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Age-related macular degeneration (AMD) is a chronic disease that usually develops in older people. Pathogenetic changes in this disease include anatomical and functional complexes. Harmful factors damage the retina and macula. These changes may lead to partial or total loss of vision. The disease can occur in two clinical forms: dry (the progression is slow and gentle) and exudative (wet—progression is acute and severe), which usually starts in the dry form; however, the coexistence of both forms is possible. The etiology of AMD is not fully understood, and the precise mechanisms of the development of this illness are still unknown. Extensive genetic studies have shown that AMD is a multi-factorial disease and that genetic determinants, along with external and internal environmental and metabolic-functional factors, are important risk factors. This article reviews the role of glutathione (GSH) enzymes engaged in maintaining the reduced form and polymorphism in glutathione S-transferase theta-1 (GSTT1) and glutathione S-transferase mu-1 (GSTM1) in the development of AMD. We only chose papers that confirmed the influence of the parameters on the development of AMD. Because GSH is the most important antioxidant in the eye, it is important to know the influence of the enzymes and genetic background to ensure an optimal level of glutathione concentration. Numerous studies have been conducted on how the glutathione system works till today. This paper presents the current state of knowledge about the changes in GSH, GST, GR, and GPx in AMD. GST studies clearly show increased activity in ill people, but for GPx, the results relating to activity are not so clear. Depending on the research, the results also suggest higher and lower GPx activity in patients with AMD. The analysis of polymorphisms in GST genes confirmed that mutations lead to weaker antioxidant barriers and may contribute to the development of AMD; unfortunately, a meta-analysis and some research did not confirm that connection. Unspecific results of many of the parameters that make up the glutathione system show many unknowns. It is so important to conduct further research to understand the exact mechanism of defense functions of glutathione against oxidative stress in the human eye. [ABSTRACT FROM AUTHOR]

Background: The brain is highly susceptible to Aluminium’s (Al) toxic impact due to its elevated lipid content and oxygen utilization but, relatively scanty levels of antioxidants. Al is known for its strong pro-oxidant activity. Hence oxidative stress in the brain is a likely outcome of Al toxicity. Previous studies report sensory, motor and cognitive deficits in animals exposed to various Al compounds. Hence, this study was undertaken to find how dose, and time span of aluminium exposure influence the pro-oxidant activity and antioxidant handling capacity in female Wistar rats’ cerebellum and hippocampus. Materials and Methods: Two groups of female Wistar rats were given four different aluminium chloride oral doses of 0, 50, 100, 200 mg/Kg body weight daily for a time span of four and eight weeks. Oxidative level was assessed by estimating GSH, LPO, SOD, Catalase, GPx and GR in cerebellum and hippocampus of rat brain. Data was analysed by 2-way ANOVA and Bonferroni ‘t’ test was used for multiple group comparisons. Results: Al exposure in female rats resulted in increased lipid peroxidation, while antioxidants GSH, SOD, catalase, GPx and GR were depleted in cerebellum and hippocampus. However, these changes were predominantly significant only in aluminium doses of 100 and 200 mg/Kg in both 4 and 8weeks studies. But, GPx in the cerebellum and catalase in hippocampus showed a crucial reduction even at 50 mg/Kg dose on eight-week exposure. Conclusion: Aluminium has enhanced the synthesis of Reactive Oxygen Species (ROS) in rat cerebellum and hippocampus, as noted by the increase in lipid peroxidation which was not balanced by the elevated synthesis of antioxidants. In addition, aluminium at higher doses of 100mg/Kg dose and more had a significant negative impact on the antioxidant protective system. Therefore, it is vital to minimize our aluminium exposure from different sources in our everyday lives. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) is a chronic disease that usually develops in older people. Pathogenetic changes in this disease include anatomical and functional complexes. Harmful factors damage the retina and macula. These changes may lead to partial or total loss of vision. The disease can occur in two clinical forms: dry (the progression is slow and gentle) and exudative (wet—progression is acute and severe), which usually starts in the dry form; however, the coexistence of both forms is possible. The etiology of AMD is not fully understood, and the precise mechanisms of the development of this illness are still unknown. Extensive genetic studies have shown that AMD is a multi-factorial disease and that genetic determinants, along with external and internal environmental and metabolic-functional factors, are important risk factors. This article reviews the role of glutathione (GSH) enzymes engaged in maintaining the reduced form and polymorphism in glutathione S-transferase theta-1 (GSTT1) and glutathione S-transferase mu-1 (GSTM1) in the development of AMD. We only chose papers that confirmed the influence of the parameters on the development of AMD. Because GSH is the most important antioxidant in the eye, it is important to know the influence of the enzymes and genetic background to ensure an optimal level of glutathione concentration. Numerous studies have been conducted on how the glutathione system works till today. This paper presents the current state of knowledge about the changes in GSH, GST, GR, and GPx in AMD. GST studies clearly show increased activity in ill people, but for GPx, the results relating to activity are not so clear. Depending on the research, the results also suggest higher and lower GPx activity in patients with AMD. The analysis of polymorphisms in GST genes confirmed that mutations lead to weaker antioxidant barriers and may contribute to the development of AMD; unfortunately, a meta-analysis and some research did not confirm that connection. Unspecific results of many of the parameters that make up the glutathione system show many unknowns. It is so important to conduct further research to understand the exact mechanism of defense functions of glutathione against oxidative stress in the human eye.

Mercury (Hg) pollution is a serious environmental and public health problem. Hg has the ability to biomagnify through the trophic chain and generate various pathologies in humans. The exposure of plants to Hg affects normal plant growth and its stress levels, producing oxidative cell damage. Root inoculation with plant growth-promoting bacteria (PGPB) can help reduce the absorption of Hg, minimizing the harmful effects of this metal in the plant. This study evaluates the phytoprotective capacity of four bacterial strains selected for their PGPB capabilities, quantified by the calculation of the biomercuroremediator suitability index (IIBMR), and their consortia, in the Lupinus albus var. orden Dorado. The oxidative stress modulating capacity in the inoculated plant was analyzed by measuring the activity of the enzymes catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione reductase (GR). In turn, the phytoprotective capacity of these PGPBs against the bioaccumulation of Hg was studied in plants grown in soils highly contaminated by Hg vs. soils in the absence of Hg contamination. The results of the oxidative stress alleviation and Hg bioaccumulation were compared with the biometric data of Lupinus albus var. orden Dorado previously obtained under the same soil conditions of Hg concentration. The results show that the biological behavior of plants (biometrics, bioaccumulation of Hg, and activity of regulatory enzymes of reactive oxygen species [ROS]) is significantly improved by the inoculation of strains B1 (Pseudomonas moraviensis) and B2 (Pseudomonas baetica), as well as their corresponding consortium (CS5). In light of the conclusions of this work, the use of these strains, as well as their consortium, is postulated as good candidates for their subsequent use in phytostimulation and phytoprotection processes in areas contaminated with Hg. [ABSTRACT FROM AUTHOR]

Mercury (Hg) pollution is a serious environmental and public health problem. Hg has the ability to biomagnify through the trophic chain and generate various pathologies in humans. The exposure of plants to Hg affects normal plant growth and its stress levels, producing oxidative cell damage. Root inoculation with plant growth-promoting bacteria (PGPB) can help reduce the absorption of Hg, minimizing the harmful effects of this metal in the plant. This study evaluates the phytoprotective capacity of four bacterial strains selected for their PGPB capabilities, quantified by the calculation of the biomercuroremediator suitability index (IIBMR), and their consortia, in the Lupinus albus var. orden Dorado. The oxidative stress modulating capacity in the inoculated plant was analyzed by measuring the activity of the enzymes catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione reductase (GR). In turn, the phytoprotective capacity of these PGPBs against the bioaccumulation of Hg was studied in plants grown in soils highly contaminated by Hg vs. soils in the absence of Hg contamination. The results of the oxidative stress alleviation and Hg bioaccumulation were compared with the biometric data of Lupinus albus var. orden Dorado previously obtained under the same soil conditions of Hg concentration. The results show that the biological behavior of plants (biometrics, bioaccumulation of Hg, and activity of regulatory enzymes of reactive oxygen species [ROS]) is significantly improved by the inoculation of strains B1 (Pseudomonas moraviensis) and B2 (Pseudomonas baetica), as well as their corresponding consortium (CS5). In light of the conclusions of this work, the use of these strains, as well as their consortium, is postulated as good candidates for their subsequent use in phytostimulation and phytoprotection processes in areas contaminated with Hg.

Introduction: An impaired antioxidant status has been described during foetal growth restriction (FGR). Similarly, the antioxidant defence system can be compromised in preterm children with extrauterine growth restriction (EUGR). The aim of this prospective study was to evaluate the antioxidant status in prepubertal children with a history of prematurity without FGR, with and without EUGR, compared to a healthy group.Methods: In total, 211 children were recruited and classified into three groups: 38 with a history of prematurity and EUGR; 50 with a history of prematurity and adequate extrauterine growth (AEUG); and 123 control children born at term. Catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities were assessed in lysed erythrocytes with spectrophotometric methods. Plasma levels of the antioxidants α-tocopherol, retinol and β-carotene were determined through solvent extraction and ultra-high-pressure liquid chromatography coupled to mass spectrometry.Results: Children with the antecedent of EUGR and prematurity had lower CAT activity than the other two groups and lower GPx activity than the control children. Lower SOD, GPx and GR activities were observed in the AEUG group compared to the controls. However, higher concentrations of α-tocopherol and β-carotene were found in the EUGR group compared to the other groups; retinol levels were also higher in EUGR than in AEUG children. In EUGR and AEUG children, enzymatic antioxidant activities and plasma antioxidants were associated with metabolic syndrome components and pro-inflammatory biomarkers.Conclusions: This study reveals, for the first time, that the EUGR condition and prematurity appear to be linked to an impairment of the antioxidant defence status, which might condition an increased risk of adverse metabolic outcomes later in life.

Infertility is a disease that affects the human reproductive system. Infertility is often discovered after marriage and after delayed childbearing because unmarried or married women do not have symptoms that indicate that they are infertile. The study aimed to locate the levels of 1,25-DihydroxyvitaminD3, Glutathione Reductase, Malondialdehyde and Peroxynitrite in infertile males and females compared the results with the control group. The study included forty healthy individuals, divided into twenty males and twenty females, and the other part was forty patients with infertility divided into twenty males and twenty females. Type of study is a case-control study that subjects were matched by age (21-41 years) and body mass index (BMI) (30 or more kg/m2). Blood samples were collected from healthy controls and patients after 12-14 hours of fasting. The study was conducted between March 2019 to September 2019 in the Al- Nahrain University, High Institute for Infertility Diagnosis & Assisted Reproductive Technologies, Iraq. Serum was used to determine DHVD3, GR, FSH, LH, PRL, T, Pg, E2, MDA, and Peroxynitrite. Results were showed a significant decrease in DHVD3, GR and testosterone levels increase in BMI, FSH, LH, PRL, Progesterone, E2, MDA and Peroxynitrite levels in an infertile male group when compared with a control group. In the infertile female group, results showed a significant decrease in DHVD3, GR, Progesterone and E2 levels and increased BMI, FSH, LH, PRL, testosterone, MDA, Peroxynitrite levels when compared with the control group. In conclusion, this study assesses the major associated factors that may affect males and females’ human fertility, especially the oxidative stress parameters and vitamin D deficiency. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of a fluoroquinolone antibiotic, ciprofloxacin on the enzymatic activity of glutathione reductase (GR) in the brain, cardiac, small intestine, and testes tissues of rats. GR enzymes contribute to maintaining appropriate concentrations of intracellular glutathione (GSH). Seventy-two adult male albino rats were divided into four groups (I-IV). Rats in group I (control) were injected with sterile distilled water, whereas animals in experimental groups (II-IV), were injected intraperitoneally with ciprofloxacin in single doses of 100, 150, and 200 mg/kg, respectively. Dosages effects of antibiotic were investigated at three specific periods (in the first, the third, and the seventh hour). The obtained results showed that brain GR activity in ciprofloxacin groups was inhibited compared to the control group all periods (p <0.05). After seven hours, ciprofloxacin found to significantly inhibited the enzyme activity in cardiac tissues especially in group IV (p <0.05). In the II and III groups, however, the small intestine reductase enzyme activity was not affected by ciprofloxacin doses, excluding group IV, where the enzyme activity decreased after seven hours of treatment (P <0.05). As for the GR enzyme activity in rat testis, it was a decrease compared to the control in the treated groups from the start of the third hour to the end of the period (P <0.05). [ABSTRACT FROM AUTHOR]

This study aims at assessing circadian rhythm characteristics of oxidants and antioxidants, testing for any effect of gender, age, diet and smoking status. Blood samples from clinically healthy Indians (103 males and 59 females, 7–75 years of age) were collected at 6-hour intervals for 24 hours for determination of MDA, SOD, CAT, GPx and GR. Data were analyzed by the single and population-mean cosinor to estimate circadian rhythm characteristics. The latter were further analyzed by multi-factor analysis of variance. A marked circadian rhythm was documented for all variables. Its parameters were found to undergo marked changes as a function of age. Males differed from females in terms of the rhythm-adjusted mean (MESOR) of CAT and GPx and of the 24-hour amplitude of GR. The MESOR of GPx differed between vegetarians and omnivores. Smoking status affected the MESOR of MDA and CAT and the 24-hour amplitude of CAT. As oxidative stress is being reported for most diseases, the mapping of circadian rhythms in oxidant and antioxidant enzymes in health may help refine reference values, thereby allowing the early detection of pathophysiological conditions, prompting the early institution of treatment. CAT: Catalase; FRAP: Ferric Reducing Antioxidant Power; GPx: Glutathione Peroxidase; GR: Glutathione Reductase; GSH: Glutathione; MDA: Malondialdehyde; MESOR: Midline Estimating Statistic Of Rhythm; ROS: Reactive Oxygen Species; SCN: Suprachiasmatic Nuclei; SOD: Superoxide Dismutase; TBARs: Thiobarbituric acid reactive substances; XPA: Xeroderma Pigmentosum, Complementation Group A (DNA Damage Recognition And Repair Factor) [ABSTRACT FROM AUTHOR]

Background: Over the past few years, the rapid use of high frequency electromagnetic fields like mobile phones has raised global concerns about the negative health effects of its use. Adaptive response is the ability of a cell or tissue to better resist stress damage by prior exposure to a lesser amount of stress. This study aimed to assess whether radiofrequency radiation can induce adaptive response by changing the antioxidant balance. Materials and Methods: In order to assess RF-induced adaptive response in tissues, we evaluated the level of GSH and the activity of GR in liver. 50 rats were divided into 5 groups. Three groups were pre-exposed to 915 MHz RF radiation, 4 hours per day for one week at different powers, as low, medium and high. 24 hours after the last exposure to radiation, they were exposed to 4 Gy sublethal dose of gamma radiation and then sacrificed after 5 hours. Their livers were removed, washed and were kept at -80o C until used. Results: Our finding showed that pre-exposure to 915 MHz radiofrequency radiation with specific power could induce adaptive response in liver by inducing changes in the activity and level of antioxidant enzymes. Conclusion: It can be concluded that pre-exposure to microwave radiation could increase the level of GSH and the activity of GR enzyme, although these increases were seen just in low power group, and the GR activity was indicated in medium power group. This increase protects tissue from oxidative damage induced by sublethal dose of gamma radiation.

Highlights • POs modulate the expression of antioxidant-related genes in cold-stored grapefruit. • POs induce APX1 mRNA accumulation in grapefruit stored at chilling and non-chilling temperatures. • POs increase MnSOD mRNA levels in grapefruit stored under chilling stress conditions. • POs promote a coordinated transcriptional regulation of the SOD-CAT antioxidant system. • POs treatment modulates GR2 expression at non-chilling temperatures in grapefruit. Abstract Cold storage is one of the main postharvest technologies for fruit preservation, however, cold-sensitive citrus fruits develop peel physiological alterations affecting external quality known as chilling injury (CI). An efficient antioxidant system has been associated to an enhanced cold stress tolerance in citrus fruits. The application of pectic oligosaccharides (POs) stimulates the enzymatic antioxidant system in plants and reduces CI development in grapefruit fruit (Citrus paradisi) during cold storage. The aim of this study was to contribute to the basic understanding of peel physiological disorders in cold-stressed 'Rio Red' grapefruit fruit at ultrastructural level and to determine whether the POs are involved in the CI reduction by modulating the antioxidant enzymatic system at the transcriptional level. Peel morphology in grapefruit fruit stored at chilling (2 °C) and non-chilling (13 °C) temperatures was analyzed by electronic microscopy and the effect of POs treatment on manganese superoxide dismutase (MnSOD), ascorbate peroxidase (APX1), catalase (CAT1) and glutathione reductase (GR2) gene expression was investigated by RT-qPCR. Results indicate that a prolonged cold storage promoted the incidence of CI symptoms in 'Rio Red' grapefruit and altered the ultrastructural morphology of flavedo epidermal tissue. POs significantly modulated the MnSOD, APX1 and CAT1 expression levels mainly in a storage time- and temperature-dependent manner with regards to controls. By contrast, POs only significantly affected the GR2 gene expression when grapefruit were stored at non-chilling temperatures. Our results revealed a possible involvement of the MnSOD, APX1 and CAT1 genes in the CI susceptibility reduction induced by POs in 'Rio Red' grapefruit stored at chilling temperatures. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of aluminum (Al) or selenium (Se) on the “primary” antioxidant defense system enzymes (superoxide dismutase, catalase, and glutathione reductase) in cells of mouse brain and liver after long-term (8-week) exposure to drinking water supplemented with AlCl3 (50 mg or 100 mg Al/L in drinking water) or Na2SeO3 (0.2 mg or 0.4 mg Se/L in drinking water). Results have shown that a high dose of Se increased the activities of superoxide dismutase and catalase in mouse brain and liver. Exposure to a low dose of Se resulted in an increase in catalase activity in mouse brain, but did not show any statistically significant changes in superoxide dismutase activity in both organs. Meanwhile, the administration of both doses of Al caused no changes in activities of these enzymes in mouse brain and liver. The greatest sensitivity to the effect of Al or Se was exhibited by glutathione reductase. Exposure to both doses of Al or Se resulted in statistically significant increase in glutathione reductase activity in both brain and liver. It was concluded that 8-week exposure to Se caused a statistically significant increase in superoxide dismutase, catalase and glutathione reductase activities in mouse brain and/or liver, however, these changes were dependent on the used dose. The exposure to both Al doses caused a statistically significant increase only in glutathione reductase activity of both organs.

This study was conducted to investigate the metabolic defensive mechanism in the larvae of African palm weevil (Rynchophorus phoenicis) administered with dichlorvos (2,2-dichlorovinyl dimethylphosphate) solution. Bioassay experiment with dichlorvos was conducted on the larva and glutathione-utilizing enzyme activities were determined in the major organs: fat body, gut and head of R. phoenicis larva 48 h after treatment with 0-0.060 μg g-1 body weight dichlorvos solution. Glutathione transferase was purified from the gut of larvae by ion-exchange chromatography on diethylaminoethyl- Sephadex A50 and affinity chromatography on glutathione-Sepharose 4B columns. The purified enzyme was homogenous as revealed by sodium dodecylsulfate polyacrylamide gel electrophoresis. Initial velocity studies were carried out on the purified enzyme using standard procedures. Bioassay experiment indicated alterations of glutathione peroxidase, glutathione reductase and glutathione transferase activities in the major organs of larva caused by dichlorvos. Glutathione transferase activity in the gut of larva was three times higher than that of glutathione peroxidase and glutathione reductase activities, an indication of possible detoxification role of glutathione [ABSTRACT FROM AUTHOR]

Plant-derived substances (phytochemicals) are well recognized as sources of pharmacologically potent drugs in the treatment of several oxidative stress related disorders. Our study aims to evaluate the antioxidant and apoptotic effects of Glycyrrhiza glabra L. in both cell free and cell culture system. Plant fractions have been prepared with hexane, chloroform, ethyl acetate, methanol and water and their antioxidant properties are reviewed. Potent antioxidant activity has been well established in both in vitro and in silico studies which is believed to be responsible for the anticancerous nature of the plant. Results obtained indicate that methanol fraction of G. glabra L. exhibited maximum scavenging activity against DPPH and nitric oxide free radicals comparable to standard antioxidant L-AA. Administration of methanol fraction also considerably reduced the malondialdehyde produced due to lipid peroxidation in mammalian liver tissues. Moreover, the levels of antioxidant enzymes SOD, CAT, GST, GPx and GR in the oxidative stress induced tissues were refurbished significantly after treatment with plant’s methanol fraction. Moreover, methanol fraction was found to be nontoxic to normal human cell line whereas it inhibited cancer cells HeLa and HepG2 considerably. Apoptosis was established by DAPI fluorescent staining and western blot analysis of pro apoptotic protein caspase-8, caspase-3 and anti-apoptotic protein Bcl-2.There is an up regulation in the levels of pro apoptotic caspase-8 and caspase-3 and down regulation of anti-apoptotic Bcl-2. Furthermore, GC–MS analysis of the methanol fraction revealed the presence of many compounds. In silico experiments using Autodock 4.2 tools showed strong affinity of plant compounds towards antioxidant enzymes (proteins) thus validating with the conclusions of antioxidant enzyme assays and establishing a role in cancer pathogenesis. [ABSTRACT FROM AUTHOR]

Background: Over the past few years, the rapid use of high frequency electromagnetic fields like mobile phones has raised global concerns about the negative health effects of its use. Adaptive response is the ability of a cell or tissue to better resist stress damage by prior exposure to a lesser amount of stress. This study aimed to assess whether radiofrequency radiation can induce adaptive response by changing the antioxidant balance. Materials and Methods: In order to assess RF-induced adaptive response in tissues, we evaluated the level of GSH and the activity of GR in liver. 50 rats were divided into 5 groups. Three groups were pre-exposed to 915 MHz RF radiation, 4 hours per day for one week at different powers, as low, medium and high. 24 hours after the last exposure to radiation, they were exposed to 4 Gy sublethal dose of gamma radiation and then sacrificed after 5 hours. Their livers were removed, washed and were kept at -80° C until used. Results: Our finding showed that pre-exposure to 915 MHz radiofrequency radiation with specific power could induce adaptive response in liver by inducing changes in the activity and level of antioxidant enzymes. Conclusion: It can be concluded that pre-exposure to microwave radiation could increase the level of GSH and the activity of GR enzyme, although these increases were seen just in low power group, and the GR activity was indicated in medium power group. This increase protects tissue from oxidative damage induced by sublethal dose of gamma radiation. [ABSTRACT FROM AUTHOR]

Several xenobiotic agents (e.g. metals, polycyclic aromatic hydrocarbons, nanoparticles, etc.) commonly involve the generation of reactive oxygen species (ROS) and oxidative stress as part of their toxic mode of action. Among piscine models, the zebrafish is a popular vertebrate model to study toxicity of various xenobiotic agents. Similarly to other vertebrates, zebrafish possess an extensive antioxidant system, including the reduced form of glutathione (GSH), which is an important antioxidant that acts alone or in conjunction with enzymes, such as glutathione peroxidase (GPx). Upon interaction with ROS, GSH is oxidized, resulting in the formation of glutathione disulfide (GSSG). GSSG is recycled by an auxiliary antioxidant enzyme glutathione reductase (GR). This article outlines detailed methods to measure the concentrations of GSH and GSSG, as well as the activities of GPx and GR in zebrafish larvae as robust and economical means to assess oxidative stress. The studies that have assessed these endpoints in zebrafish and alternative methods are also discussed. We conclude that the availability of these robust and economical methods support the use of zebrafish as a model organism in studies evaluating redox biology, as well as the induction of oxidative stress following exposure to toxic agents. [ABSTRACT FROM AUTHOR]

G6PD, 6PGD and GR have been purified separately in the single step from rat lung using 2′, 5′-ADP Sepharose 4B affinity chromatography. The purified enzymes showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weights of the enzymes were estimated to be 134 kDa for G6PD, 107 kDa for 6PGD and 121 kDa for GR by Sephadex G-150 gel filtration chromatography, and the subunit molecular weights was respectively found to be 66, 52 and 63 kDa by SDS-PAGE. Optimum pH, stable pH, optimum ionic strength, optimum temperature,KMandVmaxvalues for substrates were determined. Product inhibition studies were also performed. The enzymes were inhibited by levofloxacin, furosemide, ceftazidime, cefuroxime and gentamicin asin vitrowith IC50values in the range of 0.07–30.13 mM. In vivostudies demonstrated that lung GR was inhibited by furosemide and lung 6PGD was inhibited by levofloxacin. [ABSTRACT FROM PUBLISHER]

The effects of cadmium stress on the growth, antioxidative enzymes and lipid peroxidation in two kenaf plants, Fuhong 991 and ZM412, were analysed under control (0.5-strength Hoagland's nutrient solution) or five levels of cadmium stress (0.5-strength Hoagland's nutrient solution containing different concentrations of Cd2+). The leaves and roots of control and cadmium-stressed plants were harvested after 3 wk. At the same Cd concentration, the Cd tolerance index of Fuhong 991 was higher than that of ZM412, indicating that Fuhong 991 may be more tolerant to Cd than ZM412. The superoxide dismutase (SOD), catalase activity (CAT) and peroxidase (POD) activities fluctuated in the leaves of the Cd-stressed plants compared to the control, whereas the glutathione reductase activity (GR) was much larger than the control for Fuhong 991, ensuring that sufficient quantities of GSH were available to respond to the cadmium stress. In comparison to the control, the dynamic tendency of the SOD, CAT and POD activities in roots of the Cd-stressed plants all increased and then declined, but the POD activity of Fuhong 991 remained nearly unchanged at all of the stress levels. The increase in the enzyme activities demonstrated that Fuhong 991 was more tolerant to cadmium than ZM 412. The lipid peroxidation was enhanced only in the leaves of Cd-stressed ZM 412. These findings indicated that antioxidative activities may play important roles in Cd-stressed Fuhong 991 and ZM 412 and that the leaf and root cell membranes of Fuhong 991 have a greater stability than those of ZM 412. For pollution monitoring purposes, the GR activity in the roots and leaves may serve as a biomarker of Cd for Fuhong 991, whereas lipid peroxidation may serve as biomarker for ZM 412.

Highlights: [•] Glucomannan added or not with spirulina decreased hepatomegalia in Fa/Fa rats. [•] Glucomannan into surimi-diet induced antioxidant but proinflammatory effects. [•] The addition of 3g/kg spirulina kept antioxidant effects and reduced inflammation. [Copyright &y& Elsevier]

Highlights: [•] We examined the role of cysteines in their the V(V)-reductase activity of Vanabin2. [•] When all eighteen cysteine residues were substituted, the activity was lost. [•] Substitutions of three sets of cysteines resulted in a moderate decrease. [•] More than a single cysteine pair is responsible for the V(V)-reductase activity. [ABSTRACT FROM AUTHOR]

Abstract: Accumulating evidence indicates that wide range of polymer based nanoconjugated drug have the ability to overcome the microbial infection. The present study was to evaluate the effects of nanoconjugated chloroquine (Nch) against Plasmodium berghei NK65 (P. berghei) infection on selective makers of oxidative damage, antioxidant status, pro-inflammatory and anti-inflammatory cytokines in liver and spleen. P. berghei infected Swiss mice were treated with Nch (250mg/kg bw for 15 days) compared with chloroquine. The stress markers, pro-inflammatory cytokines were increased significantly (P<0.05) and the anti-oxidant enzymes level, redox ratio (GSH/GSSG), anti-inflammatory markers were decreased significantly (P<0.05) in liver and spleen of infected mice compared with uninfected mice. Chloroquine and Nch effectively decreased the stress markers, pro-inflammatory cytokines, as well as, increased antioxidants level in liver and spleen of the infected mice. Moreover, the favorable effect Nch is better than the chloroquine defending the tissue damage during malarial infection. These findings suggested that the potential use and prospective role of Nch than only chloroquine against P. berghei induced pathology as well as oxidative damage in liver and spleen. [Copyright &y& Elsevier]

Abstract: Glioblastoma, an aggressive brain tumor, has a poor prognosis and a high risk of recurrence. An improved chemotherapeutic approach is required to complement radiation therapy. Gold(I) complexes bearing phosphole ligands are promising agents in the treatment of cancer and disturb the redox balance and proliferation of cancer cells by inhibiting disulfide reductases. Here, we report on the antitumor properties of the gold(I) complex 1-phenyl-bis(2-pyridyl)phosphole gold chloride thio-β-d-glucose tetraacetate (GoPI-sugar), which exhibits antiproliferative effects on human (NCH82, NCH89) and rat (C6) glioma cell lines. Compared to carmustine (BCNU), an established nitrosourea compound for the treatment of glioblastomas that inhibits the proliferation of these glioma cell lines with an IC50 of 430μM, GoPI-sugar is more effective by two orders of magnitude. Moreover, GoPI-sugar inhibits malignant glioma growth in vivo in a C6 glioma rat model and significantly reduces tumor volume while being well tolerated. Both the gold(I) chloro- and thiosugar-substituted phospholes interact with DNA albeit more weakly for the latter. Furthermore, GoPI-sugar irreversibly and potently inhibits thioredoxin reductase (IC50 4.3nM) and human glutathione reductase (IC50 88.5nM). However, treatment with GoPI-sugar did not significantly alter redox parameters in the brain tissue of treated animals. This might be due to compensatory upregulation of redox-related enzymes but might also indicate that the antiproliferative effects of GoPI-sugar in vivo are rather based on DNA interaction and inhibition of topoisomerase I than on the disturbance of redox equilibrium. Since GoPI-sugar is highly effective against glioblastomas and well tolerated, it represents a most promising lead for drug development. This article is part of a Special Issue entitled: Thiol-Based Redox Processes. [Copyright &y& Elsevier]

Abstract: The respiratory chain of the inner mitochondrial membrane is a unique assembly of protein complexes that transfers the electrons of reducing equivalents extracted from foodstuff to molecular oxygen to generate a proton-motive force as the primary energy source for cellular ATP-synthesis. Recent evidence indicates that redox reactions are also involved in regulating mitochondrial function via redox-modification of specific cysteine-thiol groups in subunits of respiratory chain complexes. Vice versa the generation of reactive oxygen species (ROS) by respiratory chain complexes may have an impact on the mitochondrial redox balance through reversible and irreversible thiol-modification of specific target proteins involved in redox signaling, but also pathophysiological processes. Recent evidence indicates that thiol-based redox regulation of the respiratory chain activity and especially S-nitrosylation of complex I could be a strategy to prevent elevated ROS production, oxidative damage and tissue necrosis during ischemia–reperfusion injury. This review focuses on the thiol-based redox processes involving the respiratory chain as a source as well as a target, including a general overview on mitochondria as highly compartmentalized redox organelles and on methods to investigate the redox state of mitochondrial proteins. This article is part of a Special Issue entitled: Thiol-Based Redox Processes. [Copyright &y& Elsevier]

Highlights: [•] Organophosphorus exposure leads to onset and progression of the early steps of type 2 diabetes by the induction of insulin resistance. [•] Insulin resistance is initiated and promoted by glucotoxicity, lipotoxicity, inflammation and oxidative stress. [•] Insulin resistance state is induced by the inhibitory phosphorylation of IRS by a series of serine kinases such as JNK, IKKβ, and PKCθ. [•] Organophosphorus pesticides activate the serine kinases by the induction of hyperglycemia, dyslipidemia, cytokines and reactive oxygen species, leading to insulin resistance. [ABSTRACT FROM AUTHOR]

We studied the response of ethylene-sensitive (Pusa Jai Kisan) and ethylene-insensitive (SS2) mustard (Brassica juncea) cultivars to 0, 0.5, 1.0 and 2.0mM SO4 2−, and the effect of 1.0mM SO4 2− was studied in the amelioration of 50µM cadmium (Cd). The Cd-induced oxidative stress and Cd accumulation were greater in SS2 than Pusa Jai Kisan, but sulfur (S) application alleviated Cd-induced oxidative stress more prominently in Pusa Jai Kisan by increasing S-metabolism and synthesis of reduced glutathione (GSH) and ethylene production; and promoted photosynthesis and plant dry mass under Cd stress. The ethylene-sensitive cultivar responded more to S treatment under Cd stress and showed increased activity of antioxidant system resulting in increased photosynthesis and growth. Cadmium treatment resulted in rapid increase in ethylene formation which adversely influenced photosynthesis and plant dry mass. However, S and ethephon application to Cd-treated plants lowered ethylene formation to optimal range responsible for maximal GSH synthesis and protection against Cd-induced oxidative stress. The similarity of the effectiveness of 1.0mM SO4 2− with 200µLL−1 ethylene source as ethephon in alleviation of 50µM Cd further verifies that differential alleviation of Cd toxicity in the two cultivars by S was dependent on ethylene production. The results suggest that ethylene production determines Cd stress alleviation by S via regulatory interaction with antioxidant metabolism. Thus, ethylene production and sensitivity bear a prominent role in alleviation of Cd stress by S and can be used as a criterion for developing Cd tolerant genotypes. [Copyright &y& Elsevier]

In this study, we comparatively evaluated the effects of the flurochloridone as well as flurochloridone and exogenously applied salicylic acid (SA) on Helianthus annuus L. to find out herbicide-induced toxicity reducing influence of SA. We examined and compared the physiological and biochemical effects of different concentrations of flurochloridone (11, 32 and 72mM) in both the SA pre-treated and non-treated plants. The plants treated with flurochloridone exhibited reduced total chlorophyll, carotenoid, and relative water content compared to the control group, whereas the plants that were pre-treated with SA exhibited relatively higher values for the same physiological parameters. In the SA non-treated plants, the superoxide dismutase, glutathione reductase and glutathione S-transferase activities were increased in the treatment groups compared to the control group. In the treatment groups, these enzyme activities were decreased in the SA-pre-treated plants compared to the non-treated plants. Ascorbate peroxidase and catalase activities decreased in the flurochloridone-treated plants compared to the control plants. The ascorbate peroxidase activity increased in the control groups but decreased in the treatment groups in the SA pre-treated plants compared to the non-treated plants. However, SA treatment decreased the activity of catalase in the control and treatment groups compared to the plants that were not treated with SA. Flurochloridone treatment increased the malondialdehyde content in the treated groups compared to the control groups, whereas SA-pretreatment decreased malondialdehyde content compared to plants that were not treated with SA. Flurochloridone treatment increased endogenous SA content compared to the control. Although the residual levels of herbicide in the plants increased proportionately with increasing herbicide concentrations, the SA-pre-treated plants exhibited reduced residual herbicide levels compared to the plants that were not treated with SA. These results indicate that the flurochloridone induces various physiological and biochemical responses in non-target plants and that treatment with exogenous SA can increase stress resistance by altering these responses. [Copyright &y& Elsevier]

Highlights: [•] Depression induced by chronic unpredictable stress has an impact on brain lipidome. [•] Changes in phospholipidomic profile occurred in the brain of a mouse model of depression. [•] CL oxidation was detected in the brain of a mouse model of depression. [•] Diminished GSH/GSSG corroborates the occurrence of oxidative stress. [•] In myocardium only an increase in PC content was disclosed. [Copyright &y& Elsevier]

Abstract: The nicotinamide adenine dinucleotide phosphate (NADPH) and reduced glutathione (GSH) molecules play important roles in the redox homeostasis of plant cells. Using tomato (Solanum lycopersicum) plants grown with 120mM NaCl, we studied the redox state of NADPH and GSH as well as ascorbate, nitric oxide (NO) and S-nitrosoglutathione (GSNO) content and the activity of the principal enzymes involved in the metabolism of these molecules in roots. Salinity caused a significant reduction in growth parameters and an increase in oxidative parameters such as lipid peroxidation and protein oxidation. Salinity also led to an overall decrease in the content of these redox molecules and in the enzymatic activities of the main NADPH-generating dehydrogenases, S-nitrosoglutathione reductase and catalase. However, NO content as well as gluthahione reductase and glutathione peroxidase activity increased under salinity stress. These findings indicate that salinity drastically affects redox and NO homeostasis in tomato roots. In our view, these molecules, which show the interaction between ROS and RNS metabolisms, could be excellent parameters for evaluating the physiological conditions of plants under adverse stress conditions. [Copyright &y& Elsevier]

Highlights: [•] QUIN decreased the level of GSH in the rat striatum. [•] SULF avoid the decrease of GSH levels in the rat striatum. [•] SULF increased enzymes activity related to regeneration of GSH levels. [•] SULF ameliorated the QUIN-induced behavioral and morphological alterations. [ABSTRACT FROM AUTHOR]

Abstract: Background: Mammalian thioredoxin reductases (TrxR) are selenoproteins with important roles in antioxidant defense and redox regulation, principally linked to functions of their main substrates thioredoxins (Trx). All major forms of TrxR are intracellular while levels in serum are typically very low. Methods: Serum TrxR levels were determined with immunoblotting using antibodies against mouse TrxR1 and total enzyme activity measurements were performed, with serum and tissue samples from mouse models of liver injury, as triggered by either thioacetamide (TAA) or carbon tetrachloride (CCl4). Results: TrxR levels in serum increased upon treatment and correlated closely with those of alanine aminotransferase (ALT), an often used serum biomarker for liver damage. In contrast, Trx1, glutathione reductase, superoxide dismutase or selenium-containing glutathione peroxidase levels in serum displayed much lower increases than TrxR or ALT. Conclusions: Serum TrxR levels are robustly elevated in mouse models of chemically induced liver injury. General significance: The exaggerated TrxR release to serum upon liver injury may reflect more complex events than a mere passive release of hepatic enzymes to the extracellular milieu. It can also not be disregarded that enzymatically active TrxR in serum could have yet unidentified physiological functions. [Copyright &y& Elsevier]

Abstract: The influence of salicylic acid (SA) in alleviation of salt stress in mungbean (Vigna radiata L.) through modulation of glycinebetaine (GB) and ethylene was studied. SA application at 0.5 mM increased methionine (Met) and GB accumulation in plants concomitant with the suppression of ethylene formation by inhibiting 1-aminocyclopropane carboxylic acid synthase (ACS) activity more conspicuously under salt stress than no stress. The increased GB accumulation together with reduced ethylene under salt stress by SA application was associated with increased glutathione (GSH) content and lower oxidative stress. These positive effects on plant metabolism induced by SA application led to improved photosynthesis and growth under salt stress. These results suggest that SA induces GB accumulation through increased Met and suppresses ethylene formation under salt stress and enhances antioxidant system resulting in alleviation of adverse effects of salt stress on photosynthesis and growth. These effects of SA were substantiated by the findings that application of SA-analogue, 2, 6, dichloro-isonicotinic acid (INA) and ethylene biosynthesis inhibitor, aminoethoxyvinylglycine (AVG) resulted in similar effects on Met, GB, ethylene production, photosynthesis and growth under salt stress. Future studies on the interaction between SA, GB and ethylene could be exploited for adaptive responses of plants under salt stress. [Copyright &y& Elsevier]

Abstract: Reactive oxygen species are the main contributors to seed deterioration. In order to study scavenging systems for reactive oxygen species in aged seed, we performed analyses using western blotting, real-time quantitative reverse-transcription polymerase chain reaction, high-performance liquid chromatography, and antioxidant enzyme activity analyses in artificially aged rice seeds (Oryza sativa L. cv. wanhua no.11). Aging seeds by storing them at 50 °C for 1, 9, or 17 months increased the superoxide radical and hydrogen peroxide levels and reduced the germination percentage from 99% to 92%, 55%, and 2%, respectively. The activity levels of superoxide dismutase (SOD), glutathione reductase (GR), and dehydroascorbate reductase (DHAR) did not change in aged seeds. In contrast, the activity levels of catalase (CAT), ascorbate peroxidase (APX), and monodehydroascorbate reductase (MDHAR) were significantly decreased in aged seeds, as were the expression of catalase and cytosolic ascorbate peroxidase protein. Transcript accumulation analysis showed that specific expression patterns were complex for each of the antioxidant enzyme types in the rice embryos. Overall, the expression of most genes was down-regulated, along with their protein expression. In addition, the reduction in the amount of ascorbate and glutathione was associated with the reduction in scavenging enzymes activity in aged rice embryos. Our data suggest that the depression of the antioxidant system, especially the reduction in the expression of CAT1, APX1 and MDHAR1, may be responsible for the accumulation of reactive oxygen species in artificially aged seed embryos, leading to a loss of seed vigor. [Copyright &y& Elsevier]

In this report, the effect of hydrogen-rich water (HRW), which was used to investigate the physiological roles of hydrogen gas (H2) in plants recently, on the regulation of plant adaptation to mercury (Hg) toxicity was studied. Firstly, we observed that the exposure of alfalfa seedlings to HgCl2 triggered production of reactive oxygen species (ROS), growth stunt and increased lipid peroxidation. However, such effects could be obviously blocked by HRW. Meanwhile, significant decreases in the relative ion leakage and Hg accumulation were observed. Hg-induced increases in total and isozymatic activities of superoxide dismutase (SOD) were significantly reversed by HRW. Further results suggested that HRW-induced the activities of guaiacol peroxidase (POD) and ascorbate peroxidase (APX), two hydrogen peroxide-scavenging enzymes, was at transcriptional levels. Meanwhile, obvious increases of the ratios of reduced/oxidized glutathione (GSH), homoglutathione (hGSH), and ascorbic acid (AsA) and corresponding gene expression were consistent with the decreased oxidative damage in seedling roots. In summary, the results of this investigation indicated that HRW was able to alleviate Hg toxicity in alfalfa seedlings by (i) alleviating growth stunt and reducing Hg accumulation, and (ii) avoidance of oxidative stress and reestablishment of redox homeostasis. [Copyright &y& Elsevier]

Abstract: Aims: Preventive and/or therapeutic interventions using natural products for ischemic heart disease have gained considerable attention worldwide. This study investigated the cardioprotective effect and possible mechanism of embelin, a major constituent of Embelia ribes Burm, using isoproterenol (ISO)-induced myocardial infarction model in rats. Materials and methods: Rats were pretreated for three days with embelin (50mg/kg, p.o) before inducing myocardial injury by administration of ISO (85mg/kg) subcutaneously at an interval of 24h for 2 consecutive days. Serum was analyzed for cardiac specific injury biomarkers, lipids and lipoprotein content. Heart tissues were isolated and were used for histopathology, antioxidant and mitochondrial respiratory enzyme activity assays and western blot analysis. Key findings: Results showed that pretreatment with embelin significantly decreased the elevated levels of serum specific cardiac injury biomarkers (CK-MB, LDH and AST), serum levels of lipids and lipoproteins and histopathological changes when compared to ISO-induced controls. Exploration of the underlying mechanisms of embelin action revealed that embelin pretreatment restored the myocardial mitochondrial respiratory enzyme activities (NADH dehydrogenase, succinate dehydrogenase, cytochrome c oxidase and mitochondrial redox activity), strengthened antioxidant status and attenuated ISO-induced myocardial lipid peroxidation. Immunoblot analysis revealed that embelin interrupted mitochondria dependent apoptotic damage by increasing the myocardial expression of Bcl-2 and downregulating the expression of Bax, cytochrome c, cleaved-caspase-3 & 9 and PARP. Histopathology findings further strengthened the cardioprotective findings of embelin. Significance: Result suggested that embelin may have a potential benefit in preventing ischemic heart disease like myocardial infarction. [Copyright &y& Elsevier]

Abstract: A vacuolar proton pyrophosphatase cDNA clone was isolated from Sorghum bicolor (SbVPPase) using end-to-end gene-specific primer amplification. It showed 80–90% homology at the nucleotide and 85–95% homology at the amino acid level with other VPPases. The gene was introduced into expression vector pCAMBIA1301 under the control of the cauliflower mosaic virus 35S (CaMV35S) promoter and transformed into Agrobacterium tumifaciens strain LBA4404 to infect embryogenic calli of finger millet (Eleusine coracana). Successful transfer of SbVPPase was confirmed by a GUS histochemical assay and PCR analysis. Both, controls and transgenic plants were subjected to 100 and 200mM NaCl and certain biochemical and physiological parameters were studied. Relative water content (RWC), plant height, leaf expansion, finger length and width and grain weight were severely reduced (50–70%), and the flowering period was delayed by 20% in control plants compared to transgenic plants under salinity stress. With increasing salt stress, the proline and chlorophyll contents as well as the enzyme activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and glutathione reductase (GR) increased by 25–100% in transgenics, while malondialdehyde (MDA) showed a 2–4-fold decrease. The increased activities of antioxidant enzymes and the reduction in the MDA content suggest efficient scavenging of reactive oxygen species (ROS) in transgenics and, as a consequence, probably alleviation of salt stress. Also, the leaf tissues of the transgenics accumulated 1.5–2.5-fold higher Na+ and 0.4–0.8-fold higher K+ levels. Together, these results clearly demonstrate that overexpression of SbVPPase in transgenic finger millet enhances the plant's performance under salt stress. [Copyright &y& Elsevier]

Abstract: A deficiency of mitochondrial glutathione reductase (or GR2) is capable of adversely affecting the reduction of GSSG and increasing mitochondrial oxidative stress. BCNU [1,3-bis (2-chloroethyl)-1-nitrosourea] is an anticancer agent and known inhibitor of cytosolic GR ex vivo and in vivo. Here we tested the hypothesis that a BCNU-induced GR2 defect contributes to mitochondrial dysfunction and subsequent impairment of heart function. Intraperitoneal administration of BCNU (40mg/kg) specifically inhibited GR2 activity by 79.8±2.7% in the mitochondria of rat heart. However, BCNU treatment modestly enhanced the activities of mitochondrial Complex I and other ETC components. The cardiac function of BCNU-treated rats was analyzed by echocardiography, revealing a systolic dysfunction associated with decreased ejection fraction, decreased cardiac output, and an increase in left ventricular internal dimension and left ventricular volume in systole. The respiratory control index of isolated mitochondria from the myocardium was moderately decreased after BCNU treatment, whereas NADH-linked uncoupling of oxygen consumption was significantly enhanced. Extracellular flux analysis to measure the fatty acid oxidation of myocytes indicated a 20% enhancement after BCNU treatment. When the mitochondria were immunoblotted with antibodies against GSH and UCP3, both protein S-glutathionylation of Complex I and expression of UCP3 were significantly up-regulated. Overexpression of SOD2 in the myocardium significantly reversed BCNU-induced GR2 inhibition and mitochondrial impairment. In conclusion, BCNU-mediated cardiotoxicity is characterized by the GR2 deficiency that negatively regulates heart function by impairing mitochondrial integrity, increasing oxidative stress with Complex I S-glutathionylation, and enhancing uncoupling of mitochondrial respiration. [Copyright &y& Elsevier]

Abstract: Oxidative stress is considered one of the main ecological and evolutionary forces. Several environmental stressors vary geographically and thus organisms inhabiting different sites face different oxidant environments. Nevertheless, there is scarce information about how oxidative damage and antioxidant defences vary geographically in animals. Here we study how oxidative stress varies from lowlands (300–700m asl) to highlands (2200–2500m asl) in the lizard Psammodromus algirus. To accomplish this, antioxidant enzymatic activity (catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione transferase, DT-diaphorase) and lipid peroxidation were assayed in tissue samples from the lizards' tail. Lipid peroxidation was higher in individuals from lowlands than from highlands, indicating higher oxidative stress in lowland lizards. These results suggest that environmental conditions are less oxidant at high elevations with respect to low ones. Therefore, our study shows that oxidative stress varies geographically, which should have important consequences for our understanding of geographic variation in physiology and life-history of organisms. [Copyright &y& Elsevier]

Abstract: This review provides an overview about recent developments and current knowledge about monitoring, generation and the functional role of reactive oxygen species (ROS) – H2O2, HO2 , HO , OH−, 1O2 and O2 − – in both oxidative degradation and signal transduction in photosynthetic organisms including microscopic techniques for ROS detection and controlled generation. Reaction schemes elucidating formation, decay and signaling of ROS in cyanobacteria as well as from chloroplasts to the nuclear genome in eukaryotes during exposure of oxygen-evolving photosynthetic organisms to oxidative stress are discussed that target the rapidly growing field of regulatory effects of ROS on nuclear gene expression. [Copyright &y& Elsevier]

Highlights: [•] The present study aims to unravel the nano-CuO stress impact on Syrian barley. [•] Nano-stress has no significant effect on maximal quantum yield of PSII (Fv/Fm). [•] Histochemical DAB staining indicates severe oxidative burst under prolonged stress. [•] Enhanced APX activity is insufficient to enforce a light control over H2O2 level. [•] Concomitant decline in DHAR and MDAR results futile recycling of ascorbate pool. [ABSTRACT FROM AUTHOR]

Abstract: Myeloperoxidase is an important heme enzyme released by activated leukocytes that catalyzes the reaction of hydrogen peroxide with halide and pseudo-halide ions to form various hypohalous acids. Hypohalous acids are chemical oxidants that have potent antibacterial, antiviral, and antifungal properties and, as such, play key roles in the human immune system. However, increasing evidence supports an alternative role for myeloperoxidase-derived oxidants in the development of disease. Excessive production of hypohalous acids, particularly during chronic inflammation, leads to the initiation and accumulation of cellular damage that has been implicated in many human pathologies including atherosclerosis, neurodegenerative disease, lung disease, arthritis, inflammatory cancers, and kidney disease. This has sparked a significant interest in developing a greater understanding of the mechanisms involved in myeloperoxidase-derived oxidant-induced mammalian cell damage. This article reviews recent developments in our understanding of the cellular reactivity of hypochlorous acid, hypobromous acid, and hypothiocyanous acid, the major oxidants produced by myeloperoxidase under physiological conditions. [Copyright &y& Elsevier]

Highlights: [•] TCDD-induced phytotoxicity is demonstrated by several biological damages. [•] An enhanced level H2O2 is detected in Arabidopsis tissues after TCDD-exposure. [•] Endogenous anti-oxidative enzyme activities are highly stimulated by TCDD. [•] TCDD uptake by Arabidopsis is detected in roots more than in shoot. [•] By tissues-specific way, TCDD modulates the expression of specific TF genes. [Copyright &y& Elsevier]

Abstract: Ochratoxin A (OTA) is one of the most toxic mycotoxins, which is toxic to plants and simulates oxidative stress. Glutathione is an important antioxidant in plants and is closely associated with detoxification in cells. We have previously shown that OTA exposure induces obvious expression differences in genes associated with glutathione metabolism. To characterize glutathione metabolism and understand its role in OTA phytotoxicity, we observed the accumulation of GSH in the detached leaves of Arabidopsis thaliana under OTA treatment. OTA stimulated a defense response through enhancing glutathione-S-transferase, glutathione peroxidase, glutathione reductase activities, and the transcript levels of these enzymes were increased to maintain the total glutathione content. Moreover, the level of oxidized glutathione (GSSG) was increased and the ascorbate–glutathione cycle fluctuated in response to OTA. The depletion of glutathione using buthionine sulfoximine (BSO, inhibitor of glutamate–cysteine ligase) had no profound effect on OTA toxicity, as glutathione was regenerated through the ascorbate–glutathione cycle to maintain the total glutathione content. The ROS, MDA and GSH accumulation was significantly affected in the mutant gsh1, gr1 and gpx2 after treatment with OTA, which indicated that glutathione metabolism is directly involved in the oxidative stress response of Arabidopsis thaliana subjected to OTA. In conclusion, date demonstrate that glutathione-associated metabolism is closely related with OTA stress and glutathione play a role in resistance of Arabidopsis subjected to OTA. [Copyright &y& Elsevier]

Plant Growth Promoting Rhizobacteria (PGPR), whose role is still underestimated, plays an important (or perhaps essential) role in improving plant growth. The comprehensive understanding of bacterial plant growth promoting mechanism helps to get sustainable agriculture production under biotic and abiotic stresses. In the present study, plant growth promoting (PGP) bacterial strain Pseudomonas aeruginosa having maximum inhibitory concentration of 1500mgkg−1 against Zn was isolated from arable land, irrigated with industrial effluent and evaluated to determine it bioremediation potential. The study was mainly focused on plant biomass production, nutrient uptake and oxidative stress tolerance in relation to the activities of antioxidative enzymes and the content of non-enzymatic antioxidants. The oxidative stress tolerance was measured by estimating the MDA accumulation as well as H2O2 production in wheat plants under Zn (1000mgkg−1) stress and inoculation of soil with Zn resistant Pseudomonas aeruginosa. Zn in rooting medium reduced the plant growth, leaf photosynthetic pigments as well as uptake of N and P. However, content of MDA and H2O2 increased at higher concentration of Zn. Inoculation of P. aeruginosa improved the uptake of P and N in wheat plants with an increase in leaf chlorophyll, total soluble protein and plant biomass production. Analysis of plant root and shoot disclosed that Zn concentration was significantly lowered in P. aeruginosa inoculated zinc stressed plants as compare to the plants grown under Zn stress only. The amelioration of adverse effects of Zn stress on biomass production due to P. aeruginosa inoculation was related with enhanced antioxidative enzyme activities (SOD, POD and CAT), and the contents of non-enzymatic components such as ascorbic acid and total phenolics (TPC) as compare to Zn-treated plants. The up-gradation in antioxidative defense mechanism, resulted a reduction in H2O2 and MDA content due to the scavenging of ROS by antioxidants. It was concluded that P. aeruginosa is an ideal candidate for bioremediation and wheat growth promotion against Zn-induced oxidative stress by improving the availability of necessary nutrient, eliciting antioxidant defense system as well as by lowering the Zn metal uptake. [Copyright &y& Elsevier]

Jasmonic acid (JA) is regarded as endogenous regulator that plays an important role in regulating stress responses, plant growth and development. To investigate the physiological mechanisms of salt stress mitigated by exogenous JA, foliar application of 2mM JA was done to wheat seedlings for 3days and then they were subjected to 150mM NaCl. Our results showed that 150mM NaCl treatment significantly decreased plant height, root length, shoot dry weight, root dry weight, the concentration of glutathione (GSH), chlorophyll b (Chl b) and carotenoid (Car), the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), enhanced the concentration of malondialdehyde (MDA), hydrogen peroxide (H2O2) and the rate of superoxide radical ( ) generation in the wheat seedlings when compared with the control. However, treatments with exogenous JA for 3days significantly enhanced salt stress tolerance in wheat seedlings by decreasing the concentration of MDA and H2O2, the production rate of and increasing the transcript levels and activities of SOD, POD, CAT and APX and the contents of GSH, Chl b and Car, which, in turn, enhanced the growth of salt stressed seedlings. These results suggested that JA could effectively protect wheat seedlings from salt stress damage by enhancing activities of antioxidant enzymes and the concentration of antioxidative compounds to quench the excessive reactive oxygen species caused by salt stress and presented a practical implication for wheat cultivation in salt-affected soils. [Copyright &y& Elsevier]

Abstract: In order to establish a physiological link between antioxidases and the resistance level of insects to cadmium (Cd), natural populations of Boettcherisca peregrina (Diptera: Sarcophagidae) were maintained for 20 generations and reared either on an uncontaminated diet or on a diet contaminated with cadmium (Cd) at a concentration equivalent to the median lethal concentration (LC50) as determined every five generations. A relatively susceptible strain (S) and a Cd-resistant strain (R) were selected. The metal accumulation, growth and development, reproduction, and antioxidant enzyme activities in these strains were analyzed. The results showed that R-strain organisms had enhanced juvenile survivorship, increased Cd accumulation, and increased adult female fecundity when compared with S-strain. The larval enzyme activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione S-transferase (GST) in R-strain larvae were higher than those in S-strain larvae when fed diets with or without Cd. This indicates that Cd resistance in B. peregrina larvae is mediated by SOD, CAT, GR, and GST. [Copyright &y& Elsevier]