Oxidative stress and genotoxicity of 1-methyl-3-octylimidazolium chloride on loach (Misgurnus anguillicaudatus)

This study was a preliminary step to evaluate the acute toxicity of 1-methyl-3-octylimidazolium chloride ([C₈mim]Cl) on loach (Misgurnus anguillicaudatus) by determining the effects on hepatic antioxidant enzyme activities and by the comet assay. The results showed that [C₈mim]Cl had acute toxicity at concentrations above 20 mg L^?1, inducing oxidative stress and genotoxicity on fish liver cells. In respect to enzyme activities, [C₈mim]Cl induced changes in the activities of superoxide dismutase, catalase, and glutathione content the livers of fish exposed at 20–80 mg L^?1. [C₈mim]Cl at the same exposure level caused a remarkable increase in malondialdehyde level. The comet assay indicated that [C₈mim]Cl at 20–80 mg L^?1 induced genotoxicity in liver cells. With increased exposure concentration and time, the two comet parameters trailing rate and tail moment were significantly increased, with significant differences (P < 0.05) observed between control group and each treatment group. The present study shows that ionic liquids can be a threat to the health of aquatic organism when accidentally released to aquatic ecosystems.     

Effect of latex material on antioxidant enzymes,lipid peroxidation,DNA damage,and chromosomal aberration

Cell integrity is affected by oxidative stress when the production of active oxidants overwhelms antioxidant defense mechanisms. Latex, a natural polymer obtained from Hevea brasiliensis, is used in medical industry for manufacturing surgical gloves, urinary catheters, and dental dams. The aim of this study was to evaluate the effects of latex material on oxidative stress by in vivo and in vitro methods. In addition, the material was screened for its ability to induce any chromosomal aberrations (CAs) by in vitro method. In vivo studies were carried out with implanted latex material onto subcutaneous tissue of various batches of experimental Wistar rats. At the end of experimental period, animals were anesthetized, blood was collected for serum analysis, and sacrificed. Liver was excised for the determination of antioxidant enzymes and lipid peroxidation (LPO). Subcutaneous tissues were obtained for the extraction of genomic DNA from implanted animals and checked for the presence of 8-hydroxy-2-deoxyguanosine (8-OHdG), considered an indicator of DNA damage. Simultaneously, in vitro studies were carried out using fresh liver and subcutaneous tissue obtained from Swiss albino mice treated with physiological saline extract of latex material. For the estimation of both in vitro and in vivo oxidative stress, 10% liver homogenate was assessed for stress indicators like reduced glutathione, glutathione reductase, glutathione peroxidase, LPO and protein content. The results of both in vivo and in vitro studies indicated that the chemical leachents from the latex material did not significantly affect LPO and the levels of antioxidant enzymes. There was also no significant increase in 8-OHdG content due to the presence of implanted latex material. Finally, the results of in vitro CA test and G banding indicated that extracts of test material did not induce any chromosomal abnormalities.     

Antioxidant responses in the polychaete Perinereis gualpensis (Nereididae) exposed to the carbon nanomaterial fullerene (C60)

The objective of this study was to analyse biochemical responses induced by the carbon nanomaterial fullerene (C₆₀) in the polychaete Perinereis gualpensis (Nereididae). The activity of glutathione-S-transferase (GST), glutathione reductase (GR) and glutamate cysteine ligase (GCL), as well as total antioxidant capacity, concentration of glutathione (GSH) and malondialdehyde (TBARS), were analysed. Estuarine worms were maintained in sediments collected at an unpolluted site and spiked with fullerene (3 mg C₆₀·g^?1 sediment). A control group was run in parallel. Scanning electron microscope (SEM) images of sediment and fullerene indicated that the size of the carbon nanomaterial should enable it to be ingested by the polychaete. No evidence of oxidative damage (TBARS) was observed in any of the treatments, and the same was true for GSH and GCL measurements (p>0.05). Total antioxidant capacity was higher in the C₆₀ group after 2 and 7 d when compared with the control group (p<0.05), suggesting that fullerene is acting as an antioxidant. The fact that P. gualpensis is an infaunal organism diminishes the chance of fullerene photoexcitation with consequent reactive oxygen species production. Thus, the data indicated an absence of toxic responses mediated by oxidative stress in estuarine worms exposed to C₆₀ mixed in sediments.     

Effects of subchronic exposure to carbofuran on antioxidant defence system and malondialdehyde levels in common carp (Cyprinus carpio L.)

The present study focused on the assessment of oxidative stress induction by pesticides such as carbamates which are widely used as insecticides and nematicides and contaminate aquatic ecosystems on certain biomarkers in liver of common carp (Cyprinus carpio L.). Biomarkers selected for stress monitoring were malondialdehyde (MDA), an index of lipid peroxidation, and antioxidant defence system enzymes, mainly catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) activities in liver of fish exposed to 0, 10, 50, or 100?µg?L^?1 of carbofuran for 4, 15, or 30 days. Oxidative stress was found in liver of common carp exposed to carbofuran which was manifested by a decrease in CAT and GR activities after 4 and 30 days of exposure. An adaptive response was probably produced since at day 15 no modifications in the CAT activity and increased GR activity were observed. In addition, a decrease in MDA content with the highest concentration of carbofuran used was found after 30 days of exposure. However, no significant changes were found in GST activity showing a varied response. The results concerning oxidative and antioxidant profiles indicate that subchronic exposure to the insecticide carbofuran is capable of inducing oxidative stress in fish.     

Effects of paclobutrazol (PP333) on lead and zinc accumulations in Pseudostellaria maximowicziana

Paclobutrazol (PP333) can enhance the resistance capabilities of plants to stress conditions. In this study, PP333 were sprayed on the lead (Pb) and zinc (Zn) accumulator plant Pseudostellaria maximowicziana, which was planted in Pb–Zn contaminated soil, and the effects of PP333 on Pb and Zn accumulation levels in P. maximowicziana were studied. Spraying 10?mg/L PP333 increased, while 20, 30 and 50?mg/L PP333 decreased, the biomass of P. maximowicziana compared with the control. The 10?mg/L PP333 had no significant effects on the photosynthetic pigment contents of P. maximowicziana compared with the control, while the other doses increased the contents. The activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase) and the Pb and Zn concentrations in P. maximowicziana were increased by PP333 compared with the control. These items had the increase trend with the increase of PP333 concentrations. Only 10 and 20?mg/L PP333 increased the amount of Pb extracted by P. maximowicziana shoots, while all of the doses increased the amount of Zn extracted by P. maximowicziana shoots. Thus, low concentration of PP333 could promote the growth and heavy metal extraction ability of P. maximowicziana shoots, with the 10?mg/L being the best.     

Genotoxicity in the freshwater gastropod Lymnaea luteola L: assessment of cell type sensitivities to lead nitrate

The aquatic ecosystems are converting into the highly contaminated site due to environmental pollutants. The present study explores the oxidative stress and toxic potential of lead nitrate in freshwater snail Lymnaea luteola (L. luteola) L. The snails were exposed to an environmentally relevant concentration of lead nitrate for 24 and 96?h. Later exposure to lead nitrate (0, 10, 20 and 40?µg/mL) to the freshwater snail, the level of reactive oxygen species, malondialdehyde and nitric oxide (NO) were increased and glutathione, glutathione-S-transferase were decreased. Lead-nitrate-induced haemocyte cell death and it was observed by using Annexin-V FITC/PI through a flow cytometer. DNA damage in haemocyte cells was measured at above doses of lead-nitrate exposure for 24 and 96?h and it was compared to the untreated snail. Average tail DNA (%) and olive tail moment in single-cell gel test were increased dose and duration fashion and maximum DNA damage was measured at 96?h. These results indicate the potential toxicity and genotoxicity of lead nitrate in acute treatment to L. luteola and single-cell gel test are the assay for rapid detection of genetic effects.     

The effects of evening primrose oil on arsenic-induced oxidative stress in rats

Forty-eight male Wistar albino rats were allocated to the four groups such that each comprised 12 animals. The first group was maintained as the control. In group 2, evening primrose oil was administered at a dose of 0.1 mL rat^?1 day^?1 (～500 mg kg^?1 bw) into the stomach via gavage, whilst in group 3 sodium arsenide was administered at a concentration of 100 mg L^?1 in ad-libitum drinking water for 30 days. The fourth group was given 0.1 mL rat^?1 day^?1 evening primrose oil into the stomach via gavage plus 100 mg L^?1 of sodium arsenide in ad-libitum drinking water for 30 days. At the end of the 30th day, tissue (liver, lung, kidney, brain, heart, spleen, and testis) and blood samples were collected from each group. Malondialdehyde (MDA) and nitric oxide (NO) levels and superoxide dismutase, catalase and glutathione peroxidase activities were measured in the samples. Exposure to arsenic in rats causes oxidative stress by increasing lipid peroxidation (increase of MDA and NO levels) and altering the activity of antioxidant enzymes. Evening primrose oil did not have any adverse effects. Furthermore, it was ascertained that the administration of arsenic with evening primrose oil reduced the severity of oxidative stress.     

Antioxidant enzymatic activities and lipid peroxidation in liver and ovary of zebrafish (Danio rerio) exposed to deltamethrin

Deltamethrin (DM) is being used as a substitute for organochlorines and organophosphates in pest control because of its low environmental persistence and toxicity. But it has become an environmental contaminant as it has been used widely. In this study, we investigated the effect of DM (technical grade) on the antioxidant system of adult zebrafish. For this, six-month-old fish were exposed to 2, 4 and 6?μg/L of DM for 96?h. The tissues selected were liver and ovary. Our data showed that exposure to DM increases CAT (catalase), SOD (superoxide dismutase), GPx (glutathione peroxidase, antioxidant enzymes), LPO (lipid peroxidation, non-enzymatic antioxidant) and GST (glutathione S-transferase, detoxifying enzyme) in liver and ovary. Increased GST could detoxify the toxicant; still there could be enough DM to cause oxidative stress. It appears from our study that zebrafish used compensatory mechanisms in eliminating reactive oxygen species. These data will be useful as oxidative stress is being used as a biomarker for aquatic pollution.     

The role of thymoquinone as antioxidant protection on oxidative stress induced by imidacloprid in male and female Swiss albino mice

The aim of the present study was to evaluate the possible protective effects of thymoquinone (TQ), an antioxidant agent, against imidacloprid (IMI)-induced oxidative stress in male and female mice. In total, 48 Swiss Albino male and female mice were fed a standard rodent diet and divided into 3 equal groups: the animals in the control group (vehicle treated) were given corn oil, the second group were orally administered 15 mg/kg/day IMI alone, and the third group were orally administered 15 mg/kg/day IMI and with TQ at 10 mg/kg/day for 21 days. During the experimental period, there were no significant changes between initial body weights and final body weights of IMI treated male and female mice. IMI produced significant increase in blood, liver, kidney, and heart malondialdehyde (MDA) levels and decrease in blood and liver glutathione (GSH) levels. In addition, IMI treatment decreased erythrocyte, liver, and kidney superoxide dismutase (SOD) activity in male mice and decreased erythrocyte and liver SOD activity in female mice. Erythrocyte catalase (CAT) activities were found to be low in male and female mice. However, treatment with TQ reversed IMI-induced oxidative stress, lipid peroxidation, and activities of antioxidant enzymes. Moreover, TQ exhibited protective action against the IMI-induced histopathological changes in tissues of male and female mice. In conclusion, TQ was found to be effective in protecting mice against IMI-induced oxidative stress by enhancing antioxidant defense mechanisms.     

双酚A对小鼠肝脏和肾脏细胞的氧化损伤

为探究双酚A(BPA)的氧化毒性,分别以剂量为20、40和80mg·kg~(-1)·d~(-1)的BPA对雄性昆明小鼠灌胃处理1周,并测定了小鼠体内活性氧自由基(ROS)水平、还原型谷胱甘肽(GSH)含量、丙二醛(MDA)含量和DNA-蛋白质交联系数(DPC)。与对照组相比,各BPA暴露组小鼠肝脏和肾脏细胞中的ROS生成量、MDA含量和DPC系数均升高,而GSH含量下降(P<0.05或P<0.01)。ROS生成量、GSH含量和DPC系数均显示出剂量-效应关系。研究表明,BPA可扰乱小鼠肝脏和肾脏细胞的氧化应激平衡,诱导细胞氧化损伤。     

Microwave-assisted synthesized zinc nanoparticles attenuate cisplatin-induced testicular toxicity in mice

Abstract

The purpose of this study was to investigate the protective effects of zinc nanoparticles against cisplatin-induced testicular toxicity in mice. Zinc nanoparticles were produced by microwave-assisted synthesis using Lavandula vera extract as reducing agent. Single doses of cisplatin (7?mg/kg, intraperitoneally) and ZnSO₄ (10?mg/kg, orally), and various doses of zinc nanoparticles (10???50?mg/kg, orally) and vitamin E (100?mg/kg, interaperitoneally) were administered. The protective role of zinc nanoparticles was determined biochemically and histologically. Gradual reduction in malondialdehyde levels and elevation in glutathione levels and in the activities of superoxide dismutase and catalase upon administration of zinc nanoparticles were observed. The pathology of mice treated with cisplatin/vitamin E and cisplatin/zinc nanoparticles were apparently equal, but vitamin E treatment was more effective in lowering oxidative stress markers than zinc nanoparticles. These findings suggest that co-administration of zinc nanoparticles with cisplatin could prevent adverse effects on the male reproductive system via their potential antioxidant properties.     

Tualang honey supplementation improves oxidative stress status among chronic smokers

Free radicals induced by cigarette smoking have been linked to an increase in oxidative stress resulting in smoking-related cardiovascular diseases. However, the possible effect of honey that has antioxidant property in improving oxidative stress status among smokers has not yet been reported. Hence, this study was to determine the effects of 12-week Tualang honey supplementation on F₂-isoprostanes, superoxide dismutase, glutathione peroxidase, catalase, and total antioxidant status among chronic smokers. A total of 32 non-smokers and 64 chronic smokers were recruited from Quit Smoking Clinic and Health Campus, Universiti Sains, Malaysia. Smokers were randomized into two groups (n = 32/group) namely smokers without supplementation and smokers with honey supplementation (20 g/day) for 12 weeks. Blood was obtained from non-smokers and smokers at pre-intervention and from smokers at post-intervention. During pre-intervention, the levels/activity of F₂-isoprostanes, total antioxidant status, and catalase were significantly higher while superoxide dismutase and glutathione peroxidase were lower in smokers than non-smokers. During post-intervention, in supplemented smokers, there were significant decrease in F₂-isoprostanes and increase in total antioxidant status, glutathione peroxidase and catalase levels/activities compared with pre-intervention. This study indicates that honey supplementation improves oxidative stress status suggesting a beneficial role of honey in reducing the risk of cardiovascular diseases.     

Tissue-specific stress and hepatic DNA damage in Pelteobagrus fulvidraco caused by low concentrations of cadmium

Physiological stress and DNA damage in Pelteobagrus fulvidraco induced by continuous exposure to cadmium at concentrations of 170 and 1700 µg/L for up to 28 days was evaluated. The activities of acetylcholinesterase and monoamine oxidase in brain tissue, Na⁺-K⁺-ATPase and glutathione in gill tissue, and superoxide dismutase and catalase in liver tissue were measured. In studying random amplified polymorphic DNA to evaluate cadmium-induced hepatic genotoxicity, both the appearance of new bands and the disappearance of existing bands were observed, as well as increased levels of monoamine oxidase and Na⁺-K⁺-ATPase and decreased activities of antioxidant enzymes. The results suggest that continuous exposure to cadmium at the studied levels can induce biochemical and physiological changes and DNA damage in P. fulvidraco.     

Dichloroacetate- and trichloroacetate-induced modulation of superoxide dismutase,catalase, and glutathione peroxidase activities and glutathione level in the livers of mice after subacute and subchronic exposures

Dichloroacetate (DCA) and trichloroacetate (TCA) were previously found to induce various levels of oxidative stress in the hepatic tissues of mice after subacute and subchronic exposures. The cells are known to have several protective mechanisms against production of oxidative stress by different xenobiotics. To assess the roles of the antioxidant enzymes and glutathione (GSH) in DCA- and TCA-induced oxidative stress, groups of B6C3F1 mice were administered either DCA or TCA at doses of 7.7, 77, 154, and 410 mg kg^?1 day^?1, by gavage for 4 weeks (4-W) and 13 weeks (13-W), and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities, as well as GSH were determined in the hepatic tissues. DCA at doses ranging between 7.7–410, and 7.7–77 mg kg^?1 day^?1, given for 4-W and 13-W, respectively, resulted in either suppression or no change in SOD, CAT, and GSH-Px activities, but doses of 154–410 mg DCA kg^?1 day^?1 administered for 13-W were found to result in a significant induction of the three enzyme activities. TCA administration on the other hand, resulted in increases in the SOD and CAT activities, but caused suppression of GSH-Px activity in both the periods. Except for the DCA doses of 77–154 mg kg^?1 day^?1 administered for 13-W that resulted in a significant reduction in the GSH levels, all other DCA as well as TCA treatments produced no changes in GSH. Since these enzymes are involved in the detoxification of the reactive oxygen species (ROS), superoxide anion (SA), and H₂O₂, it is concluded that SA is the main contributor to DCA-induced oxidative stress, while both ROS contribute to that of TCA. The increase in the enzyme activities associated with 154–410 mg DCA kg^1? day^?1 in the 13-W period suggest their role as protective mechanisms contributing to the survival of cells modified in response to those treatments.     

Oxidative stress mediated cytotoxicity of TiO2 nano anatase in liver and kidney of Wistar rat

This study examined the adverse effects of TiO₂ nanoparticle (nano-TiO₂) on the kidney and liver of Wistar rats. Changes of serum biochemical parameters and pathological lesions indicated that liver and kidney were significantly affected in animals treated with 50?mg?kg^?1 of nano-TiO₂. The inverse relationship between the level of reactive oxygen species and the activities of superoxide dismutase, catalase, and glutathione peroxidase indicates that nano-TiO₂ induces oxidative stress. A significant increase in the apoptosis of liver and kidney in a dose-dependent manner was also observed. The ultrastructural observations confirmed the internalization of nano-TiO₂ and their direct involvement in the mitochondria-mediated cytotoxicity. Data indicated that nano-TiO₂ induce oxidative stress which produces genotoxicity such as oxidative DNA damage, micronuclei (MN) induction, and cell apoptosis in liver and kidney.     

Screening of endogenous antioxidants in some medicinal plants

The evaluation of antioxidant enzymes and antioxidant metabolites was done in leaf tissues of Azadirachta indica, Butea monosperma, Cassia fistula, Mangifera indica, and Syzygium cumini growing in the Thar Desert, Rajasthan, India. The plants are naturally exposed to drought stress and high temperatures during summer. Enzymatic reactive oxygen species (ROS) scavenging mechanisms in plants include superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase, catalase, and guaiacol peroxidase, and non-enzymatic antioxidants including the carotenoids, proline, and vitamin C were studied. The strategies to cope up with ROS under these extreme conditions are plant-specific. The highest activity of APX was found in M. indica (13.6?±?2.4?units?g^?1 fresh wt.). A. indica exhibited maximum guaiacol peroxidase activity (0.024?±?0.006?units?min?g^?1 fresh wt.), while S. cumini showed maximum SOD (12.5?±?2.3?units?g^?1 fresh wt.) and catalase activities (6.9?±?2.2?units?g^?1 fresh wt.). M. indica and S. cumini have been found to be more potent antioxidant systems among the studied plants.     

GO通过氧化损伤激活秀丽线虫未折叠蛋白反应

以秀丽线虫为受试生物,探讨氧化石墨烯(GO)对秀丽线虫未折叠蛋白应答的激活及其与氧化应激的关系。将L4幼虫暴露于GO中24 h,通过检测活性氧(ROS)水平、乳酸脱氢酶(LDH)、丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)等指标评估GO对秀丽线虫所致氧化损伤;以hsp-4和hsp-6分别作为秀丽线虫内质网和线粒体未折叠蛋白反应(UPR)的报告基因评价GO对秀丽线虫UPR应答的激活;同时以谷胱甘肽(GSH)作为抗氧化剂探讨GO所致UPR应答与氧化应激的关系。研究结果显示,GO暴露后秀丽线虫体内ROS、LDH和MDA水平升高,抗氧化酶活性上升;内质网和线粒体UPR反应增强,GSH预处理可以降低内质网和线粒体UPR应答。研究表明,GO短期暴露可以诱导秀丽线虫机体氧化应激进而激活UPR应答,抗氧化保护可以降低UPR应答反应。     

Assessment of the in vivo genotoxicity of a new formulation of Bacillus thuringiensis var israelensis SH-14

Biological control agents have become a useful alternative for the reduction of the use of chemical insecticides. LABIOFAM (Cuba) is developing a new formulation of a biolarvicide that possesses as active biological agent Bacillus thuringiensis var israelensis serotype H14. In order to evaluate the genotoxicity of this new formulation, an in vivo battery test was used: micronucleus (MN), chromosome aberrations (CAs), and sperm morphology (SM) assays. A dose of 6.45?×?10⁸ spores was administered per animal via oral administration. Bone marrow cells were collected 24?h after a two day treatment for the MN assay, and 24?h after a unique treatment for the CA assay, using cyclophosphamide as the positive control. Sperm cells were collected at 5 weeks from the first of five administrations for the SM test, using acrylamide as positive control. Bacillus thuringiensis var israelensis serotype H14 failed to show either a significative increase of micronucleated polychromatic erythrocytes, chromosomal aberrations, or sperm abnormalities. Acute oral administration of a high dose of Bacillus thuringiensis var israelensis serotype H14 did not produce mutagenic effects in bone marrow or sperm cells.     

Effects of benzo(k)fluoranthene,a polycyclic aromatic hydrocarbon on DNA damage,lipid peroxidation and oxidative stress in marine gastropod Morula granulata

Benzo(k)fluoranthene [B(k)F] is one of the widespread priority pollutants of polycyclic aromatic hydrocarbons that has been scarcely studied for exposure assessment. With studies reporting a high amount B(k)F in sediments and water samples around the world, it has become vital to study its effects on aquatic organisms. In this connection, this study is conducted to study the effect of different concentrations of B(k)F (1, 10, 25 and 50?µg/L) in marine gastropod Morula granulata exposed in vivo for 96?h. A concentration-dependent increase in percentage tail DNA (TDNA) as measured by comet assay was observed in snails exposed to B(k)F. Exposure concentrations above 1?µg/L B(k)F showed significant increase in superoxide dismutase (SOD) activity and lipid peroxidation value in snails. After 96?h, SOD activity was found to be doubled for 50?µg/L B(k)F in comparison to control. A significant increase in catalase and glutathione S-transferase activity was observed at all exposure conditions at the end of the exposure time. Our study showed that B(k)F induces oxidative stress in snails which further lead to genotoxic damage. To our knowledge, this is the first study on oxidative stress and genotoxic damage in gastropods exposed to B(k)F.     

Protective role of epigallocatechin 3-gallate against lead-induced toxicity in human neuroblastoma cells

Lead (Pb) is a heavy metal, known to induce oxidative stress and produce damage to the antioxidant defence system ultimately leading to cell death. Antioxidants such as epigallocatechin 3-gallate (EGCG), a green tea polyphenol, was shown to play a protective role during Pb-exposure. In this study, human SH-SY5Y neuroblastoma cells were exposed to different concentrations (0.01–10?µM) of Pb for 48?h to determine effects on the viability of cells. It was observed that IC₅₀ was at 5?µM and at this concentration the cells exhibited a significant increase in caspase-3 activity, an indicator of apoptosis at least by 10-fold and the decrease of 59.4% in glutathione (GSH) content. The total cellular prostaglandin-E₂ (PGE₂) level was found to be elevated at least 10-fold upon Pb exposure. However, the effects of Pb on cells pre-incubated with 50?µM EGCG followed by 5?µM Pb showed 40% inhibition in cell viability, 17.3% decrease in caspase-3 activity, 23% increase in GSH content, and 11.4% fall in PGE₂ levels when compared with cells exposed to Pb only. Data suggest that EGCG exerted a significant protection to cell viability in preventing cell death and elevation in levels of GSH in cells exposed to Pb. However, EGCG did not elicit any significant effect on release of PGE₂ indicating the nature of EGCG as an effective anti-apoptotic, antioxidant, and anti-inflammatory agent.