Exogenous ascorbic acid as a potent regulator of antioxidants, osmo-protectants, and lipid peroxidation in pea under salt stress.

Pea (Pisum sativum L.), a globally cultivated leguminous crop valued for its nutritional and economic significance, faces a critical challenge of soil salinity, which significantly hampers crop growth and production worldwide. A pot experiment was carried out in the Botanical Garden, The Islamia University of Bahawalpur to alleviate the negative impacts of sodium chloride (NaCl) on pea through foliar application of ascorbic acid (AsA). Two pea varieties Meteor (V1) and Sarsabz (V2) were tested against salinity, i.e. 0 mM NaCl (Control) and 100 mM NaCl. Three levels of ascorbic acid 0 (Control), 5 and 10 mM were applied through foliar spray. The experimental design was completely randomized (CRD) with three replicates. Salt stress resulted in the suppression of growth, photosynthetic activity, and yield attributes in pea plants. However, the application of AsA treatments effectively alleviated these inhibitory effects. Under stress conditions, the application of AsA treatment led to a substantial increase in chlorophyll a (41.1%), chl. b (56.1%), total chl. contents (44.6%) and carotenoids (58.4%). Under salt stress, there was an increase in Na+ accumulation, lipid peroxidation, and the generation of reactive oxygen species (ROS). However, the application of AsA increased the contents of proline (26.9%), endogenous AsA (23.1%), total soluble sugars (17.1%), total phenolics (29.7%), and enzymatic antioxidants i.e. SOD (22.3%), POD (34.1%) and CAT (39%) in both varieties under stress. Salinity reduced the yield attributes while foliarly applied AsA increased the pod length (38.7%), number of pods per plant (40%) and 100 seed weight (45.2%). To sum up, the application of AsA alleviated salt-induced damage in pea plants by enhancing photosynthetic pigments, both enzymatic and non-enzymatic activities, maintaining ion homeostasis, and reducing excessive ROS accumulation through the limitation of lipid peroxidation. Overall, V2 (Sarsabz) performed better as compared to the V1 (Meteor).

Cold atmospheric plasma enhances morphological and biochemical attributes of tomato seedlings.

Cold atmospheric plasma (CAP) is a physical technology with notable effects on living organisms. In the present study, tomato seeds (Solanum lycopersicum var. Bassimo Mill.) were exposed to CAP for various time intervals, ranging from 1 to 5 min, in both continuous and intermittent periods, and were compared with a control group that received no CAP treatment. Seedlings grown from treated seeds exhibited improvements in levels of growth traits, photosynthetic pigments, and metabolite contents when compared to the control group. Seedlings from seeds treated with S04 displayed significant increases in shoot and root lengths, by 32.45% and 20.60% respectively, compared to the control group. Moreover, seedlings from seeds treated with S01 showed a 101.90% increase in total protein, whereas those treated with S02 experienced a 119.52% increase in carbohydrate content. These findings highlight the substantial improvements in growth characteristics, photosynthetic pigments, and metabolite levels in seedlings from treated seeds relative to controls. Total antioxidant capacity was boosted by CAP exposure. The activities of enzymes including superoxide dismutase, catalase, and peroxidases were stimulated by S02 and exceeded control treatment by (177.48%, 137.41%, and 103.32%), respectively. Additionally, exposure to S04 increased the levels of non-enzymatic antioxidants like flavonoids, phenolics, saponins, and tannins over the control group (38.08%, 30.10%, 117.19%, and 94.44%), respectively. Our results indicate that CAP-seed priming is an innovative and cost-effective approach to enhance the growth, bioactive components, and yield of tomato seedlings.

Exploring the mechanism of transformation in Acacia nilotica (Linn.) triggered by colchicine seed treatment.

BACKGROUND: Acacia nilotica Linn. is a widely distributed tree known for its applications in post-harvest and medicinal horticulture. However, its seed-based growth is relatively slow. Seed is a vital component for the propagation of A. nilotica due to its cost-effectiveness, genetic diversity, and ease of handling. Colchicine, commonly used for polyploidy induction in plants, may act as a pollutant at elevated levels. Its optimal concentration for Acacia nilotica's improved growth and development has not yet been determined, and the precise mechanism underlying this phenomenon has not been established. Therefore, this study investigated the impact of optimized colchicine (0.07%) seed treatment on A. nilotica's morphological, anatomical, physiological, fluorescent, and biochemical attributes under controlled conditions, comparing it with a control. RESULTS: Colchicine seed treatment significantly improved various plant attributes compared to control. This included increased shoot length (84.6%), root length (53.5%), shoot fresh weight (59.1%), root fresh weight (42.8%), shoot dry weight (51.5%), root dry weight (40%), fresh biomass (23.6%), stomatal size (35.9%), stomatal density (41.7%), stomatal index (51.2%), leaf thickness (11 times), leaf angle (2.4 times), photosynthetic rate (40%), water use efficiency (2.2 times), substomatal CO2 (36.6%), quantum yield of photosystem II (13.1%), proton flux (3.1 times), proton conductivity (2.3 times), linear electron flow (46.7%), enzymatic activities of catalase (25%), superoxide dismutase (33%), peroxidase (13.5%), and ascorbate peroxidase (28%), 2,2-diphenyl-1-picrylhydrazyl-radical scavenging activities(23%), total antioxidant capacity (59%), total phenolic (23%), and flavonoid content (37%) with less number of days to 80% germination (57.1%), transpiration rate (53.9%), stomatal conductance (67.1%), non-photochemical quenching (82.8%), non-regulatory energy dissipation (24.3%), and H2O2 (25%) and O-2 levels (30%). CONCLUSION: These findings elucidate the intricate mechanism behind the morphological, anatomical, physiological, fluorescent, and biochemical transformative effects of colchicine seed treatment on Acacia nilotica Linn. and offer valuable insights for quick production of A. nilotica's plants with modification and enhancement from seeds through an eco-friendly approach.

Sodium nitroprusside modulates oxidative and nitrosative processes in Lycopersicum esculentum L. under drought stress.

KEY MESSAGE: Sodium nitroprusside mediates drought stress responses in tomatoes by modulating nitrosative and oxidative pathways, highlighting the interplay between nitric oxide, hydrogen sulfide, and antioxidant systems for enhanced drought tolerance. While nitric oxide (NO), a signalling molecule, enhances plant tolerance to abiotic stresses, its precise contribution to improving tomato tolerance to drought stress (DS) through modulating oxide-nitrosative processes is not yet fully understood. We aimed to examine the interaction of NO and nitrosative signaling, revealing how sodium nitroprusside (SNP) could mitigate the effects of DS on tomatoes. DS-seedlings endured 12% polyethylene glycol (PEG) in a 10% nutrient solution (NS) for 2 days, then transitioned to half-strength NS for 10 days alongside control plants. DS reduced total plant dry weight, chlorophyll a and b, Fv/Fm, leaf water potential (ΨI), and relative water content, but improved hydrogen peroxide (H2O2), proline, and NO content. The SNP reduced the DS-induced H2O2 generation by reducing thiol (-SH) and the carbonyl (-CO) groups. SNP increased not only NO but also the activity of L-cysteine desulfhydrase (L-DES), leading to the generation of H2S. Decreases in S-nitrosoglutathione reductase (GSNOR) and NADPH oxidase (NOX) suggest a potential regulatory mechanism in which S-nitrosylation [formation of S-nitrosothiol (SNO)] may influence protein function and signaling pathways during DS. Moreover, SNP improved ascorbate (AsA) and glutathione (GSH) and reduced oxidized glutathione (GSSG) levels in tomato plants under drought. Furthermore, the interaction of NO and H2S, mediated by L-DES activity, may serve as a vital cross-talk mechanism impacting plant responses to DS. Understanding these signaling interactions is crucial for developing innovative drought-tolerance strategies in crops.

Unraveling the underlying mechanisms of biochemical, physiological, and growth responses of two pea (Pisum sativum L.) cultivars under simulated acid rain-induced oxidative stress.

The current experiment was designed to evaluate the ramifications of simulated acid rain (SAR) on two pea (Pisum sativum L.) cultivars, Kashi Samridhi (Samridhi) and Kashi Nandini (Nandini), to decipher the intraspecific variations in defence mechanism considering the current scenario of rapid anthropogenic activities leading to increase in rain acidity. The pea cultivars were subjected to SAR of pH 7 (Control), 5.6, 5.0, and 4.5 under field conditions. SAR increased active oxygen species and malondialdehyde content due to increased lipid peroxidation in both cultivars; however, the increment intensity was more remarkable in Samridhi at the later growth stage. Ascorbic acid, thiol, and flavonoids were significantly increased in cultivar Nandini, along with increased peroxidase and superoxide dismutase activities. Total phenolics, glutathione reductase, and ascorbate peroxidase activities were enhanced considerably in Samridhi than in Nandini under SAR treatments. Higher stomatal density and stomatal size in Samridhi prompted greater acidic particles influx which further damaged the chloroplast and mitochondria. The present study concludes that cultivar Nandini is more proficient in inducing defence responses by elevating non-enzymatic antioxidants than Samridhi. Non-enzymatic linked defence mechanisms are more metabolically expensive, leading to less biomass accumulation in Nandini. The study depicted that innate defence responses, particularly the role of non-enzymatic antioxidants, governed the sensitivity level of cultivars towards SAR stress. Further, findings also contribute to bridging the knowledge gap regarding the responses of tropical and subtropical crops to acid rain. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-024-01494-x.

Tolerance mechanisms to aluminum in popcorn inbred lines involving aluminum compartmentalization and ascorbate-glutathione redox pathway.

MAIN CONCLUSION: Inbred line 11-133 of popcorn showed the lowest apoplast Al and total Al concentrations and Al-lumogallion complex, associated with a more efficient antioxidant system, mainly due to glutathione metabolism. Popcorn (Zea mays L. var. everta) is largely intended for human consumption. About 40% of the world's arable soils are acidic. In soils acidic, aluminum (Al) ionizes producing the trivalent cation, which is highly toxic to plants. Hence, this work aimed to: (1) evaluate the Al toxicity sites and its effect on the structure of the root tips, (2) quantify Al concentrations in the apoplast and symplast of the roots, and (3) to elucidate the modulation on the activity of antioxidant enzymes and metabolites of the ascorbate-glutathione cycle in two popcorn inbred lines (ILs) 11-133 and 11-60, classified as tolerant and sensitive to this metal, respectively. Aluminum toxicity did not affect the shoot growth; however, there was a yellowing of the oldest leaf blade only in 11-60. The better performance of 11-133 is related to lower apoplastic and total Al concentrations and Al accumulation in the root associated with a lower fluorescence of Al-lumogallion complex at the root tip, indicating the presence of mechanisms of chelation with this metal. Consequently, this IL showed less change in root morphoanatomy and lower reactive oxygen species and malondialdehyde content, which are associated with a more efficient enzymatic and non-enzymatic system, mainly due to the higher content of the glutathione metabolite and the higher activities of superoxide dismutase, monodehydroascorbate reductase, dehydroascorbate reductase, γ-glutamylcysteine synthetase, and glutathione peroxidase enzymes. Thus, these findings illustrated above indicate how internal mechanisms of detoxification respond to Al in popcorn, which can be used as tolerance biomarkers.

Comparison of selected prooxidant-antioxidant balance and bone metabolism indicators and BDNF levels between older women with different levels of physical activity.

BACKGROUND: Given a lack of studies precisely indicating how many steps elderly people should take daily for their antioxidant defence, bone metabolism, and cognitive abilities to improve, our study set out to compare the selected antioxidant, prooxidant, bone turnover, and BDNF indicators between elderly women differing in physical activity (PA) measured by the daily number of steps. METHODS: The PA levels of 62 women aged 72.1 ± 5.4 years were assessed based on their daily number of steps and then were used to allocate the participants to three groups: group I (n = 18; <5,000 steps a day); group II (n = 22; from 5,000 to 9,999 steps a day); and group III (n = 22; ≥10,000 steps a day). Blood samples were collected from the participants in early morning hours and subjected to biochemical analysis for prooxidant-antioxidant balance indicators (SOD, CAT, GPx, GR, GSH, UA, MDA and TOS/TOC), bone metabolism indicators (Ca, 25-OH vitamin D, osteocalcin, CTX-I, and PTH), and BDNF levels. RESULTS: The groups were not statistically significantly different in the activity of SOD, CAT, GPx, and GR, but their concentrations of GSH (H = 22.10, p < 0.001) and UA (H = 12.20, p = 0.002) proved to be significantly associated with the groups' daily PA. The between-group differences in the concentrations of MDA and TOS/TOC were not significant, with both these indicators tending to take higher values in group I than in groups II and III. Significant differences between the groups were established for the concentrations of 25-OH vitamin D (H = 24.21, p < 0.001), osteocalcin (H = 7.88, p = 0.019), CTX-I (H = 12.91, p = 0.002), and BDNF (H = 14.47, p = 0.001), but not for Ca and PTH. CONCLUSIONS: Significantly higher concentrations of GSH, slightly lower oxidative stress indicators, significantly higher BDNF levels, and moderately better bone turnover indicators and resorption markers in the group taking more than 5,000 steps a day suggest that this level of PA can promote successful aging. More research is, however, needed to confirm this finding.

Exploring the Physiological Multiplicity of Native Microalgae from the Ecuadorian Highland, Italian Lowland and Indoor Locations in Response to UV-B.

The differential effects of UV-B on the inhibition or activation of protective mechanisms to maintain cells photosynthetically active were investigated in native microalgae. Four strains were used, including two Chlorella sorokiniana strains, F4 and LG1, isolated from a Mediterranean inland swamp and a recycled cigarette butt's substrate, respectively, and two isolates from an Ecuadorian highland lake related to Pectinodesmus pectinatus (PEC) and Ettlia pseudoalveolaris (ETI). Monocultures were exposed to acute UV-B (1.7 W m-2) over 18 h under controlled conditions. UV-B-untreated microalgae were used as the control. Comparative physiological responses, including photosynthetic pigments, non-enzymatic antioxidants, and chlorophyll a fluorescence, were evaluated at specific time points. Results showed that UV-B significantly compromised all the physiological parameters in F4, thereby resulting in the most UV-B-sensitive strain. Contrarily, UV-B exposure did not lead to changes in the PEC physiological traits, resulting in the best UV-B-resistant strain. This could be attributed to the acclimation to high light habitat, where maintaining a constitutive phenotype (at the photosynthetic level) is strategically advantageous. Differently, LG1 and ETI at 12 h of UV-B exposure showed different UV-B responses, which is probably related to acclimation, where in LG1, the pigments were recovered, and the antioxidants were still functioning, while in ETI, the accumulation of pigments and antioxidants was increased to avoid further photodamage. Consequently, the prolonged exposure in LG1 and ETI resulted in species-specific metabolic regulation (e.g., non-enzymatic antioxidants) in order to constrain full photoinhibition under acute UV-B.

The Effect of Acute Caffeine Intake on Resistance Training Volume, Prooxidant-Antioxidant Balance and Muscle Damage Markers Following a Session of Full-Body Resistance Exercise in Resistance-Trained Men Habituated to Caffeine.

No previous study has analyzed the impact of caffeine intake on prooxidant-antioxidant balance and muscle damage following resistance exercise. The aim of this study was to determine the effect of 3 mg/kg of caffeine on the number of repetitions and the prooxidant-antioxidant balance and muscle damage after a session of full-body resistance exercise. Ten resistance-trained men habituated to caffeine participated in a randomized, crossover and double-blind experiment. Each participant performed two identical resistance training sessions after the intake of 3 mg/kg of caffeine or a placebo. Blood was collected before and 60 min after substance intake, just after exercise, 60 minutes after exercise, and 24 hours after testing to evaluate the activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase), non-enzymatic antioxidants (reduced glutathione, uric acid) levels of oxidative stress markers (plasma malondialdehyde) and muscle damage markers (creatine kinase, lactate dehydrogenase). There were no significant differences between placebo and caffeine conditions in the total number of repetitions (180 ± 15 vs 185 ± 14 repetitions, respectively; p = 0.276; Effect size [ES] = 0.34), the total time under tension (757 ± 71 vs 766 ± 56 s, respectively; p = 0.709; ES = 0.14) or the rating of perceived exertion (13.8 ± 2.7 vs 14.7 ± 2.7 a.u., respectively; p = 0.212; ES = 0.32). Reduced glutathione concentration obtained 1 hour after exercise was higher with caffeine than with placebo (p = 0.047), without significant difference between conditions for any other prooxidant-oxidant or muscle damage marker at any time point (p > 0.050 for all). The oral intake of 3 mg/kg of caffeine by resistance-trained men habituated to caffeine did not enhance the number of repetitions during a medium load full-body resistance training session to failure and had a minimal impact on the prooxidant-antioxidant balance and muscle damage. The study was registered prospectively at ClinicalTrials.gov with the following ID: NCT05230303.

Role of rhizobia in promoting non-enzymatic antioxidants to mitigate nitrogen-deficiency and nickel stresses in Pongamia pinnata.

The contribution of rhizobia in the mitigation of non-enzymatic antioxidants against nitrogen deficiency and heavy metal toxicity for legume plant is not clear. Therefore, it is hypothesized that the inoculation of rhizobia could mitigate nitrogen deficiency and nickel (Ni) stresses in P. pinnata tissues by enhancing the formation of certain non-enzymatic antioxidants. The effect of symbiotic nitrogen-fixing rhizobia on the mitigation of nitrogen-deficiency and Ni stresses in P. pinnata was evaluated by inoculating two different rhizobia, i.e., Rhizobium pisi PZHK2 and Ochrobacterium pseudogrignonense PZHK4, around the rhizosphere of P. pinnata grown in soil containing 40 mg kg-1 Ni2+ and without nitrogen addition. The inoculation with both rhizobial strains promoted the growth of P. pinnata under nickel stress or nitrogen-deficiency condition, increased nitrogen content in all plant tissues and nickel content in shoots and leaves, but reduced nickel accumulation in roots. The four non-enzymatic antioxidants including glutathione (GSH), proanthocyanidin (OPC), ascorbic acid (ASA) and flavonoids (FLA) distributed in roots, shoots and leaves were followed in descending order: GSH > OPC > ASA > FLA. The four non-enzymatic antioxidants showed different levels of change under the nitrogen-deficiency and nickel stresses and in the non-stress control. The inoculation of PZHK2 and PZHK4 significantly (p < 0.05) increased the four non-enzymatic antioxidants in P. pinnata tissues, especially in roots. Some non-enzymatic antioxidants showed correlations with nickel or nitrogen in P. pinnata tissues, and the four non-enzymatic antioxidants also had correlations among each other. Therefore, this research revealed an excellent role of rhizobia in promoting non-enzymatic antioxidants to mitigate nitrogen-deficiency or nickel stress for P. pinnata.

Bioaccumulation of Silver and Impairment of Vital Organs in Clarias gariepinus from Co-Exposure to Silver Nanoparticles and Cow Dung Contamination.

This study reports the implications of silver nanoparticles (AgNPs) and cow-dung contamination on water quality and oxidative perturbations in antioxidant biomarkers in the exposed Clarias gariepinus. Sixteen samples of C. gariepinus were exposed to fresh-water, 0.75 mg/mL each of AgNPs, cow-dung and a mixture of AgNPs-cow dung dosed water for 10 days. Cow-dung significantly (p < 0.05) depleted dissolved oxygen (DO) and increased biochemical oxygen demand (BOD) by 14% and 75% respectively. The trends of abundance and bioaccumulation of Ag in C. gariepinus exposed to different treatments followed kidney > muscle > gill > liver, implying the kidney was the worst affected organ. The AgNPs significantly (p < 0.05) perturbed vital organs in C. gariepinus by altering activities of antioxidant biomarkers, whereas AgNPs-cow dung had reduced perturbations implying organic matter bound Ag+ to reduce toxicity. These results conclude that AgNPs posed a challenging environment for C. gariepinus to thrive.

Effects of Midazolam on Antioxidant Levels, Biochemical and Metabolic Parameters in Eurygaster integriceps Puton (Hemiptera: Scutelleridae) Eggs Parasitized by Trissolcus semistriatus Nees (Hymenoptera: Scelionidae).

Eurygaster integriceps Puton (Hemiptera: Scutelleridae) is among the most important insect pests of wheat (Triticum sativum L.) and barley (Hordeum vulgare L.) grown in the Middle East. Biological and chemical methods are insufficient to control E. integriceps populations below economic thresholds. In this study, we investigated the effects of midazolam, a clinical drug, on selected metabolic enzyme activity, antioxidant levels, and biochemical parameters in E. integriceps eggs parasitized by Trissolcus semistriatus Nees (Hymenoptera: Scelionidae). Increasing concentrations of midazolam caused cell damage in the parasitized eggs due to its oxidative effects. Transferase enzymes, such as, aspartate transferase, alanine transferase, and gamma glutamyl transferase activities were altered following exposure. Metabolic enzymes, such as, creatine kinase, alkaline phosphatase, amylase, and lactate dehydrogenase also were adversely affected. Levels of the non-enzymatic antioxidants uric acid, bilirubin, and albumin also were altered.

Pathophysiological effects of Klebsiella pneumoniae infection on Galleria mellonella as an invertebrate model organism.

Klebsiella pneumoniae is an important human pathogen causing urinary tract infections and pneumonia. Due to the increase in resistant strains and being an opportunistic pathogen, it is very important to determine the virulence process, the cellular damage it causes in the host and the immunological response level of the host. In this study, invertebrate infection model Galleria mellonella larvae were used to investigate cellular damage, antioxidant response and changes in biochemical parameters due to K. pneumoniae infection. The activity of cell damage indicators alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase increased in hemolymph of G. mellonella larvae due to K. pneumoniae virulence. Creatine kinase, alkaline phosphatase, gamma glutamyl transferase and amylase activities were increased to regulate the disrupted energy metabolism due to infection. As a result of the damage caused by K. pneumoniae infection, changes occurred in the amount of non-enzymatic antioxidants, uric acid, bilirubin and albumin. Due to K. pneumoniae infection, the amount of calcium, potassium, magnesium and phosphorus altered. This study showed that G. mellonella larvae was important infection model in the investigation of infectious cell damage and physiological effects, given the opportunistic nature of the K. pneumoniae pathogen and the lack of adequate animal models.

Flight training and dietary antioxidants have mixed effects on the oxidative status of multiple tissues in a female migratory songbird.

Birds, like other vertebrates, rely on a robust antioxidant system to protect themselves against oxidative imbalance caused by energy-intensive activities such as flying. Such oxidative challenges may be especially acute for females during spring migration, as they must pay the oxidative costs of flight while preparing for reproduction; however, little previous work has examined how the antioxidant system of female spring migrants responds to dietary antioxidants and the oxidative challenges of regular flying. We fed two diets to female European starlings, one supplemented with a dietary antioxidant and one without, and then flew them daily in a windtunnel for 2 weeks during the autumn and spring migration periods. We measured the activity of enzymatic antioxidants (glutathione peroxidase, superoxide dismutase and catalase), non-enzymatic antioxidant capacity (ORAC) and markers of oxidative damage (protein carbonyls and lipid hydroperoxides) in four tissues: pectoralis, leg muscle, liver and heart. Dietary antioxidants affected enzymatic antioxidant activity and lipid damage in the heart, non-enzymatic antioxidant capacity in the pectoralis, and protein damage in leg muscle. In general, birds not fed the antioxidant supplement appeared to incur increased oxidative damage while upregulating non-enzymatic and enzymatic antioxidant activity, though these effects were strongly tissue specific. We also found trends for diet×training interactions for enzymatic antioxidant activity in the heart and leg muscle. Flight training may condition the antioxidant system of females to dynamically respond to oxidative challenges, and females during spring migration may shift antioxidant allocation to reduce oxidative damage.

Controlled expression of the migratory phenotype affects oxidative status in birds.

High caloric intake can increase production of reactive oxygen and nitrogen species. We examined whether the emergence of the migratory phenotype, primarily signalled by increased food intake and fuelling, is accompanied by changes in oxidative status. We induced autumn migration followed by a non-migratory wintering phase in common quails (Coturnix coturnix). We compared three markers of oxidative status - oxidative damage to lipids expressed as thiobarbituric acid reactive substances (TBARS); superoxide dismutase (SOD); and glutathione peroxidase (GPx) - between birds sampled during the migratory and non-migratory phase. We found that the emergence of the migratory phenotype was associated with: (i) higher levels of TBARS in the liver; (ii) lower levels of SOD in red blood cells and, marginally, in the liver; (iii) higher levels of GPx in the pectoral muscle; and (iv) sex-specific changes in red blood cells and liver. We found no link between food intake and variation in markers of oxidative status in any of the tissues examined, despite food intake being higher in the migratory birds. However, the increase in body mass was positively correlated with muscle GPx activity as birds entered the pre-migratory fattening phase, while the amount of decrease in body mass was negatively correlated with muscle GPx as birds transitioned to the non-migratory phase. Such correlations were absent in red blood cells and liver. Our work suggests that during the emergence of the migratory phenotype, birds might strategically displace oxidative costs on the liver in order to safeguard the pectoral muscles, which have a fundamental role in successfully completing the migratory flight.

Photosynthesis, lipid peroxidation, and antioxidative responses of Helianthus annuus L. against chromium (VI) accumulation.

The present study was performed to address how Cr(VI) posed its toxicities on photosynthesis, lipid peroxidation, and its retaliation by antioxidative system of Helianthus annuus L. during Cr(VI) accumulation. For this, a pot experiment was performed wherein three different concentrations viz, 15, 30, and 60 mg Cr(VI) kg-1 soil were applied to Helianthus annuus L. at the time of seeds sowing. The results revealed that Cr(VI) accumulation was two to three folds higher in roots than in shoots which suggests that root is the major site for Cr(VI) accumulation. It was observed that with increasing doses of Cr(VI), growth indices hampered significantly, along with closure of stomata and damaged guard and epidermal cells. Photosynthetic pigments (chlorophyll a, chlorophyll b, carotenoids), leaf gaseous exchange parameters (A, E, GH2O), and PSII efficiency (Fv/Fm) worsened under Cr(VI) toxicity in dose dependent manner. Cr(VI) accumulation intensified the lipid peroxidation, too by triggering the MDA and H2O2 production, however, the plant responded well against the lipid peroxidation by enhancing the coordinated action of enzymatic (SOD, APX, GR) and non-enzymatic (GSH, AsA) antioxidants. In a nutshell, Helianthus annuus L. could be used as a potential Cr(VI) accumulator because of its good tolerance strategies against Cr(VI) toxicities.NOVELTY STATEMENT The results revealed that Cr(VI) accumulation was two to three folds higher in roots than in shoots which suggests that root is the major site for Cr(VI) accumulation. Photosynthetic pigments, leaf gaseous exchange parameters, and Fv/Fm worsened under Cr(VI) toxicity. Cr(VI) accumulation intensified lipid peroxidation by triggering MDA and H2O2 production, however, the plant responded well against the lipid peroxidation by enhancing the coordinated action of enzymatic and non-enzymatic antioxidants. In a nutshell, Helianthus annuus L. could be used as a potential Cr(VI) accumulator because of its good tolerance strategies against Cr(VI) toxicities.

The effect of NADPH oxidase inhibitor diphenyleneiodonium (DPI) and glutathione (GSH) on Isatis cappadocica, under Arsenic (As) toxicity.

The present work was conducted to assess the effects of arsenic (As, 1000 µM), diphenyleneiodonium (DPI, 10 µM) and reduced glutathione (GSH, 500 µM) on Isatis cappadocica. As treatment decreased plant growth and fresh and dry weight of shoot and root and also enhanced the accumulation of As. As stress also enhanced the oxidative stress biomarkers, hydrogen peroxide (H2O2) and malondialdehyde (MDA) content. However, the application of GSH decreased the content of H2O2 and MDA by 43% and 55%, respectively, as compared to As treatment. The antioxidants like superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathione S-transferase (GST) also enhanced with As stress. NADPH oxidase inhibitor, the DPI, enhances the effect of As toxicity by increasing the accumulation of As, H2O2, MDA. DPI also enhances the activity of antioxidant enzymes except GR and GST, However, the application GSH increased the plant growth and biomass yield, decreases accumulation of As, H2O2 and MDA content in As as well as As + DPI treated plants. The thiols content [total thiol (TT), non-protein thiol (NPT) protein thiols (PT), and glutathione (GSH)] were decreased in the As + DPI treatment but supplementation of GSH enhanced them. Novelty statement: The study reveals the beneficial role of GSH in mitigating the deleterious effects of Arsenic toxicity through its active involvement in the antioxidant metabolism, thiol synthesis and osmolyte accumulation. Apart from As, We provided the plants NADPH oxidase inhibitor, the diphenyleneiodonium (DPI), which boosts the As toxicity. At present, there is dearth of information pertaining to the effects of DPI on plants growth and their responses under heavy metal stress.GSH application reversed the effect of diphenyleneiodonium (DPI) under As stress preventing the oxidative damage to biomolecules through the modulation of different antioxidant enzymes. The application of GSH for As stressed soil could be a sustainable approach for crop production.

Changes in blood antioxidant status in American football players and soccer players over a training macrocycle.

BACKGROUND: The effectiveness of sport training programs should be assessed regularly against biochemical indices. This study assesses changes in the antioxidant status indices in American football players (AF) and soccer players (SP) over a training macrocycle. METHODS: The study was carried out with Poland's American Football League players (AF, n = 11, age 24.0 ± 3.7 years) and first-league soccer players (SP, n = 11, age 26.5 ± 3.8 years). Resting venous blood samples were collected from the players at the beginning of the three periods (preparatory, competition, and transition) making up the training macrocycle to determine the activity levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione reductase (GR), creatine kinase (CK), and lactate dehydrogenase (LDH), as well as the concentrations of non-enzymatic antioxidants (uric acid-UA and glutathione-GSH) and the levels of malondialdehyde (MDA). RESULTS: The period effect on SOD (p < 0.001), CAT (p < 0.05), GPx (p < 0.05), GSH (p < 0.0001) and UA (p < 0.0001), and the group × period interaction effect on SOD, CAT and GPx (p < 0.05), GSH (p < 0.001), and UA (p < 0.01) proved to be significant. Also significant were the group effect on MDA (p < 0.001) and LDH (p < 0.0001) and the period effect on MDA (p < 0.01) and LDH (p < 0.001). The activity of SOD and CAT and the concentration of GSH were higher in both AF (12%, 2%, and 15%, respectively) and SP (33%, 10%, and 42%) at the start of the competition period than in the preparatory period, but the concentration of MDA and the activity of CK and LDH was lower (0.8%, 29%, 5% (AF) and 2%, 11%, 5% (SP). The highest activity of GPx and LDH and the greatest concentrations of UA and MDA occurred in the early transition period. CONCLUSION: The study revealed an association between American footballers' and soccer players' training loads in the preparatory period and moderate improvements in their blood antioxidant status at the beginning of the competition period.

Evaluation of serum amino acids and non-enzymatic antioxidants in drug-naïve first-episode major depressive disorder.

BACKGROUND: The alterations of biological markers are thought to be effective tools to understand the pathophysiology and management of major depressive disorder (MDD). A lot of researches has implied many markers for depression, but any of them fully discovered the association between the markers and depression. The present study investigated the serum levels of amino acids and non-enzymatic antioxidants in major depression, and also explained their association with depression. METHODS: This study examined 247 MDD patients and 248 healthy controls (HCs) matched by age and sex. The Hamilton Depression Rating Scale (Ham-D) was used to all the participants to measure the severity of depression. Quantification of serum amino acids, vitamin A and E were carried out using the HPLC system whereas vitamin C levels were measured by UV-spectrophotometer. All the statistical analysis was performed by SPSS statistical software (version 23.0). The independent sample t-test, the Mann-Whitney U test, and the Fisher's exact test were applied to detect the group differences where a Bonferroni correction applied to the p value. RESULTS: It was observed that serum levels of four amino acids (methionine, phenylalanine, tryptophan, and tyrosine) along with three non-enzymatic antioxidants (vitamin A, E, and C) were significantly dropped in MDD patients compared to HCs (Cohen's d (d): - 0.45, - 0.50, - 0.68, - 0.21, - 0.27, - 0.65, and - 0.24, respectively). Furthermore, Ham-D scores of cases were negatively correlated with serum levels of methionine (r = - 0.155, p = 0.015) and tyrosine (r = - 0.172, p = 0.007). CONCLUSION: The present study suggests that lowered serum methionine, phenylalanine, tryptophan, tyrosine, and non-enzymatic antioxidants are associated with depression. The reduction of these parameters in MDD patients may be the consequence, and not the cause, of major depression.

Physiological and molecular mechanism of cadmium (Cd) tolerance at initial growth stage in rapeseed (Brassica napus L.).

Cadmium (Cd) contaminated soil has threatened plant growth and human health. Rapeseed (Brassica napus L.), an ideal plant for phytoremediation, is an important source of edible vegetable oil, vegetable, animal fodder, green manure and biodiesel. For safe utilization of Cd polluted soil, physiological, biochemical, and molecular techniques have been used to understand mechanisms of Cd tolerance in B. napus. However, most of these researches have concentrated on vegetative and adult stages, just a few reports focus on the initial growth stage. Here, the partitioning of cadmium, gene expression level and activity of enzymatic antioxidants of H18 (tolerant genotype) and P9 (sensitive genotype) were investigated under 0 and 30 mg/L Cd stress at seedling establishment stage. Results shown that the radicle length of H18 and P9 under Cd stress were decreased by 30.33 (0.01 < P < 0.05) and 88.89% (P < 0.01) respectively. Cd concentration at cotyledon not radicle and hypocotyl in P9 was significantly higher than that in H18. The expression level of BnaHMA4c, which plays a key role in root-to-shoot translocation of Cd, was extremely higher in P9 than in H18 under both normal and Cd stress conditions. We also found that SOD, CAT and POD were more active in responding to Cd stress after 48 h, and the activity of SOD and CAT in H18 were higher than that in P9 at all observed time points. In conclusion, high activity of enzymatic antioxidants at initial Cd stress stage is the main detoxification mechanism in Cd-tolerant rapeseed, while the higher Cd transfer coefficient, driven by higher expression level of BnaHMA4c is the main mechanism for surviving radicle from initial Cd toxicity in Cd-sensitive rapeseed.