding its pathosystem is crucial for disease control. In this study, we investigated adaptive mechanisms for coping with oxidative stress at the transcriptome level using oxidative stress-sensitive strains. In addition, by introducing genetic modification technique such as CRISPR-Cas9 and the conditional gene expression system, we identified pathways/genes required for resistance to oxidative stress and also for virulence. Overall, this study advances the understanding of the oxidative stress response and related mechanisms in plant pathogenic fungi.

Oxidative post-translational modification of catalase confers salt stress acclimatization by regulating H2O2 homeostasis in Malus hupehensis

Reactive oxygen species (ROS) play an essential role as both signaling molecule and damage agent during salt stress. As a signaling molecule, proper accumulation of H2O2 is crucial to trigger stress response and enhance stress tolerance. However, the dynamic regulation mechanism of H2O2 remains unclear. Here, we show that MhCAT2 (catalase 2 in Malus hupehensis) undergoes oxidative modification in an O2•--dependent manner and that oxidation at His225 residue reduces the MhCAT2 activity. Furthermore, the substitution of His225 with Tyr weakens the activity of MhCAT2. The oxidation modification provides a post-translational brake mechanism for the excessive scavenging of H2O2 caused by salt stress-induced catalase (CAT) over-expression. Overall, this finding provides mechanistic insights on stress tolerance augmentation by an O2•--mediated switch that regulates H2O2 homeostasis in Malus hupehensis.

Potential virulence factors of Nocardia seriolae AHLQ20-01 based on whole-genome analysis and its pathogenicity to largemouth bass (Micropterus salmoides)

Nocardia seriolae is a major causative agent of fish nocardiosis that results in serious economic losses in the aquaculture industry. However, the virulence factors and pathogenic mechanisms of the bacterium are poorly understood. Here, a new N. seriolae strain AHLQ20-01 was isolated from the diseased Micropterus salmoides and identified by phenotypic examination combined with 16S rRNA sequencing. Subsequently, the potential virulence factors of the strain were analysed at genome level by whole-genome sequencing. The results showed that the whole-genome sequence derived from N. seriolae AHLQ20-01 circular chromosome contains 8,129,380 bp DNA with G + C content of 68.14%, and encompasses 7650 protein-coding genes, 114 pseudo-genes, 3 rRNAs, 66 tRNAs and 36 non-coding RNAs. More importantly, a total of 139 genes, which mainly involved in adhesion, invasion, resistance to oxidative and nitrosative stress, phagosome arresting, iron acquisition system, toxin production and bacterial secretion systems, were identified as core virulence-associated genes. Furthermore, the pathogenicity of N. seriolae AHLQ20-01 to M. salmoides was further investigated through experimental infection. It was found that the LD₅₀ value of the strain to M. salmoides was 9.3 × 10⁶  colony forming unit/fish. Histopathological examination demonstrated typical granuloma with varying sizes in the liver, head kidney, spleen and heart of the experimentally infected fish. Terminal deoxynucleotidyl transferase dUTP nick end labelling assay and 4',6-diamidino-2-phenylindole staining showed that there were distinctly more apoptotic cells in all the tested tissues in the infection group, but not in the control group. Together, these findings provide the foundation to further explore the pathogenic mechanism of N. seriolae, which might contribute to the prevention and treatment of fish nocardiosis.

A Novel Drug Delivery System: Hyodeoxycholic Acid-Modified Metformin Liposomes for Type 2 Diabetes Treatment

Metformin is a first-line drug for the clinical treatment of type 2 diabetes; however, it always leads to gastrointestinal tolerance, low bioavailability, short half-life, etc. Liposome acts as an excellent delivery system that could reduce drug side effects and promote bioavailability. Hyodeoxycholic acid, a cholesterol-like structure, can regulate glucose homeostasis and reduce the blood glucose levels. As an anti-diabetic active ingredient, hyodeoxycholic acid modifies liposomes to make it overcome the disadvantages of metformin as well as enhance the hypoglycemic effect. By adapting the thin-film dispersion method, three types of liposomes with different proportions of hyodeoxycholic acid and metformin were prepared (HDCA:ME-(0.5:1)-Lips, HDCA:ME-(1:1)-Lips, and HDCA:ME-(2:1)-Lips). Further, the liposomes were characterized, and the anti-type 2 diabetes activity of liposomes was evaluated. The results from this study indicated that three types of liposomes exhibited different characteristics—Excessive hyodeoxycholic acid decreased encapsulation efficiency and drug loading. In the in vivo experiments, liposomes could reduce the fasting blood glucose levels, improve glucose tolerance, regulate oxidative stress markers and protect liver tissue in type 2 diabetic mice. These results indicated that HDCA:ME-(1:1)-Lips was the most effective among the three types of liposomes prepared and showed better effects than metformin. Hyodeoxycholic acid can enhance the hypoglycemic effect of metformin and play a suitable role as an excipient in the liposome.