Antioxidant Enzyme Activities Research Articles

LkERF6 enhances drought and salt tolerance in transgenic tobacco by regulating ROS homeostasis

The transcription factor Ethylene Responsive Factor (ERF) is crucial for responding to various environmental stressors. Proteins containing the ERF-associated amphiphilic repression (EAR) motif often inhibit gene expression. However, the functions of LkERF, an EAR motif-containing protein from Larix kaempferi, especially in reactive oxygen species (ROS) homeostasis, are not well understood. In the present research, we introduce a novel transcription factor, LkERF6, which contains an EAR motif and positively regulates gene expression, thereby enhancing drought and salt tolerance in tobacco. LkERF6 is classified within the ERF-B1 subfamily due to its conserved AP2/ERF domain and EAR motif. Subcellular localization assays demonstrated LkERF6 is primarily localized in the nucleus. Further analysis revealed that LkERF6 interacts with GCC and DRE elements and is significantly induced by NaCl and PEG6000. Moreover, LkERF6 transgenic tobacco plants exhibit lower ROS accumulation and higher levels of antioxidant enzyme activities. Additionally, correlation analysis identified a strong association between LkERF6 and three genes: LkSOD, LkCCS, and LkCAT. Y1H, EMAS, and DLR assays confirmed that LkERF6 directly interacts with the promoters of these genes through GCC-box and DRE-box to activate their expression. These findings shed new light on the function of EAR motif-containing transcription factors and highlight LkERF6’s crucial role in enhancing abiotic stress resistance by activating multiple ROS clearance genes.

Oxidative stress levels and antioxidant defense mechanisms (Nrf2-Keap1 signaling pathway) in the Harderian glands of hibernating Daurian ground squirrels

Cyclic hibernation bouts in Daurian ground squirrels (Spermophilus dauricus) lead to repeated suppression and recovery of mitochondrial respiratory function across multiple organs, potentially impacting reactive oxygen species (ROS) dynamics. The Harderian gland (HG) plays an important role in endocrine regulation through porphyrin secretion. However, the influence of hibernation on oxidative pressure and associated antioxidant pathways in the HG remains inadequately understood. In the current study, we investigated the morphological changes, secretory activity, ROS levels, and underlying mechanisms in the HG of Daurian ground squirrels at distinct circannual stages of hibernation. Results indicated that: (1) Protoporphyrin levels in the HG increased during hibernation compared to the summer active (SA) phase, with a reduction in acinar lumen during torpor, potentially related to hibernation in a low-light environment. (2) Hydrogen peroxide (H2O2) and malondialdehyde (MDA) content during hibernation and post-hibernation (POST) did not exceed the levels observed in SA, indicating that the HG effectively mitigated oxidative pressure and lipid peroxidation during these periods. (3) Superoxide dismutase (SOD) activity increased while glutathione peroxidase (GPx) activity decreased during IBA compared to both SA and torpor, although total antioxidant capacity (T-AOC) remained stable across all stages. (4) Overall fluorescent intensity of nuclear factor erythroid 2-related factor 2 (Nrf2) and Kelch-like ECH-associated protein 1 (Keap1) was significantly lower than in SA. These findings demonstrate that the HG in Daurian ground squirrels maintains a favorable oxidative status through the regulation of antioxidant enzyme activities during hibernation and even post-hibernation.

Schistosomicidal Effects of Moringa oleifera Seed Oil Extract on Schistosoma mansoni-Infected Mice.

Schistosomiasis causes severe hepatic fibrosis, making it a global health issue. Moringa oleifera seed oil extract, which had antiparasitic, anti-inflammatory and antioxidant effects, was investigated as an alternative treatment. The 50 mice were divided into control, infected, praziquantel-treated, M. oleifera seed oil extract-treated and combined treatment groups. These treatments were examined for their effects on egg granulomas, hepatic enzymes, total protein, albumin, antioxidant enzymes and pro-inflammatory cytokines. M. oleifera seed oil and/or PZQ significantly reduced egg numbers, granuloma size and liver histopathology. M. oleifera seed oil reduced hepatic enzyme activity, increased total protein and albumin, and increased antioxidant enzyme activity while decreasing malondialdehyde. M. oleifera seed oil reduced the levels of pro-inflammatory cytokines. M. oleifera seed oil may treat schistosomiasis instead of PZQ due to its antifibrotic, immunomodulatory and schistosomicidal properties.

Evaluating the therapeutic effect of different forms of silymarin on liver status and expression of some genes involved in fat metabolism, antioxidants and anti-inflammatory in older laying hens.

Silymarin, the predominant compound of milk thistle, is an extract took out from milk thistle (Silybum marianum) seeds, containing a mixture of flavonolignans with strong antioxidant capability. The experiment was conducted using 70 Lohmann LSL-Lite hens at 80 weeks of age with 7 treatments each with 10 replicates. Treatments included: (1) control diet without silymarin, (2) daily intake of 100mg silymarin powder/kg body weight (BW) (PSM100), (3) daily intake of 200mg silymarin powder/kg BW (PSM200), (4) daily intake of 100mg nano-silymarin/kg BW (NSM100), (5) daily intake of 200mg nano-silymarin/kg BW (NSM200), (6) daily intake of 100mg lecithinized silymarin/kg BW (LSM100) and (7) daily intake of 200mg lecithinized silymarin/kg BW (LSM200). The birds were housed individually, and diets were fed for 12 weeks. Scanning electron microscopy showed that NSM was produced with the average particle size of 20.30nm. Silymarin treatment improved serum antioxidant enzyme activity. All groups receiving silymarin showed a decrease in liver malondialdehyde content, expression of fatty acid synthase, tumour necrosis factor alpha, interleukin 6 (IL-6) genes in the liver, and hepatic steatosis than the control, except those fed the PSM100 diet. There were decreases in liver dry matter and fat contents, non-alcoholic fatty liver disease and hepatocyte ballooning, and an increase in glutathione peroxidase gene expression and a decrease in iNOS gene expression in birds fed the NSM100, NSM200, LSM100 and LSM200 diets compared to the control group. Moreover, all groups receiving silymarin showed a significant decrease in liver weight compare to the control group. Overall, the effects of silymarin when converted to NSM or LSM and offered at the level of 200mg/kg BW were more pronounced on the hepatic variables and may be useful in the prevention of the liver disease in older laying hens.

Eukaryotic expression of chitinase from dark sleeper (Odontobutis potamophila) and its effects on growth and immunity

Chitinase, an enzyme that hydrolyzes β-1,4-glycosidic bonds to degrade chitin, is essential for the digestion of chitin in fish. In this study, the chitinase OpCht from Odontobutis potamophila was expressed in Pichia pastoris, and its enzymatic properties and functional effects were evaluated. The findings revealed that OpCht exhibited optimal activity at pH 6.0 and 50 °C, with stability in the pH range of 4–8 and temperatures from 4 to 40 °C. K+, Na+, Ca2+, Mg2+, Mn2+, Hg2+, and Al3+ showed varying degrees of activation on the enzyme. At the end of the 8-week trial, the addition of OpCht significantly increased the height of intestinal villi and the thickness of the muscular layer, leading to significantly weight in the treated groups. The alleviation of intestinal inflammation also resulted in an increased survival rate (SR) of O. potamophila. High concentration treatment groups (2, 4 μg/g) showed significantly elevated digestive enzyme activities, as well as increased antioxidant enzyme activities and immune parameters. These results demonstrate that the P. pastoris expression system has successfully produced the chitinase OpCht from O. potamophila, and the addition of a certain concentration of OpCht can promote fish growth and enhance immune functions, offering a promising enzyme preparation for the aquaculture industry.

Citric acid-driven cadmium uptake and growth promotion mechanisms in Brassica napus

Citric acid (CA) is well-known for mitigating cadmium (Cd) toxicity in plants. Yet, the underlying mechanisms driving growth promotion, Cd detoxification/tolerance, and enhanced phytoremediation processes remain incompletely understood. This study investigated the effects of CA application (2.5 mM) on Brassica napus grown in Cd-contaminated (30 mg kg−1) growth medium through a controlled pot experiment. Cd exposure alone significantly impaired various plant physiological parameters in B. napus. Whereas CA application significantly (p < 0.05) enhanced physiological attributes, Cd detoxification and tolerance by modulating key genes involved in photosynthesis and Cd transport, including the metal-transporting P1B-type ATPases (Cd/zinc heavy metal-transporting ATPase 1; HMA1) and light-harvesting chlorophyll a/b-binding 3 (LHCB3). Notably, CA application increased Cd accumulation in stems and leaves by 4% and 35%, respectively, enhancing bioconcentration factors (BCF) by 12% in stems and 40% in leaves while reducing root BCF by 10%. This translocation was facilitated by the upregulation of HMA4, HMA2, and plant Cd resistance (PCR2) genes in plant leaves, improving Cd mobility within the plant. Furthermore, CA induced a 34% increase in phytochelatins and a 32% upregulation in metallothioneins, accompanied by a significant reduction in oxidative stress markers, including a 40% decrease in hydrogen peroxide and a 44% decline in malondialdehyde levels in leaves. Enhanced antioxidant enzyme activity and osmolyte accumulation further contributed to improved Cd detoxification/sequestration in leaves, reduced oxidative stress, and improved photosynthetic efficiency, resulting in enhanced plant biomass production and Cd tolerance. Transcriptomic analysis showed that CA treatment substantially influenced the expression of 12,291 differentially expressed genes (DEGs), with 750 common genes consistently downregulated in CK vs Cd treatment group but upregulated in Cd vs Cd-CA treatment group. Additionally, CA modulated 11 DEGs associated with 32 gene ontologies in the citrate pathway under Cd stress, highlighting its targeted regulatory effect on metabolic pathways involved in Cd stress response. This study offers novel insights into the synergistic role of CA in promoting plant growth and regulating Cd uptake in B. napus, highlighting its potential to enhance phytoremediation strategies.

Assessing antioxidant responses in C6 and U-87 MG cell lines exposed to high copper levels

Copper excess has been tested as an anticancer therapy, due to its properties to generate oxidative stress resulting in tumoral cell death. Thus, this study aimed to evaluate the impact of copper excess on oxidative stress and antioxidant responses in glioma cells, establishing the antioxidant system as a target of copper toxicity in tumoral cells. C6 and U-87 MG cells were exposed to CuSO4 (0–600 μM) for 24-48 h. SOD, CAT, GPx, GR, and CK activities, protein and non-protein thiol levels (PSH and NPSH), and O2− production were assessed, alongside SOD1, GPx1, and GR gene expression. Results revealed a decrease in GPx, GR, and CAT activity after CuSO4 exposure in both cell lines over 24-48 h, while SOD activity initially increased, then declined after 48 h. CK activity was also decreased in C6 cells. NPSH and PSH levels dropped after 24 h, and O2− production was observed in all CuSO4 concentrations. GR mRNA was reduced in both cell lines, contrasting with increased GPx1 mRNA in C6. U-87 MG cells exhibited higher levels of SOD1 mRNA, while C6 cells displayed lower expression. Our findings suggest that copper excess limits antioxidant enzyme activity and thiol levels, particularly in the C6 cells, likely attributable to oxidative stress or direct copper-enzyme interactions. Moreover, our results imply differences in copper toxicity regarding the cell lineage used, highlighting the importance of analyzing high copper levels effects in different models. Moreover, it could be proposed that the antioxidant system is a target of copper toxicity, contributing to glioma cell death.

Folic Acid - Based Hydrogels Co-assembled with Protocatechuic Acid for Enhanced Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) presents a significant therapeutic challenge due to the need for oral drug delivery systems that withstand acidic environment of stomach while effectively targeting intestinal inflammation. To address this issue, we created a novel hydrogel system based on a folic acid (FA)-dopamine (DA) conjugate, co-assembled with protocatechuic acid (PCA), to form F-DP hydrogels. These hydrogels demonstrated robust anti-gastric acid, mucosal adhesive, and injectable properties, enhancing their efficacy for targeted delivery. In DSS-induced colitis mouse models, treatment with F-DP hydrogels resulted in significant therapeutic improvements, including increased body weight, reduced disease activity index (DAI), and maintained colon length. Biochemical assays revealed that F-DP hydrogels significantly enhanced antioxidant enzyme activities (GSH and SOD) and reduced oxidative stress markers (NO and MDA). Histological assessments confirmed effective repair of the colonic mucosal barrier, restoration of tight junction protein ZO-1, and reduction of inflammatory lesions. Furthermore, immunofluorescence staining indicated that F-DP hydrogels facilitated macrophages polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, thereby reducing inflammation and promoting tissue repair. Our study demonstrates that F-DP hydrogels show significant potential for improving IBD treatment through enhanced gastric resistance, intestinal adhesion, and synergistic anti-inflammatory effects, warranting further investigation for clinical applications.

Tenofovir alafenamide compared to tenofovir disoproxil fumarate, induces dysglycemia, and dyslipidemia in Wistar rats.

To determine the metabolic effects of tenofovir alafenamide (TAF) compared to tenofovir disoproxil fumarate (TDF) in vivo . Male Wistar rats ( Rattus novergicus , 250-300 g body weight) were divided into three groups ( n = 8) and orally treated daily with 1.0 ml distilled water (group 1), TAF (0.42 mg/kg) (group 2), or TDF (5.0 mg/kg) (group 3), respectively, for 56 days. Glucose tolerance tests were done before the animals were sacrificed by halothane overdose, and blood was collected by cardiac puncture for the analysis of plasma lipids, electrolytes, and insulin. The kidney and pancreatic tissues were excised and homogenized to measure oxidative stress. Compartmentation of TAF and TDF was determined in NRK-52 and peripheral blood mononuclear cells (PBMCs). There were no significant differences in weight gain among controls, TAF- or TDF-treated rats. TAF-treated rats had significantly increased fasting blood glucose (FBG), fasting plasma insulin (FPI), insulin resistance, impaired glucose tolerance, and dyslipidemia compared to control or TDF-treated rats, respectively. There was increased lipid peroxidation in the pancreas of TAF-treated compared to TDF-treated or control animals, respectively. TDF- treated rats presented with symptoms of Fanconi syndrome compared to TAF-treated or control animals, respectively. Kidney homogenates from TDF-treated animals had significantly reduced antioxidant enzyme activity compared to TAF-treated animals or controls, respectively. Intracellular concentrations of TAF were significantly higher than TDF in both NRK-52E cells and PBMC, respectively. TAF treatment is weight-neutral and causes dysglycemia, and dyslipidemia but not Fanconi syndrome compared to TDF.

Application of hydrogen-rich water maintains red pitaya fruit quality through regulation of ROS and energy metabolism

Hydrogen-rich water (HRW) treatment has been shown to enhance the shelf life of fruit and vegetables. This study aimed to investigate the effects of HRW on improving the quality of red pitaya and its underlying regulatory mechanisms. The results revealed that applying HRW at a 70% concentration reduced decay and weight loss rates, slowed the respiratory rate, and delayed the decline in titratable acidity and total soluble solids. Additionally, HRW treatment mitigated the increase in superoxide anion production and hydrogen peroxide levels, while enhancing antioxidant enzyme activities and gene expression, including those of peroxidase, superoxide dismutase, glutathione peroxidase, catalase, ascorbate peroxidase, monodehydroascorbate reductase, and glutathione reductase. Non-enzymatic antioxidant compounds such as ascorbate and glutathione also increased. Moreover, RT-qPCR analysis showed that HRW treatment upregulated HcMYB6 and downregulated HcR2R3MYB. Dual-luciferase reporter assays indicated that HcMYB6 activated the expression of HcSOD and HcCAT, whereas HcR2R3MYB repressed their expression. These findings suggest that HcMYB6 and HcR2R3MYB may be involved in reactive oxygen species metabolism, with HcMYB6 being induced and HcR2R3MYB inhibited by HRW treatment. Furthermore, HRW treatment led to increased adenosine triphosphate and adenosine diphosphate levels, a decrease in adenosine monophosphate content, and elevated gene expression and activity of Ca2⁺-ATPase, succinate hydrogenase, H⁺-ATPase, and cytochrome C. Collectively, these results demonstrate that HRW treatment effectively reduces oxidative damage and improves energy status, thereby preserving the quality of red pitaya fruit.

Prestorage hot water treatments retard papaya fruit deterioration and enhanced fruit quality in cold storage

Papaya (Carica papaya) fruit has a short shelf life and suffers significant postharvest losses due to climacteric, instant ripening and perishable nature. Pre-storage hot water treatment (HWT) has significant potential to delay decay incidence in horticultural commodities. The present study was designed to evaluate effectiveness of HWT on &amp;lsquo;Red lady&amp;rsquo; papaya fruit for minimizing the fruit decay and maintaining the quality during storage. Physiologically mature unripe &amp;lsquo;Red lady&amp;rsquo; papaya fruit harvested from a commercial papaya orchard. Selected fruits were treated at three different hot water temperatures (50 &amp;deg;C, 52 &amp;deg;C and 54 &amp;deg;C) along with a control (room temp) for 10 minutes thereafter stored at 12 &amp;deg;C and 85&amp;ndash;90% RH for four weeks. Different sensory evaluation, fruit quality scales and enzymatic activities were observed at weekly intervals. Fruit stored after 54 &amp;deg;C HWT showed lower weight loss (4.63%), decay incidence (5.1%) and higher fruit firmness (12.92 N) relative to control. Fruit treated at 52 &amp;deg;C HWT improved the fruit acidity, but total soluble solids decreased than control. The results revealed that ascorbic acid (33.33 mg/100 g), total phenolic contents (35 mg/g FW) total antioxidants (47.50% DPPH inhibition), and antioxidative enzyme activities were improved by 52 &amp;deg;C HWT. It is concluded that pre storage papaya fruit treatment (HWT @ 52 &amp;deg;C) preserves the quality of fruit throughout storage on the other hand at 54 &amp;deg;C HWT helps in decreased fruit decaying. It can be summarized that papaya fruit can be treated with hot water in the range of 52&amp;ndash;54 &amp;deg;C to support the fruit shelf life and suppress fruit decay along with maintaining fruit quality. Practical applications: Papaya (Carica papaya L.) is a climacteric fruit which is highly susceptible to fungal attacks after harvest. Due to its perishable nature, it becomes decayed and huge amount of highly nutritious and medicinally important fruit is wasted. Recently people are more concerned about food safety which limits the use of fungicides for controlling the fruit decay in papaya. However, heat treatment has tremendous potential to control microbial decay, and keep food commodities safe from hazardous chemicals. In this study, the hot water treatment has successfully suppressed the fruit decay and maintained fruit quality of papaya in the course of entire period of cold storage. These findings indicated that use of hot water treatment is a practical approach for increasing the shelf life of papaya fruit.

Honey Enriched with Additives Alleviates Behavioral, Oxidative Stress, and Brain Alterations Induced by Heavy Metals and Imidacloprid in Zebrafish.

Environmental concerns have consistently been a focal point for the scientific community. Pollution is a critical ecological issue that poses significant threats to human health and agricultural production. Contamination with heavy metals and pesticides is a considerable concern, a threat to the environment, and warrants special attention. In this study, we investigated the significant issues arising from sub-chronic exposure to imidacloprid (IMI), mercury (Hg), and cadmium (Cd), either alone or in combination, using zebrafish (Danio rerio) as an animal model. Additionally, we assessed the potential protective effects of polyfloral honey enriched with natural ingredients, also called honey formulation (HF), against the combined sub-chronic toxic effects of the three contaminants. The effects of IMI (0.5 mg·L-1), Hg (15 μg·L-1), and Cd (5 μg·L-1), both individually and in combination with HF (500 mg·L-1), on zebrafish were evaluated by quantifying acetylcholinesterase (AChE) activity, lipid peroxidation (MDA), various antioxidant enzyme activities like superoxide dismutase and glutathione peroxidase (SOD and GPx), 2D locomotor activity, social behavior, histological and immunohistochemical factors, and changes in body element concentrations. Our findings revealed that all concentrations of pollutants may disrupt social behavior, diminish swimming performances (measured by total distance traveled, inactivity, and swimming speed), and elevate oxidative stress (OS) biomarkers of SOD, GPx, and MDA in zebrafish over the 21-day administration period. Fish exposed to IMI and Hg + Cd + IMI displayed severe lesions and increased GFAP (Glial fibrillary acidic protein) and S100B (S100 calcium-binding protein B) protein expression in the optic tectum and cerebellum, conclusively indicating astrocyte activation and neurotoxic effects. Furthermore, PCNA (Proliferating cell nuclear antigen) staining revealed reduced cell proliferation in the IMI-exposed group, contrasting with intensified proliferation in the Hg + Cd group. The nervous system exhibited significant damage across all studied concentrations, confirming the observed behavioral changes. Moreover, HF supplementation significantly mitigated the toxicity induced by contaminants and reduced OS. Therefore, the exposure to chemical mixtures offers a more complete picture of adverse impacts on aquatic ecosystems and the supplementation with bioactive compounds can help to reduce the toxicity induced by exposure to environmental pollutants.

Cardioprotective effects of cinnamoyl imidazole on apoptosis and oxidative stress in hypoxia/reoxygenation-induced H9C2 cell lines

BackgroundThis study explored the effects of cinnamoyl imidazole on alleviating oxidative stress and apoptosis in hypoxia/reoxygenation (H/R)-induced H9C2 cells, using computational analysis with in-vitro validation. MethodsComputational techniques, including SwissADME and Swiss Target Prediction, were employed to predict the ADME properties and to identify targets of cinnamoyl imidazole. Differential gene expression (DEG) analysis was conducted on myocardial infarction (MI) datasets obtained from the Gene Expression Omnibus. Gene enrichment and molecular simulation studies were done to focus on apoptotic pathways. The computational findings were validated through In vitro experiments on H9C2 cardiomyocytes subjected to 8 h of hypoxia followed by 24 h of reoxygenation. Antioxidant enzyme levels (catalase, GST, GSH-Px, and SOD), mitochondrial membrane potential (ΔΨm), caspase-3 activity, and the expression of CASP3, MAPK8, JAK2, and BCL2L1 were assessed. ResultsCinnamoyl imidazole has demonstrated favourable pharmacokinetic properties, characterized by high gastrointestinal absorption and low toxicity with negative toxicity for organ endpoints. Molecular docking studies revealed the strong binding affinities for CASP3, MAPK8, and JAK2. In vitro results showed a significant increase in cell viability (94.7 % at 10 μM, p < 0.001) and antioxidant enzyme activity, along with a 64.3 % reduction in caspase-3 activity at 1000 μM (p < 0.01). Cinnamoyl imidazole treatment preserved mitochondrial membrane potential, downregulated pro-apoptotic genes CASP3 and MAPK8, and upregulated the anti-apoptotic gene BCL2L1. ConclusionCinnamoyl imidazole effectively mitigates oxidative stress and apoptosis in H/R-induced H9C2 cells, enhancing cell viability and antioxidant defenses while maintaining mitochondrial integrity.

Unlocking the potential of green synthesis: biogenic silver nanoparticles enhance biomass and bioactive chemicals in Ricinus communis Callus

Harnessing the power of nature, this study delves into the remarkable influence of biosynthesized silver nanoparticles (AgNPs) on biomass production and bioactive chemical synthesis in Ricinus communis callus. Leveraging the eco-friendly properties of Calligonum comosum leaf aqueous extract as both reducing and capping agents, the synthesis of AgNPs was meticulously characterized through an array of analytical techniques, including FTIR, UV-vis spectroscopy, XRD, SEM, TEM, and EDS, confirming the triumphant creation of biogenic AgNPs. Unveiling a landscape of possibilities, the assessment of R. communis biomass and phytochemical substances unraveled intriguing insights. Results unveiled a resounding enhancement in biomass production upon the introduction of biosynthesized AgNPs to the plant media. Noteworthy is the revelation that increasing concentrations of silver NPs acted as catalysts for heightened plant growth and enriched physiological parameters. Moreover, the application of silver nitride elicited a profound amplification in both biomass and antioxidant enzyme activities within plant cells. However, amidst these triumphs, a curious observation emerged: the activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) exhibited a notable decline with escalating doses of AgNPs. In essence, this groundbreaking study not only underscores the potential of biosynthesized AgNPs to orchestrate a symphony of growth and biochemical synthesis within R. communis callus but also beckons forth an era of exploration. By charting a course for future research, it beckons scientists to delve deeper into the intricate pathways of phytochemical production and bioactive molecule synthesis under the influence of AgNPs.

Augmenting Rice Defenses: Exogenous Calcium Elevates GABA Levels Against WBPH Infestation

This study investigates the impact of exogenous calcium and gamma-aminobutyric acid (GABA) supplementation on rice growth and stress tolerance under white-backed planthopper (WBPH) infestation. We evaluated several phenotypic traits, including shoot/root length, leaf width, tiller number, panicle length, and relative water content, alongside physiological markers such as oxidative stress indicators, antioxidant enzymes activities, hormonal levels, and amino acids biosynthesis. Our results indicate that WBPH stress significantly reduces growth parameters but calcium and GABA supplementation markedly enhance shoot length (by 26% and 36%) and root length (by 38% and 64%), respectively, compared to WBPH-infested plants. Both supplementations also reduced oxidative stress, as evidenced by decreased H2O2 and O2•− levels and a lower electrolyte leakage. Notably, calcium and GABA treatments increased antioxidant enzyme activities, with GABA boosting catalase (CAT) activity by 800%, peroxidase (POD) by 144%, and superoxide dismutase (SOD) by 62% under WBPH stress. Additionally, calcium and GABA enhanced the accumulation of stress hormones (abscisic acid ABA) and salicylic acid (SA) and promoted stomatal closure, contributing to improved water conservation. This study reveals that calcium regulates the GABA shunt pathway, significantly increasing GABA and succinate levels in both root and shoot. Furthermore, calcium and GABA supplementation enhance the biosynthesis of key amino acids and improve ion homeostasis, particularly elevating calcium (Ca), iron (Fe), and magnesium (Mg) levels under WBPH stress. Overall, this study highlights the potential of exogenous calcium and GABA as effective strategies for enhancing rice plant tolerance to WBPH infestation by modulating various physiological and biochemical mechanisms. Further research is warranted to fully elucidate the underlying mechanisms of action.

Polyphenol-rich Ocimum gratissimum leaf extract attenuates angiotensin-converting enzyme activity and impaired endothelial vascular function in diabetic rats

Endothelial vascular dysfunctions are prevalent among diabetic patients, significantly impacting their quality of life and prognosis. This study examined the effects of polyphenol-rich extracts from Ocimum gratissimum leaves on oxidative stress markers, serum lipid profiles, and angiotensin-converting enzyme activity in diabetic cardiac tissue. Forty Wistar rats (150–220 g) were divided into five groups: normal control, diabetic control, low-dose Ocimum gratissimum (122.46 mg/kg), medium-dose Ocimum gratissimum (244.98 mg/kg), and a positive control (standard diabetic drug). All rats except the normal control group were made diabetic via an intraperitoneal injection of 50 mg/kg streptozotocin, followed by 28 days of extract administration. Diabetes induction led to a significant (p&lt;0.05) disruptions in lipid profiles, oxidative stress markers, and ACE activity. Treatment with Ocimum gratissimum extracts at both doses significantly (p&lt;0.05) decreased triglyceride, low-density lipoprotein cholesterol, and very-low-density lipoprotein cholesterol levels while increasing high-density lipoprotein cholesterol. Lipid peroxidation marker, malondialdehyde, was significantly (p&lt;0.05) decreased, and antioxidant enzyme activities significantly (p&lt;0.005) improved. ACE activity was significantly (p&lt;0.05) reduced, approaching control levels. These results suggest that the polyphenol-rich extract of Ocimum gratissimum exerts antioxidant and cardio-protective effects, improving vascular functions in diabetic rats by improving lipid profiles, reducing oxidative stress, and suppressing ACE activity.

Hydrogen Gas Inhalation Alleviates Airway Inflammation and Oxidative Stress on Ovalbumin-Induced Asthmatic BALB/c Mouse Model

Airway inflammatory diseases, such as asthma, are a global public health concern owing to their chronic inflammatory effects on the respiratory mucosa. Molecular hydrogen (H2) has recently been recognized for its antioxidant and anti-inflammatory properties. In this study, we examined the therapeutic potential of H2 in airway inflammation using an ovalbumin (OVA)-induced BALB/c mouse model of allergic asthma. Female BALB/c mice were sensitized and challenged with OVA to induce airway inflammation, and 30 mice were randomly divided into five groups: NT (non-treatment), HTC (3% H2 treatment only), NC (negative control, OVA only), PC (positive control, OVA + intranasal 1 mg/mL salbutamol 50 μL), and HT (H2 treatment, OVA + inhaled 3% H2). Various inflammatory and oxidative stress (OS)-induced markers such as white blood cells (WBCs) and their differential counts, lung histology, cytokine levels such as interleukin (IL)-4, (IL)-5, (IL)-13, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), granulocyte-macrophage colony-stimulating factor (GM-CSF), (IL)-10, reactive oxygen species (ROS), nitric oxide (NO), glutathione peroxidase (GPx), and catalase (CAT), and total immunoglobulin E (IgE) levels were investigated. Our results showed that inhaled H2 significantly reduced inflammatory cell infiltration, OS markers, and pro-inflammatory cytokine expression while upregulating antioxidant enzyme activity. Furthermore, H2 also significantly decreased serum IgE levels, a marker of allergic inflammation. Collectively, our findings suggest that H2 inhalation is a promising treatment option for airway inflammation, offering a novel approach with potential clinical applications.

Seawater-induced Salinity Enhances Antioxidant Capacity by Modulating Morpho-physiological and Biochemical Responses in Catharanthus roseus

Salt stress impedes plant growth and development due to several factors, including the generation of cellular oxidative stressors. This study aimed to assess the impacts of seawater-induced salinity on the plant development, physio-biochemical responses, and antioxidant capacity of Catharanthus roseus grown in a variety of seawater (4, 8, and 12 dS/m) for varying durations (60, 90, and 120 days). The experiment was laid out in a randomized complete block design with five replications. The results demonstrated that C. roseus successfully endured moderate salinity (8 dS/m) by maintaining plant height, number of leaves, branches, relative water content, and chlorophyll content with a minimum drop in dry biomass (25%) in a time- and dose-dependent approach. Furthermore, greater proline and soluble sugar contents suggested that C. roseus possessed enhanced osmoprotective capabilities to counteract osmotic stress caused by salinity. Conversely, all growth indicators decreased significantly at high salinity (12 dS/m). Increased levels of antioxidant enzyme activity catalase and ascorbate peroxidase, phenol and flavonoid, 2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid indicate a coordinated function for antioxidant components in regulating reactive oxygen species (ROS) at low (4 dS/m) and moderate (8 dS/m) salinities. In contrast, excessive salinity (12 dS/m) led to a burst of ROS, as seen by elevated levels of hydrogen peroxide, malondialdehyde, and electrolyte leakage that greatly reduced total dry matter (72%), especially on days 120. The ion studies on plants subjected to salinity revealed that most Na+ remained in the roots. In contrast, most K+, Ca2+, and Mg2+ are deposited more firmly in the leaves than in the roots. The findings imply that C. roseus may tolerate moderate salinity (8 dS/m) owing to its enhanced antioxidant defense system and osmolytes, which trigger antioxidant enzymes and maintain ionic balance.

Taxifolin ameliorates the D-galactose-induced aging of mouse hippocampal neurons HT-22 cells through modulating SIRT1/p53 and PI3K/AKT signaling pathways

By establishing an in vitro model of D-Gal-induced brain neuronal cell (HT-22) senescence, it was found that TAX treatment significantly increased the activities of SOD and GSH, while decreasing MDA levels in aging HT-22 cells, indicating that TAX effectively restored the total antioxidant capacity and antioxidant enzyme activity of aging HT-22 cells induced by D-Gal, and attenuated cellular oxidative stress injury. In addition, taxifolin could also protect HT-22 cells from aging by up-regulating SIRT1 while reducing the expression of Ac-p53, indicating that TAX may be an active substance that can effectively delay cell aging.

Effect of lead on photosynthetic pigments, antioxidant responses, metabolomics, thalli morphology and cell ultrastructure of Iridaea cordata (Rhodophyta) from Antarctica

Over the past decades, the concern about lead pollution in marine environments has increased due to its remarkable toxicity, even at low concentrations. Lead is one of the significant contaminants arising from human activities in Antarctica. However, its effects on polar photosynthetic organisms are poorly known. This work aims to evaluate the effects of two different environmental concentrations of lead (10 μg/L and 50 μg/L) on pigment content, antioxidant enzyme activities (catalase, superoxide dismutase, ascorbate peroxidase and glutathione–S–transferase), metabolome, thalli morphology and cell ultrastructure of the red seaweed Iridaea cordata (Turner) Bory from Terra Nova Bay (Ross Sea, Antarctica). The results highlighted that lead exposure decreased phycocyanin and phycoerythrin content, starting from 10 μg/L, while induced carotenoid accumulation at 50 μg/L. Catalase, ascorbate peroxidase, and superoxide dismutase activities generally increased after lead exposure and distinct biochemical features were identified in the control and treatment groups. Further lead–related effects on cell ultrastructure comprised floridean starch accumulation and plastoglobuli formation. Overall, our results suggested that the enhanced formation of reactive oxygen species in response to lead altered the photosynthetic pigment pattern, antioxidant defenses, metabolome and ultrastructure of I. cordata.