Changes In Superoxide Dismutase Activity Research Articles

ANTIOXIDANT ACTIVITY OF HUMAN MIXED SALIVA IN NORM

It is known that the monitoring of superoxide dismutase and catalase activity allows to assess the level of influence of environmental situation in particular chemical factors of ecosystem on public health. "Oxidative stress" is one of the mechanisms of environmental influence on human organism. Considering complex character of catalase and superoxide dismutase activity change interpretation of the obtained results can be difficult, thus it is more effective to use integrated indices in particular, antioxidant activity. The aim of the study was to develop approaches to assessing the severity of "oxidative stress" by determining the activity of antioxidant enzymes and antioxidant activity of human saliva and study variations of these parameters in norm. It is shown that activity of individual antioxidant enzymes varies even during the day, and therefore the interpretation of these values і s difficult. Antioxidant activity can be a most promising indicator for assessing the intensity of the "oxidative stress" of biological fluids, such as saliva. Method of determining of antioxidant activity saliva is picked up using 2,6-dichlorophenolindophenol. Temporal and physiological characteristics are determined for the dynamics of saliva antioxidant activity in norm, the stability of this parameter is shown, taking into account age and gender characteristics.

Response of antioxidant enzymes to cadmium-induced cytotoxicity in rat cerebellar granule neurons

AbstractCadmium (Cd) accumulates in the brain and can damage neurons via complex processes involving oxidative stress induction. In this study we used a homogenous population of neurons which are cerebellar granule neurons (CGNs) to investigate damage induced by Cd and its effects on antioxidant enzyme activity. The exposure of CGNs to increasing concentrations of Cd (2.5 μM-100 μM) during 24 h, 48 h, or 72 h led to the induction of neuronal death in a dose- and exposure time-dependent manner. The necrotic and/or apoptotic pathway involved in the cell death trigged by Cd seems to depend on the concentration of Cd and the exposure time. In addition to its cell damage, Cd was shown to affect the activity of superoxide dismutase (SOD) and catalase (CAT) depending on the concentration of Cd and the exposure time. We also found that the exposure to Cd induces a bigger change in SOD activity than in CAT activity. Taken together, our findings explain, in part, the mechanism of Cd toxicity in a specific type of neuron which can provide information related to neurological pathologies ascribed to Cd toxicity.

Algae decorated TiO2/Ag hybrid nanofiber membrane with enhanced photocatalytic activity for Cr(VI) removal under visible light

Algae as an abundant natural biomass, more attention has been paid to explore its potential application in environmental pollutants treatment. This work prepared the algae-TiO2/Ag bionano hybrid material by loading algae cells on the ultrafine TiO2/Ag chitosan hybrid nanofiber mat. For the first time, the synergistic photocatalytic effect of fresh algae and TiO2/Ag nanomaterial was investigated by removal of Cr(VI). The addition of algae significantly improved the photo-removal of Cr(VI) in the system with TiO2/Ag hybrid nanomaterial under visible light irradiation. Meanwhile, the photocatalytic mechanism was studied. The photogenerated reactive oxygen species were quantified and the addition of algae apparently decreased the yields of OH to 31.0μM, while improved the yields of 1O2 and O2− in the reaction system with TiO2/Ag hybrid nanofiber mats. The change of superoxide dismutase activity and malondialdehyde content in algae indicated that TiO2/Ag could impose oxidative stress and cause lipid peroxidation in algae cells. During the course of irradiation, algae released substances could act as scavenger for holes, thus inhibited the recombination of hole/electron and enhanced the photocatalytic reduction of Cr(VI) by electrons on TiO2 surface. Algae was simultaneously photodegraded in the system and the resulting O2−, organic free radicals could promote the reduction of Cr(VI). This functional hybrid nanofiber mat was easily recovered and maintained a great photocatalytic activity on the five successive cycles. This algae-photocatalyst hybrid material has promising applications potential in heavy metal removal and organic pollutants treatment.

Toxicological and physiological effects of ethephon on the model organism, Galleria mellonella L. 1758 (Lepidoptera: Pyralidae)

Ethephon (ETF) has been used in agriculture as an ethylene releaser type of plant growth regulator. The aim of this work was to determine the ecotoxicological effects of ETF on the survival and the antioxidant metabolism of the insects using a model organism Galleria mellonella L. 1758. A toxicity test was performed to determine the lethal doses of ETF on larvae. According to probit assay, the LD 50 and LD 99 values for force fed larvae were 344 and 419 µg/5 µl, respectively, 30 d after treatment. Analyses performed with 10 doses ≤LD 50 at 24 and 48 h upon feeding larvae revealed that the malondialdehyde level increased at 300 and 330 µg/5 µl doses, whereas glutathione-S-transferase activity increased only with a 360 µg/5µl dose of ETF at 24 h. However, an increase in glutathione-S-transferase activity was evident at all ETF doses at 48 h. An increase in glutathione peroxidases activity was determined at 250, 300 and 330 µg/5µl at 24 and 48 h. All ETF doses caused an important increase in catalase activity at 24 h but remained unchanged at 48 h. Superoxide dismutase activity also elevated at doses >250 µg/5µl at 24 h when compared to the control. Same changes in superoxide dismutase activity were also observed at all doses of ETF except for 360 µg/5µl at 48 h. These results showed that ETF induced oxidative stress resulted in toxic effects that affected on the survival of model organism G. mellonella .

Increased Granulocyte Heparanase Activity in Neutrophils from Patients with Lupus Nephritis and Idiopathic Membranous Nephropathy

Heparanase is a β-glucuronidase that cleaves sugar chains of heparan sulfate proteoglycans. It is believed that heparanase may be involved in the pathogenesis of proteinuria. The aim of this study was to assess the significance of heparanase in the pathogenesis of particular glomerulonephritis types. The evaluation of heparanase activity in serum, urine, and granulocytes and superoxide dismutase (SOD) activity in granulocytes of patients with lupus nephritis (n = 17), membranous nephropathy (n = 11), IgA nephropathy (n = 12), focal and segmental glomerulosclerosis (n = 18), mesangiocapillary glomerulonephritis (n = 12) and in 19 healthy volunteers were performed. The heparanase activity in granulocytes of patients with lupus nephritis and membranous nephropathy was higher than heparanase activity in granulocytes in the control group (p = 0.02 in both cases). This is the first observation of this phenomenon. There was no difference between SOD activity in granulocytes of patients with all assessed types of glomerulonephritis and the control group. A positive correlation between heparanase activity in urine and double-strain DNA antibodies (r = 0.51; p = 0.04), and reverse correlations between heparanase in urine and hemolytic activity of the complement (r = −0.57; p = 0.03) in the lupus nephritis group, and between heparanase activity in granulocytes and serum total protein level (r = −0.69; p = 0.02) in membranous nephropathy were observed. Increase in heparanase activity without changes in superoxide dismutase activity in the granulocytes from patients with lupus nephritis and membranous nephropathy was observed. It may be used as one of the markers of these disease activities.

The toxic effect and bioaccumulation in aquatic oligochaete Limnodrilus hoffmeisteri after combined exposure to cadmium and perfluorooctane sulfonate at different pH values

Cadmium (Cd) and Perfluorooctane sulfonate (PFOS) have been detected in aquatic environment. In this study, we investigated the acute effect, bioaccumulation and oxidative stress status in the aquatic oligocheate Limnodrilus hoffmeisteri after exposure to Cd and PFOS at different pH values. In the studied pH range, acute Cd toxicity was significantly enhanced with pH increasing from 6.2 to 8.0, and the 48h-EC50 of Cd was (significantly) decreased in the presence of PFOS. Bioaccumulation analysis results show that the accumulated Cd/PFOS in single exposure group increased with increasing exposure concentrations, and co-exposure makes internal Cd concentration significantly lowered for Cd(0.1) group at pH 8.0. Significant changes in superoxide dismutase activity, glutathione level and malondialdehyde content were observed in single and combined treatments. Based on IBR value, single Cd and PFOS exposure caused largest damage to the antioxidant defense system at pH 8.0 and pH 6.2, respectively, while the harmful effects of joint exposure were always the “compromise” between single Cd and PFOS exposure. This work could provide useful information for the risk assessment of co-exposure to perfluorinated compounds and heavy metals in natural environment.

Serum paraoxonase 1 (PON1) activity and lipid metabolism parameters changes in different production cycle periods of Holstein-Friesian, Polish Red and Norwegian breeds.

We investigated the measurement of paraoxonase 1 (PON1), as a potential marker of redox state changes in dairy cows, its involvement in lipid metabolism and compared it with superoxide dismutase (SOD) activity changes. We also evaluated lipid metabolism parameters associated with dairy production. PON1 paraoxonase and arylesterase acitvities, SOD activity, beta-hydroxybutyrate (BHB), uric acid (UA), high density lipoprotein (HDL), low density lipoprotein (LDL), cholesterol and triglyceride concentrations were measured in Holstein-Friesian, Polish Red and Norwegian breeds serum in two production cycles. Our data showed a significant postpartum depletion in PON1 activity and lipoprotein and lipid products concentrations, with elevated BHB values. However, there were no significant changes in SOD activity and uric acid concentrations in Holstein-Friesian and Polish Red breeds after calving. At lactation peak there was a significant SOD activity decrease correlated with standardized PON1 activity depletion in all examined breeds. The results suggest that PON1 might be a better parameter for minimal redox state changes in serum, shortly after labour in the examined breeds.

Rutin, a flavonoid with antioxidant activity, improves plant salinity tolerance by regulating K+ retention and Na+ exclusion from leaf mesophyll in quinoa and broad beans.

The causal relationship between salinity and oxidative stress tolerance is well established, but specific downstream targets and the role of specific antioxidant compounds in controlling cellular ionic homeostasis remains elusive. In this work, we have compared antioxidant profiles of leaves of two quinoa genotypes contrasting in their salt tolerance, with the aim of understanding the role of enzymatic and non-enzymatic antioxidants in salinity stress tolerance. Only changes in superoxide dismutase activity were correlated with plant adaptive responses to salinity. Proline accumulation played no major role in either osmotic adjustment or in the tissue tolerance mechanism. Among other non-enzymatic antioxidants, rutin levels were increased by over 25 fold in quinoa leaves. Exogenous application of rutin to glycophyte bean leaves improved tissue tolerance and reduced detrimental effects of salinity on leaf photochemistry. Electrophysiological experiments revealed that these beneficial effects were attributed to improved potassium retention and increased rate of Na+ pumping from the cell. The lack of correlation between rutin-induced changes in K+ and H+ fluxes suggest that rutin accumulation in the cytosol scavenges hydroxyl radical formed in response to salinity treatment thus preventing K+ leak via one of ROS-activated K+ efflux pathways, rather than controlling K+ flux via voltage-gated K+-permeable channels.

Biochemical changes in Araucaria angustifolia (Araucariaceae) zygotic embryos during the storage

<p>Especies reactivas del oxígeno (ROS) están presentes en todos los organismos aeróbicos, pero los procesos de deterioro de semillas pueden aumentar su producción. El estrés oxidativo causado por el aumento de ROS endógeno puede causar un daño irreparable a las células, que conduce a la pérdida de viabilidad de la semilla. Teniendo en cuenta que la enzima superóxido dismutasa (SOD) compone el primer mecanismo de defensa antioxidante enzimática, este estudio tuvo por objetivo evaluar los embriones cigóticos de semillas recalcitrantes de <em>Araucaria angustifolia</em> durante el almacenamiento los cambios en la actividad de SOD. Además, algunas alteraciones importantes derivadas de estrés oxidativo, como la peroxidación lipídica y los cambios en las proteínas y la integridad del DNA también se evaluaron. Aproximadamente 7 000 semillas fueron cosechadas de una población en el sur de Brasil y almacenadas durante 180 días en el laboratorio (L), refrigeración (R) y congelamiento (F). El análisis de la peroxidación de lípidos a través de los niveles de TBARS, actividad de la SOD, perfil proteico por separación electroforética e integridad del DNA genómico se realizaron a los 0, 60, 120 y 180 días de almacenamiento. Los resultados revelaron un aumento de la peroxidación lipídica y de la actividad de la SOD, especialmente durante el almacenamiento en L, una condición en la que hubo una extensa degradación de las proteínas. Algunas proteínas (45, 32 y 31 kDa) se expresaron sólo en embriones almacenados en condiciones R y F. No se observaron daños en la integridad del DNA nuclear para el período de almacenamiento de semillas en condiciones R y F. Las muestras F mantienen las características bioquímicas analizadas durante todo el período de almacenamiento, con la excepción del perfil de proteínas. Sin embargo, tales cambios son limitantes para el mantenimiento de la viabilidad de la semilla. En conclusión, el almacenamiento en refrigeración puede ser indicado para retrasar las alteraciones metabólicas que se producen cuando las semillas están expuestas a condiciones de ambiente natural después de la cosecha, que extiende el período de conservación de las semillas de <em>A. angustifolia</em>.<strong></strong></p>

Abstract P080: New Strategy, Old Remedy: Elucidating the Effect of Hibiscus Sabdariffa in a Neuronal Model of Oxidative Stress

Introduction: Neurogenic hypertension is characterized by increased blood pressure, neuroinflammation, and neuronal oxidative stress. Thus, its pathophysiology dictates a unique therapeutic strategy. It is established that Hibiscus sabdariffa (HS) plays a beneficial role in decreasing blood pressure, yet the role of HS as an anti-oxidant defense system in neurogenic hypertension has not been investigated. Our objective was to generate an in vitro model of neuronal oxidative stress to test the hypothesis that HS creates a neuroprotective antioxidant defense system. Methods: To create a model of oxidative stress, SY5Y, neuroblastoma cells, were treated with 32uM hydrogen peroxide. To determine the effect of methanol-extracted HSE (50 and 100ug n ≥ 8) in this model of oxidative stress, SY5Y cells were treated with vehicle-PBS, HSE (24hrs), pretreated with HSE (24hrs) and then treated with H2O2 (8hrs). Using molecular techniques markers of oxidative stress were measured and percentages were out of 100. Data was normalized to the control and analyzed by one way ANOVA (p value < .05 was considered significant). Results: HSE significantly increases cell viability (50 or 100ug > 99%) compared to H2O2 alone (43%). HSE significantly decreases ROS generation (113%-50ug versus 89%-100ug) compared to H2O2 (120%). HSE significantly decreases lipid peroxidation (11.3%-50ug versus 10.2%-100ug) compared to H2O2 (135%). HSE significantly increases GSH content (72%-50ug versus 91%-100ug) compared to H2O2 (58%). HSE significantly increases catalase activity (31%-50ug versus 51%,-100ug) compared to H2O2 (23%). HSE significantly increases mitochondrial complex 1 activity (125%-50ug versus 229%-100ug) compared to H2O2 (26.2%). There was no significant change in superoxide dismutase activity amongst groups. Conclusion: These observations suggest that HSE creates an antioxidant defense system that provides cytoprotection against H2O2-induced neuronal oxidative stress. Thus, HS, a known anti-hypertensive should be revisited to investigate its in vivo role in neurogenic hypertension.

Age and sex-related changes in superoxide dismutase activity in bovine tissues

The influence of age, gender, and type of tissue on superoxide dismutase (SOD) activity in bovine organs and tissues was investigated. The investigated material consisted of fragments of tissues and organs (liver, heart, lung, kidney, skeletal muscles, and diaphragm) from healthy cows (n = 15), bulls (n = 15), and female calves (n = 12) collected immediately after slaughter at the slaughterhouse. The total SOD activity was measured in tissue and organ homogenates by spectrophotometric method. PAGE electrophoresis and Western blotting technique with specific anti-SOD antibodies as well as zymography confirmed the presence of enzymatic protein and SOD isoenzymes in examined tissues. The study revealed significant differences in SOD activity between organs and tissues, which might be connected with different metabolic rate. Age-related changes were also observed. SOD activity was twice higher in kidneys, lungs, heart of calves compared to other groups of animals. It was also noticed that SOD activity was higher in younger animals and decreased with ageing among the group of bulls. Gender-related differences were observed in lungs and diaphragm. It was concluded that SOD activity depends on sex steroids, which is reflected in age and gender discrepancies, as well as metabolic rate of tissues.

Response of biochemical biomarkers in the aquatic crustacean Daphnia magna exposed to silver nanoparticles.

The proliferation of silver nanoparticle (AgNP) production and use owing to their antimicrobial properties justifies the need to examine the resulting environmental impacts. The discharge of biocidal nanoparticles to water bodies may pose a threat to aquatic species. This study evaluated the effects of citrate-coated AgNPs on the standardized test organism Daphnia magna Straus clone MBP996 by means of biochemical biomarker response. AgNP toxicity was compared against the toxic effect of Ag(+). The toxicity endpoints were calculated based upon measured Ag concentrations in exposure media. For AgNPs, the NOAEC and LOAEC values at 48 h were 5 and 7 μg Ag/L, respectively, while these values were 0.5 and 1 μg Ag/L, respectively, for Ag(+). The EC50 at 48 h was computed to be 12.4 ± 0.6 and 2.6 ± 0.1 μg Ag/L for AgNPs and Ag(+), respectively, with 95 % confidence intervals of 12.1-12.8 and 2.3-2.8 μg Ag/L, respectively. These results indicate significant less toxicity of AgNP compared to free Ag(+) ions. Five biomarkers were evaluated in Daphnia magna neonates after acute exposure to Ag(+) or AgNPs, including glutathione (GSH) level, reactive oxygen species (ROS) content, and catalase (CAT), acetylcholinesterase (AChE), and superoxide dismutase (SOD) activity. AgNPs induced toxicity and oxidative stress responses in D. magna neonates at tenfold higher concentrations than Ag. Biochemical methods revealed a clear increase in AChE activity, decreased ROS level, increased GSH level and CAT activity, but no significant changes in SOD activity. As Ag(+) may dissolve from AgNPs, these two types of Ag could act synergistically and produce a greater toxic response. The observed remarkably high toxicity of AgNPs (in the parts-per-billion range) to crustaceans indicates that these organisms are a vulnerable link in the aquatic food chain with regard to contamination by nanosilver. Graphical Abstract ᅟ.

Molecular mechanism of copper-zinc superoxide dismutase activity change exposed to N-acetyl-L-cysteine-capped CdTe quantum dots-induced oxidative damage in mouse primary hepatocytes and nephrocytes.

Quantum dots (QDs) are engineered semiconductor nanocrystals with promising application in biomedicine, which have potential toxic effect on biomacromolecules by direct interaction and indirect impact in the body. In this work, the effect of N-acetyl-L-cysteine-capped CdTe quantum dots with fluorescence emission peak at 612nm (QDs-612) on copper-zinc superoxide dismutase (Cu/ZnSOD) at molecular and cellular level was investigated using isothermal titration calorimetry, spectroscopic techniques, cell counting kit-8, and total SOD assay. The hydrophobic interaction between Cu/ZnSOD and QDs-612 caused static fluorescence quenching of the protein, which was spontaneous with binding constant calculated to be 3.28 × 10(5)Lmol(-1). The microenvironment of tyrosine residues, skeleton, and secondary structure of Cu/ZnSOD were changed with adding QDs-612. The molecular Cu/ZnSOD activity was inhibited at different concentrations of QDs-612 as well as the intracellular Cu/ZnSOD activity after 2-h exposure. Compared with the cell viability of hepatocytes and nephrocytes (decreased markedly of the initial level) with higher concentrations of QDs-612 in the absence of vitamin C, the cell viability of these two primary cells increased in the presence of vitamin C, indicating the oxidative damage induced by QDs-612. Therefore, the inhibition of Cu/ZnSOD activity in these two primary cells may be caused by the oxidative damage of massive ROS or direct interaction with QDs-612. This work establishes a new approach to investigate the biological toxicity of CdTe QDs to biomacromolecule from both molecular and cellular perspectives and obtains experimental evidence to thoroughly study the toxicity of CdTe QDs in vivo.

Aspects of resilience of polar sea ice algae to changes in their environment

Sea ice algae are primary producers of the ice-covered oceans in both polar regions. Changes in sea ice distribution are potentially altering exposure to photosynthetically active radiation (PAR) and ultraviolet-B (UV-B) wavelengths of light. Incubations using monospecific cultures of common species from the Ross Sea, Antarctic Peninsula and Arctic Ocean were carried out at ecologically relevant light levels during periods of 7 days to examine tolerance to conditions likely to be faced during sea ice thinning and melt. Algal responses were assessed using chlorophyll fluorescence techniques and superoxide dismutase (SOD) activity. Quantum yields of cultures incubated in the dark and at ambient light did not differ. At higher light levels, the Ross Sea and Arctic cultures showed no significant change in photosynthetic health. Cultures from the Antarctic Peninsula showed a significant decrease. Antarctic cultures showed no detectable changes in SOD activity. Arctic culture showed dynamic changes, initially increasing, then decreasing to the end of the study. The general lack of significant changes signals the need for further parameters to be assessed during such experiments. The coupling between measured parameters appeared to protect photosynthetic health, even though significant effects have been detected in other studies when subjected to PAR or UV-B alone.

Antioxidative responses to short term waterlogging stress in pigeon pea

Waterlogging stress is a major abiotic stress having detrimental effects on crop production. Pigeon pea (Cajanus cajan (L.) Millsp.) is a waterlogging sensitive legume crop. Effect of short term waterlogging stress was studied on the activity of antioxidant enzymes in two pigeon pea genotypes, viz., ICPL-84023 (waterlogging resistant) and MAL-18 (waterlogging susceptible). The objective of the present experiment was to study the changes in antioxidant enzyme system in response to waterlogging. Waterlogging stress was imposed for 12 h at early vegetative stage (20 days after sowing), and activities of superoxide dismutase, ascorbate peroxidase, catalase, peroxidase and polyphenol oxidase were recorded in the root tissues at 0, 3, 6, 9 and 12 h after imposing waterlogging stress. Enzyme activities were higher in ICPL-84023 as compared to MAL-18. Activities of peroxidase and polyphenol oxidase increased immediately (3 h) after imposing waterlogging stress, indicating the activation of antioxidant enzyme system at very early stages. Changes in superoxide dismutase activity were variable at different stages of observation. Catalase activity increased significantly at 9 h and then decreased. Ascorbate peroxidase activities did not change significantly under waterlogging.

Mitigation of Systemic Oxidative Stress by Curcuminoids in Osteoarthritis: Results of a Randomized Controlled Trial

ABSTRACTOxidative stress is implicated in the pathogenesis of osteoarthritis. Curcuminoids are natural polyphenols with strong antioxidant capacity and may thus be helpful in the treatment of osteoarthritis. The present randomized double-blind placebo-controlled trial investigated the efficacy of curcuminoids in reducing systemic oxidative burden in patients suffering from knee osteoarthritis. Forty patients with mild-to-moderate primary knee osteoarthritis were given curcuminoid capsules (1500 mg/day in 3 divided doses; n = 19) or matched placebo capsules (n = 21) for a period of 6 weeks. Curcuminoids were co-administered with piperine (15 mg/day) in order to improve the bioavailability. Serum activities of superoxide dismutase (SOD) and concentrations of reduced glutathione (GSH) and malonedialdehyde (MDA) were determined spectrophotometrically at baseline and at the end of the treatment period in both groups. Serum activities of SOD as well as GSH and MDA concentrations were comparable between the study groups at baseline (p > 0.05). There was a significant elevation in serum SOD activities (mean change: 2.94 ± 3.73 vs. −0.38 ± 1.33; p < 0.001), a borderline significant elevation in GSH concentrations (mean change: 1.39 ± 2.78 vs. −0.02 ± 1.62; p = 0.064) and a significant reduction in MDA concentrations (mean change: −5.26 ± 4.46 vs. −2.49 ± 3.81; p = 0.044) in the curcuminoids compared with the placebo group. Changes in serum activities of SOD and concentrations of GSH and MDA during the course of trial were significantly correlated. Short-term supplementation with curcuminoids attenuates systemic oxidative stress in patients with osteoarthritis. These antioxidant effects may account for the reported therapeutic effects of curcuminoids in relieving osteoarthritis symptoms.

Effect of zinc supplementation on superoxide dismutase activity in patients with ulcerative rectocolitis.

Ulcerative rectocolitis is characterized by diffuse mucosal inflammation and oxidative stress. Thus, the organism activates the antioxidant defence system in an attempt to reduce the excessive production of reactive oxygen species or neutralize them. This study evaluated the effect of zinc supplementation on the activity of the enzyme superoxide dismutase (SOD) in patients with ulcerative rectocolitis. The study included 24 patients, aged between 20 and 59 years and diagnosed with ulcerative rectocolitis, in the remission stage of the disease, who were divided into two groups: experimental - deficient in zinc (n=12) and control - normal or high zinc (n=12). Only the first group underwent supplement intervention, in the form of zinc gluconate (30 mg Zn/day), taken daily in the morning, fasted for 60 days. Plasma and erythrocyte zinc concentrations were determined by flame atomic absorption spectrophotometer. The erythrocyte SOD activity was determined in vitro according to the methodology recommended by the manufacturer Randox. Zinc supplementation caused a significant increase in the plasma concentrations of the mineral, and showed a significant reduction in erythrocyte zinc, remaining within normal limits. The SOD activity was high in patients of both the experimental and control groups, with no difference after supplementation. This study demonstrates that zinc supplementation improves the homeostatic condition of the mineral, with no change in SOD activity, as a marker of oxidative stress in patients with ulcerative rectocolitis.

Cylindrospermopsin induces oxidative stress and genotoxic effects in the fish CLC cell line.

Cylindrospermopsin (CYN) is a cyanotoxin detected in water reservoirs worldwide. The toxin is a potent protein synthesis inhibitor capable of adversely influencing a wide range of cell functions. While data on the prooxidative potency of CYN are inconsistent, genotoxic effects towards certain mammalian cell types have been described. However, such a potential on fish cells has not yet been investigated. Hence, the aim of the study was to elucidate the prooxidative and genotoxic impact of CYN on a common carp (Cyprinus carpio L.) leucocyte cell line (CLC). The cells were incubated with the cyanotoxin at concentrations of 0.1, 0.5 or 1 µg ml⁻¹. After 24 h, cytotoxic activity of CYN at the highest used concentration was confirmed by decreased cell membrane integrity and inhibited cell proliferation. Additionally, CYN at 0.5 and 1 µg ml⁻¹ increased intracellular ATP levels and decreased the reduced to oxidized glutathione ratio. Furthermore, a significant increase in the reactive oxygen species (ROS) production with concomitant changes in superoxide dismutase activity was observed after a 3.5-h exposure of the cells to the toxin. Genotoxic activity of CYN, manifested as oxidative DNA damage and elevated number of micronuclei, was also detected in exposed cells. The obtained results indicate that CYN is able to exert a wide range of adverse effects, including oxidative stress and genotoxicity in fish leucocytes.

Changes in the activity of superoxide dismutase isoforms in the course of low-temperature adaptation in potato plants of wild type and transformed with Δ12-acyl-lipid desaturase gene

We investigated the changes in the total activity of superoxide dismutase (SOD) and the role of its isoforms in hardening potato (Solanum tuberosum L., cv. Desnitsa) plants of wild type and transformed with desA gene of Δ12-acyl-lipid desaturase from Synechocystis sp. PCC 6803. Hydroponically grown 8-week-old plants were exposed for six days to hardening temperature of 5°C. Before chilling, the total SOD activity in the transformed plants was somewhat greater than in the control plants. By the first day of hardening, SOD activity in both potato genotypes rose almost 1.5 times; however, the absolute value of SOD activity was considerably greater in the transformed plants. Subsequently, the total SOD activity in both genotypes decreased and by the end of the 6th day, it almost returned to the initial level. Electrophoretic and inhibitor analyses of potato plants revealed three types of SOD with one isoform of Mn-SOD, four isoforms of Fe-SOD, and two isoforms of Cu/Zn-SOD. In both genotypes, Fe-SOD3 manifested the greatest activity before chilling and in the course of hardening. Such changes in SOD activity corresponded to the rate of generation of superoxide anion radical and elevation of the content of products of peroxide oxidation of lipids (POL). Our data suggest that in the course of hardening of cold-resistant potato plants, the total SOD activity changed mostly due to Fe-SOD3 and to some extent as a result of elevated Cu/Zn-SOD2 activity, which was particularly evident at the beginning of hardening and more pronounced in the transformed plants. We assume that such temporal pattern is related to a greater rate of superoxide anion generation in the transformed plants as compared with control plants.

Protective Effect of Resveratrol on Biomarkers of Oxidative Stress Induced by Iron/Ascorbate in Mouse Spermatozoa

Resveratrol (RVT) is a polyphenolic compound found mainly in the grape and attributed with various pharmacological properties, among them their antioxidant activity. In the present study, we assess the antioxidant activity of resveratrol on oxidative damage induced by ferrous iron/ascorbate (100 µM/150 µM) in sperm of CD1+ mice. We evaluated several parameters in spermatozoa treated with or without resveratrol: (i) sperm quality analysis; (ii) mitochondrial transmembrane potential (Δψm); (iii) ROS generation; (iv) superoxide dismutase (SOD) activity; (v) glutathione peroxidase (GPX) activity; (vi) lipid peroxidation; (vii) and in vitro fertilization (IVF) capability. Spermatozoa treated with RVT (15 µg/mL) before ferrous iron/ascorbate treatment exhibited: a significant increase in motility (8-fold), a significant increase in viability (2-fold), a significant increase in Δψm (1.15-fold), accompanied with a significant decrease in the generation of ROS (4.96-fold), a significant decrease in GPX activity (1.32-fold), and a significant decrease in lipid peroxidation concentration (10.29-fold) relative to spermatozoa treated with ferrous iron/ascorbate; however, no changes in SOD activity were observed. Finally, spermatozoa treated with RVT before ferrous iron/ascorbate treatment showed a significant increase in oocyte fertilization (1.2-fold), relative to spermatozoa treated with ferrous iron/ascorbate. These results suggest that RVT possesses antioxidant properties that may prevent the deleterious effects produced by oxidative damage on spermatozoa, resulting in the maintenance of fertility.