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Sample records for aba-induced antioxidant defense

  1. Phosphorylation of a NAC Transcription Factor by a Calcium/Calmodulin-Dependent Protein Kinase Regulates Abscisic Acid-Induced Antioxidant Defense in Maize.

    PubMed

    Zhu, Yuan; Yan, Jingwei; Liu, Weijuan; Liu, Lei; Sheng, Yu; Sun, Yue; Li, Yanyun; Scheller, Henrik Vibe; Jiang, Mingyi; Hou, Xilin; Ni, Lan; Zhang, Aying

    2016-07-01

    Calcium/calmodulin-dependent protein kinase (CCaMK) has been shown to play an important role in abscisic acid (ABA)-induced antioxidant defense and enhance the tolerance of plants to drought stress. However, its downstream molecular events are poorly understood. Here, we identify a NAC transcription factor, ZmNAC84, in maize (Zea mays), which physically interacts with ZmCCaMK in vitro and in vivo. ZmNAC84 displays a partially overlapping expression pattern with ZmCCaMK after ABA treatment, and H2O2 is required for ABA-induced ZmNAC84 expression. Functional analysis reveals that ZmNAC84 is essential for ABA-induced antioxidant defense in a ZmCCaMK-dependent manner. Furthermore, ZmCCaMK directly phosphorylates Ser-113 of ZmNAC84 in vitro, and Ser-113 is essential for the ABA-induced stimulation of antioxidant defense by ZmCCaMK. Moreover, overexpression of ZmNAC84 in tobacco (Nicotiana tabacum) can improve drought tolerance and alleviate drought-induced oxidative damage of transgenic plants. These results define a mechanism for ZmCCaMK function in ABA-induced antioxidant defense, where ABA-produced H2O2 first induces expression of ZmCCaMK and ZmNAC84 and activates ZmCCaMK. Subsequently, the activated ZmCCaMK phosphorylates ZmNAC84 at Ser-113, thereby inducing antioxidant defense by activating downstream genes.

  2. Abscisic acid activates a Ca2+-calmodulin-stimulated protein kinase involved in antioxidant defense in maize leaves.

    PubMed

    Xu, Shucheng

    2010-09-01

    The role of a calcium-dependent and calmodulin (CaM)-stimulated protein kinase in abscisic acid (ABA)-induced antioxidant defense was determined in leaves of maize (Zea mays). In-gel kinase assays showed that treatments with ABA or H(2)O(2) induced the activation of a 49-kDa protein kinase and a 52-kDa protein kinase significantly. Furthermore, we showed that the 52-kDa protein kinase has the characteristics of CaM-stimulating activity and is sensitive to calcium-CaM-dependent protein kinase II (CaMK II) inhibitor KN-93 or CaM antagonist W-7. Treatments with ABA or H(2)O(2) not only induced the activation of the 52-kDa protein kinase, but also enhanced the total activities of the antioxidant enzymes, including catalase, ascorbate peroxidase, glutathione reductase, and superoxide dismutase. Such enhancements were blocked by pretreatment with a CaMK inhibitor and a reactive oxygen species (ROS) inhibitor or scavenger. Pretreatment with the CaMK inhibitor also substantially arrested the ABA-induced H(2)O(2) production. Kinase activity enhancements induced by ABA were attenuated by pretreatment with an ROS inhibitor or scavenger. These results suggest that the 52-kDa CaMK is involved in ABA-induced antioxidant defense and that cross-talk between CaMK and H(2)O(2) plays a pivotal role in ABA signaling. We infer that CaMK acts both upstream and downstream of H(2)O(2), but mainly acts between ABA and H(2)O(2) in ABA-induced antioxidant-defensive signaling.

  3. Calcium-calmodulin is required for abscisic acid-induced antioxidant defense and functions both upstream and downstream of H2O2 production in leaves of maize (Zea mays) plants.

    PubMed

    Hu, Xiuli; Jiang, Mingyi; Zhang, Jianhua; Zhang, Aying; Lin, Fan; Tan, Mingpu

    2007-01-01

    * Using pharmacological and biochemical approaches, the role of calmodulin (CaM) and the relationship between CaM and hydrogen peroxide (H(2)O(2)) in abscisic acid (ABA)-induced antioxidant defense in leaves of maize (Zea mays) plants were investigated. * Treatment with ABA or H(2)O(2) led to significant increases in the concentration of cytosolic Ca(2+) in the protoplasts of mesophyll cells and in the expression of the calmodulin 1 (CaM1) gene and the content of CaM in leaves of maize plants, and enhanced the expression of the antioxidant genes superoxide dismutase 4 (SOD4), cytosolic ascorbate peroxidase (cAPX), and glutathione reductase 1 (GR1) and the activities of the chloroplastic and cytosolic antioxidant enzymes. The up-regulation of the antioxidant enzymes was almost completely blocked by pretreatments with two CaM antagonists. * Pretreatments with CaM antagonists almost completely inhibited ABA-induced H(2)O(2) production throughout ABA treatment, but pretreatment with an inhibitor or scavenger of reactive oxygen species (ROS) did not affect the initial increase in the contents of CaM induced by ABA. * Our results suggest that Ca(2+)-CaM is involved in ABA-induced antioxidant defense, and that cross-talk between Ca(2+)-CaM and H(2)O(2) plays a pivotal role in ABA signaling.

  4. Free radicals, antioxidant defense systems, and schizophrenia.

    PubMed

    Wu, Jing Qin; Kosten, Thomas R; Zhang, Xiang Yang

    2013-10-01

    The etiopathogenic mechanisms of schizophrenia are to date unknown, although several hypotheses have been suggested. Accumulating evidence suggests that excessive free radical production or oxidative stress may be involved in the pathophysiology of schizophrenia as evidenced by increased production of reactive oxygen or decreased antioxidant protection in schizophrenic patients. This review aims to summarize the basic molecular mechanisms of free radical metabolism, the impaired antioxidant defense system and membrane pathology in schizophrenia, their interrelationships with the characteristic clinical symptoms and the implications for antipsychotic treatments. In schizophrenia, there is accumulating evidence of altered antioxidant enzyme activities and increased levels of lipid peroxidation, as well as altered levels of plasma antioxidants. Moreover, free radical-mediated abnormalities may contribute to specific aspects of schizophrenic symptomatology and complications of its treatment with antipsychotic drugs, as well as the development of tardive dyskinesia (TD). Finally, the potential therapeutic strategies implicated by the accumulating data on oxidative stress mechanisms for the treatment of schizophrenia are discussed.

  5. Brassinosteroids modulate ABA-induced stomatal closure in Arabidopsis

    PubMed Central

    Ha, Yunmi; Shang, Yun; Nam, Kyoung Hee

    2016-01-01

    Stomatal movement in response to water availability is an important physiological process in the survival of land plants. The plant hormone abscisic acid (ABA) and brassinosteroids (BRs) regulate stomatal closure. The physiological functions of ABA and BRs, including germination, cell elongation and stomatal movement, are generally known to be antagonistic. Here, we investigated how BRs affect stomatal movement alone and in combination with ABA. We demonstrate that brassinoslide (BL), the most active BR, promotes stomatal closure in an ABA-independent manner. Interestingly, BL also inhibited ABA-induced stomatal closure when a high concentration of BL was added to ABA. Furthermore, we found that the induction of some genes for reactive oxygen species (ROS) generation by ABA (AtrbohD, NIA1 and NIA2) and subsequent ROS production were repressed by BL treatment. The BR signaling mutant bri1-301 failed to inhibit ABA-induced stomatal closure upon BL treatment. However, BRI1-overexpressing transgenic plants were hypersensitive to ABA during stomatal closure, and BL reversed ABA-induced stomatal closure more completely than in wild type plants. Taken together, these results suggest that BRs can positively and negatively modulate ABA-induced stomatal closure. Therefore, interactions between ABA and BR signaling are important for the regulation of stomatal closure. PMID:27856707

  6. Effect of Terminalia arjuna on antioxidant defense system in cancer.

    PubMed

    Verma, Nibha; Vinayak, Manjula

    2009-01-01

    Constant production of reactive oxygen species (ROS) during aerobic metabolism is balanced by antioxidant defense system of an organism. Although low level of ROS is important for various physiological functions, its accumulation has been implicated in the pathogenesis of age-related diseases such as cancer and coronary heart disease and neurodegenerative disorders such as Alzheimer's disease. It is generally assumed that frequent consumption of phytochemicals derived from vegetables, fruits, tea and herbs may contribute to shift the balance towards an adequate antioxidant status. The present study is aimed to investigate the effect of aqueous extract of medicinal plant Terminalia arjuna on antioxidant defense system in lymphoma bearing AKR mice. Antioxidant action of T. arjuna is monitored by the activities of catalase, superoxide dismutase and glutathione S transferase which constitute major antioxidant defense system by scavenging ROS. These enzyme activities are low in lymphoma bearing mice indicating impaired antioxidant defense system. Oral administration of different doses of aqueous extract of T. arjuna causes significant elevation in the activities of catalase, superoxide dismutase and glutathione S transferase. T. arjuna is found to down regulate anaerobic metabolism by inhibiting the activity of lactate dehydrogenase in lymphoma bearing mice, which was elevated in untreated cancerous mice. The results indicate the antioxidant action of aqueous extract of T. arjuna, which may play a role in the anti carcinogenic activity by reducing the oxidative stress along with inhibition of anaerobic metabolism.

  7. Leptin Improves Sperm Cryopreservation via Antioxidant Defense

    PubMed Central

    Fontoura, Paula; Mello, Mariana Duque; Gallo-Sá, Paulo; Erthal-Martins, Maria Cecília; Cardoso, Maria Cecília Almeida; Ramos, Cristiane

    2017-01-01

    Background: Leptin and its receptor are present in spermatozoa; however, the role of leptin in sperm function is still controversial. Our present study aimed at demonstrating the effect of cryopreservation on sperm DNA fragmentation (DNAf) and investigating the possible effects of sperm capacitation techniques and leptin in vitro incubation on frozen-thawed sperm DNAf and oxidative stress. Methods: Samples of 45 normospermic men attending for infertility investigation at Vida Centro de Fertilidade, Rio de Janeiro, Brazil, were frozen and thawed with or without capacitation and leptin incubation prior to freezing. Sperm DNA fragmentation was evaluated by Sperm Chromatin Dispersion Assay before and after cryopreservation and oxidative stress parameters were measured by spectrophotometry with and without leptin incubation. Statistical analysis was performed using paired t test to compare DNAf between groups before and after freeze-thaw cycle, to compare groups before and after capacitation and leptin incubation and oxidative measurements before and after leptin incubation. Statistical significance was considered when p≤0.05. Results: Our results revealed a significant post-thaw rise in sperm DNAf compared with fresh samples (p=0.0003). Sperm DNAf was significantly reduced when sperm capacitation was performed before freezing, when compared to those frozen with no previous capacitation (p=0.01). The addition of leptin to capacitated sperm before freezing reduced DNAf (p<0.0001) and enhanced superoxide dismutase (p=0.001) and glutathione peroxidase (p=0.02) antioxidant enzymes activity. Conclusion: The addition of leptin to capacitated sperm can improve sperm DNA quality following cryopreservation, possibly by inducing the activity of certain antioxidant enzymes. PMID:28377896

  8. Antioxidant Defenses in the Brains of Bats during Hibernation.

    PubMed

    Yin, Qiuyuan; Ge, Hanxiao; Liao, Chen-Chong; Liu, Di; Zhang, Shuyi; Pan, Yi-Hsuan

    2016-01-01

    Hibernation is a strategy used by some mammals to survive a cold winter. Small hibernating mammals, such as squirrels and hamsters, use species- and tissue-specific antioxidant defenses to cope with oxidative insults during hibernation. Little is known about antioxidant responses and their regulatory mechanisms in hibernating bats. We found that the total level of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the brain of each of the two distantly related hibernating bats M. ricketti and R. ferrumequinum at arousal was lower than that at torpid or active state. We also found that the levels of malondialdehyde (product of lipid peroxidation) of the two hibernating species of bats were significantly lower than those of non-hibernating bats R. leschenaultia and C. sphinx. This observation suggests that bats maintain a basal level of ROS/RNS that does no harm to the brain during hibernation. Results of Western blotting showed that hibernating bats expressed higher amounts of antioxidant proteins than non-hibernating bats and that M. ricketti bats upregulated the expression of some enzymes to overcome oxidative stresses, such as superoxide dismutase, glutathione reductase, and catalase. In contrast, R. ferrumequinum bats maintained a relatively high level of superoxide dismutase 2, glutathione reductase, and thioredoxin-2 throughout the three different states of hibernation cycles. The levels of glutathione (GSH) were higher in M. ricketti bats than in R. ferrumequinum bats and were significantly elevated in R. ferrumequinum bats after torpor. These data suggest that M. ricketti bats use mainly antioxidant enzymes and R. ferrumequinum bats rely on both enzymes and low molecular weight antioxidants (e.g., glutathione) to avoid oxidative stresses during arousal. Furthermore, Nrf2 and FOXOs play major roles in the regulation of antioxidant defenses in the brains of bats during hibernation. Our study revealed strategies used by bats against oxidative

  9. Antioxidant Defenses in the Brains of Bats during Hibernation

    PubMed Central

    Yin, Qiuyuan; Ge, Hanxiao; Liao, Chen-Chong; Liu, Di; Zhang, Shuyi; Pan, Yi-Hsuan

    2016-01-01

    Hibernation is a strategy used by some mammals to survive a cold winter. Small hibernating mammals, such as squirrels and hamsters, use species- and tissue-specific antioxidant defenses to cope with oxidative insults during hibernation. Little is known about antioxidant responses and their regulatory mechanisms in hibernating bats. We found that the total level of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the brain of each of the two distantly related hibernating bats M. ricketti and R. ferrumequinum at arousal was lower than that at torpid or active state. We also found that the levels of malondialdehyde (product of lipid peroxidation) of the two hibernating species of bats were significantly lower than those of non-hibernating bats R. leschenaultia and C. sphinx. This observation suggests that bats maintain a basal level of ROS/RNS that does no harm to the brain during hibernation. Results of Western blotting showed that hibernating bats expressed higher amounts of antioxidant proteins than non-hibernating bats and that M. ricketti bats upregulated the expression of some enzymes to overcome oxidative stresses, such as superoxide dismutase, glutathione reductase, and catalase. In contrast, R. ferrumequinum bats maintained a relatively high level of superoxide dismutase 2, glutathione reductase, and thioredoxin-2 throughout the three different states of hibernation cycles. The levels of glutathione (GSH) were higher in M. ricketti bats than in R. ferrumequinum bats and were significantly elevated in R. ferrumequinum bats after torpor. These data suggest that M. ricketti bats use mainly antioxidant enzymes and R. ferrumequinum bats rely on both enzymes and low molecular weight antioxidants (e.g., glutathione) to avoid oxidative stresses during arousal. Furthermore, Nrf2 and FOXOs play major roles in the regulation of antioxidant defenses in the brains of bats during hibernation. Our study revealed strategies used by bats against oxidative

  10. Concepts of oxidative stress and antioxidant defense in Crohn's disease.

    PubMed

    Alzoghaibi, Mohammed A

    2013-10-21

    Oxygen free radical and lipid peroxides (oxidative stress) are highly reactive and represent very damaging compounds. Oxidative stress could be a major contributing factor to the tissue injury and fibrosis that characterize Crohn's disease. An imbalance between increased reactive oxygen species levels and decreased antioxidant defenses occurs in Crohn's patients. Decreased blood levels of vitamins C and E and decreased intestinal mucosal levels of CuZn superoxide dismutase, glutathione, vitamin A, C, E, and β-carotene have been reported for Crohn's patients. Increased levels of proinflammatory cytokines, such as interleukin-1 and -8 and tumor necrosis factor, have been detected in inflammatory bowel disease. Oxidative stress significantly increased the production of neutrophils, chemokines, and interleukin-8. These effects were inhibited by antioxidant vitamins and arachidonic acid metabolite inhibitors in human intestinal smooth muscle cells isolated from the bowels of Crohn's disease patients. The main pathological feature of Crohn's disease is an infiltration of polymorphonuclear neutrophils and mononuclear cells into the affected part of the intestine. Activated neutrophils produce noxious substances that cause inflammation and tissue injury. Due to the physiological and biochemical actions of reactive oxygen species and lipid peroxides, many of the clinical and pathophysiological features of Crohn's disease might be explained by an imbalance of increased reactive oxygen species and a net decrease of antioxidant molecules. This review describes the general concepts of free radical, lipid peroxide and antioxidant activities and eventually illustrates their interferences in the development of Crohn's strictures.

  11. The role of the cellular antioxidant defense in oxidant carcinogenesis.

    PubMed Central

    Cerutti, P; Ghosh, R; Oya, Y; Amstad, P

    1994-01-01

    Oxidant carcinogens interact with multiple cellular targets including membranes, proteins, and nucleic acids. They cause structural damage to DNA and have the potential to mutate cancer-related genes. At the same time, oxidants activate signal transduction pathways and alter the expression of growth- and differentiation-related genes. Indeed, the carcinogenic action of oxidants results from the superposition of these genetic and epigenetic effects. All cells possess elaborate antioxidant defense systems that consist of interacting low and high molecular weight components. Among them, superoxide dismutases (SOD), glutathione peroxidases (GPx), and catalase (CAT) play a central role. Our studies with mouse epidermal cells demonstrate that the balance between several antioxidant enzymes rather than the activity of a single component determines the degree of protection. Unexpectedly, increased levels of Cu,Zn-SOD alone in stable transfectants resulted in sensitization to oxidative chromosomal aberrations and DNA strand breaks. However, a concomitant increase in CAT or GPx in double transfectants corrected or overcorrected the hypersensitivity of the SOD clones depending on the ratios of activities CAT/SOD or GPx/SOD. The cellular antioxidant capacity also affected oxidant induction of the growth-related immediate early protooncogene c-fos. Increases in CAT or SOD reduced the accumulation of c-fos message, albeit for different reasons. The cellular antioxidant defense also affects the action of UVB light (290-320 nm) that represents the most potent carcinogenic wavelength range of the solar spectrum. UVB light is known to exert its action in part through oxidative mechanisms. Increases in CAT and GPx protected mouse epidermal cells from UVB-induced DNA breakage.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 2. PMID:7705286

  12. Do toxic heavy metals affect antioxidant defense mechanisms in humans?

    PubMed

    Wieloch, Monika; Kamiński, Piotr; Ossowska, Anna; Koim-Puchowska, Beata; Stuczyński, Tomasz; Kuligowska-Prusińska, Magdalena; Dymek, Grażyna; Mańkowska, Aneta; Odrowąż-Sypniewska, Grażyna

    2012-04-01

    The aim of this study was to prove whether anthropogenic pollution affects antioxidant defense mechanisms such as superoxide dismutase (SOD) and catalase (CAT) activity, ferritin (FRT) concentration and total antioxidant status (TAS) in human serum. The study area involves polluted and salted environment (Kujawy region; northern-middle Poland) and Tuchola Forestry (unpolluted control area). We investigated 79 blood samples of volunteers from polluted area and 82 from the control in 2008 and 2009. Lead, cadmium and iron concentrations were measured in whole blood by the ICP-MS method. SOD and CAT activities were measured in serum using SOD and CAT Assay Kits by the standardized colorimetric method. Serum TAS was measured spectrophotometrically by the modified Benzie and Strain (1996) method and FRT concentration-by the immunonefelometric method. Pb and Cd levels and SOD activity were higher in volunteers from polluted area as compared with those from the control (0.0236 mg l(-1) vs. 0.014 mg l(-1); 0.0008 mg l(-1) vs. 0.0005 mg l(-1); 0.137 Um l(-1) vs. 0.055 Um l(-1), respectively). Fe level, CAT activity and TAS were lower in serum of volunteers from polluted area (0.442 g l(-1) vs. 0.476 gl(-1); 3.336 nmol min(-1)ml(-1) vs. 6.017 nmol min(-1)ml(-1); 0.731 Trolox-equivalents vs. 0.936 Trolox-equivalents, respectively), whilst differences in FRT concentration were not significant (66.109 μg l(-1) vs. 37.667 μg l(-1), p=0.3972). Positive correlations between Pb (r=0.206), Cd (r=0.602) and SOD in the inhabitants of polluted area, and between Cd and SOD in the control (r=0.639) were shown. In volunteers from both studied environments TAS-FRT (polluted: r=0.625 vs. control: r=0.837) and Fe-FRT (polluted area: r=0.831 vs. control: r=0.407) correlations, and Pb-FRT (r=0.360) and Pb-TAS (r=0.283) in the control were stated. The higher lead and cadmium concentrations in blood cause an increase of SOD activity. It suggests that this is one of the defense mechanisms of an

  13. Reduced enzymatic antioxidative defense in deep-sea fish.

    PubMed

    Janssens, B J; Childress, J J; Baguet, F; Rees, J F

    2000-12-01

    Oxygen, while being an obligate fuel for aerobic life, has been shown to be toxic through its deleterious reactive species, which can cause oxidative stress and lead ultimately to cell and organism death. In marine organisms, reactive oxygen species (ROS), such as the superoxide anion and hydrogen peroxide, are generated within respiring cells and tissues and also by photochemical processes in sea water. Considering both the reduced metabolic rate of nektonic organisms thriving in the deep sea and the physico-chemical conditions of this dark, poorly oxygenated environment, the meso- and bathypelagic waters of the oceans might be considered as refuges against oxidative dangers. This hypothesis prompted us to investigate the activities of the three essential enzymes (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPX) constitutive of the antioxidative arsenal of cells in the tissues of 16 species of meso- and bathypelagic fishes occurring between the surface and a depth of 1300 m. While enzymatic activities were detected in all tissues from all species, the levels of SOD and GPX decreased in parallel with the exponential reduction in the metabolic activity as estimated by citrate synthase activity. In contrast, CAT was affected neither by the metabolic activity nor by the depth of occurrence of the fishes. High levels of metabolic and antioxidative enzymes were detected in the light organs of bioluminescent species. The adjustment of the activity of SOD and GPX to the decreased metabolic activity associated with deep-sea living suggests that these antioxidative defense mechanisms are used primarily against metabolically produced ROS, whereas the maintenance of CAT activity throughout all depths could be indicative of another role. The possible reasons for the occurrence of such a reduced antioxidative arsenal in deep-sea species are discussed.

  14. Erythrocyte Antioxidant Defenses Against Cigarette Smoking in Ischemic Heart Disease

    PubMed Central

    Basalingappa, Doddamani R; Uppala, Satyanarayana; Mitta, Geeta

    2015-01-01

    Background Cigarette smoke promotes atherogenesis by producing oxygen-derived free radicals. Aim The present study was conducted to determine the effect of cigarette smoking on lipid peroxidation and erythrocyte antioxidant status in ischemic heart disease (IHD). Materials and Methods A total of 327 male subjects were enrolled for this study, divided into two groups consisting of 200 patients, who were consecutively admitted for IHD in the intensive cardiac care unit (ICCU) of a Government Hospital and 127 age matched male healthy subjects. Both the groups were subsequently categorised into smokers and non smokers sub groups depending upon the smoking history {>/= 20 pack years of smoking; (20 cigarettes per day for one year constitutes one pack year)}. All 327 subjects were investigated for lipid profile, malondialdehyde (MDA) levels and the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX). Statistical Analysis The differences in the parameters between the groups were tested for significance by one way ANOVA using the SPSS software version 19. A p-value of < 0.001 was considered to be significant statistically. Multiple comparisons were made between all the four groups by Post Hoc Tukey test. Results There was highly significant difference (p<0.001) observed in GPX activity, in comparison to CAT and SOD (p=0.032, p=0.009) between smokers vs non smokers in control group as well as patient group. The plasma MDA levels were found to be increased significantly (p<0.001) in IHD patients, who smoked as compared to those who did not. Conclusion Chronic smoking enhances erythrocyte lipid peroxidation in IHD patients with concomitant failure of both plasma and erythrocyte antioxidant defense mechanisms. Along with conventional lipid markers and plasma MDA levels, the erythrocyte GPX activity was observed to be a better marker of oxidative stress, in chronic smokers, who are at risk of developing IHD. PMID:26266112

  15. Ellagic acid inhibits PKC signaling by improving antioxidant defense system in murine T cell lymphoma.

    PubMed

    Mishra, Sudha; Vinayak, Manjula

    2014-07-01

    Antioxidants protect the cells from the damaging effects of reactive oxygen species (ROS). Production of ROS during cellular metabolism is balanced by their removal by antioxidants. Any condition leading to increased levels of ROS results in oxidative stress, which participates in multistage carcinogenesis by causing oxidative DNA damage, mutations in the proto-oncogenes and tumor suppressor genes. Antioxidant defense system is required to overcome the process of carcinogenesis generated by ROS. Antioxidant enzymes are major contributors to endogenous antioxidant defense system. Protein kinase C (PKC) is generally involved in cell proliferation and its over expression leads to abnormal tumor growth. Out of three classes of PKC, classical PKC is mainly involved in cell proliferation and tumor growth. Classical PKC initiates signaling pathway and leads to activation of a number of downstream protein via activation of NF-κB. Therefore any agent which can promotes the endogenous antioxidant defense system should be able to down regulate PKC and NF-κB activation and thus may be useful in reducing cancer progression. To investigate this hypothesis we have tested the effect of antioxidant ellagic acid on antioxidant enzymes and PKC signaling in Dalton's lymphoma bearing (DL) mice. DL mice were treated with three different doses of ellagic acid. The treatment significantly increases the activity and expression of antioxidant enzymes and down regulates the expression of classical isozymes of PKC as well as the activation of NF-κB, indicating that ellagic acid improves antioxidant defense system and PKC signaling via NF-κB which may contribute to its cancer preventive role.

  16. Antioxidant defense during desiccation of the resurrection plant Haberlea rhodopensis.

    PubMed

    Georgieva, Katya; Dagnon, Soleya; Gesheva, Emiliya; Bojilov, Dimitar; Mihailova, Gergana; Doncheva, Snezhana

    2017-05-01

    Maintaining a strong antioxidant system is essential for preventing drought-induced oxidative stress. Thus, in the present study we investigated the role of some non-enzymic and enzymic antioxidants in desiccation tolerance of Haberlea rhodopensis. The effects of high light upon desiccation on antioxidant capacity was estimated by comparing the response of shade and sun plants. The significant enhancement of the antioxidant capacity at 8% RWC corresponded to an enormous increase in flavonoid content. The important role of ascorbate-glutathione cycle in overcoming oxidative stress during drying of H. rhodopensis was established. The antioxidant capacity increased upon dehydration of both shade and sun plants but some differences in non-enzymatic and enzymatic antioxidants were observed. Investigations on the role of polyphenols in desiccation tolerance are scarce. In the present study the polyphenol profiles (fingerprints) of the resurrection plant Haberlea rhodopensis, including all components of the complex are obtained for the first time. It was clarified that the polyphenol complex of H. rhodopensis includes only two types of glycosides - phenylethanoid glucosides and hispidulin 8-C-glucosides. Upon desiccation the polyphenol content increase and the main role of phenylethanoid glucosides in the protection of H. rhodopensis was revealed.

  17. Recent insights into antioxidant defenses of legume root nodules.

    PubMed

    Becana, Manuel; Matamoros, Manuel A; Udvardi, Michael; Dalton, David A

    2010-12-01

    Legume root nodules are sites of intense biochemical activity and consequently are at high risk of damage as a result of the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). These molecules can potentially give rise to oxidative and nitrosative damage but, when their concentrations are tightly controlled by antioxidant enzymes and metabolites, they also play positive roles as critical components of signal transduction cascades during nodule development and stress. Thus, recent advances in our understanding of ascorbate and (homo)glutathione biosynthesis in plants have opened up the possibility of enhancing N(2) fixation through an increase of their concentrations in nodules. It is now evident that antioxidant proteins other than the ascorbate-glutathione enzymes, such as some isoforms of glutathione peroxidases, thioredoxins, peroxiredoxins, and glutathione S-transferases, are also critical for nodule activity. To avoid cellular damage, nodules are endowed with several mechanisms for sequestration of Fenton-active metals (nicotianamine, phytochelatins, and metallothioneins) and for controlling ROS/RNS bioactivity (hemoglobins). The use of 'omic' technologies has expanded the list of known antioxidants in plants and nodules that participate in ROS/RNS/antioxidant signaling networks, although aspects of developmental variation and subcellular localization of these networks remain to be elucidated. To this end, a critical point will be to define the transcriptional and post-transcriptional regulation of antioxidant proteins.

  18. ALA Inhibits ABA-induced Stomatal Closure via Reducing H2O2 and Ca2+ Levels in Guard Cells

    PubMed Central

    An, Yuyan; Liu, Longbo; Chen, Linghui; Wang, Liangju

    2016-01-01

    5-Aminolevulinic acid (ALA), a newly proved natural plant growth regulator, is well known to improve plant photosynthesis under both normal and stressful conditions. However, its underlying mechanism remains largely unknown. Stomatal closure is one of the major limiting factors for photosynthesis and abscisic acid (ABA) is the most important hormone in provoking stomatal closing. Here, we showed that ALA significantly inhibited ABA-induced stomatal closure using wild-type and ALA-overproducing transgenic Arabidopsis (YHem1). We found that ALA decreased ABA-induced H2O2 and cytosolic Ca2+ accumulation in guard cells with stomatal bioassay, laser-scanning confocal microscopy and pharmacological methods. The inhibitory effect of ALA on ABA-induced stomatal closure was similar to that of AsA (an important reducing substrate for H2O2 removal), CAT (a H2O2-scavenging enzyme), DPI (an inhibitor of the H2O2-generating NADPH oxidase), EGTA (a Ca-chelating agent), and AlCl3 (an inhibitor of calcium channel). Furthermore, ALA inhibited exogenous H2O2- or Ca2+-induced stomatal closure. Taken together, we conclude that ALA inhibits ABA-induced stomatal closure via reducing H2O2, probably by scavenging, and Ca2+ levels in guard cells. Moreover, the inhibitive effect of ALA on ABA-induced stomatal closure was further confirmed in the whole plant. Finally, we demonstrated that ALA inhibits stomatal closing, but significantly improves plant drought tolerance. Our results provide valuable information for the promotion of plant production and development of a sustainable low-carbon society. PMID:27148309

  19. Effects of 30 Days Simulated Weightlessness on Antioxidant Defense System in Rat Liver

    NASA Astrophysics Data System (ADS)

    Wu, Bin; Wu, Ping; Kan, Guang-Han; Liu, Xing-hua; Jiang, Shi-zhong; Sun, Xi-qing; Zhang, Shu

    2008-06-01

    Background The purpose of the present study was to investigate effects of weightlessness included in long-term spaceflight on antioxidant defense system and briefly to evaluate its potent consequences. Method Thirty-two male Sprague-Dawley rats were randomly divided into control, 30 d suspension, 1 d recovery and 7 d recovery group and each group included 8 rats. Lipid peroxidation, contents of antioxidants and activities of antioxidant enzymes in rat liver were measured. Results Compared with control group, hydroperoxide (LOOH) contents showed significantly increased (P<0.05), while glutathione (GSH) and total GSH concentration dramatically decreased (P<0.05 or 0.01) in suspension group and 1 d recovery group. Activities of catalase showed significantly decreased (P<0.05). The relative abundance of mRNA for Cu-Zn superoxide dismutase (Cu-Zn SOD) and GSH-Px was markedly decreased (P<0.05). Conclusion long-term space flight may injure antioxidant defense system and caused oxidative stress and damage. Our study suggested that potent harm to astronauts' health induced by wakened antioxidant defense system should be considered in long-term spaceflight, especially in future trip to Mars.

  20. Enzymatic antioxidant defense in isolated rat hepatocytes exposed to cadmium.

    PubMed

    Skrzycki, M; Czeczot, H; Majewska, M; Podsiad, M; Karlik, W; Grono, D; Wiechetek, M

    2010-01-01

    The aim of the study was the evaluation of cadmium effects on the activity of antioxidant enzymes in rat hepatocytes. The studies were conducted with isolated rat hepatocytes incubated for 1 or 2 hours in a modified (deprived of carbonates with phosphates) Williams' E medium (MWE) in the presence of cadmium chloride (25, 50 and 200 microM). Hepatocytes incubated in the MWE medium without cadmium chloride were used as a control. The application of the modified Williams' E medium allowed for the appearance of cadmium compounds in a soluble form that is indispensable for suitable estimation of its toxic action. There were evaluated markers of the oxidative stress such as: concentration of thiobarbiturate reactive substances (TBARS)--proportional to the level of lipid peroxidation, concentration of reduced glutathione (GSH), and the activity of antioxidant enzymes, including superoxide dismutase (SOD1 and SOD2), catalase (CAT), total glutathione peroxidase (GSHPx), selenium--dependent glutathione peroxidase (SeGSHPx), glutathione transferase (GST) and glutathione reductase (GSHR). Alterations of antioxidant enzymes activity, the level of TBARS and GSH in isolated rat hepatocytes caused by cadmium in vitro, were shown to depend on the concentration and time of exposure of cells to this metal. The increased level of TBARS and GSH was observed as well as changes in the activity of antioxidant enzymes. The activity of SOD isoenzymes and CAT was increased, whereas GSHPx and GST were decreased. These results indicate that cadmium induces oxidative stress followed by alterations in the cellular antioxidant enzyme system in isolated rat hepatocytes.

  1. The growth, photosynthesis and antioxidant defense responses of five vegetable crops to phenanthrene stress.

    PubMed

    Ahammed, Golam Jalal; Wang, Meng-Meng; Zhou, Yan-Hong; Xia, Xiao-Jian; Mao, Wei-Hua; Shi, Kai; Yu, Jing-Quan

    2012-06-01

    Polycyclic aromatic hydrocarbons (PAHs) are global environmental problem. To better understand the growth and physiological responses to atmospheric PAHs, we investigated biomass, photosynthetic machinery and antioxidant system in pakchoi, cucumber, flowering chinese cabbage, tomato and lettuce under various levels of phenanthrene (PHE) stress. Foliar exposure to PHE for 14d resulted in a dose dependent decrease in growth, photosynthesis and chlorophyll contents. With few exceptions, antioxidant enzymes (superoxide dismutase, guaicol peroxidase, catalase, ascorbate peroxidase and glutathione reductase) were upregulated following exposure to PHE. Dose dependent increase in malondialdehyde contents together with H(2)O(2) accumulation suggested an occurrence of oxidative stress following PHE exposure. However, to some extent, growth and antioxidant defense responses differ from species to species. Difference in defense capacity might result in different tolerance and phytotoxicity among the studied vegetables. Taken together, phytotoxicity of PHE to five vegetables could be sequenced in the following order: pakchoi>cucumber>lettuce>tomato>flowering chinese cabbage.

  2. Influence of potent antioxidant leguminosae family plant extracts on growth and antioxidant defense system of Hep2 cancer cell line.

    PubMed

    Spanou, Chrysoula; Stagos, Dimitrios; Aligiannis, Nektarios; Kouretas, Demetrios

    2010-02-01

    Legumes are considered to be a very good source of polyphenolic compounds that may act as chemopreventive agents, especially by their antioxidant properties. However, many of the chemopreventive properties may depend on the concentrations of the phytochemical compounds because potent antioxidant polyphenolic compounds may have pro-oxidant properties and negatively affect cell growth and viability. Thus, the aim of the present study was to assess the possible effect of two potent antioxidant Greek Leguminosae family plant extracts on the growth of a specific cancer cell line and its antioxidant defense cell system. Aqueous extracts of aerial parts of Lathyrus laxiflorus and Phaseolus vulgaris plants were initially examined for their cytotoxicity on the Hep2 cancer cell line at concentrations that possess potent antioxidant properties (100, 400, and 800 microg/mL). After a 24-hour incubation with the extracts, only L. laxiflorus plant extract exhibited the ability to inhibit the cell growth at 400 and 800 microg/mL by 57% and 74%, respectively, whereas P. vulgaris extract had no effect on cell growth at any of the tested concentrations. Noncytotoxic concentrations, 100 microg/mL L. laxiflorus and 800 microg/mL P. vulgaris extract, were used for 2-, 12-, and 24-hour incubation of the cells. The influence of the extracts on the antioxidant defense system of the cells was assessed by measuring the total antioxidant capacity (TAC) of the cells, the catalase (CAT) activity, and the concentrations of reduced glutathione, the oxidized form of glutathione, and thiobarbituric-reactive substances (TBARS) in all times of incubation with the cells. From the results obtained, it seems that only L. laxiflorus extract induces oxidative stress in the cells by reducing TAC and CAT activity and by inducing TBARS, especially with 2 and 12 hours of incubation. P. vulgaris extract reduced only TAC at 2 hours of incubation, indicating also a mild induction of oxidative stress. These

  3. Selenium delays tomato fruit ripening by inhibiting ethylene biosynthesis and enhancing the antioxidant defense system.

    PubMed

    Zhu, Zhu; Chen, Yanli; Shi, Guoqing; Zhang, Xueji

    2017-03-15

    The antioxidant activity of selenium (Se) detoxifies reactive oxygen species (ROS) in plants and animals. In the present study, we elucidated the mechanism underlying Se induced fruit development and ripening. Our study showed that foliar pretreatment with 1mgL(-1) sodium selenate effectively delayed fruit ripening and maintained fruit quality. Gene expression studies revealed that the repression of ethylene biosynthetic genes 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase decreased ethylene production and respiration rate. Moreover, Se treatment probably boosted the antioxidant defense system to reduce ROS generation and membrane damage. The enhanced antioxidative effect was attributed to higher glutathione content and increased activity of enzymes such as glutathione peroxidase and glutathione reductase. The upregulation of respiratory burst oxidase homologue genes in tomato fruit may also contribute to the enhanced antioxidative effect. Selenium treatment represents a promising strategy for delaying ripening and extending the shelf life of tomato fruit.

  4. Reduced antioxidant defense systems in schizophrenia and bipolar I disorder.

    PubMed

    Raffa, Monia; Barhoumi, Sana; Atig, Fatma; Fendri, Chiraz; Kerkeni, Abdelhamid; Mechri, Anwar

    2012-12-03

    Numerous evidence and proofs suggest that the oxidative stress contributes to the pathogenesis of schizophrenia (SZ) and bipolar disorder (BD). The aim of this study is to determine the glutathione levels and the antioxidant enzyme activities in blood samples of patients suffering from SZ and patients with bipolar disorder in comparison with the healthy controlled subjects. It was a case-controlled study carried on upon three groups: forty-six SZ patients (41 men and 5 women, mean age=33.2±7years), thirty BD patients (25 men and 5 women, mean age=31.3±8years) and forty healthy controls (33 men and 7 women, mean age=32.3±7years). The glutathione levels are the total glutathione (GSHt), the reduced glutathione (GSHr), and the oxidized glutathione (GSSG) and the antioxidant enzyme activities that are the superoxide dismutase (SOD), the glutathione peroxidase (GPx), and the catalase (CAT) are determined by the spectrophotometer. We noticed that the GSHt and the GSHr levels significantly decreased in both SZ and BD patients in comparison with the healthy control subjects. As for SOD and CAT activities they remained lower for the patients with SZ when compared both with the controls or the BD patients. We noticed as well that the CAT activity was significantly lower in the BD group than that in the control group, whereas, GPx activity showed no significant change in each group. Hence, this report of the decreased plasma levels of GSHt and GSHr, and the impaired antioxidant enzyme activities in SZ and BD patients aims at highlighting the GSH deficit that seems to be contributing to these disorders, and showing that it may be an important indirect biomarker of the oxidative stress for the SZ and BD.

  5. New fava bean guard cell signaling mutant impaired in ABA-induced stomatal closure.

    PubMed

    Iwai, Sumio; Shimomura, Naoki; Nakashima, Atsushi; Etoh, Takeomi

    2003-09-01

    We isolated a mutant from Vicia faba L. cv. House Ryousai. It wilts easily under strong light and high temperature conditions, suggesting that its stomatal movement may be disturbed. We determined responses of mutant guard cells to some environmental stimuli. Mutant guard cells demonstrated an impaired ability to respond to ABA in 0.1 mM CaCl(2) and stomata did not close in the presence of up to 1 mM ABA, whereas wild-type stomata closed when exposed to 10 micro M ABA. Elevating external Ca(2+) caused a similar degree of stomatal closure in the wild type and the mutant. A high concentration of CO(2) (700 micro l liter(-1)) induced stomatal closure in the wild type, but not in the mutant. On the basis of these results, we propose the working hypothesis that the mutation occurs in the region downstream of CO(2) and ABA sensing and in the region upstream of Ca(2+) elevation. The mutant is named fia (fava bean impaired in ABA-induced stomatal closure).

  6. Antagonistic effect of polyamines on ABA-induced suppression of mitosis in Allium cepa L.

    PubMed

    Mahajan, Arpana; Sharma, Shashi

    2009-02-01

    Effect of abscisic acid (ABA) and polyamines (PAs) [putrescine (Put), spermidine (Spd) and spermine (Spm)] on mitosis in root tips of A. cepa was studied. Treatment with ABA (0.1 to 100 microM) for 24 hr suppressed the mitosis, measured as mitotic index (MI), in a concentration-dependent manner with approx. 50% suppression at 10 microM of ABA. Treatment with different PAs (1 to 100 microM) had differential mitosis suppression effect. Spm was most inhibitory followed by Spd and Put, respectively. The higher concentrations of PAs (1 mM Put; 0.1 and 1 mM Spd or Spm) caused cell distortion. Remarkably, a 24 hr pretreatment of root tips with PAs prior to ABA (100 microM) treatment resulted in a general concentration-dependent reversal of ABA-induced suppression of MI. Catalase (CAT) activity in the root tips, an indicator of redox metabolism, increased due to ABA treatment in a concentration-dependent manner, remained unaltered in response to Put and declined due to Spd and Spm (> or = 0.1 mM). However, all PAs, irrespective of their individual effects, generally antagonized the ABA-dependent increase in CAT activity. Data indicate the possibility of ABA-PA interaction in the regulation of mitosis.

  7. Vitamin E and selenium administration as a modulator of antioxidant defense system: biochemical assessment and modification.

    PubMed

    Noaman, Eman; Zahran, Ahmed M; Kamal, Azza M; Omran, Manar F

    2002-04-01

    Exposure of cells to ionizing radiation leads to the formation of reactive oxygen species (ROS) that are associated with radiation-induced cytotoxicity. Because of the serious damaging potential of ROS, cells depend on the elaboration of the antioxidant defense system (AODS), both enzymatic and nonenzymatic oxidant defense mechanisms. The deficiency in important components of the endogenous AODS leads to the accumulation of oxidative stress inducing oxidative damage. The antioxidant enzymes superoxide dismutase and glutathione peroxidase are key intracellular antioxidants in the metabolism of ROS. In the current study, we investigated the potential role of these antioxidant enzymes in radioresistance during the evaluation of the compensatory role of some exogenous micronutrients against oxidative stress Animals were categorized into eight groups, receiving vitamin E (alpha-tocopherol) and/or selenium (Se) with or without whole-body gamma-irradiation (6.5 Gy). The results indicate that antioxidant pretreatments before irradiation may have some beneficial effects against irradiation-induced injury. The results also indicate that selenium and vitamin E act alone and in an additive fashion as radioprotecting agents. The results further suggest that selenium confers protection in part by inducing or activating cellular free-radical scavenging systems and by enhancing peroxide breakdown, whereas vitamin E appears to confer its protection by an alternate complementary mechanism.

  8. The mtDNA NARP mutation activates the actin-Nrf2 signaling of antioxidant defenses

    SciTech Connect

    Dassa, Emmanuel Philippe; Paupe, Vincent; Goncalves, Sergio; Rustin, Pierre

    2008-04-11

    An efficient handling of superoxides by antioxidant defenses is a crucial issue for cells with respiratory chain deficient mitochondria. We used human cultured skin fibroblasts to delineate the mechanism controlling the expression of antioxidant defenses in the case of a severe ATPase deficiency resulting from an 8993T>G mutation in the mitochondrial ATPase6 gene. We observed the nuclear translocation of the transcription factor Nrf2 associated with thinning of the actin stress fibers. The mobilization of the Nrf2 signaling pathway could be mimicked by a chemical blockade of the ATPase with a specific inhibitor, oligomycin. Interestingly enough, Nrf2 nuclear translocation was not observed in the case of a severe cytochrome oxidase deficiency, indicating that studying the status of this signaling pathway could throw some light on the importance of the oxidative insult associated with different respiratory chain defects.

  9. COMBINED EFFECTS OF CO2 AND O3 ON ANTIOXIDATIVE AND PHOTOPROTECTIVE DEFENSE SYSTEMS IN NEEDLES OF PONDEROSA PINE

    EPA Science Inventory

    To determine interactive effects of important environmental stresses on biochemical defense mechanisms of tree seedlings, we studied responses to elevated O3 and elevated atmospheric CO2 on antioxidative and photoprotective systems in needles of ponderosa pine (Pinus ponderosa Do...

  10. Nuclear-localized AtHSPR links abscisic acid-dependent salt tolerance and antioxidant defense in Arabidopsis.

    PubMed

    Yang, Tao; Zhang, Liang; Hao, Hongyan; Zhang, Peng; Zhu, Haowei; Cheng, Wei; Wang, Yongli; Wang, Xinyu; Wang, Chongying

    2015-12-01

    Salt stress from soil or irrigation water limits plant growth. A T-DNA insertion mutant in C24, named athspr (Arabidopsis thaliana heat shock protein-related), showed several phenotypes, including reduced organ size and enhanced sensitivity to environmental cues. The athspr mutant is severely impaired under salinity levels at which wild-type (WT) plants grow normally. AtHSPR encodes a nuclear-localized protein with ATPase activity, and its expression was enhanced by high salinity and abscisic acid (ABA). Overexpression (OE) of AtHSPR significantly enhanced tolerance to salt stress by increasing the activities of the antioxidant system and by maintaining K(+) /Na(+) homeostasis. Quantitative RT-PCR analyses showed that OE of AtHSPR increased the expression of ABA/stress-responsive, salt overly sensitive (SOS)-related and antioxidant-related genes. In addition, ABA content was reduced in athspr plants with or without salt stress, and exogenous ABA restored WT-like salt tolerance to athspr plants. athspr exhibited increased leaf stomatal density and stomatal index, slower ABA-induced stomatal closure and reduced drought tolerance relative to the WT. AtHSPR OE enhanced drought tolerance by reducing leaf water loss and stomatal aperture. Transcript profiling in athspr showed a differential salt-stress response for genes involved in accumulation of reactive oxygen species (ROS), ABA signaling, cell death, stress response and photosynthesis. Taken together, our results suggested that AtHSPR is involved in salt tolerance in Arabidopsis through modulation of ROS levels, ABA-dependent stomatal closure, photosynthesis and K(+) /Na(+) homeostasis.

  11. Alteration of antioxidant defense status precedes humoral immune response abnormalities in macrosomia

    PubMed Central

    Haddouche, Mustapha; Aribi, Mourad; Moulessehoul, Soraya; Smahi, Mohammed Chems-Eddine Ismet; Lammani, Mohammed; Benyoucef, Mohammed

    2011-01-01

    Summary Background This study aimed to investigate whether the anomalies affecting the antioxidant and humoral immune defenses could start at birth and to check whether the decrease in antioxidant defenses may precede the immune abnormalities in macrosomic newborns. Material/Methods Thirty macrosomic and 30 sex-matched control newborns were recruited for a retrospective case-control study at the Maghnia Maternity Hospital of Tlemcen Department (Algeria). Results The serum IgG levels were similar in both groups. However, plasma ORAC, albumin, vitamin E, SOD, CAT and GSH-Px levels were significantly decreased in macrosomic as compared to control newborns, yet no difference was observed after adjustment for weight. Additionally, serum concentrations of complement C3, MDA and XO were significantly higher in macrosomic as compared to controls before adjustment for weight. Moreover, macrosomia was significantly associated with high levels of complement C3 (OR=8, p=0.002); whereas no association with those of IgG was observed (OR<1, p>0.05). Furthermore, macrosomia was significantly associated with low levels of ORAC (OR=4.96, p=0.027), vitamin E (OR=4.5, p=0.018), SOD (OR=6.88, p=0.020) and CAT (OR=5.67, p=0.017), and with high levels of MDA (OR=10.29, p=0.005). Conclusions Abnormalities of the humoral defense system in excessive weight could be preceded by alterations of the anti-oxidative defense and by inflammatory response and activation of innate immunity at birth. Additionally, excessive weight could be a potential factor contributing to decreased anti-oxidative capacity and increased oxidative stress. PMID:22037745

  12. Daily variations of the antioxidant defense system of the lithodid crab Lithodes santolla.

    PubMed

    Schvezov, Natasha; Lovrich, Gustavo A; Tapella, Federico; Romero, M Carolina

    2013-04-01

    Several physiological processes can induce daily variations in aerobic metabolism. Lithodes santolla is a decapod crustacean of special concern since it is a sub-Antarctic species of commercial interest. The aim of this work was to study in L. santolla the daily variations in levels of enzymatic and non-enzymatic antioxidants, lipid peroxidation and protein oxidation, and haemolymphatic pH. Males of L. santolla of commercial size were randomly dissected every 4 h during a period of 24 h. Enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase and glutathione peroxidase were determined in samples of gills, muscle, hepatopancreas and haemolymph. Ascorbic acid, total glutathione, lipid peroxidation and protein oxidation were also determined in all tissues. Gills showed the highest enzymatic activity and hepatopancreas the highest concentration of non-enzymatic antioxidants. Maximum antioxidant activity was during the dark phase in gills and during the photophase in the haemolymph. Muscle showed significant daily variations, with peaks during the photophase and scotophase. Overall, an antioxidant protective mechanism is present in all tissues, where SOD and CAT represent the first line of defense. The defense mechanism in L. santolla seems to be more active during the dark phase, with slight differences among the analyzed tissues, indicating a higher metabolic rate.

  13. Antioxidant Defenses in Plants with Attention to Prunus and Citrus spp.

    PubMed Central

    Racchi, Milvia Luisa

    2013-01-01

    This short review briefly introduces the formation of reactive oxygen species (ROS) as by-products of oxidation/reduction (redox) reactions, and the ways in which the antioxidant defense machinery is involved directly or indirectly in ROS scavenging. Major antioxidants, both enzymatic and non enzymatic, that protect higher plant cells from oxidative stress damage are described. Biochemical and molecular features of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) are discussed because they play crucial roles in scavenging ROS in the different cell compartments and in response to stress conditions. Among the non enzymatic defenses, particular attention is paid to ascorbic acid, glutathione, flavonoids, carotenoids, and tocopherols. The operation of ROS scavenging systems during the seasonal cycle and specific developmental events, such as fruit ripening and senescence, are discussed in relation to the intense ROS formation during these processes that impact fruit quality. Particular attention is paid to Prunus and Citrus species because of the nutritional and antioxidant properties contained in these commonly consumed fruits. PMID:26784469

  14. Nicotine impact on melanogenesis and antioxidant defense system in HEMn-DP melanocytes.

    PubMed

    Delijewski, Marcin; Wrześniok, Dorota; Otręba, Michał; Beberok, Artur; Rok, Jakub; Buszman, Ewa

    2014-10-01

    Nicotine is a compound of tobacco plants and is responsible for addictive properties of tobacco which is used by about one billion of smokers all over the world. Recently, nicotine has drawn even more attention due to its presumed neuroprotective and antioxidant features as far as common use in various forms of smoking cessation therapies. It is suggested that nicotine may be accumulated in human tissues containing melanin. This may in turn influence biochemical processes in human cells producing melanin. The aim of this study was to examine the impact of nicotine on melanogenesis and antioxidant defense system in cultured normal human melanocytes (HEMn-DP). Nicotine induced concentration-dependent loss in melanocytes viability. The value of EC50 was determined to be 2.52 mM. Nicotine modulated melanin biosynthesis in normal human melanocytes. Significant changes in hydrogen peroxide content and cellular antioxidant enzymes: SOD, CAT, and GPx activities were stated in melanocytes exposed to nicotine, which indicates alterations of antioxidant defense system. The results obtained in vitro may explain a potential influence of nicotine on biochemical processes in melanocytes in vivo during long-term exposition to nicotine.

  15. Balance between Endogenous Superoxide Stress and Antioxidant Defenses

    PubMed Central

    Gort, Amy Strohmeier; Imlay, James A.

    1998-01-01

    Cells devoid of cytosolic superoxide dismutase (SOD) suffer enzyme inactivation, growth deficiencies, and DNA damage. It has been proposed that the scant superoxide (O2−) generated by aerobic metabolism harms even cells that contain abundant SOD. However, this idea has been difficult to test. To determine the amount of O2− that is needed to cause these defects, we modulated the O2− concentration inside Escherichia coli by controlling the expression of SOD. An increase in O2− of more than twofold above wild-type levels substantially diminished the activity of labile dehydratases, an increase in O2− of any more than fourfold measurably impaired growth, and a fivefold increase in O2− sensitized cells to DNA damage. These results indicate that E. coli constitutively synthesizes just enough SOD to defend biomolecules against endogenous O2− so that modest increases in O2− concentration diminish cell fitness. This conclusion is in excellent agreement with quantitative predictions based upon previously determined rates of intracellular O2− production, O2− dismutation, dehydratase inactivation, and enzyme repair. The vulnerability of bacteria to increased intracellular O2− explains the widespread use of superoxide-producing drugs as bactericidal weapons in nature. E. coli responds to such drugs by inducing the SoxRS regulon, which positively regulates synthesis of SOD and other defensive proteins. However, even toxic amounts of endogenous O2− did not activate SoxR, and SoxR activation by paraquat was not at all inhibited by excess SOD. Therefore, in responding to redox-cycling drugs, SoxR senses some signal other than O2−. PMID:9515906

  16. Ferulic acid chronic treatment exerts antidepressant-like effect: role of antioxidant defense system.

    PubMed

    Lenzi, Juliana; Rodrigues, Andre Felipe; Rós, Adriana de Sousa; de Castro, Amanda Blanski; de Castro, Bianca Blanski; de Lima, Daniela Delwing; Magro, Débora Delwing Dal; Zeni, Ana Lúcia Bertarello

    2015-12-01

    Oxidative stress has been claimed a place in pathophysiology of depression; however, the details of the neurobiology of this condition remains incompletely understood. Recently, treatments employing antioxidants have been thoroughly researched. Ferulic acid (FA) is a phenolic compound with antioxidant and antidepressant-like effects. Herein, we investigated the involvement of the antioxidant activity of chronic oral FA treatment in its antidepressant-like effect using the tail suspension test (TST) and the forced swimming test (FST) in mice. The modulation of antioxidant system in blood, hippocampus and cerebral cortex was assessed after stress induction through TST and FST. Our results show that FA at the dose of 1 mg/kg has antidepressant-like effect without affecting locomotor activity. The stress induced by despair tests was able to decrease significantly the activities of superoxide dismutase (SOD) in the blood, catalase (CAT) in the blood and cerebral cortex and glutathione peroxidase (GSH-Px) in the cerebral cortex. Thiobarbituric acid-reactive substances (TBA-RS) levels were increased significantly in the cerebral cortex. Furthermore, the results show that FA was capable to increase SOD, CAT and GSH-Px activities and decrease TBA-RS levels in the blood, hippocampus and cerebral cortex. These findings demonstrated that FA treatment in low doses is capable to exert antidepressant-like effect with the involvement of the antioxidant defense system modulation.

  17. Modulation of antioxidant defense system after long term arsenic exposure in Zantedeschia aethiopica and Anemopsis californica.

    PubMed

    Del-Toro-Sánchez, Carmen Lizette; Zurita, Florentina; Gutiérrez-Lomelí, Melesio; Solis-Sánchez, Brenda; Wence-Chávez, Laura; Rodríguez-Sahagún, Araceli; Castellanos-Hernández, Osvaldo A; Vázquez-Armenta, Gabriela; Siller-López, Fernando

    2013-08-01

    Zantedeschia aethiopica (calla lily) and Anemopsis californica (yerba mansa) are plant species capable of accumulating arsenic (As) and therefore proposed as phytoremediation for removal of As from drinking water. The effects of a continuous 6 month As exposure (34±11 μg/L) from local contaminated groundwater on the antioxidant response of Z. aethiopica and A. californica were evaluated in leaves and stems of the plants bimonthly in a subsurface flow constructed wetland. As increased the activities of the antioxidant enzymes ascorbate peroxidase, glutathione reductase and catalase where higher levels were observed in Z. aethiopica than A. californica. No significant differences were detected on lipid peroxidation levels or antioxidant capacity evaluated by ORAC and DPPH assays or total phenol contents in any part of the plant, although in general the leaves of both plants showed the best antioxidant defense against the metal. In conclusion, Z. aethiopica and A. californica were able to cope to As through induction of a more sensitive enzymatic antioxidant response mechanism.

  18. Inorganic Arsenic Induces NRF2-Regulated Antioxidant Defenses in Both Cerebral Cortex and Hippocampus in Vivo.

    PubMed

    Zhang, Yang; Duan, Xiaoxu; Li, Jinlong; Zhao, Shuo; Li, Wei; Zhao, Lu; Li, Wei; Nie, Huifang; Sun, Guifang; Li, Bing

    2016-08-01

    Inorganic arsenic is reported to induce the reactive oxygen species-mediated oxidative stress, which is supposed to be one of the main mechanisms of arsenic-related neurological diseases. Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of antioxidant defense systems, up-regulates the expression of target genes to fight against oxidative damages caused by harmful substances, including metals. In the present study, mice were used as a model to investigate the oxidative stress levels and the expressions of NRF2-regulated antioxidant substances in both cerebral cortex and hippocampus with 5, 10 and 20 mg/kg NaAsO2 exposure intra-gastrically. Our results showed that acute NaAsO2 treatment resulted in decreased total anti-oxidative capacity (T-AOC) and increased maleic dialdehyde production in the nervous system. We also detected rapidly elevation of NRF2 protein levels by enhancement of Nrf2 transcription, especially at 20 mg/kg NaAsO2 exposure group. In the meantime, mRNA and protein levels of Nrf2 encoding antioxidant enzymes heme oxygenase-1 (HO-1), NAD(P)H: quinine oxidoreductase 1 (NQO1) and glutathione S-transferase (GST) were consistently elevated time- and dose-dependently both in the cerebral cortex and hippocampus. Taken together, the presence study demonstrated the activation of NRF2 pathway, an early antioxidant defensive response, in both cerebral cortex and hippocampus upon inorganic arsenic (iAs) exposure in vivo. A better knowledge on the roles of NRF2 pathway in maintaining cellular redox homeostasis would be helpful for the strategies on improvement of neurotoxicity related to this metalloid.

  19. Antioxidative defense and oxidative stress in ringed seals (Pusa hispida) from differently polluted areas.

    PubMed

    Kanerva, Mirella; Routti, Heli; Tamuz, Yael; Nyman, Madeleine; Nikinmaa, Mikko

    2012-06-15

    High contaminant levels detected in Baltic seals have been associated with various health effects. In this study several parameters related to antioxidative defense and oxidative stress (concentrations of reduced and oxidised glutathione, lipid hydroperoxide and vitamin E, activities of glutathione reductase, peroxidase and S-transferase, glucose-6-phosphate dehydrogenase, catalase, and superoxidedismutase) were measured in the livers of ringed seals from the Baltic Sea and from a less contaminated reference area, Svalbard, Norway. Seals were caught during two different time periods 1996-1997 and 2002-2007, which represent different levels of contamination. No signs of oxidative damage were found in the Baltic seals. However, glutathione metabolism was enhanced in the ringed seals from the Baltic Sea compared to the seals from Svalbard. The adaptation to dive where repetitive ischemia/reperfusion occurs naturally may contribute to the resistance of oxidative stress and to the capacity to increase enzymatic antioxidant defense in phocid seals. This could explain the similarities in oxidative stress levels despite the differences in antioxidant responses between the ringed seals from the Baltic Sea and Svalbard.

  20. Calcium and ZmCCaMK are involved in brassinosteroid-induced antioxidant defense in maize leaves.

    PubMed

    Yan, Jingwei; Guan, Li; Sun, Yue; Zhu, Yuan; Liu, Lei; Lu, Rui; Jiang, Mingyi; Tan, Mingpu; Zhang, Aying

    2015-05-01

    Brassinosteroids (BRs) have been shown to enhance stress tolerance by inducing antioxidant defense systems. However, the mechanisms of BR-induced antioxidant defense in plants remain to be determined. In this study, the role of calcium (Ca(2+)) and maize calcium/calmodulin-dependent protein kinase (CCaMK), ZmCCaMK, in BR-induced antioxidant defense, and the relationship between ZmCCaMK and Ca(2+) in BR signaling were investigated. BR treatment led to a significant increase in cytosolic Ca(2+) concentration in protoplasts from maize mesophyll, and Ca(2+) was shown to be required for BR-induced antioxidant defense. Treatment with BR induced increases in gene expression and enzyme activity of ZmCCaMK in maize leaves. Transient overexpression and silencing of ZmCCaMK in maize protoplasts demonstrated that ZmCCaMK was required for BR-induced antioxidant defense. The requirement for CCaMK was further investigated using a loss-of-function mutant of OsCCaMK, the orthologous gene of ZmCCaMK in rice. Consistent with the findings in maize, BR treatment could not induce antioxidant defense in the rice OsCCAMK mutant. Furthermore, Ca(2+) was required for BR-induced gene expression and activation of ZmCCaMK, while ZmCCaMK was shown to enhance the BR-induced increase in cytosolic Ca(2+) concentration. Moreover, our results also showed that ZmCCaMK and H2O2 influenced each other. These results indicate that Ca(2+) works together with ZmCCaMK in BR-induced antioxidant defense, and there are two positive feedback loops between Ca(2+) or H2O2 and ZmCCaMK in BR signaling in maize.

  1. Photosynthesis in desiccation tolerant plants: energy metabolism and antioxidative stress defense.

    PubMed

    Dinakar, Challabathula; Djilianov, Dimitar; Bartels, Dorothea

    2012-01-01

    Resurrection plants are regarded as excellent models to study the mechanisms associated with desiccation tolerance. During the past years tremendous progress has been made in understanding the phenomenon of desiccation tolerance in resurrection plants, but many questions are open concerning the mechanisms enabling these plants to survive desiccation. The photosynthetic apparatus is very sensitive to reactive oxygen species mediated injury during desiccation and must be maintained or quickly repaired upon rehydration. The photosynthetic apparatus is a primary source of generating reactive oxygen species. The unique ability of plants to withstand the oxidative stress imposed by reactive oxygen species during desiccation depends on the production of antioxidants. The present review considers the overall strategies and the mechanisms involved in the desiccation tolerance in the first part and will focus on the effects on photosynthesis, energy metabolism and antioxidative stress defenses in the second part.

  2. Triiodothyronine and melatonin influence antioxidant defense mechanism in a teleost Anabas testudineus (Bloch): in vitro study.

    PubMed

    Sreejith, P; Beyo, R S; Divya, L; Vijayasree, A S; Manju, M; Oommen, O V

    2007-06-01

    The effect of the hormones triiodothyronine (T3) and melatonin on antioxidant defense system was studied in 6-propyl thiouracil (6-PTU)-treated or photoperiod-exposed teleost Anabas testudineus. 6-PTU (2 microg/g) treatment or photoperiod exposure (24 h) increased malondialdehyde (MDA) and conjugated dienes (CD) concentrations, indicating increased lipid peroxidation (LPO) in the experimental conditions. T3 or melatonin (10(-6) M) treatment for 15 min in vitro in PTU-treated fish reversed the activity of superoxide dismutase (SOD), catalase and glutathione content. T3-treated group showed no change in glutathione peroxidase (GPx) activity, whereas melatonin treatment decreased its activity. T3 inhibited glutathione reductase (GR) activity. Photoperiod exposure (physiological pinealotomy) induced a stressful situation in this teleost, as evidenced by LPO products and antioxidant enzyme activities. Melatonin and T3 treatment for 15 min in vitro also reversed the effect of photoperiod on peroxidation products and the SOD and catalase activities. GR activity decreased in photoperiod-exposed group and melatonin and T3 treatment reversed the activities. The antioxidant enzymes responded to the stress situation after 6-PTU treatment and photoperiod exposure by altering their activities. The study suggested an independent effect of T3 and melatonin on antioxidant defence mechanism in different physiological situations in fish.

  3. Melanogenesis and antioxidant defense system in normal human melanocytes cultured in the presence of chlorpromazine.

    PubMed

    Otreba, Michał; Wrześniok, Dorota; Beberok, Artur; Rok, Jakub; Buszman, Ewa

    2015-02-01

    Chlorpromazine is used in the treatment of schizophrenia and psychotic disorders and belongs to phenothiazine class of neuroleptic drugs. It shows severe side effects such as extrapyramidal symptoms as well as ocular and skin disorders, but the mechanism is still not fully established. The aim of this study was to examine the effect of chlorpromazine on cell viability, melanogenesis and antioxidant defense system in normal human melanocytes. It has been demonstrated that chlorpromazine induces concentration dependent loss in cell viability. The value of EC(50) was calculated to be 2.53 μM. Chlorpromazine in lower concentrations (0.0001, 0.001 and 0.01 μM) increased the melanin and microphthalmia-associated transcription factor (MITF) content and tyrosinase activity, while changes of antioxidant enzymes activity were not observed. It suggests that long-term chlorpromazine therapy, even with low drug doses, may lead to hyperpigmentation disorders in skin and/or eye. The use of the analyzed drug in higher concentrations (0.1 and 1.0 μM) caused significant alterations of antioxidant enzymes activity in normal melanocytes, what may explain a potential role of chlorpromazine in the depletion of cellular antioxidant status leading to other adverse effects associated with the high-dose and/or long-term therapy.

  4. Trichoderma harzianum enhances antioxidant defense of tomato seedlings and resistance to water deficit.

    PubMed

    Mastouri, Fatemeh; Björkman, Thomas; Harman, Gary E

    2012-09-01

    Some plant-symbiotic strains of the genus Trichoderma colonize roots and induce profound changes in plant gene expression that lead to enhanced growth, especially under biotic and abiotic stresses. In this study, we tested the hypothesis that one of the protective mechanisms enhanced by T. harzianum T22 colonization is the antioxidant defense mechanism. Having established that strain T22 modulates the expression of the genes encoding antioxidant enzymes, the status of antioxidant defense of tomato seedlings in response to colonization by T22 and water deficit was investigated. Total ascorbate or glutathione levels were not affected by either stimuli, but under water deficit, antioxidant pools became more oxidized (lower ratios of reduced to oxidized forms), whereas colonized plants maintained redox state as high as or higher than unstressed and untreated plants. The enhanced redox state of colonized plants could be explained by their higher activity of ascorbate and glutathione-recycling enzymes, higher activity of superoxide dismutase, catalase, and ascorbate peroxidase, in both root and shoot throughout the experiment. Similar enzymes were induced in uncolonized plants in response to water-deficit stress but to a lower extent when compared with colonized plants. This orchestrated enhancement in activity of reactive oxygen species (ROS)-scavenging pathways in colonized plants in response to stress supports the hypothesis that enhanced resistance of colonized plants to water deficit is at least partly due to higher capacity to scavenge ROS and recycle oxidized ascorbate and glutathione, a mechanism that is expected to enhance tolerance to abiotic and biotic stresses.

  5. Zinc causes acute impairment of glutathione metabolism followed by coordinated antioxidant defenses amplification in gills of brown mussels Perna perna.

    PubMed

    Trevisan, Rafael; Flesch, Samira; Mattos, Jacó Joaquim; Milani, Márcio Raimundo; Bainy, Afonso Celso Dias; Dafre, Alcir Luiz

    2014-01-01

    Zinc demonstrates protective and antioxidant properties at physiological levels, although these characteristics are not attributed at moderate or high concentrations. Zinc toxicity has been related to a number of factors, including interference with antioxidant defenses. In particular, the inhibition of glutathione reductase (GR) has been suggested as a possible mechanism for acute zinc toxicity in bivalves. The present work investigates the biochemical effects of a non-lethal zinc concentration on antioxidant-related parameters in gills of brown mussels Perna perna exposed for 21 days to 2.6 μM zinc chloride. After 2 days of exposure, zinc caused impairment of the antioxidant system, decreasing GR activity and glutathione levels. An increase in antioxidant defenses became evident at 7 and 21 days of exposure, as an increase in superoxide dismutase and glutathione peroxidase activity along with restoration of glutathione levels and GR activity. After 7 and 21 days, an increase in cellular peroxides and lipid peroxidation end products were also detected, which are indicative of oxidative damage. Changes in GR activity contrasts with protein immunoblotting data, suggesting that zinc produces a long lasting inhibition of GR. Contrary to the general trend in antioxidants, levels of peroxiredoxin 6 decreased after 21 days of exposure. The data presented here support the hypothesis that zinc can impair thiol homeostasis, causes an increase in lipid peroxidation and inhibits GR, imposing a pro-oxidant status, which seems to trigger homeostatic mechanisms leading to a subsequent increase on antioxidant-related defenses.

  6. Preventive role of lens antioxidant defense mechanism against riboflavin-mediated sunlight damaging of lens crystallins.

    PubMed

    Anbaraki, Afrooz; Khoshaman, Kazem; Ghasemi, Younes; Yousefi, Reza

    2016-10-01

    The main components of sunlight reaching the eye lens are UVA and visible light exerting their photo-damaging effects indirectly by the aid of endogenous photosensitizer molecules such as riboflavin (RF). In this study, lens proteins solutions were incubated with RF and exposed to the sunlight. Then, gel mobility shift analysis and different spectroscopic assessments were applied to examine the structural damaging effects of solar radiation on these proteins. Exposure of lens proteins to direct sunlight, in the presence of RF, leads to marked structural crosslinking, oligomerization and proteolytic instability. These structural damages were also accompanied with reduction in the emission fluorescence of Trp and Tyr and appearance of a new absorption peak between 300 and 400nm which can be related to formation of new chromophores. Also, photo-oxidation of lens crystallins increases their oligomeric size distribution as examined by dynamic light scattering analysis. The above mentioned structural insults, as potential sources of sunlight-induced senile cataract and blindness, were significantly attenuated in the presence of ascorbic acid and glutathione which are two important components of lens antioxidant defense system. Therefore, the powerful antioxidant defense mechanism of eye lens is an important barrier against molecular photo-damaging effects of solar radiations during the life span.

  7. Methyl Jasmonate Regulates Antioxidant Defense and Suppresses Arsenic Uptake in Brassica napus L.

    PubMed Central

    Farooq, Muhammad A.; Gill, Rafaqat A.; Islam, Faisal; Ali, Basharat; Liu, Hongbo; Xu, Jianxiang; He, Shuiping; Zhou, Weijun

    2016-01-01

    Methyl jasmonate (MJ) is an important plant growth regulator, involved in plant defense against abiotic stresses, however, its possible function in response to metal stress is poorly understood. In the present study, the effect of MJ on physiological and biochemical changes of the plants exposed to arsenic (As) stress were investigated in two Brassica napus L. cultivars (ZS 758 – a black seed type, and Zheda 622 – a yellow seed type). The As treatment at 200 μM was more phytotoxic, however, its combined application with MJ resulted in significant increase in leaf chlorophyll fluorescence, biomass production and reduced malondialdehyde content compared with As stressed plants. The application of MJ minimized the oxidative stress, as revealed via a lower level of reactive oxygen species (ROS) synthesis (H2O2 and OH-) in leaves and the maintenance of high redox states of glutathione and ascorbate. Enhanced enzymatic activities and gene expression of important antioxidants (SOD, APX, CAT, POD), secondary metabolites (PAL, PPO, CAD) and induction of lypoxygenase gene suggest that MJ plays an effective role in the regulation of multiple transcriptional pathways which were involved in oxidative stress responses. The content of As was higher in yellow seeded plants (cv. Zheda 622) as compared to black seeded plants (ZS 758). The application of MJ significantly reduced the As content in leaves and roots of both cultivars. Findings of the present study reveal that MJ improves ROS scavenging through enhanced antioxidant defense system, secondary metabolite and reduced As contents in both the cultivars. PMID:27148299

  8. THIOCYANATE: A potentially useful therapeutic agent with host defense and antioxidant properties✩

    PubMed Central

    Chandler, Joshua D.; Day, Brian J.

    2014-01-01

    Thiocyanate (SCN) functions in host defense as part of the secreted lactoperoxidase (LPO) microbicidal pathway. SCN is the preferred substrate for LPO-driven catalytic reduction of hydrogen peroxide (H2O2) forming hypothiocyanous acid (HOSCN). HOSCN is selectively generated by many peroxidase enzymes that can utilize SCN including: eosinophil peroxidase (EPO), gastric peroxidase (GPO), myeloperoxidase (MPO), salivary peroxidase (SPO), and thyroid peroxidase (TPO). These enzymes generate HOSCN through a two-electron halogenation reaction. HOSCN is a potent microbicidal agent that kills or nullifies invading pathogens but is better tolerated by host tissue. Some controversy exists as to whether physiologic levels of HOSCN are non-toxic to host tissue, but the disagreement appears to be based on results of enzymatic generation (yielding moderate steady-state exposure) versus direct high level acute exposure in mammalian cell lines. This apparent duality is also true of other endogenous oxidants such as hydrogen peroxide and relates to the difference between physiologically relevant oxidant production versus supra-physiologic bolus dosing approaches. SCN has antioxidant properties that include the ability to protect cells against oxidizing agents such as hypochlorous acid (HOCl) and repair protein chloramines. SCN is an important endogenous molecule that has the potential to interact in complex and elegant ways with its host environment and foreign organisms. SCN’s diverse properties as both host defense and antioxidant agent make it a potentially useful therapeutic. PMID:22968041

  9. Antioxidant Defenses of Francisella tularensis Modulate Macrophage Function and Production of Proinflammatory Cytokines.

    PubMed

    Rabadi, Seham M; Sanchez, Belkys C; Varanat, Mrudula; Ma, Zhuo; Catlett, Sally V; Melendez, Juan Andres; Malik, Meenakshi; Bakshi, Chandra Shekhar

    2016-03-04

    Francisella tularensis, the causative agent of a fatal human disease known as tularemia, has been used in the bioweapon programs of several countries in the past, and now it is considered a potential bioterror agent. Extreme infectivity and virulence of F. tularensis is due to its ability to evade immune detection and to suppress the host's innate immune responses. However, Francisella-encoded factors and mechanisms responsible for causing immune suppression are not completely understood. Macrophages and neutrophils generate reactive oxygen species (ROS)/reactive nitrogen species as a defense mechanism for the clearance of phagocytosed microorganisms. ROS serve a dual role; at high concentrations they act as microbicidal effector molecules that destroy intracellular pathogens, and at low concentrations they serve as secondary signaling messengers that regulate the expression of various inflammatory mediators. We hypothesized that the antioxidant defenses of F. tularensis maintain redox homeostasis in infected macrophages to prevent activation of redox-sensitive signaling components that ultimately result in suppression of pro-inflammatory cytokine production and macrophage microbicidal activity. We demonstrate that antioxidant enzymes of F. tularensis prevent the activation of redox-sensitive MAPK signaling components, NF-κB signaling, and the production of pro-inflammatory cytokines by inhibiting the accumulation of ROS in infected macrophages. We also report that F. tularensis inhibits ROS-dependent autophagy to promote its intramacrophage survival. Collectively, this study reveals novel pathogenic mechanisms adopted by F. tularensis to modulate macrophage innate immune functions to create an environment permissive for its intracellular survival and growth.

  10. Improvement of antioxidant and defense properties of Tomato (var. Pusa Rohini) by application of bioaugmented compost

    PubMed Central

    Verma, Shikha; Sharma, Anamika; Kumar, Raj; Kaur, Charanjit; Arora, Anju; Shah, Raghubir; Nain, Lata

    2014-01-01

    Nutrient management practices play a significant role in improving the nutritional quality of tomato. The present study deals with the evaluation of compost prepared using Effective Microorganisms (EM), on antioxidant and defense enzyme activities of Tomato (Lycopersicon esculentum). A field experiment with five treatments (control, chemical fertilizer and EM compost alone and in combination) was conducted in randomized block design. An increment of 31.83% in tomato yield was recorded with the combined use of EM compost and half recommended dose of chemical fertilizers (N50P30K25 + EM compost at the rate of 5 t ha−1). Similarly, fruit quality was improved in terms of lycopene content (35.52%), antioxidant activity (24–63%) and defense enzymes activity (11–54%), in tomatoes in this treatment as compared to the application of recommended dose of fertilizers. Soil microbiological parameters also exhibited an increase of 7–31% in the enzyme activities in this treatment. Significant correlation among fruit quality parameters with soil microbiological activities reveals the positive impact of EM compost which may be adopted as an eco-friendly strategy for production of high quality edible products. PMID:25972746

  11. Biomarkers of oxidative damage and antioxidant defense capacity in Caiman latirostris blood.

    PubMed

    Poletta, Gisela L; Simoniello, María Fernanda; Mudry, Marta D

    2016-01-01

    Several xenobiotics, and among them pesticides, can produce oxidative stress, providing a mechanistic basis for their observed toxicity. Chronic oxidative stress induces deleterious modifications to DNA, lipids and proteins that are used as effective biomarkers to study pollutant-mediated oxidative stress. No previous report existed on the application of oxidative damage and antioxidant defense biomarkers in Caiman latirostris blood, while few studies reported in other crocodilians were done in organs or muscles of dead animals. The aim of this study was to characterize a new set of oxidative stress biomarkers in C. latirostris blood, through the modification of conventional techniques: 1) damage to lipids by thiobarbituric acid reactive substances (TBARS), 2) damage to DNA by comet assay modified with the enzymes FPG and Endo III, and 3) antioxidant defenses: catalase, superoxide dismutase and glutathione; in order to apply them in future biomonitoring studies. We successfully adapted standard procedures for CAT, SOD, GSH and TBARS determination in C. latirostris blood. Calibration curves for FPG and Endo III showed that the three dilutions tested were appropriate to conduct the modified comet assay for the detection of oxidized bases in C. latirostris erythrocytes. One hour of incubation allowed a complete repair of the damage generated. The incorporation of these biomarkers in biomonitoring studies of caiman populations exposed to xenobiotics is highly important considering that this species has recovered from a serious endangered state through the implementation of sustainable use programs in Argentina, and represents nowadays a relevant economic resource for many human communities.

  12. Responses of antioxidant defenses to Cu and Zn stress in two aquatic fungi.

    PubMed

    Azevedo, Maria-Manuel; Carvalho, Agostinho; Pascoal, Cláudia; Rodrigues, Fernando; Cássio, Fernanda

    2007-05-15

    Aquatic hyphomycetes are fungi that play a key role in plant litter decomposition in streams. Even though these fungi occur in metal-polluted streams, the mechanisms underlying their tolerance to metals are poorly documented. We addressed the effects of Zn and Cu in Varicosporium elodeae and Heliscus submersus by examining metal adsorption to cell walls, plasma membrane integrity and production of reactive oxygen species at metal concentrations inhibiting biomass production in 50% or 80%. The activity of the enzymes catalase, superoxide dismutase and glucose-6-phosphate dehydrogenase was measured to elucidate their role in coping with oxidative stress induced by metals at short- (14 h) and long- (8 days) term exposure. Results show that V. elodeae was more susceptible to the toxic effects induced by Cu and Zn than H. submersus, as indicated by more extensive inhibition of biomass production. Both metals, particularly Cu, induced oxidative stress in the two fungal species, as shown by the noticeable recovery of biomass production in the presence of an antioxidant agent. In both fungi, Cu induced a more severe disruption of plasma membrane integrity than Zn. Our studies on antioxidant defenses showed that catalase had a greater role alleviating stress induced by Zn and Cu than superoxide dismutase. Chronic metal stress also stimulated the production of NADPH, via the pentose phosphate pathway by increasing the activity of glucose-6-phosphate dehydrogenase. Our results suggest that the tolerance of aquatic hyphomycetes to Cu and Zn is associated with the ability of these fungi to initiate an efficient antioxidant defense system.

  13. The variation of antioxidant defense system of Streptomyces sp. M4018 with respect to carbon sources.

    PubMed

    Kayalı, Hulya Ayar; Sazak, Anıl; Sahin, Nevzat; Tarhan, Leman

    2012-01-01

    The effect of glycerol, glucose, and starch as carbon sources on the antioxidant defense system such as superoxide dismutase (SOD) and catalase (CAT) activities, pyruvate levels, and membrane lipid peroxidation (LPO) levels of Streptomyces sp. M4018, after isolation from the rhizosphere samples of Colutea arborescens and identification as a strain of S. hiroshimensis based on phenotypic and genotypic characteristics, were investigated. As an antioxidant defense enzyme, SOD activities increased up to 20 g/L of glycerol and 15 g/L of starch, while they showed negative correlation with glucose concentration. CAT activity variations of glycerol- and glucose-supplemented mediums showed significant positive correlations with the trend of SOD activities. However, CAT activity, in contrast to SOD, in Streptomyces sp. M4018 tended to decrease as the starch concentration increased. The production of pyruvate increased with respect to glycerol and starch up to 15 g/L, while it was positively correlated with glucose concentration. The highest pyruvate production was seen at 20 g/L glucose. Membrane LPO levels were negatively correlated with the activities of SOD and CAT enzymes, and the minimum LPO level was determined at 5 g/L of glucose, where SOD and CAT activities reached their maximum levels. Nevertheless, the higher SOD and CAT activities in a wider range of incubation period compared to the beginning by resulting in insignificant increases in membrane LPO levels showed the unusual antioxidant response capacities of the in Streptomyces sp. M4018 against the potentially deleterious effects of reactive oxygen species (ROS) for glycerol, glucose, and starch as carbon sources.

  14. Exogenous Melatonin Improves Antioxidant Defense in Cucumber Seeds (Cucumis sativus L.) Germinated under Chilling Stress

    PubMed Central

    Marta, Bałabusta; Szafrańska, Katarzyna; Posmyk, Małgorzata M.

    2016-01-01

    The relationship between exogenous melatonin applied into cucumber seeds during osmopriming and modifications of their antioxidant defense was studied. Accumulation of hydrogen peroxide, antioxidant enzyme activities and glutathione pool were investigated in embryonic axes isolated from the control, osmoprimed, and osmoprimed with melatonin seeds. Germinating cucumber seeds are very sensitive to chilling. Temperature 10°C causes oxidative stress in young seedlings. Seed pre-treatment with melatonin seemed to limit H2O2 accumulation during germination under optimal condition as well as during chilling stress and recovery period. Melatonin affected superoxide dismutase (SOD) activity and its isoforms during stress and recovery period but did not influence CAT and POX activities. Thus it is possible that in cucumber this indoleamine could act mostly as a direct H2O2 scavenger, but superoxide anion combat via SOD stimulation. The GSH/GSSG ratio is considered as an indirect determinant of oxidative stress. When the cells are exposed to oxidative stress GSSG is accumulated and the ratio of GSH to GSSG decreases. In our research pre-sowing melatonin application into the cucumber seeds caused high beneficial value of GSH/GSSG ratio that could be helpful for stress countering. Glutathione reductase (GSSG-R) activity in the axes isolated from these seeds was two fold higher than in those isolated from the control and from the osmoprimed without melatonin ones. Additional isoforms of GSSG-R in melatonin treated seeds were also observed. It explains high and effective GSH pool restoration in the seeds pre-treated with melatonin. We confirmed that melatonin could protect cucumber seeds and young seedlings against oxidative stress directly and indirectly detoxifying ROS, thereby plants grown better even in harmful environmental conditions. This work is the first that investigated on plant in vivo model and documented melatonin influence on redox state during seed germination

  15. Compartmentalization of oxidative stress and antioxidant defense in the larval gut of Spodoptera littoralis.

    PubMed

    Krishnan, Natraj; Sehnal, Frantisek

    2006-09-01

    Allelochemicals play important roles in the plant defense against herbivorous insects. They act as feeding deterrents, interfere with digestion and nutrient absorption, and cause production of potentially dangerous oxidative radicals. This study demonstrates that the distributions of oxidative radicals and of the antioxidant enzymes that eliminate them are compartmentalized in the digestive tract of Spodoptera littoralis larvae. Feeding on diets supplemented with the tannic acid (TA), alpha-solanine, and demissidine, respectively, did not affect the rate of food passage through the digestive tract of larvae but 1.25, 2.5, and 5% TA evoked a strong oxidative response. The amount of the superoxide anion in the foregut tissue and content increased up to 70-fold and the titer of total peroxides in the foregut content about 3-fold. This oxidative stress was associated with enhanced carbonyl content in the foregut tissue proteins, indicative of certain tissue deterioration. Extensive foregut damage was probably prevented by elevated activity of the glutathione S-transferase peroxidase. A complex antioxidant response was elicited in the midgut. The activities of superoxide dismutase and catalase increased significantly in the midgut tissue and content, and the activity of ascorbate peroxidase rose in the midgut tissue. The enzymes apparently eliminated oxidative radicals passing to midgut from the foregut with the food bolus and thereby prevented carbonylation of the midgut proteins. We postulate that the generation of oxidative radicals in the foregut and the induction of antioxidant defense in the midgut are controlled processes and that their compartmentalization is an important functional feature of the digestive tract. The glycoalkaloid alpha-solanine and the aglycone demissidine applied at 0.05 and 0.1% concentrations had no effect on any of the examined parameters.

  16. Evaluation of antioxidant defense systems in H4IIE cells infected with a retroviral vector.

    PubMed

    Oh, Soo Jin; Chae, Jooyoung; Zhu, Hongmei; Hien, Tran Thi; Lee, Kiho; Kim, Hwan Mook; Kang, Keon Wook; Song, Gyu Yong; Kang, Jong Seong; Kim, Bong-Hee; Kwon, Kwang-il; Kim, Sang Kyum

    2010-06-01

    Retroviral gene transfer technology is frequently used to establish stable transgenic cell lines. However, no studies to date have evaluated antioxidant defense systems in cells infected with retroviral particles. In the present study, we examined the effects of retroviral infection on antioxidant defense systems using H4IIE cells infected with a retrovirus that overexpresses green fluorescent protein (retro-H4IIE cells). Total oxyradical scavenging capacity and glutathione (GSH), malondialdehyde, and peroxide levels were not significantly altered in retro-H4IIE cells; however, retro-H4IIE cells showed a higher resistance against cytotoxicity, GSH depletion, and malondialdehyde elevation under H(2)O(2)-induced oxidative stress conditions. Immunoblot analysis showed that alpha-class GSH S-transferase (GST) was increased 2.5-fold in retro-H4IIE cells as compared with H4IIE cells; however, catalase, GSH peroxidase-1, peroxiredoxin-1, and thioredoxin-1 remained unaltered or slightly decreased. l-Buthionine-(S,R)-sulfoximine, a GSH synthesis inhibitor, and 1-chloro-2,4-dinitrobenzene, a GST substrate and competitive inhibitor, decreased the difference in H(2)O(2) responses between the two cell types. These results support the hypothesis that the resistance of retro-H4IIE cells to H(2)O(2) can be attributed to an increase in alpha-class GST expression, as levels of GSH and GSH peroxidase-1 were not altered. The present study suggests that antioxidant enzyme expression may change during the establishment of stable transformed cell lines using retroviral techniques.

  17. Compartment-specific antioxidative defense in Arabidopsis against virulent and avirulent Pseudomonas syringae.

    PubMed

    Großkinsky, Dominik K; Koffler, Barbara E; Roitsch, Thomas; Maier, Romana; Zechmann, Bernd

    2012-07-01

    The accumulation of reactive oxygen species (ROS) during biotic stress is either part of a hypersensitive response of the plant or induced directly by the pathogen. Antioxidants such as ascorbate and glutathione counteract the accumulation of ROS and are part of the defense reaction. The aim of the present study was to investigate the compartment-specific importance of ascorbate and glutathione during a virulent and avirulent Pseudomonas syringae infection in Arabidopsis thaliana. Peroxisomes were found to be the hotspot for glutathione accumulation reaching 452% and 258% of control levels 24 h postinoculation during the virulent and avirulent infection, respectively. An accumulation of ascorbate could also be observed in vacuoles during Pseudomonas syringae infection, whereas glutathione remained absent in this cell compartment. Neither glutathione nor ascorbate accumulated in the apoplast during pathogen infection demonstrating an only negligible role of these antioxidants in the apoplast during pathogen infection. Compartment-specific changes followed a recently proposed stress model with an increase of ascorbate and glutathione in most cell compartments at the early stages of infection and a strong drop at the later stage of infection when a strong accumulation of ROS and symptoms occurred in the leaves. This study highlights the importance of certain cell compartments and antioxidants in general for the protection of pathogen-induced ROS accumulation.

  18. Compartment-Specific Antioxidative Defense in Arabidopsis Against Virulent and Avirulent Pseudomonas syringae

    PubMed Central

    Großkinsky, Dominik K.; Koffler, Barbara E.; Roitsch, Thomas; Maier, Romana; Zechmann, Bernd

    2013-01-01

    The accumulation of reactive oxygen species (ROS) during biotic stress is either part of a hypersensitive response of the plant or induced directly by the pathogen. Antioxidants such as ascorbate and glutathione counteract the accumulation of ROS and are part of the defense reaction. The aim of the present study was to investigate the compartment-specific importance of ascorbate and glutathione during a virulent and avirulent Pseudomonas syringae infection in Arabidopsis thaliana. Peroxisomes were found to be the hotspot for glutathione accumulation reaching 452% and 258% of control levels 24 h postinoculation during the virulent and avirulent infection, respectively. An accumulation of ascorbate could also be observed in vacuoles during Pseudomonas syringae infection, whereas glutathione remained absent in this cell compartment. Neither glutathione nor ascorbate accumulated in the apoplast during pathogen infection demonstrating an only negligible role of these antioxidants in the apoplast during pathogen infection. Compartment-specific changes followed a recently proposed stress model with an increase of ascorbate and glutathione in most cell compartments at the early stages of infection and a strong drop at the later stage of infection when a strong accumulation of ROS and symptoms occurred in the leaves. This study highlights the importance of certain cell compartments and antioxidants in general for the protection of pathogen-induced ROS accumulation. PMID:22571419

  19. Antioxidant defense parameters as predictive biomarkers for fermentative capacity of active dried wine yeast.

    PubMed

    Gamero-Sandemetrio, Esther; Gómez-Pastor, Rocío; Matallana, Emilia

    2014-08-01

    The production of active dried yeast (ADY) is a common practice in industry for the maintenance of yeast starters and as a means of long term storage. The process, however, causes multiple cell injuries, with oxidative damage being one of the most important stresses. Consequentially, dehydration tolerance is a highly appreciated property in yeast for ADY production. In this study we analyzed the cellular redox environment in three Saccharomyces cerevisiae wine strains, which show markedly different fermentative capacities after dehydration. To measure/quantify the effect of dehydration on the S. cerevisiae strains, we used: (i) fluorescent probes; (ii) antioxidant enzyme activities; (ii) intracellular damage; (iii) antioxidant metabolites; and (iv) gene expression, to select a minimal set of biochemical parameters capable of predicting desiccation tolerance in wine yeasts. Our results show that naturally enhanced antioxidant defenses prevent oxidative damage after wine yeast biomass dehydration and improve fermentative capacity. Based on these results we chose four easily assayable parameters/biomarkers for the selection of industrial yeast strains of interest for ADY production: trehalose and glutathione levels, and glutathione reductase and catalase enzymatic activities. Yeast strains selected in accordance with this process display high levels of trehalose, low levels of oxidized glutathione, a high induction of glutathione reductase activity, as well as a high basal level and sufficient induction of catalase activity, which are properties inherent in superior ADY strains.

  20. Antioxidant Defense System of Tadpoles (Eupemphix nattereri) Exposed to Changes in Temperature and pH.

    PubMed

    Freitas, Juliane S; Almeida, Eduardo A

    2016-04-01

    Amphibians are highly susceptible to environmental changes, mainly at the larval stage during which they are restricted to small and ephemeral aquatic habitats, which are subject to large fluctuations of abiotic parameters, such as temperature and pH. Consequently, tadpoles experience changes in biochemical, physiological, and molecular processes related to the maintenance of homeostasis, which may lead them to an oxidative stress state. In the present study, we investigated the effects of stress caused by changes in temperature and pH on the antioxidant enzymes catalase (CAT), glucose-6-phosphate dehydrogenase (G6PDH), glutathione reductase (GR) and glutathione-S-transferase (GST) in tadpoles of Eupemphix nattereri. The results show that changes in temperature and pH conditions induce an antioxidant response in tadpoles. GST and GR showed temperature-dependent activities; GST activity was higher in tadpoles exposed to 28°C, whereas GR exhibited increased activity in response to 28°C and 36°C. At 32°C, both GST and GR had the lowest activity. CAT was induced by treatments with acidic (pH 5.0) and alkaline (pH 8.5) pH. Tadpoles exposed to acidic pH also had increased GR activity. The G6PDH was not changed in either experiment. Our data demonstrate that E. nattereri possesses an efficient antioxidant defense system for coping with the damaging effects of heat and acidity/alkalinity conditions in water. The alterations in antioxidant enzymes are probably a result of immediate physiological adaptation of individuals in response to increased production of ROS under environmental stress conditions.

  1. Oxidative stress and antioxidant defenses in two green microalgae exposed to copper.

    PubMed

    Sabatini, Sebastián E; Juárez, Angela B; Eppis, Maria R; Bianchi, Laura; Luquet, Carlos M; Ríos de Molina, María del Carmen

    2009-05-01

    The aim of this work was to assess the effects of 1 week copper exposure (6.2, 108, 210 and 414microM) on Scenedesmus vacuolatus and Chlorella kessleri. The strains showed different susceptibility to copper. Copper content was determined in both strains by total X-ray reflection fluorescence analysis (TXRF). In S. vacuolatus, the increase of medium copper concentration induced an augmentation of protein and MDA content, and a significant decrease in the chlorophyll a/chlorophyll b ratio. S. vacuolatus showed a significant increase of catalase activity in 210 and 414microM of copper, and a significant increment of SOD activity and GSH content only in 414microM of copper. On the contrary, C. kessleri did not show significant differences in these parameters between 6.2 and 108microM of copper. Increased copper in the environment evokes oxidative stress and an increase in the antioxidant defenses of S. vacuolatus.

  2. A Comparative In Silico Study of the Antioxidant Defense Gene Repertoire of Distinct Lifestyle Trypanosomatid Species

    PubMed Central

    Beltrame-Botelho, Ingrid Thaís; Talavera-López, Carlos; Andersson, Björn; Grisard, Edmundo Carlos; Stoco, Patricia Hermes

    2016-01-01

    Kinetoplastids are an ancestral group of protists that contains free-living species and parasites with distinct mechanisms in response to stress. Here, we compared genes involved in antioxidant defense (AD), proposing an evolution model among trypanosomatids. All genes were identified in Bodo saltans, suggesting that AD mechanisms have evolved prior to adaptation for parasitic lifestyles. While most of the monoxenous and dixenous parasites revealed minor differences from B. saltans, the endosymbiont-bearing species have an increased number of genes. The absence of these genes was mainly observed in the extracellular parasites of the genera Phytomonas and Trypanosoma. In trypanosomes, a distinction was observed between stercorarian and salivarian parasites, except for Trypanosoma rangeli. Our analyses indicate that the variability of AD among trypanosomatids at the genomic level is not solely due to the geographical isolation, being mainly related to specific adaptations of their distinct biological cycles within insect vectors and to a parasitism of a wide range of hosts. PMID:27840574

  3. Oxidative stress and antioxidant defense mechanisms linked to exercise during cardiopulmonary and metabolic disorders.

    PubMed

    Fisher-Wellman, Kelsey; Bell, Heather K; Bloomer, Richard J

    2009-01-01

    Oxidative stress has been implicated in the pathophysiology of multiple human diseases, in addition to the aging process. Although various stimuli exist, acute exercise is known to induce a transient increase in reactive oxygen and nitrogen species (RONS), evident by several reports of increased oxidative damage following acute bouts of aerobic and anaerobic exercise. Although the results are somewhat mixed and appear disease dependent, individuals with chronic disease experience an exacerbation in oxidative stress following acute exercise when compared to healthy individuals. However, this increased oxidant stress may serve as a necessary "signal" for the upregulation in antioxidant defenses, thereby providing protection against subsequent exposure to prooxidant environments within susceptible individuals. Here we present studies related to both acute exercise-induced oxidative stress in those with disease, in addition to studies focused on adaptations resulting from increased RONS exposure associated with chronic exercise training in persons with disease.

  4. Endogenous antioxidant defense induction by melon superoxide dismutase reduces cardiac hypertrophy in spontaneously hypertensive rats.

    PubMed

    Carillon, Julie; Rugale, Caroline; Rouanet, Jean-Max; Cristol, Jean-Paul; Lacan, Dominique; Jover, Bernard

    2014-08-01

    We assessed the influence of SODB, a melon superoxide dismutase (SOD), on left ventricular (LV) hypertrophy in SHR. SODB (4 or 40U SOD) was given orally for 4 or 28 days to SHR. For each treatment period, LV weight index (LVWI) and cardiomyocytes size were measured. SOD, glutathione peroxidase (GPx) and catalase expressions, and LV production and presence of superoxide anion were determined. Pro-inflammatory markers were also measured. SODB reduced LVWI and cardiomyocytes size after 4 or 28 days. Cardiac SOD and GPx increased by 30-40% with SODB. The presence but not production of superoxide anion was significantly reduced by SODB. No effect of SODB was detected on inflammatory status in any group. The beneficial effect of SODB on cardiac hypertrophy seems to be related to the stimulation of endogenous antioxidant defense, suggesting that SODB may be of interest as a dietary supplementation during conventional antihypertensive therapy.

  5. Enalapril and captopril enhance glutathione-dependent antioxidant defenses in mouse tissues.

    PubMed

    de Cavanagh, E M; Inserra, F; Ferder, L; Fraga, C G

    2000-03-01

    The effect of enalapril and captopril on total glutathione content (GSSG + GSH) and selenium-dependent glutathione peroxidase (Se-GPx) and glutathione reductase (GSSG-Rd) activities was investigated in mouse tissues. CF-1 mice (4-mo-old females) received water containing enalapril (20 mg/l) or captopril (50 mg/l) for 11 wk. Enalapril increased GSSG + GSH content (P < 0.05) in erythrocytes (147%), brain (112%), and lung (67%), and captopril increased GSSG + GSH content in erythrocytes (190%) and brain (132%). Enalapril enhanced Se-GPx activity in kidney cortex (42%) and kidney medulla (23%) and captopril in kidney cortex (30%). GSSG-Rd activity was enhanced by enalapril in erythrocytes (21%), brain (21%), liver (18%), and kidney cortex (53%) and by captopril in erythrocytes (25%), brain (19%), and liver (34%). In vitro erythrocyte oxidant stress was evaluated by thiobarbituric acid-reactive substances (TBARS) production (control 365 +/- 11, enalapril 221 +/- 26, captopril 206 +/- 17 nmol TBARS x g Hb(-1) x h(-1); both P < 0.05 vs. control) and phenylhydrazine-induced methemoglobin (MetHb) formation (control 66.5 +/- 3.5, enalapril 52.9 +/- 0.4, captopril: 56.4 +/- 2.9 micromol MetHb/g Hb; both P < 0.05 vs. control). Both angiotensin-converting enzyme inhibitor treatments were associated with increased nitric oxide production, as assessed by plasma NO-(3) + NO-(2) level determination (control 9.22 +/- 0.64, enalapril 13.7 +/- 1.9, captopril 17.3 +/- 3.0 micromol NO-(3) + NO-(2)/l plasma; both P < 0.05 vs. control). These findings support our previous reports on the enalapril- and captopril-induced enhancement of endogenous antioxidant defenses and include new data on glutathione-dependent defenses, thus furthering current knowledge on the association of ACE inhibition and antioxidants.

  6. Coordinated Actions of Glyoxalase and Antioxidant Defense Systems in Conferring Abiotic Stress Tolerance in Plants

    PubMed Central

    Hasanuzzaman, Mirza; Nahar, Kamrun; Hossain, Md. Shahadat; Mahmud, Jubayer Al; Rahman, Anisur; Inafuku, Masashi; Oku, Hirosuke; Fujita, Masayuki

    2017-01-01

    Being sessile organisms, plants are frequently exposed to various environmental stresses that cause several physiological disorders and even death. Oxidative stress is one of the common consequences of abiotic stress in plants, which is caused by excess generation of reactive oxygen species (ROS). Sometimes ROS production exceeds the capacity of antioxidant defense systems, which leads to oxidative stress. In line with ROS, plants also produce a high amount of methylglyoxal (MG), which is an α-oxoaldehyde compound, highly reactive, cytotoxic, and produced via different enzymatic and non-enzymatic reactions. This MG can impair cells or cell components and can even destroy DNA or cause mutation. Under stress conditions, MG concentration in plants can be increased 2- to 6-fold compared with normal conditions depending on the plant species. However, plants have a system developed to detoxify this MG consisting of two major enzymes: glyoxalase I (Gly I) and glyoxalase II (Gly II), and hence known as the glyoxalase system. Recently, a novel glyoxalase enzyme, named glyoxalase III (Gly III), has been detected in plants, providing a shorter pathway for MG detoxification, which is also a signpost in the research of abiotic stress tolerance. Glutathione (GSH) acts as a co-factor for this system. Therefore, this system not only detoxifies MG but also plays a role in maintaining GSH homeostasis and subsequent ROS detoxification. Upregulation of both Gly I and Gly II as well as their overexpression in plant species showed enhanced tolerance to various abiotic stresses including salinity, drought, metal toxicity, and extreme temperature. In the past few decades, a considerable amount of reports have indicated that both antioxidant defense and glyoxalase systems have strong interactions in conferring abiotic stress tolerance in plants through the detoxification of ROS and MG. In this review, we will focus on the mechanisms of these interactions and the coordinated action of

  7. The Cryptococcus neoformans catalase gene family and its role in antioxidant defense.

    PubMed

    Giles, Steven S; Stajich, Jason E; Nichols, Connie; Gerrald, Quincy D; Alspaugh, J Andrew; Dietrich, Fred; Perfect, John R

    2006-09-01

    In the present study, we sought to elucidate the contribution of the Cryptococcus neoformans catalase gene family to antioxidant defense. We employed bioinformatics techniques to identify four members of the C. neoformans catalase gene family and created mutants lacking single or multiple catalase genes. Based on a phylogenetic analysis, CAT1 and CAT3 encode putative spore-specific catalases, CAT2 encodes a putative peroxisomal catalase, and CAT4 encodes a putative cytosolic catalase. Only Cat1 exhibited detectable biochemical activity in vitro, and Cat1 activity was constitutive in the yeast form of this organism. Although they were predicted to be important in spores, neither CAT1 nor CAT3 was essential for mating or spore viability. Consistent with previous studies of Saccharomyces cerevisiae, the single (cat1, cat2, cat3, and cat4) and quadruple (cat1 cat2 cat3 cat4) catalase mutant strains exhibited no oxidative-stress phenotypes under conditions in which either exogenous or endogenous levels of reactive oxygen species were elevated. In addition, there were no significant differences in the mean times to mortality between groups of mice infected with C. neoformans catalase mutant strains (the cat1 and cat1 cat2 cat3 cat4 mutants) and those infected with wild-type strain H99. We conclude from the results of this study that C. neoformans possesses a robust antioxidant system, composed of functionally overlapping and compensatory components that provide protection against endogenous and exogenous oxidative stresses.

  8. Long-term consumption of aspartame and brain antioxidant defense status.

    PubMed

    Abhilash, M; Sauganth Paul, M V; Varghese, Mathews V; Nair, R Harikumaran

    2013-04-01

    The present study investigated the effect of long-term intake of aspartame, a widely used artificial sweetener, on antioxidant defense status in the rat brain. Male Wistar rats weighing 150-175 g were randomly divided into three groups as follows: The first group was given aspartame at a dose of 500 mg/kg body weight (b.w.); the second group was given aspartame at dose of 1,000 mg/kg b.w., respectively, in a total volume of 3 mL of water; and the control rats received 3 mL of distilled water. Oral intubations were done in the morning, daily for 180 days. The concentration of reduced glutathione (GSH) and the activity of glutathione reductase (GR) were significantly reduced in the brain of rats that had received the dose of 1,000 mg/kg b.w. of aspartame, whereas only a significant reduction in GSH concentration was observed in the 500-mg/kg b.w. aspartame-treated group. Histopathological examination revealed mild vascular congestion in the 1,000 mg/kg b.w. group of aspartame-treated rats. The results of this experiment indicate that long-term consumption of aspartame leads to an imbalance in the antioxidant/pro-oxidant status in the brain, mainly through the mechanism involving the glutathione-dependent system.

  9. Intracellular oxidant activity, antioxidant enzyme defense system, and cell senescence in fibroblasts with trisomy 21.

    PubMed

    Rodríguez-Sureda, Víctor; Vilches, Ángel; Sánchez, Olga; Audí, Laura; Domínguez, Carmen

    2015-01-01

    Down's syndrome (DS) is characterized by a complex phenotype associated with chronic oxidative stress and mitochondrial dysfunction. Overexpression of genes on chromosome-21 is thought to underlie the pathogenesis of the major phenotypic features of DS, such as premature aging. Using cultured fibroblasts with trisomy 21 (T21F), this study aimed to ascertain whether an imbalance exists in activities, mRNA, and protein expression of the antioxidant enzymes SOD1, SOD2, glutathione-peroxidase, and catalase during the cell replication process in vitro. T21F had high SOD1 expression and activity which led to an interenzymatic imbalance in the antioxidant defense system, accentuated with replicative senescence. Intracellular ROS production and oxidized protein levels were significantly higher in T21F compared with control cells; furthermore, a significant decline in intracellular ATP content was detected in T21F. Cell senescence was found to appear prematurely in DS cells as shown by SA-β-Gal assay and p21 assessment, though not apoptosis, as neither p53 nor the proapoptotic proteins cytochrome c and caspase 9 were altered in T21F. These novel findings would point to a deleterious role of oxidatively modified molecules in early cell senescence of T21F, thereby linking replicative and stress-induced senescence in cultured cells to premature aging in DS.

  10. Antioxidant enzymatic defense in salivary glands of streptozotocin-induced diabetic rats: a temporal study.

    PubMed

    Ibuki, Flavia Kazue; Simões, Alyne; Nogueira, Fernando Neves

    2010-08-01

    Hyperglycemia induces overproduction of superoxide and it is related to diabetic complications. In this study, we analyzed the antioxidant enzymatic defense and the lipid peroxidation of rat salivary glands in six different periods of diabetic condition. Ninety-six rats were divided into 12 groups: C7/14/21/28/45/60 (non-diabetic animals) and D7/14/21/28/45/60 (diabetic animals). Diabetes was induced by streptozotocin and the rats were euthanized after 7, 14, 21, 28, 45, or 60 days. Their parotid (PA) and submandibular (SM) glands were removed soon after the sacrifice and the total protein and malondialdehyde (MDA) concentrations, as well as, the superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities were determined. Twenty-one days after the diabetes induction, the SM glands showed an increase in SOD, CAT, and GPx activities, as well as, MDA concentration. Concerning the PA glands, an increase in the CAT activity and MDA content was observed throughout the observation period. The results suggest that diabetes can cause alterations on the salivary glands and that PA and SM glands react differently when exposed to diabetes condition. However, no impairment of antioxidant system was observed in the group whose diabetic condition had been induced 60 days earlier, herein named 60-day group.

  11. Alleviation of Antioxidant Defense System by Ozonized Olive Oil in DNBS-Induced Colitis in Rats

    PubMed Central

    Bayoumi, Fatehia A.; Ahmed, Naglaa G.

    2014-01-01

    The aim of the study was to evaluate the potential protective effect of ozonized olive oil (OZO) in 2,4-dinitrobenzene sulphuric acid (DNBS) induced colitis in rats and to elucidate the role of some antioxidant defense system (superoxide dismutase “SOD,” glutathione peroxidase “GSH-Px,” and catalase “CAT”) in these effects. The physicochemical parameters including viscosity, peroxide, and acid values of olive oil and OZO were evaluated. The animals were divided into several groups and the colitis was induced in the rats by intracolonic instillation of DNBS at dose of 15 mg/rat. Olive oil (OO) at dose of 6 mg/kg and OZO at doses of 3 and 6 mg/kg was administered orally for 7 days, starting the day before induction of colitis. Our results showed that macroscopic and microscopic damage scores were significantly reduced in a dose response manner in rats pretreated with OZO only. In contrast, CAT, GSH-Px, and SOD activities were significantly increased in the distal colon of inflamed animals pretreated with OZO with respect to control group dose dependently. Results demonstrate that OZO pretreatment exerts protective effects in DNBS induced colitis in rats and provide evidence that the protective effects of OZO are mediated by stimulation of some antioxidant enzymes. PMID:25276059

  12. The relationship between yield and the antioxidant defense system in tomatoes grown under heat stress.

    PubMed

    Rainwater, D T; Gossett, D R; Millhollon, E P; Hanna, H Y; Banks, S W; Lucas, M C

    1996-11-01

    Four putative heat-tolerant tomato (Lycopersicum esculentum) cultivars (Tamasabro, Heat Wave, LHT-24, and Solar Set) and one putative heat-sensitive tomato cultivar (Floradade) were grown in the field under non-stress (average daily temperature of 26 degrees C) and heat-stress (average daily temperature of 34 degrees C) conditions. At anthesis, approximately five weeks after being transplanted to the field, leaf samples were collected for antioxidant analyses. Yield was determined by harvesting ripe fruit seven weeks after the collection of leaf samples. Heat stress resulted in a 79.1% decrease in yield for the heat-sensitive Floradade, while the fruit yield in the heat-tolerant cultivars Heat Wave, LHT-24, Solar Set, and Tamasabro was reduced 51.5%, 22.1%, 43.8%, and 34.8% respectively. When grown under heat stress, antioxidant activities were also greater in the heat-tolerant cultivars. Superoxide dismutase (SOD) activity increased up to 9-fold in the heat-tolerant cultivars but decreased 83.1% in the heat-sensitive Floradade. Catalase, peroxidase, and ascorbate peroxidase activity increased significantly in all cultivars. Only Heat Wave showed a significant increase in glutathione reductase in response to heat stress but all heat-tolerant cultivars exhibited significantly lower oxidized ascorbate/reduced ascorbate ratios, greater reduced glutathione/oxidized glutathione rations, and greater alpha-tocopherol concentrations compared to the heat-sensitive cultivar Floridade. These data indicate that the more heat-tolerant cultivars had an enhanced capacity for scavenging active oxygen species and a more active ascorbate-glutathione cycle and suggest a strong correlation between the ability to up-regulate the antioxidant defense system and the ability of tomatoes to produce greater yields when grown under heat stress.

  13. Photosynthesis and antioxidant defense system of Gynura Bicolor DC grown at different elevated CO2 levels

    NASA Astrophysics Data System (ADS)

    Wang, Minjuan; Liu, Hong; Fu, Yuming

    Atmospheric carbon dioxide concentration [CO _{2}] will increase in the future and will affect global climate and ecosystem productivity. However, this is not clearly an area that requires further study on the most appropriate [CO _{2}] selection for plant growth and quality in a closed, controlled environment. The aim of this study was to determine the variation of photosynthetic characteristics and antioxidant status under five CO _{2} concentration (400, 800, 1200, 2000 and 3000 umol mol (-1) ) on the leaf of Gynura bicolor DC. Here the results show that net photosynthetic rate(Pn), Chl content, edible biomass(EB), leaf blade width(LBW), root weight(RW), fructose(Fru) and sucrose(Suc) of Gynura bicolor DC increased under elevated [CO _{2}] of 800 umol mol (-1) , 1200 umol mol (-1) and 2000 umol mol (-1) . On the contrary, photosynthesis and biomass production declined significantly at 3000 umol mol (-1) CO _{2}, While Lipid peroxidation (LPO), malondialdehyde (MDA) and hydrogen peroxide (H _{2}O _{2}) achieved the highest levels. Furthermore, the contents of glutathione (GSH), vitamin C (VC), and vitamin E (VE), and total antioxidant capacity (T-AOC), the activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) reached the highest level at 2000 umol mol ({-1) }CO _{2}. Results imply that a significant increase in growth and antioxidant defense system of Gynura bicolor DC occurred under 800-2000 umol mol (-1) of CO _{2} concentration provided a theoretical basis for the application for plants selection in Bioregeneration Life Support System (BLSS) and a closed controlled environment.

  14. Antioxidant defenses in caterpillars: role of the ascorbate-recycling system in the midgut lumen.

    PubMed

    Barbehenn, R V; Bumgarner, S L; Roosen, E F; Martin, M M

    2001-04-01

    This study demonstrates that an ascorbate-recycling system in the midgut lumen can act as an effective antioxidant defense in caterpillars that feed on prooxidant-rich foods. In tannin-sensitive larvae of the forest tent caterpillar, Malacosoma disstria (Lasiocampidae), ingested tannic acid is oxidized in the midgut lumen, generating significant quantities of peroxides, including hydrogen peroxide, which readily diffuses across cell membranes and is a powerful cytotoxin. By contrast, in the tannin-tolerant larvae of the white-marked tussock moth, Orgyia leucostigma (Lymantriidae), tannic acid oxidation and the generation of peroxides are suppressed. The superior defense of O. leucostigma against oxidative stress imposed by the oxidation of ingested polyphenols can be explained by the presence of higher concentrations of ascorbate and glutathione in the midgut lumen. In O. leucostigma at least 50% of the ingested ascorbate present in the anterior midgut is still present in the posterior midgut, whereas in M. disstria, only 10% of the ascorbate is present in the posterior half of the midgut. We propose that the maintenance of higher levels of ascorbate in the midgut lumen of O. leucostigma than in M. disstria is explained by the secretion of glutathione into the midgut lumen by O. leucostigma, thereby forming a complete ascorbate-recycling system. The concentration of glutathione in the midgut lumen of O. leucostigma is 3.5-fold higher than in M. disstria and more than double the concentration in the diet. Our results emphasize the importance of a defensive strategy in herbivorous insects based on the maintenance of conditions in the gut lumen that reduce or eliminate the potential prooxidant behavior of ingested phenols.

  15. Antioxidant defense gene analysis in Brassica oleracea and Trifolium repens exposed to Cd and/or Pb.

    PubMed

    Bernard, F; Dumez, S; Brulle, F; Lemière, S; Platel, A; Nesslany, F; Cuny, D; Deram, A; Vandenbulcke, F

    2016-02-01

    This study focused on the expression analysis of antioxidant defense genes in Brassica oleracea and in Trifolium repens. Plants were exposed for 3, 10, and 56 days in microcosms to a field-collected suburban soil spiked by low concentrations of cadmium and/or lead. In both species, metal accumulations and expression levels of genes encoding proteins involved and/or related to antioxidant defense systems (glutathione transferases, peroxidases, catalases, metallothioneins) were quantified in leaves in order to better understand the detoxification processes involved following exposure to metals. It appeared that strongest gene expression variations in T. repens were observed when plants are exposed to Cd (metallothionein and ascorbate peroxidase upregulations) whereas strongest variations in B. oleracea were observed in case of Cd/Pb co-exposures (metallothionein, glutathione transferase, and peroxidase upregulations). Results also suggest that there is a benefit to use complementary species in order to better apprehend the biological effects in ecotoxicology.

  16. Does consumption of two portions of salmon per week enhance the antioxidant defense system in pregnant women?

    PubMed

    García-Rodríguez, Cruz E; Mesa, María D; Olza, Josune; Vlachava, Maria; Kremmyda, Lefkothea-Stella; Diaper, Norma D; Noakes, Paul S; Miles, Elizabeth A; Ramírez-Tortosa, María Carmen; Liaset, Bjørn; Frøyland, Livar; Rossary, Adrien; Farges, Marie-Chantal; Vasson, Marie-Paule; Aguilera, Concepcion M; Helmersson-Karlqvist, Johanna; Godfrey, Keith M; Calder, Philip C; Basu, Samar; Gil, Angel

    2012-06-15

    Salmon is a rich source of marine n-3 fatty acids, which may increase oxidative stress and, in turn, could affect the antioxidant defense system in blood plasma and erythrocytes of pregnant women. The Salmon in Pregnancy Study provided two meals of salmon per week to pregnant women from week 20 of gestation; the control group maintained their habitual diet low in oily fish. Higher selenium and retinol plasma concentrations were observed after dietary salmon supplementation. Besides, a concomitant increase in selenium and glutathione concentration as well as glutathione peroxidase and reductase activities were detected as pregnancy progressed. However, tocopherols, retinol, β-carotene, and coenzyme Q(10) decreased in late pregnancy. Collectively, our findings lead to the hypothesis that increased farmed salmon intake may increase antioxidant defenses during pregnancy. Clinical trials identifier NCT00801502.

  17. Potassium contributes to zinc stress tolerance in peach (Prunus persica) seedlings by enhancing photosynthesis and the antioxidant defense system.

    PubMed

    Song, Z Z; Duan, C L; Guo, S L; Yang, Y; Feng, Y F; Ma, R J; Yu, M L

    2015-07-27

    Zinc (Zn) is considered to be a major industrial pollutant because excessive amounts can impair plant growth. In this paper, we found that peach 'Yoshihime' seedlings are promising Zn tolerant plants. However, heavy Zn toxicity (2 mM) damaged plant performance by disrupting biochemical processes, including photosynthesis, proline production, and K(+) nutrition. Notably, elevated external K(+) supply (10 mM) alleviated peach seedlings from Zn toxicity, evidenced by enhanced photosynthesis, antioxidant defense systems, and plant K(+) nutritional status. Moreover, the transcript levels of KUP (K(+) uptake) genes involved in K(+) acquisition, transport, and homeostasis were significantly upregulated following supply of sufficient K(+) upon Zn toxicity. In general, K(+) favorably contributes to improvements in internal K(+) homeostasis, via the help of K(+) transporters, further protecting plant photosynthesis and the antioxidative defense system. Our findings further benefit the study of the mechanisms underpinning heavy metal tolerance in woody plants.

  18. Purple potato (Solanum tuberosum L.) anthocyanins attenuate alcohol-induced hepatic injury by enhancing antioxidant defense.

    PubMed

    Jiang, Zhihui; Chen, Chen; Wang, Jian; Xie, Wenyan; Wang, Meng; Li, Xinsheng; Zhang, Xiaoying

    2016-01-01

    Alcoholic liver disease (ALD) is a serious and challenging health issue. In the past decade, natural components possessing hepatoprotective properties have gained more attention for ALD intervention. In this study, the phytochemical components of anthocyanins from purple potato were assessed using UPLC-MS/MS, and the hepatoprotective effects of purple potato anthocyanins (PPAs) were investigated in the ALD mouse model. Serum and liver biochemical parameters were determined, along with histopathological changes in liver tissue. In addition, the major contributors to alcohol-induced oxidative stress were assessed. The results indicated that the levels of aspartate transaminase and alanine transaminase were lower in the serum of the PPA-treated group than the alcohol-treated group. PPAs significantly inhibited the reduction of total cholesterol and triglycerides. Higher levels of superoxide dismutase and reduced glutathione enzymes as well as a reduction in the formation of malondialdehyde occurred in mice fed with PPAs. In addition, PPAs protected against increased alcohol-induced levels and activity of cytochrome P450 2E1 (CYP2E1), which demonstrates the effects of PPAs against alcohol-induced oxidative stress and liver injury. This study suggests that PPAs could be an effective therapeutic agent in alcohol-induced liver injuries by inhibiting CYP2E1 expression and thereby strengthening antioxidant defenses.

  19. Enhanced antioxidant defense due to extracellular catalase activity in Syrian hamster during arousal from hibernation.

    PubMed

    Ohta, Hitomi; Okamoto, Iwao; Hanaya, Toshiharu; Arai, Shigeyuki; Ohta, Tsunetaka; Fukuda, Shigeharu

    2006-08-01

    Mammalian hibernators are considered a natural model for resistance to ischemia-reperfusion injuries, and protective mechanisms against oxidative stress evoked by repeated hibernation-arousal cycles in these animals are increasingly the focus of experimental investigation. Here we show that extracellular catalase activity provides protection against oxidative stress during arousal from hibernation in Syrian hamster. To examine the serum antioxidant defense system, we first assessed the hibernation-arousal state-dependent change in serum attenuation of cytotoxicity induced by hydrogen peroxide. Serum obtained from hamsters during arousal from hibernation at a rectal temperature of 32 degrees C, concomitant with the period of increased oxidative stress, attenuated the cytotoxicity four-fold more effectively than serum from cenothermic control hamsters. Serum catalase activity significantly increased during arousal, whereas glutathione peroxidase activity decreased by 50%, compared with cenothermic controls. The cytoprotective effect of purified catalase at the concentration found in serum was also confirmed in a hydrogen peroxide-induced cytotoxicity model. Moreover, inhibition of catalase by aminotriazole led to an 80% loss of serum hydrogen peroxide scavenging activity. These results suggest that extracellular catalase is effective for protecting hibernators from oxidative stress evoked by arousal from hibernation.

  20. Low Concentrations of Hydrogen Peroxide Activate the Antioxidant Defense System in Human Sperm Cells.

    PubMed

    Evdokimov, V V; Barinova, K V; Turovetskii, V B; Muronetz, V I; Schmalhausen, E V

    2015-09-01

    The effect of low concentrations of hydrogen peroxide (10-100 µM) on sperm motility and on the activity of the sperm enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDS) was investigated. Incubation of semen samples with 10 and 100 µM hydrogen peroxide increased the content of spermatozoa with progressive motility by 20 and 18%, respectively, and enhanced the activity of GAPDS in the sperm cells by 27 and 20% compared to a semen sample incubated without additions. It was also found that incubation with 10 µM hydrogen peroxide increased the content of reduced glutathione (GSH) in sperm cells by 50% on average compared to that in the control samples. It is supposed that low concentrations of hydrogen peroxide activate the pentose phosphate pathway, resulting in NADPH synthesis and the reduction of the oxidized glutathione by glutathione reductase yielding GSH. The formed GSH reduces the oxidized cysteine residues of the GAPDS active site, increasing the activity of the enzyme, which in turn enhances the content of sperm cells with progressive motility. Thus, the increase in motile spermatozoa in the presence of low concentrations of hydrogen peroxide can serve as an indicator of normal functioning of the antioxidant defense system in sperm cells.

  1. Pterostilbene Decreases the Antioxidant Defenses of Aggressive Cancer Cells In Vivo: A Physiological Glucocorticoids- and Nrf2-Dependent Mechanism

    PubMed Central

    Benlloch, María; Obrador, Elena; Valles, Soraya L.; Rodriguez, María L.; Sirerol, J. Antoni; Alcácer, Javier; Pellicer, José A.; Salvador, Rosario; Cerdá, Concha; Sáez, Guillermo T.

    2016-01-01

    Abstract Aims: Polyphenolic phytochemicals have anticancer properties. However, in mechanistic studies, lack of correlation with the bioavailable concentrations is a critical issue. Some reports had suggested that these molecules downregulate the stress response, which may affect growth and the antioxidant protection of malignant cells. Initially, we studied this potential underlying mechanism using different human melanomas (with genetic backgrounds correlating with most melanomas), growing in nude mice as xenografts, and pterostilbene (Pter, a natural dimethoxylated analog of resveratrol). Results: Intravenous administration of Pter decreased human melanoma growth in vivo. However, Pter, at levels measured within the tumors, did not affect melanoma growth in vitro. Pter inhibited pituitary production of the adrenocorticotropin hormone (ACTH), decreased plasma levels of corticosterone, and thereby downregulated the glucocorticoid receptor- and nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-dependent antioxidant defense system in growing melanomas. Exogenous corticosterone or genetically induced Nrf2 overexpression in melanoma cells prevented the inhibition of tumor growth and decreased antioxidant defenses in these malignant cells. These effects and mechanisms were also found in mice bearing different human pancreatic cancers. Glutathione depletion (selected as an antimelanoma strategy) facilitated the complete elimination by chemotherapy of melanoma cells isolated from mice treated with Pter. Innovation: Although bioavailability-related limitations may preclude direct anticancer effects in vivo, natural polyphenols may also interfere with the growth and defense of cancer cells by downregulating the pituitary gland-dependent ACTH synthesis. Conclusions: Pter downregulates glucocorticoid production, thus decreasing the glucocorticoid receptor and Nrf2-dependent signaling/transcription and the antioxidant protection of melanoma and pancreatic cancer cells

  2. Gene expression profile of oxidative stress and antioxidant defense in lung tissue of patients exposed to sulfur mustard.

    PubMed

    Tahmasbpour, Eisa; Ghanei, Mostafa; Qazvini, Ali; Vahedi, Ensieh; Panahi, Yunes

    2016-04-01

    Sulfur mustard (SM) is a potent alkylating agent that targets several organs, especially lung tissue. Although pathological effects of SM on mustard lung have been widely considered, molecular and cellular mechanisms for these pathologies are poorly understood. We investigated changes in expression of genes related to oxidative stress (OS) and antioxidant defense caused by SM in lung tissue of patients. We performed gene expression profiling of OS and antioxidant defense in lung tissue samples from healthy controls (n=5) and SM-exposed patients (n=6). Changes in gene expression were measured using a 96-well RT(2) Profiler ™PCR Array: Human Oxidative Stress and Antioxidant Defense, which arrayed 84 genes functionally involved in cellular OS response. 47 (55.95%) genes were found to be significantly upregulated in patients with mustard lung compared with controls (p<0.05), whereas 7 (8.33%) genes were significantly downregulated (p<0.05). Among the most upregulated genes were OS responsive-1 (OXSR1), forkhead box M1 (FOXM1), and glutathione peroxidase-2 (GPX2), while metallothionein-3 (MT3) and glutathione reductase (GSR) were the most downregulated genes. Expression of hypoxia-induced genes (CYGB and MB), antioxidants and reactive oxygen species (ROS)-producing genes were significantly altered, suggesting an increased oxidative damage in mustard lungs. Mustard lungs were characterized by hypoxia, massive production of ROS, OS, disruption of epithelial cells, surfactant dysfunction, as well as increased risk of lung cancer and pulmonary fibrosis. Oxidative stress induced by ROS is the major mechanism for direct effect of SM exposure on respiratory system. Antioxidant treatment may improve the main features of mustard lungs.

  3. Expression of genes involved in redox homeostasis and antioxidant defense in a marine macroalga Ulva fasciata by excess copper.

    PubMed

    Wu, Tsung-Meng; Hsu, Yuan-Ting; Sung, Ming-Shiuan; Hsu, Yi-Ting; Lee, Tse-Min

    2009-10-04

    The expression of genes involved in the control of redox homeostasis and antioxidant defense was studied in macroalga Ulva fasciata Delile in response to 5 and 50 microM CuSO(4). Redox-related genes, methionine sulfoxide reductase A (UfMsrA), thioredoxin (UfTrx), cyclophilin (UfCyp), and ferritin (UfFer) that were up-regulated by excess Cu [Wu, T.M., Lee, T.M., 2008. Regulation of activity and gene expression of antioxidant enzymes in Ulva fasciata Delile (Ulvales, Chlorophyta) in response to excess copper. Phycologia 47, 346-360] were cloned and their expression was compared to superoxide dismutase (UfMnsod and UfFesod), ascorbate peroxidase (UfApx), glutathione reductase (UfGr), and catalase (UfCat). Transcripts of UfMsrA, UfCyp, and UfFer were increased by excess Cu with a peak at 3h and that of UfTrx increased after 6-9h, but not affected by 4-day exposure to excess Cu, except an increase in UfMsrA transcript. Transcripts of UfMnsod, UfFesod, UfApx, UfGr and UfCat can be increased by 4-day exposure to Cu excess [Wu, T.M., Lee, T.M., 2008. Regulation of activity and gene expression of antioxidant enzymes in Ulva fasciata Delile (Ulvales, Chlorophyta) in response to excess copper. Phycologia 47, 346-360] but not by short-term excess Cu treatment, except UfGr whose transcript increased after 3h. Reactive oxygen species involved in up-regulation of antioxidant defense enzymes genes. These results suggest that the expression of genes of antioxidant defense enzymes and UfMsrA are associated with long-term adaptation of U. fasciata to Cu excess and transcription of redox-related genes and UfGr is up-regulated for short-term acclimation.

  4. Effect of vitamin E and C supplements on antioxidant defense system in cardiovascular disease patients in Zahedan, southeast Iran.

    PubMed

    Karajibani, Mansour; Hashemi, Mohammad; Montazerifar, Farzaneh; Dikshit, Madhurima

    2010-01-01

    Oxidative stress plays an important role in the pathogenesis of cardiovascular disease (CVD). Growing evidence suggest that antioxidant vitamins might reduce the risk of disease outcomes by their ability to scavenge free radicals. The aim of the present study was to evaluate the supplementation of vitamins E and C on oxidant and antioxidant status in CVD patients. We conducted a case-control study with vitamin E (400 IU/d) and vitamin C (500 mg/d) supplementation in 40 CVD patients for 2 mo. Antioxidant (enzymatic and non-enzymatic) and oxidant status were analyzed pre and post supplementation. In the initial stage the activity of both enzymatic and non-enzymatic antioxidants were lower, while the malondialdehyde (MDA) level was elevated (p<0.0001). After intervention, a significant increase in superoxide dismutase (SOD) activity (61.7%), glutathione peroxidase (GPx) activity (59.3%), the levels of vitamin E (83.7%), C (145.3%), total antioxidant capacity (TAC) (62.8%) and a significant decrease in MDA (40%) value were observed (p<0.0001). There was a significant negative correlation between MDA and TAC. The results suggest that supplementation with a combination of vitamins E and C reduced lipid peroxidation and strengthened the antioxidant defense system. Hence, there will be beneficial effects on the heart by reducing oxidative stress in CVD patients.

  5. Seasonal Variations of the Activity of Antioxidant Defense Enzymes in the Red Mullet (Mullus barbatus l.) from the Adriatic Sea

    PubMed Central

    Pavlović, Sladjan Z.; Borković Mitić, Slavica S.; Radovanović, Tijana B.; Perendija, Branka R.; Despotović, Svetlana G.; Gavrić, Jelena P.; Saičić, Zorica S.

    2010-01-01

    This study investigated seasonal variations of antioxidant defense enzyme activities: total, manganese, copper zinc containing superoxide dismutase (Tot SOD, Mn SOD, CuZn SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and biotransformation phase II enzyme glutathione-S-transferase (GST) activity in the liver and white muscle of red mullet (Mullus barbatus). The investigations were performed in winter and spring at two localities: Near Bar (NB) and Estuary of the River Bojana (EB) in the Southern Adriatic Sea. At both sites, Mn SOD, GSH-Px, GR and GST activities decreased in the liver in spring. In the white muscle, activities of Mn SOD, GSH-Px, GR and GST in NB decreased in spring. GR decreased in spring in EB, while CAT activity was higher in spring at both sites. The results of Principal Component Analysis (PCA) based on correlations indicated a clear separation of various sampling periods for both investigated tissues and a marked difference between two seasons. Our study is the first report on antioxidant defense enzyme activities in the red mullet in the Southern Adriatic Sea. It indicates that seasonal variations of antioxidant defense enzyme activities should be used in further biomonitoring studies in fish species. PMID:20411106

  6. Effect of magnetic fields on antioxidative defense and fitness-related traits of Baculum extradentatum (insecta, phasmatodea).

    PubMed

    Todorović, Dajana; Mirčić, Dejan; Ilijin, Larisa; Mrdaković, Marija; Vlahović, Milena; Prolić, Zlatko; Mataruga, Vesna Perić

    2012-04-01

    This study aimed to determine the effect of magnetic fields on the antioxidative defense and fitness-related traits of Baculum extradentatum. Following exposure to magnetic fields, antioxidative defense (superoxide dismutase (SOD), catalase (CAT) activities, and total glutathione (GSH) content) and fitness-related traits (egg mortality, development dynamics, and mass of nymphs) were monitored in nymphs. The experimental groups were: control (kept out of influence of the magnets), a group exposed to a constant magnetic field (CMF) of 50 mT, and a group exposed to an alternating magnetic field (AMF) of 50 Hz, 6 mT. We found increased SOD and CAT activities in animals exposed to constant and AMFs, whereas GSH activity was not influenced by experimental magnetic fields. No differences were found in egg mortality between control and experimental groups. Significant differences in the time of development between the control and the CMF group were observed, as well as between the CMF and the AMF group. No differences were found in the mass of the nymphs between the three experimental groups. In conclusion, CMF and AMF have the possibility to modulate the antioxidative defense and some of the fitness-related traits in B. extradentatum.

  7. Seasonal variations of the activity of antioxidant defense enzymes in the red mullet (Mullus barbatus l.) from the Adriatic Sea.

    PubMed

    Pavlović, Sladjan Z; Borković Mitić, Slavica S; Radovanović, Tijana B; Perendija, Branka R; Despotović, Svetlana G; Gavrić, Jelena P; Saicić, Zorica S

    2010-02-26

    This study investigated seasonal variations of antioxidant defense enzyme activities: total, manganese, copper zinc containing superoxide dismutase (Tot SOD, Mn SOD, CuZn SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and biotransformation phase II enzyme glutathione-S-transferase (GST) activity in the liver and white muscle of red mullet (Mullus barbatus). The investigations were performed in winter and spring at two localities: Near Bar (NB) and Estuary of the River Bojana (EB) in the Southern Adriatic Sea. At both sites, Mn SOD, GSH-Px, GR and GST activities decreased in the liver in spring. In the white muscle, activities of Mn SOD, GSH-Px, GR and GST in NB decreased in spring. GR decreased in spring in EB, while CAT activity was higher in spring at both sites. The results of Principal Component Analysis (PCA) based on correlations indicated a clear separation of various sampling periods for both investigated tissues and a marked difference between two seasons. Our study is the first report on antioxidant defense enzyme activities in the red mullet in the Southern Adriatic Sea. It indicates that seasonal variations of antioxidant defense enzyme activities should be used in further biomonitoring studies in fish species.

  8. Influence of copper status on antioxidant defense and lipid peroxidation following chronic ethanol feeding in the rat

    SciTech Connect

    Greco, D.J.; Zidenberg-Cherr, S.; Han, B.; Rosenbaum, J.; Keen, C.L. )

    1991-03-11

    The effects of chronic ethanol (Et) consumption on liver antioxidant defense and lipid peroxidation were assessed in Cu sufficient (+Cu) and deficient ({minus}Cu) rats fed liquid diets with Et or dextrose (C) at 36% of kcals for 2 mo. Rats in the Et groups consumed less calories than those in the non-Et groups, thus a restricted intake group (RI) was included to account for any effects due to caloric restriction. Et feeding resulted in lower Cu and Zn and higher Mn concentrations in +Cu and {minus}Cu rats relative to C rats. Both Cu intake and Et resulted in lower CuZn superoxide dismutase (CuSOD) and glutathione peroxidase activities relative to C rats. CuZnSOD and GPx activities were lowest in {minus}CuEt rats; values were 50% of C values. In contrast, Et feeding resulted in higher MnSOD activity in +Cu and {minus}Cu rats. Despite a limited antioxidant defense system in the {minus}Cu rats, Et had no effect on mitochondrial lipid peroxidation as assessed by thiobarbituric acid reacting substances (TBARS). In contrast, microsomal TBRS production was lower in the Et fed groups; the lowest values occurring in the {minus}CuEt rats. These results suggest that in the Cu deficient animal, despite reductions in some components of the antioxidant defense system, compensatory mechanisms can arise which result in a reduction in peroxidation targets and/or an increase in alternate free radical quenching factors.

  9. [Activity of lipid peroxidation processes and the condition of antioxidative defense system in children with rheumatic fever].

    PubMed

    Shanidze, E; Zhvania, M

    2005-10-01

    Aim of study consists of establishing of some clinical-biological correlates for rheumatic fever (RF) in children, namely correlations between clinical status and lipoperoxidation products -- malonidialdehide (MDA) and antioxidative enzymes in the blood. In the neutralization process of superoxside anions ceruloplazmin (CP), catalase (CAT) and transferin (TF) are key antioxidant enzymes (AOE) of antioxidative defense system (AOD). We studied 38 patients 3-15 years of age with different variants of RF. We measured the levels of MDA, CAT, CP, TF in the plasma in patients with acute rheumatic fever (ARF) and chronic rheumatic heart disease (CRHD). In all of our cases AOE (CAT, CP, TF) were high at time of diagnosis, concomitant with increased MDA and inflammatory tests. Our study revealed intensified activity of AOD enzymes in children with RF.

  10. The Polycomb group gene Bmi1 regulates antioxidant defenses in neurons by repressing p53 pro-oxidant activity

    PubMed Central

    Chatoo, Wassim; Abdouh, Mohamed; David, Jocelyn; Champagne, Marie-Pier; Ferreira, José; Rodier, Francis; Bernier, Gilbert

    2009-01-01

    Aging may be determined by a genetic program and/or by the accumulation rate of molecular damages. Reactive oxygen species (ROS) generated by the mitochondrial metabolism have been postulated to be the central source of molecular damages and imbalance between levels of intracellular ROS and antioxidant defenses is a characteristic of the aging brain. How aging modifies free radicals concentrations and increases the risk to develop most neurodegenerative diseases is poorly understood, however. Here we show that the Polycomb group and oncogene Bmi1 is required in neurons to suppress apoptosis and the induction of a premature aging-like program characterized by reduced antioxidant defenses. Before weaning, Bmi1−/− mice display a progeroid-like ocular and brain phenotype while Bmi1+/− mice, although apparently normal, have reduced lifespan. Bmi1 deficiency in neurons results in increased p19Arf/p53 levels, abnormally high ROS concentrations and hypersensitivity to neurotoxic agents. Most Bmi1 functions on neurons oxidative metabolism are genetically linked to repression of p53 pro-oxidant activity, which also operates in physiological conditions. In Bmi1−/− neurons, p53 and co-repressors accumulate at antioxidant gene promoters, correlating with a repressed chromatin state and antioxidant genes downregulation. These findings provide a molecular mechanism explaining how Bmi1 regulates free radical concentrations and reveal the biological impact of Bmi1 deficiency on neuronal survival and aging. PMID:19144853

  11. Tocotrienol-Rich Fraction Ameliorates Antioxidant Defense Mechanisms and Improves Replicative Senescence-Associated Oxidative Stress in Human Myoblasts

    PubMed Central

    Wan Ngah, Wan Zurinah; Abdul Karim, Norwahidah

    2017-01-01

    During aging, oxidative stress affects the normal function of satellite cells, with consequent regeneration defects that lead to sarcopenia. This study aimed to evaluate tocotrienol-rich fraction (TRF) modulation in reestablishing the oxidative status of myoblasts during replicative senescence and to compare the effects of TRF with other antioxidants (α-tocopherol (ATF) and N-acetyl-cysteine (NAC)). Primary human myoblasts were cultured to young, presenescent, and senescent phases. The cells were treated with antioxidants for 24 h, followed by the assessment of free radical generation, lipid peroxidation, antioxidant enzyme mRNA expression and activities, and the ratio of reduced to oxidized glutathione. Our data showed that replicative senescence increased reactive oxygen species (ROS) generation and lipid peroxidation in myoblasts. Treatment with TRF significantly diminished ROS production and decreased lipid peroxidation in senescent myoblasts. Moreover, the gene expression of superoxide dismutase (SOD2), catalase (CAT), and glutathione peroxidase (GPX1) was modulated by TRF treatment, with increased activity of superoxide dismutase and catalase and reduced glutathione peroxidase in senescent myoblasts. In comparison to ATF and NAC, TRF was more efficient in heightening the antioxidant capacity and reducing free radical insults. These results suggested that TRF is able to ameliorate antioxidant defense mechanisms and improves replicative senescence-associated oxidative stress in myoblasts. PMID:28243354

  12. BQ123 Stimulates Skeletal Muscle Antioxidant Defense via Nrf2 Activation in LPS-Treated Rats

    PubMed Central

    Jeleń, Agnieszka; Żebrowska, Marta; Balcerczak, Ewa; Gorąca, Anna

    2016-01-01

    Little is understood of skeletal muscle tissue in terms of oxidative stress and inflammation. Endothelin-1 is an endogenous, vasoconstrictive peptide which can induce overproduction of reactive oxygen species and proinflammatory cytokines. The aim of this study was to evaluate whether BQ123, an endothelin-A receptor antagonist, influences the level of TNF-α, IL-6, SOD-1, HO-1, Nrf2 mRNA, and NF-κB subunit RelA/p65 mRNA in the femoral muscle obtained from endotoxemic rats. Male Wistar rats were divided into 4 groups (n = 6) and received iv (1) saline (control), (2) LPS (15 mg/kg), (3) BQ123 (1 mg/kg), (4) BQ123 (1 mg/kg), and LPS (15 mg/kg, resp.) 30 min later. Injection of LPS led to significant increase in levels of RelA/p65 mRNA, TNF-α, and IL-6, while content of SOD-1, HO-1, and Nrf2 mRNA was unchanged. Administration of BQ123 prior to LPS challenge resulted in a significant reduction in RelA/p65 mRNA, TNF-α, and IL-6 levels, as well as markedly elevated concentrations of SOD-1, HO-1, and Nrf2 mRNA. BQ123 appears to enhance antioxidant defense and prevent production of TNF-α and IL-6 in skeletal muscle of LPS-treated rat. In conclusion, endothelin-A receptor antagonism exerts significant impact on the skeletal muscle favouring anti-inflammatory effects and protection against oxidative stress. PMID:26823945

  13. Role of Operon aaoSo-mutT in Antioxidant Defense in Streptococcus oligofermentans

    PubMed Central

    Zhou, Peng; Liu, Lei; Tong, Huichun; Dong, Xiuzhu

    2012-01-01

    Previously, we have found that an insertional inactivation of aaoSo, a gene encoding L-amino acid oxidase (LAAO), causes marked repression of the growth of Streptococcus oligofermentans. Here, we found that aaoSo and mutT, a homolog of pyrophosphohydrolase gene of Escherichia coli, constituted an operon. Deletion of either gene did not impair the growth of S. oligofermentans, but double deletion of both aaoSo and mutT was lethal. Quantitative PCR showed that the transcript abundance of mutT was reduced for 13-fold in the aaoSo insertional mutant, indicating that gene polarity derived from the inactivation of aaoSo attenuated the expression of mutT. Enzymatic assays were conducted to determine the biochemical functions of LAAO and MutT of S. oligofermentans. The results indicated that LAAO functioned as an aminoacetone oxidase [47.75 nmol H2O2 (min·mg protein)–1]; and MutT showed the pyrophosphohydrolase activity, which removed mutagens such as 8-oxo-dGTP. Like paraquat, aaoSo mutations increased the expression of SOD, and addition of aminoacetone (final concentration, 5 mM) decreased the mutant’s growth by 11%, indicating that the aaoSo mutants are under ROS stress. HPLC did reveal elevated levels of cytoplasmic aminoacetone in both the deletion and insertional gene mutants of aaoSo. Electron spin resonance spectroscopy showed increased hydroxyl radicals in both types of aaoSo mutant. This demonstrated that inactivation of aaoSo caused the elevation of the prooxidant aminoacetone, resulting the cellular ROS stress. Our study indicates that the presence of both LAAO and MutT can prevent endogenous metabolites-generated ROS and mutagens. In this way, we were able to determine the role of the aaoSo-mutT operon in antioxidant defense in S. oligofermentans. PMID:22666463

  14. Oxidative Stress Is Associated with an Increased Antioxidant Defense in Elderly Subjects: A Multilevel Approach

    PubMed Central

    Flores-Mateo, Gemma; Elosua, Roberto; Rodriguez-Blanco, Teresa; Basora-Gallisà, Josep; Bulló, Mònica; Salas-Salvadó, Jordi; Martínez-González, Miguel Ángel; Estruch, Ramon; Corella, Dolores; Fitó, Montserrat; Fiol, Miquel; Arós, Fernando; Gómez-Gracia, Enrique; Subirana, Isaac; Lapetra, José; Ruiz-Gutiérrez, Valentina; Sáez, Guillermo T.; Covas, Maria-Isabel

    2014-01-01

    Background Studies of associations between plasma GSH-Px activity and cardiovascular risk factors have been done in humans, and contradictory results have been reported. The aim of our study was to assess the association between the scavenger antioxidant enzyme glutathione peroxidase (GSH-Px) activity in plasma and the presence of novel and classical cardiovascular risk factors in elderly patients. Methods We performed a cross-sectional study with baseline data from a subsample of the PREDIMED (PREvención con DIeta MEDiterránea) study in Spain. Participants were 1,060 asymptomatic subjects at high risk for cardiovascular disease (CVD), aged 55 to 80, selected from 8 primary health care centers (PHCCs). We assessed classical CVD risk factors, plasma oxidized low-density lipoproteins (ox-LDL), and glutathione peroxidase (GSH-Px) using multilevel statistical procedures. Results Mean GSH-Px value was 612 U/L (SE: 12 U/L), with variation between PHCCs ranging from 549 to 674 U/L (Variance = 1013.5; P<0.001). Between-participants variability within a PHCC accounted for 89% of the total variation. Both glucose and oxidized LDL were positively associated with GSH-Px activity after adjustment for possible confounder variables (P = 0.03 and P = 0.01, respectively). Conclusion In a population at high cardiovascular risk, a positive linear association was observed between plasma GSH-Px activity and both glucose and ox-LDL levels. The high GSH-Px activity observed when an oxidative stress situation occurred, such as hyperglycemia and lipid oxidative damage, could be interpreted as a healthy defensive response against oxidative injury in our cardiovascular risk population. PMID:25269026

  15. Upregulating Nrf2-dependent antioxidant defenses in Pacific oysters Crassostrea gigas: Investigating the Nrf2/Keap1 pathway in bivalves.

    PubMed

    Danielli, Naissa Maria; Trevisan, Rafael; Mello, Danielle Ferraz; Fischer, Kelvis; Deconto, Vanessa Schadeck; da Silva Acosta, Daiane; Bianchini, Adalto; Bainy, Afonso Celso Dias; Dafre, Alcir Luiz

    2017-05-01

    Analysis of the Pacific oyster Crassostrea gigas annotated genome revealed genes with conserved sequences belonging to typical cap 'n' collar Nrf2 domain, a major player in antioxidant protection, and domains belonging to Nrf2 cytoplasmic repressor (Keap1), but little is known about Nrf2/Keap1 induction in bivalves. C. gigas were exposed to waterborne 10 and 30μM curcumin, a known inducer of the mammalian Nrf2. Curcumin disappeared from the seawater after 10h, and accumulated in the gills (10h) and digestive gland (10-96h). A clear induction of glutathione (GSH)-related antioxidant defenses was observed at 96h in the gills of curcumin exposed animals (10 and 30μM), including GSH levels, and the activity of glutathione reductase (GR), glutathione peroxidase (GPx), and glutathione S-transferase (GST). This response was completely absent in the digestive gland, in line with the idea that bivalve gills act as a major site for antioxidant protection under acute exposure. The relative mRNA levels coding glutamate-cysteine ligase, GR, GPx2 and GSTpi were clearly induced by curcumin treatment (30μM, 24h). Curcumin pre-treatment for 96h increased oyster resistance to cumene hydroperoxide, but neither Nrf2 nor Keap1 genes were modulated by curcumin. However, the conserved sequences belonging to typical Nrf2 and Keap1 domains, and the notorious induction of antioxidant defense-related genes known to be controlled by Nrf2 in mammals, indicates a functional Nrf2/Keap1 pathway in bivalves, and curcumin seems to be a new tool to investigate the antioxidant response in bivalves.

  16. Heterogeneous Porphyromonas gingivalis LPS modulates immuno-inflammatory response, antioxidant defense and cytoskeletal dynamics in human gingival fibroblasts

    PubMed Central

    Herath, Thanuja D. K.; Darveau, Richard P.; Seneviratne, Chaminda J.; Wang, Cun-Yu; Wang, Yu; Jin, Lijian

    2016-01-01

    Periodontal (gum) disease is a highly prevalent infection and inflammation accounting for the majority of tooth loss in adult population worldwide. Porphyromonas gingivalis is a keystone periodontal pathogen and its lipopolysaccharide (PgLPS) acts as a major virulence attribute to the disease. Herein, we deciphered the overall host response of human gingival fibroblasts (HGFs) to two featured isoforms of tetra-acylated PgLPS1435/1449 and penta-acylated PgLPS1690 with reference to E. coli LPS through quantitative proteomics. This study unraveled differentially expressed novel biomarkers of immuno-inflammatory response, antioxidant defense and cytoskeletal dynamics in HGFs. PgLPS1690 greatly upregulated inflammatory proteins (e.g. cyclophilin, inducible nitric oxide synthase, annexins, galectin, cathepsins and heat shock proteins), whereas the anti-inflammatory proteins (e.g. Annexin A2 and Annexin A6) were significantly upregulated by PgLPS1435/1449. Interestingly, the antioxidants proteins such as mitochondrial manganese-containing superoxide dismutase and peroxiredoxin 5 were only upregulated by PgLPS1690. The cytoskeletal rearrangement-related proteins like myosin were differentially regulated by these PgLPS isoforms. The present study gives new insight into the biological properties of P. gingivalis LPS lipid A moiety that could critically modulate immuno-inflammatory response, antioxidant defense and cytoskeletal dynamics in HGFs, and thereby enhances our understanding of periodontal pathogenesis. PMID:27538450

  17. Antioxidant defense response induced by Trichoderma viride against Aspergillus niger Van Tieghem causing collar rot in groundnut (Arachis hypogaea L.).

    PubMed

    Gajera, H P; Katakpara, Zinkal A; Patel, S V; Golakiya, B A

    2016-02-01

    The study was conducted to examine the antioxidant enzymes induced by Trichoderma viride JAU60 as initial defense response during invasion of rot pathogen Aspergillus niger Van Tieghem in five groundnut varieties under pot culture. Seed treatment of T. viride JAU60 reduced 51-58% collar rot disease incidence in different groundnut varieties under pathogen infected soil culture. The activities of the antioxidant enzymes, viz., superoxide dismutase (SOD, EC 1.15.1.1), guaiacol peroxidase (GPX, EC 1.11.1.7) and ascorbate peroxidase (APX, EC 1.11.1.11), elevated in response to pathogen infection, in higher rate by tolerant varieties (J-11 and GG-2) compared with susceptible (GAUG-10, GG-13, GG-20) and further induced by T. viride treatment. Trichoderma treatment remarkably increased the 2.3 fold SOD, 5 fold GPX and 2.5 fold APX activities during disease development in tolerant varieties and the same was found about 1.2, 1.5 and 2.0 folds, respectively, in susceptible varieties. Overall, T. viride JAU60 treated seedlings (T3) witnessed higher activities of SOD (1.5 fold), GPX (3.25 fold) and APX (1.25 fold) than pathogen treatment (T2) possibly suggest the induction of antioxidant defense response by Trichoderma bio-controller to combat oxidative burst produced by invading pathogen.

  18. Effect of in vivo heart irradiation on the development of antioxidant defenses and cardiac functions in the rat

    SciTech Connect

    Benderitter, M.; Assem, M.; Maupoil, V.

    1995-10-01

    During radiotherapy of thoracic tumors, the heart is often included in the primary treatment volume, and chronic impairment of myocardial function occurs. The cellular biomolecules are altered directly by radiation or damaged indirectly by free radical production. The purpose of this investigation was to evaluate the biochemical and functional response of the rat heart to a single high dose of radiation. The effect of 20 Gy local X irradiation was determined in the heart of Wistar rats under general anesthesia. Mechanical performances were measured in vitro using an isolated perfused working heart model, and cardiac antioxidant defenses were also evaluated. Hearts were studied at 1 and 4 months after irradiation. This single dose of radiation induced a marked drop in the mechanical activity of the rat heart: aortic output was significantly reduced (18% less than control values) at 1 month postirradiation and remained depressed for the rest of the experimental period (21% less than control 4 months after treatment). This suggests the development of myocardial failure after irradiation. The decline of functional parameters was associated with changes in antioxidant defenses. The decrease in cardiac levels of vitamin E (-30%) was associated with an increase in the levels of Mn-SOD and glustathione peroxidase (+45.5% and +32%, respectively, at 4 months postirradiation). However, cardiac vitamin C and catalase levels remained constant. Since these antioxidant defenses were activated relatively long after irradiation, it is suggested that this was probable due to the production of free radical species associated with the development of inflammation. 49 refs., 8 figs., 1 tab.

  19. High dietary salt decreases antioxidant defenses in the liver of fructose-fed insulin-resistant rats.

    PubMed

    Dornas, Waleska Claudia; de Lima, Wanderson Geraldo; dos Santos, Rinaldo Cardoso; Guerra, Joyce Ferreira da Costa; de Souza, Melina Oliveira; Silva, Maísa; Souza e Silva, Lorena; Diniz, Mirla Fiuza; Silva, Marcelo Eustáquio

    2013-12-01

    In this study we investigated the hypothesis that a high-salt diet to hyperinsulinemic rats might impair antioxidant defense owing to its involvement in the activation of sodium reabsorption to lead to higher oxidative stress. Rats were fed a standard (CON), a high-salt (HS), or a high-fructose (HF) diet for 10 weeks after which, 50% of the animals belonging to the HF group were switched to a regimen of high-fructose and high-salt diet (HFS) for 10 more weeks, while the other groups were fed with their respective diets. Animals were then euthanized and their blood and liver were examined. Fasting plasma glucose was found to be significantly higher (approximately 50%) in fructose-fed rats than in the control and HS rats, whereas fat liver also differed in these animals, producing steatosis. Feeding fructose-fed rats with the high-salt diet triggered hyperinsulinemia and lowered insulin sensitivity, which led to increased levels of serum sodium compared to the HS group. This resulted in membrane perturbation, which in the presence of steatosis potentially enhanced hepatic lipid peroxidation, thereby decreasing the level of antioxidant defenses, as shown by GSH/GSSG ratio (HFS rats, 7.098±2.1 versus CON rats, 13.2±6.1) and superoxide dismutase (HFS rats, 2.1±0.05 versus CON rats, 2.3±0.1%), and catalase (HFS rats, 526.6±88.6 versus CON rats, 745.8±228.7 U/mg ptn) activities. Our results indicate that consumption of a salt-rich diet by insulin-resistant rats may lead to regulation of sodium reabsorption, worsening hepatic lipid peroxidation associated with impaired antioxidant defenses.

  20. Involvement of an antioxidant defense system in the adaptive response to cadmium in maize seedlings (Zea mays L.).

    PubMed

    Xu, Xianghua; Liu, Cuiying; Zhao, Xiaoyan; Li, Renying; Deng, Wenjing

    2014-11-01

    Chemical and biological analyses were used to investigate the growth response and antioxidant defense mechanism of maize seedlings (Zea mays L.) grown in soils with 0-100 mg kg(-1) Cd. Results showed that maize seedlings have strong abilities to accumulate and tolerate high concentrations of Cd. For soil with 50 mg kg(-1) Cd, the Cd contents in roots and shoots of maize seedlings are as large as 295.6 and 153.0 mg kg(-1) DW, respectively, without visible symptoms of toxicity. Lower soil Cd concentrations lead to a decrease in reduced glutathione (GSH) content in leaves of maize seedlings, whereas higher soil Cd concentrations resulted in an increase in the activities of superoxide dismutase, guaiacol peroxidase, catalase, and ascorbate peroxidase. Maize seedlings have strong capacities to adapt to low concentrations of Cd by consuming GSH and to develop an antioxidative enzyme system to defend against high-Cd stress.

  1. Reactive oxygen species and antioxidant defense mechanisms in the oral cavity: a literature review.

    PubMed

    San Miguel, Symone M; Opperman, Lynne A; Allen, Edward P; Svoboda, Kathy K H

    2011-01-01

    Through dental procedures and environment, periodontal tissues are exposed to many types of reactive oxygen species (ROS). Recently, various forms of antioxidants have been introduced as an approach to fight dental diseases and improve general gingival health. This article focuses on the classification of antioxidants and the link between oxidative stress and periodontal disease. The protective mechanisms of antioxidants and how routine dental procedures may increase ROS is discussed. The final section reviews the effect of tobacco products on gingival health and disease.

  2. Beta-carotene reduces oxidative stress, improves glutathione metabolism and modifies antioxidant defense systems in lead-exposed workers.

    PubMed

    Kasperczyk, Sławomir; Dobrakowski, Michał; Kasperczyk, Janusz; Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa

    2014-10-01

    The aim of this study was to determine whether beta-carotene administration reduces oxidative stress and influences antioxidant, mainly glutathione-related, defense systems in workers chronically exposed to lead. The population consisted of two randomly divided groups of healthy male volunteers exposed to lead. Workers in the first group (reference group) were not administered any antioxidants, while workers in the second group (CAR group) were treated orally with 10mg of beta-carotene once a day for 12weeks. Biochemical analysis included measuring markers of lead-exposure and oxidative stress in addition to the levels and activities of selected antioxidants. After treatment, levels of malondialdehyde, lipid hydroperoxides and lipofuscin significantly decreased compared with the reference group. However, the level of glutathione significantly increased compared with the baseline. Treatment with beta-carotene also resulted in significantly decreased glutathione peroxidase activity compared with the reference group, while the activities of other glutathione-related enzymes and of superoxide dismutase were not significantly changed. However, the activities of glucose-6-phosphate dehydrogenase and catalase, as well as the level of alpha-tocopherol, were significantly higher after treatment compared with the baseline. Despite controversy over the antioxidant properties of beta-carotene in vivo, our findings showed reduced oxidative stress after beta-carotene supplementation in chronic lead poisoning.

  3. Iron-Ascorbate-Mediated Lipid Peroxidation Causes Epigenetic Changes in the Antioxidant Defense in Intestinal Epithelial Cells: Impact on Inflammation

    PubMed Central

    Yara, Sabrina; Lavoie, Jean-Claude; Beaulieu, Jean-François; Delvin, Edgard; Amre, Devendra; Marcil, Valerie; Seidman, Ernest; Levy, Emile

    2013-01-01

    Introduction The gastrointestinal tract is frequently exposed to noxious stimuli that may cause oxidative stress, inflammation and injury. Intraluminal pro-oxidants from ingested nutrients especially iron salts and ascorbic acid frequently consumed together, can lead to catalytic formation of oxygen-derived free radicals that ultimately overwhelm the cellular antioxidant defense and lead to cell damage. Hypothesis Since the mechanisms remain sketchy, efforts have been exerted to evaluate the role of epigenetics in modulating components of endogenous enzymatic antioxidants in the intestine. To this end, Caco-2/15 cells were exposed to the iron-ascorbate oxygen radical-generating system. Results Fe/Asc induced a significant increase in lipid peroxidation as reflected by the elevated formation of malondialdehyde along with the alteration of antioxidant defense as evidenced by raised superoxide dismutase 2 (SOD2) and diminished glutathione peroxidase (GPx) activities and genes. Consequently, there was an up-regulation of inflammatory processes illustrated by the activation of NF-κB transcription factor, the higher production of interleukin-6 and cycloxygenase-2 as well as the decrease of IκB. Assessment of promoter’s methylation revealed decreased levels for SOD2 and increased degree for GPx2. On the other hand, pre-incubation of Caco-2/15 cells with 5-Aza-2′-deoxycytidine, a demethylating agent, or Trolox antioxidant normalized the activities of SOD2 and GPx, reduced lipid peroxidation and prevented inflammation. Conclusion Redox and inflammatory modifications in response to Fe/Asc -mediated lipid peroxidation may implicate epigenetic methylation. PMID:23717425

  4. Modulatory effects of deltamethrin on antioxidant defense mechanisms and lipid peroxidation in Carassius auratus gibelio liver and intestine.

    PubMed

    Dinu, Diana; Marinescu, Diana; Munteanu, Maria Cristina; Staicu, Andreea Cristina; Costache, Marieta; Dinischiotu, Anca

    2010-04-01

    Pyrethroids, such as deltamethrin, are toxic substances that lead to generation of reactive oxygen species, which harm living organisms. We assessed the level and patterns of imbalance evolved by a single dose of 2 microg/L deltamethrin on the lipid peroxidation (LPO) and the antioxidant defense system of Carassius auratus gibelio liver and intestine, and monitored the recovery dynamics of these parameters during a 14-day post-exposure period. LPO and antioxidative defense mechanisms displayed different responses in the investigated tissues. Sudden increase of LPO in the liver, persisting at this elevated level throughout the test period, was observed on the third day post-exposure, while in the intestine significant enhancement of this parameter was recorded from the seventh day. Reduced glutathione (GSH) showed a transient increase in the liver, and was depleted in the intestine by the second day of exposure, with signs of recovery by the end of the experimental tenure. In the liver of fish a temporary inhibition of superoxide dismutase (SOD) and catalase (CAT) activity, and activation of glutathione peroxidase (GPX), glutathione transferase (GST), and glutathione reductase (GR) enzymes was observed, with maximum thresholds recorded on the third and second days, respectively. In the intestine a relevant increase in CAT and GST activity up to the second day and almost complete recovery by the end of the experiment was recorded, while for GR a continuous enhancement was apparent.

  5. Calcium Supplementation Improves Na+/K+ Ratio, Antioxidant Defense and Glyoxalase Systems in Salt-Stressed Rice Seedlings

    PubMed Central

    Rahman, Anisur; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    2016-01-01

    The present study investigates the regulatory role of exogenous calcium (Ca) in developing salt stress tolerance in rice seedlings. Hydroponically grown 13-day-old rice (Oryza sativa L. cv. BRRI dhan47) seedlings were exposed to 200 mM NaCl alone and combined with 2 mM CaCl2 and 2 mM ethylene glycol tetraacetic acid (EGTA, a Ca scavenger) for 3 days. The salt stress caused growth inhibition, chlorosis and water shortage in the rice seedlings. The salt-induced stress disrupted ion homeostasis through Na+ influx and K+ efflux, and decreased other mineral nutrient uptake. Salt stress caused oxidative stress in seedlings through lipid peroxidation, loss of plasma membrane integrity, higher reactive oxygen species (ROS) production and methylglyoxal (MG) formation. The salt-stressed seedlings supplemented with exogenous Ca recovered from water loss, chlorosis and growth inhibition. Calcium supplementation in the salt-stressed rice seedlings improved ion homeostasis by inhibition of Na+ influx and K+ leakage. Exogenous Ca also improved ROS and MG detoxification by improving the antioxidant defense and glyoxalase systems, respectively. On the other hand, applying EGTA along with salt and Ca again negatively affected the seedlings as EGTA negated Ca activity. It confirms that, the positive responses in salt-stressed rice seedlings to exogenous Ca were for Ca mediated improvement of ion homeostasis, antioxidant defense and glyoxalase system. PMID:27242816

  6. Antioxidants

    MedlinePlus

    Antioxidants are man-made or natural substances that may prevent or delay some types of cell damage. Antioxidants are found in many foods, including fruits and ... are also available as dietary supplements. Examples of antioxidants include Beta-carotene Lutein Lycopene Selenium Vitamin A ...

  7. Inhibition of UVA-mediated melanogenesis by ascorbic acid through modulation of antioxidant defense and nitric oxide system.

    PubMed

    Panich, Uraiwan; Tangsupa-a-nan, Vanida; Onkoksoong, Tasanee; Kongtaphan, Kamolratana; Kasetsinsombat, Kanda; Akarasereenont, Pravit; Wongkajornsilp, Adisak

    2011-05-01

    Ascorbic acid (AA) has been well known as a skin whitening agent, although attempts have been made to evaluate its protective role against ultraviolet (UV)-induced skin hyperpigmentation or increased melanin production. While melanogenesis is a defense mechanism of the skin against UV irradiation, melanin overproduction may also contribute to melanoma initiation. UVA might play a role in melanogenesis through promoting oxidative stress, which occurs as the result of increased formation of oxidants and/or reactive nitrogen species (RNS) including nitric oxide (NO). Therefore, we investigated the antimelanogenic effect of AA (7.5-120 μM) in association with its inhibitory effect on UVA-induced oxidant formation, NO production through endothelial and inducible NO synthases (eNOS and iNOS) activation and impairment of antioxidant defense using G361 human melanoma cells. Our study demonstrated a comparable ability of AA with that of kojic acid, a well-known tyrosinase inhibitor in inhibiting mushroom tyrosinase. Melanin content was reduced by AA, but neither tyrosinase activity nor mRNA levels were reduced by AA at non-cytotoxic concentrations in UVA-irradiated G361 cells. AA was shown to inhibit UVA-mediated catalase (CAT) inactivation, glutathione (GSH) depletion, oxidant formation and NO production through suppression of eNOS and iNOS mRNA. We report herein that AA can protect against UVA-dependent melanogenesis possibly through the improvement of antioxidant defense capacity and inhibition of NO production through down-regulation of eNOS and iNOS mRNA.

  8. Transcriptional Profiles of Drought-Related Genes in Modulating Metabolic Processes and Antioxidant Defenses in Lolium multiflorum

    PubMed Central

    Pan, Ling; Zhang, Xinquan; Wang, Jianping; Ma, Xiao; Zhou, Meiliang; Huang, LinKai; Nie, Gang; Wang, Pengxi; Yang, Zhongfu; Li, Ji

    2016-01-01

    Drought is a major environmental stress that limits growth and development of cool-season annual grasses. Drought transcriptional profiles of resistant and susceptible lines were studied to understand the molecular mechanisms of drought tolerance in annual ryegrass (Lolium multiflorum L.). A total of 4718 genes exhibited significantly differential expression in two L. multiflorum lines. Additionally, up-regulated genes associated with drought response in the resistant lines were compared with susceptible lines. Gene ontology enrichment and pathway analyses revealed that genes partially encoding drought-responsive proteins as key regulators were significantly involved in carbon metabolism, lipid metabolism, and signal transduction. Comparable gene expression was used to identify the genes that contribute to the high drought tolerance in resistant lines of annual ryegrass. Moreover, we proposed the hypothesis that short-term drought have a beneficial effect on oxidation stress, which may be ascribed to a direct effect on the drought tolerance of annual ryegrass. Evidence suggests that some of the genes encoding antioxidants (HPTs, GGT, AP, 6-PGD, and G6PDH) function as antioxidant in lipid metabolism and signal transduction pathways, which have indispensable and promoting roles in drought resistance. This study provides the first transcriptome data on the induction of drought-related gene expression in annual ryegrass, especially via modulation of metabolic homeostasis, signal transduction, and antioxidant defenses to improve drought tolerance response to short-term drought stress. PMID:27200005

  9. Nitric oxide-activated calcium/calmodulin-dependent protein kinase regulates the abscisic acid-induced antioxidant defence in maize.

    PubMed

    Ma, Fangfang; Lu, Rui; Liu, Huiying; Shi, Ben; Zhang, Jianhua; Tan, Mingpu; Zhang, Aying; Jiang, Mingyi

    2012-08-01

    Nitric oxide (NO), hydrogen peroxide (H2O2), and calcium (Ca2+)/calmodulin (CaM) are all required for abscisic acid (ABA)-induced antioxidant defence. Ca2+/CaM-dependent protein kinase (CCaMK) is a strong candidate for the decoder of Ca2+ signals. However, whether CCaMK is involved in ABA-induced antioxidant defence is unknown. The results of the present study show that exogenous and endogenous ABA induced increases in the activity of ZmCCaMK and the expression of ZmCCaMK in leaves of maize. Subcellular localization analysis showed that ZmCCaMK is located in the nucleus, the cytoplasm, and the plasma membrane. The transient expression of ZmCCaMK and the RNA interference (RNAi) silencing of ZmCCaMK analysis in maize protoplasts revealed that ZmCCaMK is required for ABA-induced antioxidant defence. Moreover, treatment with the NO donor sodium nitroprusside (SNP) induced the activation of ZmCCaMK and the expression of ZmCCaMK. Pre-treatments with an NO scavenger and inhibitor blocked the ABA-induced increases in the activity and the transcript level of ZmCCaMK. Conversely, RNAi silencing of ZmCCaMK in maize protoplasts did not affect the ABA-induced NO production, which was further confirmed using a mutant of OsCCaMK, the homologous gene of ZmCCaMK in rice. Moreover, H2O2 was also required for the ABA activation of ZmCCaMK, and pre-treatments with an NO scavenger and inhibitor inhibited the H2O2-induced increase in the activity of ZmCCaMK. Taken together, the data clearly suggest that ZmCCaMK is required for ABA-induced antioxidant defence, and H2O2-dependent NO production plays an important role in the ABA-induced activation of ZmCCaMK.

  10. Nitric oxide-activated calcium/calmodulin-dependent protein kinase regulates the abscisic acid-induced antioxidant defence in maize

    PubMed Central

    Zhang, Aying; Jiang, Mingyi

    2012-01-01

    Nitric oxide (NO), hydrogen peroxide (H2O2), and calcium (Ca2+)/calmodulin (CaM) are all required for abscisic acid (ABA)-induced antioxidant defence. Ca2+/CaM-dependent protein kinase (CCaMK) is a strong candidate for the decoder of Ca2+ signals. However, whether CCaMK is involved in ABA-induced antioxidant defence is unknown. The results of the present study show that exogenous and endogenous ABA induced increases in the activity of ZmCCaMK and the expression of ZmCCaMK in leaves of maize. Subcellular localization analysis showed that ZmCCaMK is located in the nucleus, the cytoplasm, and the plasma membrane. The transient expression of ZmCCaMK and the RNA interference (RNAi) silencing of ZmCCaMK analysis in maize protoplasts revealed that ZmCCaMK is required for ABA-induced antioxidant defence. Moreover, treatment with the NO donor sodium nitroprusside (SNP) induced the activation of ZmCCaMK and the expression of ZmCCaMK. Pre-treatments with an NO scavenger and inhibitor blocked the ABA-induced increases in the activity and the transcript level of ZmCCaMK. Conversely, RNAi silencing of ZmCCaMK in maize protoplasts did not affect the ABA-induced NO production, which was further confirmed using a mutant of OsCCaMK, the homologous gene of ZmCCaMK in rice. Moreover, H2O2 was also required for the ABA activation of ZmCCaMK, and pre-treatments with an NO scavenger and inhibitor inhibited the H2O2-induced increase in the activity of ZmCCaMK. Taken together, the data clearly suggest that ZmCCaMK is required for ABA-induced antioxidant defence, and H2O2-dependent NO production plays an important role in the ABA-induced activation of ZmCCaMK. PMID:22865912

  11. Beta-carotene reduces oxidative stress, improves glutathione metabolism and modifies antioxidant defense systems in lead-exposed workers

    SciTech Connect

    Kasperczyk, Sławomir; Dobrakowski, Michał; Kasperczyk, Janusz; Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa

    2014-10-01

    The aim of this study was to determine whether beta-carotene administration reduces oxidative stress and influences antioxidant, mainly glutathione-related, defense systems in workers chronically exposed to lead. The population consisted of two randomly divided groups of healthy male volunteers exposed to lead. Workers in the first group (reference group) were not administered any antioxidants, while workers in the second group (CAR group) were treated orally with 10 mg of beta-carotene once a day for 12 weeks. Biochemical analysis included measuring markers of lead-exposure and oxidative stress in addition to the levels and activities of selected antioxidants. After treatment, levels of malondialdehyde, lipid hydroperoxides and lipofuscin significantly decreased compared with the reference group. However, the level of glutathione significantly increased compared with the baseline. Treatment with beta-carotene also resulted in significantly decreased glutathione peroxidase activity compared with the reference group, while the activities of other glutathione-related enzymes and of superoxide dismutase were not significantly changed. However, the activities of glucose-6-phosphate dehydrogenase and catalase, as well as the level of alpha-tocopherol, were significantly higher after treatment compared with the baseline. Despite controversy over the antioxidant properties of beta-carotene in vivo, our findings showed reduced oxidative stress after beta-carotene supplementation in chronic lead poisoning. - Highlights: • Beta-carotene reduces oxidative stress in lead-exposed workers. • Beta-carotene elevates glutathione level in lead-exposed workers. • Beta-carotene administration could be beneficial in lead poisoning.

  12. Enhancement of antioxidant defense system by epigallocatechin-3-gallate during bleomycin induced experimental pulmonary fibrosis.

    PubMed

    Sriram, Narayanan; Kalayarasan, Srinivasan; Sudhandiran, Ganapasam

    2008-07-01

    Oxidative stress resulting from an imbalance between radical-generating and radical scavenging systems plays an important role in the pathogenesis of pulmonary fibrosis. Epigallocatechin-3-gallate (EGCG), a polyphenol and a major component of green tea, possess a potent antioxidant property. This study was designed to evaluate the potential antioxidative activity of EGCG in the plasma and lungs during bleomycin induced experimental pulmonary fibrosis. Intratracheal administration of bleomycin (6.5 U/kg body weight) to rats resulted in significant reduction of body weight, enzymic antioxidants (superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase) and non-enzymic antioxidants (reduced glutathione, vitamin C, vitamin E and vitamin A). Elevations in lung W/D (wet weight/dry weight) ratio, hydroxyproline content was observed with a synchronized increase in lipid peroxidation markers (thiobarbituric acid reactive substances and hydroperoxides). Intraperitoneal administration of EGCG at a dose of 20 mg/kg body weight significantly improved the body weight, enzymic and non enzymic antioxidants and considerably decreased the W/D ratio, hydroxyproline and lipid peroxidation marker levels. Histological observations also correlated with the biochemical parameters. Thus, this study confirms the beneficial use of EGCG in alleviating the oxidative stress induced during pulmonary fibrosis.

  13. Role of Nrf2 antioxidant defense in mitigating cadmium-induced oxidative stress in the olfactory system of zebrafish

    SciTech Connect

    Wang, Lu; Gallagher, Evan P.

    2013-01-15

    Exposure to trace metals can disrupt olfactory function in fish leading to a loss of behaviors critical to survival. Cadmium (Cd) is an olfactory toxicant that elicits cellular oxidative stress as a mechanism of toxicity while also inducing protective cellular antioxidant genes via activation of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway. However, the molecular mechanisms of Cd-induced olfactory injury have not been characterized. In the present study, we investigated the role of the Nrf2-mediated antioxidant defense pathway in protecting against Cd-induced olfactory injury in zebrafish. A dose-dependent induction of Nrf2-regulated antioxidant genes associated with cellular responses to oxidative stress was observed in the olfactory system of adult zebrafish following 24 h Cd exposure. Zebrafish larvae exposed to Cd for 3 h showed increased glutathione S-transferase pi (gst pi), glutamate–cysteine ligase catalytic subunit (gclc), heme oxygenase 1 (hmox1) and peroxiredoxin 1 (prdx1) mRNA levels indicative of Nrf2 activation, and which were blocked by morpholino-mediated Nrf2 knockdown. The inhibition of antioxidant gene induction in Cd-exposed Nrf2 morphants was associated with disruption of olfactory driven behaviors, increased cell death and loss of olfactory sensory neurons (OSNs). Nrf2 morphants also exhibited a downregulation of OSN-specific genes after Cd exposure. Pre-incubation of embryos with sulforaphane (SFN) partially protected against Cd-induced olfactory tissue damage. Collectively, our results indicate that oxidative stress is an important mechanism of Cd-mediated injury in the zebrafish olfactory system. Moreover, the Nrf2 pathway plays a protective role against cellular oxidative damage and is important in maintaining zebrafish olfactory function. -- Highlights: ► Oxidative stress is an important mechanism of Cd-mediated olfactory injury. ► Cd induces antioxidant gene expression in the zebrafish olfactory system. ► The

  14. Effects of Dietary Lycopene Supplementation on Plasma Lipid Profile, Lipid Peroxidation and Antioxidant Defense System in Feedlot Bamei Lamb

    PubMed Central

    Jiang, Hongqin; Wang, Zhenzhen; Ma, Yong; Qu, Yanghua; Lu, Xiaonan; Luo, Hailing

    2015-01-01

    Lycopene, a red non-provitamin A carotenoid, mainly presenting in tomato and tomato byproducts, has the highest antioxidant activity among carotenoids because of its high number of conjugated double bonds. The objective of this study was to investigate the effect of lycopene supplementation in the diet on plasma lipid profile, lipid peroxidation and antioxidant defense system in feedlot lamb. Twenty-eight Bamei male lambs (90 days old) were divided into four groups and fed a basal diet (LP0, 40:60 roughage: concentrate) or the basal diet supplemented with 50, 100, and 200 mg/kg lycopene. After 120 days of feeding, all lambs were slaughtered and sampled. Dietary lycopene supplementation significantly reduced the levels of plasma total cholesterol (p<0.05, linearly), total triglycerides (TG, p<0.05) and low-density lipoprotein cholesterol (LDL-C, p<0.05), as well as atherogenic index (p<0.001), whereas no change was observed in high-density lipoprotein cholesterol (p>0.05). The levels of TG (p<0.001) and LDL-C (p<0.001) were decreased with the feeding time extension, and both showed a linear trend (p<0.01). Malondialdehyde level in plasma and liver decreased linearly with the increase of lycopene inclusion levels (p<0.01). Dietary lycopene intake linearly increased the plasma antioxidant vitamin E level (p<0.001), total antioxidant capacity (T-AOC, p<0.05), and activities of catalase (CAT, p<0.01), glutathione peroxidase (GSH-Px, p<0.05) and superoxide dismutase (SOD, p<0.05). The plasma T-AOC and activities of GSH-Px and SOD decreased with the extension of the feeding time. In liver, dietary lycopene inclusion showed similar antioxidant effects with respect to activities of CAT (p<0.05, linearly) and SOD (p<0.001, linearly). Therefore, it was concluded that lycopene supplementation improved the antioxidant status of the lamb and optimized the plasma lipid profile, the dosage of 200 mg lycopene/kg feed might be desirable for growing lambs to prevent environment

  15. [Influence of ionizing radiation on activity of enzymes of antioxidant defense of Paecilomyces lilaclvus (Thom) Samson].

    PubMed

    Tuhaĭ, T I

    2011-01-01

    The level of activity of antioxidant protection enzymes (superoxide dismutase, catalase and peroxidase) under exposure to ionizing radiation and without it in strain Paecilomyces lilacinus, showing radioadaptive properties, and in control one has been investigated. It has been established that the researched strains are characterized by the high level activity of superoxide dismutase (200-800 AU/mg protein), extracellular and intracellular catalase (0.02-40 mmol min(-1) mg(-1) protein) and peroxidase (0.2-4 mmol min(-1) mg(-1) protein). Ionizing radiation was the inducer of significant changes in antioxidant enzyme activity of the control strain (from the lack of influence to the change of activity by an order) and showed considerably less influence on their activity in the strain, showing radioadaptive properties (the activity changes by 40-50%). The complex response of antioxidant enzymes in investigated strains under the exposure to ionizing radiation has been revealed.

  16. Nucleotides protect rat brain astrocytes against hydrogen peroxide toxicity and induce antioxidant defense via P2Y receptors.

    PubMed

    Förster, Daniel; Reiser, Georg

    2016-03-01

    Consequences of neurodegenerative diseases or stroke also depend on astroglial survival during oxidative stress. P2Y receptors that are widely distributed in the central nervous system are suggested to be involved in cytoprotection. However, knowledge about the efficacy of protection by P2Y receptors and their involvement in antioxidant protective pathways is scarce. Here, we investigate the viability and reactive oxygen species (ROS) production after exposure of rat astrocytes to hydrogen peroxide. We determined the influence of treatment with the P2Y1 receptor-specific agonist 2-methyl-thio-ADP (2MeSADP) and the broad range P2Y receptor agonist adenosine 5'-(3-thiotriphosphate) (ATPγS). Preincubation (24-h before hydrogen peroxide application) and incubation with ATPγS and 2MeSADP protected astrocytes. The ROS production in hydrogen peroxide-treated astrocytes was reduced by pre- and co-incubation with ATPγS or 2MeSADP. Changes of levels of expression of antioxidant defense systems in astrocytes by treatment with P2Y receptor agonists were analyzed. Incubation with ATPγS and 2MeSADP increased mRNA levels of CAT encoding catalase and SOD2, encoding mitochondrial manganese dependent superoxide dismutase. ATPγS additionally increased mRNA levels of SOD3, encoding extracellular superoxide dismutase (ECSOD). Levels of total glutathione (GSH) increased in ATPγS/2MeSADP-treated astrocytes. mRNA levels of genes involved in GSH synthesis and in import of GSH precursors were analyzed after treatment with ATPγS and 2MeSADP. Both agonists significantly increased mRNA levels of a subunit of glutamate cysteine ligase, and a subunit of antiporter system xc(-). Changes in mRNA levels of antioxidant enzymes and genes of GSH metabolism depend on rise of intracellular Ca(2+) by P2Y receptor and basal activity of protein kinase A (PKA). SOD3 induction is suggested to depend on increased intracellular Ca(2+), increased cyclic AMP levels and PKA activity. Thus, we confirm a

  17. Positive control of a global antioxidant defense regulon activated by superoxide-generating agents in Escherichia coli.

    PubMed Central

    Greenberg, J T; Monach, P; Chou, J H; Josephy, P D; Demple, B

    1990-01-01

    Escherichia coli responds to superoxide-generating agents by inducing approximately 40 proteins. We have identified a genetic locus, soxR (superoxide response), that positively regulates 9 of these proteins during superoxide stress. Induction under soxR control is at the transcriptional level, as shown with lac fusions to five paraquat-inducible promoters. Members of the soxR regulon include at least three proteins with demonstrable antioxidant roles: Mn-containing superoxide dismutase (which destroys superoxide radicals), endonuclease IV (which repairs radical-induced damages in DNA), and glucose-6-phosphate dehydrogenase (which produces NADPH). Induction of the soxR regulon also leads to diminished levels of the major outer membrane protein OmpF and alteration of the small-subunit ribosomal protein S6. These latter changes confer resistance to a variety of antibiotics. The soxR regulon may thus operate as an inducible defense against xenobiotics in general. Images PMID:1696718

  18. [Study of free-radical processes and antioxidant defense parameters during hirudotherapy of patients with diseases of salivary glands].

    PubMed

    Abal'masov, D V; Pozharitskaia, M M; Starosel'tseva, L K; Afanas'ev, V V

    2004-01-01

    Hirudotherapy was used in the treatment of 39 patients (10 male and 29 female) aged 28-58 years with chronic sialadenitis and sialadenosis. Control group consisted of 15 normal subjects without diseases of salivary glands. Lipid peroxidation (LPO) and antioxidant defense (AOD) parameters were under study. Hirudotherapy led to improvement of the clinical status in the majority of patients with sialadenosis; the content of superoxide dismutase (SOD) normalized and ceruloplasmin (CP) level increased. The status of patients with sialadenitis also improved; catalase and glutathione peroxidase levels normalized and SOD and CP levels increased. The best therapeutic effect was attained in patients with sialadenitis. No appreciable improvement was observed in patients with chronic parenchymatous parotitis in the presence of Sjogren's syndrome.

  19. Heavy metal induced antioxidant defense system of green microalgae and its effective role in phycoremediation of tannery effluent.

    PubMed

    Ajayan, K V; Selvaraju, M

    2012-11-15

    Investigation of tannery effluent toxicology in green microalgae is of great importance from ecological point of view, because heavy metal has become a major contaminant in recent years. The present study determined the effect of various concentrations (0, 10, 25, 50, 75 and 100%) of heavy metals containing tannery effluent on cell growth and antioxidant defense system of two green microalgae. Treatment with effluent induced accumulation of reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). Lower tannery effluent concentrations increased algal growth, whereas higher concentration suppressed the growth and photosynthetic content. Both strains of the microalgae had proven effective in removing heavy metals from aqueous solutions with the highest removal efficiency being near 100% and it can be used for phycoremediation of wastewater in large scale.

  20. [The values of the lipid peroxidation-antioxidative defense system as predictors of the poor course of infiltrative pulmonary tuberculosis].

    PubMed

    Volchegorskiĭ, I A; Novoselov, P N; Bolotov, A A

    2008-01-01

    The authors have studied whether an indirect clinical-and-laboratory assessment of the extent of a destructive process in the tuberculous infiltrates and that of concomitant pleural affection can be made from the values of the lipid peroxidation-antioxidative defense (PLO-AOD) system in the blood of patients with infiltrative pulmonary tuberculosis (IPT). Regression analysis has indicated that PLO-AOD values significantly reflect the extent of X-ray verified destructions in the tuberculous infiltrates, concomitant pleural involvements, the specific features of immunity of patients with IPT. The neural network technology used to analyze the baseline PLO-AOD values has been ascertained to permit a reliable prognosis of decay cavity closure 4 months after the initiation of medical treatment and of a need for surgical treatment for IPT.

  1. [Membranous aspects of kidney transplantation and reasons of transplant antioxidant defense].

    PubMed

    Berdichevskiĭ, B A; Tsvettskikh, V E; Zhmurov, V A; Kononov, S L; Berdichevskaia, E B; Zhuravleva, T D; Kiianiuk, N S; Razumiak, T V; Nedorezoniuk, S V

    2000-01-01

    Special membranological studies of the role of antioxidant emoxipine in combined pharmacological support of stable function of the transplanted kidney in 30 patients have shown that this drug restores phospholipid pool of red cell membranes and improves their physical properties. No significant fluctuations of cyclosporin A blood concentrations were registered. Emoxipine addition to combined therapy of patients with transplanted kidney is recommended.

  2. Oral Rg1 supplementation strengthens antioxidant defense system against exercise-induced oxidative stress in rat skeletal muscles

    PubMed Central

    2012-01-01

    Background Previous studies reported divergent results on nutraceutical actions and free radical scavenging capability of ginseng extracts. Variations in ginsenoside profile of ginseng due to different soil and cultivating season may contribute to the inconsistency. To circumvent this drawback, we assessed the effect of major ginsenoside-Rg1 (Rg1) on skeletal muscle antioxidant defense system against exhaustive exercise-induced oxidative stress. Methods Forty weight-matched rats were evenly divided into control (N = 20) and Rg1 (N = 20) groups. Rg1 was orally administered at the dose of 0.1 mg/kg bodyweight per day for 10-week. After this long-term Rg1 administration, ten rats from each group performed an exhaustive swimming, and remaining rats considered as non-exercise control. Tibialis anterior (TA) muscles were surgically collected immediately after exercise along with non-exercise rats. Results Exhaustive exercise significantly (p<0.05) increased the lipid peroxidation of control group, as evidenced by elevated malondialdehyde (MDA) levels. The increased oxidative stress after exercise was also confirmed by decreased reduced glutathione to oxidized glutathione ratio (GSH/GSSG ratio) in control rats. However, these changes were completely eliminated in Rg1 group. Catalase (CAT) and glutathione peroxidase (GPx) activities were significantly (p<0.05) increased by Rg1 in non-exercise rats, while no significant change after exercise. Nevertheless, glutathione reductase (GR) and glutathione S-transferase (GST) activities were significantly increased after exercise in Rg1 group. Conclusions This study provide compelling evidences that Rg1 supplementation can strengthen antioxidant defense system in skeletal muscle and completely attenuate the membrane lipid peroxidation induced by exhaustive exercise. Our findings suggest that Rg1 can use as a nutraceutical supplement to buffer the exhaustive exercise-induced oxidative stress. PMID:22607394

  3. Nitric Oxide Mediates 5-Aminolevulinic Acid-Induced Antioxidant Defense in Leaves of Elymus nutans Griseb. Exposed to Chilling Stress.

    PubMed

    Fu, Juanjuan; Chu, Xitong; Sun, Yongfang; Miao, Yanjun; Xu, Yuefei; Hu, Tianming

    2015-01-01

    Nitric oxide (NO) and 5-aminolevulinic acid (ALA) are both extremely important signalling molecules employed by plants to control many aspects of physiology. In the present study, the role of NO in ALA-induced antioxidant defense in leaves of two sources of Elymus nutans Griseb. (Damxung, DX and Zhengdao, ZD) was investigated. Chilling stress enhanced electrolyte leakage, accumulation of malondialdehyde (MDA), hydrogen peroxide (H2O2) and superoxide radical in two E. nutans, which were substantially alleviated by exogenous ALA and NO application. Pretreatment with NO scavenger PTIO or NOS inhibitor L-NNA alone and in combination with ALA induced enhancements in electrolyte leakage and the accumulation of MDA, H2O2 and superoxide radical in leaves of DX and ZD exposed to chilling stress, indicating that the inhibition of NO biosynthesis reduced the chilling resistance of E. nutans and the ALA-enhanced chilling resistance. Further analyses showed that ALA and NO enhanced antioxidant defense and activated plasma membrane (PM) H+-ATPase and decreased the accumulation of ROS induced by chilling stress. A pronounced increase in nitric oxide synthase (NOS) activity and NO release by exogenous ALA treatment was found in chilling-resistant DX plants exposed to chilling stress, while only a little increase was observed in chilling-sensitive ZD. Furthermore, inhibition of NO accumulation by PTIO or L-NNA blocked the protective effect of exogenous ALA, while both exogenous NO treatment and inhibition of endogenous NO accumulation did not induce ALA production. These results suggested that NO might be a downstream signal mediating ALA-induced chilling resistance in E. nutans.

  4. Antioxidant defenses and biochemical changes in pacu (Piaractus mesopotamicus) in response to single and combined copper and hypoxia exposure.

    PubMed

    Garcia Sampaio, Fernanda; de Lima Boijink, Cheila; Tie Oba, Eliane; Romagueira Bichara dos Santos, Laila; Lúcia Kalinin, Ana; Tadeu Rantin, Francisco

    2008-01-01

    The effect of combined-factors (hypoxia+copper) on the biochemical parameters and antioxidant defenses were studied in the neotropical fish Piaractus mesopotamicus. Fish were exposed for 48 h to 0.4 mg Cu(2+) L(-1) (0.4Cu), hypoxia=50 mm Hg (Hpx), and 0.4 mg Cu(2) L(-1)+hypoxia=50 mm Hg (0.4CuHpx). The exposure to 0.4Cu increased the reactive oxygen species (ROS) in the liver, accompanied by increases in superoxide dismutase (SOD) and decreases in catalase (CAT) activity, showing the influence of copper in this protection. The exposure to Hpx decreased the activity of glutathione peroxidase (GSH-Px) and CAT. Exposure to a combined-factor caused an increase in the ROS production followed by an increase in SOD and a decrease in GSH-Px and CAT. At 0.4Cu, fish presented a reduction in CAT, while in Hpx decreases in SOD, CAT and GSH-Px were observed in red muscles. Single-factors were insufficient to cause ROS production. In combined-factors, increased ROS formation and decreased SOD, CAT and GSH-Px were observed. RBC increased in all groups, but only under combined-factors was there an increase in hemoglobin. Copper plasma concentration increased in groups exposed to copper. Na(+)/K(+)-ATPase activity in gills decreased in 0.4Cu and 0.4CuHpx, and increased in Hpx. Metallothionein concentration in gills increased under combined-factors. Combined-factors caused significant disturbances in the antioxidant defenses and biochemical parameters than single-factors.

  5. Modulation of lipid peroxidation and antioxidant defense systems in rat intestine by subchronic fluoride and ethanol administration.

    PubMed

    Chauhan, Shailender Singh; Ojha, Sudarshan; Mahmood, Akhtar

    2011-11-01

    Excessive consumption of fluoride and ethanol has been identified as injurious to human health. Fluoride and ethanol co-exposures are commonly seen among the alcoholics residing in endemic fluoride areas worldwide. This study was undertaken to examine the modulation of lipid peroxidation and antioxidant defense systems in rat intestine by subchronic fluoride and ethanol administration. Female Sprague-Dawley rats were divided into four groups: group I (control), group II (fluoride was given orally at a dose of 25 mg/kg body weight), group III (30% ethanol was given orally at a dose of 1 mL/kg body weight), and group IV (a combination of fluoride and ethanol was administered orally at the dose described for groups II and III). Lipid peroxidation was elevated (P<.05) in intestine of rats by fluoride or ethanol treatments for 20 or 40 days. However, glutathione content was reduced by fluoride (32 and 44%) and ethanol (21 and 40%) treatments after 20 and 40 days, respectively. Fluoride-exposed animals showed reduction (P<.05) in the activities of superoxide dismutase (22 and 42%), catalase (30 and 37%), glutathione peroxidase (22 and 35%), glutathione reductase (32 and 34%), and glutathione-S-transferase (24 and 30%) after 20 and 40 days. A similar decrease (P<.05) in the activities of these enzymes was also noticed in animals exposed to ethanol for 20 or 40 days. The observed changes in lipid peroxidation, reduced glutathione levels, and enzyme systems were further augmented in intestine of rats exposed to fluoride and ethanol together. Intestinal histology showed large reactive lymphoid follicles along with mild excess of lymphocytes in lamina propria of villi, villous edema, focal ileitis, and necrosis of villi in animals exposed to fluoride and ethanol for 40 days. These findings suggest that fluoride and ethanol exposure induces considerable changes in lipid peroxidation, antioxidant defense, and morphology of rat intestine, which may affect its functions.

  6. The xanthophyll cycle and antioxidative defense system are enhanced in the wheat hybrid subjected to high light stress.

    PubMed

    Chen, Xiaoying; Li, Wei; Lu, Qingtao; Wen, Xiaogang; Li, Hongwei; Kuang, Tingyun; Li, Zhensheng; Lu, Congming

    2011-10-15

    Although the wheat hybrids have often shown higher grain yields, the physiological basis of the higher yields remains unknown. Previous studies suggest that tolerance to photoinhibition in the hybrid may be one of the physiological bases (Yang et al., 2006, Plant Sci 171:389-97). The objective of this study was to further investigate the possible mechanism responsible for tolerance to photoinhibition in the hybrid. Photosystem II (PSII) photochemistry, the xanthophyll cycle, and antioxidative defense system were compared between the hybrid and its parents subjected to high light stress (1500μmolm(-2)s(-1)). The analyses of oxygen-evolving activity, chlorophyll fluorescence, and protein blotting demonstrated that the higher tolerance in the hybrid than in its parents was associated with its higher tolerance of PSII to photoinhibition. High light induced an increase in non-photochemical quenching, and this increase was greater in the hybrid than in its parents. There were no differences in the pool size of the xanthophyll cycle between the hybrid and its parents. The content of violaxanthin decreased significantly, whereas the content of zeaxanthin+antherxanthin increased considerably during high light treatments. However, the decrease in violaxanthin content and the increase in zeaxanthin+antherxanthin content were greater in the hybrid than in its parents. High light resulted in a significant accumulation of H(2)O(2), O(2)(-) and catalytic Fe, and this accumulation was less in the hybrid than in its parents. High light induced a significant increase in the activities of superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase, and these increases were greater in the hybrid than its parents. These results suggest that the higher tolerance to photoinhibition in the hybrid may be associated with its higher capacity for antioxidative defense metabolism and the xanthophyll cycle.

  7. Changes in Antioxidant Defense System Using Different Lipid Emulsions in Parenteral Nutrition in Children after Hematopoietic Stem Cell Transplantation

    PubMed Central

    Baena-Gómez, María Auxiliadora; De La Torre Aguilar, María José; Mesa, María Dolores; Pérez Navero, Juan Luis; Gil-Campos, Mercedes

    2015-01-01

    Background: Traditionally, lipids used in parenteral nutrition (PN) are based on ω-6 fatty acid-rich vegetable oils, such as soybean oil, with potential adverse effects involving oxidative stress. Methods: We evaluated the antioxidant defense system in children, after hematopoietic stem cell transplantation (HSCT), who were randomized to use a lipid emulsion with fish oil or soybean oil. Blood samples at baseline, at 10 days, and at the end of the PN were taken to analyze plasma retinol, α-tocopherol, β-carotene, coenzyme Q9 and coenzyme Q10 levels, and catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPOX), and superoxide dismutase (SOD) levels in lysed erythrocytes. Results: An increase in plasma α-tocopherol levels in the group of patients receiving the fish oil-containing emulsion (FO) compared with the group receiving the soybean emulsion was observed at day 10 of PN. Concurrently, plasma α-tocopherol increased in the FO group and β-carotene decreased in both groups at day 10 compared with baseline levels, being more significant in the group receiving the FO emulsion. Conclusion: FO-containing emulsions in PN could improve the antioxidant profile by increasing levels of α-tocopherol in children after HSCT who are at higher risk of suffering oxidative stress and metabolic disorders. PMID:26343717

  8. Effect of delta-9-tetrahydrocannabinol on altered antioxidative enzyme defense mechanisms and lipid peroxidation in mice testes.

    PubMed

    Mandal, Tapas Kumar; Das, Niladri Sekhar

    2009-04-01

    The present study examined the adverse effects of delta-9-tetrahydrocannabinol (i.p injection in albino mice) on free radical damage of testicular lipids (lipid peroxidation) at low doses and the role of antioxidant enzymes defense system at high dose and particularly at the withdrawal of the drug after applying higher dose (recovery dose). At lower doses (total doses ranging from 6 mg to 28 mg), there was a significant increase of lipid peroxidation and decrease in testicular lipid content. But the effects were slightly lowered at high dose (total dose 70 mg) and at the withdrawal of the drug (recovery dose). Similarly, marked decrease of antioxidant enzyme systems (superoxide dismutase, catalase, and glutathione peroxidase) and glutathione content were noticed at low doses. But the effects were slightly higher at high dose and at the withdrawal of the drug. Similarly, low-dose treatments caused significant shrinkage of tubular diameter and detrimental changes in seminiferous epithelium of testis resulting in lowered plasma testosterone and pituitary gonadotropins (follicular stimulating and luteinizing hormone levels. But at high dose and particularly at withdrawal of the drug, regression of seminiferous tubules and recovery of various germ cell layers of testes through the revival of testosterone hormone and pituitary gonadotropins were observed.

  9. Purine nucleoside phosphorylase and the enzymatic antioxidant defense system in breast milk from women with different levels of arsenic exposure.

    PubMed

    Gaxiola-Robles, Ramón; Labrada-Martagón, Vanessa; Bitzer-Quintero, Oscar Kurt; Zenteno-Savín, Tania; Méndez-Rodríguez, Lía Celina

    2015-05-01

    Purine nucleoside phosphorylase (PNP) is an ubiquitous enzyme which plays an important role in arsenic (As) detoxification. As is a toxic metalloid present in air, soil and water; is abundant in the environment and is readily transferred along the trophic chain, being found even in human breast milk. Milk is the main nutrient source for the growth and development of neonates. Information on breast milk synthesis and its potential defense mechanism against As toxicity is scarce. In this study, PNP and antioxidant enzymes activities, as well as glutathione (GSH) and total arsenic (TAs) concentrations, were quantified in breast milk samples. PNP, superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) activities and GSH concentration were determined spectrophotometrically; TAs concentration ([TAs]) was measured by atomic absorption spectrometry. Data suggest an increase in PNP activity (median = 0.034 U mg protein-1) in the presence of TAs (median = 1.16 g L(-1)). To explain the possible association of PNP activity in breast milk with the activity of the antioxidant enzymes as well as with GSH and TAs concentrations, generalized linear models were built. In the adjusted model, GPx and GR activities showed a statistically significant (p<0.01) association with PNP activity. These results may suggest that PNP activity increases in the presence of TAs as part of the detoxification mechanism in breast milk.

  10. Alterations in antioxidant defense system of workers chronically exposed to arsenic, cadmium and mercury from coal flying ash.

    PubMed

    Zeneli, Lulzim; Sekovanić, Ankica; Ajvazi, Majlinda; Kurti, Leonard; Daci, Nexhat

    2016-02-01

    Humans are exposed to different stress factors that are responsible for over-production of reactive oxygen species. Exposure to heavy metals is one of these factors. The aim of the study was to analyze the effect of chronic exposure to heavy metals through coal flying ash on the efficiency of antioxidative defensive mechanisms, represented by the activity of superoxide dismutase, glutathione peroxidase and ascorbic acid. Nonessential elements such as arsenic and mercury levels showed a significant increase (p > 0.001) in the power plant workers rather than in the control subjects. There were no significant differences of blood cadmium between power plant workers and control subjects. We found a significant positive correlation (p < 0.05) between BAs/SZn (r = 0.211), BAs/BSe (r = 0.287), BCd/SCu (r = 0.32) and BHg/BSe (r = 0.263) in the plant workers. Red blood cell antioxidant enzymes and plasma ascorbic acid were significantly lower in power plants workers than in the control group (p < 0.002). We can conclude that levels of mercury, arsenic and cadmium in blood, despite their concentration within the reference values, significantly affect plasma ascorbic acid concentration, superoxide dismutase and glutathione peroxidase activity, which are able to increase the risk of oxidative stress.

  11. Effects of the herbicide isoproturon on metallothioneins, growth, and antioxidative defenses in the aquatic worm Tubifex tubifex (Oligochaeta, Tubificidae).

    PubMed

    Mosleh, Yahia Y; Paris-Palacios, Séverine; Couderchet, Michel; Biagianti-Risbourg, Sylvie; Vernet, Guy

    2005-07-01

    Metallothioneins (MTs) are low molecular weight proteins, mainly implicated in metal ion detoxification. Increase in MT contents is considered to be a specific biomarker of metal exposure. Recently it has been demonstrated that MTs participate in several cellular functions such as regulation of growth, and antioxidative defenses. Therefore, the induction of MTs as biomarkers of exposure to the pesticide isoproturon has been investigated in the aquatic worms Tubifex tubifex. MT levels in exposed worms increased significantly (p < 0.05) after 2, 4, and 7 days of exposure to different concentrations of isoproturon (maximum increase compared to unexposed controls: +148.56% for 10 mg l(-1) after 4 days of exposure). In response to isoproturon, the activity of glutathione-S-transferase (max. +52%), glutathione-reductase (max. +100%), and catalase (max. +117%) increased, demonstrating the occurrence of an oxidative stress response to the herbicide. Thus, the increase in MT contents caused by isoproturon was interpreted as a defense response towards increased oxidative stress generated by the herbicide. Residues of isoproturon and its metabolites, 1-(4-isopropylphenyl)-3-methylurea, 1-(4-isopropylphenyl) urea, and 4-isopropylanilin were detected in the worm growth medium. Half-life of the herbicide was shorter at a low (0.1 mg l(-1)) initial concentration. The herbicide accumulated in T. tubifex but no metabolite could be detected.

  12. Efficiency of photodynamic therapy on WM35 melanoma with synthetic porphyrins: Role of chemical structure, intracellular targeting and antioxidant defense.

    PubMed

    Baldea, Ioana; Olteanu, Diana Elena; Bolfa, Pompei; Ion, Rodica Mariana; Decea, Nicoleta; Cenariu, Mihai; Banciu, Manuela; Sesarman, Alina Viorica; Filip, Adriana Gabriela

    2015-10-01

    Photodynamic therapy (PDT) could be an adjuvant therapy in melanoma, an aggressive cancer that arises from melanocytes. Several reports showed encouraging results of the efficacy of PDT in melanoma on experimental models and in clinical trials. Therefore, we studied the efficacy of two derivatives of tetraphenylporphyrin (TPP): meso-5,10,15,20-tetrakis (4-hydroxyphenyl) porphyrin (THOPP) and meso-5-(4-hydroxyphenyl)-10,15,20-tris (4-methoxyphenyl) porphyrin (THOMPP) as photosensitizers for PDT, compared to FDA approved delta aminolevulinic acid (ALA) against a lightly pigmented, melanoma cell line, WM35, in vitro. Both porphyrins were more efficient as photosensitizers, compared to ALA, without dark toxicity. The efficiency depended on the intracellular localization and the molecule structure. THOPP, the most efficient porphyrin localized mainly in mitochondria, while THOMPP accumulated in lysosomes; both showed melanosomal localization. The symmetric THOPP molecule was able to generate increased oxidative stress damage and apoptosis. THOPP also induced a low effect on the defense mechanisms like antioxidant enzyme SOD (superoxide dismutase), NF-kB (nuclear transcription factor kB) activation and MITF (microphthalmia transcription factor). The lower efficiency of the asymmetric molecule, THOMPP was probably due to a diminished photoactivation, which led to a lower ROS induced damage, combined with higher activation of the defense mechanisms.

  13. NADPH oxidase-dependent H2O2 production is required for salt-induced antioxidant defense in Arabidopsis thaliana.

    PubMed

    Ben Rejeb, Kilani; Benzarti, Maâli; Debez, Ahmed; Bailly, Christophe; Savouré, Arnould; Abdelly, Chedly

    2015-02-01

    The involvement of hydrogen peroxide (H2O2) generated by nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase) in the antioxidant defense system was assessed in salt-challenged Arabidopsis thaliana seedlings. In the wild-type, short-term salt exposure led to a transient and significant increase of H2O2 concentration, followed by a marked increase in catalase (CAT, EC 1.11.16), ascorbate peroxidase (APX, EC 1.11.1.11) and glutathione reductase (GR, EC 1.6.4.2) activities. Pre-treatment with either a chemical trap for H2O2 (dimethylthiourea) or two widely used NADPH oxidase inhibitors (imidazol and diphenylene iodonium) significantly decreased the above-mentioned enzyme activities under salinity. Double mutant atrbohd/f plants failed to induce the antioxidant response under the culture conditions. Under long-term salinity, the wild-type was more salt-tolerant than the mutant based on the plant biomass production. The better performance of the wild-type was related to a significantly higher photosynthetic activity, a more efficient K(+) selective uptake, and to the plants' ability to deal with the salt-induced oxidative stress as compared to atrbohd/f. Altogether, these data suggest that the early H2O2 generation by NADPH oxidase under salt stress could be the beginning of a reaction cascade that triggers the antioxidant response in A. thaliana in order to overcome the subsequent reactive oxygen species (ROS) production, thereby mitigating the salt stress-derived injuries.

  14. Effect of melatonin in the antioxidant defense system in the locomotor muscles of the estuarine crab Neohelice granulata (Decapoda, Brachyura).

    PubMed

    Geihs, Márcio Alberto; Vargas, Marcelo Alves; Maciel, Fábio Everton; Caldas, Sergiane Souza; Cruz, Bruno Pinto; Primel, Ednei Gilberto; Monserrat, José Maria; Nery, Luiz Eduardo Maia

    2010-03-01

    In vertebrates, many studies verified different effects of melatonin in the antioxidant defense system (ADS). In crustaceans, few studies have been conducted to verify this possibility. We verified the melatonin effects in the crab Neohelice granulata using low (0.002 and 0.02 pmol/crab) and high (2.0 and 20.0 pmol/crab) melatonin dosages in short-term (0.5h) and long-term (9.5h) experiments. We analyzed the antioxidant capacity against peroxyl radicals (ACAP), reactive oxygen species (ROS) concentration, levels of by products of lipid peroxidation (LPO), oxygen consumption (VO(2)), the activity of glutamate cysteine ligase (gamma-GCL) and catalase (CAT) and glutathione content (GSH). Finally, the effects of exogenous melatonin were verified in terms of melatonin and N(1)-acetyl-N(2)-formyl-5-methoxykynuramine (AFMK) content in the muscles of N. granulata. In short-term experiment and low dosages, melatonin increased the VO(2), gamma-GCL activity and GSH content (p<0.05) and decreased melatonin content (p<0.05) without effects in ROS, ACAP and LPO (p>0.05). Possibly, melatonin is acting in the ADS increasing its efficiency and/or acting in mitochondrial activity and/or through signaling muscles to increase its consumption. AFMK was only detected in the eyestalk and cerebroid ganglia. In high dosages melatonin effects decreased, possibly by the desensitization of their receptors. In long-term experiment, melatonin decreased ACAP (p<0.05), and CAT activity (p<0.05) in low dosages. In high dosages melatonin reduced VO(2) (p<0.05) and increased ACAP (p<0.05), possibly stimulating others components of the ADS. In conclusion, melatonin in the locomotor muscles of N. granulata affects the antioxidant/pro-oxidant balance in a time and dosage dependent manner.

  15. Responses of antioxidant defenses and membrane damage to drought stress in fruit bodies of Auricularia auricula-judae.

    PubMed

    Ma, Huailiang; Xu, Xiuhong; Feng, Lijian

    2014-01-01

    Fruit bodies of Auricularia auricula-judae are often subjected to drought stress and became dormant. The responses of antioxidant defenses and membrane damage to drought stress were investigated in this study. Picked fruit bodies were exposed to sunlight and dehydrated naturally and samples were collected at different levels of water loss (0, 10, 30, 50, and 70%) for determination of electrolyte leakage (EL); contents of malondialdehyde (MDA), ascorbic acid (AsA) and reduced glutathione (GSH); and activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). Results showed that membrane permeability (assessed by EL) and membrane lipid peroxidation (MDA content) remained unchanged at all levels of water loss studied. Contents of AsA and GSH showed no change at 0, 10 and 30% of water loss, however, both of them increased significantly at 50 and 70% of water loss. SOD activity significantly increased with the rising of water loss from 0 to 30%, reached the peak at 30 and 50% of water loss, and then significantly decreased at 70% of water loss. A gradual increase in POD and CAT activities was observed when water loss rose from 0 to 50%. As water loss went up to 70%, POD activity remained the same as that at 50%, but CAT activity decreased. The results indicate that the increased activities of enzymatic antioxidants (SOD, CAT and POD) and contents of non-enzymatic antioxidants (AsA and GSH) in fruit bodies of A. auricula-judae can effectively scavenge reactive oxygen species, cause no damage to cell membranes as demonstrated by the unchanged EL and MDA content, and contribute to dormancy under drought stress.

  16. Effect of phosphogypsum on growth, physiology, and the antioxidative defense system in sunflower seedlings.

    PubMed

    Elloumi, Nada; Zouari, Mohamed; Chaari, Leila; Abdallah, Ferjani Ben; Woodward, Steve; Kallel, Monem

    2015-10-01

    Phosphogypsum (PG) is the solid waste product of phosphate fertilizer production and is characterized by high concentrations of salts, heavy metals, and certain natural radionuclides. The work reported in this paper examined the influence of PG amendment on soil physicochemical proprieties, along with its potential impact on several physiological traits of sunflower seedlings grown under controlled conditions. Sunflower seedlings were grown on agricultural soil substrates amended with PG at rates of 0, 2.5, and 5 %. The pH of the soil decreased but electrical conductivity and organic matter, calcium, phosphorus, sodium, and heavy metal contents increased in proportion to PG concentration. In contrast, no variations were observed in magnesium content and small increases were recorded in potassium content. The effects of PG on sunflower growth, leaf chlorophyll content, nutritional status, osmotic regulator content, heavy metal accumulation, and antioxidative enzymes were investigated. Concentrations of trace elements in sunflower seedlings grown in PG-amended soil were considerably lower than ranges considered phytotoxic for vascular plants. The 5 % PG dose inhibited shoot extension and accumulation of biomass and caused a decline in total protein content. However, chlorophyll, lipid peroxidation, proline and sugar contents, and activities of antioxidant enzymes such as superoxide dismutase and catalase increased. Collectively, these results strongly support the hypothesis that enzymatic antioxidation capacity is an important mechanism in tolerance of PG salinity in sunflower seedlings.

  17. Cerebral Epiphyseal Proteins and Melatonin Modulate the Hepatic and Renal Antioxidant Defense of Rats

    PubMed Central

    Bharti, Vijay K.; Srivastava, R. S.; Subramaian, P.; Warren Spence, D.; Pandi-Perumal, S. R.; Brown, Gregory M.

    2011-01-01

    The cerebral epiphysis (pineal gland) secrets melatonin and number of other proteins and peptides. It was thus hypothesized that antioxidant properties of epiphyseal proteins and melatonin could potentially benefit from exogenous therapies. In view of the therapeutic potential of these proteins, the present experiment was conducted to investigate the effect of buffalo epiphyseal proteins (BEP, at 100 μg/kg BW, i.p.) and melatonin (MEL, at 10 mg/kg BW, i.p) on changes in hepatic and renal antioxidant enzymes of adult female Wistar rats. Buffalo epiphyseal proteins significantly (P < .05) increased hepatic lipid peroxidation (LPO), superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx), reduced glutathione (GSH), and renal LPO, catalase (CAT), GR, GSH, GPx levels as compared to control animals. Similarly, MEL treatment significantly (P < .05) up-regulated hepatic SOD and GPx activity, whereas CAT, GR, GPx, and GSH levels in renal tissues were increased while SOD and LPO remained unaffected. Buffalo epiphyseal protein treatment produced greater effects on hepatic GPx and renal CAT and GSH levels than did MEL. These findings support the conclusion that buffalo epiphyseal proteins and melatonin activate a number of antioxidant mechanisms in hepatic and renal tissues. PMID:21660111

  18. Levels of antioxidant defenses are decreased in bovine spermatozoa after a cycle of freezing and thawing.

    PubMed

    Bilodeau, J F; Chatterjee, S; Sirard, M A; Gagnon, C

    2000-03-01

    Growing evidence suggests that the generation of reactive oxygen species (ROS) and their detoxification by antioxidants plays a very important role in fertility. However, the relationship between the level of antioxidants in spermatozoa and the decreased fecundity following a freeze/thaw cycle remains poorly understood. We assessed the activities of antioxidant enzymes such as catalase, glutathione peroxidase (GPx), superoxide dismutase (SOD), and levels of reduced/oxidized glutathione (GSH/GSSG) in bovine semen. Sperm cells were isolated using a Percoll gradient to avoid contamination from seminal plasma, cellular debris, and other cell types. We found that bovine spermatozoa are poorly adapted to metabolize the toxic hydrogen peroxide (H(2)O(2)). Indeed, very low levels of GPx and an absence of catalase were observed. We also studied the effect of freezing and thawing bovine spermatozoa in a egg yolk-Tris-glycerol extender (EYTG). Cryopreservation significantly reduced sperm GSH levels by 78% and SOD activity by 50%. We also investigated whether the decrease in GSH level could be linked to oxidative metabolism and found that a greater reduction in intracellular GSH level occurred when fresh sperm cells were incubated in EYTG for 6 hr at 38.5 degrees C under aerobic conditions than when incubated under restricted oxygen availability. Our results strongly suggest the involvement of an oxidative stress during a freeze/thaw cycle and are consistent with the hypothesis that ROS generated during such a cycle are detrimental to sperm function.

  19. Endomorphins, endogenous opioid peptides, provide antioxidant defense in the brain against free radical-induced damage.

    PubMed

    Lin, Xin; Yang, Ding-Jian; Cai, Wen-Qing; Zhao, Qian-Yu; Gao, Yan-Feng; Chen, Qiang; Wang, Rui

    2003-11-20

    Oxidative stress has been considered to be a major cause of cellular injuries in a variety of chronic health problems, such as carcinogenesis and neurodegenerative disorders. The brain appears to be more susceptible to oxidative damage than other organs. Therefore, the existence of antioxidants may be essential in brain protective systems. The antioxidative and free radical scavenging effects of endomorphin 1 (EM1) and endomorphin 2 (EM2), endogenous opioid peptides in the brain, have been investigated in vitro. The oxidative damage was initiated by a water-soluble initiator 2,2'-azobis(2-amidinopropane hydrocholoride) (AAPH) and hydrogen peroxide (H2O2). The linoleic acid peroxidation, DNA and protein damage were monitored by formation of hydroperoxides, by plasmid pBR 322 DNA nicking assay and single-cell alkaline electrophoresis, and by SDS-polyacrylamide gel electrophoresis. Endomorphins can inhibit lipid peroxidation, DNA strand breakage, and protein fragmentation induced by free radical. Endomorphins also reacted with galvinoxyl radicals in homogeneous solution, and the pseudo-first-order rate constants were determined spectrophotometrically by following the disappearance of galvinoxyl radicals. In all assay systems, EM1 was more potent than EM2 and GSH, a major intracellular water-soluble antioxidant. We propose that endomorphins are one of the protective systems against free radical-induced damage in the brain.

  20. Antioxidant Enzyme Responses Induced by Whiteflies in Tobacco Plants in Defense against Aphids: Catalase May Play a Dominant Role

    PubMed Central

    Zhao, Haipeng; Sun, Xia; Xue, Ming; Zhang, Xiao; Li, Qingliang

    2016-01-01

    led to the suppression of the B. tabaci mediated PR-2a expression. Conclusions/Significance Aphid resistance in plants infested with B. tabaci nymphs is associated with enhanced antioxidant activities in which CAT may play a dominant role. This resistance probably acted via interactions with SA-mediated defense responses. PMID:27788203

  1. EDTA enhanced plant growth, antioxidant defense system, and phytoextraction of copper by Brassica napus L.

    PubMed

    Habiba, Ume; Ali, Shafaqat; Farid, Mujahid; Shakoor, Muhammad Bilal; Rizwan, Muhammad; Ibrahim, Muhammad; Abbasi, Ghulam Hasan; Hayat, Tahir; Ali, Basharat

    2015-01-01

    Copper (Cu) is an essential micronutrient for normal plant growth and development, but in excess, it is also toxic to plants. The present study investigated the influence of ethylenediaminetetraacetic acid (EDTA) in enhancing Cu uptake and tolerance as well as the morphological and physiological responses of Brassica napus L. seedlings under Cu stress. Four-week-old seedlings were transferred to hydroponics containing Hoagland's nutrient solution. After 2 weeks of transplanting, three levels (0, 50, and 100 μM) of Cu were applied with or without application of 2.5 mM EDTA and plants were further grown for 8 weeks in culture media. Results showed that Cu alone significantly decreased plant growth, biomass, photosynthetic pigments, and gas exchange characteristics. Cu stress also reduced the activities of antioxidants, such as superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), and catalase (CAT) along with protein contents. Cu toxicity increased the concentration of reactive oxygen species (ROS) as indicated by the increased production of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in both leaves and roots. The application of EDTA significantly alleviated Cu-induced toxic effects in B. napus, showing remarkable improvement in all these parameters. EDTA amendment increased the activity of antioxidant enzymes by decreasing the concentrations of MDA and H2O2 both in leaves and roots of B. napus. Although, EDTA amendment with Cu significantly increased Cu uptake in roots, stems, and leaves in decreasing order of concentration but increased the growth, photosynthetic parameters, and antioxidant enzymes. These results showed that the application of EDTA can be a useful strategy for phytoextraction of Cu by B. napus from contaminated soils.

  2. Effects of grape pomace on the antioxidant defense system in diet-induced hypercholesterolemic rabbits

    PubMed Central

    Choi, Chang-Sook; Chung, Hae-Kyung; Choi, Mi-Kyung

    2010-01-01

    The effects of grape seeds extract and grape peels extract prepared from grape pomace on the activity of antioxidant enzymes, degree of lipid peroxidation in serum and liver tissue were investigated in rabbits fed on high cholesterol diet. New Zealand white rabbits were divided as follows ; 1) NOR (normal group); 2) CHOL (cholesterol group); 3) GSH (cholesterol + grape seed extract group); 4) GPE (cholesterol + grape peel extract); 5) GSP (cholesterol + grape seed powder); 6) GPP (cholesterol + grape peel powder); 7) GE (cholesterol + grape seed and peel extract); 8) GP (cholesterol + grape seed and peel powder). Eight groups of rabbits were studied for 8 weeks. At the end of the experimental period, rabbits were sacrificed and the liver tissue were removed. Then, GSH, GPx, GST, CAT and MDA in the liver were measured. In liver tissues, total glutathione contents (GSH), glutathione peroxidase (GPx) and catalase (CAT) activity, which was significantly higher by grape seed extract supplementation. The level of malondialdehyde (MDA) was lower in the serum of rabbits fed grape seed extract or grape peel powder plus cholesterol than in the serum of rabbits fed cholesterol alone. It is therefore likely that grape seed extract prepared from grape pomace functioned as antioxidants in vivo, negating the effects of the oxidative stress induced by 1% cholesterol diet. The grape seed extract was found effective in converting the oxidized glutathione into reduced glutathione, and in removing H2O2 that is created by oxidative stress. The grape peel powder was found to have small influence on reduced glutathione content, CAT and GPX activity, but it increased GST activity in liver tissues, resulting in promoting the combination of lipid peroxide and glutathione (GSH), and further, lowering the formation of lipid peroxide in the serum. Therefore, grape pomace (grape seed extract and grape peel powder) supplementation is considered to activate the antioxidant enzyme system and

  3. Antioxidant defenses of mycorrhizal fungus infection against SO(2)-induced oxidative stress in Avena nuda seedlings.

    PubMed

    Huang, L L; Yang, C; Zhao, Y; Xu, X; Xu, Q; Li, G Z; Cao, J; Herbert, S J; Hao, L

    2008-11-01

    Colonization of arbuscular mycorrhizal fungi Glomus mosseae increased Avena nuda seedling tolerance to SO(2) exposure, as indicated by elevated total plant biomass and ameliorative photosynthetic rate, when compared to the non-mycorrhizal plants. This is associated with an improved antioxidant capacity as shown by enhanced superoxide dismutase and catalase activity, increased ascorbic acid and glutathione content, and reduced malondialdehyde and hydrogen peroxide level in the mycorrhizal plants relative to the non-mycorrhizal plants under SO(2) exposure. The mycorrhizal fungi colonization had no effect on the stomatal conductance. To our knowledge, this is the first finding of this sort.

  4. Strategies of ROS regulation and antioxidant defense during transition from C₃ to C₄ photosynthesis in the genus Flaveria under PEG-induced osmotic stress.

    PubMed

    Uzilday, Baris; Turkan, Ismail; Ozgur, Rengin; Sekmen, Askim H

    2014-01-01

    In the present study, we aimed to elucidate how strategies of reactive oxygen species (ROS) regulation and the antioxidant defense system changed during transition from C₃ to C₄ photosynthesis, by using the model genus Flaveria, which contains species belonging to different steps in C₄ evolution. For this reason, four Flaveria species that have different carboxylation mechanisms, Flaveria robusta (C₃), Flaveria anomala (C₃-C₄), Flaveria brownii (C₄-like) and Flaveria bidentis (C₄), were used. Physiological (growth, relative water content (RWC), osmotic potential), and photosynthetical parameters (stomatal conductance (g(s)), assimilation rate (A), electron transport rate (ETR)), antioxidant defense enzymes (superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), glutathione reductases(GR)) and their isoenzymes, non-enzymatic antioxidant contents (ascorbate, glutathione), NADPH oxidase (NOX) activity, hydrogen peroxide (H₂O₂) content and lipid peroxidation levels (TBARS) were measured comparatively under polyethylene glycol (PEG 6000) induced osmotic stress. Under non-stressed conditions, there was a correlation only between CAT (decreasing), APX and GR (both increasing) and the type of carboxylation pathways through C₃ to C₄ in Flaveria species. However, they responded differently to PEG-induced osmotic stress in regards to antioxidant defense. The greatest increase in H₂O₂ and TBARS content was observed in C₃ F. robusta, while the least substantial increase was detected in C₄-like F. brownii and C₄ F. bidentis, suggesting that oxidative stress is more effectively countered in C₄-like and C₄ species. This was achieved by a better induced enzymatic defense in F. bidentis (increased SOD, CAT, POX, and APX activity) and non-enzymatic antioxidants in F. brownii. As a response to PEG-induced oxidative stress, changes in activities of isoenzymes and also isoenzymatic patterns were observed in all

  5. Hydrogen Sulfide Alleviates Postharvest Senescence of Grape by Modulating the Antioxidant Defenses.

    PubMed

    Ni, Zhi-Jing; Hu, Kang-Di; Song, Chang-Bing; Ma, Run-Hui; Li, Zhi-Rong; Zheng, Ji-Lian; Fu, Liu-Hui; Wei, Zhao-Jun; Zhang, Hua

    2016-01-01

    Hydrogen sulfide (H2S) has been identified as an important gaseous signal in plants. Here, we investigated the mechanism of H2S in alleviating postharvest senescence and rotting of Kyoho grape. Exogenous application of H2S released from 1.0 mM NaHS remarkably decreased the rotting and threshing rate of grape berries. H2S application also prevented the weight loss in grape clusters and inhibited the decreases in firmness, soluble solids, and titratable acidity in grape pulp during postharvest storage. The data of chlorophyll and carotenoid content suggested the role of H2S in preventing chlorophyll breakdown and carotenoid accumulation in both grape rachis and pulp. In comparison to water control, exogenous H2S application maintained significantly higher levels of ascorbic acid and flavonoid and total phenolics and reducing sugar and soluble protein in grape pulp. Meanwhile, H2S significantly reduced the accumulation of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2 (∙-)) in grape pulp. Further investigations showed that H2S enhanced the activities of antioxidant enzymes ascorbate peroxidase (APX) and catalase (CAT) and decreased those of lipoxygenase (LOX) in both grape peels and pulp. In all, we provided strong evidence that H2S effectively alleviated postharvest senescence and rotting of Kyoho grape by modulating antioxidant enzymes and attenuating lipid peroxidation.

  6. Effect of long term intake of aspartame on antioxidant defense status in liver.

    PubMed

    Abhilash, M; Paul, M V Sauganth; Varghese, Mathews V; Nair, R Harikumaran

    2011-06-01

    The present study evaluates the effect of long term intake of aspartame, the artificial sweetener, on liver antioxidant system and hepatocellular injury in animal model. Eighteen adult male Wistar rats, weighing 150-175 g, were randomly divided into three groups as follows: first group was given aspartame dissolved in water in a dose of 500 mg/kg b.wt.; the second group was given a dose of 1000 mg/kg b.wt.; and controls were given water freely. Rats that had received aspartame (1000 mg/kg b.wt.) in the drinking water for 180 days showed a significant increase in activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and γ-glutamyl transferase (GGT). The concentration of reduced glutathione (GSH) and the activity of glutathione peroxidase (GPx), and glutathione reductase (GR) were significantly reduced in the liver of rats that had received aspartame (1000 mg/kg b.wt.). Glutathione was significantly decreased in both the experimental groups. Histopathological examination revealed leukocyte infiltration in aspartame-treated rats (1000 mg/kg b.wt.). It can be concluded from these observations that long term consumption of aspartame leads to hepatocellular injury and alterations in liver antioxidant status mainly through glutathione dependent system.

  7. Strengthening of antioxidant defense by Azadirachta indica in alloxan-diabetic rat tissues

    PubMed Central

    Shailey, Sweta; Basir, Seemi Farhat

    2012-01-01

    Background: Azadirachta indica has been reported to correct altered glycaemia in diabetes. Objective: The aqueous extract of A. indica leaf and bark has been evaluated for its effect on antioxidant status of alloxan diabetic rats and compared with insulin treatment. Materials and Methods: The oral effective dose of A. indica leaf (500 mg/kg body weight) and A. indica bark (100 mg/kg body weight) were given once daily for 21 days to separate groups of diabetic rats. At the end of the experimental period blood glucose level and activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G-6-PD), and membrane lipid peroxidation were determined in different fractions of liver and kidney tissues. Results: Diabetic rats showed high blood glucose (P<0.01), increased level of malondialdehyde (P<0.05) and a significant decrease in the activity of antioxidant enzymes. Treatment with insulin, A. indica leaf extract (AILE), and A. indica bark extract (AIBE) restored the above altered parameters close to the control ones. Conclusions: Both AILE and AIBE were found significantly effective in reducing hyperglycemia-induced oxidative stress. The findings suggest further investigations for the possible use of A. indica as alternative medicine to prevent long-term complications of diabetes. PMID:23125509

  8. Hydrogen Sulfide Alleviates Postharvest Senescence of Grape by Modulating the Antioxidant Defenses

    PubMed Central

    Ni, Zhi-Jing; Hu, Kang-Di; Song, Chang-Bing; Ma, Run-Hui; Li, Zhi-Rong; Zheng, Ji-Lian; Fu, Liu-Hui

    2016-01-01

    Hydrogen sulfide (H2S) has been identified as an important gaseous signal in plants. Here, we investigated the mechanism of H2S in alleviating postharvest senescence and rotting of Kyoho grape. Exogenous application of H2S released from 1.0 mM NaHS remarkably decreased the rotting and threshing rate of grape berries. H2S application also prevented the weight loss in grape clusters and inhibited the decreases in firmness, soluble solids, and titratable acidity in grape pulp during postharvest storage. The data of chlorophyll and carotenoid content suggested the role of H2S in preventing chlorophyll breakdown and carotenoid accumulation in both grape rachis and pulp. In comparison to water control, exogenous H2S application maintained significantly higher levels of ascorbic acid and flavonoid and total phenolics and reducing sugar and soluble protein in grape pulp. Meanwhile, H2S significantly reduced the accumulation of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2∙−) in grape pulp. Further investigations showed that H2S enhanced the activities of antioxidant enzymes ascorbate peroxidase (APX) and catalase (CAT) and decreased those of lipoxygenase (LOX) in both grape peels and pulp. In all, we provided strong evidence that H2S effectively alleviated postharvest senescence and rotting of Kyoho grape by modulating antioxidant enzymes and attenuating lipid peroxidation. PMID:27594971

  9. Effect of heavy metals on growth response and antioxidant defense protection in Bacillus cereus.

    PubMed

    Behera, Madhumita; Dandapat, Jagneshwar; Rath, Chandi Charan

    2014-11-01

    Bacterial cells in aerobic environment generate reactive oxygen species which may lead to oxidative stress, induced by a wide range of environmental factors including heavy metals. In the present context an attempt has been made to determine the toxic impact of cadmium and copper on growth performance, oxidative stress, and relative level of antioxidant protection in Bacillus cereus. Outcome of this study suggests that both the metal ions depleted the growth rate in this organism with respect to time and concentration of the metal ions. CdCl2 exposure induced extracellular glutathione (GSH) production, whereas, its level was declined in response to CuSO4. Superoxide dismutase (SOD) activity and hydrogen peroxide (H2 O2 ) content was elevated under CdCl2 stress but the activity of catalase (CAT) was inhibited. In contrast, incubation of bacteria with CuSO4 exhibited decreased SOD activity with concomitant rise in CAT activity and H2 O2 content. We also observed elevation of intracellular GSH level in this bacteria following supplementation of N-acetyl cysteine (NAC) in the medium. Overall findings of this study indicated differential toxicity of CdCl2 and CuSO4 in inducing oxidative stress, depleting growth rate and the possible involvement of GSH and CAT in adaptive antioxidant response.

  10. Antioxidant defense and apoptotic effectors in ascorbic acid and β-glycerophosphate-induced osteoblastic differentiation.

    PubMed

    Chaves Neto, Antonio Hernandes; Machado, Daisy; Yano, Cláudia Lumy; Ferreira, Carmen Veríssima

    2011-01-01

    MC3T3-E1 cells grown in the presence of ascorbic acid and β-glycerophosphate (AA/β-GP) express alkaline phosphatase and produce an extensive collagenous extracellular matrix. Differentiated MC3T3-E1 cells are more sensitive to hydrogen peroxide-induced oxidative stress than undifferentiated cells. In this study, we compared the profile of antioxidant enzymes and molecular markers of apoptosis in undifferentiated and differentiated MC3T3-E1 cells (cell differentiation was induced by treatment with AA/β-GP). Differentiated osteoblasts showed lower expression and activity of catalase, glutathione S-transferase and glutathione peroxidase. The total superoxide dismutase activity and the expression of Cu/Zn superoxide dismutase were also lower, while the expression of Mn superoxide dismutase was higher in differentiated osteoblasts. The level of malondialdehyde, a widely used marker for oxidative stress, was lower in the AA/β-GP group compared with control cells, but this difference was not significant. Western blotting showed that treatment with AA/β-GP increased the Bax/Bcl-2 ratio used as an index of cellular vulnerability to apoptosis. In addition, the activities of caspases 3, 8 and 9 and cleaved poly (ADP) ribose polymerase were significantly higher in differentiated cells. These findings provide new insights into how changes in the activities of major antioxidant enzymes and in the signaling pathways associated with apoptosis may influence the susceptibility of bone cells to oxidative stress.

  11. Changes in antioxidant defense status in hypercholesterolemic rats treated with Ajuga iva.

    PubMed

    Bouderbala, S; Lamri-Senhadji, M; Prost, J; Lacaille-Dubois, M A; Bouchenak, M

    2008-06-01

    The aim of the study was to investigate the effect of aqueous extract of Ajuga iva (Ai) on serum and tissues lipid peroxidation as well as antioxidant enzymes activities in red blood cells (RBC) and tissues, in high hypercholesterolemic rats (HC). Male Wistar rats (n=12) were fed on 1% cholesterol-enriched diet for 15d. After this adaptation phase, hypercholesterolemic rats (total cholesterol=6.5+/-0.6mol/l) were divided into two groups fed the same diet and treated or not with Ai for 15d. Thiobarbituric acid reactive substances (TBARS) concentrations in serum, LDL-HDL(1), HDL(2) and HDL(3) were respectively, 5-, 7.8-, 2.3- and 5-fold lower in Ai treated than untreated hypercholesterolemic groups. TBARS concentrations were 1.4-fold lower in heart and 2.8-fold higher in kidney in Ai-HC treated than untreated HC group. Superoxide dismutase activity was respectively, 1.2- and 1.4-fold higher in RBC and muscle in Ai treated than untreated group. In RBC, Ajuga iva treatment enhanced glutathione peroxidase (GSH-Px) (+9%) and glutathione reductase (GSSH-Red) (+12%) in Ai-HC treated than untreated HC group. GSSH-Red activity was 1.4- and 1.5-fold higher in adipose tissue and heart, respectively and 3.7-fold lower in kidney in Ai treated than untreated group. Liver catalase activity was 1.6-fold higher in Ai treated than untreated group. Adipose tissue and muscle total glutathione content represented in Ai treated group 35% and 36% of the value noted in untreated group. Nitric oxide values of liver, adipose tissue and heart were 3.3-, 2.5- and 3.4-fold higher in Ai-HC than HC group. Ajuga iva treatment enhanced alpha-tocopherol contents (+25%) in Ai treated than untreated group. In conclusion, Ajuga iva treatment is more effective to improve the antioxidant capacity of RBC than that of tissues. Indeed, Ai is able to reduce the oxidative stress in hypercholesterolemic rats by increasing the antioxidant enzymes activity.

  12. Effect of chromium (VI) exposure on antioxidant defense status and trace element homeostasis in acute experiment in rat.

    PubMed

    Kotyzová, Dana; Hodková, Anna; Bludovská, Monika; Eybl, Vladislav

    2015-11-01

    Occupational exposure to hexavalent chromium (Cr(VI)) compounds is of concern in many Cr-related industries and their surrounding environment. Cr(VI) is a proven toxin and carcinogen. The Cr(VI) compounds are easily absorbed, can diffuse across cell membranes, and have strong oxidative potential. Despite intensive studies of Cr(VI) pro-oxidative effects, limited data exist on the influence of Cr(VI) on selenoenzymes thioredoxin reductase (TrxR) and glutathione peroxidase (GPx)-important components of antioxidant defense system. This study investigates the effect of Cr(VI) exposure on antioxidant defense status, with focus on these selenoenzymes, and on trace element homeostasis in an acute experiment in rat. Male Wistar rats (130-140g) were assigned to two groups of 8 animals: I. control; and II. Cr(VI) treated. The animals in Cr(VI) group were administered a single dose of K2Cr2O7 (20 mg /kg, intraperitoneally (ip)). The control group received saline solution. After 24 h, the animals were sacrificed and the liver and kidneys were examined for lipid peroxidation (LP; thiobarbituric acid reactive substances (TBARS) concentration), the level of reduced glutathione (GSH) and the activities of GPx-1, TrxR-1, and glutathione reductase (GR). Samples of tissues were also used to estimate Cr accumulation and alterations in zinc, copper, and iron levels. The acute Cr(VI) exposure caused an increase in both hepatic and renal LP (by 70%, p < 0.01 and by 15%, p < 0.05, respectively), increased hepatic GSH level and GPx-1 activity, and decreased renal GPx-1 activity. The activity of GR was not changed. A significant inhibitory effect of Cr(VI) was found on TrxR-1 activity in both the liver and the kidneys. The ability of Cr(VI) to cause TrxR inhibition could contribute to its cytotoxic effects. Further investigation of oxidative responses in different in vivo models may enable the development of strategies to protect against Cr(VI) oxidative damage.

  13. Salicylic acid mediates antioxidant defense system and ABA pathway related gene expression in Oryza sativa against quinclorac toxicity.

    PubMed

    Wang, Jian; Lv, Mengting; Islam, Faisal; Gill, Rafaqat A; Yang, Chong; Ali, Basharat; Yan, Guijun; Zhou, Weijun

    2016-11-01

    The auxin herbicide quinclorac is widely used for controlling weeds in transplanted and direct-seeded rice fields. However, its phytotoxic responses on rice are still unknown. Therefore, in the present investigation we studied the effects of different concentrations (0, 0.1 and 0.5g/L) of quinclorac herbicide on the physiological and biochemical changes of two rice cultivars (XS 134 and ZJ 88) and further analyzed the ameliorating role of salicylic acid (SA) on quinclorac toxicity in rice plants. The results revealed that exogenous application of SA significantly increased plant biomass and total chlorophyll contents in herbicide stressed plants. The lipid peroxidation and ROS (H2O2, O2(-.), (-)OH) production were significantly increased in roots and leaves of both rice cultivars under quinclorac stress, demonstrating an oxidative burst in rice plants. Whereas, application of SA significantly lowered ROS contents under quinclorac stress. Further, exogenous SA treatment significantly modulated antioxidant enzymes and enhanced GSH concentration in stress plants. Anatomical observations of leaf and root revealed that herbicide affected internal structures, while SA played a vital role in protection from toxic effects. Expression analysis of stress hormone ABA genes (OsABA8oxs, OsNCEDs) revealed that quinclorac application enhanced stress condition in cultivar ZJ 88, while SA treatment downregulated ABA genes more in cultivar XS 134, which correlated with the enhanced tolerance to quinclorac induced oxidative stress in this cultivar. The present study delineated that SA played a critical role under quinclorac stress in both rice cultivars by regulating antioxidant defense system, reducing ROS formation and preventing the degradation of internal cell organelles.

  14. Dietary Curcumin Increases Antioxidant Defenses in Lung, Ameliorates Radiation-Induced Pulmonary Fibrosis, and Improves Survival in Mice

    PubMed Central

    Lee, James C.; Kinniry, Paul A.; Arguiri, Evguenia; Serota, Matthew; Kanterakis, Stathis; Chatterjee, Shampa; Solomides, Charalambos C.; Javvadi, Prashanthi; Koumenis, Constantinos; Cengel, Keith A.; Christofidou-Solomidou, Melpo

    2010-01-01

    The effectiveness of lung radiotherapy is limited by radiation tolerance of normal tissues and by the intrinsic radiosensitivity of lung cancer cells. The chemopreventive agent curcumin has known antioxidant and tumor cell radiosensitizing properties. Its usefulness in preventing radiation-induced pneumonopathy has not been tested previously. We evaluated dietary curcumin in radiation-induced pneumonopathy and lung tumor regression in a murine model. Mice were given 1%or 5%(w/w) dietary curcumin or control diet prior to irradiation and for the duration of the experiment. Lungs were evaluated at 3 weeks after irradiation for acute lung injury and inflammation by evaluating bronchoalveolar lavage (BAL) fluid content for proteins, neutrophils and at 4 months for pulmonary fibrosis. In a separate series of experiments, an orthotopic model of lung cancer using intravenously injected Lewis lung carcinoma (LLC) cells was used to exclude possible tumor radioprotection by dietary curcumin. In vitro, curcumin boosted antioxidant defenses by increasing heme oxygenase 1 (HO-1) levels in primary lung endothelial and fibroblast cells and blocked radiation-induced generation of reactive oxygen species (ROS). Dietary curcumin significantly increased HO-1 in lungs as early as after 1 week of feeding, coinciding with a steady-state level of curcumin in plasma. Although both 1% and 5% w/w dietary curcumin exerted physiological changes in lung tissues by significantly decreasing LPS-induced TNF-α production in lungs, only 5%dietary curcumin significantly improved survival of mice after irradiation and decreased radiation-induced lung fibrosis. Importantly, dietary curcumin did not protect LLC pulmonary metastases from radiation killing. Thus dietary curcumin ameliorates radiation-induced pulmonary fibrosis and increases mouse survival while not impairing tumor cell killing by radiation. PMID:20426658

  15. Heat-shock response and antioxidant defense during air exposure in Patagonian shallow-water limpets from different climatic habitats.

    PubMed

    Pöhlmann, Kevin; Koenigstein, Stefan; Alter, Katharina; Abele, Doris; Held, Christoph

    2011-11-01

    Climate warming involves not only a rise of air temperature means, but also more frequent heat waves in many regions on earth, and is predicted to intensify physiological stress especially in extremely changeable habitats like the intertidal. We investigated the heat-shock response (HSR) and enzymatic antioxidant defense levels of Patagonian shallow-water limpets, adapted to distinct tidal exposure conditions in the sub- and intertidal. Limpets were sampled in the temperate Northern Patagonia and the subpolar Magellan region. Expression levels of two Hsp70 genes and activities of the antioxidants superoxide dismutase (SOD) and catalase (CAT) were measured in submerged and 2- and 12-h air-exposed specimens. Air-exposed Patagonian limpets showed a tiered HSR increasing from South to North on the latitudinal gradient and from high to low shore levels on a tidal gradient. SOD activities in the Magellan region correlated with the tidal rhythm and were higher after 2 and 12 h when the tide was low at the experimental site compared to the 6 h value taken at high tide. This pattern was observed in intertidal and subtidal specimens, although subtidal individuals are little affected by tides. Our study shows that long-term thermal adaptation shapes the HSR in limpets, while the oxidative stress response is linked to the tidal rhythm. Close to the warm border of their distribution range, energy expenses to cope with stress might become overwhelming and represent one cause why the limpets are unable to colonize the shallow intertidal zone.

  16. Combined herbicide and saline stress differentially modulates hormonal regulation and antioxidant defense system in Oryza sativa cultivars.

    PubMed

    Islam, Faisal; Ali, Basharat; Wang, Jian; Farooq, Muhammad A; Gill, Rafaqat A; Ali, Shafaqat; Wang, Danying; Zhou, Weijun

    2016-10-01

    Plants are simultaneously exposed to a combination of biotic and abiotic stresses in field conditions. Crops respond to the combined stress in a unique way which cannot be understood by extrapolating the results of individual stress. In the present study, effects of individual and combined stress of herbicide (2,4-dichlorophenoxyacetic acid) and salinity (NaCl) on two Oryza sativa cultivars (ZJ 88 and XS 134) were investigated. Both herbicide and saline stress affected the plant growth differentially and produced oxidative stress in rice cultivars. Interestingly, the combination of herbicide and salinity showed a significant protection to both rice cultivars by reducing ROS (H2O2, O2(-)) and lipid peroxidation through modulation of enzymatic (SOD, POD, CAT and APX) and non-enzymatic (TSP, sugars, phenolic and proline) antioxidants. In addition, active regulation of transcript levels of genes encoding Na(+) and K(+) (OsHKT1;5, OsLti6a,b, OsHKT2;1, OsSOS1, OsCNGC1, OsNHX1 and OsAKT1) transporter proteins reduced sodium and enhanced potassium accumulation under combined stress, resulted a better growth and ionic homeostasis in both rice cultivars. The production of ABA and IAA was significantly higher in cultivar XS 134 compared to cultivar ZJ 88 under control conditions. However, combined herbicide and saline stress enhanced the accumulation of phytohormones (IAA and ABA) and transcription of ethylene in cultivar ZJ 88, which might be one of the factors responsible for poor salt tolerance in sensitive cultivar. These findings indicated that herbicide application under saline stress confers tolerance to salinity in rice cultivars, likely by reducing oxidative damage, modulating mineral absorption, upgradation of antioxidant defense and by dynamic regulation of key genes involved in Na(+) and K(+) homeostasis in plants.

  17. Effects of azinphos-methyl exposure on enzymatic and non-enzymatic antioxidant defenses in Biomphalaria glabrata and Lumbriculus variegatus.

    PubMed

    Kristoff, Gisela; Verrengia Guerrero, Noemí R; Cochón, Adriana C

    2008-07-01

    Azinphos-methyl is an organophosphate insecticide used for pest control on a number of food crops in many parts of the world. The oligochaete Lumbriculus variegatus and pigmented and non-pigmented specimens of the gastropod Biomphalaria glabrata are freshwater invertebrates that have been recommended for contamination studies. Recently, it has been shown that L. variegatus worms exhibit a higher cholinesterase (ChE) activity and a greater sensitivity to in vivo ChE inhibition by azinphos-methyl than pigmented B. glabrata snails. The aims of the present study were (1) to investigate if, in addition to its anticholinesterase action, azinphos-methyl has also pro-oxidant activity in L. variegatus and B. glabrata, and (2) to examine if species that are highly susceptible to the neurotoxic effects of organophosphates also suffer a greater degree of oxidative stress. Therefore, total glutathione (t-GSH) levels and activities of cholinesterase (ChE), superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and glucose 6-phosphate dehydrogenase (G6PDH) were measured in the whole body soft tissue of organisms exposed for 48 and 96 h to a level of azinphos-methyl that produces 50% of inhibition on ChE. Results showed different patterns of antioxidant responses between the gastropods and the oligochaetes, and even between the two phenotypes of gastropods: (1) in exposed L. variegatus t-GSH levels increased and CAT and SOD activities decreased with respect to control organisms, (2) in pigmented gastropods, SOD decreased while CAT transiently diminished, and (3) in non-pigmented gastropods, SOD activity showed a biphasic response. GST and G6PDH were not altered by azinphos-methyl exposure. Of note, t-GSH levels were 4-fold times higher in L. variegatus than in both phenotypes of B. glabrata. This may suggest that GSH could play a more important role in antioxidant defense in L. variegatus than in B. glabrata.

  18. Selenium pretreatment upregulates the antioxidant defense and methylglyoxal detoxification system and confers enhanced tolerance to drought stress in rapeseed seedlings.

    PubMed

    Hasanuzzaman, Mirza; Fujita, Masayuki

    2011-12-01

    In order to observe the possible regulatory role of selenium (Se) in relation to the changes in ascorbate (AsA) glutathione (GSH) levels and to the activities of antioxidant and glyoxalase pathway enzymes, rapeseed (Brassica napus) seedlings were grown in Petri dishes. A set of 10-day-old seedlings was pretreated with 25 μM Se (Sodium selenate) for 48 h. Two levels of drought stress (10% and 20% PEG) were imposed separately as well as on Se-pretreated seedlings, which were grown for another 48 h. Drought stress, at any level, caused a significant increase in GSH and glutathione disulfide (GSSG) content; however, the AsA content increased only under mild stress. The activity of ascorbate peroxidase (APX) was not affected by drought stress. The monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR) activity increased only under mild stress (10% PEG). The activity of dehydroascorbate reductase (DHAR), glutathione S-transferase (GST), glutathione peroxidase (GPX), and glyoxalase I (Gly I) activity significantly increased under any level of drought stress, while catalase (CAT) and glyoxalase II (Gly II) activity decreased. A sharp increase in hydrogen peroxide (H(2)O(2)) and lipid peroxidation (MDA content) was induced by drought stress. On the other hand, Se-pretreated seedlings exposed to drought stress showed a rise in AsA and GSH content, maintained a high GSH/GSSG ratio, and evidenced increased activities of APX, DHAR, MDHAR, GR, GST, GPX, CAT, Gly I, and Gly II as compared with the drought-stressed plants without Se. These seedlings showed a concomitant decrease in GSSG content, H(2)O(2), and the level of lipid peroxidation. The results indicate that the exogenous application of Se increased the tolerance of the plants to drought-induced oxidative damage by enhancing their antioxidant defense and methylglyoxal detoxification systems.

  19. Arsenic induced modulation of antioxidative defense system and brassinosteroids in Brassica juncea L.

    PubMed

    Kanwar, Mukesh Kumar; Poonam; Bhardwaj, Renu

    2015-05-01

    Brassica juncea (Indian mustard) L. plants were exposed to different concentrations (0.0, 0.1, 0.2 and 0.3mM) of arsenic (V) and harvested after 30 and 60 days of sowing for the analysis of growth parameters, metal uptake, brassinosteroids (BRs) synthesis and oxidative stress markers. As (V) significantly hampered the growth of B. juncea plants and triggered the modulations of various stress markers like proteins, antioxidative enzymes (SOD, CAT, POD, APX, GR, MDHAR and DHAR) and MDA content. Furthermore, As (V) induced the synthesis of 4 BRs, castasterone, teasterone, 24-epibrassinolide, and typhasterol, which were isolated and characterized by gas chromatography-mass spectrometry (GC-MS). The study further highlig5895hted the significant uptake of arsenic ions by mustard plants.

  20. Hypoxia tolerance and antioxidant defense system of juvenile jumbo squids in oxygen minimum zones

    NASA Astrophysics Data System (ADS)

    Trübenbach, Katja; Teixeira, Tatiana; Diniz, Mário; Rosa, Rui

    2013-10-01

    Jumbo squid (Dosidicus gigas) is a large oceanic squid endemic off the Eastern Tropical Pacific that undertakes diel vertical migrations into mesopelagic oxygen minimum zones. One of the expected physiological effects of such migration is the generation of reactive oxygen species (ROS) at the surface, promoted by the transition between hypoxia and reoxygenation states. The aim of this study was to investigate the energy expenditure rates and the antioxidant stress strategies of juvenile D. gigas under normoxia and hypoxia, namely by quantifying oxygen consumption rates, antioxidant enzyme activities [including superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST)], heat shock protein expression (Hsp70/Hsc70), and lipid peroxidation [malondialdehyde (MDA) levels]. A high significant decrease (68%) in squid's metabolic rates was observed during hypoxia (p<0.05). This process of metabolic suppression was followed by a significant increase in Hsp70/Hsc70 expression (p<0.05), which may be interpreted as a strategy to prevent post-hypoxic oxidative damage during the squid's night upwards migration to the surface ocean. On the other hand, in normoxia, the higher SOD and CAT activities seemed to be a strategy to cope with the reoxygenation process, and may constitute an integrated stress response at shallower depths. GST activity and MDA concentrations did not change significantly from normoxia to hypoxia (p>0.05), with the latter indicating no enhancement of lipid peroxidation (i.e. cellular damage) at the warmer and normoxic surface waters. The understanding of such physiological strategies that are linked to oxygen deprivation and reoxygenation phases may provide valuable information about how this species is quickly responding to the impacts of environmental stressors coupled with global climate change.

  1. Amelioration of Heat Stress Induced Disturbances of Antioxidant Defense System in Chicken by Brahma Rasayana

    PubMed Central

    Rekha, P. S.; Sujatha, K. S.

    2008-01-01

    Since the range of comfort zone or thermo neutral zone of domestic chickens is narrow, they become easily susceptible to heat and cold environmental stress. We evaluated Brahma Rasayana (BR) supplementation on concentrations of certain oxidative stress markers associated with heat stress. A total of 48 egg type male chickens of local strain were divided into six groups (n = 8) for the study. Three groups were fed with BR orally at the rate of 2 g/kg bw daily for 10 days prior to and during the period of experiment. Two of the four groups that were exposed to heat stress (HST i.e. to a temperature of 40 ± 1°C and relative humidity of 80 ± 5% in an environmental chamber) for 4 h daily for 5 or 10 days, received BR orally. The other two groups remained as BR treated and untreated non-heat stressed (NHST) controls. There was a significant (P < 0.05) increase in the activities of antioxidant enzymes in blood such as catalase (CAT) and superoxide dismutase (SOD), as well as liver CAT, glutathione peroxidase (GPX) and glutathione reductase (GR) in NHST-BR treated and HST-BR treated (both 5 and 10 days) chickens when compared with untreated controls. A great deal of significant (P < 0.05) variations were seen in serum and liver reduced glutathione (GSH) concentration in NHST-BR treated and HST-BR treated (both 5 and 10 days) chickens. Serum and liver lipid peroxidation levels were found to be significantly (P < 0.05) higher in HST-untreated (both 5 and 10 days) chickens when compared with other groups. Thus BR supplementation during HST brings about enhanced action of enzymatic and non-enzymatic antioxidants, which nullified the undesired side effects of free radicals that are generated during HST. PMID:18317552

  2. Hypometabolism, antioxidant defenses and free radical metabolism in the pulmonate land snail Helix aspersa.

    PubMed

    Ramos-Vasconcelos, Gabriella R; Hermes-Lima, Marcelo

    2003-02-01

    The aim of this work was to evaluate the effect of a cycle of estivation and awakening on free radical metabolism in selected organs of the land snail Helix aspersa. Estivation for 20 days induced a 4.9- and 1.8-fold increase in selenium-dependent glutathione peroxidase activity (Se-GPX) and in total glutathione levels (GSH-eq), respectively, in hepatopancreas when compared to activity in active animals 24 h after awakening. Foot muscle Se-GPX activity was also increased 3.9-fold during estivation, whereas GSH-eq did not vary. The activities of other antioxidant enzymes (catalase, superoxide dismutase, glutathione reductase and glutathione S-transferase) and glucose 6-phosphate dehydrogenase were unchanged in both organs. After 15 min of awakening, the glutathione disulphide (GSSG)/GSH-eq ratio increased significantly by 55% in hepatopancreas, slowly returning to the levels observed during estivation. The higher GSSG/GSH-eq ratio may be caused by increased formation of reactive oxygen species (ROS) during awakening. The levels of thiobarbituric acid reactive substances (TBARS) decreased from 49 to 30.7 nmol g(-1) wet mass in hepatopancreas after 5 min arousal and, after 30 min, TBARS rose significantly to 39.6 nmol g(-1) wet mass, gradually declining thereafter. The levels of lipid hydroperoxides in hepatopancreas and of carbonyl protein in foot muscle both decreased during awakening. The higher levels of products of free radical damage during estivation may have resulted from low levels of ROS formation associated with decreased rates of lipid hydroperoxide detoxification and oxidized protein turnover caused by metabolic depression. The regulation of the antioxidant system during hypometabolism may constitute a mechanism to minimize oxidative stress during cycles of estivation and awakening.

  3. Testosterone enhances functional recovery after stroke through promotion of antioxidant defenses, BDNF levels and neurogenesis in male rats.

    PubMed

    Fanaei, Hamed; Karimian, Seyed Morteza; Sadeghipour, Hamid Reza; Hassanzade, Gholamreza; Kasaeian, Amir; Attari, Fatemeh; Khayat, Samira; Ramezani, Vahid; Javadimehr, Mani

    2014-04-16

    It is reported that circulating testosterone levels decrease after cerebral ischemia. The aim of this study was to evaluate the effects of testosterone on oxidative stress, brain-derived neurotrophic factor (BDNF) levels, neurogenesis, histological damage and sensorimotor recovery in a castrated male rat model of focal cerebral ischemia. Animals were divided into four groups. For all animals, castrations were conducted 7 days before transient middle cerebral artery occlusion (MCAO) was done and cerebral ischemia was induced. The first group served as sham. Second was MCAO group and received vehicle only, third was MCAO group that was post-treated with testosterone and the fourth was MCAO group post-treated with testosterone and flutamide. Treatment only with testosterone significantly weakened oxidative stress and increased BDNF levels and sensorimotor recovery during a 10 days period. Rats receiving testosterone demonstrated a significant reduction in infarct volume and a significant increase in neurogenesis on 10th day after focal cerebral ischemia. Our results for the first time showed a potential advantageous effect of testosterone after cerebral ischemia in male rats, which was probably mediated by promoting antioxidant defenses, BDNF levels and neurogenesis.

  4. The Dual Role of Nrf2 in Nonalcoholic Fatty Liver Disease: Regulation of Antioxidant Defenses and Hepatic Lipid Metabolism.

    PubMed

    Chambel, Sílvia S; Santos-Gonçalves, Andreia; Duarte, Tiago L

    2015-01-01

    Nonalcoholic fatty liver disease (NAFLD) is a progressive liver disease with ever-growing incidence in the industrialized world. It starts with the simple accumulation of lipids in the hepatocyte and can progress to the more severe nonalcoholic steatohepatitis (NASH), which is associated with inflammation, fibrosis, and cirrhosis. There is increasing awareness that reactive oxygen species and electrophiles are implicated in the pathogenesis of NASH. Transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is a positive regulator of the expression of a battery of genes involved in the protection against oxidative/electrophilic stress. In rodents, Nrf2 is also known to participate in hepatic fatty acid metabolism, as a negative regulator of genes that promote hepatosteatosis. We review relevant evidence in the literature that these two mechanisms may contribute to the protective role of Nrf2 in the development of hepatic steatosis and in the progression to steatohepatitis, particularly in young animals. We propose that age may be a key to explain contradictory findings in the literature. In summary, Nrf2 mediates the crosstalk between lipid metabolism and antioxidant defense mechanisms in experimental models of NAFLD, and the nutritional or pharmacological induction of Nrf2 represents a promising potential new strategy for its prevention and treatment.

  5. Mycobacterium tuberculosis Thioredoxin Reductase Is Essential for Thiol Redox Homeostasis but Plays a Minor Role in Antioxidant Defense

    PubMed Central

    Lin, Kan; O'Brien, Kathryn M.; Trujillo, Carolina; Wang, Ruojun; Wallach, Joshua B.; Schnappinger, Dirk

    2016-01-01

    Mycobacterium tuberculosis (Mtb) must cope with exogenous oxidative stress imposed by the host. Unlike other antioxidant enzymes, Mtb’s thioredoxin reductase TrxB2 has been predicted to be essential not only to fight host defenses but also for in vitro growth. However, the specific physiological role of TrxB2 and its importance for Mtb pathogenesis remain undefined. Here we show that genetic inactivation of thioredoxin reductase perturbed several growth-essential processes, including sulfur and DNA metabolism and rapidly killed and lysed Mtb. Death was due to cidal thiol-specific oxidizing stress and prevented by a disulfide reductant. In contrast, thioredoxin reductase deficiency did not significantly increase susceptibility to oxidative and nitrosative stress. In vivo targeting TrxB2 eradicated Mtb during both acute and chronic phases of mouse infection. Deliberately leaky knockdown mutants identified the specificity of TrxB2 inhibitors and showed that partial inactivation of TrxB2 increased Mtb’s susceptibility to rifampicin. These studies reveal TrxB2 as essential thiol-reducing enzyme in Mtb in vitro and during infection, establish the value of targeting TrxB2, and provide tools to accelerate the development of TrxB2 inhibitors. PMID:27249779

  6. Drought resistance in rice seedlings conferred by seed priming : role of the anti-oxidant defense mechanisms.

    PubMed

    Goswami, Alakananda; Banerjee, Rahul; Raha, Sanghamitra

    2013-10-01

    Seed priming is a method by which seeds are subjected to different stress conditions to impart stress adaptation in seedlings germinating and growing under stressful situations. Drought stress is a major reason behind failure of crops. We studied the effects of hydropriming, dehydration priming (induced by PEG), and osmopriming (induced by NaCl and KH(2)PO(4)) on subsequent germination, growth and anti-oxidant defense mechanisms of 2-week-old rice seedlings under continuing dehydration stress. Unprimed seeds grown in PEG showed significantly lower germination and growth along with significantly higher reactive oxygen species (ROS) and lipid peroxidation levels. Among the priming methods, 5 % PEG priming was found to be the best in terms of germination and growth rate along with the lowest amount of ROS and lipid peroxidation (malondialdehyde [MDA]) values. MDA levels were reduced significantly by all of the priming methods. Hence, reduction of lipid peroxidation may be a key factor underlying the drought tolerance produced by the priming treatments. Glutathione peroxidase (GPX) activity seemed to bear an excellent correlation with oxidative stress resistance through seed priming. The PEG priming produced minimum peroxidative damage and superior germination and growth rate along with efficient GPX activity, overexpressed MnSOD and maintenance of HSP70 expression in normal as well as in drought condition. Therefore, in PEG-primed seeds the existence of robust protective mechanisms is definitely indicated.

  7. The Dual Role of Nrf2 in Nonalcoholic Fatty Liver Disease: Regulation of Antioxidant Defenses and Hepatic Lipid Metabolism

    PubMed Central

    Chambel, Sílvia S.; Santos-Gonçalves, Andreia; Duarte, Tiago L.

    2015-01-01

    Nonalcoholic fatty liver disease (NAFLD) is a progressive liver disease with ever-growing incidence in the industrialized world. It starts with the simple accumulation of lipids in the hepatocyte and can progress to the more severe nonalcoholic steatohepatitis (NASH), which is associated with inflammation, fibrosis, and cirrhosis. There is increasing awareness that reactive oxygen species and electrophiles are implicated in the pathogenesis of NASH. Transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is a positive regulator of the expression of a battery of genes involved in the protection against oxidative/electrophilic stress. In rodents, Nrf2 is also known to participate in hepatic fatty acid metabolism, as a negative regulator of genes that promote hepatosteatosis. We review relevant evidence in the literature that these two mechanisms may contribute to the protective role of Nrf2 in the development of hepatic steatosis and in the progression to steatohepatitis, particularly in young animals. We propose that age may be a key to explain contradictory findings in the literature. In summary, Nrf2 mediates the crosstalk between lipid metabolism and antioxidant defense mechanisms in experimental models of NAFLD, and the nutritional or pharmacological induction of Nrf2 represents a promising potential new strategy for its prevention and treatment. PMID:26120584

  8. Effect of Calendula officinalis Flower Extract on Acute Phase Proteins, Antioxidant Defense Mechanism and Granuloma Formation During Thermal Burns

    PubMed Central

    Chandran, Preethi K.; Kuttan, Ramadasan

    2008-01-01

    Effect of Calendula officinalis flower extract was investigated against experimentally induced thermal burns in rats. Burn injury was made on the shaven back of the rats under anesthesia and the animals were treated orally with different doses of the flower extract (20 mg, 100 mg and 200 mg/kg body weight). The animals treated with the extract showed significant improvement in healing when compared with the control untreated animals. The indicators of the wound healing such as collagen-hydroxyproline and hexosamine contents were significantly increased in the treated group indicating accelerated wound healing in the treated animals. The acute phase proteins—haptoglobin and orosomucoid which were increased due to burn injury were found to be decreased significantly in 200 mg/kg body weight extract treated animals. The antioxidant defense mechanism, which was decreased in the liver during burn injury, was found to be enhanced in treated animals. The lipid peroxidation was significantly lowered in the treated group when compared to control animals. Tissue damage marker enzymes- alkaline phosphatase, alanine and aspartate transaminases were significantly lowered in the treated groups in a dose dependant manner. The histopathological analyses of skin tissue also give the evidence of the increased healing potential of the extract after burn injury. PMID:18818737

  9. Alleviation of alcoholic liver injury by betaine involves an enhancement of antioxidant defense via regulation of sulfur amino acid metabolism.

    PubMed

    Jung, Young Suk; Kim, Sun Ju; Kwon, Do Young; Ahn, Chul Won; Kim, Young Soon; Choi, Dal Woong; Kim, Young Chul

    2013-12-01

    Previous studies suggested that the hepatoprotective activity of betaine is associated with its effects on sulfur amino acid metabolism. We examined the mechanism by which betaine prevents the progression of alcoholic liver injury and its therapeutic potential. Rats received a liquid ethanol diet for 6 wk. Ethanol consumption elevated serum triglyceride and TNFα levels, alanine aminotransferase and aspartate aminotransferase activities, and lipid accumulation in liver. The oxyradical scavenging capacity of liver was reduced, and expression of CD14, TNFα, COX-2, and iNOS mRNAs was induced markedly. These ethanol-induced changes were all inhibited effectively by betaine supplementation. Hepatic S-adenosylmethionine, cysteine, and glutathione levels, reduced in the ethanol-fed rats, were increased by betaine supplementation. Methionine adenosyltransferase and cystathionine γ-lyase were induced, but cysteine dioxygenase was down-regulated, which appeared to account for the increment in cysteine availability for glutathione synthesis in the rats supplemented with betaine. Betaine supplementation for the final 2 wk of ethanol intake resulted in a similar degree of hepatoprotection, revealing its potential therapeutic value in alcoholic liver. It is concluded that the protective effects of betaine against alcoholic liver injury may be attributed to the fortification of antioxidant defense via improvement of impaired sulfur amino acid metabolism.

  10. Prooxidative effects of aspartame on antioxidant defense status in erythrocytes of rats.

    PubMed

    Prokic, Marko D; Paunovic, Milica G; Matic, Milos M; Djordjevic, Natasa Z; Ognjanovic, Branka I; Stajn, Andras S; Saicic, Zorica S

    2014-12-01

    Since aspartame (L-aspartyl-L-phenylalanine methyl ester, ASP) is one of the most widely used artificial sweeteners, the aim of the present study was to investigate its effects on serum glucose and lipid levels as well as its effects on oxidative/antioxidative status in erythrocytes of rats. The experiment included two groups of animals: the control group was administered with water only, while the experimental group was orally administered with ASP (40 mg/kg b.w.) daily, for a period of six weeks. When compared with the control group, the group administrated with ASP indicated higher values of serum glucose, cholesterol and triglycerides. Significantly increased concentrations of superoxide anion (O2 .-), hydrogen peroxide (H2O2), peroxynitrite (?N??-) and lipid peroxides (LPO) were recorded in the erythrocytes of ASP treated group in comparison to the control group. In the course of chronic ASP administration, the following was observed: the concentration of reduced glutathione (GSH) and the activity of catalase (CAT) increased. Thus, these findings suggest that long-term consumption of ASP leads to hyperglycemia and hyperlipidemia, as well as to oxidative stress in erythrocytes.

  11. Heavy Metals and Human Health: Mechanistic Insight into Toxicity and Counter Defense System of Antioxidants

    PubMed Central

    Jan, Arif Tasleem; Azam, Mudsser; Siddiqui, Kehkashan; Ali, Arif; Choi, Inho; Haq, Qazi Mohd. Rizwanul

    2015-01-01

    Heavy metals, which have widespread environmental distribution and originate from natural and anthropogenic sources, are common environmental pollutants. In recent decades, their contamination has increased dramatically because of continuous discharge in sewage and untreated industrial effluents. Because they are non-degradable, they persist in the environment; accordingly, they have received a great deal of attention owing to their potential health and environmental risks. Although the toxic effects of metals depend on the forms and routes of exposure, interruptions of intracellular homeostasis include damage to lipids, proteins, enzymes and DNA via the production of free radicals. Following exposure to heavy metals, their metabolism and subsequent excretion from the body depends on the presence of antioxidants (glutathione, α-tocopherol, ascorbate, etc.) associated with the quenching of free radicals by suspending the activity of enzymes (catalase, peroxidase, and superoxide dismutase). Therefore, this review was written to provide a deep understanding of the mechanisms involved in eliciting their toxicity in order to highlight the necessity for development of strategies to decrease exposure to these metals, as well as to identify substances that contribute significantly to overcome their hazardous effects within the body of living organisms. PMID:26690422

  12. Heavy Metals and Human Health: Mechanistic Insight into Toxicity and Counter Defense System of Antioxidants.

    PubMed

    Jan, Arif Tasleem; Azam, Mudsser; Siddiqui, Kehkashan; Ali, Arif; Choi, Inho; Haq, Qazi Mohd Rizwanul

    2015-12-10

    Heavy metals, which have widespread environmental distribution and originate from natural and anthropogenic sources, are common environmental pollutants. In recent decades, their contamination has increased dramatically because of continuous discharge in sewage and untreated industrial effluents. Because they are non-degradable, they persist in the environment; accordingly, they have received a great deal of attention owing to their potential health and environmental risks. Although the toxic effects of metals depend on the forms and routes of exposure, interruptions of intracellular homeostasis include damage to lipids, proteins, enzymes and DNA via the production of free radicals. Following exposure to heavy metals, their metabolism and subsequent excretion from the body depends on the presence of antioxidants (glutathione, α-tocopherol, ascorbate, etc.) associated with the quenching of free radicals by suspending the activity of enzymes (catalase, peroxidase, and superoxide dismutase). Therefore, this review was written to provide a deep understanding of the mechanisms involved in eliciting their toxicity in order to highlight the necessity for development of strategies to decrease exposure to these metals, as well as to identify substances that contribute significantly to overcome their hazardous effects within the body of living organisms.

  13. Effect of low doses of herbicide paraquat on antioxidant defense in Drosophila.

    PubMed

    Krůček, Tomáš; Korandová, Michala; Šerý, Michal; Frydrychová, Radmila Čapková; Krůček, Tomáš; Korandová, Michala; Szakosová, Klára

    2015-04-01

    Despite a high toxicity, paraquat is one of the most widely used herbicides in the world. Our study evaluated the effect of paraquat exposure on antioxidant response and locomotion activity in Drosophila melanogaster. We examined the enzymatic activity of superoxide dismutase (SOD) and catalase, and the transcript levels of both enzymes. Flies were exposed to a wide range of paraquat concentrations (0.25 μM to 25 mM) for 12 h. SOD, at both transcript and enzymatic levels, revealed a biphasic dose-response curve with the peak at 2.5 μM paraquat. A similar dose-response curve was observed at transcript levels of catalase. Males revealed higher susceptibility to paraquat exposure, displaying higher lethality, increased levels of SOD activity, and increased peroxide levels than in females. We found that the exposure of females to 2.5 μM paraquat leads to an increase in locomotion activity. Because susceptibility to paraquat was enhanced by mating, the study supports the hypothesis of elevation of stress sensitivity as a physiological cost of reproduction.

  14. Redox-dependent induction of antioxidant defenses by phenolic diterpenes confers stress tolerance in normal human skin fibroblasts: Insights on replicative senescence.

    PubMed

    Carvalho, Ana C; Gomes, Andreia C; Pereira-Wilson, Cristina; Lima, Cristovao F

    2015-06-01

    Mild stress-induced hormesis represents a promising strategy for targeting the age-related accumulation of molecular damage and, therefore, for preventing diseases and achieving healthy aging. Fruits, vegetables, and spices contain a wide variety of hormetic phytochemicals, which may explain the beneficial health effects associated with the consumption of these dietary components. In the present study, the induction of cellular antioxidant defenses by the phenolic diterpenes carnosic acid (CA) and carnosol (CS) were studied in normal human skin fibroblasts, and insights into the aging process at the cellular level investigated. We observed that CA and CS induced several cytoprotective enzymes and antioxidant defenses in human fibroblasts, whose induction was dependent on the cellular redox state for CS and associated with Nrf2 signaling for both compounds. The stress response elicited by preincubation with CS conferred a cytoprotective action against a following oxidant challenge with tert-butyl hydroperoxide, confirming its hormetic effect. Preincubation of normal fibroblasts with CS also protected against hydrogen peroxide-induced premature senescence. Furthermore, cultivation of middle passage normal human skin fibroblasts in the presence of CS ameliorated the physiological state of cells during replicative senescence. Our results support the view that mild stress-induced antioxidant defenses by CS can confer stress tolerance in normal cells and may have important implications in the promotion of healthy aging.

  15. EROD activity and antioxidant defenses of sea bass (Dicentrarchus labrax) after an in vivo chronic hydrocarbon pollution followed by a post-exposure period.

    PubMed

    Danion, Morgane; Le Floch, Stéphane; Lamour, François; Quentel, Claire

    2014-12-01

    Chronic concentrations of polycyclic aromatic hydrocarbons (PAHs) have been commonly detected in international estuaries ecosystems. Reliable indicators still need to be found in order to properly assess the impact of PAHs in fish. After an in vivo chronic exposure to hydrocarbons, the enzymatic activity of 7-ethoxyresorufin O-deethylase (EROD) and the antioxidant defense system were assessed in sea bass, Dicentrarchus labrax. A total of 45 fish were exposed to the water-soluble fraction of Arabian crude oil, similar to a complex pollution by hydrocarbons chronically observed in situ, while 45 other control fish sustained the same experimental conditions in clean seawater. Fish samples were made after a 21-day exposure period and after a 15-day recovery period in clean fresh water. Throughout the experiment, liver EROD activity was significantly higher in contaminated fish than in control fish. In addition, nonenzymatic (total glutathione) and enzymatic (GPx, SOD, and CAT) antioxidant defense parameters measured in liver were not significantly different in fish. Furthermore, in gills, glutathione content had significantly increased while SOD activity had significantly decreased in contaminated fish compared to controls. On the other hand, CAT and GPx activities were not affected. Chronic exposure to PAHs disturbing the first step (SOD) and inhibiting the second step (GPx and CAT) could induce oxidative stress in tissues by the formation of oxygen radicals. After the postexposure period, there was no significant difference between control and contaminated fish in any of the antioxidant defense parameters measured in gills, attesting to the reversibility of the effects.

  16. Brachycorynella asparagi (Mordv.) Induced—Oxidative Stress and Antioxidative Defenses of Asparagus officinalis L.

    PubMed Central

    Borowiak-Sobkowiak, Beata; Woźniak, Agnieszka; Bednarski, Waldemar; Formela, Magda; Samardakiewicz, Sławomir; Morkunas, Iwona

    2016-01-01

    The aim of this study was to investigate whether and to what extent oxidative stress is induced in leaves of one- and two-month-old plants of Asparagus officinalis L. cv. Argenteuil infested by Brachycorynella asparagi (Mordvilko) at a varied population size. The pest B. asparagi has been described as the most damaging species feeding on asparagus. Analyses using electron paramagnetic resonance (EPR) demonstrated generally higher concentrations of semiquinone radicals with g-values of 2.0045 ± 0.0005 and 2.0026 ± 0.0005 in Asparagus officinalis (A. officinalis) leaves after Brachycorynella asparagi (B. asparagi) infestation than in the control. Observations of leaves under a confocal microscope showed a post-infestation enhanced generation of the superoxide anion radical (O2•−) and hydrogen peroxide (H2O2) in comparison to the control. Strong fluctuations in Mn2+ ion levels detected by EPR spectroscopy versus time were detected in leaves infested by aphids, which may indicate the involvement of these ions in the control of O2•− production. An enhanced superoxide dismutase activity is an important element in leaf defense against oxidative stress. Visible symptoms were found in aphid-infested A. officinalis. Damage to leaves of one- and two-month-old A. officinalis plants by the aphid B. asparagi was dependent on the intensity, duration of infestation and plant age. PMID:27775613

  17. Brachycorynella asparagi (Mordv.) Induced-Oxidative Stress and Antioxidative Defenses of Asparagus officinalis L.

    PubMed

    Borowiak-Sobkowiak, Beata; Woźniak, Agnieszka; Bednarski, Waldemar; Formela, Magda; Samardakiewicz, Sławomir; Morkunas, Iwona

    2016-10-20

    The aim of this study was to investigate whether and to what extent oxidative stress is induced in leaves of one- and two-month-old plants of Asparagus officinalis L. cv. Argenteuil infested by Brachycorynella asparagi (Mordvilko) at a varied population size. The pest B. asparagi has been described as the most damaging species feeding on asparagus. Analyses using electron paramagnetic resonance (EPR) demonstrated generally higher concentrations of semiquinone radicals with g-values of 2.0045 ± 0.0005 and 2.0026 ± 0.0005 in Asparagus officinalis (A. officinalis) leaves after Brachycorynella asparagi (B. asparagi) infestation than in the control. Observations of leaves under a confocal microscope showed a post-infestation enhanced generation of the superoxide anion radical (O₂(•-)) and hydrogen peroxide (H₂O₂) in comparison to the control. Strong fluctuations in Mn(2+) ion levels detected by EPR spectroscopy versus time were detected in leaves infested by aphids, which may indicate the involvement of these ions in the control of O₂(•-) production. An enhanced superoxide dismutase activity is an important element in leaf defense against oxidative stress. Visible symptoms were found in aphid-infested A. officinalis. Damage to leaves of one- and two-month-old A. officinalis plants by the aphid B. asparagi was dependent on the intensity, duration of infestation and plant age.

  18. Shift in aggregation, ROS generation, antioxidative defense, lysozyme and acetylcholinesterase activities in the cells of an Indian freshwater sponge exposed to washing soda (sodium carbonate).

    PubMed

    Mukherjee, Soumalya; Ray, Mitali; Ray, Sajal

    2016-09-01

    Washing soda, chemically identified as anhydrous sodium carbonate, is a popular cleaning agent among the rural and urban populations of India which often contaminates the freshwater ponds and lakes, the natural habitat of sponge Eunapius carteri. Present investigation deals with estimation of cellular aggregation, generation of ROS and activities of antioxidant enzymes, lysozyme and acetylcholinesterase in the cells of E. carteri under the environmentally realistic concentrations of washing soda. Prolonged treatment of washing soda inhibited the degree of cellular aggregation. Experimental exposure of 8 and 16mg/l of sodium carbonate for 48h elevated the physiological level of reactive oxygen species (ROS) generation in the agranulocytes, semigranulocytes and granulocytes of E. carteri, whereas, treatment of 192h inhibited the ROS generation in three cellular morphotypes. Activities of superoxide dismutase, catalase and glutathione-S-transferase were recorded to be inhibited under prolonged exposure of washing soda. Washing soda mediated inhibition of ROS generation and depletion in the activities of antioxidant enzymes were indicative to an undesirable shift in cytotoxic status and antioxidative defense in E. carteri. Inhibition in the activity of lysozyme under the treatment of sodium carbonate was suggestive to a severe impairment of the innate immunological efficiency of E. carteri distributed in the washing soda contaminated habitat. Washing soda mediated inhibition in the activity of acetylcholinesterase indicated its neurotoxicity in E. carteri. Washing soda, a reported environmental contaminant, affected adversely the immunophysiological status of E. carteri with reference to cellular aggregation, oxidative stress, antioxidative defense, lysozyme and acetylcholinesterase activity.

  19. Effect of static magnetic fields and phloretin on antioxidant defense system of human fibroblasts.

    PubMed

    Pawłowska-Góral, Katarzyna; Kimsa-Dudek, Magdalena; Synowiec-Wojtarowicz, Agnieszka; Orchel, Joanna; Glinka, Marek; Gawron, Stanisław

    2016-08-01

    The available evidence from in vitro and in vivo studies is deemed not sufficient to draw conclusions about the potential health effects of static magnetic field (SMF) exposure. Therefore, the aim of the present study was to determine the influence of static magnetic fields and phloretin on the redox homeostasis of human dermal fibroblasts. Control fibroblasts and fibroblasts treated with phloretin were subjected to the influence of static magnetic fields. Three chambers with static magnetic fields of different intensities (0.4, 0.55, and 0.7 T) were used in the study. Quantification of superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2), glutathione peroxidase 1 (GPX1), microsomal glutathione S-transferase 1 (MGST1), glutathione reductase (GSR), and catalase (CAT) messenger RNAs (mRNAs) was performed by means of real-time reverse transcription PCR (QRT-PCR) technique. Superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities were measured using a commercially available kit. No significant differences were found in SOD1, SOD2, GPX1, MGST1, GSR, and CAT mRNA levels among the studied groups in comparison to the control culture without phloretin and without the magnet. There were also no changes in SOD, GPx, and CAT activities. In conclusion, our study indicated that static magnetic fields generated by permanent magnets do not exert a negative influence on the oxidative status of human dermal fibroblasts. Based on these studies, it may also be concluded that phloretin does not increase its antioxidant properties under the influence of static magnetic fields. However, SMF-induced modifications at the cellular and molecular level require further clarification.

  20. Interaction of hypercaloric diet and physical exercise on lipid profile, oxidative stress and antioxidant defenses.

    PubMed

    Burneiko, Regina C M; Diniz, Yeda S; Galhardi, Cristiano M; Rodrigues, Hosana G; Ebaid, Geovana M X; Faine, Luciane A; Padovani, Carlos R; Cicogna, Antonio C; Novelli, Ethel L B

    2006-07-01

    The present study examined the interaction of hypercaloric diet (HD) and physical exercise on lipid profile and oxidative stress in serum and liver of rats. Male Wistar rats (60-days-old) were fed with a control (C) and hypercaloric diet (H). Each of the two dietary groups (C and H) was divided into three subgroups (n=8), sedentary (CS and HS), exercised 2days a week (CE2 and HE2) and exercised 5days a week (CE5 and HE5). The swimming was selected as a model for exercise performance. After 8-weeks exercised rats showed decreased lactate dehydrogenase serum activities, demonstrating the effectiveness of the swimming as an aerobic-training protocol. Exercise 5-days a week reduced the body weight gain. Triacylglycerol (TG) and very low-density lipoprotein (VLDL-C) were increased in HD-fed rats. HE5 and CE5 rats had decreased TG, VLDL-C and cholesterol. HE2 rats had enhanced high-density lipoprotein (HDL-C) in serum. No alterations were observed in lipid hydroperoxide (LH), while total antioxidant substances (TAS) were increased in serum of exercised rats. HD-fed rats had hepatic TG accumulation. Superoxide dismutase activities were increased and catalase was decreased in liver of exercised rats. The interaction of HD and physical exercise reduced TAS and enhanced LH levels in hepatic tissue. In conclusion, this study confirmed the beneficial effect of physical exercise as a dyslipidemic-lowering component. Interaction of HD and physical exercise had discrepant effects on serum and liver oxidative stress. The interaction of HD and physical exercise reduced the oxidative stress in serum. HD and physical exercise interaction had pro-oxidant effect on hepatic tissue, suggesting that more studies should be done before using physical exercise as an adjunct therapy to reduce the adverse effects of HD.

  1. Effect of nonylphenol on male reproduction: Analysis of rat epididymal biochemical markers and antioxidant defense enzymes

    SciTech Connect

    Aly, Hamdy A.A.; Domènech, Òscar; Banjar, Zainy M.

    2012-06-01

    The mechanism by which nonylphenol (NP) interferes with male reproduction is not fully elucidated. Therefore, the present study was conducted to evaluate the effect of NP on male reproductive organ's weight, sperm characteristics, and to elucidate the nature and mechanism of action of NP on the epididymis. Adult male Wistar rats were gavaged with NP, dissolved in corn oil, at 0, 100, 200 or 300 mg/kg/day for 30 consecutive days. Control rats were gavaged with vehicle (corn oil) alone. Body weight did not show any significant change while, absolute testes and epididymides weights were significantly decreased. Sperm count in cauda and caput/corpus epididymides, and sperm motility was significantly decreased. Daily sperm production was significantly decreased in a dose-related manner. Sperm transit time in cauda epididymis was significantly decreased by 300 mg/kg, while in the caput/corpus epididymis it was significantly decreased by 200 and 300 mg/kg of NP. Plasma LDH was significantly increased while; plasma testosterone was significantly decreased in a dose-related pattern. In the epididymal sperm, NP decreased acrosome integrity, Δψm and 5′-nucleotidase activity. Hydrogen peroxide (H{sub 2}O{sub 2}) production and LPO were significantly increased in a dose-related pattern. The activities of SOD, CAT and GPx were significantly decreased in the epididymal sperm. In conclusion, this study revealed that NP treatment impairs spermatogenesis and has a cytotoxic effect on epididymal sperm. It disrupts the prooxidant and antioxidant balance. This leads oxidative stress in epididymal sperms of rat. Moreover, the reduction in sperm transit time may affect sperm quality and fertility potential. -- Highlights: ► The nature and mechanism of action of NP on rat epididymis were elucidated. ► NP decreased sperm count, motility, daily sperm production and sperm transit time. ► NP decreased sperm acrosome integrity, Δψm and 5′-nucleotidase activity. ► Plasma LDH was

  2. Ethanol Extract of Ganoderma lucidum Augments Cellular Anti-oxidant Defense through Activation of Nrf2/HO-1

    PubMed Central

    Lee, Yoo-hwan; Kim, Jung-hee; Song, Choon-ho; Jang, Kyung-jeon; kim, Cheol-hong; Kang, Ji- Sook; Choi, Yung-hyun

    2016-01-01

    cellular anti-oxidant defense capacity through activation of Nrf2/HO-1, thereby protecting C2C12 myoblasts from H2O2-induced oxidative cytotoxicity. PMID:27280051

  3. Effects of molybdenum on water utilization, antioxidative defense system and osmotic-adjustment ability in winter wheat (Triticum aestivum) under drought stress.

    PubMed

    Wu, Songwei; Hu, Chengxiao; Tan, Qiling; Nie, Zhaojun; Sun, Xuecheng

    2014-10-01

    Molybdenum (Mo), as an essential trace element in plants, plays an essential role in abiotic stress tolerance of plants. To obtain a better understanding of drought tolerance enhanced by Mo, a hydroponic trial was conducted to investigate the effects of Mo on water utilization, antioxidant enzymes, non-enzymatic antioxidants, and osmotic-adjustment products in the Mo-efficient '97003' and Mo-inefficient '97014' under PEG simulated drought stress. Our results indicate that Mo application significantly enhanced Pn, chlorophyll, dry matter, grain yield, biomass, RWC and WUE and decreased Tr, Gs and water loss of wheat under drought stress, suggesting that Mo application improved the water utilization capacity in wheat. The activities of antioxidant enzymes such as superoxide dismutase, peroxidase, catalase, ascorbate peroxidase and the contents of non-enzymatic antioxidants content such as ascorbic acid, reduced glutathione, carotenoid were significantly increased and malonaldehyde contents were decreased by Mo application under PEG simulated drought stress, suggesting that Mo application enhanced the ability of scavenging active oxygen species. The osmotic-adjustment products such as soluble protein, proline and soluble sugar were also increased by Mo application under PEG simulated drought stress, indicating that Mo improved the osmotic adjustment ability in wheat. It is hypothesized that Mo application might improve the drought tolerance of wheat by enhancing water utilization capability and the abilities of antioxidative defense and osmotic adjustment. Similarities and differences between the Mo-efficient and Mo-inefficient cultivars wheat in response to Mo under drought stress are discussed.

  4. The impact of cold acclimation and hibernation on antioxidant defenses in the ground squirrel (Spermophilus citellus): an update.

    PubMed

    Vucetic, Milica; Stancic, Ana; Otasevic, Vesna; Jankovic, Aleksandra; Korac, Aleksandra; Markelic, Milica; Velickovic, Ksenija; Golic, Igor; Buzadzic, Biljana; Storey, Kenneth B; Korac, Bato

    2013-12-01

    Any alteration in oxidative metabolism is coupled with a corresponding response by an antioxidant defense (AD) in appropriate subcellular compartments. Seasonal hibernators pass through circannual metabolic adaptations that allow them to either maintain euthermy (cold acclimation) or enter winter torpor with body temperature falling to low values. The present study aimed to investigate the corresponding pattern of AD enzyme protein expressions associated with these strategies in the main tissues involved in whole animal energy homeostasis: brown and white adipose tissues (BAT and WAT, respectively), liver, and skeletal muscle. European ground squirrels (Spermophilus citellus) were exposed to low temperature (4 ± 1 °C) and then divided into two groups: (1) animals fell into torpor (hibernating group) and (2) animals stayed active and euthermic for 1, 3, 7, 12, or 21 days (cold-exposed group). We examined the effects of cold acclimation and hibernation on the tissue-dependent protein expression of four enzymes which catalyze the two-step detoxification of superoxide to water: superoxide dismutase 1 and 2 (SOD 1 and 2), catalase (CAT), and glutathione peroxidase (GSH-Px). The results showed that hibernation induced an increase of AD enzyme protein expressions in BAT and skeletal muscle. However, AD enzyme contents in liver were largely unaffected during torpor. Under these conditions, different WAT depots responded by elevating the amounts of specific enzymes, as follows: SOD 1 in retroperitoneal WAT, GSH-Px in gonadal WAT, and CAT in subcutaneous WAT. Similar perturbations of AD enzymes contents were seen in all tissues during cold acclimation, often in a time-dependent manner. It can be concluded that BAT and muscle AD capacity undergo the most dramatic changes during both cold acclimation and hibernation, while liver is relatively unaffected by either condition. Additionally, this study provides a basis for further metabolic study that will illuminate the causes

  5. Trichoderma-plant root colonization: escaping early plant defense responses and activation of the antioxidant machinery for saline stress tolerance.

    PubMed

    Brotman, Yariv; Landau, Udi; Cuadros-Inostroza, Álvaro; Tohge, Takayuki; Takayuki, Tohge; Fernie, Alisdair R; Chet, Ilan; Viterbo, Ada; Willmitzer, Lothar

    2013-03-01

    Trichoderma spp. are versatile opportunistic plant symbionts which can colonize the apoplast of plant roots. Microarrays analysis of Arabidopsis thaliana roots inoculated with Trichoderma asperelloides T203, coupled with qPCR analysis of 137 stress responsive genes and transcription factors, revealed wide gene transcript reprogramming, proceeded by a transient repression of the plant immune responses supposedly to allow root colonization. Enhancement in the expression of WRKY18 and WRKY40, which stimulate JA-signaling via suppression of JAZ repressors and negatively regulate the expression of the defense genes FMO1, PAD3 and CYP71A13, was detected in Arabidopsis roots upon Trichoderma colonization. Reduced root colonization was observed in the wrky18/wrky40 double mutant line, while partial phenotypic complementation was achieved by over-expressing WRKY40 in the wrky18 wrky40 background. On the other hand increased colonization rate was found in roots of the FMO1 knockout mutant. Trichoderma spp. stimulate plant growth and resistance to a wide range of adverse environmental conditions. Arabidopsis and cucumber (Cucumis sativus L.) plants treated with Trichoderma prior to salt stress imposition show significantly improved seed germination. In addition, Trichoderma treatment affects the expression of several genes related to osmo-protection and general oxidative stress in roots of both plants. The MDAR gene coding for monodehydroascorbate reductase is significantly up-regulated and, accordingly, the pool of reduced ascorbic acid was found to be increased in Trichoderma treated plants. 1-Aminocyclopropane-1-carboxylate (ACC)-deaminase silenced Trichoderma mutants were less effective in providing tolerance to salt stress, suggesting that Trichoderma, similarly to ACC deaminase producing bacteria, can ameliorate plant growth under conditions of abiotic stress, by lowering ameliorating increases in ethylene levels as well as promoting an elevated antioxidative capacity.

  6. Antioxidant defenses in the rat placenta in late gestation: increased labyrinthine expression of superoxide dismutases, glutathione peroxidase 3, and uncoupling protein 2.

    PubMed

    Jones, Megan L; Mark, Peter J; Lewis, Jessica L; Mori, Trevor A; Keelan, Jeffery A; Waddell, Brendan J

    2010-08-01

    Placental oxidative stress plays a key role in the pathophysiology of placenta-related disorders, most notably preeclampsia (PE) and intrauterine growth restriction (IUGR). Oxidative stress occurs when accumulation of reactive oxygen species (ROS) damages DNA, proteins and lipids, an outcome that is limited by antioxidant enzymes; mitochondrial uncoupling protein 2 (UCP2) may also limit oxidative stress by reducing ROS production. Here we characterized placental antioxidant defenses during normal gestation and following glucocorticoid-induced IUGR. Placentas were collected on Days 16 and 22 of normal rat pregnancy (term = Day 23) and at Day 22 after dexamethasone treatment from Day 13. Expression of several genes encoding antioxidant enzymes (Sod1, Sod2, Sod3, Cat, Gpx3, Txn1, Txnrd1, Txnrd2, and Txnrd3) and Ucp2 was measured by quantitative RT-PCR in the labyrinth (LZ) and junctional zones (JZ) of the placenta. Expression of Sod1 and Ucp2 mRNAs and the activity of xanthine oxidase, a source of ROS, all increased from Days 16 to 22 in both placental zones, whereas Sod2 and Gpx3 increased only in the rapidly growing LZ. In contrast, Sod3 and Txnrd1 expression fell in the LZ over this period, whereas total superoxide dismutase activity remained stable. Dexamethasone treatment reduced fetal-placental growth and LZ expression of Ucp2 but increased JZ expression of Txn1. Indices of placental oxidative damage (TBARS, F(2)-isoprostanes, and 8-OHdG) did not change with gestational age or dexamethasone, indicative of adequate antioxidant protection. Overall, our data suggest that the rat placenta is protected from oxidative stress by the dynamic zone- and stage-dependent expression of antioxidant defense genes.

  7. Hydrogen-Rich Water Intake Accelerates Oral Palatal Wound Healing via Activation of the Nrf2/Antioxidant Defense Pathways in a Rat Model

    PubMed Central

    Orihuela-Campos, Rita Cristina; Fukui, Makoto; Ito, Hiro-O

    2016-01-01

    The wound healing process attempts to restore the integrity and function of the injured tissue. Additionally, proinflammatory cytokines, growth factors, and oxidative stress play important roles in wound healing. The aim of this study was to determine whether hydrogen-rich water intake induces the activation of the Nrf2/antioxidant defense pathway in rat palatal tissue, thereby reducing systemic oxidative stress and proinflammatory cytokine levels and promoting healing-associated genes. A circular excisional wound was created in the oral palatal region, and the wound healing process was observed. The rats were divided into two experimental groups in which either hydrogen-rich water or distilled water was consumed. In the drinking hydrogen-rich water, the palatal wound healing process was accelerated compared to that in the control group. As molecular hydrogen upregulated the Nrf2 pathway, systemic oxidative stresses were decreased by the activation of antioxidant activity. Furthermore, hydrogen-rich water intake reduced proinflammatory cytokine levels and promoted the expression of healing-associated factors in rat palatal tissue. In conclusion, hydrogen-rich water intake exhibited multiple beneficial effects through activation of the Nrf2/antioxidant defense pathway. The results of this study support the hypothesis that oral administration of hydrogen-rich water benefits the wound healing process by decreasing oxidative stress and inflammatory responses. PMID:26798423

  8. Hydrogen-Rich Water Intake Accelerates Oral Palatal Wound Healing via Activation of the Nrf2/Antioxidant Defense Pathways in a Rat Model.

    PubMed

    Tamaki, Naofumi; Orihuela-Campos, Rita Cristina; Fukui, Makoto; Ito, Hiro-O

    2016-01-01

    The wound healing process attempts to restore the integrity and function of the injured tissue. Additionally, proinflammatory cytokines, growth factors, and oxidative stress play important roles in wound healing. The aim of this study was to determine whether hydrogen-rich water intake induces the activation of the Nrf2/antioxidant defense pathway in rat palatal tissue, thereby reducing systemic oxidative stress and proinflammatory cytokine levels and promoting healing-associated genes. A circular excisional wound was created in the oral palatal region, and the wound healing process was observed. The rats were divided into two experimental groups in which either hydrogen-rich water or distilled water was consumed. In the drinking hydrogen-rich water, the palatal wound healing process was accelerated compared to that in the control group. As molecular hydrogen upregulated the Nrf2 pathway, systemic oxidative stresses were decreased by the activation of antioxidant activity. Furthermore, hydrogen-rich water intake reduced proinflammatory cytokine levels and promoted the expression of healing-associated factors in rat palatal tissue. In conclusion, hydrogen-rich water intake exhibited multiple beneficial effects through activation of the Nrf2/antioxidant defense pathway. The results of this study support the hypothesis that oral administration of hydrogen-rich water benefits the wound healing process by decreasing oxidative stress and inflammatory responses.

  9. Response of the antioxidant defense system to tert-butyl hydroperoxide and hydrogen peroxide in a human hepatoma cell line (HepG2).

    PubMed

    Alía, Mario; Ramos, Sonia; Mateos, Raquel; Bravo, Laura; Goya, Luis

    2005-01-01

    The aim of this work was to investigate the response of the antioxidant defense system to two oxidative stressors, hydrogen peroxide and tert-butyl hydroperoxide, in HepG2 cells in culture. The parameters evaluated included enzyme activity and gene expression of superoxide dismutase, catalase, glutathione peroxidase, and activity of glutathione reductase. Besides, markers of the cell damage and oxidative stress evoked by the stressors such as cell viability, intracellular reactive oxygen species generation, malondialdehyde levels, and reduced glutathione concentration were evaluated. Both stressors, hydrogen peroxide and tert-butyl hydroperoxide, enhanced cell damage and reactive oxygen species generation at doses above 50 microM. The concentration of reduced glutathione decreased, and levels of malondialdehyde and activity of the antioxidant enzymes consistently increased only when HepG2 cells were treated with tert-butyl hydroperoxide but not when hydrogen peroxide was used. A slight increase in the gene expression of Cu/Zn superoxide dismutase and catalase with 500 microM tert-butyl hydroperoxide and of catalase with 200 microM hydrogen peroxide was observed. The response of the components of the antioxidant defense system evaluated in this study indicates that tert-butyl hydroperoxide evokes a consistent cellular stress in HepG2.

  10. Calcium Mitigates Arsenic Toxicity in Rice Seedlings by Reducing Arsenic Uptake and Modulating the Antioxidant Defense and Glyoxalase Systems and Stress Markers.

    PubMed

    Rahman, Anisur; Mostofa, Mohammad Golam; Alam, Md Mahabub; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    2015-01-01

    The effect of exogenous calcium (Ca) on hydroponically grown rice seedlings was studied under arsenic (As) stress by investigating the antioxidant and glyoxalase systems. Fourteen-day-old rice (Oryza sativa L. cv. BRRI dhan29) seedlings were exposed to 0.5 and 1 mM Na2HAsO4 alone and in combination with 10 mM CaCl2 (Ca) for 5 days. Both levels of As caused growth inhibition, chlorosis, reduced leaf RWC, and increased As accumulation in the rice seedlings. Both doses of As in growth medium induced oxidative stress through overproduction of reactive oxygen species (ROS) by disrupting the antioxidant defense and glyoxalase systems. Exogenous application of Ca along with both levels of As significantly decreased As accumulation and restored plant growth and water loss. Calcium supplementation in the As-exposed rice seedlings reduced ROS production, increased ascorbate (AsA) content, and increased the activities of monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT), glutathione peroxidase (GPX), superoxide dismutase (SOD), and the glyoxalase I (Gly I) and glyoxalase II (Gly II) enzymes compared with seedlings exposed to As only. These results suggest that Ca supplementation improves rice seedlings tolerance to As-induced oxidative stress by reducing As uptake, enhancing their antioxidant defense and glyoxalase systems, and also improving growth and physiological condition.

  11. Calcium Mitigates Arsenic Toxicity in Rice Seedlings by Reducing Arsenic Uptake and Modulating the Antioxidant Defense and Glyoxalase Systems and Stress Markers

    PubMed Central

    Rahman, Anisur; Mostofa, Mohammad Golam; Alam, Md. Mahabub; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    2015-01-01

    The effect of exogenous calcium (Ca) on hydroponically grown rice seedlings was studied under arsenic (As) stress by investigating the antioxidant and glyoxalase systems. Fourteen-day-old rice (Oryza sativa L. cv. BRRI dhan29) seedlings were exposed to 0.5 and 1 mM Na2HAsO4 alone and in combination with 10 mM CaCl2 (Ca) for 5 days. Both levels of As caused growth inhibition, chlorosis, reduced leaf RWC, and increased As accumulation in the rice seedlings. Both doses of As in growth medium induced oxidative stress through overproduction of reactive oxygen species (ROS) by disrupting the antioxidant defense and glyoxalase systems. Exogenous application of Ca along with both levels of As significantly decreased As accumulation and restored plant growth and water loss. Calcium supplementation in the As-exposed rice seedlings reduced ROS production, increased ascorbate (AsA) content, and increased the activities of monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT), glutathione peroxidase (GPX), superoxide dismutase (SOD), and the glyoxalase I (Gly I) and glyoxalase II (Gly II) enzymes compared with seedlings exposed to As only. These results suggest that Ca supplementation improves rice seedlings tolerance to As-induced oxidative stress by reducing As uptake, enhancing their antioxidant defense and glyoxalase systems, and also improving growth and physiological condition. PMID:26798635

  12. Co-occurring increases of calcium and organellar reactive oxygen species determine differential activation of antioxidant and defense enzymes in Ulva compressa (Chlorophyta) exposed to copper excess.

    PubMed

    Gonzalez, Alberto; Vera, Jeannette; Castro, Jorge; Dennett, Geraldine; Mellado, Macarena; Morales, Bernardo; Correa, Juan A; Moenne, Alejandra

    2010-10-01

    In order to analyse copper-induced calcium release and (reactive oxygen species) ROS accumulation and their role in antioxidant and defense enzymes activation, the marine alga Ulva compressa was exposed to 10 µM copper for 7 d. The level of calcium, extracellular hydrogen peroxide (eHP), intracellular hydrogen peroxide (iHP) and superoxide anions (SA) as well as the activities of ascorbate peroxidase (AP), glutathione reductase (GR), glutathione-S-transferase (GST), phenylalanine ammonia lyase (PAL) and lipoxygenase (LOX) were determined. Calcium release showed a triphasic pattern with peaks at 2, 3 and 12 h. The second peak was coincident with increases in eHP and iHP and the third peak with the second increase of iHP. A delayed wave of SA occurred after day 3 and was not accompanied by calcium release. The accumulation of iHP and SA was mainly inhibited by organellar electron transport chains inhibitors (OETCI), whereas calcium release was inhibited by ryanodine. AP activation ceased almost completely after the use of OETCI. On the other hand, GR and GST activities were partially inhibited, whereas defense enzymes were not inhibited. In contrast, PAL and LOX were inhibited by ryanodine, whereas AP was not inhibited. Thus, copper stress induces calcium release and organellar ROS accumulation that determine the differential activation of antioxidant and defense enzymes.

  13. ABA induces H2O2 production in guard cells, but does not close the stomata on Vicia faba leaves developed at high air humidity.

    PubMed

    Arve, Louise E; Carvalho, Dália R A; Olsen, Jorunn E; Torre, Sissel

    2014-01-01

    Plants developed under constant high (> 85%) relative air humidity (RH) have larger stomata that are unable to close completely. One of the hypotheses for the less responsive stomata is that the plants have reduced sensitivity to abscisic acid (ABA). Both ABA and darkness are signals for stomatal closure and induce the production of the secondary messenger hydrogen peroxide (H2O2). In this study, the ability of Vicia faba plants developed in moderate or high RH to close the stomata in response to darkness, ABA and H2O2 was investigated. Moreover, the ability of the plants to produce H2O2 when treated with ABA or transferred to darkness was also assessed. Our results show that the ABA concentration in moderate RH is not increased during darkness even though the stomata are closing. This indicates that stomatal closure in V. faba during darkness is independent of ABA production. ABA induced both H2O2 production and stomatal closure in stomata formed at moderate RH. H2O2 production, as a result of treatment with ABA, was also observed in stomata formed at high RH, though the closing response was considerably smaller as compared with moderate RH. In either RH, leaf ABA concentration was not affected by darkness. Similarly to ABA treatment, darkness elicited both H2O2 production and stomatal closure following plant cultivation at moderate RH. Contrary to this, neither H2O2 production nor stomatal closure took place when stomata were formed at high RH. These results suggest that the reduced stomatal response in plants developed in continuous high RH is caused by one or more factors downstream of H2O2 in the signaling pathway toward stomatal closure.

  14. Influence of the PDE5 inhibitor tadalafil on redox status and antioxidant defense system in C2C12 skeletal muscle cells.

    PubMed

    Duranti, Guglielmo; Ceci, Roberta; Sgrò, Paolo; Sabatini, Stefania; Di Luigi, Luigi

    2017-03-11

    Phosphodiesterase type 5 inhibitors (PDE5Is), widely known for their beneficial effects onto male erectile dysfunction, seem to exert favorable effects onto metabolism as well. Tadalafil exposure increases oxidative metabolism of C2C12 skeletal muscle cells. A rise in fatty acid (FA) metabolism, requiring more oxygen, could induce a larger reactive oxygen species (ROS) release as a byproduct thus leading to a redox imbalance. The aim of this study was to determine how PDE5I tadalafil influences redox status in skeletal muscle cells to match the increasing oxidative metabolism. To this purpose, differentiated C2C12 skeletal muscle cells were treated with tadalafil and analyzed for total antioxidant capacity (TAC) and glutathione levels as marker of redox status; enzyme activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) engaged in antioxidant defense; and lipid peroxidation (TBARS) and protein carbonyls (PrCar) as markers of oxidative damage. Tadalafil increased total intracellular glutathione (tGSH), CAT, SOD, and GPx enzymatic activities while no changes were found in TAC. A perturbation of redox status, as showed by the decrease in the ratio between reduced/oxidized glutathione (GSH/GSSG), was observed. Nevertheless, it did not cause any change in TBARS and PrCar levels probably due to the enhancement in the antioxidant enzymatic network. Taken together, these data indicate that tadalafil, besides improving oxidative metabolism, may be beneficial to skeletal muscle cells by enhancing the enzymatic antioxidant system capacity.

  15. Isoprenoids and phenylpropanoids are part of the antioxidant defense orchestrated daily by drought-stressed Platanus × acerifolia plants during Mediterranean summers.

    PubMed

    Tattini, Massimiliano; Loreto, Francesco; Fini, Alessio; Guidi, Lucia; Brunetti, Cecilia; Velikova, Violeta; Gori, Antonella; Ferrini, Francesco

    2015-08-01

    The hypothesis was tested that isoprenoids and phenylpropanoids play a prominent role in countering photooxidative stress, following the depletion of antioxidant enzyme activity in plants exposed to severe drought stress under high solar irradiance and high temperatures. Platanus × acerifolia, a high isoprene-emitting species, was drought-stressed during summer (WS) and compared with unstressed controls (WW). Water relations and photosynthetic parameters were measured under mild, moderate, and severe drought stress conditions. Volatile and nonvolatile isoprenoids, antioxidant enzymes, and phenylpropanoids were measured with the same time course, but in four different periods of the day. Drought severely inhibited photosynthesis, whereas it did not markedly affect the photochemical machinery. Isoprene emission and zeaxanthin concentration were higher in WS than in WW leaves, particularly at mild and moderate stresses, and during the hottest hours of the day. The activities of catalase and ascorbate peroxidase steeply declined during the day, while the activity of guaiacol peroxidase and the concentration of quercetin increased during the day, peaking in the hottest hours in both WW and WS plants. Our experiment reveals a sequence of antioxidants that were used daily by plants to orchestrate defense against oxidative stress induced by drought and associated high light and high temperature. Secondary metabolites seem valuable complements of antioxidant enzymes to counter oxidative stress during the hottest daily hours.

  16. Chard (Beta vulgaris L. var. cicla) extract ameliorates hyperglycemia by increasing GLUT2 through Akt2 and antioxidant defense in the liver of rats.

    PubMed

    Gezginci-Oktayoglu, Selda; Sacan, Ozlem; Bolkent, Sehnaz; Ipci, Yesim; Kabasakal, Levent; Sener, Goksel; Yanardag, Refiye

    2014-01-01

    Chard is a plant used as an alternative hypoglycemic agent by diabetic people in Turkey. The aim of this study was to examine the molecular mechanism of hypoglycemic effects of chard extract. Male Sprague-Dawley rats (6-7 months old) were divided into five groups for this investigation: (1) control, (2) hyperglycemic, (3) hyperglycemic+chard, (4) hyperglycemic+insulin, (5) hyperglycemic+chard+insulin. Fourteen days after animals were rendered hyperglycemic by intraperitoneal injection of 60 mg/kg streptozotocin, the chard water extract (2 g/kg/day) or/and insulin (6 U/kg/day) was administered for 45 days. Hypoglycemic effect of chard extract was demonstrated by a significant reduction in the fasting blood glucose and increased glycogen levels in liver of chard extract-treated hyperglycemic rats. Moreover, activity of adenosine deaminase, which is suggested as an important enzyme for modulating the bioactivity of insulin, was decreased by chard treatment. Immunostaining analysis showed increased nuclear translocation of Akt2 and synthesis of GLUT2 in the hepatocytes of chard or/and insulin-treated hyperglycemic rats. The oxidative stress was decreased and antioxidant defense was increased by chard extract or/and insulin treatment to hyperglycemic rats according to the decreased malondialdehyde formation, the activities of catalase, superoxide dismutase, myeloperoxidase and increased glutathione levels. These findings suggest that chard extract might improve glucose response by increasing GLUT2 through Akt2 and antioxidant defense in the liver.

  17. Effects of the Cellcultured Acanthopanax senticosus Extract on Antioxidative Defense System and Membrane Fluidity in the Liver of Type 2 Diabetes Mouse

    PubMed Central

    Hong, Jung-Hee; Cha, Youn-Soo; Rhee, Soon-Jae

    2009-01-01

    This study examined the effect of cellcultured Acanthopanax senticosus (A. senticosus) extract on the antioxidative defense system, oxidative stress and cell membrane fluidity in the liver of type 2 diabetes in the C57BL/6J mouse as an animal which is genetically prone to develop insulin resistance and obesity/diabetes. C57BL/6J mice were randomly divided, control diet (N-C), high fat diet (DM-C), control diet plus A. senticosus extract (N-CASM), and high fat diet plus A. senticosus extract (DM-CASM). The mice were orally administered an A. senticosus extract (0.5 g/kg body weight) in the N-CASM and DM-CASM groups once a day for 12 weeks, and distilled water in the N-C and DM-C groups. Cellcultured A. senticosus extract was found to be excellent for strengthening the antioxidative defense system, reducing the generation of reactive oxygen species (ROS) and damaging oxidative substances, and maintaing membrane fluidity (MF) in the liver of type 2 diabetes mouse. PMID:19590714

  18. Skeletal muscle uncoupling-induced longevity in mice is linked to increased substrate metabolism and induction of the endogenous antioxidant defense system.

    PubMed

    Keipert, S; Ost, M; Chadt, A; Voigt, A; Ayala, V; Portero-Otin, M; Pamplona, R; Al-Hasani, H; Klaus, S

    2013-03-01

    Ectopic expression of uncoupling protein 1 (UCP1) in skeletal muscle (SM) mitochondria increases lifespan considerably in high-fat diet-fed UCP1 Tg mice compared with wild types (WT). To clarify the underlying mechanisms, we investigated substrate metabolism as well as oxidative stress damage and antioxidant defense in SM of low-fat- and high-fat-fed mice. Tg mice showed an increased protein expression of phosphorylated AMP-activated protein kinase, markers of lipid turnover (p-ACC, FAT/CD36), and an increased SM ex vivo fatty acid oxidation. Surprisingly, UCP1 Tg mice showed elevated lipid peroxidative protein modifications with no changes in glycoxidation or direct protein oxidation. This was paralleled by an induction of catalase and superoxide dismutase activity, an increased redox signaling (MAPK signaling pathway), and increased expression of stress-protective heat shock protein 25. We conclude that increased skeletal muscle mitochondrial uncoupling in vivo does not reduce the oxidative stress status in the muscle cell. Moreover, it increases lipid metabolism and reactive lipid-derived carbonyls. This stress induction in turn increases the endogenous antioxidant defense system and redox signaling. Altogether, our data argue for an adaptive role of reactive species as essential signaling molecules for health and longevity.

  19. Ornithine and Homocitrulline Impair Mitochondrial Function, Decrease Antioxidant Defenses and Induce Cell Death in Menadione-Stressed Rat Cortical Astrocytes: Potential Mechanisms of Neurological Dysfunction in HHH Syndrome.

    PubMed

    Zanatta, Ângela; Rodrigues, Marília Danyelle Nunes; Amaral, Alexandre Umpierrez; Souza, Débora Guerini; Quincozes-Santos, André; Wajner, Moacir

    2016-09-01

    Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is caused by deficiency of ornithine translocase leading to predominant tissue accumulation and high urinary excretion of ornithine (Orn), homocitrulline (Hcit) and ammonia. Although affected patients commonly present neurological dysfunction manifested by cognitive deficit, spastic paraplegia, pyramidal and extrapyramidal signs, stroke-like episodes, hypotonia and ataxia, its pathogenesis is still poorly known. Although astrocytes are necessary for neuronal protection. Therefore, in the present study we investigated the effects of Orn and Hcit on cell viability (propidium iodide incorporation), mitochondrial function (thiazolyl blue tetrazolium bromide-MTT-reduction and mitochondrial membrane potential-ΔΨm), antioxidant defenses (GSH) and pro-inflammatory response (NFkB, IL-1β, IL-6 and TNF-α) in unstimulated and menadione-stressed cortical astrocytes that were previously shown to be susceptible to damage by neurotoxins. We first observed that Orn decreased MTT reduction, whereas both amino acids decreased GSH levels, without altering cell viability and the pro-inflammatory factors in unstimulated astrocytes. Furthermore, Orn and Hcit decreased cell viability and ΔΨm in menadione-treated astrocytes. The present data indicate that the major compounds accumulating in HHH syndrome impair mitochondrial function and reduce cell viability and the antioxidant defenses in cultured astrocytes especially when stressed by menadione. It is presumed that these mechanisms may be involved in the neuropathology of this disease.

  20. Influence of TiO2 nanoparticles on cellular antioxidant defense and its involvement in genotoxicity in HepG2 cells

    NASA Astrophysics Data System (ADS)

    Petković, Jana; Žegura, Bojana; Filipič, Metka

    2011-07-01

    We investigated the effects of two types of TiO2 nanoparticles (<25 nm anatase, TiO2-An; <100 nm rutile, TiO2-Ru) on cellular antioxidant defense in HepG2 cells. We previously showed that in HepG2 cells, TiO2 nanoparticles are not toxic, although they induce oxidative DNA damage, production of intracellular reactive oxygen species, and up-regulation of mRNA expression of DNA-damage-responsive genes (p53, p21, gadd45α and mdm2). In the present study, we measured changes in mRNA expression of several antioxidant enzymes: catalase, superoxide dismutase, glutathione peroxidase, nitric oxide synthase, glutathione reductase and glutamate-cysteine ligase. As reduced glutathione has a central role in cellular antioxidant defense, we determined the effects of TiO2 nanoparticles on changes in the intracellular glutathione content. To confirm a role for glutathione in protection against TiO2-nanoparticle-induced DNA damage, we compared the extent of TiO2-nanoparticle-induced DNA damage in HepG2 cells that were glutathione depleted with buthionine-(S,R)-sulfoximine pretreatment and in nonglutathione-depleted cells. Our data show that both types of TiO2 nanoparticles up-regulate mRNA expression of oxidative-stress-related genes, with TiO2-Ru being a stronger inducer than TiO2-An. Both types of TiO2 nanoparticles also induce dose-dependent increases in intracellular glutathione levels, and in glutathione-depleted cells, TiO2-nanoparticle-induced DNA damage was significantly greater than in nonglutathione-depleted cells. Interestingly, the glutathione content and the extent of DNA damage were significantly higher in TiO2-An- than TiO2-Ru-exposed cells. Thus, we show that TiO2 nanoparticles cause activation of cellular antioxidant processes, and that intracellular glutathione has a critical role in defense against this TiO2-nanoparticle-induced DNA damage.

  1. A novel class of bifunctional acylpeptide hydrolases--potential role in the antioxidant defense systems of the Antarctic fish Trematomus bernacchii.

    PubMed

    Gogliettino, Marta; Riccio, Alessia; Balestrieri, Marco; Cocca, Ennio; Facchiano, Angelo; D'Arco, Teresa M; Tesoro, Clara; Rossi, Mosè; Palmieri, Gianna

    2014-01-01

    Oxidative challenge is an important factor affecting the adaptive strategies of Antarctic fish, but data on antioxidant defenses in these organisms remain scarce. In this context, a key role could be played by acylpeptide hydrolase (APEH), which was recently hypothesized to participate in the degradation of oxidized and cytotoxic proteins, although its physiological function is still not fully clarified. This study represents the first report on piscine members of this enzyme family, specifically from the Antarctic teleost Trematomus bernacchii. The cDNAs corresponding to two apeh genes were isolated, and the respective proteins were functionally and structurally characterized with the aim of understanding the biological significance of these proteases in Antarctic fish. Both APEH isoforms (APEH-1Tb and APEH-2Tb ) showed distinct temperature-kinetic behavior, with significant differences in the Km values. Moreover, beside the typical acylpeptide hydrolase activity, APEH-2Tb showed remarkable oxidized protein endohydrolase activity towards oxidized BSA, suggesting that this isoform could play a homeostatic role in removing oxidatively damaged proteins, sustaining the antioxidant defense systems. The 3D structures of both APEHs were predicted, and a possible relationship was found between the substrate specificity/affinity and the marked changes in the number of charged residues and hydrophobicity properties surrounding their catalytic sites. Our results demonstrated the occurrence of two APEH isoforms in T. bernacchii, belonging to different phylogenetic clusters, identified for the first time, and showing distinct molecular and temperature-kinetic behaviors. In addition, we suggest that the members of the new cluster 'APEH-2' could participate in reactive oxygen species detoxification as phase 3 antioxidant enzymes, enhancing the protein degradation machinery.

  2. Polyamine regulates tolerance to water stress in leaves of white clover associated with antioxidant defense and dehydrin genes via involvement in calcium messenger system and hydrogen peroxide signaling

    PubMed Central

    Li, Zhou; Zhang, Yan; Peng, Dandan; Wang, Xiaojuan; Peng, Yan; He, Xiaoshuang; Zhang, Xinquan; Ma, Xiao; Huang, Linkai; Yan, Yanhong

    2015-01-01

    Endogenous polyamine (PA) may play a critical role in tolerance to water stress in plants acting as a signaling molecule activator. Water stress caused increases in endogenous PA content in leaves, including putrescine (Put), spermidine (Spd), and spermine (Spm). Exogenous application of Spd could induce the instantaneous H2O2 burst and accumulation of cytosolic free Ca2+, and activate NADPH oxidase and CDPK gene expression in cells. To a great extent, PA biosynthetic inhibitor reduced the water stress-induced H2O2 accumulation, free cytosolic Ca2+ release, antioxidant enzyme activities and genes expression leading to aggravate water stress-induced oxidative damage, while these suppressing effects were alleviated by the addition of exogenous Spd, indicating PA was involved in water stress-induced H2O2 and cytosolic free Ca2+ production as well as stress tolerance. Dehydrin genes (Y2SK, Y2K, and SK2) were showed to be highly responsive to exogenous Spd. PA-induced antioxidant defense and dehydrin genes expression could be blocked by the scavenger of H2O2 and the inhibitors of H2O2 generation or Ca2+ channels blockers, a calmodulin antagonist, as well as the inhibitor of CDPK. These findings suggested that PA regulated tolerance to water stress in white clover associated with antioxidant defenses and dehydrins via involvement in the calcium messenger system and H2O2 signaling pathways. PA-induced H2O2 production required Ca2+ release, while PA-induced Ca2+ release was also essential for H2O2 production, suggesting an interaction between PA-induced H2O2 and Ca2+ signaling. PMID:26528187

  3. The 5’-AMP-Activated Protein Kinase (AMPK) Is Involved in the Augmentation of Antioxidant Defenses in Cryopreserved Chicken Sperm

    PubMed Central

    Nguyen, Thi Mong Diep; Seigneurin, François; Froment, Pascal; Combarnous, Yves; Blesbois, Elisabeth

    2015-01-01

    Semen cryopreservation is a unique tool for the management of animal genetic diversity. However, the freeze-thaw process causes biochemical and physical alterations which make difficult the restoration of sperm energy-dependent functions needed for fertilization. 5’-AMP activated protein kinase (AMPK) is a key sensor and regulator of intracellular energy metabolism. Mitochondria functions are known to be severely affected during sperm cryopreservation with deleterious oxidative and peroxidative effects leading to cell integrity and functions damages. The aim of this study was thus to examine the role of AMPK on the peroxidation/antioxidant enzymes defense system in frozen-thawed sperm and its consequences on sperm functions. Chicken semen was diluted in media supplemented with or without AMPK activators (AICAR or Metformin [MET]) or inhibitor (Compound C [CC]) and then cryopreserved. AMPKα phosphorylation, antioxidant enzymes activities, mitochondrial potential, ATP, citrate, viability, acrosome reaction ability (AR) and various motility parameters were negatively affected by the freeze-thaw process while reactive oxygen species (ROS) production, lipid peroxidation (LPO) and lactate concentration were dramatically increased. AICAR partially restored superoxide dismutase (SOD), Glutathione Peroxidase (GPx) and Glutathione Reductase (GR), increased ATP, citrate, and lactate concentration and subsequently decreased the ROS and LPO (malondialdehyde) in frozen-thawed semen. Motility parameters were increased (i.e., + 23% for motility, + 34% for rapid sperm) as well as AR (+ 100%). MET had similar effects as AICAR except that catalase activity was restored and that ATP and mitochondrial potential were further decreased. CC showed effects opposite to AICAR on SOD, ROS, LPO and AR and motility parameters. Taken together, our results strongly suggest that, upon freeze-thaw process, AMPK stimulated intracellular anti-oxidative defense enzymes through ATP regulation, thus

  4. Evaluation of hydroxyapatite-bioglass and hydroxyapatite-ethyl vinyl acetate composite extracts on antioxidant defense mechanism and genotoxicity: an in vitro study.

    PubMed

    Arun, M; Silja, P K; Mohanan, P V

    2011-09-01

    Hydroxyapatite-bioglass (HA BG) and hydroxyapatite-ethyl vinyl acetate (HA EVA) are two composite materials that have been developed for bone substitution. Their activity on antioxidant defense mechanism and genotoxicity has not been investigated before. To further confirm its biocompatibility, the present study was undertaken to investigate the effect of HA BG and HA EVA on mice liver antioxidant mechanism along with chromosomal aberrations in human lymphocytes. Physiological saline extract of HA BG and HA EVA showed no adverse effect on liver antioxidant mechanism compared to the cyclophosphamide (CP)-induced toxicity on mice liver homogenate. The results were judged from the in vitro studies made on reduced glutathione, glutathione reductase and lipid peroxidation. These results were well supported by CP- and mytomycin C (MC)-induced genotoxicity studies on human lymphocytes in the presence and absence of a metabolic activator (S9). Hence, it was suggested that these tests could be considered for preliminary toxicological screening of materials intended for clinical applications ahead of in vivo animal model evaluation.

  5. Noise-induced hearing loss (NIHL) as a target of oxidative stress-mediated damage: cochlear and cortical responses after an increase in antioxidant defense.

    PubMed

    Fetoni, Anna Rita; De Bartolo, Paola; Eramo, Sara Letizia Maria; Rolesi, Rolando; Paciello, Fabiola; Bergamini, Christian; Fato, Romana; Paludetti, Gaetano; Petrosini, Laura; Troiani, Diana

    2013-02-27

    This study addresses the relationship between cochlear oxidative damage and auditory cortical injury in a rat model of repeated noise exposure. To test the effect of increased antioxidant defenses, a water-soluble coenzyme Q10 analog (Qter) was used. We analyzed auditory function, cochlear oxidative stress, morphological alterations in auditory cortices and cochlear structures, and levels of coenzymes Q9 and Q10 (CoQ9 and CoQ10, respectively) as indicators of endogenous antioxidant capability. We report three main results. First, hearing loss and damage in hair cells and spiral ganglion was determined by noise-induced oxidative stress. Second, the acoustic trauma altered dendritic morphology and decreased spine number of II-III and V-VI layer pyramidal neurons of auditory cortices. Third, the systemic administration of the water-soluble CoQ10 analog reduced oxidative-induced cochlear damage, hearing loss, and cortical dendritic injury. Furthermore, cochlear levels of CoQ9 and CoQ10 content increased. These findings indicate that antioxidant treatment restores auditory cortical neuronal morphology and hearing function by reducing the noise-induced redox imbalance in the cochlea and the deafferentation effects upstream the acoustic pathway.

  6. Nuclear Heme Oxygenase-1 (HO-1) Modulates Subcellular Distribution and Activation of Nrf2, Impacting Metabolic and Anti-oxidant Defenses*

    PubMed Central

    Biswas, Chhanda; Shah, Nidhi; Muthu, Manasa; La, Ping; Fernando, Amal P.; Sengupta, Shaon; Yang, Guang; Dennery, Phyllis A.

    2014-01-01

    With oxidative injury as well as in some solid tumors and myeloid leukemia cells, heme oxygenase-1 (HO-1), the anti-oxidant, anti-inflammatory, and anti-apoptotic microsomal stress protein, migrates to the nucleus in a truncated and enzymatically inactive form. However, the function of HO-1 in the nucleus is not completely clear. Nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor and master regulator of numerous antioxidants and anti-apoptotic proteins, including HO-1, also accumulates in the nucleus with oxidative injury and in various types of cancer. Here we demonstrate that in oxidative stress, nuclear HO-1 interacts with Nrf2 and stabilizes it from glycogen synthase kinase 3β (GSK3β)-mediated phosphorylation coupled with ubiquitin-proteasomal degradation, thereby prolonging its accumulation in the nucleus. This regulation of Nrf2 post-induction by nuclear HO-1 is important for the preferential transcription of phase II detoxification enzymes such as NQO1 as well as glucose-6-phosphate dehydrogenase (G6PDH), a regulator of the pentose phosphate pathway. Using Nrf2 knock-out cells, we further demonstrate that nuclear HO-1-associated cytoprotection against oxidative stress depends on an HO-1/Nrf2 interaction. Although it is well known that Nrf2 induces HO-1 leading to mitigation of oxidant stress, we propose a novel mechanism by which HO-1, by modulating the activation of Nrf2, sets an adaptive reprogramming that enhances antioxidant defenses. PMID:25107906

  7. Swimming training attenuates oxidative damage and increases enzymatic but not non-enzymatic antioxidant defenses in the rat brain.

    PubMed

    Nonato, L F; Rocha-Vieira, E; Tossige-Gomes, R; Soares, A A; Soares, B A; Freitas, D A; Oliveira, M X; Mendonça, V A; Lacerda, A C; Massensini, A R; Leite, H R

    2016-09-29

    Although it is well known that physical training ameliorates brain oxidative function after injuries by enhancing the levels of neurotrophic factors and oxidative status, there is little evidence addressing the influence of exercise training itself on brain oxidative damage and data is conflicting. This study investigated the effect of well-established swimming training protocol on lipid peroxidation and components of antioxidant system in the rat brain. Male Wistar rats were randomized into trained (5 days/week, 8 weeks, 30 min; n=8) and non-trained (n=7) groups. Forty-eight hours after the last session of exercise, animals were euthanized and the brain was collected for oxidative stress analysis. Swimming training decreased thiobarbituric acid reactive substances (TBARS) levels (P<0.05) and increased the activity of the antioxidant enzyme superoxide dismutase (SOD) (P<0.05) with no effect on brain non-enzymatic total antioxidant capacity, estimated by FRAP (ferric-reducing antioxidant power) assay (P>0.05). Moreover, the swimming training promoted metabolic adaptations, such as increased maximal workload capacity (P<0.05) and maintenance of body weight. In this context, the reduced TBARS content and increased SOD antioxidant activity induced by 8 weeks of swimming training are key factors in promoting brain resistance. In conclusion, swimming training attenuated oxidative damage and increased enzymatic antioxidant but not non-enzymatic status in the rat brain.

  8. Swimming training attenuates oxidative damage and increases enzymatic but not non-enzymatic antioxidant defenses in the rat brain

    PubMed Central

    Nonato, L.F.; Rocha-Vieira, E.; Tossige-Gomes, R.; Soares, A.A.; Soares, B.A.; Freitas, D.A.; Oliveira, M.X.; Mendonça, V.A.; Lacerda, A.C.; Massensini, A.R.; Leite, H.R.

    2016-01-01

    Although it is well known that physical training ameliorates brain oxidative function after injuries by enhancing the levels of neurotrophic factors and oxidative status, there is little evidence addressing the influence of exercise training itself on brain oxidative damage and data is conflicting. This study investigated the effect of well-established swimming training protocol on lipid peroxidation and components of antioxidant system in the rat brain. Male Wistar rats were randomized into trained (5 days/week, 8 weeks, 30 min; n=8) and non-trained (n=7) groups. Forty-eight hours after the last session of exercise, animals were euthanized and the brain was collected for oxidative stress analysis. Swimming training decreased thiobarbituric acid reactive substances (TBARS) levels (P<0.05) and increased the activity of the antioxidant enzyme superoxide dismutase (SOD) (P<0.05) with no effect on brain non-enzymatic total antioxidant capacity, estimated by FRAP (ferric-reducing antioxidant power) assay (P>0.05). Moreover, the swimming training promoted metabolic adaptations, such as increased maximal workload capacity (P<0.05) and maintenance of body weight. In this context, the reduced TBARS content and increased SOD antioxidant activity induced by 8 weeks of swimming training are key factors in promoting brain resistance. In conclusion, swimming training attenuated oxidative damage and increased enzymatic antioxidant but not non-enzymatic status in the rat brain. PMID:27706439

  9. Effects of puffer (Sphoeroides rubripes) supplementation on disruption of antioxidant defense systems in ethanol-treated rats.

    PubMed

    Joo, Jong-Chan; Park, Jae-Hee; Kim, Rae-Young; Jeon, Kyoung-Im; Lee, Hyun-Jung; Seo, Bo-Young; Park, Eunju

    2011-01-01

    We investigated the effects of puffer (Sphoeroides rubripes) supplementation on antioxidant metabolism in ethanol-treated rats. Sprague-Dawley rats were randomly assigned into 4 groups of 7 rats each and fed (1) an AIN-93G diet (NC), (2) 25% ethanol (E), (3) 25% ethanol and an AIN-93G diet containing 1% puffer flesh (E+F), or (4) 25% ethanol and an AIN-93G diet containing 1% puffer skin (E+S) for 5 wk. At the end of the experimental period, the rats were sacrificed and their blood and organs were collected. To evaluate the effect of puffer supplementation, lipid-soluble antioxidant vitamin and conjugated diene (CD) levels, DNA damage, and mRNA expression of heme oxygenase-1 (HO-1) were assessed. Animals that were fed ethanol showed reduced plasma levels of lipid-soluble antioxidant vitamin and significantly increased levels of lipid peroxides, DNA damage, and HO-1 expression. Dietary supplementation with puffer conferred an antioxidant effect by significantly increasing the levels of γ-tocopherol, a lipid-soluble antioxidant vitamin, and by significantly decreasing the plasma levels of CD, DNA damage, and HO-1 expression. These results suggest that consumption of puffer improves the antioxidant status of ethanol-treated rats.

  10. Protective effects of moderate exercise with dietary vitamin C and E on blood antioxidative defense mechanism in rats with streptozotocin-induced diabetes.

    PubMed

    Naziroğlu, Mustafa; Butterworth, Peter J

    2005-04-01

    Daily moderate exercise and supplementation of vitamins C and E (VCE) can be beneficial in diabetes by ameliorating the effects of free radical production. The present study sought to analyze the effect of moderate exercise accompanying VCE supplementation on lipid peroxidation (LP) and antioxidative systems in the blood of streptozotocin-induced diabetic rats. Forty female Wistar rats were randomly divided 4 groups. The 1st and 2nd groups served as the control and diabetic groups, respectively. The 3rd group was the diabetic-exercise group. The 4th group, also diabetic-exercise rats, received VCE-supplemented feed. Animals in the exercised groups were moderately exercised on a treadmill 5 days a week for 3 weeks. Diabetes was induced on Day 0 of the exercise. Plasma and red blood cell (RBC) samples were taken from all animals on Day 20. Glutathione peroxidase, catalase, and reduced glutathione levels in plasma and RBCs, and vitamins A, E, and beta-carotene in plasma were lower in diabetic rats than in control animals, whereas there was a significant increase in platelet counts in both plasma and RBC LP levels. The decreased antioxidant enzymes and vitamins, and the increased LP levels and WBC counts, did improve through exercise only, although their levels were mostly increased by exercise + VCE supplementation. There were no significant changes in the hemoglobin and hematocrit values in the 4 groups. In conclusion, these data demonstrate an increase in LP in the blood of diabetic animals whereas there was a decrease in the antioxidant vitamins and enzymes. However, dietary VCE with moderate exercise may strengthen the antioxidant defense system by decreasing reactive oxygen species.

  11. UV-A Irradiation Activates Nrf2-Regulated Antioxidant Defense and Induces p53/Caspase3-Dependent Apoptosis in Corneal Endothelial Cells

    PubMed Central

    Liu, Cailing; Vojnovic, Dijana; Kochevar, Irene E.; Jurkunas, Ula V.

    2016-01-01

    Purpose To examine whether Nrf2-regulated antioxidant defense and p53 are activated in human corneal endothelial cells (CEnCs) by environmental levels of ultraviolet A (UV-A), a known stimulator of oxidative stress. Methods Immortalized human CEnCs (HCEnCi) were exposed to UV-A fluences of 2.5, 5, 10, or 25 J/cm2, then allowed to recover for 3 to 24 hours. Control HCEnCi did not receive UV-A. Reactive oxygen species (ROS) were measured using H2DCFDA. Cell cytotoxicity was evaluated by lactate dehydrogenase (LDH) release. Levels of Nrf2, HO-1, NQO-1, p53, and caspase3 were detected by immunnoblotting or real-time PCR. Activated caspase3 was measured by immunoblotting and a fluorescence assay. Results Exposure of HCEnCi to 5, 10, and 25 J/cm2 UV-A increased ROS levels compared with controls. Nrf2, HO-1, and NQO-1 mRNA increased 1.7- to 3.2-fold at 3 and 6 hours after irradiation with 2.5 and 5 J/cm2 UV-A. At 6 hours post irradiation, UV-A (5 J/cm2) enhanced nuclear Nrf2 translocation. At 24 hours post treatment, UV-A (5, 10, and 25 J/cm2) produced a 1.8- to 2.8-fold increase in phospho-p53 and a 2.6- to 6.0-fold increase in activated caspase3 compared with controls, resulting in 20% to 42% cell death. Conclusions Lower fluences of UV-A induce Nrf2-regulated antioxidant defense and higher fluences activate p53 and caspase3, indicating that even near-environmental levels of UV-A may affect normal CEnCs. This data suggest that UV-A may especially damage cells deficient in antioxidant defense, and thus may be involved in the etiology of Fuchs' endothelial corneal dystrophy (FECD). PMID:27127932

  12. Effect of Tridax procumbens on liver antioxidant defense system during lipopolysaccharide-induced hepatitis in D-galactosamine sensitised rats.

    PubMed

    Ravikumar, Vilwanathan; Shivashangari, Kanchi Subramanian; Devaki, Thiruvengadam

    2005-01-01

    The present study was carried out to assess the effect of chloroform insoluble fraction of ethanolic extract of Tridax procumbens (TP) against D-Galactosamine/Lipopolysaccharide (D-GalN/LPS)-induced hepatitis in rats. Induction of rats with D-GalN/LPS (300 mg/kg body weight/30 microg/kg body weight) led to a marked increase in lipid peroxidation as measured by thiobarbituric acid reactive substances (TBARS) in liver. Further there was a decline in the activities of enzymic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, glutathione s-transferase and the levels of non-enzymic antioxidants namely reduced glutathione, vitamin C and vitamin E. These biochemical alterations were normalised upon pretreatment with TP extract. Thus, the above results suggest that TP (300 mg/kg body weight orally for 10 days) is very effective in allievating the D-GalN/LPS-induced oxidative stress suggesting its antioxidant property.

  13. [Status of the water-soluble component of the antioxidant defense system in the conditions of 520-day isolation].

    PubMed

    Morukov, B V; Popov, I N; Levin, G; Markin, A A; Zhuravleva, O A; Kuzichkin, D S

    2013-01-01

    In the 520-d chamber experiment within the international project Mars-500 blood samples of 6 male test-subjects of 28 to 39 years of age were analyzed for water-soluble antioxidants: total bilirubin and uric acid; in addition, total antioxidant capacity of blood plasma was determined. Maximal values of these parameters were associated with the most stressful periods of the experiment, i.e. adaptation to the life in isolation and confinement, simulation of the egress onto Martian surface, and change of the diet. On attainment of the homeostatic equilibrium the parameters stabilized on levels slightly lower relative to baseline (pre-isolation) values. Therefore, dynamics of the water-soluble antioxidants reflected adequately the homeostatic reactions to and compensation by organism of the effects of the 520-day life in isolation and confinement.

  14. Using the enzymatic and non-enzymatic antioxidant defense system of the land snail Eobania vermiculata as biomarkers of terrestrial heavy metal pollution.

    PubMed

    El-Shenawy, Nahla S; Mohammadden, Amaal; Al-Fahmie, Zahra Hessenan

    2012-10-01

    The present study aimed to investigate the efficacy of antioxidant defense system of the land snail Eobania vermiculata as biomarkers for terrestrial heavy metal pollution. For this reason, a set of biomarkers was performed on land snails E. vermiculata collected from polluted and non-polluted areas in the field. The biomarkers used were lactate dehydrogenase activity, level of lipid peroxidation, activities of catalase, glutathione peroxidase, glutathione-S-transferase, gamma-glutamyl transferase and content of glutathione, metalothionines, total proteins and total lipid in the digestive gland tissue. The correlation between the bioaccumulation of heavy metal in gland tissue and all the biomarkers in the digestive gland was determined. The results revealed appreciable alterations in the biomarker values in field, accompanied by significant correlations among the biomarkers. Therefore, this study suggests E. vermiculata is a suitable sentinel organism and the selected biomarkers show efficacy for terrestrial heavy metal biomonitoring.

  15. Food-grade argan oil supplementation in molasses enhances fermentative performance and antioxidant defenses of active dry wine yeast.

    PubMed

    Gamero-Sandemetrio, Esther; Torrellas, Max; Rábena, María Teresa; Gómez-Pastor, Rocío; Aranda, Agustín; Matallana, Emilia

    2015-12-01

    The tolerance of the yeast Saccharomyces cerevisiae to desiccation is important for the use of this microorganism in the wine industry, since active dry yeast (ADY) is routinely used as starter for must fermentations. Both biomass propagation and dehydration cause cellular oxidative stress, therefore negatively affecting yeast performance. Protective treatments against oxidative damage, such as natural antioxidants, may have important biotechnological implications. In this study we analysed the antioxidant capacity of pure chemical compounds (quercetin, ascorbic acid, caffeic acid, oleic acid, and glutathione) added to molasses during biomass propagation, and we determine several oxidative damage/response parameters (lipid peroxidation, protein carbonylation, protective metabolites and enzymatic activities) to assess their molecular effects. Supplementation with ascorbic, caffeic or oleic acids diminished the oxidative damage associated to ADY production. Based on these results, we tested supplementation of molasses with argan oil, a natural food-grade ingredient rich in these three antioxidants, and we showed that it improved both biomass yield and fermentative performance of ADY. Therefore, we propose the use of natural, food-grade antioxidant ingredients, such as argan oil, in industrial processes involving high cellular oxidative stress, such as the biotechnological production of the dry starter.

  16. Impact of acute and subchronic asbestos exposure on some parameters of antioxidant defense system and lung tissue injury.

    PubMed

    Kaiglová, A; Kováciková, Z; Hurbánková, M

    1999-07-01

    Asbestos fibers have been used in industry for decades. Deleterious effect of asbestos on the lungs has been documented. However, the mechanism of asbestos related diseases has not been fully explained yet. Numerous papers suggest there is a role of reactive oxygen intermediates (ROI) in asbestos-induced lung disease development. The excess ROI produced can be removed from the lungs by enzymatic and nonenzymatic antioxidants. The aim of our study was to compare the levels of antioxidants (ascorbic acid, retinol, alpha-tocopherol, glutathionperoxidase) as well as some markers of lung injury (lipid peroxides, total amount of protein, alkaline phosphatase) in asbestos treated Wistar-rats both 24 hr and 3 months after exposure to those in the controls, and to find out if the changes in antioxidant levels could affect impairment of the lungs. Decreased levels of antioxidants and increased values of lung tissue injury parameters in exposed groups suggest involvement of ROI in the mechanism of asbestos lung disease development, resulting in lung tissue injury, both 24 hr and 3 months after exposure.

  17. De-submergence responses of antioxidative defense systems in two wetland plants having escape and quiescence strategies.

    PubMed

    Luo, Fang-Li; Thiele, Björn; Janzik, Ingar; Zeng, Bo; Schurr, Ulrich; Matsubara, Shizue

    2012-11-15

    Fast recovery after de-submergence requires efficient protection against oxidative injuries. We investigated whether de-submergence responses of antioxidant systems differ in two wetland plants, Alternanthera philoxeroides and Hemarthria altissima, characterized by 'escape' and 'quiescence' strategies of flood tolerance, respectively. The antioxidant capacity was assessed in the two species during 10d of recovery following 20d of complete submergence (low light+low O(2)) or severe shading (low light+ambient O(2)). The activities of superoxide dismutase and catalase were measured in leaf and root tissues, along with the concentrations of reduced ascorbate, malondialdehyde, and acetaldehyde. In addition, formation of superoxide (O(2)(-)) and hydrogen peroxide (H(2)O(2)) was detected in leaves by chemical staining. Following de-submergence, plants of A. philoxeroides showed a transient burst of acetaldehyde, while the concentration of acetaldehyde increased slowly and stayed high in leaves of H. altissima. In leaves of A. philoxeroides, the variations in O(2)(-) and H(2)O(2) correlated with the levels of light and O(2), respectively, whereas neither of the two reactive oxygen species was detected in H. altissima. For A. philoxeroides, the antioxidant capacities changed mainly in leaves during the recovery. For H. altissima, changes in reduced ascorbate were found in leaves and those of antioxidant enzyme activities in roots. De-submergence caused some lipid peroxidation in leaves of both species. We conclude that de-submergence responses of the detoxification systems differ between A. philoxeroides and H. altissima, especially in leaves. Dynamic changes were found in A. philoxeroides (having the escape strategy), as opposed to little or slow changes in H. altissima (having the quiescence strategy). Whereas the antioxidant capacities are often strongly influenced by light environments, the toxic compounds and lipid peroxidation indicate harmful effects of changing O(2

  18. Effects of copper exposure on the hatching status and antioxidant defense at different developmental stages of embryos and larvae of goldfish Carassius auratus.

    PubMed

    Kong, Xianghui; Jiang, Hongxia; Wang, Shuping; Wu, Xiangmin; Fei, Wei; Li, Li; Nie, Guoxing; Li, Xuejun

    2013-09-01

    This study aims to assess the effects of copper exposure on hatching status and antioxidant defense at different stages of embryos and larvae of goldfish Carassius auratus. In this study, day-old embryos were randomly grouped after fertilization and then exposed to copper concentrations of 0, 0.1, 0.4, 0.7, and 1.0mgL(-1). Copper-exposed fish embryos were sampled every 24h to determine superoxide dismutase (SOD), and catalase (CAT) activities, as well as malondialdehyde (MDA) content. In addition, cumulative mortality and larval deformity were also investigated. The findings showed that cumulative mortality and larval deformity rate increased gradually with copper concentration increase. SOD and CAT activities were inhibited at higher copper concentrations. At a lower concentration (0.1mgL(-1)), SOD activity increased in larvae, whereas CAT activity showed no significant change (p>0.05). MDA, as the lipid peroxidation product, gradually accumulated in embryos and larvae with increasing copper concentration and the extension of exposure time. At 0.4mgL(-1) and more, copper toxicity was shown in embryos and larvae. In conclusion, copper-exposed effects on hatching status and antioxidant defense in C. auratus embryos and larvae showed concentration- and time-dependent patterns. The biochemical parameters in this study can be used as effective indicators for evaluating the responses of copper-exposed fish embryos. In addition, this study demonstrates that 0.4mgL(-1) copper (corresponding to 1mgL(-1) copper sulfate), used to kill parasites in aquaculture, is not safe concentration, because it can result in toxicity to larvae. Therefore, the copper concentration to kill pathogen should be less than 0.4mgL(-1) for C. auratus.

  19. Coordinated response of sulfate transport, cysteine biosynthesis, and glutathione-mediated antioxidant defense in lentil (Lens culinaris Medik.) genotypes exposed to arsenic.

    PubMed

    Talukdar, Dibyendu; Talukdar, Tulika

    2014-07-01

    Response of sulfate transporters, thiol metabolism, and antioxidant defense system was studied in roots of two lentil (Lens culinaris Medik.) genotypes grown in arsenic (10, 25, and 40 μM As(V))-supplemented nutrient solution, and significant changes compared to control (0 μM As(V)) were observed mainly at 25 and 40 μM. In L 414, high glutathione (GSH) redox (0.8-0.9) was maintained with elevated thiol synthesis, powered by transcriptional up-regulation of LcSultr1;1 and LcSultr1;2 sulfate transporters and significant induction of LcSAT1;1 and LcSAT1;2 (serine acetyltransferase), OAS-TL (O-acetylserine(thiol)-lyase), γ-ECS (γ-glutamylcysteine synthetase), and PCS (phytochelatin synthase) genes predominantly within 12-24 h of As exposure at 25 μM and within 6-12 h at 40 μM. This thiolic potency in L 414 roots was effectively complemented by up-regulation of gene expressions and consequent enhanced activities of superoxide dismutase, ascorbate peroxidase (APX), dehydroascorbate reductase, glutathione reductase (GR), and glutathione-S-transferase (GST) isoforms at 25 and 40 μMAs, efficiently scavenging excess reactive oxygen species to prevent onset of As-induced oxidative stress and consequent inhibition of root growth in L 414. In contrast, down-regulation of vital sulfate-uptake transporters as well as entire thiol-metabolizing system and considerably low APX, GST, and GR expressions in DPL 59 not only resulted in reduced GSH redox but also led to over-accumulation of H2O2. This triggered membrane lipid peroxidations as the marks of As-induced oxidative damage. Results indicated coordinated response of thiol-metabolism and antioxidant defense in conferring As-tolerance in lentil, and GSH is the key point in this cascade.

  20. Antioxidant Defense Enzyme Genes and Asthma Susceptibility: Gender-Specific Effects and Heterogeneity in Gene-Gene Interactions between Pathogenetic Variants of the Disease

    PubMed Central

    Polonikov, Alexey V.; Ivanov, Vladimir P.; Bogomazov, Alexey D.; Freidin, Maxim B.; Illig, Thomas; Solodilova, Maria A.

    2014-01-01

    Oxidative stress resulting from an increased amount of reactive oxygen species and an imbalance between oxidants and antioxidants plays an important role in the pathogenesis of asthma. The present study tested the hypothesis that genetic susceptibility to allergic and nonallergic variants of asthma is determined by complex interactions between genes encoding antioxidant defense enzymes (ADE). We carried out a comprehensive analysis of the associations between adult asthma and 46 single nucleotide polymorphisms of 34 ADE genes and 12 other candidate genes of asthma in Russian population using set association analysis and multifactor dimensionality reduction approaches. We found for the first time epistatic interactions between ADE genes underlying asthma susceptibility and the genetic heterogeneity between allergic and nonallergic variants of the disease. We identified GSR (glutathione reductase) and PON2 (paraoxonase 2) as novel candidate genes for asthma susceptibility. We observed gender-specific effects of ADE genes on the risk of asthma. The results of the study demonstrate complexity and diversity of interactions between genes involved in oxidative stress underlying susceptibility to allergic and nonallergic asthma. PMID:24895604

  1. Nitrate reductase-mediated early nitric oxide burst alleviates oxidative damage induced by aluminum through enhancement of antioxidant defenses in roots of wheat (Triticum aestivum).

    PubMed

    Sun, Chengliang; Lu, Lingli; Liu, Lijuan; Liu, Wenjing; Yu, Yan; Liu, Xiaoxia; Hu, Yan; Jin, Chongwei; Lin, Xianyong

    2014-03-01

    • Nitric oxide (NO) is an important signaling molecule involved in the physiological processes of plants. The role of NO release in the tolerance strategies of roots of wheat (Triticum aestivum) under aluminum (Al) stress was investigated using two genotypes with different Al resistances. • An early NO burst at 3 h was observed in the root tips of the Al-tolerant genotype Jian-864, whereas the Al-sensitive genotype Yang-5 showed no NO accumulation at 3 h but an extremely high NO concentration after 12 h. Stimulating NO production at 3 h in the root tips of Yang-5 with the NO donor relieved Al-induced root inhibition and callose production, as well as oxidative damage and ROS accumulation, while elimination of the early NO burst by NO scavenger aggravated root inhibition in Jian-864. • Synthesis of early NO in roots of Jian-864 was mediated through nitrate reductase (NR) but not through NO synthase. Elevated antioxidant enzyme activities were induced by Al stress in both wheat genotypes and significantly enhanced by NO donor, but suppressed by NO scavenger or NR inhibitor. • These results suggest that an NR-mediated early NO burst plays an important role in Al resistance of wheat through modulating enhanced antioxidant defense to adapt to Al stress.

  2. O-GlcNAc protein modification in C2C12 myoblasts exposed to oxidative stress indicates parallels with endogenous antioxidant defense.

    PubMed

    Peternelj, Tina Tinkara; Marsh, Susan A; Morais, Christudas; Small, David M; Dalbo, Vincent J; Tucker, Patrick S; Coombes, Jeff S

    2015-02-01

    A growing body of evidence demonstrates the involvement of protein modification with O-linked β-N-acetylglucosamine (O-GlcNAc) in the stress response and its beneficial effects on cell survival. Here we investigated protein O-GlcNAcylation in skeletal muscle cells exposed to oxidative stress and the crosstalk with endogenous antioxidant system. The study focused on antioxidant enzymes superoxide dismutase 2 (SOD2), catalase (CAT), and glutathione peroxidase 1 (GPX1), and transcriptional regulators proliferator-activated receptor gamma coactivator 1-α (PGC-1α) and forkhead box protein O1 (FOXO1), which play important roles in oxidative stress response and are known to be O-GlcNAc-modified. C2C12 myoblasts were subjected to 24 h incubation with different reagents, including hydrogen peroxide, diethyl maleate, high glucose, and glucosamine, and the inhibitors of O-GlcNAc cycling enzymes. Surprisingly, O-GlcNAc levels were significantly increased only with glucosamine, whilst other treatments showed no effect. Significant changes at the mRNA level were observed with concomitant upregulation of the genes for O-GlcNAc enzymes and stress-related proteins with oxidizing agents and downregulation of these genes with agents promoting O-GlcNAcylation. Our findings suggest a role of O-GlcNAc in the stress response and indicate an inhibitory mechanism controlling O-GlcNAc levels in the muscle cells. This could represent an important homeostatic regulation of the cellular defense system.

  3. Polyamines Confer Salt Tolerance in Mung Bean (Vigna radiata L.) by Reducing Sodium Uptake, Improving Nutrient Homeostasis, Antioxidant Defense, and Methylglyoxal Detoxification Systems.

    PubMed

    Nahar, Kamrun; Hasanuzzaman, Mirza; Rahman, Anisur; Alam, Md Mahabub; Mahmud, Jubayer-Al; Suzuki, Toshisada; Fujita, Masayuki

    2016-01-01

    The physiological roles of PAs (putrescine, spermidine, and spermine) were investigated for their ability to confer salt tolerance (200 mM NaCl, 48 h) in mung bean seedlings (Vigna radiata L. cv. BARI Mung-2). Salt stress resulted in Na toxicity, decreased K, Ca, Mg, and Zn contents in roots and shoots, and disrupted antioxidant defense system which caused oxidative damage as indicated by increased lipid peroxidation, H2O2 content, [Formula: see text] generation rate, and lipoxygenase activity. Salinity-induced methylglyoxal (MG) toxicity was also clearly evident. Salinity decreased leaf chlorophyll (chl) and relative water content (RWC). Supplementation of salt affected seedlings with exogenous PAs enhanced the contents of glutathione and ascorbate, increased activities of antioxidant enzymes (dehydroascorbate reductase, glutathione reductase, catalase, and glutathione peroxidase) and glyoxalase enzyme (glyoxalase II), which reduced salt-induced oxidative stress and MG toxicity, respectively. Exogenous PAs reduced cellular Na content and maintained nutrient homeostasis and modulated endogenous PAs levels in salt affected mung bean seedlings. The overall salt tolerance was reflected through improved tissue water and chl content, and better seedling growth.

  4. Polyamines Confer Salt Tolerance in Mung Bean (Vigna radiata L.) by Reducing Sodium Uptake, Improving Nutrient Homeostasis, Antioxidant Defense, and Methylglyoxal Detoxification Systems

    PubMed Central

    Nahar, Kamrun; Hasanuzzaman, Mirza; Rahman, Anisur; Alam, Md. Mahabub; Mahmud, Jubayer-Al; Suzuki, Toshisada; Fujita, Masayuki

    2016-01-01

    The physiological roles of PAs (putrescine, spermidine, and spermine) were investigated for their ability to confer salt tolerance (200 mM NaCl, 48 h) in mung bean seedlings (Vigna radiata L. cv. BARI Mung-2). Salt stress resulted in Na toxicity, decreased K, Ca, Mg, and Zn contents in roots and shoots, and disrupted antioxidant defense system which caused oxidative damage as indicated by increased lipid peroxidation, H2O2 content, O2•- generation rate, and lipoxygenase activity. Salinity-induced methylglyoxal (MG) toxicity was also clearly evident. Salinity decreased leaf chlorophyll (chl) and relative water content (RWC). Supplementation of salt affected seedlings with exogenous PAs enhanced the contents of glutathione and ascorbate, increased activities of antioxidant enzymes (dehydroascorbate reductase, glutathione reductase, catalase, and glutathione peroxidase) and glyoxalase enzyme (glyoxalase II), which reduced salt-induced oxidative stress and MG toxicity, respectively. Exogenous PAs reduced cellular Na content and maintained nutrient homeostasis and modulated endogenous PAs levels in salt affected mung bean seedlings. The overall salt tolerance was reflected through improved tissue water and chl content, and better seedling growth. PMID:27516763

  5. Effect of garlic (Allium sativum) on hematology and erythrocyte antioxidant defense system of albino rats exposed to heavy metals (nickel II & chromium VI).

    PubMed

    Tikare, Swati N; Yendigeri, Saeed; Gupta, Amrita Das; Dhundasi, Salim A; Das, Kusal K

    2012-01-01

    Heavy metals are stable environmental contaminants, causing various alterations in target tissues. Garlic has some beneficial effect in preventing heavy metal induced various alteration. The objective was to investigate the possible protective role of fresh aqueous homogenate of garlic on hematology, erythrocyte antioxidant defense system in male albino rats treated with NiSO4 and K2Cr2O7. Rats were divided into six groups. Group I was untreated control. Group II was given aqueous homogenate of garlic (orally). Group III was administered with nickel sulfate (i.p). Group IV was given NiSO4 and garlic simultaneously. Group V was administered with K2Cr2O7 (i.p). Group VI were treated simultaneously with K2Cr2O7 and garlic. RBC, WBC, platelet count, PCV%, hemoglobin concentration decreased significantly and clotting time increased significantly after nickel treatment. After chromium treatment all the values decreased except clotting time. Increased malondialdehyde and glutathione level after nickel and chromium treatment was observed. Also erythrocyte superoxide dismutase, glutathione peroxidase and catalase activities significantly increased after nickel and chromium treatment. Simultaneous garlic supplementation exhibited protective role to combat nickel toxicity, whereas no such beneficial effects were observed for chromium (VI). Garlic may partially prevent nickel and chromium induced alteration but such ameliorated effects as an antioxidant is only restricted on nickel induced alteration.

  6. Cannabidiol Post-Treatment Alleviates Rat Epileptic-Related Behaviors and Activates Hippocampal Cell Autophagy Pathway Along with Antioxidant Defense in Chronic Phase of Pilocarpine-Induced Seizure.

    PubMed

    Hosseinzadeh, Mahshid; Nikseresht, Sara; Khodagholi, Fariba; Naderi, Nima; Maghsoudi, Nader

    2016-04-01

    Abnormal and sometimes severe behavioral and molecular symptoms are usually observed in epileptic humans and animals. To address this issue, we examined the behavioral and molecular aspects of seizure evoked by pilocarpine. Autophagy can promote both cell survival and death, but there are controversial reports about the neuroprotective or neurodegenerative effects of autophagy in seizure. Cannabidiol has anticonvulsant properties in some animal models when used as a pretreatment. In this study, we investigated alteration of seizure scores, autophagy pathway proteins, and antioxidant status in hippocampal cells during the chronic phase of pilocarpine-induced epilepsy after treatment with cannabidiol. Cannabidiol (100 ng, intracerebroventricular injection) delayed the chronic phase of epilepsy. Single administration of cannabidiol during the chronic phase of seizure significantly diminished seizure scores such as mouth clonus, head nodding, monolateral and bilateral forelimb clonus and increased the activity of catalase enzyme and reduced glutathione content. Such a protective effect in the behavioral scores of epileptic rats was also observed after repeated administrations of cannabidiol at the onset of the silent phase. Moreover, the amount of Atg7, conjugation of Atg5/12, Atg12, and LC3II/LC3I ratio increased significantly in epileptic rats treated with repeated injections of cannabidiol. In short, our results suggest that post-treatment of Cannabidiol could enhance the induction of autophagy pathway and antioxidant defense in the chronic phase of epilepsy, which could be considered as the protective mechanisms of cannabidiol in a temporal lobe epilepsy model.

  7. Allocation of cysteine for glutathione production in caterpillars with different antioxidant defense strategies: a comparison of Lymantria dispar and Malacosoma disstria.

    PubMed

    Barbehenn, Raymond V; Kochmanski, Joseph; Menachem, Brandon; Poirier, Lisa M

    2013-10-01

    Sulfur amino acids [cysteine (Cys) and methionine (Met)] play two major roles during animal development: protein synthesis for growth and glutathione synthesis for defense. For caterpillars, the levels of sulfur amino acids found in foliar protein can be especially low relative to their nutritional needs. Previous work has measured concentrations of glutathione (GSH; containing Cys) in specific animal tissues, but has not examined whole-body levels to ascertain the costliness of this defense in terms of Cys allocation. This study examined whether the production of GSH varies between species and within individuals in accordance with an insect's need for antioxidant defense. Secondly, we quantified the allocation of total Cys (peptide-bound plus free Cys) to GSH in caterpillars as an estimate of its cost. Two contrasting species were compared: Lymantria dispar (Lymantriidae), a species that is highly defended, and Malacosoma disstria (Lasiocampidae), a species that is less defended. As expected, GSH levels were significantly higher in L. dispar than in M. disstria. Consistent with the function of the midgut as a first line of defense against ingested toxins, GSH levels were significantly higher in these tissues than in the whole bodies of both species. A major finding in this study was that a large fraction of total Cys is used to produce GSH: GSH in the midguts of L. dispar and M. disstria contained 23 and 21%, respectively, of the total Cys in these tissues, and the GSH in their remaining body tissues contained 19 and 17% of the total Cys in these tissues. Levels of total Cys in caterpillar tissues followed the same pattern of distribution as did GSH, producing a strong association between GSH and total Cys (R(2) = 0.794). We conclude that GSH is a costly defense, especially in generalist tree-feeding species such as L. dispar. These results further suggest that the large allocation of Cys to GSH in highly defended species might produce a tradeoff by limiting the

  8. Salicylic acid alleviates cadmium-induced inhibition of growth and photosynthesis through upregulating antioxidant defense system in two melon cultivars (Cucumis melo L.).

    PubMed

    Zhang, Yongping; Xu, Shuang; Yang, Shaojun; Chen, Youyuan

    2015-05-01

    Cadmium (Cd) is a widespread toxic heavy metal that usually causes deleterious effects on plant growth and development. Salicylic acid (SA), a naturally existing phenolic compound, is involved in specific responses to various environmental stresses. To explore the role of SA in the tolerance of melon (Cucumis melo L.) to Cd stress, the influence of SA application on the growth and physiological processes was compared in the two melon cultivars Hamilv (Cd-tolerant) and Xiulv (Cd-sensitive) under Cd stress. Under 400-μM Cd treatment, Hamilv showed a higher biomass accumulation, more chlorophyll (Chl), greater photosynthesis, and less oxidative damage compared to Xiulv. Foliar spraying of 0.1 mM SA dramatically alleviated Cd-induced growth inhibition in the two melon genotypes. Simultaneously, SA pretreatment attenuated the decrease in Chl content, photosynthetic capacity, and PSII photochemistry efficiency in Cd-stressed plants. Furthermore, exogenous SA significantly reduced superoxide anion production and lipid peroxidation, followed by increase in the activities of antioxidant enzyme superoxide dismutase, guaiacol peroxidase, catalase, and ascorbate peroxidase, and content of soluble protein and free proline in both the genotypes under Cd stress. The effect of SA was more conspicuous in Xiulv than Hamilv, reflected in the biomass, photosynthetic pigments, stomatal conductance, water use efficiency, and antioxidant enzymes. These results suggest that exogenous spray of SA can alleviate the adverse effects of Cd on the growth and photosynthesis of both the melon cultivars, mostly through promoting antioxidant defense capacity. It also indicates that SA-included protection against Cd damage is to a greater extent more pronounced in Cd-sensitive genotype than Cd-tolerant genotype.

  9. Ulva lactuca polysaccharides prevent Wistar rat breast carcinogenesis through the augmentation of apoptosis, enhancement of antioxidant defense system, and suppression of inflammation

    PubMed Central

    Abd-Ellatef, Gamal-Eldein F; Ahmed, Osama M; Abdel-Reheim, Eman S; Abdel-Hamid, Abdel-Hamid Z

    2017-01-01

    . These preventive effects may be mediated through the augmentation of apoptosis, suppression of oxidative stress and inflammation, and enhancement of antioxidant defense system. PMID:28280387

  10. The association of enzymatic and non-enzymatic antioxidant defense parameters with inflammatory markers in patients with exudative form of age-related macular degeneration

    PubMed Central

    Čolak, Emina; Ignjatović, Svetlana; Radosavljević, Aleksandra; Žorić, Lepša

    2017-01-01

    There are evidence that oxidative stress and inflammation are involved in the pathogenesis of the age-related macular degeneration (AMD). The aim of this study was to analyze the antioxidant defense parameters and inflammatory markers in patients with exudative form of AMD (eAMD), their mutual correlations and association with the specific forms of AMD. The cross-sectional study, included 75 patients with the eAMD, 31 patients with the early form, and 87 aged-matched control subjects. Significantly lower SOD, TAS and albumin values and higher GR, CRP and IL-6 were found in the eAMD compared to the early form (p<0.05). Significant negative correlations were found between GPx and fibrinogen (r = –0.254), TAS and IL-6 (r = –0.999) and positive correlations between uric acid and CRP (r = 0.292), IL-6 and uric acid (r = 0.398) in the eAMD. A significant association of CRP (OR: 1.16, 95% CI: 1.03–1.32, p = 0.018), fibrinogen (OR: 2.21, 95% CI: 1.14–4.85, p = 0.021), TAS (OR: 7.45, 95% CI: 3.97–14.35, p = 0.0001), albumin (OR: 1.25, 95% CI: 1.11–1.41, p = 0.0001) and uric acid (OR: 1.006, 95% CI: 1.00–1.02, p = 0.003) was found with the eAMD. In conclusion it may be suggested, there is a significant impairment of antioxidant and inflammatory parameter levels in eAMD patients. In addition, significant association exists between the tested inflammatory markers and antioxidant parameters with late-eAMD. PMID:28366988

  11. Genetic and Pharmacologic Targeting of Glycogen Synthase Kinase 3β Reinforces the Nrf2 Antioxidant Defense against Podocytopathy.

    PubMed

    Zhou, Sijie; Wang, Pei; Qiao, Yingjin; Ge, Yan; Wang, Yingzi; Quan, Songxia; Yao, Ricky; Zhuang, Shougang; Wang, Li Juan; Du, Yong; Liu, Zhangsuo; Gong, Rujun

    2016-08-01

    Evidence suggests that the glycogen synthase kinase 3 (GSK3)-dictated nuclear exclusion and degradation of Nrf2 is pivotal in switching off the self-protective antioxidant stress response after injury. Here, we examined the mechanisms underlying this regulation in glomerular disease. In primary podocytes, doxorubicin elicited cell death and actin cytoskeleton disorganization, concomitant with overactivation of GSK3β (the predominant GSK3 isoform expressed in glomerular podocytes) and minimal Nrf2 activation. SB216763, a highly selective small molecule inhibitor of GSK3, exerted a protective effect that depended on the potentiated Nrf2 antioxidant response, marked by increased Nrf2 expression and nuclear accumulation and augmented production of the Nrf2 target heme oxygenase-1. Ectopic expression of the kinase-dead mutant of GSK3β in cultured podocytes reinforced the doxorubicin-induced Nrf2 activation and prevented podocyte injury. Conversely, a constitutively active GSK3β mutant blunted the doxorubicin-induced Nrf2 response and exacerbated podocyte injury, which could be abolished by treatment with SB216763. In murine models of doxorubicin nephropathy or nephrotoxic serum nephritis, genetic targeting of GSK3β by doxycycline-inducible podocyte-specific knockout or pharmacologic targeting by SB216763 significantly attenuated albuminuria and ameliorated histologic signs of podocyte injury, including podocytopenia, loss of podocyte markers, podocyte de novo expression of desmin, and ultrastructural lesions of podocytopathy (such as foot process effacement). This beneficial outcome was likely attributable to an enhanced Nrf2 antioxidant response in glomerular podocytes because the selective Nrf2 antagonist trigonelline abolished the proteinuria-reducing and podocyte-protective effect. Collectively, our results suggest the GSK3β-regulated Nrf2 antioxidant response as a novel therapeutic target for protecting podocytes and treating proteinuric glomerulopathies.

  12. Melatonin, a potent agent in antioxidative defense: Actions as a natural food constituent, gastrointestinal factor, drug and prodrug

    PubMed Central

    Hardeland, Rüdiger; Pandi-Perumal, SR

    2005-01-01

    Melatonin, originally discovered as a hormone of the pineal gland, is also produced in other organs and represents, additionally, a normal food constituent found in yeast and plant material, which can influence the level in the circulation. Compared to the pineal, the gastrointestinal tract contains several hundred times more melatonin, which can be released into the blood in response to food intake and stimuli by nutrients, especially tryptophan. Apart from its use as a commercial food additive, supraphysiological doses have been applied in medical trials and pure preparations are well tolerated by patients. Owing to its amphiphilicity, melatonin can enter any body fluid, cell or cell compartment. Its properties as an antioxidant agent are based on several, highly diverse effects. Apart from direct radical scavenging, it plays a role in upregulation of antioxidant and downregulation of prooxidant enzymes, and damage by free radicals can be reduced by its antiexcitatory actions, and presumably by contributions to appropriate internal circadian phasing, and by its improvement of mitochondrial metabolism, in terms of avoiding electron leakage and enhancing complex I and complex IV activities. Melatonin was shown to potentiate effects of other antioxidants, such as ascorbate and Trolox. Under physiological conditions, direct radical scavenging may only contribute to a minor extent to overall radical detoxification, although melatonin can eliminate several of them in scavenger cascades and potentiates the efficacy of antioxidant vitamins. Melatonin oxidation seems rather important for the production of other biologically active metabolites such as N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK) and N1-acetyl-5-methoxykynuramine (AMK), which have been shown to also dispose of protective properties. Thus, melatonin may be regarded as a prodrug, too. AMK interacts with reactive oxygen and nitrogen species, conveys protection to mitochondria, inhibits and downregulates

  13. Pulmonary antioxidants

    SciTech Connect

    Massaro, E.J.; Grose, E.C.; Hatch, G.E.; Slade, R.

    1987-05-01

    One of the most vital of the cellular defenses against pollution is an antioxidant armanentarium which consists of oxidant scavenging molecules such as vitamin E, glutathione, vitamin C, and uric acid as well as a number of enzymes (superoxide dismutase, semidehydroascorbate reductase, catalase, GSH synthetase, GSH peroxidase, GSH reductase, and GSH transferase) and appears to function in keeping oxidant forces under control. Pollutants can upset the oxidant/antioxidant balance of cells by inhibiting vital enzymes, by reacting with oxidant scavengers, or by forming free radical intermediates which initiate uncontrolled tissue reactions with molecular oxygen. The book chapter reviews possible interactions between pollutants and the oxidant/antioxidant balance.

  14. Hydrogen Peroxide Pretreatment Mitigates Cadmium-Induced Oxidative Stress in Brassica napus L.: An Intrinsic Study on Antioxidant Defense and Glyoxalase Systems

    PubMed Central

    Hasanuzzaman, Mirza; Nahar, Kamrun; Gill, Sarvajeet S.; Alharby, Hesham F.; Razafindrabe, Bam H. N.; Fujita, Masayuki

    2017-01-01

    Cadmium (Cd) is considered as one of the most toxic metals for plant growth and development. In the present study, we investigated the role of externally applied hydrogen peroxide (H2O2) in regulating the antioxidant defense and glyoxalase systems in conferring Cd-induced oxidative stress tolerance in rapeseed (Brassica napus L.). Seedlings were pretreated with 50 μM H2O2 for 24 h. These pretreated seedlings as well as non-pretreated seedlings were grown for another 48 h at two concentrations of CdCl2 (0.5 and 1.0 mM). Both the levels of Cd increased MDA and H2O2 levels and lipoxygenase activity while ascorbate (AsA) declined significantly. However, reduced glutathione (GSH) content showed an increase at 0.5 mM CdCl2, but glutathione disulfide (GSSG) increased at any level of Cd with a decrease in GSH/GSSG ratio. The activities of ascorbate peroxidase (APX) and glutathione S-transferase (GST) upregulated due to Cd treatment in dose-dependent manners, while glutathione reductase (GR) and glutathione peroxidase (GPX) increased only at 0.5 mM CdCl2 and decreased at higher dose. The activity of monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT), glyoxalase I (Gly I), and glyoxalase II (Gly II) decreased under Cd stress. On the other hand, H2O2 pretreated seedlings, when exposed to Cd, AsA and GSH contents and GSH/GSSG ratio increased noticeably. H2O2 pretreatment increased the activities of APX, MDHAR, DHAR, GR, GST, GPX, and CAT of Cd affected seedlings. Thus enhancement of both the non-enzymatic and enzymatic antioxidants helped to decrease the oxidative damage as indicated by decreased levels of H2O2 and MDA. The seedlings which were pretreated with H2O2 also showed enhanced glyoxalase system. The activities of Gly I, and Gly II and the content of GSH increased significantly due to H2O2 pretreatment in Cd affected seedlings, compared to the Cd-stressed plants without H2O2 pretreatment which were vital for methylglyoxal

  15. Curcuma purpurascens BI. rhizome accelerates rat excisional wound healing: involvement of Hsp70/Bax proteins, antioxidant defense, and angiogenesis activity

    PubMed Central

    Rouhollahi, Elham; Moghadamtousi, Soheil Zorofchian; Hajiaghaalipour, Fatemeh; Zahedifard, Maryam; Tayeby, Faezeh; Awang, Khalijah; Abdulla, Mahmood Ameen; Mohamed, Zahurin

    2015-01-01

    Purpose Curcuma purpurascens BI. is a member of Zingiberaceae family. The purpose of this study is to investigate the wound healing properties of hexane extract of C. purpurascens rhizome (HECP) against excisional wound healing in rats. Materials and methods Twenty four rats were randomly divided into 4 groups: A) negative control (blank placebo, acacia gum), B) low dose of HECP, C) high dose of HECP, and D) positive control, with 6 rats in each group. Full-thickness incisions (approximately 2.00 cm) were made on the neck area of each rat. Groups 1–4 were treated two-times a day for 20 days with blank placebo, HECP (100 mg/kg), HECP (200 mg/kg), and intrasite gel as a positive control, respectively. After 20 days, hematoxylin and eosin and Masson’s trichrome stainings were employed to investigate the histopathological alterations. Protein expressions of Bax and Hsp70 were examined in the wound tissues using immunohistochemistry analysis. In addition, levels of enzymatic antioxidants and malondialdehyde representing lipid peroxidation were measured in wound tissue homogenates. Results Macroscopic evaluation of wounds showed conspicuous elevation in wound contraction after topical administration of HECP at both doses. Moreover, histopathological analysis revealed noteworthy reduction in the scar width correlated with the enhanced collagen content and fibroblast cells, accompanied by a reduction of inflammatory cells in the granulation tissues. At the molecular level, HECP facilitates wound-healing process by downregulating Bax and upregulating Hsp70 protein at the wound site. The formation of new blood vessel was observed in Masson’s trichrome staining of wounds treated with HECP (100 and 200 mg/kg). In addition, HECP administration caused a significant surge in enzymatic antioxidant activities and a decline in lipid peroxidation. Conclusion These findings suggested that HECP accelerated wound-healing process in rats via antioxidant activity, angiogenesis

  16. Growth and antioxidant defense responses of wheat seedlings to di-n-butyl phthalate and di (2-ethylhexyl) phthalate stress.

    PubMed

    Gao, Minling; Dong, Youming; Zhang, Ze; Song, Wenhua; Qi, Yun

    2017-04-01

    Phthalate acid esters (PAEs) are vital environmental hormone-like chemicals that are noxious to plants, animals, and human beings. In this study, the influences of di-n-butyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP) on the seed germination, root morphology, and various physiological changes of wheat seedlings were investigated by analyzing superoxide anion (O2(-)) accumulation, antioxidant enzyme activity, and lipid peroxidation. DBP and DEHP were found to obviously inhibit germination only at high concentrations, but significantly affected root morphology even at lower concentrations. Their toxic effects were the most severe on root elongation, followed by shoot elongation, and were the least severe on germination rate, indicating that root elongation was the best index for evaluating DBP and DEHP eco-toxicity. DBP and DEHP also enhanced O2(-) and malondialdehyde levels and membrane permeability, as well as produced changes in the antioxidant status and PAE content in the stem and leaf (combined tissues, hereafter shoot) and root tissues. The activities of superoxide dismutase, catalase, and peroxidase increased at low and medium DBP and DEHP concentrations, but declined at high PAE concentrations. These results indicated that PAEs could exert oxidative damage in the early development stage of wheat, particularly at higher concentrations. DBP and DEHP accumulation was higher in the roots than in the shoot tissues, and their levels in these tissues increased with increasing PAE concentrations, supporting their more-serious toxic effects on roots than those on shoots. Further, the physicochemical properties of DBP rendered it more harmful than DEHP.

  17. Cytotoxic effects of zearalenone and its metabolites and antioxidant cell defense in CHO-K1 cells.

    PubMed

    Tatay, Elena; Font, Guillermina; Ruiz, Maria-Jose

    2016-10-01

    Zearalenone (ZEA) and its metabolites (α-zearalenol; α-ZOL, β-zearalenol; β-ZOL) are secondary metabolites of Fusarium fungi that produce cell injury. The present study explores mycotoxin-induced cell damage and cellular protection mechanisms in CHO-K1 cells. Cytotoxicity has been determined by reactive oxygen species (ROS) production and DNA damage. ROS production was determined using the fluorescein assay and DNA strand breakage by comet assay. Intracellular protection systems were glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD). The results demonstrated that all mycotoxins increased the ROS levels up to 5.3-fold the control levels in CHO-K1 cells. Zearalenone metabolites, but not ZEA, increased DNA damage 43% (α-ZOL) and 28% (β-ZOL) compared to control cells. The GSH levels decreased from 18% to 36%. The GPx and SOD activities respectively increased from 26% to 62% and from 23% to 69% in CHO-K1 cells, whereas CAT activity decreased from 14% to 52%. In addition, intracellular ROS production was induced by ZEA and its metabolites. The endogenous antioxidant system components GSH, GPx and SOD were activated against ZEA and its metabolites. These antioxidant system components thus could contribute to decrease cell injury by ZEA and its metabolites.

  18. Responses of antioxidant defense system to polyfluorinated dibenzo-p-dioxins (PFDDs) exposure in liver of freshwater fish Carassius auratus.

    PubMed

    Li, Chenguang; Qin, Li; Qu, Ruijuan; Sun, Ping; Wang, Zunyao

    2016-04-01

    In this study, we evaluated the toxicity of ten polyfluorinated dibenzo-p-dioxins (PFDDs) congeners to freshwater fish Carassius auratus, by determining the antioxidative responses and lipid peroxidation in the liver after the fish were injected with two different concentrations (10 and 100 µmol/kg) of individual PFDDs for 3 and 14 days. The results showed that oxidative stress was obviously induced in some PFDDs-treated groups, as implied by the significantly inhibited antioxidants levels (superoxide dismutase, catalase, reduced glutathione, and glutathione S-transferase) and elevated malondialdehyde content. In addition, the oxidative stress inducing ability was variable for different PFDDs congeners, which was related with the substitution number and position of fluorine atom. Based on the calculated integrated biomarker response (IBR) values, the toxicity was ranked as 2,3,7,8-FDD>Octa-FDD>1,2,3,4,7-FDD>1,3,6,8-FDD>1,2,3,4,6,7-FDD>1,2,6,7-FDD>1,2,7-FDD>DD>2,7-FDD>2-FDD. This study can enhance the general understanding of the PFDDs induced oxidative stress in aquatic organisms.

  19. Cadmium-induced alterations in the antioxidant defense system of the rat eye in relation to dietary selenium intake

    SciTech Connect

    Sinno, J.A.M.

    1989-01-01

    Studies were conducted to investigate the effects of dietary cadmium (Cd)upon enzymatic antioxidant function in the ocular tissues of the albino rat. Activity of glutathione peroxidase (GSH-Px), Se-independent GSH-Px and catalase, and concentrations of thiobarbituric acid-reactive substances (TBARS), glutathione, and the elements Se, Cd and copper (Cu) were determined in ocular tissues from each group. Feeding rats a low Se diet resulted in a significant decrease in GSH-Px activity irrespective of Cd treatment. Activity of Se-independent GSH-Px in rats maintained on the low Se diet decreased when compared to Se-adequate controls. Cd treatment of rats fed low Se resulted in increased activity when compared to low-Se controls. When comparisons were made between ocular TBARS in rats maintained at either level of dietary Se, with or without Cd treatment, decreased ocular TBARS were observed in Cd-treated groups. A significant decrease in the ocular concentration of Se occurred in rats fed 0.05 ppm Se when compared to rats supplemented with 0.10 ppm Se. Administering Cd to the low Se group increased ocular Se levels 100%. A negative correlation between ocular Se concentration and the level of TBARS was observed, suggesting a possible alternate role for Se as an antioxidant in the eye.

  20. Flesh Quality Loss in Response to Dietary Isoleucine Deficiency and Excess in Fish: A Link to Impaired Nrf2-Dependent Antioxidant Defense in Muscle

    PubMed Central

    Gan, Lu; Jiang, Wei-Dan; Wu, Pei; Liu, Yang; Jiang, Jun; Li, Shu-Hong; Tang, Ling; Kuang, Sheng-Yao; Feng, Lin; Zhou, Xiao-Qiu

    2014-01-01

    The present study explored the impact of dietary isoleucine (Ile) on fish growth and flesh quality and revealed a possible role of muscle antioxidant defense in flesh quality in relation to dietary Ile. Grass carp (weighing 256.8±3.5 g) were fed diets containing six graded levels of Ile (3.8, 6.6, 9.3, 12.5, 15.2 and 18.5 g/kg) for eight weeks. The results indicated that compared with Ile deficiency (3.8 g/kg diets) and excess (18.5 g/kg diets) groups, 9.3–15.2 g Ile/kg diet supplementations promoted fish growth and muscle fat deposition, whereas 6.6–15.2 g Ile/kg diets supplementation enhanced muscle nutrients (protein and total EAAs) deposition. Furthermore, muscle shear force, pH value, and hydroxyproline concentration were improved by 9.3–12.5, 9.3 and 9.3 g Ile/kg diet supplementations, respectively. However, muscle cooking loss, lactate content, and activities of cathepsin B and L were decreased by 6.6–15.2, 9.3–12.5, 9.3–12.5 and 9.3–15.2 g Ile/kg diet supplementations, respectively. Additionally, 6.6–15.2 and 6.6–12.5 g Ile/kg diet supplementations attenuated malondialdehyde and protein carbonyl contents, respectively. The activities of copper/zinc superoxide dismutase (Cu/Zn-SOD) and glutathione peroxidase (GPx), and glutathione content were enhanced by 6.6–9.3, 6.6–12.5 and 6.6–15.2 g Ile/kg diet supplementations, respectively. Moreover, the relative mRNA expressions of antioxidant enzymes, including Cu/Zn-SOD (6.6–12.5 g/kg diets) and GPx (12.5 g/kg diets), as well as antioxidant-related signaling molecules, including NF-E2-related factor 2 (Nrf2) (6.6–12.5 g/kg diets), target of rapamycin (6.6–12.5 g/kg diets), ribosomal S6 protein kinase 1 (9.3–12.5 g/kg diets) and casein kinase 2 (6.6–12.5 g/kg diets), were up-regulated when Ile diet supplementations were administered at these levels, respectively, whereas the relative mRNA expression of Kelch-like ECH-associated protein 1 was down-regulated with 9.3 g Ile/kg diet

  1. Application of Plant-Growth-Promoting Fungi Trichoderma longibrachiatum T6 Enhances Tolerance of Wheat to Salt Stress through Improvement of Antioxidative Defense System and Gene Expression.

    PubMed

    Zhang, Shuwu; Gan, Yantai; Xu, Bingliang

    2016-01-01

    Soil salinity is a serious problem worldwide that reduces agricultural productivity. Trichoderma longibrachiatum T6 (T6) has been shown to promote wheat growth and induce plant resistance to parasitic nematodes, but whether the plant-growth-promoting fungi T6 can enhance plant tolerance to salt stress is unknown. Here, we determined the effect of plant-growth-promoting fungi T6 on wheat seedlings' growth and development under salt stress, and investigated the role of T6 in inducing the resistance to NaCl stress at physiological, biochemical, and molecular levels. Wheat seedlings were inoculated with the strain of T6 and then compared with non-inoculated controls. Shoot height, root length, and shoot and root weights were measured on 15 days old wheat seedlings grown either under 150 mM NaCl or in a controlled setting without any NaCl. A number of colonies were re-isolated from the roots of wheat seedlings under salt stress. The relative water content in the leaves and roots, chlorophyll content, and root activity were significantly increased, and the accumulation of proline content in leaves was markedly accelerated with the plant growth parameters, but the content of leaf malondialdehyde under saline condition was significantly decreased. The antioxidant enzymes-superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in wheat seedlings were increased by 29, 39, and 19%, respectively, with the application of the strain of T6 under salt stress; the relative expression of SOD, POD, and CAT genes in these wheat seedlings were significantly up-regulated. Our results indicated that the strain of T6 ameliorated the adverse effects significantly, protecting the seedlings from salt stress during their growth period. The possible mechanisms by which T6 suppresses the negative effect of NaCl stress on wheat seedling growth may be due to the improvement of the antioxidative defense system and gene expression in the stressed wheat plants.

  2. Effect of fraxetin on antioxidant defense and stress proteins in human neuroblastoma cell model of rotenone neurotoxicity. Comparative study with myricetin and N-acetylcysteine

    SciTech Connect

    Molina-Jimenez, Maria Francisca . E-mail: jbenedi@farm.ucm.es

    2005-12-15

    Mitochondrial complex I inhibitor rotenone induces apoptosis through enhancing mitochondrial reactive oxygen species production. Recently, it has been shown that fraxetin (coumarin) and myricetin (flavonoid) have significant neuroprotective effects against apoptosis induced by rotenone, increase the total glutathione levels in vitro, and inhibit lipid peroxidation. Thus, these considerations prompted us to investigate the way in which fraxetin and myricetin affect the endogenous antioxidant defense system, such as Mn and CuZn superoxide dismutase (MnSOD, CuZnSOD), catalase, glutathione reductase (GR), and glutathione peroxidase (GPx) on rotenone neurotoxicity in neuroblastoma cells. N-acetylcysteine (NAC), a potent antioxidant, was employed as a comparative agent. Also, the expression and protein levels of HSP70 by Northern and Western blot analysis were assayed in SH-SY5Y cells. After incubation for 16 h, rotenone significantly increased the expression and activity of MnSOD, GPx, and catalase. When cells were preincubated with fraxetin, there was a decrease in the protein levels and activity of both MnSOD and catalase, in comparison with the rotenone treatment. The myricetin effect was less pronounced. Activity and expression of GPx were increased by rotenone and pre-treatment with fraxetin did not modify significantly these levels. The significant enhancement in HSP70 expression at mRNA and protein levels induced by fraxetin was observed by pre-treatment of cells 0.5 h before rotenone insult. These data suggest that major features of rotenone-induced neurotoxicity are partially mediated by free radical formation and oxidative stress, and that fraxetin partially protects against rotenone toxicity affecting the main protection system of the cells against oxidative injury.

  3. Goldfish exposure to cobalt enhances hemoglobin level and triggers tissue-specific elevation of antioxidant defenses in gills, heart and spleen.

    PubMed

    Kubrak, Olga I; Rovenko, Bohdana M; Husak, Viktor V; Vasylkiv, Olena Yu; Storey, Kenneth B; Storey, Janet M; Lushchak, Volodymyr I

    2012-03-01

    Cobalt ions can enhance the generation of reactive oxygen species (ROS), which may be the reason for cobalt toxicity. This study aimed to determine whether Co(2+) toxicity in goldfish is related to induced oxidative stress in gills, heart and spleen, and to assess responses of antioxidant systems. Exposure of goldfish to 50, 100 and 150 mg L(-1) of Co(2+) for 96 h elevated total hemoglobin in blood by 23, 44 and 78%, respectively. In gills, cobalt exposure enhanced lipid peroxide levels and activities of primary antioxidant enzymes; superoxide dismutase (SOD) rose by 125% and glutathione peroxidase (GPx) increased by 53-296%. Glutathione-S-transferase (GST) activity also increased by 117-157% and glucose-6-phosphate dehydrogenase (G6PDH) enhanced by 46-96%. Heart showed limited effects of fish exposure to 50 or 100 mg L(-1) of Co(2+), but the exposure to 150 mg L(-1) of Co(2+) elevated concentrations of lipid peroxides by 123% and activities of GPx by 98% and SOD by 208%. The most substantial effects of goldfish exposure to Co(2+) were observed in spleen: a decrease in total protein concentration by 44-60% and high molecular mass thiols by 59-82%, reduced activities of catalase by 24-58% and GR by 25-68%, whereas the level of low molecular mass thiols increased by 153-279% and activities of GPx, GST, G6PDH were enhanced by 114-120%, 192-769%, and 256-581%, respectively. The data show that fish exposure to 50-150 mg L(-1) of Co(2+) elevates blood hemoglobin level, mimicking effects of hypoxia, and causes the activation of defense systems against ROS.

  4. Application of Plant-Growth-Promoting Fungi Trichoderma longibrachiatum T6 Enhances Tolerance of Wheat to Salt Stress through Improvement of Antioxidative Defense System and Gene Expression

    PubMed Central

    Zhang, Shuwu; Gan, Yantai; Xu, Bingliang

    2016-01-01

    Soil salinity is a serious problem worldwide that reduces agricultural productivity. Trichoderma longibrachiatum T6 (T6) has been shown to promote wheat growth and induce plant resistance to parasitic nematodes, but whether the plant-growth-promoting fungi T6 can enhance plant tolerance to salt stress is unknown. Here, we determined the effect of plant-growth-promoting fungi T6 on wheat seedlings’ growth and development under salt stress, and investigated the role of T6 in inducing the resistance to NaCl stress at physiological, biochemical, and molecular levels. Wheat seedlings were inoculated with the strain of T6 and then compared with non-inoculated controls. Shoot height, root length, and shoot and root weights were measured on 15 days old wheat seedlings grown either under 150 mM NaCl or in a controlled setting without any NaCl. A number of colonies were re-isolated from the roots of wheat seedlings under salt stress. The relative water content in the leaves and roots, chlorophyll content, and root activity were significantly increased, and the accumulation of proline content in leaves was markedly accelerated with the plant growth parameters, but the content of leaf malondialdehyde under saline condition was significantly decreased. The antioxidant enzymes-superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in wheat seedlings were increased by 29, 39, and 19%, respectively, with the application of the strain of T6 under salt stress; the relative expression of SOD, POD, and CAT genes in these wheat seedlings were significantly up-regulated. Our results indicated that the strain of T6 ameliorated the adverse effects significantly, protecting the seedlings from salt stress during their growth period. The possible mechanisms by which T6 suppresses the negative effect of NaCl stress on wheat seedling growth may be due to the improvement of the antioxidative defense system and gene expression in the stressed wheat plants. PMID:27695475

  5. Effect of Zinc Supplementation on Antioxidant Defenses and Oxidative Stress Markers in Patients Undergoing Chemotherapy for Colorectal Cancer: a Placebo-Controlled, Prospective Randomized Trial.

    PubMed

    Ribeiro, Sofia Miranda de Figueiredo; Braga, Camila Bitu Moreno; Peria, Fernanda Maris; Domenici, Fernanda Aparecida; Martinez, Edson Zangiacomi; Feres, Omar; da Rocha, José Joaquim Ribeiro; da Cunha, Selma Freire de Carvalho

    2016-01-01

    The study aimed to investigate the effect of oral zinc supplementation on antioxidant defenses and oxidative stress markers during chemotherapy for colorectal cancer. Twenty-four patients who had undergone surgical resection of colorectal cancer participated in this placebo-controlled, prospective randomized study. The supplementation was started in the perioperative period, in which 10 patients received 70 mg of zinc (zinc group, n = 10) and 14 patients received placebo (placebo group, n = 14) for 16 weeks. Approximately 45 days after surgical resection of tumor, all patients received a chemotherapeutic regimen (capecitabine, capecitabine combined with oxaliplatin or 5-fluorouracil). Vitamin C, vitamin E, antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), and lipid peroxidation markers malondialdehyde (MDA) and 8-isoprostane were determined before the first, second, third, and fourth chemotherapy cycles. Compared with the placebo group, the zinc group presented higher SOD values before the first, second, and fourth chemotherapy cycles and lower GPx values before the third cycle. There were no statistical differences between the study groups in vitamin C, vitamin E, MDA, or 8-isoprostane plasma values. Longitudinal analysis revealed decreased vitamin E concentration in the placebo group before the second and fourth cycles as compared with the initial values. Zinc supplementation during chemotherapy cycles increased SOD activity and maintained vitamin E concentrations. Although no effect of zinc supplementation on oxidative stress markers was observed, the increase in SOD activity indicates a production of stable free radicals, which may have a positive effect in cancer treatment.

  6. The reproductive toxicity on the rotifer Brachionus plicatilis induced by BDE-47 and studies on the effective mechanism based on antioxidant defense system changes.

    PubMed

    Wang, Hong; Tang, Xuexi; Sha, Jingjing; Chen, Hongmei; Sun, Tianli; Wang, You

    2015-09-01

    2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), a low-brominated Tetra-BDE that is widely distributed in the marine ecosystem, was selected to investigate the reproductive toxicity on the rotifer, Brachionus plicatilis, and the possible mechanism based on antioxidant defense system changes were studied. The results showed the following: (1) A low concentration of BDE-47 had a slight effect on the egg production of individual females and the egg production rate (EPR) of the population. In fact, BDE-47 exerted reproductive inhibition effects in a time- and concentration-dependent manner. The obtained life tables indicated that BDE-47 at a high concentration prolonged the generation time, whereas low and moderate concentrations of BDE-47 had the opposite effects. BDE-47 at a medium concentration significantly decreased the life expectancy and net reproductive rate (P<0.05). Additionally, a high concentration of BDE-47 markedly decreased the net reproductive rate and intrinsic increase rate (P<0.05). The ultra-structure of the ovary showed that BDE-47 severely damaged the ovary. (2) BDE-47 stress elevated the ROS level in B. plicatilis. The GST activity was induced significantly by the low concentration of BDE-47 and inhibited by the highest concentration tested. The GPx activity and GSH content were significant decreased in all the tested groups, and GR activity was induced. GST and GSH appeared to be sensitive to oxidative stress, and all of the glutathione-related enzymes were found to play an important role in maintaining the antioxidant/pro-oxidant balance based on Pearson's correlation analysis. The results indicated that BDE-47 causes reproductive toxicity in B. plicatilis and that the ROS-mediated pathway is responsible for the observed toxicity.

  7. A teleostan homolog of catalase from black rockfish (Sebastes schlegelii): insights into functional roles in host antioxidant defense and expressional responses to septic conditions.

    PubMed

    Elvitigala, Don Anushka Sandaruwan; Priyathilaka, Thanthrige Thiunuwan; Whang, Ilson; Nam, Bo-Hye; Lee, Jehee

    2015-05-01

    Antioxidative defense renders a significant protection against environmental stress in organisms and maintains the correct redox balance in cells, thereby supporting proper immune function. Catalase is an indispensable antioxidant in organisms that detoxifies hydrogen peroxides produced in cellular environments. In this study, we sought to molecularly characterize a homolog of catalase (RfCat), identified from black rockfish (Sebastes schlegelii). RfCat consists of a 1581 bp coding region for a protein of 527 amino acids, with a predicted molecular weight of 60 kD. The protein sequence of RfCat harbored similar domain architecture to known catalases, containing a proximal active site signature and proximal heme ligand signature, and further sharing prominent homology with its teleostan counterparts. As affirmed by multiple sequence alignments, most of the functionally important residues were well conserved in RfCat. Furthermore, our phylogenetic analysis indicates its common vertebrate ancestral origin and a close evolutionary relationship with teleostan catalases. Recombinantly expressed RfCat demonstrated prominent peroxidase activity that varied with different substrate and protein concentrations, and protected against DNA damage. RfCat mRNA was ubiquitously expressed among different tissues examined, as detected by qPCR. In addition, RfCat mRNA expression was modulated in response to pathogenic stress elicited by Streptococcus iniae and poly I:C in blood and spleen tissues. Collectively, our findings indicate that RfCat may play an indispensable role in host response to oxidative stress and maintain a correct redox balance after a pathogen invasion.

  8. Withania somnifera (Ashwagandha) attenuates antioxidant defense in aged spinal cord and inhibits copper induced lipid peroxidation and protein oxidative modifications.

    PubMed

    Gupta, Sanjeev K; Dua, Anita; Vohra, Bhupinder P S

    2003-01-01

    Withania somnifera is classified in Ayurveda, the ancient Indian system of medicine, as a rasayana, a group of plant-derived drugs which promote physical and mental health, augment resistance of the body against disease and diverse adverse environmental factors, revitalize the body in debilitated conditions and increase longevity. We investigated the effects of Withania somnifera on copper-induced lipid peroxidation and antioxidant enzymes in aging spinal cord of Wistar rats. The activity of glutathione peroxidase (GPx) decreased significantly in the spinal cord from adult to aged mice. Treatment with Withania somnifera successfully attenuated GPx activity and inhibited lipid peroxidation in a dose dependent manner. Withania somnifera inhibited both the lipid peroxidation and protein oxidative modification induced by copper. These effects were similar to those of superoxide dismutase and mannitol. The results indicate the therapeutic potential of Withania somnifera in aging and copper-induced pathophysiological conditions.

  9. Cytokinin oxidase/dehydrogenase overexpression modifies antioxidant defense against heat, drought and their combination in Nicotiana tabacum plants.

    PubMed

    Lubovská, Zuzana; Dobrá, Jana; Storchová, Helena; Wilhelmová, Naďa; Vanková, Radomíra

    2014-11-01

    Cytokinins (CKs) as well as the antioxidant enzyme system (AES) play important roles in plant stress responses. The expression and activity of antioxidant enzymes (AE) were determined in drought, heat and combination of both stresses, comparing the response of tobacco plants overexpressing the main cytokinin degrading enzyme, cytokinin oxidase/dehydrogenase, under the control of root-specific WRKY6 promoter (W6:CKX1 plants) or constitutive promoter (35S:CKX1 plants) and the corresponding wild-type (WT). Expression levels as well as activities of cytosolic ascorbate peroxidase, catalase 3, and cytosolic superoxide dismutase were low under optimal conditions and increased after heat and combined stress in all genotypes. Unlike catalase 3, two other peroxisomal enzymes, catalase 1 and catalase 2, were transcribed extensively under control conditions. Heat stress, in contrast to drought or combined stress, increased catalase 1 and reduced catalase 2 expression in WT and W6:CKX1 plants. In 35S:CKX1, catalase 1 expression was enhanced by heat or drought, but not under combined stress conditions. Mitochondrial superoxide dismutase expression was generally higher in 35S:CKX1 plants than in WT. Genes encoding for chloroplastic AEs, stromatal ascorbate peroxidase, thylakoidal ascorbate peroxidase and chloroplastic superoxide dismutase, were strongly transcribed under control conditions. All stresses down-regulated their expression in WT and W6:CKX1, whereas more stress-tolerant 35S:CKX1 plants maintained high expression during drought and heat. The achieved data show that the effect of down-regulation of CK levels on AES may be mediated by altered habit, resulting in improved stress tolerance, which is associated with diminished stress impact on photosynthesis, and changes in source/sink relations.

  10. Crocus sativus L. (saffron) attenuates isoproterenol-induced myocardial injury via preserving cardiac functions and strengthening antioxidant defense system.

    PubMed

    Sachdeva, Jaspreet; Tanwar, Vineeta; Golechha, Mahaveer; Siddiqui, Khalid M; Nag, Tapas C; Ray, Ruma; Kumari, Santosh; Arya, Dharamvir S

    2012-09-01

    Saffron (dried stigmas of Crocus sativus L.), a naturally derived plant product, has long been used as a traditional ancient medicine against various human diseases. The aim of the series of experiments was to systematically determine whether saffron exerts cardioprotection in isoproterenol-induced myocardial damage. Male Wistar rats (150-175 g) were divided into five groups: control, isoproterenol (ISO) and three saffron (200, 400 and 800 mg/kg) treatment groups. Aqueous extract of saffron or vehicle was administered orally to rats for four weeks. On days 28 and 29, the animals in ISO and saffron treatment groups were administered ISO (85 mg/kg, s.c.) at an interval of 24 h. On day 30, after recording hemodynamics and left ventricular functions, animals were sacrificed for biochemical, histopathological and electromicroscopical examinations. Isoproterenol challenged animals showed depressed hemodynamics and left ventricular functions as evident by decreased left ventricular rate of peak positive and negative pressure change and elevated left ventricular end-diastolic pressure. Structural and ultrastructural studies further confirmed the damage which was reconfirmed by increased thiobarbituric acid reactive substances (p<0.001) and decreased creatine kinase-MB and lactate dehydrogenase (p<0.001). In addition, significant reduction in superoxide dismutase and catalase (p<0.001) was observed in ISO group. Our results suggested that saffron at all the doses exerted significant cardioprotective effect by preserving hemodynamics and left ventricular functions, maintaining structural integrity and augmenting antioxidant status. Among the different doses used, saffron at 400mg/kg dose exhibited maximum protective effects which could be due to maintenance of the redox status of the cell reinforcing its role as an antioxidant.

  11. Effect of treadmill exercise and Ferula gummosa on myocardial HSP72, vascular function, and antioxidant defenses in spontaneously hypertensive rats.

    PubMed

    Gholitabar, Samira; Roshan, Valiollah Dabidi

    2013-01-01

    This study evaluates the effect of treadmill exercise and Ferula gummosa (FG) on heat shock protein (HSP72), biomarkers related to vascular function, and oxidant/antioxidant system in the heart tissue of spontaneously hypertensive rats treated with N(ω)-nitro-L-arginine-methyl ester (L-NAME). Fifty adult male Wistar rats are randomly classified into five groups: treadmill exercise, FG, combination of treadmill exercise + FG, L-NAME, and saline. Treadmill exercise was performed between 25 and 64 minutes at the speed of 15-22 m per minute for 8 weeks and five sessions a week. The FG will be fed through gavage with 90 mg/kg dosage. Hypertension was induced by l-NAME (10 mg/kg) for 8 weeks and six sessions a week. Administration of L-NAME for 8 weeks caused significant increase in HSP72, angiotensin-converting enzyme (ACE), and protein carbonyl (PC), and significant decrease in glutathione peroxidase (GPx) and nitric oxide (NO) level, when compared with the saline group. In contrast, both treadmill exercise and/or FG protocols, in particular, the combined protocol, led to the improvement in HSP72 and balance in oxidant/antioxidant process and inhibited vascular dysfunction, when compared with the L-NAME group. Moreover, no significant differences were detected in the HSP72 level between rats in the treadmill exercise and FG groups. These results provide a rationale for an inhibitory role and a cardioprotective effect of lifestyle related to the health in the attenuation of hypertension-induced cardiotoxicity.

  12. [Antioxidant defense system state in blood plasma and heart muscle of rats under the influence of histamine and sodium hypochlorite].

    PubMed

    Bishko, O I; Harasym, N P; Sanahurs'kyĭ, D I

    2014-01-01

    There is a wide spectrum of antihistamine drugs in the pharmaceutical market, however all these chemical preparations cause side effects. Therefore, new alternative ways for histamine detoxication are to be found. For this aim in our experiment sodium hypochlorite was used because its solution possesses strong oxidizing properties. The influence of histamine and sodium hypochlorite on the antioxidant defence system state of blood plasma and cardiac muscle in rats has been researched. It was shown, that the investigated factors result in the disruption of the antioxidant system. It was found that histamine injection in concentration of 1 and 8 μg/kg in plasma leads to the increase of superoxide dismutase activity during all the experiment. When studying enzymes, that catalyze hydroperoxides and H2O2 decomposition it was shown that under the influence of histamine in a dose 1 μg/kg, the glutathione peroxidase activity increased on the 1st day of the experiment. However, on the 7th day of the experiment the increase of both glutathione peroxidase and catalase activity was fixed. The deviation in superoxide dismutase function in rats plasma under the action of sodium hypochlorite has been established. The activity of enzymes that decompose H2O2 and hydroperoxides were inhibited. Under the influence of histamine in the heart tissues we have stated the disturbance of superoxide dismutase work and increase ofcatalase activity and decrease of glutathione peroxidase activity. The influence of sodium hypochlorite on the myocardium of intact animals as well as joint influence of sodium hypochlorite and histamine result in the increase of superoxide dismutase and catalase activity and lead to the considerable decline of activity of glutathione peroxidase.

  13. Metabolism and antioxidant defense in the larval chironomid Tanytarsus minutipalpus: adjustments to diel variations in the extreme conditions of Lake Magadi

    PubMed Central

    Wood, Chris M.; Bergman, Harold L.; Johannsson, Ora E.; Laurent, Pierre; Chevalier, Claudine; Kisipan, Mosiany L.; Kavembe, Geraldine D.; Papah, Michael B.; Brix, Kevin V.; De Boeck, Gudrun; Maina, John N.; Ojoo, Rodi O.; Bianchini, Adalto

    2017-01-01

    ABSTRACT Insect larvae are reported to be a major component of the simple but highly productive trophic web found in Lake Magadi (Kenya, Africa), which is considered to be one of the most extreme aquatic environments on Earth. Previous studies show that fish must display biochemical and physiological adjustments to thrive under the extreme conditions of the lake. However, information for invertebrates is lacking. In the present study, the occurrence of the larval chironomid Tanytarsus minutipalpus is reported in Lake Magadi for the first time. Additionally, changes in larval metabolism and antioxidant defense correlated with diel variations in the extremely hostile environmental conditions of the lake are described. Wide variations in water temperature (20.2-29.3°C) and dissolved oxygen content (3.2-18.6 mg O2 l−1) were observed at different times of day, without significant change in water pH (10.0±0.03). Temperature and dissolved oxygen were higher at 13:00 h (29.3±0.4°C and 18.6±1.0 mg O2 l−1) and 19:00 h (29.3±0.8°C and 16.2±1.6 mg O2 l−1) and lower at 01:00 h (21.1±0.1°C and 10.7±0.03 mg O2 l−1) and 07:00 h (20.2±0.4°C and 3.2±0.7 mg O2 l−1). Significant and parallel increases in parameters related to metabolism (cholinesterase, glucose, cholesterol, urea, creatinine and hemoglobin) and the antioxidant system (SOD, GPx, GR, GSH and GSSG) were observed in larvae collected at 13:00 h. In contrast, no significant changes were observed in pro-oxidants (ROS and NO), TOSC and oxidative damage parameters (LPO and DNA damage). Therefore, the observed increases in temperature and dissolved O2 content in Lake Magadi were associated with changes in the antioxidant system of T. minutipalpus larvae. Adjustments performed by the chironomid larvae were efficient in maintaining body homeostasis, as well as protecting biomolecules against oxidative damage, so that oxidative stress did not occur. GSH-GSSG and GPx-GR systems appeared to

  14. Metabolism and antioxidant defense in the larval chironomid Tanytarsus minutipalpus: adjustments to diel variations in the extreme conditions of Lake Magadi.

    PubMed

    Bianchini, Lucas F; Wood, Chris M; Bergman, Harold L; Johannsson, Ora E; Laurent, Pierre; Chevalier, Claudine; Kisipan, Mosiany L; Kavembe, Geraldine D; Papah, Michael B; Brix, Kevin V; De Boeck, Gudrun; Maina, John N; Ojoo, Rodi O; Bianchini, Adalto

    2017-01-15

    Insect larvae are reported to be a major component of the simple but highly productive trophic web found in Lake Magadi (Kenya, Africa), which is considered to be one of the most extreme aquatic environments on Earth. Previous studies show that fish must display biochemical and physiological adjustments to thrive under the extreme conditions of the lake. However, information for invertebrates is lacking. In the present study, the occurrence of the larval chironomid Tanytarsus minutipalpus is reported in Lake Magadi for the first time. Additionally, changes in larval metabolism and antioxidant defense correlated with diel variations in the extremely hostile environmental conditions of the lake are described. Wide variations in water temperature (20.2-29.3°C) and dissolved oxygen content (3.2-18.6 mg O2 l(-1)) were observed at different times of day, without significant change in water pH (10.0±0.03). Temperature and dissolved oxygen were higher at 13:00 h (29.3±0.4°C and 18.6±1.0 mg O2 l(-1)) and 19:00 h (29.3±0.8°C and 16.2±1.6 mg O2 l(-1)) and lower at 01:00 h (21.1±0.1°C and 10.7±0.03 mg O2 l(-1)) and 07:00 h (20.2±0.4°C and 3.2±0.7 mg O2 l(-1)). Significant and parallel increases in parameters related to metabolism (cholinesterase, glucose, cholesterol, urea, creatinine and hemoglobin) and the antioxidant system (SOD, GPx, GR, GSH and GSSG) were observed in larvae collected at 13:00 h. In contrast, no significant changes were observed in pro-oxidants (ROS and NO), TOSC and oxidative damage parameters (LPO and DNA damage). Therefore, the observed increases in temperature and dissolved O2 content in Lake Magadi were associated with changes in the antioxidant system of T. minutipalpus larvae. Adjustments performed by the chironomid larvae were efficient in maintaining body homeostasis, as well as protecting biomolecules against oxidative damage, so that oxidative stress did not occur. GSH-GSSG and GPx-GR systems appeared to play an

  15. Role of Trichoderma harzianum in mitigating NaCl stress in Indian mustard (Brassica juncea L) through antioxidative defense system

    PubMed Central

    Ahmad, Parvaiz; Hashem, Abeer; Abd-Allah, Elsayed Fathi; Alqarawi, A. A.; John, Riffat; Egamberdieva, Dilfuza; Gucel, Salih

    2015-01-01

    Salinity stress affected crop production of more than 20% of irrigated land globally. In the present study the effect of different concentrations of NaCl (0, 100, and 200 mM) on growth, physio-biochemical attributes, antioxidant enzymes, oil content, etc. in Brassica juncea and the protective role of Trichoderma harzianum (TH) was investigated. Salinity stress deteriorates growth, physio-biochemical attributes, that ultimately leads to decreased biomass yield in mustard seedlings. Higher concentration of NaCl (200 mM) decreased the plant height by 33.7%, root length by 29.7% and plant dry weight (DW) by 34.5%. On the other hand, supplementation of TH to NaCl treated mustard seedlings showed elevation by 13.8, 11.8, and 16.7% in shoot, root length and plant DW respectively as compared to plants treated with NaCl (200 mM) alone. Oil content was drastically affected by NaCl treatment; however, TH added plants showed enhanced oil percentage from 19.4 to 23.4% in the present study. NaCl also degenerate the pigment content and the maximum drop of 52.0% was recorded in Chl. ‘a’. Enhanced pigment content was observed by the application of TH to NaCl treated plants. Proline content showed increase by NaCl stress and maximum accumulation of 59.12% was recorded at 200 mM NaCl. Further enhancement to 70.37% in proline content was recorded by supplementation of TH. NaCl stress (200 mM) affirms the increase in H2O2 by 69.5% and MDA by 36.5%, but reduction in the accumulation is recorded by addition of TH to mustard seedlings. 200 mM NaCl elevated SOD, POD, APX, GR, GST, GPX, GSH, and GSSG in the present study. Further enhancement was observed by the application of TH to the NaCl fed seedlings. NaCl stress suppresses the uptake of important elements in both roots and shoots, however, addition of TH restored the elemental uptake in the present study. Mustard seedlings treated with NaCl and TH showed restricted Na uptake as compared to seedlings treated with NaCl alone. In

  16. Coenzyme Q10 and fish oil synergistically alleviate aluminum chloride-induced suppression of testicular steroidogenesis and antioxidant defense.

    PubMed

    Mohammad, Nanies Sameeh; Arafa, Manar Hamed; Atteia, Hebatallah Husseini

    2015-01-01

    Aluminum (Al) is an environmental xenobiotic that stimulates free radical generation and hence reproductive toxicity. Coenzyme Q10 (CoQ10) effectively counteracts free radical-induced tissue damage. Omega-3 polyunsaturated fatty acids present in fish oil (FO) exert beneficial effects on reproduction in male animals. This study therefore investigated the effects of both agents on testicular dysfunction induced by aluminum chloride (AlCl3). Fifty male rats were gavaged with either 1% gum acacia (control group) or AlCl3 (34 mg/kg/day) for ten weeks. Concurrently, AlCl3-treated rats received no treatment, CoQ10 (10 mg/kg/day, p.o.), and/or FO (400 mg/kg/day, p.o.) for ten weeks. AlCl3 caused a significant decrease in serum testosterone, luteinizing hormone (LH), and follicular stimulating hormone (FSH), as well as testicular weight, antioxidant enzyme gene expression and activities, reduced glutathione, zinc, adenosine 3',5'-cyclic monophosphate (cAMP) contents, and number of Leydig cells, along with down-regulation of 3beta-hydroxysteroid dehydrogenase (3β-HSD), 17β-HSD, steroidogenic acute regulatory protein (STAR), and cholesterol side-chain cleavage enzyme (P450scc) gene expression. However, testicular Al, malondialdehyde (MDA), and nitric oxide (NO) levels were markedly increased. Treatment with CoQ10 and FO, alone or in combined form led to an improvement in the aforementioned biomarkers. Overall, individual or combined treatment with CoQ10 and FO could ameliorate the toxic effects of AlCl3 on testicular tissues by mechanisms related to their potent antioxidant potential and stimulatory effects on steroidogenic enzymes transcription. CoQ10 seems to be better than FO regarding oxidative and nitrosative stress, Zn deficiency, and Al overload. However, FO showed more pronounced effect than CoQ10 on hormones, steroidogenic markers, and cAMP. A cocktail of both demonstrated greater protective effects on testicular tissues than monotherapy.

  17. Effects of experimentally induced maternal hypothyroidism and hyperthyroidism on the development of rat offspring: II-the developmental pattern of neurons in relation to oxidative stress and antioxidant defense system.

    PubMed

    Ahmed, O M; Ahmed, R G; El-Gareib, A W; El-Bakry, A M; Abd El-Tawab, S M

    2012-10-01

    Excessive concentrations of free radicals in the developing brain may lead to neurons maldevelopment and neurons damage and death. Thyroid hormones (THs) states play an important role in affecting the modulation of oxidative stress and antioxidant defense system. Thus, the objective of this study was to clarify the effect of hypothyroidism and hyperthyroidism in rat dams on the neurons development of different brain regions of their offspring at several postnatal weeks in relation to changes in the oxidative stress and antioxidant defense system. The adult female rats were administered methimazole (MMI) in drinking water (0.02% w/v) from gestation day 1 to lactation day 21 to induce hypothyroidism and exogenous thyroxine (T4) in drinking water (0.002% w/v) beside intragastric incubation of 50--200 T4 μg/kg body weight (b. wt.) to induce hyperthyroidism. In normal female rats, the sera total thyroxine (TT4) and total triiodothyronine (TT3) levels were detectably increased at day 10 post-partum than those at day 10 of pregnancy. Free thyroxine (FT4), free triiodothyronine (FT3), thyrotropin (TSH) and growth hormone (GH) concentrations in normal offspring were elevated at first, second and third postnatal weeks in an age-dependent manner. In hypothyroid group, a marked depression was observed in sera of dam TT3 and TT4 as well as offspring FT3, FT4 and GH, while there was a significant increase in TSH level with the age progress. The reverse pattern to latter state was recorded in hyperthyroid group. Concomitantly, in control offspring, the rate of neuron development in both cerebellar and cerebral cortex was increased in its density and complexity with age progress. This development may depend, largely, on THs state. Both maternal hypothyroidism and hyperthyroidism caused severe growth retardation in neurons of these regions of their offspring from the first to third weeks. Additionally, in normal offspring, seven antioxidant enzymes, four non-enzymatic antioxidants

  18. Mammalian cells exhibit a range of sensitivities to silver nanoparticles that are partially explicable by variations in antioxidant defense and metallothionein expression

    PubMed Central

    Zhang, Haiyuan; Wang, Xiang; Wang, Meiying; Li, Linjiang; Chang, Chong Hyun; Ji, Zhaoxia; Xia, Tian; Nel, Andre E.

    2015-01-01

    While it is well known that there are interspecies differences in Ag sensitivity, we have also observed differences in the cytotoxic responses of mammalian cells to silver nanoparticles (Ag NPs). In order to explore these response outcomes, six cell lines, including epithelial cells (Caco-2, NHBE, RLE-6TN and BEAS-2B) and macrophages (RAW 264.7 and THP-1) of human and rodent origin were exposed to 20 nm citrate- and PVP-coated AgNPs with Au cores as well as 20 nm citrate-coated particles without cores. A MTS assay showed that while Caco-2 and NHBE cells were resistant to particles over a 0.1- 50 μg/mL dose range, RAW 264.7, THP-1, RLE-6TN and BEAS-2B cells were more susceptible. While there were small differences in dissolution rates, there were no major differences in the cytotoxic potential of the different particles. However, we did observe differences in anti-oxidant defense and metallothionein expression among different cell types, which can partially explain differential AgNP sensitivity. So it is important to consider these differences in understanding the potential heterogeneous effects of nano Ag on mammalian biological systems. PMID:25930061

  19. Overexpression of the Maize psbA Gene Enhances Drought Tolerance Through Regulating Antioxidant System, Photosynthetic Capability, and Stress Defense Gene Expression in Tobacco.

    PubMed

    Huo, Yongjin; Wang, Meiping; Wei, Yangyang; Xia, Zongliang

    2015-01-01

    The psbA (encoding D1 protein) plays an important role in protecting photosystem II (PSII) from oxidative damage in higher plants. In our previous study, the role of the psbA from maize (Zea mays. L) in response to SO2 stress was characterized. To date, information about the involvement of the psbA gene in drought response is scarce. Here we found that overexpression (OE) of ZmpsbA showed increased D1 protein abundance and enhanced drought stress tolerance in tobacco. The drought-tolerant phenotypes of the OE lines were accompanied by increases of key antioxidant enzymes SOD, CAT, and POD activities, but decreases of hydrogen peroxide, malondialdehyde, and ion leakage. Further investigation showed that the OE plants had much less reductions than the wild-type in the net photosynthesis rate (Pn), stomatal conductance (Gs), and the maximal photochemical efficiency of PSII (Fv/Fm) during drought stress; indicating that OE of ZmpsbA may alleviate photosynthesis inhibition during drought. qRT-PCR analysis revealed that there was significantly increased expression of NtLEA5, NtERD10C, NtAREB, and NtCDPK2 in ZmpsbA-OE lines. Together, our results indicate that ZmpsbA improves drought tolerance in tobacco possibly by alleviating photosynthesis reduction, reducing reactive oxygen species accumulation and membrane damage, and modulating stress defense gene expression. ZmpsbA could be exploited for engineering drought-tolerant plants in molecular breeding of crops.

  20. Implications of mycosporine-like amino acid and antioxidant defenses in UV-B radiation tolerance for the algae species Ptercladiella capillacea and Gelidium amansii.

    PubMed

    Lee, Tse-Min; Shiu, Chia-Tai

    2009-02-01

    Ultraviolet-B (UV-B) radiation (0.5, 1.0, 1.5, and 3.0Wm(-2)) induced higher H(2)O(2) production and lipid peroxidation in alga Gelidium amansii inhabiting in lower subtidal regions than upper subtidal alga Ptercladiella capillacea. Compared to G. amansii, mycosporine-like amino acid (MAA) concentration in P. capillacea was higher and can be increased by 0.5-1.0Wm(-2) UV-B, while carotenoid concentration was lower but also increased by 1.5-3.0Wm(-2) UV-B. UV-B increased ascorbate concentration, but to a higher degree in P. capillacea. UV-B decreased glutathione concentration, but to a higher degree in G. amansii. UV-B increased ascorbate peroxidase (APX) and glutathione reductase (GR) activities in P.capillacea but decreased them in G. amansii. UV-B increased superoxide dismutase and catalase activities, but to a higher degree in G. amansii. So, G. amansii suffered greater oxidative stress from UV-B radiation. P. capillacea can effectively reduce UV-B sensitivity by increasing sunscreen ability and antioxidant defense capacity.

  1. Resistance to the Beneficial Metabolic Effects and Hepatic Antioxidant Defense Actions of Fibroblast Growth Factor 21 Treatment in Growth Hormone-Overexpressing Transgenic Mice

    PubMed Central

    Boparai, Ravneet K.; Arum, Oge; Miquet, Johanna G.; Masternak, Michal M.; Khardori, Romesh K.

    2015-01-01

    Fibroblast growth factor 21 (FGF21) modulates a diverse range of biological functions, including glucose and lipid metabolism, adaptive starvation response, and energy homeostasis, but with limited mechanistic insight. FGF21 treatment has been shown to inhibit hepatic growth hormone (GH) intracellular signaling. To evaluate GH axis involvement in FGF21 actions, transgenic mice overexpressing bovine GH were used. Expectedly, in response to FGF21 treatment control littermates showed metabolic improvements whereas GH transgenic mice resisted most of the beneficial effects of FGF21, except an attenuation of the innate hyperinsulinemia. Since FGF21 is believed to exert its effects mostly at the transcriptional level, we analyzed and observed significant upregulation in expression of various genes involved in carbohydrate and lipid metabolism, energy homeostasis, and antioxidant defense in FGF21-treated controls, but not in GH transgenics. The resistance of GH transgenic mice to FGF21-induced changes underlines the necessity of normal GH signaling for the beneficial effects of FGF21. PMID:26089880

  2. Changes in Antioxidant Defense Capability and Lipid Profile after 12-Week Low- Intensity Continuous Training in Both Cigarette and Hookah Smokers: A Follow-Up Study

    PubMed Central

    Koubaa, Abdessalem; Triki, Moez; Trabelsi, Hajer; Masmoudi, Liwa; Sahnoun, Zouhair; Hakim, Ahmed

    2015-01-01

    To examine the impact of low-intensity continuous training program on antioxidant defense capability and lipid profile in male cigarette or hookah smokers. Forty-three male adults participated in a 12-week continuous training program at an intensity of 40% of VO2max. All subjects were subjected to anthropometric, physical and biochemical tests before and after the training program. The increase of Glutathione reductase (GR) and Superoxide dismutase (SOD) is significant only for cigarette smokers (CS) and hookah smokers (HS) groups. The Malondialdehyde (MDA) decrease and α-tocopherol increase are significant only for HS group. GPx was increased in NS, CS and HS by 2.6% (p< 0.01), 2% (p< 0.05) and 1.7% (p< 0.05) respectively. Likewise, significant improvements of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and TC / HDL-C ratio were observed in three groups. En contrast no significant changes were recorded in triglycerides (TG). Also, significant reduction of total cholesterol (TC) for CS group (p< 0.01) and HS groups (p< 0.05). This continuous training program appears to have an important role in lipid levels improving and oxidative stress attenuation. PMID:26121249

  3. Spontaneous ultraweak photon emission imaging of oxidative metabolic processes in human skin: effect of molecular oxygen and antioxidant defense system

    NASA Astrophysics Data System (ADS)

    Rastogi, Anshu; Pospíšil, Pavel

    2011-09-01

    All living organisms emit spontaneous ultraweak photon emission as a result of cellular metabolic processes. In this study, the involvement of reactive oxygen species (ROS) formed as the byproduct of oxidative metabolic processes in spontaneous ultraweak photon emission was studied in human hand skin. The effect of molecular oxygen and ROS scavengers on spontaneous ultraweak photon emission from human skin was monitored using a highly sensitive photomultiplier tube and charged coupled device camera. When spontaneous ultraweak photon emission was measured under anaerobic conditions, the photon emission was decreased, whereas under hyperaerobic condition the enhancement in photon emission was observed. Spontaneous ultraweak photon emission measured after topical application of glutathione, α-tocopherol, ascorbate, and coenzyme Q10 was observed to be decreased. These results reveal that ROS formed during the cellular metabolic processes in the epidermal cells play a significant role in the spontaneous ultraweak photon emission. It is proposed that spontaneous ultraweak photon emission can be used as a noninvasive tool for the temporal and spatial monitoring of the oxidative metabolic processes and intrinsic antioxidant system in human skin.

  4. Gestational Diabetes Mellitus Impairs Nrf2-Mediated Adaptive Antioxidant Defenses and Redox Signaling in Fetal Endothelial Cells In Utero

    PubMed Central

    Cheng, Xinghua; Chapple, Sarah J.; Patel, Bijal; Puszyk, William; Sugden, David; Yin, Xiaoke; Mayr, Manuel; Siow, Richard C.M.; Mann, Giovanni E.

    2013-01-01

    In utero exposure to gestational diabetes mellitus (GDM) is associated with an increased risk of type 2 diabetes and cardiovascular disease in later life, yet the underlying mechanisms remain to be elucidated. We examined the effects of GDM on the proteome, redox status, and nuclear factor erythroid 2–related factor 2 (Nrf2)-mediated antioxidant gene expression in human fetal endothelial cells. Proteomic analysis revealed that proteins involved in redox homeostasis were significantly altered in GDM and associated with increased mitochondrial superoxide generation, protein oxidation, DNA damage, and diminished glutathione (GSH) synthesis. In GDM cells, the lipid peroxidation product 4-hydroxynonenal (HNE) failed to induce nuclear Nrf2 accumulation and mRNA and/or protein expression of Nrf2 and its target genes NAD(P)H:quinone oxidoreductase 1 (NQO1), Bach1, cystine/glutamate transporter, and glutamate cysteine ligase. Although methylation of CpG islands in Nrf2 or NQO1 promoters was unaltered by GDM, decreased DJ-1 and increased phosphorylated glycogen synthase kinase 3β levels may account for impaired Nrf2 signaling. HNE-induced increases in GSH and NQO1 levels were abrogated by Nrf2 small interfering RNA in normal cells, and overexpression of Nrf2 in GDM cells partially restored NQO1 induction. Dysregulation of Nrf2 in fetal endothelium may contribute to the increased risk of type 2 diabetes and cardiovascular disease in offspring. PMID:23974919

  5. Seasonal and ontogenetic changes modulate oxygen consumption and antioxidant defenses in the cutlassfish Trichiurus lepturus (Pisces, Trichiuridae).

    PubMed

    Filho, Danilo Wilhelm; Fraga, César G; Boveris, Alberto

    2017-03-24

    Several oxidative stress markers and liver oxygen consumption were measured in different tissues of the marine fish Trichiurus lepturus in late summer and late winter, as well as in juveniles and adult females. Oxygen consumption in liver, superoxide dismutase (SOD) and catalase (CAT) activity in liver, red cells, lens and roe, vitamin E, ubiquinol10, β-carotene in liver, red cells, and roe, as well as contents of reduced glutathione (GSH) and lipoperoxidation (TBARS) in red cells were evaluated. Regarding ontogeny, compared to adult fish, juveniles showed significant higher SOD activity in liver and lens, as well as higher liver contents of vitamin E. In contrast, adult females showed higher contents of vitamin E in roe, ubiquinol10 in liver and roe, and higher GSH levels in red cells, while the other markers remained unchanged. Regarding seasonal changes, no differences were detected in adult females for liver CAT and ubiquinol10, CAT in roe, vitamin E in roe and in red cells, liver and red cell ubiquinol10, and in GSH in red cells. However, and coinciding with the spawning period of late summer, liver oxygen consumption, SOD and CAT activity and ubiquinol10 contents in roe and SOD activity in red cells, and red cell TBARS contents were higher compared to late winter. These temporal antioxidant adjustments of Trichiurus lepturus seem to be parallel to the higher oxygen consumption typical of juvenile forms and also to the intense spawning and foraging activities of adult females in late summer.

  6. Effects of anthracene on filtration rates, antioxidant defense system, and redox proteomics in the Mediterranean clam Ruditapes decussatus (Mollusca: Bivalvia).

    PubMed

    Sellami, Badreddine; Khazri, Abdelhafidh; Louati, Héla; Dellali, Mohamed; Driss, Mouhamed Ridha; Aïssa, Patricia; Mahmoudi, Ezzeddine; Hamouda, Beyrem; Coelho, Ana Varela; Sheehan, David

    2015-07-01

    This study aimed at analyzing the impact of a toxic polyaromatic hydrocarbon (PAH), anthracene (ANT), on Ruditapes decussatus collected from a Tunisian coastal lagoon (Bizerte Lagoon). Filtration rates, several antioxidant enzymes--superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione transferase (GST)--as well as indices of protein oxidation status were determined in various tissues of this bivalve. Specimens were exposed to 100 μg/L of ANT for 2 days. ANT levels were evaluated using HPLC and were detected in the gill and digestive gland at different amounts. ANT exposure altered the behavior of bivalves by changing the siphon movement and decreasing filtration rate significantly. The enzymatic results indicated that ANT exposure affected the oxidative stress status of the gills of R. decussatus. In addition, modification of proteins was detected in the gills using redox proteomics after ANT treatment. Three protein spots were successfully identified by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-MS). These proteins can be roughly related to muscle contraction function. In contrast, no significant modification of enzymatic and protein responses was detected in the digestive gland after ANT treatment. These data demonstrate that combined behavioral and biochemical analyses are a powerful tool to provide valuable insights into possible mechanisms of toxicity of anthracene in R. decussatus. Additionally, the results highlight the potential of the gill as a valuable candidate for investigating PAH toxicity.

  7. New insight into the effects of lead modulation on antioxidant defense mechanism and trace element concentration in rat bone.

    PubMed

    Payal, Bhardwaj; Kaur, Harkiran Preet; Rai, Durg Vijay

    2009-03-01

    Risks of heavy metals-induced severe bone disorders generate interest to their toxicity. The present study was undertaken to monitor the biochemical and antioxidant status of bone of 30 and 80 days old male Wistar rats exposed to 5 week lead treatment. At the end of study, the rats were sacrificed, their long bone i.e. femur were excised, cleaned of soft tissue, minced and homogenized. Nucleic acid content, alkaline phosphatase, lipid peroxidation, catalase, glutathione S-transferase and superoxide dismutase were determined in bone. In both groups of treated animals lead treatment increased the production of malondialdehyde, while reducing activities of catalase, glutathione S-transferase and superoxide dismutase, indicating that it causes oxidative stress. Parallely with these effects lead significantly reduced the nucleic acid content and the activity of alkaline phosphatase, considered as biomarkers of osteoblast's function, conditions and development of bones. Moreover the concentrations of copper, zinc, iron and sodium were reduced in the excised bones. The present study indicates that the lead induced bone toxicity and its deteriorated development is the consequence of a primary oxidative stress. Our results may be helpful in understanding the modulation of biochemical parameters under lead toxicity.

  8. Sasa borealis Extract Efficiently Enhanced Swimming Capacity by Improving Energy Metabolism and the Antioxidant Defense System in Mice.

    PubMed

    You, Yanghee; Kim, Kyungmi; Yoon, Ho-Geun; Choi, Kyung-Chul; Lee, Yoo-Hyun; Lee, Jeongmin; Jun, Woojin

    2015-01-01

    This study was conducted to determine the effects of 50% ethanolic extract from Sasa borealis leaves (SBE) on swimming capacity and oxidative metabolism in mice. The mice were divided into 2 groups with similar swimming times and body weights; Ex-Control and Ex-SBE were orally administered with distilled water and 250 mg/kg body weight/d of SBE. Exhaustive swimming times were prolonged by 1.5-fold in the Ex-SBE group compared to the Ex-Control. The Ex-SBE group displayed lower lactate and higher non-esterified fatty acid levels 15 min after swimming and the hepatic and muscle glycogen levels were significantly higher than that in the Ex-Control. SBE potentially enhanced mRNA expression of citrate synthase (CS), carnitine palmitoyltransferase (CPT-1), and β-hydroxyacyl coenzyme A dehydrogenase (β-HAD) in skeletal muscle. The activities and mRNA expression of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) were elevated in the Ex-SBE compared with the Ex-Control after exhaustive swimming. These results suggest that SBE might be used as an effective agent to enhance swimming capacity by utilization of energy substrates and might ameliorate physical exhaustion by facilitating energy-generating metabolic genes and enhancing endogenous antioxidants.

  9. Surface modification by argon plasma treatment improves antioxidant defense ability of CHO-k1 cells on titanium surfaces.

    PubMed

    de Queiroz, Jana Dara Freires; Leal, Angélica Maria de Sousa; Terada, Maysa; Agnez-Lima, Lucymara Fassarela; Costa, Isolda; Pinto, Nadja Cristhina de Souza; de Medeiros, Silvia Regina Batistuzzo

    2014-04-01

    Titanium is one of the most used materials in implants and changes in its surface can modify the cellular functional response to better implant fixation. An argon plasma treatment generates a surface with improved mechanical proprieties without modifying its chemical composition. Oxidative stress induced by biomaterials is considered one of the major causes of implant failure and studies in this field are fundamental to evaluate the biocompatibility of a new material. Therefore, in this work, induction of oxidative stress by titanium surfaces subjected to plasma treatment (PTTS) was evaluated. The viability of CHO-k1 cells was higher on PTTS discs. Cells grown on titanium surfaces are subjected to intracellular oxidative stress. Titanium discs subjected to the plasma treatment induced less oxidative stress than the untreated ones, which resulted in improved cellular survival. These were associated with improved cellular antioxidant response in Plasma Treated Titanium Surface (PTTS). Furthermore, a decrease in protein and DNA oxidative damage was observed on cells grown on the roughed surface when compared to the smooth one. In conclusion, our data suggest that the treatment of titanium with argon plasma may improve its biocompatible, thus improving its performance as implants or as a scaffold in tissue engineering.

  10. Alpha-tocopherol-dependent salt tolerance is more related with auxin synthesis rather than enhancement antioxidant defense in soybean roots.

    PubMed

    Sereflioglu, Seda; Dinler, Burcu Seckin; Tasci, Eda

    2017-03-01

    In this paper, we describe the alleviated effects of alpha-tocopherol (α-T) on oxidative damage and its possible role as a signal transmitter in plants during salt stress. The results show that exogenously applied α-T under salt stress increased root length and weight, but reduced hydrogen peroxide (H2O2), superoxide anion radical (O2(.)-) and malondialdehyde (MDA) content in soybean roots. The proline content was reduced by α-T treatment. Interestingly, endogenous auxin (IAA) level was significantly increased after α-T application as compared to salt stress alone. Moreover, α-T reduced significantly superoxide dismutase (SOD) enzyme and isoenzyme activity but upregulated peroxidase (POX) 2, 3 and glutathione-s-transferase (GST) 1, 3 isoenzyme expression. However, ascorbate peroxidase (APX) enzyme activity was not affected at all. Consequently, the results show that α-T serves as a signal molecule under salinity from leaves to roots by increasing remarkably endogenous IAA levels and increasing partially antioxidant activity in roots.

  11. Salmonella proteomics under oxidative stress reveals coordinated regulation of antioxidant defense with iron metabolism and bacterial virulence.

    PubMed

    Fu, Jiaqi; Qi, Linlu; Hu, Mo; Liu, Yanhua; Yu, Kaiwen; Liu, Qian; Liu, Xiaoyun

    2017-03-22

    Salmonella Typhimurium is a bacterial pathogen that can cause widespread gastroenteritis. Salmonella encounters reactive oxygen species both under free-living conditions and within their mammalian host during infection. To study its response to oxidative stress, we performed the first large-scale proteomic profiling of Salmonella upon exposure to H2O2. Among 1600 detected proteins, 83 proteins showed significantly altered abundance. Interestingly, only a subset of known antioxidants was induced, likely due to distinct regulatory mechanisms. In addition, we found elevation of several Salmonella acquired phage products with potential contribution to DNA repair under oxidative stress. Furthermore, we observed robust induction of iron-uptake systems and disruption of these pathways led to bacterial survival defects under H2O2 challenge. Importantly, this work is the first to report that oxidative stress severely repressed the Salmonella type III secretion system (T3SS), reducing its virulence. Biological significance Salmonella, a Gram-negative bacterial pathogen, encounters reactive oxygen species (ROS) both endogenously and exogenously. To better understand its response to oxidative stress, we performed the first large-scale profiling of Salmonella protein expression upon H2O2 treatment. Among 1600 quantified proteins, the abundance of 116 proteins was altered significantly. Notably, iron acquisition systems were induced to promote bacterial survival under oxidative stress. Furthermore, we are the first to report that oxidative stress severely repressed Salmonella type III secretion system and hence reduced its virulence. We believe that these findings will not only help us better understand the molecular mechanisms that Salmonella has evolved to counteract ROS but also the global impact of oxidative stress on bacterial physiology.

  12. Sulfur mediated reduction of arsenic toxicity involves efficient thiol metabolism and the antioxidant defense system in rice.

    PubMed

    Dixit, Garima; Singh, Amit Pal; Kumar, Amit; Singh, Pradyumna Kumar; Kumar, Smita; Dwivedi, Sanjay; Trivedi, Prabodh Kumar; Pandey, Vivek; Norton, Gareth John; Dhankher, Om Parkash; Tripathi, Rudra Deo

    2015-11-15

    Arsenic (As) contamination is a global issue, with South Asia and South East Asia being worst affected. Rice is major crop in these regions and can potentially pose serious health risks due to its known As accumulation potential. Sulfur (S) is an essential macronutrient and a vital element to combat As toxicity. The aim of this study was to investigate the role of S with regards to As toxicity in rice under different S regimes. To achieve this aim, plants were stressed with AsIII and AsV under three different S conditions (low sulfur (0.5mM), normal sulfur (3.5mM) and high sulfur (5.0mM)). High S treatment resulted in increased root As accumulation, likely due to As complexation through enhanced synthesis of thiolic ligands, such as non-protein thiols and phytochelatins, which restricted As translocation to the shoots. Enzymes of S assimilatory pathways and downstream thiolic metabolites were up-regulated with increased S supplementation; however, to maintain optimum concentrations of S, transcript levels of sulfate transporters were down-regulated at high S concentration. Oxidative stress generated due to As was counterbalanced in the high S treatment by reducing hydrogen peroxide concentration and enhancing antioxidant enzyme activities. The high S concentration resulted in reduced transcript levels of Lsi2 (a known transporter of As). This reduction in Lsi2 expression level is a probable reason for low shoot As accumulation, which has potential implications in reducing the risk of As in the food chain.

  13. [Toxicological evaluation of colloidal nano-sized silver stabilized polyvinylpyrrolidone. III. Enzymological, biochemical markers, state of antioxidant defense system].

    PubMed

    Gmoshinsky, I V; Shipelin, V A; Vorozhko, I V; Sentsova, T B; Soto, S Kh; Avren'eva, L I; Guseva, G V; Kravchenko, L V; Khotimchenko, S A; Tutelyan, V A

    2016-01-01

    Nanosized colloidal silver (NCS) with primary nanoparticles (NPs) size in the range of 10-80 nm in aqueous suspension was administered to rats with initial weight 80±10 gfor the first 30 day intragastrically and for lasting 62 days with the diet consumed in doses of 0.1; 1.0 and 10 mg/kg of body weight b.w) per day based on silver (Ag). The control animals received deionized water and carrier of NPs - aqueous solution of stabilizer polyvinylpyrrolidone. Activity (Vmax) was determined in liver of microsomal mixed function monooxygenase isoforms CYP 1A1, 1A2 and 2B1 against their specific substrates, the activity of liver conjugating enzymes (glutathione-S-transferase and UDP-glucuronosyltransferase) in the microsomal fraction and a cytosol, and the overall and non-sedimentable activities of lysosomal hydrolases. In blood plasma there were evaluated malonic dialdehyde, PUFA diene conjugates, in erythrocytes - the activity of antioxidant enzymes. A set of standard biochemical indicators of blood serum was also determined. The studies revealed changes in a number of molecular markers of toxic action. Among them - the increase in the activity of key enzymes I and II stages of detoxification of xenobiotics, indicating its functional overvoltage; reducing the activity of glutathione peroxidase (GP), the total arylsulfatase A and B, β-galactosidase (in the absence of changes in their non-sedimentable activity), levels of uric acid, increased alkaline phosphatase activity. These changes occurred mainly at the dose Ag of 10 mg/kg b.w., except for the GP to which the threshold dose was 1 mg/kg b.w. No significant changes in the studied markers in a dose Ag 0,1 mg/kg b.w. were identified. Possible mechanisms of the toxic action of silver NPs are discussed.

  14. Influence of dietary copper concentrations on growth performance, serum lipid profiles, antioxidant defenses, and fur quality in growing-furring male blue foxes (Vulpes lagopus).

    PubMed

    Liu, Z; Wu, X; Zhang, T; Cui, H; Guo, J; Guo, Q; Gao, X; Yang, F

    2016-03-01

    A 75-d experiment was conducted to evaluate the influence of dietary Cu concentrations on growth performance, serum lipid profiles, antioxidant defenses, and fur quality in growing-furring male blue foxes. Seventy-five male blue foxes (5.78 ± 0.09 kg BW) were selected and randomly allocated to 1 of the following 5 dietary treatments: 1) control (basal diet without supplemental Cu; 7.78 mg Cu/kg), 2) 12.22 mg/kg supplemental Cu (Cu20), 3) 32.22 mg/kg supplemental Cu, 4) 72.22 mg/kg supplemental Cu (Cu80), and 5) 152.22 mg/kg supplemental Cu (Cu160). A dry feed that consisted of animal meals, soybean meal, extruded corn, and soybean oil was used as the basal diet and Cu was supplemented as reagent grade CuSO∙5HO. The results showed that Cu supplementation increased the ADG ( < 0.05) and fat digestibility ( < 0.01) and tended to improve G:F ( = 0.09). The ADFI, however, was not affected by dietary Cu ( > 0.10). Additionally, Cu supplementation linearly increased the concentration of fecal Cu, liver Cu, serum total protein, and albumin ( < 0.01). Foxes in the Cu160 group had higher serum Cu concentration than those in the control and Cu20 groups ( < 0.05). The concentration of serum cholesterol decreased with dietary Cu supplementation ( < 0.05). Serum high-density lipoprotein, on the contrary, tended to increase with Cu supplementation ( = 0.09). Copper supplementation increased the activity of glutathione peroxidase ( < 0.05) and tended to increase the activity of serum ceruloplasmin ( = 0.07). For fur quality, skin length in the Cu80 group was greater than that in the control and Cu20 groups. In addition, hair color tended to deepen with the increasing of dietary Cu concentrations ( = 0.08). In conclusion, this study demonstrates that Cu supplementation can promote growth and increase fat digestibility and fur length. Additionally, dietary Cu supplementation can enhance antioxidant capacity and reduce serum cholesterol in growing-furring blue foxes.

  15. Spray-dried plasma promotes growth, modulates the activity of antioxidant defenses, and enhances the immune status of gilthead sea bream (Sparus aurata) fingerlings.

    PubMed

    Gisbert, E; Skalli, A; Campbell, J; Solovyev, M M; Rodríguez, C; Dias, J; Polo, J

    2015-01-01

    Terrestrial animal byproduct meals, including nonruminant blood meal and blood products, represent the largest and largely untapped safe source of animal protein available within the international market for the aquafeed industry. Spray-dried blood and spray-dried plasma (SDP) proteins have long been recognized as high-quality feed ingredients for farmed animals. In this study, we evaluated the inclusion of SDP from porcine blood (SDPP) in growing diets for gilthead sea bream. Three isonitrogenous (CP = 51.2%) and isolipidic (fat = 12.4%) diets manufactured by cold extrusion (0.8 to 1.5 mm pellet size) were prepared by substituting high-quality fish meal with 0, 3, and 6% SDPP. The diets were tested for a period of 60 d at 22°C with 4 replicates each (400-L cylindroconical tanks, 150 fish per tank, and initial density = 0.5 kg/m(3)). The SDPP inclusion in diets for gilthead sea bream fingerlings were evaluated in terms of growth performance, feed utilization, histological organization of the intestinal mucosa, activity of oxidative stress enzymes (catalase, glutathione S-transferase, glutathione peroxidase, and glutathione reductase) in the intestine, and nonspecific serum immune parameters (lysozyme and bactericidal activity). Results from this study indicated that dietary SDPP promoted fish growth in terms of BW and length; fish fed 3% SDPP were 10.5% heavier (P < 0.05) than those fed the control diet. Spray-dried plasma from porcine blood modulated the activity of the antioxidative defenses in the intestine (P < 0.05) and increased the density of goblet cells in the intestine (P < 0.05) and benefited the host by providing an effective immune barrier against gut pathogenic microbiota. The nonspecific serum immune response in fish fed diets with SDPP was greater (P < 0.05) than in fish fed the control diet. These results indicated that the inclusion of SDPP in gilthead sea bream feed could be beneficial for the fish by enhancing intestinal and serum innate immune

  16. Regulation of Phytosiderophore Release and Antioxidant Defense in Roots Driven by Shoot-Based Auxin Signaling Confers Tolerance to Excess Iron in Wheat

    PubMed Central

    Kabir, Ahmad H.; Khatun, Most A.; Hossain, Mohammad M.; Haider, Syed A.; Alam, Mohammad F.; Paul, Nishit K.

    2016-01-01

    Iron (Fe) is essential but harmful for plants at toxic level. However, how wheat plants tolerate excess Fe remains vague. This study aims at elucidating the mechanisms underlying tolerance to excess Fe in wheat. Higher Fe concentration caused morpho-physiological retardation in BR 26 (sensitive) but not in BR 27 (tolerant). Phytosiderophore and 2-deoxymugineic acid showed no changes in BR 27 but significantly increased in BR 26 due to excess Fe. Further, expression of TaSAMS. TaDMAS1, and TaYSL15 significantly downregulated in BR 27 roots, while these were upregulated in BR 26 under excess Fe. It confirms that inhibition of phytosiderophore directs less Fe accumulation in BR 27. However, phytochelatin and expression of TaPCS1 and TaMT1 showed no significant induction in response to excess Fe. Furthermore, excess Fe showed increased catalase, peroxidase, and glutathione reductase activities along with glutathione, cysteine, and proline accumulation in roots in BR 27. Interestingly, BR 27 self-grafts and plants having BR 26 rootstock attached to BR 27 scion had no Fe-toxicity induced adverse effect on morphology but showed BR 27 type expressions, confirming that shoot-derived signal triggering Fe-toxicity tolerance in roots. Finally, auxin inhibitor applied with higher Fe concentration caused a significant decline in morpho-physiological parameters along with increased TaSAMS and TaDMAS1 expression in roots of BR 27, revealing the involvement of auxin signaling in response to excess Fe. These findings propose that tolerance to excess Fe in wheat is attributed to the regulation of phytosiderophore limiting Fe acquisition along with increased antioxidant defense in roots driven by shoot-derived auxin signaling. PMID:27891139

  17. Environmental exposure to lead induces oxidative stress and modulates the function of the antioxidant defense system and the immune system in the semen of males with normal semen profile

    SciTech Connect

    Kasperczyk, Aleksandra; Dobrakowski, Michał; Czuba, Zenon P.; Horak, Stanisław; Kasperczyk, Sławomir

    2015-05-01

    We investigated the associations between environmental exposure to lead and a repertoire of cytokines in seminal plasma of males with normal semen profile according to the WHO criteria. Based on the median lead concentration in seminal plasma, 65 samples were divided into two groups: low (LE) and high exposure to lead (HE). Differences in semen volume and the pH, count, motility and morphology of sperm cells were not observed between the examined groups. The total oxidant status value and the level of protein sulfhydryl groups as well as the activities of manganese superoxide dismutase and catalase were significantly higher in the HE group, whereas the total antioxidant capacity value and the activities of glutathione reductase and glutathione-S-transferase were depressed. IL-7, IL-10, IL-12, and TNF-α levels were significantly higher in the HE group compared with the LE group. Environmental exposure to lead is sufficient to induce oxidative stress in seminal plasma and to modulate antioxidant defense system. - Highlights: • Lead induces oxidative stress in seminal plasma in human. • Lead modulates antioxidant defense system in seminal plasma in human. • Lead does not change a Th1/Th2 imbalance in seminal plasma in human.

  18. A bHLH-Type Transcription Factor, ABA-INDUCIBLE BHLH-TYPE TRANSCRIPTION FACTOR/JA-ASSOCIATED MYC2-LIKE1, Acts as a Repressor to Negatively Regulate Jasmonate Signaling in Arabidopsis[C][W

    PubMed Central

    Nakata, Masaru; Mitsuda, Nobutaka; Herde, Marco; Koo, Abraham J.K.; Moreno, Javier E.; Suzuki, Kaoru; Howe, Gregg A.; Ohme-Takagi, Masaru

    2013-01-01

    Jasmonates (JAs) are plant hormones that regulate the balance between plant growth and responses to biotic and abiotic stresses. Although recent studies have uncovered the mechanisms for JA-induced responses in Arabidopsis thaliana, the mechanisms by which plants attenuate the JA-induced responses remain elusive. Here, we report that a basic helix-loop-helix–type transcription factor, ABA-INDUCIBLE BHLH-TYPE TRANSCRIPTION FACTOR/JA-ASSOCIATED MYC2-LIKE1 (JAM1), acts as a transcriptional repressor and negatively regulates JA signaling. Gain-of-function transgenic plants expressing the chimeric repressor for JAM1 exhibited substantial reduction of JA responses, including JA-induced inhibition of root growth, accumulation of anthocyanin, and male fertility. These plants were also compromised in resistance to attack by the insect herbivore Spodoptera exigua. Conversely, jam1 loss-of-function mutants showed enhanced JA responsiveness, including increased resistance to insect attack. JAM1 and MYC2 competitively bind to the target sequence of MYC2, which likely provides the mechanism for negative regulation of JA signaling and suppression of MYC2 functions by JAM1. These results indicate that JAM1 negatively regulates JA signaling, thereby playing a pivotal role in fine-tuning of JA-mediated stress responses and plant growth. PMID:23673982

  19. Antioxidants of Edible Mushrooms.

    PubMed

    Kozarski, Maja; Klaus, Anita; Jakovljevic, Dragica; Todorovic, Nina; Vunduk, Jovana; Petrović, Predrag; Niksic, Miomir; Vrvic, Miroslav M; van Griensven, Leo

    2015-10-27

    Oxidative stress caused by an imbalanced metabolism and an excess of reactive oxygen species (ROS) lead to a range of health disorders in humans. Our endogenous antioxidant defense mechanisms and our dietary intake of antioxidants potentially regulate our oxidative homeostasis. Numerous synthetic antioxidants can effectively improve defense mechanisms, but because of their adverse toxic effects under certain conditions, preference is given to natural compounds. Consequently, the requirements for natural, alternative sources of antioxidant foods identified in edible mushrooms, as well as the mechanistic action involved in their antioxidant properties, have increased rapidly. Chemical composition and antioxidant potential of mushrooms have been intensively studied. Edible mushrooms might be used directly in enhancement of antioxidant defenses through dietary supplementation to reduce the level of oxidative stress. Wild or cultivated, they have been related to significant antioxidant properties due to their bioactive compounds, such as polyphenols, polysaccharides, vitamins, carotenoids and minerals. Antioxidant and health benefits, observed in edible mushrooms, seem an additional reason for their traditional use as a popular delicacy food. This review discusses the consumption of edible mushrooms as a powerful instrument in maintaining health, longevity and life quality.

  20. Functional dissection of an abscisic acid (ABA)-inducible gene reveals two independent ABA-responsive complexes each containing a G-box and a novel cis-acting element.

    PubMed Central

    Shen, Q; Ho, T H

    1995-01-01

    To elucidate the mechanism by which abscisic acid (ABA) regulates gene expression, the promoter of the barley ABA-responsive HVA22 gene has been analyzed by both loss- and gain-of-function studies. Previous reports indicate that G-box sequences, which are present in genes responding to a variety of environmental and physiological cues, are involved in ABA response. However, our data suggest that G-box sequences are necessary but not sufficient for ABA response. Instead, an ABA response complex consisting of a G-box, namely, ABRE3 (GCCACGTACA), and a novel coupling element, CE1 (TGCCACCGG), is sufficient for high-level ABA induction, and replacement of either of these sequences abolishes ABA responsiveness. We suggest that the interaction between G-box sequences, such as ABRE3 in the HVA22 gene, and CE-type sequences determines the specificity in ABA-regulated gene expression. Our results also demonstrate that the ABA response complex is the minimal promoter unit governing high-level ABA induction; four copies of this 49-bp-long complex linked to a minimal promoter can confer more than 100-fold ABA-induced gene expression. In addition to ABA response complex 1, composed of ABRE3 and CE1, the HVA22 promoter contains another ABA response complex. The ABA responsiveness of this ABA response complex 2 relies on the interaction of G-box (ABRE2; CGCACGTGTC) with another yet unidentified coupling element. These two complexes contribute incrementally to the expression level of HVA22 in response to ABA. PMID:7734964

  1. Differential antioxidant defense and detoxification mechanisms in photodynamically stressed rice plants treated with the deregulators of porphyrin biosynthesis, 5-aminolevulinic acid and oxyfluorfen

    SciTech Connect

    Phung, Thu-Ha; Jung, Sunyo

    2015-04-03

    This study focuses on differential molecular mechanisms of antioxidant and detoxification systems in rice plants under two different types of photodynamic stress imposed by porphyrin deregulators, 5-aminolevulinic acid (ALA) and oxyfluorfen (OF). The ALA-treated plants with white necrosis exhibited a greater decrease in photochemical quantum efficiency, F{sub v}/F{sub m}, as well as a greater increase in activity of superoxide dismutase, compared to the OF-treated plants. By contrast, the brown necrosis in OF-treated plants resulted in not only more widely dispersed H{sub 2}O{sub 2} production and greater increases in H{sub 2}O{sub 2}-decomposing enzymes, catalase and peroxidase, but also lower ascorbate redox state. In addition, ALA- and OF-treated plants markedly up-regulated transcript levels of genes involved in detoxification processes including transport and movement, cellular homeostasis, and xenobiotic conjugation, with prominent up-regulation of serine/threonine kinase and chaperone only in ALA-treated plants. Our results demonstrate that different photodynamic stress imposed by ALA and OF developed differential actions of antioxidant enzymes and detoxification. Particularly, detoxification system may play potential roles in plant protection against photodynamic stress imposed by porphyrin deregulators, thereby contributing to alleviation of photodynamic damage. - Highlights: • We employ two different types of photodynamic stress, white and brown necrosis. • We examine molecular mechanisms of antioxidative and detoxification systems. • ALA and OF develop differential actions of antioxidant and detoxification systems. • Coordinated mechanism of antioxidants and detoxification works against toxic ROS. • Detoxification system plays critical roles in protection against photodynamic stress.

  2. Self-report of Fruit and Vegetable Intake that meets the 5 A Day Recommendation is Associated with Reduced Levels of Oxidative Stress Biomarkers and Increased Levels of Antioxidant Defense in Premenopausal Women

    PubMed Central

    Rink, Stephanie M.; Mendola, Pauline; Mumford, Sunni L.; Poudrier, Jill K.; Browne, Richard W.; Wactawski-Wende, Jean; Perkins, Neil J.; Schisterman, Enrique F.

    2013-01-01

    Background Oxidative stress has been associated with a variety of chronic diseases and reproductive disorders. Fruits and vegetables may contribute to antioxidant vitamin and micronutrient levels and reduce oxidative stress. Objective To investigate the effect of meeting the 5 A Day recommendation for fruit and vegetable consumption on biomarkers of oxidative damage and antioxidant defense. Design In this longitudinal study, healthy premenopausal women (n=258) were followed for ≤2 menstrual cycles with ≤16 oxidative stress measures timed to cycle phase. Main outcome measures Plasma concentrations of F2-isoprostane, 9-hydroxyoctadecadieneoic acid (9-HODE), and 13-hydroxyoctadecadieneoic acid (13-HODE), erythrocyte activity of superoxide dismutase (SOD), glutathione reductase (GSHR), and glutathione peroxidase (GPx), as well as blood micronutrient concentrations were measured. Dietary intake was assessed by Food Frequency Questionnaires (FFQ, 1/cycle) and 24-hour recalls (≤4/cycle). Statistical analyses performed Fruit and vegetable servings were dichotomized based on the 5 A Day recommendation. Linear mixed models with repeated measures were used to analyze lipid peroxidation markers, antioxidant vitamins, and antioxidant enzymes by cycle phase and in association with usual fruit and vegetable intake. Results For both 24-hour recall (timed to cycle phase) and cycle-specific FFQ, meeting the 5 A Day recommendation was associated with decreased F2-isoprostanes (24-hour recall β= −0.10 (95% CI: −0.12, −0.07); FFQ β= −0.14 (95% CI: −0.18, −0.11)). GSHR was lower in association with typical 5A Day consumption by FFQ but not in the phase-specific analysis. Higher levels of ascorbic acid, lutein, β-carotene and β-cryptoxanthin were observed with both 5 A Day measures. Conclusions Meeting the 5 A Day recommendation was associated with lower oxidative stress and improved antioxidant status in analyses of typical diet (FFQ) and in menstrual cycle phase

  3. Dual effects of a mixture of grape pomace (Campbell Early) and Omija fruit ethanol extracts on lipid metabolism and the antioxidant defense system in diet-induced obese mice

    PubMed Central

    Han, Hye Jin; Jung, Un Ju; Kim, Hye-Jin; Moon, Byoung Seok; Cho, Su-Jung; Park, Yong Bok; Lee, Dong Gun

    2015-01-01

    BACKGROUND/OBJECTIVES We investigated the effects of a combination of grape pomace (Vitis labrusca, Campbell Early) and Omija fruit (Schizandra chinensis, Baillon) ethanol extracts on lipid metabolism and antioxidant defense system in diet-induced obese mice. MATERIALS/METHODS Forty male C57BL/6J mice were divided into four groups and fed high-fat diet (control group, CON) or high-fat diet added 0.5% grape pomace extract (GPE), 0.05% Omija fruit extract (OFE) or 0.5% GPE plus 0.05% OFE (GPE+OFE) for 12 weeks. RESULTS In contrast to the GPE- or OFE-supplemented groups, the GPE+OFE group showed significantly lower body weight and white adipose tissue weights than the CON group. Moreover, GPE+OFE supplementation significantly decreased plasma total cholesterol and increased the plasma HDL-cholesterol/total-cholesterol ratio (HTR) compared to the control diet. The hepatic triglyceride level was significantly lower in the GPE+OFE and GPE groups by increasing β-oxidation and decreasing lipogenic enzyme compared to the CON group. Furthermore, GPE+OFE supplementation significantly increased antioxidant enzyme activities with a simultaneous decrease in liver H2O2 content compared to the control diet. CONCLUSIONS Together our results suggest that supplementation with the GPE+OFE mixture may be more effective in improving adiposity, lipid metabolism and oxidative stress in high-fat diet-fed mice than those with GPE and OFE alone. PMID:26060533

  4. Effects of heat stress on antioxidant defense system, inflammatory injury, and heat shock proteins of Muscovy and Pekin ducks: evidence for differential thermal sensitivities.

    PubMed

    Zeng, Tao; Li, Jin-jun; Wang, De-qian; Li, Guo-qin; Wang, Gen-lin; Lu, Li-zhi

    2014-11-01

    Rising temperatures are severely affecting the mortality, laying performance, and meat quality of duck. Our aim was to investigate the effect of acute heat stress on the expression of heat shock proteins (HSPs: HSP90, 70, 60, 40, and 10) and inflammatory factors (nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2)) and antioxidant enzyme activity (superoxide dismutase (SOD), malondialdehybe (MDA), catalase (CAT), total antioxidant capacity (T-AOC)) in livers of ducks and to compare the thermal tolerance of Pekin and Muscovy ducks exposed to acute heat stress. Ducks were exposed to heat at 39 ± 0.5 °C for 1 h and then returned to 20 °C for 1 h followed by a 3-h recovery period. The liver and other tissues were collected from each individual for analysis. The mRNA levels of HSPs (70, 60, and 40) increased in both species, except for HSP10, which was upregulated in Muscovy ducks and had no difference in Pekin ducks after heat stress. Simultaneously, the mRNA level of HSP90 decreased in the stress group in both species. Morphological analysis indicated that heat stress induced tissue injury in both species, and the liver of Pekin ducks was severely damaged. The activities of several antioxidant enzymes increased in Muscovy duck liver, but decreased in Pekin duck. The mRNA levels of inflammatory factors were increased after heat stress in both duck species. These results suggested that heat stress could influence HSPs, inflammatory factors expression, and the activities of antioxidant enzymes. Moreover, the differential response to heat stress indicated that the Muscovy duck has a better thermal tolerance than does the Pekin duck.

  5. Enantioselective Modulatory Effects of Naringenin Enantiomers on the Expression Levels of miR-17-3p Involved in Endogenous Antioxidant Defenses

    PubMed Central

    Curti, Valeria; Di Lorenzo, Arianna; Rossi, Daniela; Martino, Emanuela; Capelli, Enrica; Collina, Simona; Daglia, Maria

    2017-01-01

    Naringenin is a flavanone present in citrus fruit as a mixture of chiral isomers. The numerous biological properties attributed to this compound include antioxidant and anti-inflammatory activities, even though the molecular mechanisms of these remain unknown. This study aims to evaluate the effects of racemic and enantiomeric naringenin on the expression levels of miR-17-3p, miR-25-5p and relative mRNA targets, to elucidate the mechanisms underlying these antioxidant and anti-inflammatory properties. Caco-2 cells, a well characterized in vitro model which mimics the intestinal barrier, were treated with subtoxic concentrations of racemate and enantiomers. The expression levels of miR-17-3p and miR-25-5p were determined by Real-Time PCR and were found to be decreased for both miRNAs. miR-17-3p behavior was in agreement with the increased levels of target mRNAs coding for two antioxidant enzymes, manganese-dependent superoxide dismutase (MnSOD) and glutathione peroxidase 2 (GPx2), while expression levels of miR-25-5p were not in agreement with its target mRNAs, coding for two pro-inflammatory cytokines, Tumor necrosis factor-alpha (TNF-α) and Interleukin-6 (IL-6). These results lead to the conclusion that naringenin could exert its antioxidant activity through epigenetic regulation operated by miRNAs, while anti-inflammatory activity is regulated by other miRNAs and/or mechanisms. PMID:28264488

  6. Salinity-induced accumulation of endogenous H2S and NO is associated with modulation of the antioxidant and redox defense systems in Nicotiana tabacum L. cv. Havana.

    PubMed

    da Silva, Cristiane Jovelina; Batista Fontes, Elizabeth Pacheco; Modolo, Luzia Valentina

    2017-03-01

    Salinity is one of the abiotic factors that most affect crop growth and production. This study focused on the effect of high salinity on the endogenous levels of the signaling molecules hydrogen sulfite (H2S) and nitric oxide (NO) in Nicotiana tabacum leaves and the extent of these for the biochemically-driven plant tolerance to such abiotic stress. The NaCl treatment for 10days led to an expressive augment of H2S and NO levels. This increase was correlated with the raise of l-Cys and l-Arg and the induction of l-cysteine desulfhydrase, cyanoalanine synthase, cysteine synthase, nitrate reductase and arginase, enzymes known to be involved in the biosynthesis of H2S or NO. The enzymatic antioxidant system (superoxide dismutase and catalase activity) was boosted and the non-enzymatic antioxidant glutathione was intensively oxidized in leaves upon stress allowing plants to cope with oxidative stress. Lower stomatal conductance was observed in stressed plants in comparison with control ones. Moreover, the high activity of antioxidant enzymes and high rate of glutathione oxidation following salt stress were considerably decreased upon NO or H2S scavenging. Thus, increment in NO and H2S levels and their interplay, along with metabolic and physiological changes, contributed to tobacco survival to extreme salinity conditions.

  7. Plant antioxidant gene responses to fungal pathogens.

    PubMed

    Williamson, J D; Scandalios, J G

    1993-09-01

    Antioxidant defense systems are a prominent element in plant responses to environmental stress. Activated oxygen species have themselves been implicated as both a part of the plant's defense against pathogen attack as well as the phytotoxic component of photosensitizing fungal toxins. Molecular analyses are just beginning to define how plant oxidant and antioxidant genes might integrate with other defense responses to provide effective protection against pathogen attack.

  8. Effect of zinc and polyphenols supplementation on antioxidative defense mechanisms and the frequency of microsatellite instability in chemically-induced mammary carcinogenesis in the rat.

    PubMed

    Bobrowska-Korczak, Barbara; Skrajnowska, Dorota; Tokarz, Andrzej; Bialek, Slawomir; Jezierska, Ewelina

    2015-01-01

    The aim of the present study was to assess the effect of dietary supplementation (with zinc or zinc and polyphenolic compounds - resveratrol or genistein) on antioxidant enzymes (glutathione peroxidase - GPx, catalase - CAT and superoxide dismutase - SOD) and the frequency of microsatellite instability (MSI) in a widely used model of mammary carcinogenesis induced in the rat by treatment with 7,12-dimethyl-1,2-benz[a]anthracene (DMBA). The impact of selected compounds on the intensity of DMBA-induced carcinogenesis was also assessed. Sixty four Sprague-Dawley female rats were divided into study groups which, apart from the standard diet and DMBA, were treated with zinc, zinc and resveratrol or zinc and genistein via gavage for a period ranging from 40 days to 20 weeks of age. On the basis of the obtained results it can be said that synergistic reaction between Zn(II) and genistein causes a delay in cancer development as compared with the animals treated with DMBA but with no food supplementation. Supplementation with Zn(II) and polyphenolic compounds resulted in the occurrence of microsatellite instabilities in tumors. LOH (loss of heterozygosity) was found in tumor samples at microsatellite D1Mgh6 and D3Mgh9. DMBA treatment increased significantly the glutathione peroxidase activity whereas it had no effect on the SOD and CAT activities, as compared with control rats. Diet supplementation has an effect on the activity of selected antioxidant enzymes. Diet supplementation has an effect on the occurrence of microsatellite instabilities as well as on the intensity of the neoplastic process. The intensity of occurrence of microsatellite instabilities does not depend on the activity of selected antioxidant enzymes.

  9. Age-related learning and memory deficits in rats: role of altered brain neurotransmitters, acetylcholinesterase activity and changes in antioxidant defense system.

    PubMed

    Haider, Saida; Saleem, Sadia; Perveen, Tahira; Tabassum, Saiqa; Batool, Zehra; Sadir, Sadia; Liaquat, Laraib; Madiha, Syeda

    2014-06-01

    Oxidative stress from generation of increased reactive oxygen species or free radicals of oxygen has been reported to play an important role in the aging. To investigate the relationship between the oxidative stress and memory decline during aging, we have determined the level of lipid peroxidation, activities of antioxidant enzymes, and activity of acetylcholine esterase (AChE) in brain and plasma as well as biogenic amine levels in brain from Albino-Wistar rats at age of 4 and 24 months. The results showed that the level of lipid peroxidation in the brain and plasma was significantly higher in older than that in the young rats. The activities of antioxidant enzymes displayed an age-dependent decline in both brain and plasma. Glutathione peroxidase and catalase activities were found to be significantly decreased in brain and plasma of aged rats. Superoxide dismutase (SOD) was also significantly decreased in plasma of aged rats; however, a decreased tendency (non-significant) of SOD in brain was also observed. AChE activity in brain and plasma was significantly decreased in aged rats. Learning and memory of rats in the present study was assessed by Morris Water Maze (MWM) and Elevated plus Maze (EPM) test. Short-term memory and long-term memory was impaired significantly in older rats, which was evident by a significant increase in the latency time in MWM and increase in transfer latency in EPM. Moreover, a marked decrease in biogenic amines (NA, DA, and 5-HT) was also found in the brain of aged rats. In conclusion, our data suggest that increased oxidative stress, decline of antioxidant enzyme activities, altered AChE activity, and decreased biogenic amines level in the brain of aged rats may potentially be involved in diminished memory function.

  10. Role of two-sided crosstalk between NO and H2S on improvement of mineral homeostasis and antioxidative defense in Sesamum indicum under lead stress.

    PubMed

    Amooaghaie, Rayhaneh; Zangene-Madar, Faezeh; Enteshari, Shekoofeh

    2017-05-01

    H2S and NO are two important gasotransmitters that modulate stress responses in plants. There are the contradictory data on crosstalk between NO and H2S in the studies. Hence, in the present study, the role of interplay between NO and H2S was assessed on the Pb tolerance of Sesamum indicum using pharmacological and biochemical approaches. Results revealed that Pb stress reduced the plant growth and the content of photosynthetic pigments and Fv/Fm ratio, increased the lipid peroxidation and the H2O2 content, elevated the endogenous contents of nitric oxide (NO), H2S and enhanced the activities of antioxidant enzymes (except APX). Additionally, concentrations of most mineral ions (K, P, Mg, Fe, Mn and Zn) in both shoots and roots decreased. Pb accumulation in roots was more than it in shoots. Both sodium hydrosulfide (NaHS as a donor of H2S) and sodium nitroprusside (SNP as an NO donor) improved the plant growth, the chlorophyll and carotenoid contents and PSII efficiency, reduced oxidative damage, increased the activities of antioxidant enzymes and reduced the proline content in Pb-stressed plants. Furthermore, both NaHS and SNP significantly restricted the uptake and translocation of Pb, thereby minimizing antagonistic effects of Pb on essential mineral contents in sesame plants. NaHS increased the NO generation and many NaHS-induced responses were completely reversed by cPTIO, as the specific NO scavenger. Applying SNP also enhanced H2S release levels in roots of Pb-stressed plants and only some NO-driven effects were partially weakened by hypotuarine (HT), as the scavenger of H2S.These findings proposed for the first time that two-sided interplay between H2S and NO might confer an increased tolerance to Pb stress via activating the antioxidant systems, reducing the uptake and translocation of Pb, and harmonizing the balance of mineral nutrient.

  11. Differential antioxidant defense and detoxification mechanisms in photodynamically stressed rice plants treated with the deregulators of porphyrin biosynthesis, 5-aminolevulinic acid and oxyfluorfen.

    PubMed

    Phung, Thu-Ha; Jung, Sunyo

    2015-04-03

    This study focuses on differential molecular mechanisms of antioxidant and detoxification systems in rice plants under two different types of photodynamic stress imposed by porphyrin deregulators, 5-aminolevulinic acid (ALA) and oxyfluorfen (OF). The ALA-treated plants with white necrosis exhibited a greater decrease in photochemical quantum efficiency, Fv/Fm, as well as a greater increase in activity of superoxide dismutase, compared to the OF-treated plants. By contrast, the brown necrosis in OF-treated plants resulted in not only more widely dispersed H2O2 production and greater increases in H2O2-decomposing enzymes, catalase and peroxidase, but also lower ascorbate redox state. In addition, ALA- and OF-treated plants markedly up-regulated transcript levels of genes involved in detoxification processes including transport and movement, cellular homeostasis, and xenobiotic conjugation, with prominent up-regulation of serine/threonine kinase and chaperone only in ALA-treated plants. Our results demonstrate that different photodynamic stress imposed by ALA and OF developed differential actions of antioxidant enzymes and detoxification. Particularly, detoxification system may play potential roles in plant protection against photodynamic stress imposed by porphyrin deregulators, thereby contributing to alleviation of photodynamic damage.

  12. Exogenous spermidine improves seed germination of white clover under water stress via involvement in starch metabolism, antioxidant defenses and relevant gene expression.

    PubMed

    Li, Zhou; Peng, Yan; Zhang, Xin-Quan; Ma, Xiao; Huang, Lin-Kai; Yan, Yan-Hong

    2014-11-05

    This study was designed to determine the effect of exogenous spermidine (Spd) (30 μM) on white clover seed germination under water stress induced by polyethylene glycol 6000. Use of seed priming with Spd improved seed germination percentage, germination vigor, germination index, root viability and length, and shortened mean germination time under different water stress conditions. Seedling fresh weight and dry weight also increased significantly in Spd-treated seeds compared with control (seeds primed with distilled water). Improved starch metabolism was considered a possible reason for this seed invigoration, since seeds primed with Spd had significantly increased α-amylase/β-amylase activities, reducing sugar, fructose and glucose content and transcript level of β-amylase gene but not transcript level of α-amylase gene. In addition, the physiological effects of exogenous Spd on improving seeds' tolerance to water deficit during germination were reflected by lower lipid peroxidation levels, better cell membrane stability and significant higher seed vigour index in seedlings. Enhanced antioxidant enzyme activities (superoxide dismutase, peroxidase, catalase and ascorbate peroxidase), ascorbate-glutathione cycle (ASC-GSH cycle) and transcript level of genes encoding antioxidant enzymes induced by exogenous Spd may be one of the critical reasons behind acquired drought tolerance through scavenging of reactive oxygen species (ROS) in water-stressed white clover seeds. The results indicate that Spd plays an important function as a stress-protective compound or physiological activator.

  13. Impact of proline application on cadmium accumulation, mineral nutrition and enzymatic antioxidant defense system of Olea europaea L. cv Chemlali exposed to cadmium stress.

    PubMed

    Zouari, Mohamed; Ben Ahmed, Chedlia; Elloumi, Nada; Bellassoued, Khaled; Delmail, David; Labrousse, Pascal; Ben Abdallah, Ferjani; Ben Rouina, Bechir

    2016-06-01

    Proline plays an important role in plant response to various environmental stresses. However, its involvement in mitigation of heavy metal stress in plants remains elusive. In this study, we examined the effectiveness of exogenous proline (10 and 20 mM) in alleviating cadmium induced inhibitory effects in young olive plants (Olea europaea L. cv. Chemlali) exposed to two Cd levels (10 and 30 mg CdCl2 kg(-1) soil). The Cd treatment induced substantial accumulation of Cd in both root and leaf tissues and a decrease in gas exchange, photosynthetic pigments contents, uptake of essential elements (Ca, Mg and K) and plant biomass. Furthermore, an elevation of antioxidant enzymes activities (superoxide dismutase, catalase, glutathione peroxydase) and proline content in association with relatively high amounts of hydrogen peroxide, thiobarbituric acid reactive substances and electrolyte leakage were observed. Interestingly, the application of exogenous proline alleviated the oxidative damage induced by Cd accumulation. In fact, Cd-stressed olive plants treated with proline showed an increase of antioxidant enzymes activities, photosynthetic activity, nutritional status, plant growth and oil content of olive fruit. Generally, it seems that proline supplementation alleviated the deleterious effects of young olive plants exposed to Cd stress.

  14. Linking chloroplast antioxidant defense to carbohydrate availability: the transcript abundance of stromal ascorbate peroxidase is sugar-controlled via ascorbate biosynthesis.

    PubMed

    Heiber, Isabelle; Cai, Wenguo; Baier, Margarete

    2014-01-01

    All genes encoding chloroplast antioxidant enzymes are nuclear-encoded and posttranscriptionally targeted to chloroplasts. The transcript levels of most of them decreased upon sucrose feeding like the transcript levels of many genes encoding components of the photosynthetic electron transport chain. However, the transcript abundance of stromal ascorbate peroxidase (s-APX; At4g08390) increased. Due to mild sugar application conditions, the plants kept the phosphorylation status of the ADP+ATP pool and the redox states of the NADPH+NADP+ and the ascorbate pools under control, which excludes them as signals in s-APX regulation. Correlation with ascorbate pool size regulation and comparison of transcript abundance regulation in the starch-biosynthetic mutant adg1, the ascorbate biosynthesis mutant vtc1, and the abscisic acid (ABA) biosynthetic mutant aba2 showed a link between sugar induction of s-APX and ascorbate biosynthesis.

  15. Euterpe edulis Extract but Not Oil Enhances Antioxidant Defenses and Protects against Nonalcoholic Fatty Liver Disease Induced by a High-Fat Diet in Rats

    PubMed Central

    Freitas, Rodrigo Barros; Novaes, Rômulo Dias; Gonçalves, Reggiani Vilela; Mendonça, Bianca Gazolla; Santos, Eliziária Cardoso; Ribeiro, Andréia Queiroz; Lima, Luciana Moreira; Fietto, Luciano Gomes; Peluzio, Maria do Carmo Gouveia

    2016-01-01

    We investigated the effects of E. edulis bioproducts (lyophilized pulp [LEE], defatted lyophilized pulp [LDEE], and oil [EO]) on nonalcoholic fatty liver disease (NAFLD) induced by a high-fat diet (HFD) in rats. All products were chemically analyzed. In vivo, 42 rats were equally randomized into seven groups receiving standard diet, HFD alone or combined with EO, LEE, or LDEE. After NAFLD induction, LEE, LDEE, or EO was added to the animals' diet for 4 weeks. LEE was rich in polyunsaturated fatty acids. From LEE degreasing, LDEE presented higher levels of anthocyanins and antioxidant capacity in vitro. Dietary intake of LEE and especially LDEE, but not EO, attenuated diet-induced NAFLD, reducing inflammatory infiltrate, steatosis, and lipid peroxidation in liver tissue. Although both E. edulis bioproducts were not hepatotoxic, only LDEE presented sufficient benefits to treat NAFLD in rats, possibly by its low lipid content and high amount of phenols and anthocyanins. PMID:27418954

  16. A combination of soy isoflavone supplementation and exercise improves lipid profiles and protects antioxidant defense-systems against exercise-induced oxidative stress in ovariectomized rats.

    PubMed

    Oh, Hea Young; Lim, Soyoung; Lee, Joo Min; Kim, Dae-Young; Ann, Eue-Soo; Yoon, Sun

    2007-01-01

    Menopause is often accompanied with weight gain, metabolic lipid abnormalities, and oxidative stress. In this study, we investigated the combined effects of exercise and soy isoflavone supplementation on the lipid profiles and antioxidant capacities of ovariectomized rats. Twenty-five female Sprague-Dawley rats were divided into 5 groups: sham-operated, ovariectomized (OVX), OVX with exercise (OVX+EX), OVX with soy isoflavone supplementation (OVX+ISO), and OVX with both soy isoflavones and exercise (OVX+ISO+EX). After 12 weeks of intervention, antioxidant status was evaluated in collected blood samples by the ferric reducing ability of plasma (FRAP), glutathione (GSH) content, and sodium oxide dismutase (SOD) activity. DNA damage in the lymphocytes was determined using alkaline single-cell gel electrophoresis (the Comet assay). Although there were no significant differences in weight gain and food intake, weight gain was lower in OVX+EX, OVX+ISO, and OVX+ISO+EX than in OVX. OVX+EX, OVX+ISO, and OVX+ ISO+EX showed a significant decrease in total cholesterol, triglycerides, and LDL-cholesterol compared to OVX. The soy isoflavone supplemented group had significantly increased FRAP values and GSH contents in contrast to no changes in the exercised group, whereas exercise markedly increased SOD activity and H2O2-induced DNA tail length and tail moment. Exercise with soy isoflavone supplementation significantly increased FRAP values and had no difference on SOD activity, including DNA damage. These results demonstrate that a combined treatment of moderate exercise and soy isoflavone supplementation could exert a beneficial effect on weight control and lipid profiles, and offer protection from exercise-induced oxidative stress in postmenopausal women.

  17. Salicylic acid alleviates aluminum toxicity in rice seedlings better than magnesium and calcium by reducing aluminum uptake, suppressing oxidative damage and increasing antioxidative defense.

    PubMed

    Pandey, Poonam; Srivastava, Rajneesh Kumar; Dubey, R S

    2013-05-01

    Aluminum toxicity is a major constraint to crop production in acid soils. The present study was undertaken to examine the comparative ameliorating effects of salicylic acid, Ca and Mg on Al toxicity in rice (Oryza sativa L.) seedlings grown in hydroponics. Al treatment (0.5 mM AlCl3) caused decrease in plant vigour, loss of root plasma membrane integrity, increased contents of O 2 (∙-) , H2O2, lipid peroxidation, protein carbonyls and decline in the level of protein thiol. Al treatment caused significant changes in activity of antioxidative enzymes in rice seedlings. Exogenously added salicylic acid (60 μM), Ca (1 mM) and Mg (0.25 mM) significantly alleviated Al toxicity effects in the seedlings marked by restoration of growth, suppression of Al uptake, restoration of root plasma membrane integrity and decline in O 2 (∙-) , H2O2, lipid peroxidation and protein carbonyl contents. Salicylic acid, Ca and Mg suppressed Al-induced increase in SOD, GPX and APX activities while it elevated Al-induced decline in CAT activity. By histochemical staining of O 2 (∙-) using NBT and H2O2 using DAB, it was further confirmed that added salicylic acid, Ca or Mg decreased Al-induced accumulation of O 2 (∙-) and H2O2 in the leaf tissues. Results indicate that exogenously added salicylic acid, Ca or Mg alleviates Al toxicity in rice seedlings by suppressing Al uptake, restoring root membrane integrity, reducing ROS level and ROS induced oxidative damage and regulating the level of antioxidative enzyme activities. Further salicylic appears to be superior to Mg and Ca in alleviating Al toxicity effects in rice plants.

  18. Irradiation influence on the phenoloxidase pathway and an anti-oxidant defense mechanism in Spodoptera litura (Lepidoptera: Noctuidae) and its implication in radio-genetic 'F 1 sterility' and biorational pest suppression tactics.

    PubMed

    Sachdev, B; Khan, Z; Zarin, M; Malhotra, P; Seth, R K; Bhatnagar, R K

    2017-01-31

    The present study was conducted to appraise the ontogenic radio-sensitivity of a serious tropical pest, Spodoptera litura (Fabr.). The molecular responses pertaining to the phenoloxidase (PO) pathway and an anti-oxidant defense mechanism were evaluated in order to understand its implication in pest control at pre-harvest and post-harvest intervals. Irradiation exhibited an inverse relationship with age with respect to impact on developmental and transcriptional responses. Transcript abundance of PO cascade enzymes, prophenoloxidase (slppo-2), its activating enzyme (slppae-1) and free-radical scavenging enzymes, superoxide dismutase (slsod) and catalase (slcat) was evaluated upon gamma irradiation alone and the dual-stress of radiation plus microbial challenge. The slppo-2, slppae-1, slsod and slcat transcripts were significantly up-regulated in F 1 L6 larvae (6th-instar) resulting from 100 Gy sub-sterilized male adults and unirradiated female moths. The extent of upregulation was relatively higher in comparison with L6 survivors (6th-instar larvae) developed from irradiated neonates (L1) treated with 100 Gy. Upon Photorhabdus challenge, the transcripts were down-regulated in irradiated L1 suggesting increased larval susceptibility to bacterial infections. Radioresistance increased with the age of the insect, and molecular responses (transcript abundance) of insect defense mechanism were less influenced when older age (F 1 progeny) were irradiated. These findings will help to optimize the gamma dose to be employed in inherited sterility technique for (pre-harvest) pest suppression and (post-harvest) phytosanitation and quarantine, and suggest compatible integration of biorational tactics including nuclear technology.

  19. Tert-butylhydroquinone attenuates the ethanol-induced apoptosis of and activates the Nrf2 antioxidant defense pathway in H9c2 cardiomyocytes

    PubMed Central

    SHI, XIAOJING; LI, YANG; HU, JUN; YU, BO

    2016-01-01

    Tert-butylhydroquinone (tBHQ), an inducer of nuclear factor erythroid 2-related factor 2 (Nrf2), has been demonstrated to attenuate oxidative stress-induced injury and the apoptosis of human neural stem cells and other cell types. However, whether tBHQ is able to exert a protective effect against oxidative stress and the apoptosis of cardiomyocytes has not yet been determined. Thus, the objective of the present study was to determine whether tBHQ protects H9c2 cardiomyocytes against ethanol-induced apoptosis. For this purpose, four sets of experiments were performed under standard culture conditions as follows: i) untreated control cells; ii) cell treatment with 200 mM ethanol; iii) cell treatment with 5 µM tBHQ; and iv) cell pre-treatment with 5 µM tBHQ for 24 h, followed by medium change and co-culture with 200 mM ethanol containing 5 µM tBHQ for a further 24 h. The viability of the cardiomyocytes was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of intracellular reactive oxygen species (ROS) and apoptosis were assessed by flow cytometry. Protein expression was measured by western blot analysis, and Nrf2 nuclear localization was observed by immunofluorescence. Exposure to ethanol led to a decrease in the protein expression of Nrf2 and its downstream antioxidant enzymes, accompanied by an increase in ROS generation and in the apoptosis of H9c2 cells. Pre-treatment with tBHQ significantly prevented the H9c2 cells from undergoing ethanol-induced apoptosis. tBHQ also increased the expression of B-cell lymphoma-2 (Bcl-2), whereas Bcl-2-associated X protein (Bax) expression was decreased. tBHQ promoted Nrf2 nuclear localization and increased the expression of Nrf2, superoxide dismutase (SOD), catalase (CAT) and heme oxygenase-1 (HO-1), and simultaneously inhibited the ethanol-induced overproduction of intracellular ROS. Therefore, tBHQ confers protection against the ethanol-induced apoptosis of and activates the

  20. Polyamine and nitric oxide crosstalk: Antagonistic effects on cadmium toxicity in mung bean plants through upregulating the metal detoxification, antioxidant defense and methylglyoxal detoxification systems.

    PubMed

    Nahar, Kamrun; Hasanuzzaman, Mirza; Alam, Md Mahabub; Rahman, Anisur; Suzuki, Toshisada; Fujita, Masayuki

    2016-04-01

    Cadmium (Cd) contamination is a serious agricultural and environmental hazard. The study investigates cross-protection roles of putrescine (Put, 0.2 mM) and nitric oxide (sodium nitroprusside; SNP, 1 mM) in conferring Cd (CdCl2, 1.5 mM) tolerance in mung bean (Vigna radiata L. cv. BARI Mung-2) seedlings. Cadmium stress increased root and shoot Cd content, reduced growth, destroyed chlorophyll (chl), modulated proline (Pro) and reduced leaf relative water content (RWC), increased oxidative damage [lipid peroxidation, H2O2 content, O2(∙-) generation rate, lipoxygenase (LOX) activity], methylglyoxal (MG) toxicity. Put and/or SNP reduced Cd uptake, increasd phytochelatin (PC) content, reduced oxidative damage enhancing non-enzymatic antioxidants (AsA and GSH) and activities of enzymes [superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione S-transferase (GST), and glutathione peroxidase (GPX)]. Exogenous Put and/or SNP modulated endogenous polyamines, PAs (putrescine, Put; spermidine, Spd; spermine, Spm), and NO; improved glyoxalase system in detoxifying MG and improved physiology and growth where combined application showed better effects which designates possible crosstalk between NO and PAs to confer Cd-toxicity tolerance.

  1. Protective effect of chitosan on photosynthesis and antioxidative defense system in edible rape (Brassica rapa L.) in the presence of cadmium.

    PubMed

    Zong, Haiying; Liu, Song; Xing, Ronge; Chen, Xiaolin; Li, Pengcheng

    2017-04-01

    Chitosan (CTS) induces plant tolerance against several abiotic stresses, including salinity and drought exposure. However, the role of CTS in cadmium (Cd)-induced stress amelioration is largely unknown. In the present study, a hydroponic pot experiment was conducted to study the roles of CTS with different molecular weight (Mw) (10kDa,5kDa and 1kDa) in alleviating Cd toxicity in edible rape (Brassica rapa L .). The results showed that Cd stress significantly decreased plant growth, leaf chlorophyll contents and increased the malondialdehyde (MDA) level in rape leaves. Foliar application of CTS promoted the plant growth and leaf chlorophyll contents, and decreased the malondialdehyde (MDA) level in edible rape leaves under Cd stress. The alleviation effect of CTS on toxicity was depended on its Mw and CTS with Mw of 1kDa showed the best activity. Spraying 1kDa CTS onto the leaves of edible rape under Cd-toxicity could decrease shoot Cd(2+) concentration and improve photosynthetic characteristics of edible rape. Moreover, 1kDa CTS also significantly enhanced non-enzymatic antioxidants (ascorbic acid) and enzyme activities (superoxide dismutase, catalase and guaiacol peroxidase) under Cd stress. Based on these findings, it can be concluded that application of exogenous CTS could be an effective approach to alleviate the harmful effects of Cd stress and could be explored in an agricultural production system.

  2. Responses of glutathione-related antioxidant defense system in serum of Nile tilapia (Oreochromis niloticus) exposed to sublethal concentration of methomyl and recovery pattern.

    PubMed

    Meng, Shun-Long; Qu, Jian-Hong; Fan, Li-Min; Qiu, Li-Ping; Chen, Jia-Zhang; Xu, Pao

    2015-04-01

    Tilapia were exposed to sublethal concentrations of 0, 0.2, 2, 20, or 200 μg/L for 30 days, and then transferred to methomyl-free water for 18 days. GST, GPx, GR, GSH, and GSSG in tilapia serum were examined at 0, 6, 12, 18, 24, and 30 days after methomyl exposure and at 18 days after transferring to methomyl-free water. There were no significant changes in antioxidants activities and contents in serum of tilapia exposed to 0.2 μg/L. Significant increases in GST, GR, GPx, and GSSG accompanied by a decrease in GSH were observed following methomyl exposure to 2, 20, or 200 μg/L, suggesting the presence of oxidative stress. Thus, it would appear the 0.2 μg/L methomyl might be considered the no observed adverse effect level. Recovery data showed that the effects produced by lower concentration of 20 μg/L were reversible but not at the higher 200 μg/L concentration.

  3. Defensive Armor of Potato Tubers: Nonpolar Metabolite Profiling, Antioxidant Assessment, and Solid-State NMR Compositional Analysis of Suberin-Enriched Wound-Healing Tissues

    PubMed Central

    Dastmalchi, Keyvan; Kallash, Linda; Wang, Isabel; Phan, Van C.; Huang, Wenlin; Serra, Olga; Stark, Ruth E.

    2016-01-01

    The cultivation, storage, and distribution of potato tubers are compromised by mechanical damage and suboptimal healing. To investigate wound-healing progress in cultivars with contrasting russeting patterns, metabolite profiles reported previously for polar tissue extracts were complemented by GC/MS measurements for nonpolar extracts and quantitative 13C NMR of interfacial solid suspensions. Potential marker compounds that distinguish cultivar type and wound-healing time point included fatty acids, fatty alcohols, alkanes, glyceryl esters, α,ω-fatty diacids, and hydroxyfatty acids. The abundant long-chain fatty acids in nonpolar extracts and solids from the smooth-skinned Yukon Gold cultivar suggested extensive suberin biopolymer formation; this hypothesis was supported by high proportions of arenes, alkenes, and carbonyl groups in the solid and among the polar markers. The absence of many potential marker classes in nonpolar Atlantic extracts and interfacial solids suggested a limited extent of suberization. Modest scavenging activities of all nonpolar extracts indicate that the majority of antioxidants produced in response to wounding are polar. PMID:26166447

  4. Defensive Armor of Potato Tubers: Nonpolar Metabolite Profiling, Antioxidant Assessment, and Solid-State NMR Compositional Analysis of Suberin-Enriched Wound-Healing Tissues.

    PubMed

    Dastmalchi, Keyvan; Kallash, Linda; Wang, Isabel; Phan, Van C; Huang, Wenlin; Serra, Olga; Stark, Ruth E

    2015-08-05

    The cultivation, storage, and distribution of potato tubers are compromised by mechanical damage and suboptimal healing. To investigate wound-healing progress in cultivars with contrasting russeting patterns, metabolite profiles reported previously for polar tissue extracts were complemented by GC/MS measurements for nonpolar extracts and quantitative (13)C NMR of interfacial solid suspensions. Potential marker compounds that distinguish cultivar type and wound-healing time point included fatty acids, fatty alcohols, alkanes, glyceryl esters, α,ω-fatty diacids, and hydroxyfatty acids. The abundant long-chain fatty acids in nonpolar extracts and solids from the smooth-skinned Yukon Gold cultivar suggested extensive suberin biopolymer formation; this hypothesis was supported by high proportions of arenes, alkenes, and carbonyl groups in the solid and among the polar markers. The absence of many potential marker classes in nonpolar Atlantic extracts and interfacial solids suggested a limited extent of suberization. Modest scavenging activities of all nonpolar extracts indicate that the majority of antioxidants produced in response to wounding are polar.

  5. SWATH label-free proteomics analyses revealed the roles of oxidative stress and antioxidant defensing system in sclerotia formation of Polyporus umbellatus

    NASA Astrophysics Data System (ADS)

    Li, Bing; Tian, Xiaofang; Wang, Chunlan; Zeng, Xu; Xing, Yongmei; Ling, Hong; Yin, Wanqiang; Tian, Lixia; Meng, Zhixia; Zhang, Jihui; Guo, Shunxing

    2017-01-01

    Understanding the initiation and maturing mechanisms is important for rational manipulating sclerotia differentiation and growth from hypha of Polyporus umbellatus. Proteomes in P. umbellatus sclerotia and hyphae at initial, developmental and mature phases were studied. 1391 proteins were identified by nano-liquid chromatograph-mass spectrometry (LC-MS) in Data Dependant Acquisition mode, and 1234 proteins were quantified successfully by Sequential Window Acquisition of all THeoretical fragment ion spectra-MS (SWATH-MS) technology. There were 347 differentially expressed proteins (DEPs) in sclerotia at initial phase compared with those in hypha, and the DEP profiles were dynamically changing with sclerotia growth. Oxidative stress (OS) in sclerotia at initial phase was indicated by the repressed proteins of respiratory chain, tricarboxylic acid cycle and the activation of glycolysis/gluconeogenesis pathways were determined based on DEPs. The impact of glycolysis/gluconeogenesis on sclerotium induction was further verified by glycerol addition assays, in which 5% glycerol significantly increased sclerotial differentiation rate and biomass. It can be speculated that OS played essential roles in triggering sclerotia differentiation from hypha of P. umbellatus, whereas antioxidant activity associated with glycolysis is critical for sclerotia growth. These findings reveal a mechanism for sclerotial differentiation in P. umbellatus, which may also be applicable for other fungi.

  6. Dietary flavanols exert different effects on antioxidant defenses and apoptosis/proliferation in Caco-2 and SW480 colon cancer cells.

    PubMed

    Ramos, Sonia; Rodríguez-Ramiro, Ildefonso; Martín, María Angeles; Goya, Luis; Bravo, Laura

    2011-12-01

    Flavanols intake has been associated with reduced risk of cancer. In this study, the anticarcinogenic effects of the flavanols epicatechin (EC), epicatechin-gallate (ECG) and procyanidin B2 (PB2) on Caco-2 and SW480 colon cancer cells were investigated. Catechins showed different cytotoxicity depending on the cell line. ECG displayed strong growth inhibitory effects against SW480 cells, but was ineffective on Caco-2 cells. In contrast, PB2 did not affect Caco-2 cells, whereas promoted cell growth in SW480 cells and EC had no obvious effects on any cell line. Exposure of SW480 cells to ECG led to apoptosis as determined by caspase-3 activity, imbalance among Bcl-2 anti- and pro-apoptotic protein levels, ERK activation and AKT inhibition, whereas PB2 treatment enhanced phospho-AKT and phospho-ERK levels. Incubation of Caco-2 cells with ECG increased glutathione levels without affecting the expression of pro- and anti-apoptotic Bcl-2 proteins, AKT or ERK. The results suggest that the different cytotoxicity of flavanols is caused by their different activity and the degree of differentiation of the colon cancer cell line. Thus, ECG induced apoptosis in SW480 cells and contributed to the cytotoxic effect, whereas ECG enhanced the antioxidant potential in Caco-2 cells. PB2 activated cell proliferation and survival/proliferation pathways in SW480 cells.

  7. SWATH label-free proteomics analyses revealed the roles of oxidative stress and antioxidant defensing system in sclerotia formation of Polyporus umbellatus

    PubMed Central

    Li, Bing; Tian, Xiaofang; Wang, Chunlan; Zeng, Xu; Xing, Yongmei; Ling, Hong; Yin, Wanqiang; Tian, Lixia; Meng, Zhixia; Zhang, Jihui; Guo, Shunxing

    2017-01-01

    Understanding the initiation and maturing mechanisms is important for rational manipulating sclerotia differentiation and growth from hypha of Polyporus umbellatus. Proteomes in P. umbellatus sclerotia and hyphae at initial, developmental and mature phases were studied. 1391 proteins were identified by nano-liquid chromatograph-mass spectrometry (LC-MS) in Data Dependant Acquisition mode, and 1234 proteins were quantified successfully by Sequential Window Acquisition of all THeoretical fragment ion spectra-MS (SWATH-MS) technology. There were 347 differentially expressed proteins (DEPs) in sclerotia at initial phase compared with those in hypha, and the DEP profiles were dynamically changing with sclerotia growth. Oxidative stress (OS) in sclerotia at initial phase was indicated by the repressed proteins of respiratory chain, tricarboxylic acid cycle and the activation of glycolysis/gluconeogenesis pathways were determined based on DEPs. The impact of glycolysis/gluconeogenesis on sclerotium induction was further verified by glycerol addition assays, in which 5% glycerol significantly increased sclerotial differentiation rate and biomass. It can be speculated that OS played essential roles in triggering sclerotia differentiation from hypha of P. umbellatus, whereas antioxidant activity associated with glycolysis is critical for sclerotia growth. These findings reveal a mechanism for sclerotial differentiation in P. umbellatus, which may also be applicable for other fungi. PMID:28134344

  8. Antioxidant defense of Nrf2 vs pro-inflammatory system of NF-κB during the amoebic liver infection in hamster.

    PubMed

    Aldaba-Muruato, Liseth R; Muñoz-Ortega, Martin H; Campos-Esparza, María Del R; Macías-Pérez, José R; Márquez-Muñoz, Nayeli A; Villalobos-Santos, Ana G; Ventura-Juárez, Javier

    2017-04-01

    Entamoeba histolytica is the causative agent of amoebic liver abscess (ALA), which course with an uncontrolled inflammation and nitro-oxidative stresses, although it is well known that amoeba has an effective defence mechanisms against this toxic environment, the underlying molecular factors responsible for progression of tissue damage remain largely unknown. The purpose of the present study was to determine during the acute stage of ALA in hamsters, the involvement of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and nuclear factor-kappa B (NF-κB), which are activated in response to oxidative stress. From 12 h post-infection the ALA was visible, haematoxylin-eosin and Masson's trichrome stains were consistent with these observations, and alanine aminotransferase, alkaline phosphatase and γ-glutamyl transpeptidase serum activities were increased too. At 48 h after infection, liver glycogen content was significantly reduced. Western blot analyses showed that 4-Hydroxy-2-nonenal peaked at 12 h, while glycogen synthase kinase-3β, cleaved caspase-3, pNF-κB, interleukin-1β and tumour necrosis factor-α were overexpressed from 12 to 48 h post-infection. Otherwise, Nrf2 and superoxide dismutase-1, decreased at 48 h and catalase declined at 36 and 48 h. Furthermore, heme oxygenase-1 was increased at 12 and 24 h and decreased to normal levels at 36 and 48 h. These findings suggest for the first time that the host antioxidant system of Nrf2 is influenced during ALA.

  9. β-Radiation Stress Responses on Growth and Antioxidative Defense System in Plants: A Study with Strontium-90 in Lemna minor

    PubMed Central

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-01-01

    In the following study, dose dependent effects on growth and oxidative stress induced by β-radiation were examined to gain better insights in the mode of action of β-radiation induced stress in plant species. Radiostrontium (90Sr) was used to test for β-radiation induced responses in the freshwater macrophyte Lemna minor. The accumulation pattern of 90Sr was examined for L. minor root and fronds separately over a seven-day time period and was subsequently used in a dynamic dosimetric model to calculate β-radiation dose rates. Exposing L. minor plants for seven days to a 90Sr activity concentration of 25 up to 25,000 kBq·L−1 resulted in a dose rate between 0.084 ± 0.004 and 97 ± 8 mGy·h−1. After seven days of exposure, root fresh weight showed a dose dependent decrease starting from a dose rate of 9.4 ± 0.5 mGy·h−1. Based on these data, an EDR10 value of 1.5 ± 0.4 mGy·h−1 was estimated for root fresh weight and 52 ± 17 mGy·h−1 for frond fresh weight. Different antioxidative enzymes and metabolites were further examined to analyze if β-radiation induces oxidative stress in L. minor. PMID:26198226

  10. Gene Expression Analysis Reveals the Concurrent Activation of Proapoptotic and Antioxidant-Defensive Mechanisms in Flavokawain B-Treated Cervical Cancer HeLa Cells.

    PubMed

    Yeap, Swee Keong; Abu, Nadiah; Akthar, Nadeem; Ho, Wan Yong; Ky, Huynh; Tan, Sheau Wei; Alitheen, Noorjahan Banu; Kamarul, Tunku

    2016-07-24

    Flavokawain B (FKB) is known to possess promising anticancer abilities. This is demonstrated in various cancer cell lines including HeLa cells. Cervical cancer is among the most widely diagnosed cancer among women today. Though FKB has been shown to be effective in treating cancer cells, the exact molecular mechanism is still unknown. This study is aimed at understanding the effects of FKB on HeLa cells using a microarray-based mRNA expression profiling and proteome profiling of stress-related proteins. The results of this study suggest that FKB induced cell death through p21-mediated cell cycle arrest and activation of p38. However, concurrent activation of antioxidant-related pathways and iron sequestration pathway followed by activation of ER-resident stress proteins clearly indicate that FKB failed to induce apoptosis in HeLa cells via oxidative stress. This effect implies that the protection of HeLa cells by FKB from H2O2-induced cell death is via neutralization of reactive oxygen species.

  11. A time course assessment of changes in reactive oxygen species generation and antioxidant defense in hydroponically grown wheat in response to lead ions (Pb2+).

    PubMed

    Kaur, Gurpreet; Singh, Harminder Pal; Batish, Daizy Rani; Kohli, Ravinder Kumar

    2012-10-01

    We examined the effect of Pb(2+) (8 and 40 mg l(-1)) on reactive oxygen species generation and alterations in antioxidant enzymes in hydroponically grown wheat at 24, 72, and 120 h after exposure. Pb(2+) toxicity was more pronounced on root growth, and it correlated with the greater Pb accumulation in roots. Pb exposure (40 mg l(-1)) enhanced superoxide anion, H(2)O(2), and MDA content in wheat roots by 1.9- to 2.2-folds, 56-255%, and 41-90%, respectively, over the control. Pb-induced loss of membrane integrity was confirmed by the enhanced electrolyte leakage and in vivo histochemical localization. Activities of scavenging enzymes, superoxide dismutases and catalases, enhanced in Pb-treated wheat roots by 1.4- to 5.7-folds over that in the control. In contrast, the activities of ascorbate and guaiacol peroxidases and glutathione reductases decreased significantly, suggesting their non-involvement in detoxification process. The study concludes that Pb(2+)-induced oxidative damage in wheat roots involve greater H(2)O(2) accumulation and the deactivation of the related scavenging enzymes.

  12. Deciphering Staphylococcus sciuri SAT-17 Mediated Anti-oxidative Defense Mechanisms and Growth Modulations in Salt Stressed Maize (Zea mays L.)

    PubMed Central

    Akram, Muhammad S.; Shahid, Muhammad; Tariq, Mohsin; Azeem, Muhammad; Javed, Muhammad T.; Saleem, Seemab; Riaz, Saba

    2016-01-01

    Soil salinity severely affects plant nutrient use efficiency and is a worldwide constraint for sustainable crop production. Plant growth-promoting rhizobacteria, with inherent salinity tolerance, are able to enhance plant growth and productivity by inducing modulations in various metabolic pathways. In the present study, we reported the isolation and characterization of a salt-tolerant rhizobacterium from Kallar grass [Leptochloa fusca (L.) Kunth]. Sequencing of the 16S rRNA gene revealed its lineage to Staphylococcus sciuri and it was named as SAT-17. The strain exhibited substantial potential of phosphate solubilization as well as indole-3-acetic acid production (up to 2 M NaCl) and 1-aminocyclopropane-1-carboxylic acid deaminase activity (up to 1.5 M NaCl). Inoculation of a rifampicin-resistant derivative of the SAT-17 with maize, in the absence of salt stress, induced a significant increase in plant biomass together with decreased reactive oxygen species and increased activity of cellular antioxidant enzymes. The derivative strain also significantly accumulated nutrients in roots and shoots, and enhanced chlorophyll and protein contents in comparison with non-inoculated plants. Similar positive effects were observed in the presence of salt stress, although the effect was more prominent at 75 mM in comparison to higher NaCl level (150 mM). The strain survived in the rhizosphere up to 30 days at an optimal population density (ca. 1 × 106 CFU mL-1). It was concluded that S. sciuri strain SAT-17 alleviated maize plants from salt-induced cellular oxidative damage and enhanced growth. Further field experiments should be conducted, considering SAT-17 as a potential bio-fertilizer, to draw parallels between PGPR inoculation, elemental mobility patterns, crop growth and productivity in salt-stressed semi-arid and arid regions. PMID:27375588

  13. The response of carbon metabolism and antioxidant defenses of alfalfa nodules to drought stress and to the subsequent recovery of plants.

    PubMed

    Naya, Loreto; Ladrera, Ruben; Ramos, Javier; González, Esther M; Arrese-Igor, Cesar; Minchin, Frank R; Becana, Manuel

    2007-06-01

    Alfalfa (Medicago sativa) plants were exposed to drought to examine the involvement of carbon metabolism and oxidative stress in the decline of nitrogenase (N(2)ase) activity. Exposure of plants to a moderate drought (leaf water potential of -1.3 MPa) had no effect on sucrose (Suc) synthase (SS) activity, but caused inhibition of N(2)ase activity (-43%), accumulation of succinate (+36%) and Suc (+58%), and up-regulation of genes encoding cytosolic CuZn-superoxide dismutase (SOD), plastid FeSOD, cytosolic glutathione reductase, and bacterial MnSOD and catalases B and C. Intensification of stress (-2.1 MPa) decreased N(2)ase (-82%) and SS (-30%) activities and increased malate (+40%), succinate (+68%), and Suc (+435%). There was also up-regulation (mRNA) of cytosolic ascorbate peroxidase and down-regulation (mRNA) of SS, homoglutathione synthetase, and bacterial catalase A. Drought stress did not affect nifH mRNA level or leghemoglobin expression, but decreased MoFe- and Fe-proteins. Rewatering of plants led to a partial recovery of the activity (75%) and proteins (>64%) of N(2)ase, a complete recovery of Suc, and a decrease of malate (-48%) relative to control. The increase in O(2) diffusion resistance, the decrease in N(2)ase-linked respiration and N(2)ase proteins, the accumulation of respiratory substrates and oxidized lipids and proteins, and the up-regulation of antioxidant genes reveal that bacteroids have their respiratory activity impaired and that oxidative stress occurs in nodules under drought conditions prior to any detectable effect on SS or leghemoglobin. We conclude that a limitation in metabolic capacity of bacteroids and oxidative damage of cellular components are contributing factors to the inhibition of N(2)ase activity in alfalfa nodules.

  14. Impairment of enzymatic antioxidant defenses is associated with bilirubin-induced neuronal cell death in the cerebellum of Ugt1 KO mice.

    PubMed

    Bortolussi, G; Codarin, E; Antoniali, G; Vascotto, C; Vodret, S; Arena, S; Cesaratto, L; Scaloni, A; Tell, G; Muro, A F

    2015-05-07

    Severe hyperbilirubinemia is toxic during central nervous system development. Prolonged and uncontrolled high levels of unconjugated bilirubin lead to bilirubin-induced encephalopathy and eventually death by kernicterus. Despite extensive studies, the molecular and cellular mechanisms of bilirubin toxicity are still poorly defined. To fill this gap, we investigated the molecular processes underlying neuronal injury in a mouse model of severe neonatal jaundice, which develops hyperbilirubinemia as a consequence of a null mutation in the Ugt1 gene. These mutant mice show cerebellar abnormalities and hypoplasia, neuronal cell death and die shortly after birth because of bilirubin neurotoxicity. To identify protein changes associated with bilirubin-induced cell death, we performed proteomic analysis of cerebella from Ugt1 mutant and wild-type mice. Proteomic data pointed-out to oxidoreductase activities or antioxidant processes as important intracellular mechanisms altered during bilirubin-induced neurotoxicity. In particular, they revealed that down-representation of DJ-1, superoxide dismutase, peroxiredoxins 2 and 6 was associated with hyperbilirubinemia in the cerebellum of mutant mice. Interestingly, the reduction in protein levels seems to result from post-translational mechanisms because we did not detect significant quantitative differences in the corresponding mRNAs. We also observed an increase in neuro-specific enolase 2 both in the cerebellum and in the serum of mutant mice, supporting its potential use as a biomarker of bilirubin-induced neurological damage. In conclusion, our data show that different protective mechanisms fail to contrast oxidative burst in bilirubin-affected brain regions, ultimately leading to neurodegeneration.

  15. Characterization of a 1-cysteine peroxiredoxin from big-belly seahorse (Hippocampus abdominalis); insights into host antioxidant defense, molecular profiling and its expressional response to septic conditions.

    PubMed

    Godahewa, G I; Perera, N C N; Elvitigala, Don Anushka Sandaruwan; Jayasooriya, R G P T; Kim, Gi-Young; Lee, Jehee

    2016-10-01

    1-cysteine peroxiredoxin (Prx6) is an antioxidant enzyme that protects cells by detoxifying multiple peroxide species. This study aimed to describe molecular features, functional assessments and potential immune responses of Prx6 identified from the big-belly seahorse, Hippocampus abdominalis (HaPrx6). The complete ORF (666 bp) of HaPrx6 encodes a polypeptide (24 kDa) of 222 amino acids, and harbors a prominent peroxiredoxin super-family domain, a peroxidatic catalytic center, and a peroxidatic cysteine. The deduced amino acid sequence of HaPrx6 shares a relatively high amino acid sequence similarity and close evolutionary relationship with Oplegnathus fasciatus Prx6. The purified recombinant HaPrx6 protein (rHaPrx6) was shown to protect plasmid DNA in the Metal Catalyzed Oxidation (MCO) assay and, together with 1,4-Dithiothreitol (DTT), protected human leukemia THP-1 cells from extracellular H2O2-mediated cell death. In addition, quantitative real-time PCR revealed that HaPrx6 mRNA was constitutively expressed in 14 different tissues, with the highest expression observed in liver tissue. Inductive transcriptional responses were observed in liver and kidney tissues of fish after treating them with bacterial stimuli, including LPS, Edwardsiella tarda, and Streptococcus iniae. These results suggest that HaPrx6 may play an important role in the immune response of the big-belly seahorse against microbial infection. Collectively, these findings provide structural and functional insights into HaPrx6.

  16. Impairment of enzymatic antioxidant defenses is associated with bilirubin-induced neuronal cell death in the cerebellum of Ugt1 KO mice

    PubMed Central

    Bortolussi, G; Codarin, E; Antoniali, G; Vascotto, C; Vodret, S; Arena, S; Cesaratto, L; Scaloni, A; Tell, G; Muro, A F

    2015-01-01

    Severe hyperbilirubinemia is toxic during central nervous system development. Prolonged and uncontrolled high levels of unconjugated bilirubin lead to bilirubin-induced encephalopathy and eventually death by kernicterus. Despite extensive studies, the molecular and cellular mechanisms of bilirubin toxicity are still poorly defined. To fill this gap, we investigated the molecular processes underlying neuronal injury in a mouse model of severe neonatal jaundice, which develops hyperbilirubinemia as a consequence of a null mutation in the Ugt1 gene. These mutant mice show cerebellar abnormalities and hypoplasia, neuronal cell death and die shortly after birth because of bilirubin neurotoxicity. To identify protein changes associated with bilirubin-induced cell death, we performed proteomic analysis of cerebella from Ugt1 mutant and wild-type mice. Proteomic data pointed-out to oxidoreductase activities or antioxidant processes as important intracellular mechanisms altered during bilirubin-induced neurotoxicity. In particular, they revealed that down-representation of DJ-1, superoxide dismutase, peroxiredoxins 2 and 6 was associated with hyperbilirubinemia in the cerebellum of mutant mice. Interestingly, the reduction in protein levels seems to result from post-translational mechanisms because we did not detect significant quantitative differences in the corresponding mRNAs. We also observed an increase in neuro-specific enolase 2 both in the cerebellum and in the serum of mutant mice, supporting its potential use as a biomarker of bilirubin-induced neurological damage. In conclusion, our data show that different protective mechanisms fail to contrast oxidative burst in bilirubin-affected brain regions, ultimately leading to neurodegeneration. PMID:25950469

  17. H2O2 pretreated rice seedlings specifically reduces arsenate not arsenite: difference in nutrient uptake and antioxidant defense response in a contrasting pair of rice cultivars.

    PubMed

    Mallick, Shekhar; Kumar, Navin; Sinha, Sarita; Dubey, Arvind Kumar; Tripathi, Rudra Deo; Srivastav, Vivek

    2014-10-01

    The study investigated the reduction in metalloid uptake at equimolar concentrations (~53.3 μM) of As(III) and As(V) in contrasting pair of rice seedlings by pretreating with H2O2 (1.0 μM) and SA (1.0 mM). Results obtained from the contrasting pair (arsenic tolerant vs. sensitive) of rice seedlings (cv. Pant Dhan 11 and MTU 7029, respectively) shows that pretreatment of H2O2 and H2O2 + SA reduces As(V) uptake significantly in both the cultivars, while no reduction in the As(III) uptake. The higher growth inhibition, higher H2O2 and TBARS content in sensitive cultivar against As(III) and As(V) treatments along with higher As accumulation (~1.2 mg g(-1) dw) than in cv. P11, unravels the fundamental difference in the response between the sensitive and tolerant cultivar. In the H2O2 pretreated plants, the translocation of As increased in tolerant cultivar against AsIII, whereas, it decreased in sensitive cultivar both against AsIII and AsV. In both the cultivars translocation of Mn increased in the H2O2 pretreated plants against As(III), whereas, the translocation of Cu increased against As(V). In tolerant cultivar the translocation of Fe increased against As(V) with H2O2 pretreatment whereas, it decreased in the sensitive cultivar. In both the cultivars, Zn translocation increased against As(III) and decreased against As(V). The higher level of H2O2 and SOD (EC 1.15.1.1) activity in sensitive cultivar whereas, higher, APX (EC 1.11.1.11), GR (EC 1.6.4.2) and GST (EC 1.6.4.2) activity in tolerant cultivar, also demonstrated the differential anti-oxidative defence responses between the contrasting rice cultivars.

  18. Deltamethrin-induced oxidative stress and biochemical changes in tissues and blood of catfish (Clarias gariepinus): antioxidant defense and role of alpha-tocopherol

    PubMed Central

    2012-01-01

    Background The pyrethroid class of insecticides, including deltamethrin, is being used as substitutes for organochlorines and organophosphates in pest-control programs because of their low environmental persistence and toxicity. This study was aimed to investigate the impact of commonly used pesticides (deltamethrin) on the blood and tissue oxidative stress level in catfish (Clarias gariepinus); in addition to the protective effect of α-tocopherol on deltamethrin induced oxidative stress. Catfish were divided into three groups, 1st control group include 20 fish divided into two tanks each one contain 10 fish, 2nd deltamethrin group, where Fish exposed to deltamethrin in a concentration (0.75 μg/l) and 3rd Vitamin E group, Fish exposed to deltamethrin and vitamin E at a dose of 12 μg/l for successive 4 days. Serum, liver, kidney and Gills were collected for biochemical assays. Tissue oxidative stress biomarkers malondialdhyde (MDA) and catalase activity in liver, kidney and gills tissues, serum liver enzymes (ALT and AST), serum albumin, total protein, urea and creatinine were analysed. Results Our results showed that 48 h. exposure to 0.75 μg/l deltamethrin significantly (p < 0.05) increased lipid peroxidation (MDA) in the liver, kidney and gills while catalase activity was significantly decreased in the same tissues. This accompanied by significant increase in serum ALT, AST activity, urea and creatinine and a marked decrease in serum albumin and total proteins. Conclusions It could be concluded that deltamethrin is highly toxic to catfish even in very low concentration (0.75 μg/l). Moreover the effect of deltamethrin was pronounced in the liver of catfish in comparison with kidneys and gills. Moreover fish antioxidants and oxidative stress could be used as biomarkers for aquatic pollution, thus helping in the diagnosis of pollution. Adminstration of 12 μg/l α-tocopherol restored the quantified tissue and serum parameters, so

  19. Epigallocatechin-3-gallate prevents lipid peroxidation and enhances antioxidant defense system via modulating hepatic nuclear transcription factors in heat-stressed quails.

    PubMed

    Sahin, K; Orhan, C; Tuzcu, M; Ali, S; Sahin, N; Hayirli, A

    2010-10-01

    Epigallocatechin-3-gallate (EGCG), a polyphenol derived from green tea, exerts antioxidant effects. Oxidative stress is one of the consequences of heat stress (HS), which also depresses performance in poultry. This experiment was conducted to elucidate the action mode of EGCG in alleviation of oxidative stress in heat-stressed quail (Coturnix coturnix japonica). A total of 180 five-week-old female Japanese quails were reared either at 22°C for 24 h/d (thermoneutral, TN) or 34°C for 8 h/d (HS) for 12 wk. Birds in both environments were randomly fed 1 of 3 diets: basal diet and basal diet added with 200 or 400 mg of EGCG/kg of diet. Each of the 2×3 factorially arranged groups was replicated in 10 cages, each containing 3 quails. Performance variables [feed intake (FI) and egg production (EP)], oxidative stress biomarkers [malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px)] and hepatic transcription factors [nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and nuclear factor (erythroid-derived 2)-like 2 (Nrf2)] were analyzed using 2-way ANOVA. Exposure to HS caused reductions in FI by 9.7% and EP by 14.4%, increased hepatic MDA level by 84.8%, and decreased hepatic SOD, CAT, and GSH-Px activities by 25.8, 52.3, and 45.5%, respectively (P<0.0001 for all). The hepatic NF-κB expression was greater (156 vs. 82%) and Nrf2 expression was lower (84 vs. 118%) for quails reared under the HS environment than for those reared under the TN environment (P<0.0001 for both). In response to increasing supplemental EGCG level, there were linear increases in FI from 29.6 to 30.9 g/d and EP from 84.3 to 90.1%/d, linear decreases in hepatic MDA level from 2.82 to 1.72 nmol/g and Nrf2 expression from 77.5 to 123.3%, and linear increases in hepatic SOD (146.4 to 182.2), CAT (36.2 to 47.1), and GSH-Px (13.5 to 18.5) activities (U/mg of protein) and NF-κB expression (149.7 to 87.3%) (P<0.0001 for all). Two

  20. Captopril and Valsartan May Improve Cognitive Function Through Potentiation of the Brain Antioxidant Defense System and Attenuation of Oxidative/Nitrosative Damage in STZ-Induced Dementia in Rat

    PubMed Central

    Arjmand Abbassi, Yasaman; Mohammadi, Mohammad Taghi; Sarami Foroshani, Mahsa; Raouf Sarshoori, Javad

    2016-01-01

    Purpose: Previous findings have shown the crucial roles of brain renin-angiotensin system (RAS) in pathogenesis of Alzheimer’s disease (AD). Since RAS inhibitors may have beneficial effects on dementia and cognitive function in elderly people, the aim of present study was to examine the neuroprotective actions of captopril and valsartan on memory function and neuronal damage in experimental model of AD. Methods: Adult forty male Wistar rats (220-280g) were randomly divided into 5 groups; Control, Vehicle, Alzheimer and treatment groups. AD was induced by the injections of streptozotocin (3mg/kg, bilateral intracerebroventricular) at days 1&3. Treated rats received orally captopril (50mg/kg/day) and valsartan (30mg/kg/day). Memory function and histological assessments were done at termination of experiment. Finally, superoxide dismutase (SOD) and catalase (CAT) activities as well as malondialdehyde (MDA) and NOx contents were determined. Results: There was a significant increase in the mean value of latency in Alzheimer group (66%). Captopril and valsartan considerably decreased this value in both treatment groups (45% and 72%, respectively). In Alzheimer group the activities of brain’s SOD and CAT reduced (40% and 47%, respectively) in accompany with an increase in MDA and NOx contents (49% and 50%, respectively). Captopril and valsartan significantly increased the activities of brain’s SOD and CAT concomitant reduction in MDA and NOx contents. Also, histopathological damages noticeably decreased in both treatment groups. Conclusion: Our findings indicate that RAS inhibition by using captopril and valsartan potentiates the antioxidant defense system of brain and reduces oxidative/nitrosative stress in accompany with neuronal damage during AD. PMID:28101460

  1. Monitoring antioxidant defenses and free radical production in space-flight, aviation and railway engine operators, for the prevention and treatment of oxidative stress, immunological impairment, and pre-mature cell aging.

    PubMed

    De Luca, C; Deeva, I; Mariani, S; Maiani, G; Stancato, A; Korkina, L

    2009-01-01

    Degenerative diseases, immune impairment, and premature ageing commonly affect professional categories exposed to severe environmental and psychological stress. Among these, cosmonauts routinely experience extreme conditions due to microgravity, space radiation, altered oxygen supply, physical and mental fatigue during training, spaceflight, and post-flight. Long route aviation pilots display elevated oncogenic risk, connected with cosmic radiation overexposure, and high mortality rates for cardiovascular causes. Engine drivers, like pilots, are affected by health consequences of psycho-emotional stress, and burnout syndrome. The free radical (FR)/antioxidant (AO) imbalance is a common feature in all these pathological conditions. To assess the effective relevance of oxidative stress, we analyzed blood and urine reliable markers of FR production and AO defenses in 12 Russian cosmonauts, 55 airline pilots, 63 train engine drivers, and 50 age-matched controls by measuring the following: (a) lipophilic/hydrophilic low-molecular weight AO and AO enzyme activities, (b) nitric oxide, superoxide anion, hydroperoxide production, and (c) urinary catecholamine/serotonine metabolites and lipoperoxidation markers. Cosmonauts showed elevated granulocyte superoxide and nitric oxide production, increased erythrocyte superoxide dismutase activity and glutathione oxidation, and drastically decreased plasma/leucocyte lipophilic AO levels (P < 0.001-0.01). Aviation pilots, like train drivers, displayed a mild but constant oxidative stress, more pronounced in intercontinental routes pilots, and consistent with lymphocyte chromosomal alterations, DNA oxidation, and cardiovascular malfunction. Results obtained on these selected professionals operating under wearing conditions offer a solid molecular basis for advising the regular monitoring of clinical biochemistry laboratory markers of AO/FR status, to tailor individually specific AO supplementation and diet regimen, and monitor

  2. COPD: balancing oxidants and antioxidants

    PubMed Central

    Fischer, Bernard M; Voynow, Judith A; Ghio, Andrew J

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) is one of the most common chronic illnesses in the world. The disease encompasses emphysema, chronic bronchitis, and small airway obstruction and can be caused by environmental exposures, primarily cigarette smoking. Since only a small subset of smokers develop COPD, it is believed that host factors interact with the environment to increase the propensity to develop disease. The major pathogenic factors causing disease include infection and inflammation, protease and antiprotease imbalance, and oxidative stress overwhelming antioxidant defenses. In this review, we will discuss the major environmental and host sources for oxidative stress; discuss how oxidative stress regulates chronic bronchitis; review the latest information on genetic predisposition to COPD, specifically focusing on oxidant/antioxidant imbalance; and review future antioxidant therapeutic options for COPD. The complexity of COPD will necessitate a multi-target therapeutic approach. It is likely that antioxidant supplementation and dietary antioxidants will have a place in these future combination therapies. PMID:25673984

  3. Transforming Defense

    DTIC Science & Technology

    2005-09-01

    or agency each week?” 47 By way of just one example, Madrid’s La Razon reported on September 13 , 2004, that Spain would lose U.S. bases to Portugal...public release, distribution unlimited 13 . SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...DEFENSE 7 responsibilities. The homeland security JOC envisions a layered and comprehensive defense requiring geographical and functional integra- tion. 13

  4. Lead Toxicity, Antioxidant Defense and Environment.

    PubMed

    Carocci, Alessia; Catalano, Alessia; Lauria, Graziantonio; Sinicropi, Maria Stefania; Genchi, Giuseppe

    Environmental and occupational exposure to a large number of chemicals occurs at various stages throughout human life. Many of these are devoid of toxicity, but some could pose a significant health risk, i.e. the exposure to environmental xenobiotic metals as lead, mercury (Sinicropi et al. 2010a; Carocci et al. 2014), cadmium, etc. In particular, lead has long been a widespread public concern (Basha and Reddy 2010). Lead is one of the earliest heavy metals discovered by men. Due to its unique properties, as low melting point, softness, malleability, ductility, and resistance to corrosion, men have used lead for the last 5000 years in a wide range of applications.

  5. Effects of xenobiotics on total antioxidant capacity

    PubMed Central

    2012-01-01

    The objective of this article was to review the effects of xenobiotics on total antioxidant capacity (TAC). Measurement of TAC is appropriate for evaluation of the total antioxidant defenses of blood, cells, and different kinds of tissues and organs. TAC is reduced by alcoholism, smoking, and exposure to radiation, herbicides, carbon monoxide, carbon tetrachloride, lead, arsenic, mercury, cadmium, aluminum, and other toxic elements. The test is also an important tool in evaluating environmental and occupational exposure. PMID:23554550

  6. Queuine promotes antioxidant defence system by activating cellular antioxidant enzyme activities in cancer.

    PubMed

    Pathak, Chandramani; Jaiswal, Yogesh K; Vinayak, Manjula

    2008-04-01

    Constant generation of Reactive oxygen species (ROS) during normal cellular metabolism of an organism is generally balanced by similar rate of consumption by antioxidants. Imbalance between ROS production and antioxidant defense results in increased level of ROS causing oxidative stress which leads to promotion of malignancy. Queuine is a hyper modified base analogue of guanine, found at first anti-codon position of Q- family of tRNAs. These tRNAs are completely modified with respect to queuosine in terminally differentiated somatic cells, however hypomodification of Q-tRNAs is close association with cell proliferation. Q-tRNA modification is essential for normal development, differentiation and cellular functions. Queuine is a nutrient factor to eukaryotes. It is found to promote cellular antioxidant defense system and inhibit tumorigenesis. The activities of antioxidant enzymes like catalase, SOD, glutathione peroxidase and glutathione reductase are found to be low in Dalton's lymphoma ascites transplanted (DLAT) mouse liver compared to normal. However, exogenous administration of queuine to DLAT mouse improves the activities of antioxidant enzymes. The results suggest that queuine promotes antioxidant defense system by increasing antioxidant enzyme activities and in turn inhibits oxidative stress and tumorigenesis.

  7. The antioxidant paradox in diabetes mellitus.

    PubMed

    Sheikh-Ali, Mae; Chehade, Joe M; Mooradian, Arshag D

    2011-05-01

    There is ample empiric evidence to indicate that oxidative stress contributes to the pathogenesis of coronary artery disease and has a key role in the onset and progression of diabetes and its complications. Diabetes leads to depletion of the cellular antioxidant defense system and is associated with an increase in the production of free radicals. Oxidative stress can be the result of multiple pathways. Some of these are related to substrate-driven overproduction of mitochondrial reactive oxygen species, advanced glycation end product formation, glucose autoxidation, and depletion of micronutrients and cellular elements with antioxidative properties. There are numerous observational studies in the literature showing a beneficial outcome of the consumption of antioxidant vitamins. However, the interventional trials portray a different picture. The divide between the robust experimental evidence of the pathogenetic role of increased oxidative load in diabetes and the overwhelming failure of antioxidants to show any health benefits in clinical trials may well be characterized as the "antioxidant paradox."

  8. Mitochondrial Targeted Antioxidant in Cerebral Ischemia.

    PubMed

    Ahmed, Ejaz; Donovan, Tucker; Yujiao, Lu; Zhang, Quanguang

    There has been much evidence suggesting that reactive oxygen species (ROS) generated in mitochondria during cerebral ischemia play a major role in programming the senescence of organism. Antioxidants dealing with mitochondria slow down the appearance and progression of symptoms in cerebral ischemia and increase the life span of organisms. The mechanisms of mitochondrial targeted antioxidants, such as SKQ1, Coenzyme Q10, MitoQ, and Methylene blue, include increasing adenosine triphosphate (ATP) production, decreasing production of ROS and increasing antioxidant defenses, providing benefits in neuroprotection following cerebral ischemia. A number of studies have shown the neuroprotective role of these mitochondrial targeted antioxidants in cerebral ischemia. Here in this short review we have compiled the literature supporting consequences of mitochondrial dysfunction, and the protective role of mitochondrial targeted antioxidants.

  9. An Abscisic Acid-Independent Oxylipin Pathway Controls Stomatal Closure and Immune Defense in Arabidopsis

    PubMed Central

    Mondy, Samuel; Tranchimand, Sylvain; Rumeau, Dominique; Boudsocq, Marie; Garcia, Ana Victoria; Douki, Thierry; Bigeard, Jean; Laurière, Christiane; Chevalier, Anne; Castresana, Carmen; Hirt, Heribert

    2013-01-01

    Plant stomata function in innate immunity against bacterial invasion and abscisic acid (ABA) has been suggested to regulate this process. Using genetic, biochemical, and pharmacological approaches, we demonstrate that (i) the Arabidopsis thaliana nine-specific-lipoxygenase encoding gene, LOX1, which is expressed in guard cells, is required to trigger stomatal closure in response to both bacteria and the pathogen-associated molecular pattern flagellin peptide flg22; (ii) LOX1 participates in stomatal defense; (iii) polyunsaturated fatty acids, the LOX substrates, trigger stomatal closure; (iv) the LOX products, fatty acid hydroperoxides, or reactive electrophile oxylipins induce stomatal closure; and (v) the flg22-mediated stomatal closure is conveyed by both LOX1 and the mitogen-activated protein kinases MPK3 and MPK6 and involves salicylic acid whereas the ABA-induced process depends on the protein kinases OST1, MPK9, or MPK12. Finally, we show that the oxylipin and the ABA pathways converge at the level of the anion channel SLAC1 to regulate stomatal closure. Collectively, our results demonstrate that early biotic signaling in guard cells is an ABA-independent process revealing a novel function of LOX1-dependent stomatal pathway in plant immunity. PMID:23526882

  10. Antioxidant action of Andrographis paniculata on lymphoma.

    PubMed

    Verma, Nibha; Vinayak, Manjula

    2008-12-01

    Regulation of the balance between production of reactive oxygen species (ROS) by cellular processes and its removal by antioxidant defense system maintains normal physiological processes. Any condition leading to increased ROS results in oxidative stress which has been related with a number of diseases including cancer. Improvement in antioxidant defense system is required to overcome the damaging effects of oxidative stress. Therefore in the present study, effect of the aqueous extract of a medicinal plant Andrographis paniculata (AP) on antioxidant defense system in liver is investigated in lymphoma bearing AKR mice. Estimating catalase, superoxide dismutase and glutathione S transferase monitored the antioxidant action. Oral administration of the aqueous extract of A. paniculata in different doses causes a significant elevation of catalase, superoxide dismutase and glutathione S transferase activities. It reveals the antioxidant action of the aqueous extract of AP, which may play a role in the anticarcinogenic activity by reducing the oxidative stress. LDH activity is known to increase in various cancers due to hypoxic condition. Lactate dehydrogenase is used as tumor marker. We find a significant decrease in LDH activity on treatment with AP, which indicates a decrease in carcinogenic activity. A comparison with Doxorubicin (DOX), an anticancerous drug, indicates that the aqueous extract of AP is more effective than DOX with respect to its effect on catalase, superoxide dismutase, glutathione S transferase as well as on lactate dehydrogenase activities in liver of lymphoma bearing mice.

  11. Antioxidant responses of wheat plants under stress

    PubMed Central

    Caverzan, Andréia; Casassola, Alice; Brammer, Sandra Patussi

    2016-01-01

    Abstract Currently, food security depends on the increased production of cereals such as wheat (Triticum aestivum L.), which is an important source of calories and protein for humans. However, cells of the crop have suffered from the accumulation of reactive oxygen species (ROS), which can cause severe oxidative damage to the plants, due to environmental stresses. ROS are toxic molecules found in various subcellular compartments. The equilibrium between the production and detoxification of ROS is sustained by enzymatic and nonenzymatic antioxidants. In the present review, we offer a brief summary of antioxidant defense and hydrogen peroxide (H2O2) signaling in wheat plants. Wheat plants increase antioxidant defense mechanisms under abiotic stresses, such as drought, cold, heat, salinity and UV-B radiation, to alleviate oxidative damage. Moreover, H2O2 signaling is an important factor contributing to stress tolerance in cereals. PMID:27007891

  12. Human bronchial epithelial cells exposed in vitro to diesel exhaust particles exhibit alterations in cell rheology and cytotoxicity associated with decrease in antioxidant defenses and imbalance in pro- and anti-apoptotic gene expression.

    PubMed

    Seriani, Robson; de Souza, Claudia Emanuele Carvalho; Krempel, Paloma Gava; Frias, Daniela Perroni; Matsuda, Monique; Correia, Aristides Tadeu; Ferreira, Márcia Zotti Justo; Alencar, Adriano Mesquita; Negri, Elnara Marcia; Saldiva, Paulo Hilário Nascimento; Mauad, Thais; Macchione, Mariangela

    2016-05-01

    Diesel exhaust particles (DEPs) from diesel engines produce adverse alterations in cells of the airways by activating intracellular signaling pathways and apoptotic gene overexpression, and also by influencing metabolism and cytoskeleton changes. This study used human bronchial epithelium cells (BEAS-2B) in culture and evaluates their exposure to DEPs (15ug/mL for 1 and 2 h) in order to determine changes to cell rheology (viscoelasticity) and gene expression of the enzymes involved in oxidative stress, apoptosis, and cytotoxicity. BEAS-2B cells exposed to DEPs were found to have a significant loss in stiffness, membrane stability, and mitochondrial activity. The genes involved in apoptosis [B cell lymphoma 2 (BCL-2 and caspase-3)] presented inversely proportional expressions (p = 0.05, p = 0.01, respectively), low expression of the genes involved in antioxidant responses [SOD1 (superoxide dismutase 1); SOD2 (superoxide dismutase 2), and GPx (glutathione peroxidase) (p = 0.01)], along with an increase in cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) (p = 0.01). These results suggest that alterations in cell rheology and cytotoxicity could be associated with oxidative stress and imbalance between pro- and anti-apoptotic genes.

  13. Understanding Defense Mechanisms.

    PubMed

    Cramer, Phebe

    2015-12-01

    Understanding defense mechanisms is an important part of psychotherapy. In this article, we trace the history of the concept of defense, from its origin with Freud to current views. The issue of defense as an unconscious mechanism is examined. The question of whether defenses are pathological, as well as their relation to pathology, is discussed. The effect of psychotherapy on the use of defenses, and their relation to a therapeutic alliance is explored. A series of empirical research studies that demonstrate the functioning of defense mechanisms and that support the theory is presented. Research also shows that as part of normal development, different defenses emerge at different developmental periods, and that gender differences in defense use occur.

  14. Defense Spending and Reform

    DTIC Science & Technology

    2012-04-02

    Background paper on SIPRI military expenditure data Public Notice, “ Spending and Defending Defense spending has become a highly......Budget; Finance Reform; Military Spending ; Defense Spending ; Budget Cuts 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

  15. Recognizing Plant Defense Priming.

    PubMed

    Martinez-Medina, Ainhoa; Flors, Victor; Heil, Martin; Mauch-Mani, Brigitte; Pieterse, Corné M J; Pozo, Maria J; Ton, Jurriaan; van Dam, Nicole M; Conrath, Uwe

    2016-10-01

    Defense priming conditions diverse plant species for the superinduction of defense, often resulting in enhanced pest and disease resistance and abiotic stress tolerance. Here, we propose a guideline that might assist the plant research community in a consistent assessment of defense priming in plants.

  16. Radiological Defense. Textbook.

    ERIC Educational Resources Information Center

    Defense Civil Preparedness Agency (DOD), Washington, DC.

    This textbook has been prepared under the direction of the Defense Civil Preparedness Agency (DCPA) Staff College for use as a student reference manual in radiological defense (RADEF) courses. It provides much of the basic technical information necessary for a proper understanding of radiological defense and summarizes RADEF planning and expected…

  17. Comparison of physiological and antioxidant responses of Anoda cristata and cotton to progressive drought

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Simultaneous investigation of variables related to gas exchange, photochemistry and antioxidant defenses during water stress is crucial for understanding stress tolerance mechanisms and consequent success of both economically important plant species and their interfering counterparts. This study ev...

  18. Oxidative stress and antioxidants: Distress or eustress?

    PubMed

    Niki, Etsuo

    2016-04-01

    There is a growing consensus that reactive oxygen species (ROS) are not just associated with various pathologies, but that they act as physiological redox signaling messenger with important regulatory functions. It is sometimes stated that "if ROS is a physiological signaling messenger, then removal of ROS by antioxidants such as vitamins E and C may not be good for human health." However, it should be noted that ROS acting as physiological signaling messenger and ROS removed by antioxidants are not the same. The lipid peroxidation products of polyunsaturated fatty acids and cholesterol induce adaptive response and enhance defense capacity against subsequent oxidative insults, but it is unlikely that these lipid peroxidation products are physiological signaling messenger produced on purpose. The removal of ROS and inhibition of lipid peroxidation by antioxidants should be beneficial for human health, although it has to be noted also that they may not be an effective inhibitor of oxidative damage mediated by non-radical oxidants. The term ROS is vague and, as there are many ROS and antioxidants which are different in chemistry, it is imperative to explicitly specify ROS and antioxidant to understand the effects and role of oxidative stress and antioxidants properly.

  19. Quadrennial Defense Review Report

    DTIC Science & Technology

    2010-02-01

    Roles of Military Power 9  U.S. Defense Objectives 11  REBALANCING THE FORCE 17  Defend the United States and Support Civil Authorities at Home 18...the need to plan for the broadest possible range of operations—from homeland defense and defense support to civil authorities, to deterrence and...Defend the United States and support civil authorities at home: The rapid proliferation of destructive technologies, combined with potent

  20. 22 CFR 130.4 - Defense articles and defense services.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Defense articles and defense services. 130.4 Section 130.4 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS POLITICAL CONTRIBUTIONS, FEES AND COMMISSIONS § 130.4 Defense articles and defense services. Defense articles and...

  1. 22 CFR 130.4 - Defense articles and defense services.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Defense articles and defense services. 130.4 Section 130.4 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS POLITICAL CONTRIBUTIONS, FEES AND COMMISSIONS § 130.4 Defense articles and defense services. Defense articles and...

  2. 22 CFR 130.4 - Defense articles and defense services.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Defense articles and defense services. 130.4 Section 130.4 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS POLITICAL CONTRIBUTIONS, FEES AND COMMISSIONS § 130.4 Defense articles and defense services. Defense articles and...

  3. 22 CFR 130.4 - Defense articles and defense services.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Defense articles and defense services. 130.4 Section 130.4 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS POLITICAL CONTRIBUTIONS, FEES AND COMMISSIONS § 130.4 Defense articles and defense services. Defense articles and...

  4. 22 CFR 130.4 - Defense articles and defense services.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Defense articles and defense services. 130.4 Section 130.4 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS POLITICAL CONTRIBUTIONS, FEES AND COMMISSIONS § 130.4 Defense articles and defense services. Defense articles and...

  5. Dynamic defense workshop :

    SciTech Connect

    Crosby, Sean Michael; Doak, Justin E.; Haas, Jason Juedes.; Helinski, Ryan; Lamb, Christopher C.

    2013-02-01

    On September 5th and 6th, 2012, the Dynamic Defense Workshop: From Research to Practice brought together researchers from academia, industry, and Sandia with the goals of increasing collaboration between Sandia National Laboratories and external organizations, de ning and un- derstanding dynamic, or moving target, defense concepts and directions, and gaining a greater understanding of the state of the art for dynamic defense. Through the workshop, we broadened and re ned our de nition and understanding, identi ed new approaches to inherent challenges, and de ned principles of dynamic defense. Half of the workshop was devoted to presentations of current state-of-the-art work. Presentation topics included areas such as the failure of current defenses, threats, techniques, goals of dynamic defense, theory, foundations of dynamic defense, future directions and open research questions related to dynamic defense. The remainder of the workshop was discussion, which was broken down into sessions on de ning challenges, applications to host or mobile environments, applications to enterprise network environments, exploring research and operational taxonomies, and determining how to apply scienti c rigor to and investigating the eld of dynamic defense.

  6. Technologies for Distributed Defense

    SciTech Connect

    Seiders, Barbara AB; Rybka, Anthony J.

    2002-07-01

    For Americans, the nature of warfare changed on September 11, 2001. Our national security henceforth will require distributed defense. One extreme of distributed defense is represented by fully deployed military troops responding to a threat from a hostile nation state. At the other extreme is a country of "citizen soldiers," with families and communities securing their common defense through heightened awareness, engagement as good neighbors, and local support of and cooperation with local law enforcement, emergency and health care providers. Technologies - for information exploitation, biological agent detection, health care surveillance, and security - will be critical to ensuring success in distributed defense.

  7. Technologies for distributed defense

    NASA Astrophysics Data System (ADS)

    Seiders, Barbara; Rybka, Anthony

    2002-07-01

    For Americans, the nature of warfare changed on September 11, 2001. Our national security henceforth will require distributed defense. One extreme of distributed defense is represented by fully deployed military troops responding to a threat from a hostile nation state. At the other extreme is a country of 'citizen soldiers', with families and communities securing their common defense through heightened awareness, engagement as good neighbors, and local support of and cooperation with local law enforcement, emergency and health care providers. Technologies - for information exploitation, biological agent detection, health care surveillance, and security - will be critical to ensuring success in distributed defense.

  8. Studies on oxidants and antioxidants with a brief glance at their relevance to the immune system.

    PubMed

    Amir Aslani, Banafsheh; Ghobadi, Sirous

    2016-02-01

    Free radical generation occurs continuously within cells as a consequence of common metabolic processes. However, in high concentrations, whether from endogenous or exogenous sources, free radicals can lead to oxidative stress; a harmful process that cause serious damages to all biomolecules in our body hence impairs cell functions and even results in cell death and diseased states. Oxidative injuries accumulate over time and participate in cancer development, cardiovascular and neurodegenerative disorders as well as aging. Nature has bestowed the human body with a complex web of antioxidant defense system including enzymatic antioxidants like glutathione peroxidase and glutathione reductase, catalase and superoxide dismutase as well as non-enzymatic antioxidants such as thiol antioxidants, melatonin, coenzyme Q, and metal chelating proteins, which are efficient enough to fight against excessive free radicals. Also, nutrient antioxidants such as vitamin C, vitamin E, carotenoids, polyphenols, and trace elements are known to have high antioxidant potency to assist in minimizing harmful effects of reactive species. The immune system is also extremely vulnerable to oxidant and antioxidant balance as uncontrolled free radical production can impair its function and defense mechanism. The present paper reviews the ways by which free radicals form in the body and promote tissue damage, as well as the role of the antioxidants defense mechanisms. Finally, we will have a brief glance at oxidants and antioxidants relevance to the immune system.

  9. The Role of Antioxidants in Skin Cancer Prevention and Treatment

    PubMed Central

    Poljšak, Borut; Adamic, Metka

    2014-01-01

    Skin cells are constantly exposed to reactive oxygen species (ROS) and oxidative stress from exogenous and endogenous sources. UV radiation is the most important environmental factor in the development of skin cancer and skin aging. The primary products caused by UV exposure are generally direct DNA oxidation or generation of free radicals which form and decompose extremely quickly but can produce effects that can last for hours, days, or even years. UV-induced generation of ROS in the skin develops oxidative stress when their formation exceeds the antioxidant defense ability. The reduction of oxidative stress can be achieved on two levels: by lowering exposure to UVR and/or by increasing levels of antioxidant defense in order to scavenge ROS. The only endogenous protection of our skin is melanin and enzymatic antioxidants. Melanin, the pigment deposited by melanocytes, is the first line of defense against DNA damage at the surface of the skin, but it cannot totally prevent skin damage. A second category of defense is repair processes, which remove the damaged biomolecules before they can accumulate and before their presence results in altered cell metabolism. Additional UV protection includes avoidance of sun exposure, usage of sunscreens, protective clothes, and antioxidant supplements. PMID:24790705

  10. The role of antioxidants in skin cancer prevention and treatment.

    PubMed

    Godic, Aleksandar; Poljšak, Borut; Adamic, Metka; Dahmane, Raja

    2014-01-01

    Skin cells are constantly exposed to reactive oxygen species (ROS) and oxidative stress from exogenous and endogenous sources. UV radiation is the most important environmental factor in the development of skin cancer and skin aging. The primary products caused by UV exposure are generally direct DNA oxidation or generation of free radicals which form and decompose extremely quickly but can produce effects that can last for hours, days, or even years. UV-induced generation of ROS in the skin develops oxidative stress when their formation exceeds the antioxidant defense ability. The reduction of oxidative stress can be achieved on two levels: by lowering exposure to UVR and/or by increasing levels of antioxidant defense in order to scavenge ROS. The only endogenous protection of our skin is melanin and enzymatic antioxidants. Melanin, the pigment deposited by melanocytes, is the first line of defense against DNA damage at the surface of the skin, but it cannot totally prevent skin damage. A second category of defense is repair processes, which remove the damaged biomolecules before they can accumulate and before their presence results in altered cell metabolism. Additional UV protection includes avoidance of sun exposure, usage of sunscreens, protective clothes, and antioxidant supplements.

  11. Defense Science Board Task Force Report on Cyber Defense Management

    DTIC Science & Technology

    2016-09-01

    DSB Task Force Report on Cyber Defense Management September 2016 (U) This page intentionally blank REPORT OF THE DEFENSE SCIENCE BOARD STUDY ON Cyber...U) This report is a product of the Defense Science Board (DSB). (U) The DSB is a Federal Advisory Committee established to provide independent...position of the Department of Defense (DoD). The Defense Science Board Study on Cyber Defense completed its information-gathering in November 2015. The

  12. Schools and Civil Defense.

    ERIC Educational Resources Information Center

    Office of Civil Defense (DOD), Washington, DC.

    Civil defense is a planned, coordinated action to protect the population during any emergency whether arising from thermonuclear attack or natural disaster. The Federal Government has assumed four responsibilities--(1) to keep track of the nature of the threat which the civil defense program must meet, (2) to prepare and disseminate information…

  13. Defense Mechanisms: A Bibliography.

    ERIC Educational Resources Information Center

    Pedrini, D. T.; Pedrini, Bonnie C.

    This bibliography includes studies of defense mechanisms, in general, and studies of multiple mechanisms. Defense mechanisms, briefly and simply defined, are the unconscious ego defendants against unpleasure, threat, or anxiety. Sigmund Freud deserves the clinical credit for studying many mechanisms and introducing them in professional literature.…

  14. Herbal antioxidant in clinical practice: A review

    PubMed Central

    Alok, Shashi; Jain, Sanjay Kumar; Verma, Amita; Kumar, Mayank; Mahor, Alok; Sabharwal, Monika

    2014-01-01

    Antioxidant-the word itself is magic. Using the antioxidant concept as a spearhead in proposed mechanisms for staving off so-called "free-radical" reactions, the rush is on to mine claims for the latest and most effective combination of free-radical scavenging compounds. We must acknowledge that such "radicals" have definitively been shown to damage all biochemical components such as DNA/RNA, carbohydrates, unsaturated lipids, proteins, and micronutrients such as carotenoids (alpha and beta carotene, lycopene), vitamins A, B6, B12, and folate. Defense strategies against such aggressive radical species include enzymes, antioxidants that occur naturally in the body (glutathione, uric acid, ubiquinol-10, and others) and radical scavenging nutrients, such as vitamins A, C, and E, and carotenoids. This paper will present a brief discussion of some well- and little-known herbs that may add to the optimization of antioxidant status and therefore offer added preventive values for overall health. It is important to state at the outset that antioxidants vary widely in their free-radical quenching effects and each may be individually attracted to specific cell sites. Further evidence of the specialized nature of the carotenoids is demonstrated by the appearance of two carotenoids in the macula region of the retina where beta-carotene is totally absent. PMID:24144136

  15. Antioxidant therapy in human endocrine disorders.

    PubMed

    Golbidi, Saeid; Laher, Ismail

    2010-01-01

    Reactive oxygen species (ROS) have deleterious or beneficial effects; this dual nature of ROS means that ROS act as intracellular signaling molecules and as defense mechanisms against micro-organisms. An overproduction of ROS results in oxidative stress, a deleterious process that damages cell structures, including lipids, proteins, and DNA. Oxidative stress plays a major role in various human disease states, including endocrine dysfunction. As a safeguard against oxidative stress, several endogenous nonenzymatic and enzymatic antioxidant systems exist. Antioxidants can delay or prevent oxidative stress and are widely used in the hope of maintaining health and preventing diseases. Although early studies suggested that antioxidant supplements promoted health, later clinical trials revealed that it may not be true in all cases. In this article, we provide a brief review of the pathophysiologic aspects of oxidative stress in a number of the most commonly human endocrionopathies (diabetes, male and female infertility and thyroid diseases) and review the therapeutic potentials of existing antioxidant strategies. We focus on human clinical trials and discuss the implications of their results. Based on the data reported so far, we conclude that the results reported challenge us to design better antioxidant trials in future, with a particular emphasis on identifying 1) appropriate doses 2) selecting the right populations 3) treating for optimal durations and 4) specific intracellular targeting mechanisms.

  16. Oxidative and antioxidant status in plasma of runners: effect of oral supplementation with natural antioxidants.

    PubMed

    Di Giacomo, Claudia; Acquaviva, Rosaria; Sorrenti, Valeria; Vanella, Angelo; Grasso, Salvatore; Barcellona, Maria Luisa; Galvano, Fabio; Vanella, Luca; Renis, Marcella

    2009-02-01

    Aerobic exercise increases free radical production as a consequence of enhanced oxygen consumption. If free radical formation exceeds antioxidant capacity, lipids, proteins, and DNA may be oxidized. Oxidative stress is widely recognized as a factor in many degenerative human diseases. The role of dietary antioxidants in protection against disease is a topic of continuing interest. In fact, there is epidemiological evidence correlating a higher intake of nutrients possessing antioxidant abilities with a lower incidence of various human diseases. This study was directed at investigating whether changes in plasma antioxidant capacity and oxidative stress markers occur in voluntary wheel runners, before and after oral supplementation with lycopene and isoflavones. For this purpose, plasma antioxidant capacity and oxidative stress markers were assessed in long distance runners at the end of a 60-minute run. Comparisons were made between runners before and after 60 days of supplementation with lycopene and isoflavones. DNA damage in blood cells of the same samples was also evaluated by comet assay. This investigation shows that oral supplementation with lycopene and soy-derived isoflavones significantly reduced lipid peroxidation and enhanced plasma nonproteic antioxidant defense.

  17. Aspergillus flavus impairs antioxidative enzymes of Sternochetus mangiferae during mycosis.

    PubMed

    Jayanthi, Kamala P D; Ayyasamy, Arthikirubha; Kempraj, Vivek; Aurade, Ravindra M; Govindan, Selvakumar; Verghese, Abraham

    2015-01-01

    Insects depend upon cuticular, humoral and cellular defenses to resist mycosis. However, entomopathogenic fungi through co-evolution have developed mechanisms to counter such defenses. Although a plethora of mechanisms of mycosis by entomopathogenic fungi are well-established, studies on the impairment of insects' antioxidative enzymes during mycosis remain elusive. Here, we used the interaction of Sternochetus mangiferae and its associated entomopathogenic fungus, Aspergillus flavus, as a model to validate our hypothesis. Uninfected insects were exposed to fungal spores for infection to occur. We observed symptoms of mycosis within 48 h of incubation period. Biochemical studies on antioxidative enzymes namely catalase, peroxidase and phenoloxidase, in infected and uninfected insects revealed decreased activity of these enzymes. It appears that A. flavus disables the host's antioxidative enzyme system that plays a crucial role in elimination of oxidative toxins produced during mycosis.

  18. Maximizing Antioxidants in Fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fruits contain high levels of antioxidant compounds, such as carotenoids, flavonoids, vitamins, and phenols. These antioxidants are capable of performing a number of functions including free radical scavengers, peroxide decomposers, singlet and triplet oxygen quenchers, enzyme inhibitors, and synerg...

  19. Maximizing Antioxidants in Fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fruits contain high levels of antioxidant compounds, such as carotenoids, flavonoids, vitamins, and phenols. These antioxidants are capable of performing a number of functions including free radical scavengers, peroxide decomposers, singlet and triplet oxygen quenchers, enzyme inhibitors, and syner...

  20. The 1987 defense budget

    SciTech Connect

    Epstein, J.M.

    1986-01-01

    The Brookings annual analysis of the defense budget is designed to identify critical national security issues facing the country, to clarify choices that must be made in allocating resources, and to encourage informed public debate. This volume examines the Reagan administration's 1987 budget and associated multi-year plan for defense. It is also part of a long-range effort at Brookings to use dynamic campaign analysis to address more explicitly and in greater detail the full scope of force planning and defense budgeting issues.

  1. The 1988 defense budget

    SciTech Connect

    Epstein, J.M.

    1987-01-01

    The Brookings annual analysis of the defense budget is designed to identify critical national security issues facing the country, to clarify choices that must be made in allocating resources, and to encourage informed public debate. Like its predecessors, this volume critically examines the Reagan administration's 1988 budget and associated multi-year plan for defense. It is part of a long-range effort at Brookings to use dynamic campaign analysis to address more explicitly and in greater detail the full scope of force planning and defense budgeting issues.

  2. α-Tocopherol prevents lymphoma by improving antioxidant defence system of mice.

    PubMed

    Sharma, Renu; Vinayak, Manjula

    2013-02-01

    Increased level of ROS causes oxidative stress and leads to various pathological conditions including cancer. Therefore antioxidants should contribute to cancer prevention by improving antioxidant defense system and thereby protecting the cell from oxidative damage. In the present study we have validated the hypothesis by evaluating the antioxidant action of α-tocopherol. The effect of α-tocopherol is analyzed on oxidative stress as well as its regulation on antioxidant defense system. Oxidative stress is measured in terms of reduced glutathione and protein carbonylation. To evaluate the role of α-tocopherol on antioxidant defense system, the activities and expressions of antioxidant enzymes like glutathione peroxidase, catalase and superoxide dismutase are analyzed by activity gel assay and by RT-PCR respectively. These enzyme activities and/or expressions are found to be improved by α-tocopherol in lymphoma bearing mice which brings down the oxidative stress as reflected by increased level of reduced glutathione as well as decreased protein carbonylation. The effect of α-tocopherol is further analyzed on general characteristics of lymphoma growth like body weight, longevity, accumulation of ascites fluid, angiogenesis in peritoneum, morphology of liver and abundance of lymphocytes. The antioxidant α-tocopherol is found to check lymphoma growth. The results suggest that α-tocopherol contributes to lymphoma prevention by improving antioxidant defence system of mice.

  3. Antioxidant role of zinc in diabetes mellitus.

    PubMed

    Cruz, Kyria Jayanne Clímaco; de Oliveira, Ana Raquel Soares; Marreiro, Dilina do Nascimento

    2015-03-15

    Chronic hyperglycemia statue noticed in diabetes mellitus favors the manifestation of oxidative stress by increasing the production of reactive oxygen species and/or by reducing the antioxidant defense system activity. Zinc plays an important role in antioxidant defense in type 2 diabetic patients by notably acting as a cofactor of the superoxide dismutase enzyme, by modulating the glutathione metabolism and metallothionein expression, by competing with iron and copper in the cell membrane and by inhibiting nicotinamide adenine dinucleotide phosphate-oxidase enzyme. Zinc also improves the oxidative stress in these patients by reducing chronic hyperglycemia. It indeed promotes phosphorylation of insulin receptors by enhancing transport of glucose into cells. However, several studies reveal changes in zinc metabolism in individuals with type 2 diabetes mellitus and controversies remain regarding the effect of zinc supplementation in the improvement of oxidative stress in these patients. Faced with the serious challenge of the metabolic disorders related to oxidative stress in diabetes along with the importance of antioxidant nutrients in the control of this disease, new studies may contribute to improve our understanding of the role played by zinc against oxidative stress and its connection with type 2 diabetes mellitus prognosis. This could serve as a prelude to the development of prevention strategies and treatment of disorders associated with this chronic disease.

  4. Antioxidants in liver health

    PubMed Central

    Casas-Grajales, Sael; Muriel, Pablo

    2015-01-01

    Liver diseases are a worldwide medical problem because the liver is the principal detoxifying organ and maintains metabolic homeostasis. The liver metabolizes various compounds that produce free radicals (FR). However, antioxidants scavenge FR and maintain the oxidative/antioxidative balance in the liver. When the liver oxidative/antioxidative balance is disrupted, the state is termed oxidative stress. Oxidative stress leads to deleterious processes in the liver and produces liver diseases. Therefore, restoring antioxidants is essential to maintain homeostasis. One method of restoring antioxidants is to consume natural compounds with antioxidant capacity. The objective of this review is to provide information pertaining to various antioxidants found in food that have demonstrated utility in improving liver diseases. PMID:26261734

  5. DEFENSE INDUSTRY PROFIT REVIEW

    DTIC Science & Technology

    The Department of Defense (DoD) must employ contracting policies and methods that create an environment for profit opportunities. Just where the... profit range should fall is a matter of judgment and a point on which there probably will always be disagreement. This report is intended to serve as a...partial basis for DoD management’s assessment of the adequacy of defense business profits , as part of their continuing evaluation of contracting policies and methods.

  6. 75 FR 76423 - Defense Intelligence Agency National Defense Intelligence College Board of Visitors Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... of the Secretary Defense Intelligence Agency National Defense Intelligence College Board of Visitors Closed Meeting AGENCY: National Defense Intelligence College, Defense Intelligence Agency, Department of... a closed meeting of the Defense Intelligence Agency National Defense Intelligence College Board...

  7. 76 FR 28960 - Defense Intelligence Agency National Defense Intelligence College Board of Visitors Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-19

    ... of the Secretary Defense Intelligence Agency National Defense Intelligence College Board of Visitors Closed Meeting AGENCY: National Defense Intelligence College, Defense Intelligence Agency, Department of... a closed meeting of the Defense Intelligence Agency National Defense Intelligence College Board...

  8. A genetic screen reveals Arabidopsis stomatal and/or apoplastic defenses against Pseudomonas syringae pv. tomato DC3000.

    PubMed

    Zeng, Weiqing; Brutus, Alexandre; Kremer, James M; Withers, John C; Gao, Xiaoli; Jones, A Daniel; He, Sheng Yang

    2011-10-01

    Bacterial infection of plants often begins with colonization of the plant surface, followed by entry into the plant through wounds and natural openings (such as stomata), multiplication in the intercellular space (apoplast) of the infected tissues, and dissemination of bacteria to other plants. Historically, most studies assess bacterial infection based on final outcomes of disease and/or pathogen growth using whole infected tissues; few studies have genetically distinguished the contribution of different host cell types in response to an infection. The phytotoxin coronatine (COR) is produced by several pathovars of Pseudomonas syringae. COR-deficient mutants of P. s. tomato (Pst) DC3000 are severely compromised in virulence, especially when inoculated onto the plant surface. We report here a genetic screen to identify Arabidopsis mutants that could rescue the virulence of COR-deficient mutant bacteria. Among the susceptible to coronatine-deficient Pst DC3000 (scord) mutants were two that were defective in stomatal closure response, two that were defective in apoplast defense, and four that were defective in both stomatal and apoplast defense. Isolation of these three classes of mutants suggests that stomatal and apoplastic defenses are integrated in plants, but are genetically separable, and that COR is important for Pst DC3000 to overcome both stomatal guard cell- and apoplastic mesophyll cell-based defenses. Of the six mutants defective in bacterium-triggered stomatal closure, three are defective in salicylic acid (SA)-induced stomatal closure, but exhibit normal stomatal closure in response to abscisic acid (ABA), and scord7 is compromised in both SA- and ABA-induced stomatal closure. We have cloned SCORD3, which is required for salicylic acid (SA) biosynthesis, and SCORD5, which encodes an ATP-binding cassette (ABC) protein, AtGCN20/AtABCF3, predicted to be involved in stress-associated protein translation control. Identification of SCORD5 begins to implicate

  9. National Missile Defense Contingency Deployment.

    DTIC Science & Technology

    1995-01-01

    Defense Organization PMCS IDEA PAPER TITLE: National Missile Defense, Contingency Deployment Planning PMCS CLASS: 95C AUTHOR: Clifford E. Reeves... NATIONAL MISSILE DEFENSE CONTINGENCY DEPLOYMENT INTRODUCTION The author feels it is vital to start strategic planning for the development of operational...PROFESSIONAL MILITARY COMPTROLLER SCHOOL IDEA PAPER TITLE NATIONAL MISSILE DEFENSE CONTINGENCY DEPLOYMENT AUTHOR CLIFFORD E. REEVES GS-15, OSD

  10. Future Climate CO2 Levels Mitigate Stress Impact on Plants: Increased Defense or Decreased Challenge?

    PubMed

    AbdElgawad, Hamada; Zinta, Gaurav; Beemster, Gerrit T S; Janssens, Ivan A; Asard, Han

    2016-01-01

    Elevated atmospheric CO2 can stimulate plant growth by providing additional C (fertilization effect), and is observed to mitigate abiotic stress impact. Although, the mechanisms underlying the stress mitigating effect are not yet clear, increased antioxidant defenses, have been held primarily responsible (antioxidant hypothesis). A systematic literature analysis, including "all" papers [Web of Science (WoS)-cited], addressing elevated CO2 effects on abiotic stress responses and antioxidants (105 papers), confirms the frequent occurrence of the stress mitigation effect. However, it also demonstrates that, in stress conditions, elevated CO2 is reported to increase antioxidants, only in about 22% of the observations (e.g., for polyphenols, peroxidases, superoxide dismutase, monodehydroascorbate reductase). In most observations, under stress and elevated CO2 the levels of key antioxidants and antioxidant enzymes are reported to remain unchanged (50%, e.g., ascorbate peroxidase, catalase, ascorbate), or even decreased (28%, e.g., glutathione peroxidase). Moreover, increases in antioxidants are not specific for a species group, growth facility, or stress type. It seems therefore unlikely that increased antioxidant defense is the major mechanism underlying CO2-mediated stress impact mitigation. Alternative processes, probably decreasing the oxidative challenge by reducing ROS production (e.g., photorespiration), are therefore likely to play important roles in elevated CO2 (relaxation hypothesis). Such parameters are however rarely investigated in connection with abiotic stress relief. Understanding the effect of elevated CO2 on plant growth and stress responses is imperative to understand the impact of climate changes on plant productivity.

  11. Future Climate CO2 Levels Mitigate Stress Impact on Plants: Increased Defense or Decreased Challenge?

    PubMed Central

    AbdElgawad, Hamada; Zinta, Gaurav; Beemster, Gerrit T. S.; Janssens, Ivan A.; Asard, Han

    2016-01-01

    Elevated atmospheric CO2 can stimulate plant growth by providing additional C (fertilization effect), and is observed to mitigate abiotic stress impact. Although, the mechanisms underlying the stress mitigating effect are not yet clear, increased antioxidant defenses, have been held primarily responsible (antioxidant hypothesis). A systematic literature analysis, including “all” papers [Web of Science (WoS)-cited], addressing elevated CO2 effects on abiotic stress responses and antioxidants (105 papers), confirms the frequent occurrence of the stress mitigation effect. However, it also demonstrates that, in stress conditions, elevated CO2 is reported to increase antioxidants, only in about 22% of the observations (e.g., for polyphenols, peroxidases, superoxide dismutase, monodehydroascorbate reductase). In most observations, under stress and elevated CO2 the levels of key antioxidants and antioxidant enzymes are reported to remain unchanged (50%, e.g., ascorbate peroxidase, catalase, ascorbate), or even decreased (28%, e.g., glutathione peroxidase). Moreover, increases in antioxidants are not specific for a species group, growth facility, or stress type. It seems therefore unlikely that increased antioxidant defense is the major mechanism underlying CO2-mediated stress impact mitigation. Alternative processes, probably decreasing the oxidative challenge by reducing ROS production (e.g., photorespiration), are therefore likely to play important roles in elevated CO2 (relaxation hypothesis). Such parameters are however rarely investigated in connection with abiotic stress relief. Understanding the effect of elevated CO2 on plant growth and stress responses is imperative to understand the impact of climate changes on plant productivity. PMID:27200030

  12. Rationale for Antioxidant Supplementation in Sarcopenia

    PubMed Central

    Cerullo, Francesco; Gambassi, Giovanni; Cesari, Matteo

    2012-01-01

    Sarcopenia is an age-related clinical condition characterized by the progressive loss of motor units and wasting of muscle fibers resulting in decreased muscle function. The molecular mechanisms leading to sarcopenia are not completely identified, but the increased oxidative damage occurring in muscle cells during the course of aging represents one of the most accepted underlying pathways. In fact, skeletal muscle is a highly oxygenated tissue and the generation of reactive oxygen species is particularly enhanced in both contracting and at rest conditions. It has been suggested that oral antioxidant supplementation may contribute at reducing indices of oxidative stress both in animal and human models by reinforcing the natural endogenous defenses. Aim of the present paper is to discuss present evidence related to possible benefits of oral antioxidants in the prevention and treatment of sarcopenia. PMID:22292119

  13. Cupric ion reducing antioxidant capacity assay for antioxidants in human serum and for hydroxyl radical scavengers.

    PubMed

    Apak, Reşat; Güçlü, Kubilay; Ozyürek, Mustafa; Bektaşoğlu, Burcu; Bener, Mustafa

    2010-01-01

    Tests measuring the combined antioxidant effect of the nonenzymatic defenses in biological fluids may be useful in providing an index of the organism's capability to counteract reactive species known as pro-oxidants, resist oxidative damage, and combat oxidative stress-related diseases. The selected chromogenic redox reagent for the assay of human serum should be easily accessible, stable, selective, and respond to all types of biologically important antioxidants such as ascorbic acid, alpha-tocopherol, beta-carotene, reduced glutathione (GSH), uric acid, and bilirubin, regardless of chemical type or hydrophilicity. Our recently developed cupric reducing antioxidant capacity (CUPRAC) spectrophotometric method for a number of polyphenols and flavonoids using the copper(II)-neocuproine reagent in ammonium acetate buffer is now applied to a complete series of plasma antioxidants for the assay of total antioxidant capacity of serum, and the resulting absorbance at 450 nm is recorded either directly (e.g., for ascorbic acid, alpha-tocopherol, and glutathione) or after incubation at 50 degrees C for 20 min (e.g., for uric acid, bilirubin, and albumin), quantitation being made by means of a calibration curve. The lipophilic antioxidants, alpha-tocopherol and beta-carotene, are assayed in dichloromethane. Lipophilic antioxidants of serum are extracted with n-hexane from an ethanolic solution of serum subjected to centrifugation. Hydrophilic antioxidants of serum are assayed in the centrifugate after perchloric acid precipitation of proteins. The CUPRAC molar absorptivities, linear ranges, and TEAC (trolox equivalent antioxidant capacity) coefficients of the serum antioxidants are established, and the results are evaluated in comparison with the findings of the ABTS/TEAC reference method. The intra- and inter-assay coefficients of variation (CVs) are 0.7 and 1.5%, respectively, for serum. The CUPRAC assay proved to be efficient for glutathione and thiol-type antioxidants

  14. Nonenzymatic antioxidants in saliva of patients with systemic lupus erythematosus.

    PubMed

    Moori, M; Ghafoori, H; Sariri, R

    2016-03-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by autoantibody-directed self-antigens, immune complex formation and immune deregulation, resulting in damage to essentially all the organs. SLE is associated with the increased production of free radicals. Increase in free radicals or impaired antioxidant defense system in SLE causes oxidative stress. Considering that saliva could be a reflection of the state of health, the purpose of this study was to evaluate some antioxidants in the saliva and serum of patients with SLE and compare these with healthy individuals. This could help us in obtaining a possible marker in saliva in the future. During the course of the practical part of the project, 30 patients with SLE and 30 healthy controls were investigated. After centrifugation of un-stimulated saliva and blood samples, they were examined using spectrophotometric methods and the results were analyzed by statistical software. According to the results, concentrations of malondialdehyde, uric acid and total antioxidants were significantly increased but the level of reduced glutathion was reduced significantly in the saliva and serum of SLE patients as compared to controls. It is therefore suggested that antioxidant power is impaired in saliva and serum of SLE patients. As there was a positive correlation between the antioxidant level of saliva and blood serum, the antioxidant status of saliva could be an indicator of serum antioxidants.

  15. Lentinus squarrosulus (Mont.) mycelium enhanced antioxidant status in rat model

    PubMed Central

    Mhd Omar, Nor Adila; Abdullah, Sumaiyah; Abdullah, Noorlidah; Kuppusamy, Umah Rani; Abdulla, Mahmood Ameen; Sabaratnam, Vikineswary

    2015-01-01

    Aim Lentinus squarrosulus is an edible wild mushroom commonly found in Asia. This species has several interesting features such as rapid mycelial growth, and hence has the potential to be used as food, functional food, and nutraceuticals. Our previous study shows that L. squarrosulus contains potent antioxidant compounds in vitro. This study aims to investigate the in vivo bioavailability of L. squarrosulus mycelium extract and its antioxidant effect on biomarkers of antioxidant defense and oxidative stress. Methods Water extract of mycelial biomass of L. squarrosulus was analyzed for in vivo antioxidant effects, including cupric-reducing antioxidant capacity (CUPRAC), glutathione peroxidase (GPx), xanthine oxidase (XO), advanced oxidation protein products (AOPPs), and lipid hydroperoxides (LHPs) at 0 and 28 days. GPx and XO were also analyzed in liver homogenates. Normal Sprague Dawley rats were treated with 250 and 500 mg/kg of extract for 28 days. Results The serum CUPRAC level increased after treatment with both concentrations, indicating that there was sufficient bioavailability of the extract which contributed to the total antioxidant capacity. GPx activity in both serum and liver was increased and this correlated with LHP level after treatment with 250 mg/kg of extract, but XO activity was significantly decreased after treatment with 500 mg/kg of the extract. Lack of difference between AOPP levels implied that there were no significant changes in oxidative damage of protein after treatment. Conclusion This study clearly showed that L. squarrosulus mycelium antioxidant extract contains absorbable antioxidants that enter the circulating plasma and cause a significant acute increase in plasma antioxidant capacity. Thus, the water extract of L. squarrosulus mycelium, which can be obtained abundantly by liquid fermentation, may serve as an antioxidant ingredient in functional foods and nutraceuticals. PMID:26604694

  16. Defense against ballistic missiles

    SciTech Connect

    Mark, H. )

    1992-01-01

    A development history and development status evaluation is presented for weapons technologies capable of serving as defenses against nuclear-tipped ballistic missiles. The decisive turning-point in this history was the March 23, 1983 announcement by President Reagan of the Strategic Defense Initiative (SDI). Due to President Reagan's emphasis on population protection, 'global' defense systems have tended to dominate SDI design efforts. The most important SDI technical achievements to date encompass (1) miniature homig devices, (2) the upgrade of the Patriot SAM for missile-interception capabilities, (3) light exoatmospheric projectiles, such as 'Brilliant Pebbles', (4) successful laser-communications experiments, and (5) the warhead/decoy-discriminating Firepond lidar system. 7 refs.

  17. Defense Acquisition Structures and Capabilities Review

    DTIC Science & Technology

    2007-06-01

    requirements, budget, industry, and organizations. See Defense Acquisition Transformation Report to Congress, John Warner National Defense Authorization Act...Shortage of Skills and Talent. 3 Defense Acquisition Transformation Report to Congress, John Warner National Defense Authorization Act, Fiscal Year...Capabilities, Final Report, January 2004. 28 Secretary of Defense, Defense Acquisition Transformation Report to Congress, John War- ner National Defense

  18. Evaluation of the Antioxidant Activity of the Marine Pyrroloiminoquinone Makaluvamines

    PubMed Central

    Alonso, Eva; Alvariño, Rebeca; Leirós, Marta; Tabudravu, Jioji N.; Feussner, Klaus; Dam, Miriam A.; Rateb, Mostafa E.; Jaspars, Marcel; Botana, Luis M.

    2016-01-01

    Makaluvamines are pyrroloiminoquinones isolated from Zyzzya sponges. Until now, they have been described as topoisomerase II inhibitors with cytotoxic effects in diverse tumor cell lines. In the present work, seven makaluvamines were tested in several antioxidant assays in primary cortical neurons and neuroblastoma cells. Among the alkaloids studied, makaluvamine J was the most active in all the assays. This compound was able to reduce the mitochondrial damage elicited by the well-known stressor H2O2. The antioxidant properties of makaluvamine J are related to an improvement of the endogenous antioxidant defenses of glutathione and catalase. SHSY5Y assays proved that this compound acts as a Nrf2 activator leading to an improvement of antioxidant defenses. A low concentration of 10 nM is able to reduce the reactive oxygen species release and maintain a correct mitochondrial function. Based on these results, non-substituted nitrogen in the pyrrole plus the presence of a p-hydroxystyryl without a double bond seems to be the most active structure with a complete antioxidant effect in neuronal cells. PMID:27801775

  19. The Architecture of Thiol Antioxidant Systems among Invertebrate Parasites.

    PubMed

    Guevara-Flores, Alberto; Martínez-González, José de Jesús; Rendón, Juan Luis; Del Arenal, Irene Patricia

    2017-02-10

    The use of oxygen as the final electron acceptor in aerobic organisms results in an improvement in the energy metabolism. However, as a byproduct of the aerobic metabolism, reactive oxygen species are produced, leaving to the potential risk of an oxidative stress. To contend with such harmful compounds, living organisms have evolved antioxidant strategies. In this sense, the thiol-dependent antioxidant defense systems play a central role. In all cases, cysteine constitutes the major building block on which such systems are constructed, being present in redox substrates such as glutathione, thioredoxin, and trypanothione, as well as at the catalytic site of a variety of reductases and peroxidases. In some cases, the related selenocysteine was incorporated at selected proteins. In invertebrate parasites, antioxidant systems have evolved in a diversity of both substrates and enzymes, representing a potential area in the design of anti-parasite strategies. The present review focus on the organization of the thiol-based antioxidant systems in invertebrate parasites. Differences between these taxa and its final mammal host is stressed. An understanding of the antioxidant defense mechanisms in this kind of parasites, as well as their interactions with the specific host is crucial in the design of drugs targeting these organisms.

  20. Significance of antioxidant potential of plants and its relevance to therapeutic applications.

    PubMed

    Kasote, Deepak M; Katyare, Surendra S; Hegde, Mahabaleshwar V; Bae, Hanhong

    2015-01-01

    Oxidative stress has been identified as the root cause of the development and progression of several diseases. Supplementation of exogenous antioxidants or boosting endogenous antioxidant defenses of the body is a promising way of combating the undesirable effects of reactive oxygen species (ROS) induced oxidative damage. Plants have an innate ability to biosynthesize a wide range of non-enzymatic antioxidants capable of attenuating ROS- induced oxidative damage. Several in vitro methods have been used to screen plants for their antioxidant potential, and in most of these assays they revealed potent antioxidant activity. However, prior to confirming their in vivo therapeutic efficacy, plant antioxidants have to pass through several physiopharmacological processes. Consequently, the findings of in vitro and in vivo antioxidant potential assessment studies are not always the same. Nevertheless, the results of in vitro assays have been irrelevantly extrapolated to the therapeutic application of plant antioxidants without undertaking sufficient in vivo studies. Therefore, we have briefly reviewed the physiology and redox biology of both plants and humans to improve our understanding of plant antioxidants as therapeutic entities. The applications and limitations of antioxidant activity measurement assays were also highlighted to identify the precise path to be followed for future research in the area of plant antioxidants.

  1. 9. BASRELIEF DECORATION, 'DEFENSE', MURAL COMMEMORATING THE DEFENSE OF FORT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. BAS-RELIEF DECORATION, 'DEFENSE', MURAL COMMEMORATING THE DEFENSE OF FORT DEARBORN - Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River at North Michigan Avenue, Chicago, Cook County, IL

  2. Total antioxidant capacity in the black mussel ( Mytilus galloprovincialis) from Black Sea coasts

    NASA Astrophysics Data System (ADS)

    Moncheva, S.; Trakhtenberg, S.; Katrich, E.; Zemser, M.; Goshev, I.; Toledo, F.; Arancibia-Avila, P.; Doncheva, V.; Gorinstein, S.

    2004-03-01

    The aim of this investigation was to evaluate the total antioxidant radical scavenging capacity (TARSC) in tissue extracts for understanding biochemical adaptations involving the antioxidant defense system of a bivalve mussel, Mytilus galloprovincialis, sampled in polluted (Pol) and non-polluted (Npol) sites from Black Sea coasts. Antioxidant-rich polyphenol fractions were extracted from whole dry mussel tissue with methanol and water in different proportions. The extracts were screened for polyphenol content and their potential as antioxidants using various in vitro models, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH rad ), β-carotene-linoleate (β-carotene) and nitric oxide (NO rad ). The total polyphenol extract of the whole mussel tissue from polluted site (TPMEPol) showed the highest antioxidant capacity among all of the extracts with the tested methods and was comparable with the antioxidant capacity of butylated hydroxyanisole (BHA). The antioxidant capacities of this extract determined by DPPH rad , β-carotene and NO rad methods and polyphenol content showed the highest correlation coefficients ( R2) such as 0.9985, 0.9915 and 0.9895, respectively. The free polyphenol extracts (FPMEPol and FPMENPol) had lower antioxidant capacity than the two others of total polyphenols (TPMEPol and TPMENPol) with three scavenging methods. Responses were linear in all tested methods and the antioxidant capacity values of soluble antioxidants showed the following relative order: Trolox>BHA>TPMEPol>TPMENPol>FPMEPol>FPMENPol. Nutritional antioxidants, such as polyphenols, were probably the main antioxidant contribution to mussel antioxidants. The mussel extracts from the polluted site exhibited higher antioxidant capacity than from the non-polluted one. The results presented in this report indicate that the antioxidant capacity of the whole tissue of the mussel extract could possibly be a useful biomarker for aquatic environments.

  3. Exercise and oxidative stress: potential effects of antioxidant dietary strategies in sports.

    PubMed

    Pingitore, Alessandro; Lima, Giuseppina Pace Pereira; Mastorci, Francesca; Quinones, Alfredo; Iervasi, Giorgio; Vassalle, Cristina

    2015-01-01

    Free radicals are produced during aerobic cellular metabolism and have key roles as regulatory mediators in signaling processes. Oxidative stress reflects an imbalance between production of reactive oxygen species and an adequate antioxidant defense. This adverse condition may lead to cellular and tissue damage of components, and is involved in different physiopathological states, including aging, exercise, inflammatory, cardiovascular and neurodegenerative diseases, and cancer. In particular, the relationship between exercise and oxidative stress is extremely complex, depending on the mode, intensity, and duration of exercise. Regular moderate training appears beneficial for oxidative stress and health. Conversely, acute exercise leads to increased oxidative stress, although this same stimulus is necessary to allow an up-regulation in endogenous antioxidant defenses (hormesis). Supporting endogenous defenses with additional oral antioxidant supplementation may represent a suitable noninvasive tool for preventing or reducing oxidative stress during training. However, excess of exogenous antioxidants may have detrimental effects on health and performance. Whole foods, rather than capsules, contain antioxidants in natural ratios and proportions, which may act in synergy to optimize the antioxidant effect. Thus, an adequate intake of vitamins and minerals through a varied and balanced diet remains the best approach to maintain an optimal antioxidant status. Antioxidant supplementation may be warranted in particular conditions, when athletes are exposed to high oxidative stress or fail to meet dietary antioxidant requirements. Aim of this review is to discuss the evidence on the relationship between exercise and oxidative stress, and the potential effects of dietary strategies in athletes. The differences between diet and exogenous supplementation as well as available tools to estimate effectiveness of antioxidant intake are also reported. Finally, we advocate the need

  4. Defense Language Institute.

    ERIC Educational Resources Information Center

    Defense Language Inst., Washington, DC.

    Discussed in this Defense Language Institute (DLI) brochure are its intensive language programs' history, and its four schools, which are located in Monterey, California, Washington, D.C., Lackland Air Force Base, and Fort Bliss, Texas. Proficiency levels determined by the DLI and utilization of the audiolingual method are also described.…

  5. Defense Business Transformation

    DTIC Science & Technology

    2009-12-01

    other. SCM and ERP systems both contribute to the overall distribution and coordination of resources. Just as an ERP enhances information flow...inventory management system (Thureen 2008). It combines the Army’s disparate wholesale and retail inventories, into one combined system (Sparacino 2002...Studies.............................................................................. 73 1. Defense Integrated Military Human Resource System

  6. Strategic Defense Initiative program

    SciTech Connect

    Conachan, F.C.

    1991-05-01

    This paper discusses the Strategic Defense Initiative (SDI) program. It summarizes the major programmatic and technological lessons learned from the SDI program over the past 7 years. It provides information on: past uses of SDI funds, persistent optimism in planning and starting projects, evolution of SDI architecture, and accuracy of cost estimates.

  7. Radiological Defense Manual.

    ERIC Educational Resources Information Center

    Defense Civil Preparedness Agency (DOD), Washington, DC.

    Originally prepared for use as a student textbook in Radiological Defense (RADEF) courses, this manual provides the basic technical information necessary for an understanding of RADEF. It also briefly discusses the need for RADEF planning and expected postattack emergency operations. There are 14 chapters covering these major topics: introduction…

  8. Evolution of dietary antioxidants.

    PubMed

    Benzie, Iris F F

    2003-09-01

    Oxygen is vital for most organisms but, paradoxically, damages key biological sites. Oxygenic threat is met by antioxidants that evolved in parallel with our oxygenic atmosphere. Plants employ antioxidants to defend their structures against reactive oxygen species (ROS; oxidants) produced during photosynthesis. The human body is exposed to these same oxidants, and we have also evolved an effective antioxidant system. However, this is not infallible. ROS breach defences, oxidative damage ensues, accumulates with age, and causes a variety of pathological changes. Plant-based, antioxidant-rich foods traditionally formed the major part of the human diet, and plant-based dietary antioxidants are hypothesized to have an important role in maintaining human health. This hypothesis is logical in evolutionary terms, especially when we consider the relatively hypoxic environment in which humans may have evolved. In this paper, the human diet is discussed briefly in terms of its evolutionary development, different strategies of antioxidant defence are outlined, and evolution of dietary antioxidants is discussed from the perspectives of plant need and our current dietary requirements. Finally, possibilities in regard to dietary antioxidants, evolution, and human health are presented, and an evolutionary cost-benefit analysis is presented in relation to why we lost the ability to make ascorbic acid (vitamin C) although we retained an absolute requirement for it.

  9. [Carotenoids as natural antioxidants].

    PubMed

    Igielska-Kalwat, Joanna; Gościańska, Joanna; Nowak, Izabela

    2015-04-07

    Human organisms have many defence mechanisms able to neutralise the harmful effects of the reactive species of oxygen. Antioxidants play an important role in reducing the oxidative damage to the human organism. Carotenoids are among the strongest antioxidants. They have 11 coupled double bonds, so they can be classified as polyisoprenoids, show low polarity and can occur in acyclic, monocyclic or bicyclic forms. The carotenoids of the strongest antioxidant properties are lycopene, lutein, astaxanthin and β-carotene. Carotenoids with strong antioxidant properties have found wide application in medical, pharmaceutical and cosmetic industries. These compounds are highly active against both reactive oxygen species and free radicals. Comparing β-carotene, astaxanthin and lycopene with other antioxidants (e.g. vitamin C and E), it can be concluded that these compounds have higher antioxidant activity, e.g. against singlet oxygen. Astaxanthin is a stronger antioxidant compared to β-carotene, vitamin E and vitamin C, respectively 54, 14 and 65 times. Carotenoids have a salutary effect on our body, making it more resistant and strong to fight chronic diseases. The purpose of this article is to review the literature concerning free radicals and their adverse effects on the human body and carotenoids, as strong, natural antioxidants.

  10. Cyclodextrins and antioxidants.

    PubMed

    López-Nicolás, José Manuel; Rodríguez-Bonilla, Pilar; García-Carmona, Francisco

    2014-01-01

    In recent years, the growth of the functional foods industry has increased research into new compounds with high added value for use in the fortification of traditional products. One of the most promising functional food groups is those enriched in antioxidant compounds of a lipophilic nature. In spite of the numerous advantages reported for such antioxidant molecules, they may also have disadvantages that impede their use in functional foods, although these problems may well avoided by the use of encapsulant agents such as cyclodextrins. This explains the recent increase in the number of research papers dealing with the complexation of different guest molecules possesing important antioxidant properties using natural and modified cyclodextrins. This paper presents a review of the most recent studies on the complexes formed between several important types of antioxidant compounds and cyclodextrins, focusing on the contradictory data reported in the literature concerning to the antioxidant activity of the host/guest molecule complexes, the different complexation constants reported for identical complexes, the bioavailability of the antioxidant compound in the presence of cyclodextrins and recommendation concerning the use of natural or modified cyclodextrins. Moreover, the use of cyclodextrins as antibrowning agents to prevent enzymatic browning in different foods is revised. Finally, we look at studies which suggest that cyclodextrins act as ''secondary antioxidants," enhancing the ability of traditional antioxidants to prevent enzymatic browning.

  11. Tolerance and antioxidant response of a dark septate endophyte (DSE), Exophiala pisciphila, to cadmium stress.

    PubMed

    Zhan, Fangdong; He, Yongmei; Li, Tao; Yang, Yun-ya; Toor, Gurpal S; Zhao, Zhiwei

    2015-01-01

    The growth, oxidative damage and antioxidant response of Exophiala pisciphila ACCC32496, a dark septate endophyte isolated from an abandoned lead-zinc mining area, were measured at cadmium (Cd) concentrations of 0, 25, 50, 100, 200 and 400 mg L(-1). The EC50 values of E. pisciphila ACCC32496 to Cd were 332.2 mg L(-1) after 30 days on solid medium and 111.2 mg L(-1) after 7 days in liquid medium. Cd stress markedly stimulated the production of superoxide anion, H2O2 and malondialdehyde in the fungal mycelia. The activities of superoxide dismutase and catalase reached their maxima at 100 mg L(-1) Cd. The glutathione and non-protein thiol contents, along with the total antioxidant capability, reached their maxima at 50 mg L(-1) Cd. Low Cd concentrations induced a noticeable increase in antioxidant defense, while high Cd concentrations decreased the antioxidant defense.

  12. Defense Spending and the Economy

    DTIC Science & Technology

    1983-12-07

    DEFENSE SPENDING AND THE ECONOMY Rudolph G. Penner Director Congressional Budget Office Before the Task Force on Economic Policy and Growth...TITLE AND SUBTITLE Defense Spending and the Economy 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER...Administration budgets have proposed even more defense spending and less nondefense spending than provided in the resolution. Additional emphasis on defense

  13. Phenolic composition and antioxidant properties of poplar bud (Populus nigra) extract: individual antioxidant contribution of phenolics and transcriptional effect on skin aging.

    PubMed

    Dudonné, Stéphanie; Poupard, Pascal; Coutière, Philippe; Woillez, Marion; Richard, Tristan; Mérillon, Jean-Michel; Vitrac, Xavier

    2011-05-11

    The Populus species possess great potential for therapeutical applications, especially for their known anti-inflammatory properties. The antioxidant properties of propolis, a hive product collected by honey bees mainly from poplar bud exudates, suggest that poplar buds also possess antioxidant properties. Here is reported the characterization of the antioxidant properties of an aqueous poplar bud (Populus nigra) extract. It presented a high total phenolic content, and moderate antioxidant properties as determined by ORAC assay. The main phenolic compounds identified were phenolic acids and flavonoid aglycons. These phenolic compounds were analyzed by ORAC assay for their individual antioxidant activity, in order to determine the major contributors to the total antioxidant activity of the extract. Thanks to their high antioxidant activity, caffeic and p-coumaric acids were identified as the major antioxidant components. Representing only 3.5% of its dry weight, these compounds represented together about 50% of the total antioxidant activity of the extract. The antioxidant properties of poplar bud extract and the phenolic compounds identified were also analyzed by cellular antioxidant activity assay (CAA), which was weakly correlated with ORAC assay. The transcriptional effect of poplar bud extract on skin aging was evaluated in vitro on a replicative senescence model of normal human dermal fibroblasts, using a customized DNA macroarray specifically designed to investigate skin aging markers. Among the detected genes, poplar bud extract significantly regulated genes involved in antioxidant defenses, inflammatory response and cell renewal. The collective antioxidant properties and transcriptional effect of this extract suggest potential antiaging properties which could be utilized in cosmetic and nutraceutical formulations.

  14. Defense on the Move: Ant-Based Cyber Defense

    SciTech Connect

    Fink, Glenn A.; Haack, Jereme N.; McKinnon, Archibald D.; Fulp, Errin W.

    2014-04-15

    Many common cyber defenses (like firewalls and IDS) are as static as trench warfare allowing the attacker freedom to probe them at will. The concept of Moving Target Defense (MTD) adds dynamism to the defender side, but puts the systems to be defended themselves in motion, potentially at great cost to the defender. An alternative approach is a mobile resilient defense that removes attackers’ ability to rely on prior experience without requiring motion in the protected infrastructure itself. The defensive technology absorbs most of the cost of motion, is resilient to attack, and is unpredictable to attackers. The Ant-Based Cyber Defense (ABCD) is a mobile resilient defense providing a set of roaming, bio-inspired, digital-ant agents working with stationary agents in a hierarchy headed by a human supervisor. The ABCD approach provides a resilient, extensible, and flexible defense that can scale to large, multi-enterprise infrastructures like the smart electric grid.

  15. The evaluation of non-enzymatic antioxidants effects in limiting tumor- associated oxidative stress, in a tumor rat model

    PubMed Central

    Grigorescu, R; Gruia, MI; Nacea, V; Nitu, C; Negoita, V; Glavan, D

    2015-01-01

    Active oxygen species are produced as a consequence of normal aerobic metabolism. Of these, free radicals are usually metabolized or inactivated in vivo by a team of antioxidants. Individual members are a trained team fighting antioxidants to prevent the generation of ROS, destroy or oxidizing potential of capture. In terms of physiological oxidative stress, induced tissue attack is minimal. A relative or absolute deficiency in the antioxidant defense may lead to increased oxidative stress and this event is associated with both the causes and consequences of diseases and cancer, included here. The aim of the study is to identify the role of antioxidant defense systems and the reduction of oxidative stress in dynamic growth and development of malignant tumors. Our in vivo study was developed and referred to carcinosarcoma carriers Wistar rats treated with non-enzymatic antioxidants: vitamin C, vitamin A, zinc salt (II), and arginine in various combinations. Treatment was initiated three weeks before tumor induction. PMID:26664481

  16. The evaluation of non-enzymatic antioxidants effects in limiting tumor- associated oxidative stress, in a tumor rat model.

    PubMed

    Grigorescu, R; Gruia, M I; Nacea, V; Nitu, C; Negoita, V; Glavan, D

    2015-01-01

    Active oxygen species are produced as a consequence of normal aerobic metabolism. Of these, free radicals are usually metabolized or inactivated in vivo by a team of antioxidants. Individual members are a trained team fighting antioxidants to prevent the generation of ROS, destroy or oxidizing potential of capture. In terms of physiological oxidative stress, induced tissue attack is minimal. A relative or absolute deficiency in the antioxidant defense may lead to increased oxidative stress and this event is associated with both the causes and consequences of diseases and cancer, included here. The aim of the study is to identify the role of antioxidant defense systems and the reduction of oxidative stress in dynamic growth and development of malignant tumors. Our in vivo study was developed and referred to carcinosarcoma carriers Wistar rats treated with non-enzymatic antioxidants: vitamin C, vitamin A, zinc salt (II), and arginine in various combinations. Treatment was initiated three weeks before tumor induction.

  17. Antioxidants in Translational Medicine

    PubMed Central

    Schmidt, Harald H.H.W.; Stocker, Roland; Vollbracht, Claudia; Paulsen, Gøran; Riley, Dennis

    2015-01-01

    Abstract Significance: It is generally accepted that reactive oxygen species (ROS) scavenging molecules or antioxidants exert health-promoting effects and thus their consumption as food additives and nutraceuticals has been greatly encouraged. Antioxidants may be beneficial in situations of subclinical deficiency and increased demand or acutely upon high-dose infusion. However, to date, there is little clinical evidence for the long-term benefit of most antioxidants. Alarmingly, recent evidence points even to health risks, in particular for supplements of lipophilic antioxidants. Recent Advances: The biological impact of ROS depends not only on their quantities but also on their chemical nature, (sub)cellular and tissue location, and the rates of their formation and degradation. Moreover, ROS serve important physiological functions; thus, inappropriate removal of ROS may cause paradoxical reductive stress and thereby induce or promote disease. Critical Issues: Any recommendation on antioxidants must be based on solid clinical evidence and patient-relevant outcomes rather than surrogate parameters. Future Directions: Such evidence-based use may include site-directed application, time-limited high dosing, (functional) pharmacological repair of oxidized biomolecules, and triggers of endogenous antioxidant response systems. Ideally, these approaches need guidance by patient stratification through predictive biomarkers and possibly imaging modalities. Antioxid. Redox Signal. 23, 1130–1143. PMID:26154592

  18. Antioxidant therapies in COPD

    PubMed Central

    Rahman, Irfan

    2006-01-01

    Oxidative stress is an important feature in the pathogenesis of COPD. Targeting oxidative stress with antioxidants or boosting the endogenous levels of antioxidants is likely to be beneficial in the treatment of COPD. Antioxidant agents such as thiol molecules (glutathione and mucolytic drugs, such as N-acetyl-L-cysteine and N-acystelyn), dietary polyphenols (curcumin, resveratrol, green tea, catechins/quercetin), erdosteine, and carbocysteine lysine salt, all have been reported to control nuclear factor-kappaB (NF-κ B) activation, regulation of glutathione biosynthesis genes, chromatin remodeling, and hence inflammatory gene expression. Specific spin traps such as α-phenyl-N-tert-butyl nitrone, a catalytic antioxidant (ECSOD mimetic), porphyrins (AEOL 10150 and AEOL 10113), and a superoxide dismutase mimetic M40419 have also been reported to inhibit cigarette smoke-induced inflammatory responses in vivo. Since a variety of oxidants, free radicals, and aldehydes are implicated in the pathogenesis of COPD, it is possible that therapeutic administration of multiple antioxidants will be effective in the treatment of COPD. Various approaches to enhance lung antioxidant capacity and clinical trials of antioxidant compounds in COPD are discussed. PMID:18046899

  19. Biology of Ageing and Role of Dietary Antioxidants

    PubMed Central

    Peng, Cheng; Wang, Xiaobo; Chen, Jingnan; Jiao, Rui; Li, Yuk Man; Zuo, Yuanyuan; Lei, Lin; Ma, Ka Ying; Huang, Yu

    2014-01-01

    Interest in relationship between diet and ageing is growing. Research has shown that dietary calorie restriction and some antioxidants extend lifespan in various ageing models. On the one hand, oxygen is essential to aerobic organisms because it is a final electron acceptor in mitochondria. On the other hand, oxygen is harmful because it can continuously generate reactive oxygen species (ROS), which are believed to be the factors causing ageing of an organism. To remove these ROS in cells, aerobic organisms possess an antioxidant defense system which consists of a series of enzymes, namely, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR). In addition, dietary antioxidants including ascorbic acid, vitamin A, vitamin C, α-tocopherol, and plant flavonoids are also able to scavenge ROS in cells and therefore theoretically can extend the lifespan of organisms. In this connection, various antioxidants including tea catechins, theaflavins, apple polyphenols, black rice anthocyanins, and blueberry polyphenols have been shown to be capable of extending the lifespan of fruit flies. The purpose of this review is to brief the literature on modern biological theories of ageing and role of dietary antioxidants in ageing as well as underlying mechanisms by which antioxidants can prolong the lifespan with focus on fruit flies as an model. PMID:24804252

  20. Biology of ageing and role of dietary antioxidants.

    PubMed

    Peng, Cheng; Wang, Xiaobo; Chen, Jingnan; Jiao, Rui; Wang, Lijun; Li, Yuk Man; Zuo, Yuanyuan; Liu, Yuwei; Lei, Lin; Ma, Ka Ying; Huang, Yu; Chen, Zhen-Yu

    2014-01-01

    Interest in relationship between diet and ageing is growing. Research has shown that dietary calorie restriction and some antioxidants extend lifespan in various ageing models. On the one hand, oxygen is essential to aerobic organisms because it is a final electron acceptor in mitochondria. On the other hand, oxygen is harmful because it can continuously generate reactive oxygen species (ROS), which are believed to be the factors causing ageing of an organism. To remove these ROS in cells, aerobic organisms possess an antioxidant defense system which consists of a series of enzymes, namely, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR). In addition, dietary antioxidants including ascorbic acid, vitamin A, vitamin C, α-tocopherol, and plant flavonoids are also able to scavenge ROS in cells and therefore theoretically can extend the lifespan of organisms. In this connection, various antioxidants including tea catechins, theaflavins, apple polyphenols, black rice anthocyanins, and blueberry polyphenols have been shown to be capable of extending the lifespan of fruit flies. The purpose of this review is to brief the literature on modern biological theories of ageing and role of dietary antioxidants in ageing as well as underlying mechanisms by which antioxidants can prolong the lifespan with focus on fruit flies as an model.

  1. Avian host defense peptides.

    PubMed

    Cuperus, Tryntsje; Coorens, Maarten; van Dijk, Albert; Haagsman, Henk P

    2013-11-01

    Host defense peptides (HDPs) are important effector molecules of the innate immune system of vertebrates. These antimicrobial peptides are also present in invertebrates, plants and fungi. HDPs display broad-spectrum antimicrobial activities and fulfill an important role in the first line of defense of many organisms. It is becoming increasingly clear that in the animal kingdom the functions of HDPs are not confined to direct antimicrobial actions. Research in mammals has indicated that HDPs have many immunomodulatory functions and are also involved in other physiological processes ranging from development to wound healing. During the past five years our knowledge about avian HDPs has increased considerably. This review addresses our current knowledge on the evolution, regulation and biological functions of HDPs of birds.

  2. Natural host defense mechanisms.

    PubMed

    Heggers, J P

    1979-10-01

    Severe injury, whether the result of a major accident, a large burn, or a complicated surgical operation, often results in sepsis. Under such conditions both specific and nonspecific host defense systems are affected. The individual facets of major concern are chemotaxis, phagocytosis, intracellular killing, complement depletion, and depression of humoral and cellular mediated immunity. The most profound changes occur in cell-mediated immunity. Within a few hours o injury, the number of circulating T cells becomes depleted, concomitantly thoracic duct lymphocytes are markedly reduced. This change is not only quantitative but functional. The clinical impact of these deficient host defense mechanisms lies in the fact that low virulent organisms may become a lethal threat to the injured patient. Currently, investigators are attempting to reverse thse deficiencies through the use of immunotherapy.

  3. Plant Defense against Insect Herbivores

    PubMed Central

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar. Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged tissues, which thereafter reinforce their defense by producing different, mostly low molecular weight, defense compounds. These bioactive specialized plant defense compounds may repel or intoxicate insects, while defense proteins often interfere with their digestion. Volatiles are released upon herbivory to repel herbivores, attract predators or for communication between leaves or plants, and to induce defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects have adapted to resist plant defenses, and in some cases even sequester the compounds and reuse them in their own defense. Both plant defense and insect adaptation involve metabolic costs, so most plant-insect interactions reach a stand-off, where both host and herbivore survive although their development is suboptimal. PMID:23681010

  4. Getting Defense Acquisition Right

    DTIC Science & Technology

    2017-01-01

    Buying Power 1.0 Figure 2. Better Buying Power 2.0 Figure 3. Better Buying Power 3.0 179 Figure 4. Contract Cost Growth on Highest Risk (Major...Crossing Critical Congressional Cost- Growth Thresholds iv Getting Defense Acquisition Right 67 96 97 184 Table 1. Root...Causes for Major Programs Crossing Critical Con­ gressional Cost- Growth Thresholds or Other Major Problems 185 Figure 8. Planned Length of Active

  5. AFRL Defensive IO Programs

    DTIC Science & Technology

    2007-11-02

    NUMBER Air Force Research Laboratory 525 Brooks Road, Rome NY 13441 11. SUPPLEMENTARY NOTES 12a. DISTRIBUTION / AVAILABILITY STATEMENT Approved for...entire NOSC crew Air Force Enterprise Defense Moving from Data-Centric to Mission-Centric Operations 16 Summary • The AFRL /IF program includes all...William E.; Simpson, Lt. Col Richard 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Air Force

  6. Foreign Internal Defense

    DTIC Science & Technology

    2010-07-12

    projects conducted were a primary factor in the decision to form the JTF. Other JTFs may be organized to accomplish specific functional missions such...IV-8 Table of Contents viii JP 3-22 VI-1 Force Employment Factors in Foreign Internal Defense Operations ........ VI-2 VI-2...US combat operations in support of FID Executive Summary xi operations, which requires a Presidential decision and serves only as a temporary

  7. Soviet strategic defense technology

    SciTech Connect

    Stubbs, E.

    1987-04-01

    The present status of the Soviet program suggests several observations that have a bearing on predicting the future of the Soviet strategic defense program and its implications for the US: 1. The Soviet Union appears to have a continuing interest in ABM defenses, although ASATs seem to be a much lower priority. 2. The Soviet technology fielded to date was well within the American grasp 10 years ago. Where advanced and as yet undeployed technologies are concerned, the difference seems to be smaller; perhaps as little as five or seven years, with approximate parity in particle-beam research. 3. The Soviet Union, possibly more sensitive to prestige considerations, appears to be much more inclined than the US to demonstrate and deploy a technology before it is actually fully operational, and to undertake field modifications later. They also are much more reluctant to retire aging and obsolete technologies. As a result, they presently possess the world's only deployed ASAT and ABM systems, however, doubtful their actual operational effectiveness might be. 4. Soviet strategic defenses tend to be more fragmentary in design, reflecting their difficulties with the supporting and integrative technologies such as sensing, signal processing, heavy-lift boosters, and computing hardware and software. 5. The Soviets should also be expected to explore alternative avenues of near-term response to SDI, for example by expanding their strategic nuclear arsenal. 28 references, 1 figure, 2 tables.

  8. Pro-oxidant and antioxidant processes in aquatic invertebrates.

    PubMed

    Canesi, Laura

    2015-03-01

    Most aquatic organisms behave as conformers with respect to environmental variables, including changes in O2 availability. Aquatic species that show tolerance to hypoxia/anoxia or hyperoxia can be excellent models for investigating physiological and biochemical adaptations that deal with changing O2 and consequent changes in metabolic rate and production of reactive oxygen species (ROS). Here, I summarize selected data on ROS production and antioxidant defenses in a model marine invertebrate, the bivalve Mytilus, under different environmental and physiological conditions. An example of other bivalves adapted to particular environments (the Antarctic Sea) is also reported. These studies contributed to the knowledge on pro-oxidant and antioxidant processes in aquatic invertebrates from comparative and environmental perspectives. A common role for metallothioneins in antioxidant protection in mammals and aquatic invertebrates is underlined in different conditions, from human disease to responses to environmental exposure to heavy metals.

  9. Antioxidant content of foods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant-based foods, especially fruits, vegetables, and nuts, contain bioactive components which have various biological functions, including free radical scavenging and metal chelating (antioxidant), inhibition of lipid peroxidation, anti-inflammatory properties, etc. Oxidative stress may contribute...

  10. Antioxidant Activity during Tumor Progression: A Necessity for the Survival of Cancer Cells?

    PubMed Central

    Hawk, Mark A.; McCallister, Chelsea; Schafer, Zachary T.

    2016-01-01

    Antioxidant defenses encompass a variety of distinct compounds and enzymes that are linked together through their capacity to neutralize and scavenge reactive oxygen species (ROS). While the relationship between ROS and tumorigenesis is clearly complex and context dependent, a number of recent studies have suggested that neutralizing ROS can facilitate tumor progression and metastasis in multiple cancer types through distinct mechanisms. These studies therefore infer that antioxidant activity may be necessary to support the viability and/or the invasive capacity of cancer cells during tumor progression and metastasis. Here, we discuss some of the accumulating evidence suggesting a role for antioxidant activity in facilitating tumor progression. PMID:27754368

  11. Antioxidant therapeutics for schizophrenia.

    PubMed

    Reddy, Ravinder; Reddy, Rajiv

    2011-10-01

    Pharmaceutical treatment for millions worldwide who have schizophrenia is limited to a handful of antipsychotics. Despite the proven efficacy of these drugs, the overall outcome for schizophrenia remains suboptimal. Thus, alternative treatment options are urgently needed. One possible approach may be antioxidant therapy. The extant evidence for the role of oxidative stress in the pathophysiology of schizophrenia offers a hypothesis-derived therapeutic approach in the form of antioxidants. Vitamins C and E, for example, are suitable for human clinical trials because they are readily available, inexpensive, and relatively safe. Research into the therapeutic use of antioxidants in schizophrenia can be grouped into two main clusters: for psychopathology and for side effects. Of these studies, some have been carefully conducted, but majority are open label. Use of antioxidants for treatment-related side effects has been more extensively investigated. The totality of the evidence to date suggests that specific antioxidants, such as N-acetyl cysteine, may offer tangible benefits for the clinical syndrome of schizophrenia, and vitamin E may offer salutary effects on glycemic effects of antipsychotics. However, a great deal of fundamental clinical research remains to be done before antioxidants can be routinely used therapeutically for schizophrenia and treatment-related complications.

  12. Synthetic plant defense elicitors

    PubMed Central

    Bektas, Yasemin; Eulgem, Thomas

    2015-01-01

    To defend themselves against invading pathogens plants utilize a complex regulatory network that coordinates extensive transcriptional and metabolic reprogramming. Although many of the key players of this immunity-associated network are known, the details of its topology and dynamics are still poorly understood. As an alternative to forward and reverse genetic studies, chemical genetics-related approaches based on bioactive small molecules have gained substantial popularity in the analysis of biological pathways and networks. Use of such molecular probes can allow researchers to access biological space that was previously inaccessible to genetic analyses due to gene redundancy or lethality of mutations. Synthetic elicitors are small drug-like molecules that induce plant defense responses, but are distinct from known natural elicitors of plant immunity. While the discovery of some synthetic elicitors had already been reported in the 1970s, recent breakthroughs in combinatorial chemical synthesis now allow for inexpensive high-throughput screens for bioactive plant defense-inducing compounds. Along with powerful reverse genetics tools and resources available for model plants and crop systems, comprehensive collections of new synthetic elicitors will likely allow plant scientists to study the intricacies of plant defense signaling pathways and networks in an unparalleled fashion. As synthetic elicitors can protect crops from diseases, without the need to be directly toxic for pathogenic organisms, they may also serve as promising alternatives to conventional biocidal pesticides, which often are harmful for the environment, farmers and consumers. Here we are discussing various types of synthetic elicitors that have been used for studies on the plant immune system, their modes-of-action as well as their application in crop protection. PMID:25674095

  13. Synthetic plant defense elicitors.

    PubMed

    Bektas, Yasemin; Eulgem, Thomas

    2014-01-01

    To defend themselves against invading pathogens plants utilize a complex regulatory network that coordinates extensive transcriptional and metabolic reprogramming. Although many of the key players of this immunity-associated network are known, the details of its topology and dynamics are still poorly understood. As an alternative to forward and reverse genetic studies, chemical genetics-related approaches based on bioactive small molecules have gained substantial popularity in the analysis of biological pathways and networks. Use of such molecular probes can allow researchers to access biological space that was previously inaccessible to genetic analyses due to gene redundancy or lethality of mutations. Synthetic elicitors are small drug-like molecules that induce plant defense responses, but are distinct from known natural elicitors of plant immunity. While the discovery of some synthetic elicitors had already been reported in the 1970s, recent breakthroughs in combinatorial chemical synthesis now allow for inexpensive high-throughput screens for bioactive plant defense-inducing compounds. Along with powerful reverse genetics tools and resources available for model plants and crop systems, comprehensive collections of new synthetic elicitors will likely allow plant scientists to study the intricacies of plant defense signaling pathways and networks in an unparalleled fashion. As synthetic elicitors can protect crops from diseases, without the need to be directly toxic for pathogenic organisms, they may also serve as promising alternatives to conventional biocidal pesticides, which often are harmful for the environment, farmers and consumers. Here we are discussing various types of synthetic elicitors that have been used for studies on the plant immune system, their modes-of-action as well as their application in crop protection.

  14. Allergic Host Defenses

    PubMed Central

    Palm, Noah W.; Rosenstein, Rachel K.

    2012-01-01

    Allergies are generally thought to be a detrimental outcome of a mistargeted immune response that evolved to provide immunity to macro-parasites. Here we present arguments to suggest that allergic immunity plays an important role in host defense against noxious environmental substances, including venoms, hematophagous fluids, environmental xenobiotics and irritants. We argue that appropriately targeted allergic reactions are beneficial, although they can become detrimental when excessive. Furthermore, we suggest that allergic hypersensitivity evolved to elicit anticipatory responses and to promote avoidance of suboptimal environments. PMID:22538607

  15. Does strategic defense breed offense

    SciTech Connect

    York, H.

    1987-01-01

    The author examines the question of whether strategic defense activity, in any form, stimulates a related offensive activity. The author studies four post-World II efforts of the superpowers to develop and deploy strategic defenses. The author then derives lessons from those cases that he applies to his analysis of President Reagan's Strategic Defense Initiative. Commentaries on the author's analysis are provided by four scholars.

  16. Hydroxyproline-rich glycopeptide signals in potato elicit signalling associated with defense against insects and pathogens.

    PubMed

    Bhattacharya, Ramcharan; Koramutla, Murali Krishna; Negi, Manisha; Pearce, Gregory; Ryan, Clarence A

    2013-06-01

    HypSys peptides are 18-20 amino acids glycopeptide defense signal first discovered in tobacco and tomato that activate expression of defensive genes against insect-herbivores. Discovery of their orthologs in other Solanaceaous and nonsolanaceous plants demonstrated their possible ubiquitous nature and species specific functional diversity. In our continued search to establish the paradigm of defense signalling by HypSys peptides, we isolated a cDNA from potato leaves encoding putative analogs of tomato HypSys peptides flanked by conserved proteolytic cleavage sites. The gene encoding the cDNA was a member of a gene family in the tetraploid genome of potato and its expression was transcriptionally activated by wounding and methyl jasmonate. The deduced precursor protein contained a leader peptidase splice site and three putative HypSys peptides with conserved N- and C-termini along with central proline-rich motifs. In defense signalling, the three HypSys peptides elicit H₂O₂ generation in vivo and activate several antioxidant defensive enzymes in young potato leaves. Similar to potato systemin, the HypSys peptides activate the expression of octadecanoid pathway genes and protease inhibitors for insect defense. In addition, the HypSys peptides also activate the essential genes of the innate pathogen defense response in young potato leaves, acting as common elicitors of signalling associated with anti-herbivore and anti-pathogen defense in potato.

  17. Control Processes and Defense Mechanisms

    PubMed Central

    HOROWITZ, MARDI; COOPER, STEVEN; FRIDHANDLER, BRAM; PERRY, J. CHRISTOPHER; BOND, MICHAEL; VAILLANT, GEORGE

    1992-01-01

    Defense-mechanism theory and control-process theory are related psychodynamic approaches to explaining and classifying how people ward off emotional upsets. Although both theories explain defensive maneuvers in the same motivational terms, each defines categories different1y. Classic categories define defense mechanisms at a relatively macroscopic level, whereas control-process theory aims at relatively microgenetic analysis of how cognitive maneuvers—involving what is thought, how it is thought, and how it is organized—may generate defensive states. The theories are not contradictory, but they are focused on different levels of observation; it is useful to compare how these classifications are applied to specific case material. PMID:22700114

  18. Skin and antioxidants.

    PubMed

    Poljsak, Borut; Dahmane, Raja; Godic, Aleksandar

    2013-04-01

    It is estimated that total sun exposure occurs non-intentionally in three quarters of our lifetimes. Our skin is exposed to majority of UV radiation during outdoor activities, e.g. walking, practicing sports, running, hiking, etc. and not when we are intentionally exposed to the sun on the beach. We rarely use sunscreens during those activities, or at least not as much and as regular as we should and are commonly prone to acute and chronic sun damage of the skin. The only protection of our skin is endogenous (synthesis of melanin and enzymatic antioxidants) and exogenous (antioxidants, which we consume from the food, like vitamins A, C, E, etc.). UV-induced photoaging of the skin becomes clinically evident with age, when endogenous antioxidative mechanisms and repair processes are not effective any more and actinic damage to the skin prevails. At this point it would be reasonable to ingest additional antioxidants and/or to apply them on the skin in topical preparations. We review endogenous and exogenous skin protection with antioxidants.

  19. The Relationship between Inflation and Defense Expenditures.

    DTIC Science & Technology

    1979-12-01

    All Federal Expenditures .. ......... . 22 2. Defense Expenditures .... ........... 24 3. Suggested Research on the Impact of DoD Spending ...only major study specifically simulating changes in military spending implied that defense and non- defense expenditures have identical impacts upon...analyzed in Chapter I is that defense expenditures are not assigned a central role in generating inflation. Even when defense spending is incorporated

  20. Do Oil Exports Fuel Defense Spending?

    DTIC Science & Technology

    2010-02-01

    defense spending , and there were years when defense expenditures actually increased. Additionally, in countries that did... spending , especially defense expenditures , but such is not always the case. One can study the impact of oil revenues on defense spending by using a...oil revenue levels and levels of military expenditures , however, appear weak, meaning that attempts to limit defense spending by tinkering with

  1. Antipredator defenses predict diversification rates

    PubMed Central

    Arbuckle, Kevin; Speed, Michael P.

    2015-01-01

    The “escape-and-radiate” hypothesis predicts that antipredator defenses facilitate adaptive radiations by enabling escape from constraints of predation, diversified habitat use, and subsequently speciation. Animals have evolved diverse strategies to reduce the direct costs of predation, including cryptic coloration and behavior, chemical defenses, mimicry, and advertisement of unprofitability (conspicuous warning coloration). Whereas the survival consequences of these alternative defenses for individuals are well-studied, little attention has been given to the macroevolutionary consequences of alternative forms of defense. Here we show, using amphibians as the first, to our knowledge, large-scale empirical test in animals, that there are important macroevolutionary consequences of alternative defenses. However, the escape-and-radiate hypothesis does not adequately describe them, due to its exclusive focus on speciation. We examined how rates of speciation and extinction vary across defensive traits throughout amphibians. Lineages that use chemical defenses show higher rates of speciation as predicted by escape-and-radiate but also show higher rates of extinction compared with those without chemical defense. The effect of chemical defense is a net reduction in diversification compared with lineages without chemical defense. In contrast, acquisition of conspicuous coloration (often used as warning signals or in mimicry) is associated with heightened speciation rates but unchanged extinction rates. We conclude that predictions based on the escape-and-radiate hypothesis must incorporate the effect of traits on both speciation and extinction, which is rarely considered in such studies. Our results also suggest that knowledge of defensive traits could have a bearing on the predictability of extinction, perhaps especially important in globally threatened taxa such as amphibians. PMID:26483488

  2. 78 FR 78163 - Eligibility of the Gulf Cooperation Council To Receive Defense Articles and Defense Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-24

    ... Cooperation Council To Receive Defense Articles and Defense Services Under the Foreign Assistance Act of 1961... that the furnishing of defense articles and defense services to the Gulf Cooperation Council...

  3. Dietary antioxidant activities in different germplasms of Mucuna.

    PubMed

    Uma, Sundaram; Gurumoorthi, Parameswaran

    2013-07-01

    Mucuna pruriens, an underutilized native legume of South India has been reported to have high levels of L-Dopa, and used in the treatment of Parkinson's disease. Cellular damage arising from reactive oxygen and nitrogen species is said to cause neurodegenerative disorders. Antioxidants could assuage this oxidative damage of tissue directly and/or indirectly by enhancing natural defenses and also scavenging the free radicals. In this context, the antioxidative potential of different germplasm of Mucuna species was analyzed. Assays were performed to evaluate the enzymatic and nonenzymatic antioxidants in the extracts. Methanolic extracts of Mucuna (black germplasm) yielded high levels dietary antioxidants viz., flavonoids, alkaloids, saponins, steroids and phlobotannins qualitatively. Tannins, total phenols, flavanoids, and steroids accounted for 13.60±1.8 tannic acid equivalents, 58.47±3.19 gallic acid equivalents, 23.7±3.12 quercetin equivalents, and 20.3±1.0 mg per 100 mg β-sitosterol equivalents, respectively. Percentage of scavenging activity against hydroxyl, superoxide anion, nitric oxide, and hydrogen peroxide radicals were 39.12%; 57.1%; 41.26%, and 25.68%, respectively. Reducing capacity (17.74%) was seen to concurrently increase with extract concentration. Catalase, glutathione reductase, and polyphenol oxidase activities were found to be 30.15; 26.6 and 42.5 μmol/mg of protein, respectively. The methanolic extract yielded the most potent levels of dietary antioxidants and exhibited high free-radical-scavenging activity.

  4. Antioxidant status in MgO nanoparticle-exposed rats.

    PubMed

    Kiranmai, G; Reddy, A Rama Narsimha

    2013-11-01

    In this present study, antioxidant status was evaluated in rat serum following exposure to magnesium oxide (MgO) nanoparticles. The lungs of rats were intratracheally instilled with (single dose) phosphate-buffered saline (PBS) + 1% of Tween 80 (solvent control) or MgO or carbonyl iron (negative control) or quartz particles (positive control) at a dose of 1 and 5 mg/kg of body weight. The blood samples were collected at 1, 7, and 30 days of postinstillation of nanoparticles after their exposure, and different parameters were estimated to assess the oxidative stress induced by the instillation of MgO. Exposure of rats to MgO produced a significant (p < 0.05) dose-dependent reduction in blood total antioxidant capacity, superoxide dismutase, and catalase activity levels than PBS + 1% Tween 80 control group. This reduction in the antioxidant capacity in MgO nanoparticle-exposed rats indicates the reduction in antioxidant defense mechanisms due to the instillation of MgO. These results indicate that exposure to MgO nanoparticles induces oxidative stress by reducing the total antioxidant capacity in rats. The findings suggest possible occupational health hazard in chronic exposures.

  5. The doctor's defense.

    PubMed

    Tur, Richard H S

    2002-10-01

    The paper takes as its point of departure a relatively recent case which attracted publicity in Britain, concerning a doctor charged with (but acquitted of) the murder of his terminally ill patient, and critically examines the criminal law of England and Wales relating to homicide in the context of medical practice. While similar issues obviously arise in many other countries, no comparative study is attempted in the paper. However, the arguments which have been presented are of more than local interest. From an analysis of this case and others, it appears that there is in common law something which can be called the doctor s defense. It holds that a doctor may, when caring for a patient who is suffering great pain, lawfully administer pain-killing drugs, despite the fact that, as the doctor well knows, one certain or highly probable consequence will be to shorten the patient s life. Current justifications for this defense are either incoherent or too weak. Some require that different conceptions of intention be deployed, depending on whether the agent is a doctor or not. Others rely on the philosophically controversial doctrine of double effect. Still others invoke an implausible notion of minimal causation. All these justifications apply readily enough to morally and factually easy cases, but fail in hard cases where the need for some justification is most pressing. These justifications seem incapable of providing adequate guidance to prosecutors or trial judges. Absent principled and transparent justification, the English criminal justice system exhibits different outcomes on what appear to be broadly similar facts. It is disturbing that the law is uncertain and incapable of giving adequate guidance. A doctor, compelled by conscience to intervene to end a person s life, should certainly be ready and willing to face rigorous legal scrutiny, but the law applied should not be arbitrary and random, nor should the outcome turn solely or chiefly on prosecutorial

  6. Modulation of Melanogenesis and Antioxidant Status of Melanocytes in Response to Phototoxic Action of Doxycycline.

    PubMed

    Rok, Jakub; Buszman, Ewa; Beberok, Artur; Delijewski, Marcin; Otręba, Michał; Wrześniok, Dorota

    2015-11-01

    Doxycycline is a commonly used tetracycline antibiotic showing the broad spectrum of antibacterial action. However, the use of this antibiotic is often connected with the risk of phototoxic reactions that lead to various skin disorders. One of the factors influencing the photosensitivity reactions is the melanin content in melanocytes. In this study, the impact of doxycycline and UVA irradiation on cell viability, melanogenesis and antioxidant defense system in cultured normal human epidermal melanocytes (HEMn-DP) was examined. The exposure of cells to doxycycline and UVA radiation resulted in concentration-dependent loss in melanocytes viability and induced melanin biosynthesis. Significant changes were stated in cellular antioxidant enzymes activity: SOD, CAT and GPx, which indicates alterations of antioxidant defense system. The results obtained in vitro may explain the mechanisms of phototoxic reactions that occur in normal human epidermal melanocytes in vivo after exposure of skin to doxycycline and UVA radiation.

  7. Antioxidants and vascular health.

    PubMed

    Bielli, Alessandra; Scioli, Maria Giovanna; Mazzaglia, Donatella; Doldo, Elena; Orlandi, Augusto

    2015-12-15

    Oxygen free radicals and other reactive oxygen species (ROS) are common products of normal aerobic cellular metabolism, but high levels of ROS lead to oxidative stress and cellular damage. Increased production of ROS favors vascular dysfunction, inducing altered vascular permeability and inflammation, accompanied by the loss of vascular modulatory function, the imbalance between vasorelaxation and vasoconstriction, and the aberrant expression of inflammatory adhesion molecules. Inflammatory stimuli promote oxidative stress generated from the increased activity of mitochondrial nicotinamide adenine dinucleotide phosphate oxidase, particularly of the Nox4 isoform, with the consequent impairment of mitochondrial β-oxidation. Vascular dysfunction due to the increase in Nox4 activity and ROS overproduction leads to the progression of cardiovascular diseases, diabetes, inflammatory bowel disease, and neurological disorders. Considerable research into the development of effective antioxidant therapies using natural derivatives or new synthetic molecules has been conducted. Antioxidants may prevent cellular damage by reducing ROS overproduction or interfering in reactions that involve ROS. Vitamin E and ascorbic acid are well known as natural antioxidants that counteract lipid peroxidative damage by scavenging oxygen-derived free radicals, thus restoring vascular function. Recently, preliminary studies on natural antioxidants such as goji berries, thymus, rosemary, green tea ginseng, and garlic have been conducted for their efficacy in preventing vascular damage. N-acetyl-cysteine and propionyl-L-carnitine are synthetic compounds that regulate ROS production by replacing endogenous antioxidants in both endothelial and smooth muscle cells. In this review, we consider the molecular mechanisms underlying the generation of oxidative stress-induced vascular dysfunction as well as the beneficial effects of antioxidant therapies.

  8. Ballistic Missile Defense System (BMDS)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-362 Ballistic Missile Defense System (BMDS) As of FY 2017 President’s Budget Defense...Estimate RDT&E - Research, Development, Test, and Evaluation SAR - Selected Acquisition Report SCP - Service Cost Position TBD - To Be Determined TY - Then

  9. Self-Defense for Teens

    ERIC Educational Resources Information Center

    Givler, Jill I.

    2005-01-01

    Resources for self-defense training programs have become more popular and available over the last few years. Introducing a self-defense unit as part of a school physical education program is a wonderful way to address a number of psychosocial issues that prevail among teenagers today. The physical skills learned in this type of program allow…

  10. Defense Acquisition Performance Assessment Report

    DTIC Science & Technology

    2006-01-01

    DAPA Project Officer” BeCKeR, gRACe CHuNg , Associate Deputy General Counsel, Office of the Secretary of Defense – “Legal view of the Processes...FiguRes Jordan, Dr. Leland G. “Systemic Fiscal Optimism in Defense Planning.” Acquisition Review Quarterly Winter 2000: 47-62. Joyce, Michael and Bettina

  11. 22 CFR 120.44 - Foreign defense article or defense service.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Foreign defense article or defense service. 120... PURPOSE AND DEFINITIONS § 120.44 Foreign defense article or defense service. Foreign defense article or defense service means any article or service described on the U.S. Munitions List of non-U.S....

  12. SDI (Strategic Defense Initiative): Myth or reality

    SciTech Connect

    Canavan, G.H.

    1988-06-01

    This report reviews previous attempts to develop strategic defenses, the technologies currently under consideration by the Strategic Defense Initiative (SDI), their main unknowns, and the likely performance of strategic defense concepts against evolving threats. 47 refs.

  13. Optimal defense theory explains deviations from latitudinal herbivory defense hypothesis.

    PubMed

    Kooyers, Nicholas J; Blackman, Benjamin K; Holeski, Liza M

    2017-04-01

    The latitudinal herbivory defense hypothesis (LHDH) postulates that the prevalence of species interactions, including herbivory, is greater at lower latitudes, leading to selection for increased levels of plant defense. While latitudinal defense clines may be caused by spatial variation in herbivore pressure, optimal defense theory predicts that clines could also be caused by ecogeographic variation in the cost of defense. For instance, allocation of resources to defense may not increase plant fitness when growing seasons are short and plants must reproduce quickly. Here we use a common garden experiment to survey genetic variation for constitutive and induced phenylpropanoid glycoside (PPG) concentrations across 35 Mimulus guttatus populations over a ~13° latitudinal transect. Our sampling regime is unique among studies of the LHDH in that it allows us to disentangle the effects of growing season length from those of latitude, temperature, and elevation. For five of the seven PPGs surveyed, we find associations between latitude and plant defense that are robust to population structure. However, contrary to the LHDH, only two PPGs were found at higher levels in low latitude populations, and total PPG concentrations were higher at higher latitudes. PPG levels are strongly correlated with growing season length, with higher levels of PPGs in plants from areas with longer growing seasons. Further, flowering time is positively correlated with the concentration of nearly all PPGs, suggesting that there may be a strong trade-off between development time and defense production. Our results reveal that ecogeographic patterns in plant defense may reflect variation in the cost of producing defense compounds in addition to variation in herbivore pressure. Thus, the biogeographic pattern predicted by the LHDH may not be accurate because the underlying factors driving variation in defense, in this case, growing season length, are not always associated with latitude in the same

  14. Antioxidants in Down syndrome.

    PubMed

    Lott, Ira T

    2012-05-01

    Individuals with Down syndrome (DS) have high levels of oxidative stress throughout the lifespan. Mouse models of DS share some structural and functional abnormalities that parallel findings seen in the human phenotype. Several of the mouse models show evidence of cellular oxidative stress and have provided a platform for antioxidant intervention. Genes that are overexpressed on chromosome 21 are associated with oxidative stress and neuronal apoptosis. The lack of balance in the metabolism of free radicals generated during processes related to oxidative stress may have a direct role in producing the neuropathology of DS including the tendency to Alzheimer disease (AD). Mitochondria are often a target for oxidative stress and are considered to be a trigger for the onset of the AD process in DS. Biomarkers for oxidative stress have been described in DS and in AD in the general population. However, intervention trials using standard antioxidant supplements or diets have failed to produce uniform therapeutic effect. This chapter will examine the biological role of oxidative stress in DS and its relationship to abnormalities in both development and aging within the disorder. This article is part of a Special Issue entitled: Antioxidants and Antioxidant Treatment in Disease.

  15. Neuroprotective antioxidants from marijuana.

    PubMed

    Hampson, A J; Grimaldi, M; Lolic, M; Wink, D; Rosenthal, R; Axelrod, J

    2000-01-01

    Cannabidiol and other cannabinoids were examined as neuroprotectants in rat cortical neuron cultures exposed to toxic levels of the neurotransmitter, glutamate. The psychotropic cannabinoid receptor agonist delta 9-tetrahydrocannabinol (THC) and cannabidiol, (a non-psychoactive constituent of marijuana), both reduced NMDA, AMPA and kainate receptor mediated neurotoxicities. Neuroprotection was not affected by cannabinoid receptor antagonist, indicating a (cannabinoid) receptor-independent mechanism of action. Glutamate toxicity can be reduced by antioxidants. Using cyclic voltametry and a fenton reaction based system, it was demonstrated that Cannabidiol, THC and other cannabinoids are potent antioxidants. As evidence that cannabinoids can act as an antioxidants in neuronal cultures, cannabidiol was demonstrated to reduce hydroperoxide toxicity in neurons. In a head to head trial of the abilities of various antioxidants to prevent glutamate toxicity, cannabidiol was superior to both alpha-tocopherol and ascorbate in protective capacity. Recent preliminary studies in a rat model of focal cerebral ischemia suggest that cannabidiol may be at least as effective in vivo as seen in these in vitro studies.

  16. Antioxidants in Down syndrome☆

    PubMed Central

    Lott, Ira T.

    2012-01-01

    Individuals with Down syndrome (DS) have high levels of oxidative stress throughout the lifespan. Mouse models of DS share some structural and functional abnormalities that parallel findings seen in the human phenotype. Several of the mouse models show evidence of cellular oxidative stress and have provided a platform for antioxidant intervention. Genes that are overexpressed on chromosome 21 are associated with oxidative stress and neuronal apoptosis. The lack of balance in the metabolism of free radicals generated during processes related to oxidative stress may have a direct role in producing the neuropathology of DS including the tendency to Alzheimer disease (AD). Mitochondria are often a target for oxidative stress and are considered to be a trigger for the onset of the AD process in DS. Biomarkers for oxidative stress have been described in DS and in AD in the general population. However, intervention trials using standard antioxidant supplements or diets have failed to produce uniform therapeutic effect. This chapter will examine the biological role of oxidative stress in DS and its relationship to abnormalities in both development and aging within the disorder. This article is part of a Special Issue entitled: Antioxidants and Antioxidant Treatment in Disease. PMID:22206998

  17. ABA Inducible Rice Protein Phosphatase 2C Confers ABA Insensitivity and Abiotic Stress Tolerance in Arabidopsis

    PubMed Central

    Singh, Amarjeet; Jha, Saroj K.; Bagri, Jayram; Pandey, Girdhar K.

    2015-01-01

    Arabidopsis PP2C belonging to group A have been extensively worked out and known to negatively regulate ABA signaling. However, rice (Oryza sativa) orthologs of Arabidopsis group A PP2C are scarcely characterized functionally. We have identified a group A PP2C from rice (OsPP108), which is highly inducible under ABA, salt and drought stresses and localized predominantly in the nucleus. Genetic analysis revealed that Arabidopsis plants overexpressing OsPP108 are highly insensitive to ABA and tolerant to high salt and mannitol stresses during seed germination, root growth and overall seedling growth. At adult stage, OsPP108 overexpression leads to high tolerance to salt, mannitol and drought stresses with far better physiological parameters such as water loss, fresh weight, chlorophyll content and photosynthetic potential (Fv/Fm) in transgenic Arabidopsis plants. Expression profile of various stress marker genes in OsPP108 overexpressing plants revealed interplay of ABA dependent and independent pathway for abiotic stress tolerance. Overall, this study has identified a potential rice group A PP2C, which regulates ABA signaling negatively and abiotic stress signaling positively. Transgenic rice plants overexpressing this gene might provide an answer to the problem of low crop yield and productivity during adverse environmental conditions. PMID:25886365

  18. ABA inducible rice protein phosphatase 2C confers ABA insensitivity and abiotic stress tolerance in Arabidopsis.

    PubMed

    Singh, Amarjeet; Jha, Saroj K; Bagri, Jayram; Pandey, Girdhar K

    2015-01-01

    Arabidopsis PP2C belonging to group A have been extensively worked out and known to negatively regulate ABA signaling. However, rice (Oryza sativa) orthologs of Arabidopsis group A PP2C are scarcely characterized functionally. We have identified a group A PP2C from rice (OsPP108), which is highly inducible under ABA, salt and drought stresses and localized predominantly in the nucleus. Genetic analysis revealed that Arabidopsis plants overexpressing OsPP108 are highly insensitive to ABA and tolerant to high salt and mannitol stresses during seed germination, root growth and overall seedling growth. At adult stage, OsPP108 overexpression leads to high tolerance to salt, mannitol and drought stresses with far better physiological parameters such as water loss, fresh weight, chlorophyll content and photosynthetic potential (Fv/Fm) in transgenic Arabidopsis plants. Expression profile of various stress marker genes in OsPP108 overexpressing plants revealed interplay of ABA dependent and independent pathway for abiotic stress tolerance. Overall, this study has identified a potential rice group A PP2C, which regulates ABA signaling negatively and abiotic stress signaling positively. Transgenic rice plants overexpressing this gene might provide an answer to the problem of low crop yield and productivity during adverse environmental conditions.

  19. A Comprehensive Proteomic Survey of ABA-Induced Protein Phosphorylation in Rice (Oryza sativa L.)

    PubMed Central

    Qiu, Jiehua; Hou, Yuxuan; Wang, Yifeng; Li, Zhiyong; Zhao, Juan; Tong, Xiaohong; Lin, Haiyan; Wei, Xiangjin; Ao, Hejun; Zhang, Jian

    2017-01-01

    abscisic acid (ABA) is a key phytohormone regulating plant development and stress response. The signal transduction of ABA largely relies on protein phosphorylation. However; little is known about the phosphorylation events occurring during ABA signaling in rice thus far. By employing a label-free; MS (Mass Spectrometry)-based phosphoproteomic approach; we identified 2271 phosphosites of young rice seedlings and their intensity dynamics in response to ABA; during which 1060 proteins were found to be differentially phosphorylated. Western-blot analysis verified the differential phosphorylation pattern of D1, SMG1 and SAPK9 as indicated by the MS result; suggesting the high reliability of our phosphoproteomic data. The DP (differentially phosphorylated) proteins are extensively involved in ABA as well as other hormone signaling pathways. It is suggested that ABA antagonistically regulates brassinosteroid (BR) signaling via inhibiting BR receptor activity. The result of this study not only expanded our knowledge of rice phosphoproteome, but also shed more light on the pattern of protein phosphorylation in ABA signaling. PMID:28054942

  20. Curcumin attenuates CFA induced thermal hyperalgesia by modulation of antioxidant enzymes and down regulation of TNF-α, IL-1β and IL-6.

    PubMed

    Singh, Ajeet Kumar; Vinayak, Manjula

    2015-03-01

    Reactive oxygen species are signaling mediators of nociceptive pathways. Exogenous administrations of antioxidants show anti-hyperalgesic effect. However, very little is known about the role of endogenous antioxidant defense system in pain pathology. Curcumin is a dietary antioxidant which shows ameliorative effect on thermal hypersensitivity, however detailed study is lacking. Present study was aimed to analyze the changes in oxidative stress, modulation of antioxidant enzymes and pro-inflammatory cytokines in complete Freund's adjuvant induced inflammatory hyperalgesia and the effect of curcumin on antioxidant defense system and pro-inflammatory cytokines. Anti-hyperalgesic activity of curcumin was evidenced after 6 h of treatment. Oxidative stress was evidenced in paw skin and spinal cord of hyperalgesic rats by high level of lipid peroxidation. A decrease in activity of antioxidant enzymes like catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase and an increase in level of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 in paw skin was observed as compared to normal rats. However, activity of antioxidant enzymes was enhanced in spinal cord. The changes were brought towards normal level after curcumin treatment. The results suggest that modulation of antioxidant defense system is early event in initiation of inflammatory hyperalgesia which might lead to initiation of other signaling pathways mediated by lipid peroxide, TNF-α, IL-1β and IL-6. Decrease in oxidative stress and down regulation of these cytokines by curcumin is suggested to be involved in its anti-hyperalgesic effect.

  1. Oxidant and antioxidant status of cadmium administered rats

    NASA Astrophysics Data System (ADS)

    Toplan, S.; Ozcelik, D.; Dariyerli, N.; Akyolcu, M. C.

    2003-05-01

    Cadmium is one of the industrial elements that lead environmental pollution. Biological half-life of cadmium is relatively longer, so its clearance from tissue is considerably long. In present study, oxidant stress and antioxidant defense mechanism due to exposure to cadmium in rats wanted to be investigated. For such a purpose adult female wistar albino rats were divided into two as control and experimental groups. During experimental period while both group animals were fed by standard fodder, cadmium added (20 μg Cd/ml as cadmium sulfate) drinking water was given to experimental group for four weeks. At the end of four weeks blood samples were drawn from animals under ether anesthesia. As a Last product of lipid peroxidation malondialdehyde (MDA) level, superoxide dismutas (SOD) activity which is sign of antioxidant defense enzyme activity and glutathione levels (GSH) were measured. Increase in lipid peroxidation has been observed by increased MDA levels in experimental group (p<0.001). SOD enzyme activity was also found to be significantly lower in experimental group (p<0.001). Glutathione level of experimental group found to be decreased according to control group values (p<0.01). As a result of present study it may be concluded that cadmium may lead to increase in lipid peroxidation. On the other hand SOD activity and glutathione levels may also be decreased by effect of cadmium in erythrocytes. So the resultant would be the disturbed antioxidant mechanism

  2. Cytokine and Antioxidant Regulation in the Intestine of the Gray Mouse Lemur (Microcebus murinus) During Torpor.

    PubMed

    Tessier, Shannon N; Katzenback, Barbara A; Pifferi, Fabien; Perret, Martine; Storey, Kenneth B

    2015-04-01

    During food shortages, the gray mouse lemur (Microcebus murinus) of Madagascar experiences daily torpor thereby reducing energy expenditures. The present study aimed to understand the impacts of torpor on the immune system and antioxidant response in the gut of these animals. This interaction may be of critical importance given the trade-off between the energetically costly immune response and the need to defend against pathogen entry during hypometabolism. The protein levels of cytokines and antioxidants were measured in the small intestine (duodenum, jejunum, and ileum) and large intestine of aroused and torpid lemurs. While there was a significant decrease of some pro-inflammatory cytokines (IL-6 and TNF-α) in the duodenum and jejunum during torpor as compared to aroused animals, there was no change in anti-inflammatory cytokines. We observed decreased levels of cytokines (IL-12p70 and M-CSF), and several chemokines (MCP-1 and MIP-2) but an increase in MIP-1α in the jejunum of the torpid animals. In addition, we evaluated antioxidant response by examining the protein levels of antioxidant enzymes and total antioxidant capacity provided by metabolites such as glutathione (and others). Our results indicated that levels of antioxidant enzymes did not change between torpor and aroused states, although antioxidant capacity was significantly higher in the ileum during torpor. These data suggest a suppression of the immune response, likely as an energy conservation measure, and a limited role of antioxidant defenses in supporting torpor in lemur intestine.

  3. Self-supplementation and effects of dietary antioxidants during acute thermal stress.

    PubMed

    Beaulieu, Michaël; Haas, Anabel; Schaefer, H Martin

    2014-02-01

    Thermal stress leads to increased production of reactive oxygen species. If an organism is not able to simultaneously mount an efficient antioxidant defense system, this may lead to increased oxidative damage, which is potentially deleterious in terms of health and fitness. Exposure to cold or heat is therefore expected to be associated with a high demand for antioxidants. In agreement, several studies have shown that supplementing the diet of thermally stressed organisms with antioxidants leads to a reduction of oxidative damage. However, whether organisms can actively supplement their diet with antioxidants to alleviate temperature-induced oxidative damage is unknown. Here, we show that captive Gouldian finches (Erythrura gouldiae) supplement their diet more with seeds rich in antioxidants below than within their thermoneutral zone. Moreover, having access to seeds rich in antioxidants at temperatures below thermoneutrality decreases their oxidative damage. These results indicate that, when facing a thermal challenge, animals are able to take advantage of the antioxidant properties of their food to improve their oxidative balance. Having access to food resources rich in antioxidants may therefore be of primary importance for organisms in their natural habitat, as it may help them to cope with oxidative constraints due to challenging temperature regimes.

  4. Scuba diving activates vascular antioxidant system.

    PubMed

    Sureda, A; Batle, J M; Ferrer, M D; Mestre-Alfaro, A; Tur, J A; Pons, A

    2012-07-01

    The aim was to study the effects of scuba diving immersion on plasma antioxidant defenses, nitric oxide production, endothelin-1 and vascular endothelial growth factor levels. 9 male divers performed an immersion at 50 m depth for a total time of 35 min. Blood samples were obtained before diving at rest, immediately after diving, and 3 h after the diving session. Leukocyte counts, plasma 8oxoHG, malondialdehyde and nitrite levels significantly increased after recovery. Activities of lactate dehydrogenase, creatine kinase, catalase and superoxide significantly increased immediately after diving and these activities remained high after recovery. Plasma myeloperoxidase activity and protein levels and extracellular superoxide dismutase protein levels increased after 3 h. Endothelin-1 concentration significantly decreased after diving and after recovery. Vascular endothelial growth factor concentration significantly increased after diving when compared to pre-diving values, returning to initial values after recovery. Scuba diving at great depth activated the plasma antioxidant system against the oxidative stress induced by elevated pO₂ oxygen associated with hyperbaria. The decrease in endothelin-1 levels and the increase in nitric oxide synthesis could be factors that contribute to post-diving vasodilation. Diving increases vascular endothelial growth factor plasma levels which can contribute to the stimulation of tissue resistance to diving-derived oxidative damage.

  5. Cellular defense mechanisms against lead toxicity in the vascular system.

    PubMed

    Shinkai, Yasuhiro; Kaji, Toshiyuki

    2012-01-01

    Lead is a toxic heavy metal that can cause a range of health problems. In this context, the vascular system is a particular target of the deleterious effects of lead. Lead exerts its toxicity through substitution of other divalent cations such as calcium and zinc, resulting in disruption of homeostasis. Based on the evidence that lead up-regulates endoplasmic reticulum (ER) chaperone glucose-regulated protein 78 (GRP78) and/or antioxidant proteins such as hemeoxygenase-1, it is believed that the heavy metal is able to induce ER and/or oxidative stress in cells. These events also suggest that the unfolded protein response (UPR) system and the antioxidant defense system Kelch-like ECH-associated protein 1-nuclear factor (NF)-E2-related factor 2 (Keap1-Nrf2) play a critical role in adaptive response to lead. In this review, we summarize recent progress in lead toxicity in terms of cellular defense systems, including stress proteins and transcription factors involved in the vascular system.

  6. Heavy Metal Stress and Some Mechanisms of Plant Defense Response

    PubMed Central

    Emamverdian, Abolghassem; Ding, Yulong; Mokhberdoran, Farzad; Xie, Yinfeng

    2015-01-01

    Unprecedented bioaccumulation and biomagnification of heavy metals (HMs) in the environment have become a dilemma for all living organisms including plants. HMs at toxic levels have the capability to interact with several vital cellular biomolecules such as nuclear proteins and DNA, leading to excessive augmentation of reactive oxygen species (ROS). This would inflict serious morphological, metabolic, and physiological anomalies in plants ranging from chlorosis of shoot to lipid peroxidation and protein degradation. In response, plants are equipped with a repertoire of mechanisms to counteract heavy metal (HM) toxicity. The key elements of these are chelating metals by forming phytochelatins (PCs) or metallothioneins (MTs) metal complex at the intra- and intercellular level, which is followed by the removal of HM ions from sensitive sites or vacuolar sequestration of ligand-metal complex. Nonenzymatically synthesized compounds such as proline (Pro) are able to strengthen metal-detoxification capacity of intracellular antioxidant enzymes. Another important additive component of plant defense system is symbiotic association with arbuscular mycorrhizal (AM) fungi. AM can effectively immobilize HMs and reduce their uptake by host plants via binding metal ions to hyphal cell wall and excreting several extracellular biomolecules. Additionally, AM fungi can enhance activities of antioxidant defense machinery of plants. PMID:25688377

  7. Heavy metal stress and some mechanisms of plant defense response.

    PubMed

    Emamverdian, Abolghassem; Ding, Yulong; Mokhberdoran, Farzad; Xie, Yinfeng

    2015-01-01

    Unprecedented bioaccumulation and biomagnification of heavy metals (HMs) in the environment have become a dilemma for all living organisms including plants. HMs at toxic levels have the capability to interact with several vital cellular biomolecules such as nuclear proteins and DNA, leading to excessive augmentation of reactive oxygen species (ROS). This would inflict serious morphological, metabolic, and physiological anomalies in plants ranging from chlorosis of shoot to lipid peroxidation and protein degradation. In response, plants are equipped with a repertoire of mechanisms to counteract heavy metal (HM) toxicity. The key elements of these are chelating metals by forming phytochelatins (PCs) or metallothioneins (MTs) metal complex at the intra- and intercellular level, which is followed by the removal of HM ions from sensitive sites or vacuolar sequestration of ligand-metal complex. Nonenzymatically synthesized compounds such as proline (Pro) are able to strengthen metal-detoxification capacity of intracellular antioxidant enzymes. Another important additive component of plant defense system is symbiotic association with arbuscular mycorrhizal (AM) fungi. AM can effectively immobilize HMs and reduce their uptake by host plants via binding metal ions to hyphal cell wall and excreting several extracellular biomolecules. Additionally, AM fungi can enhance activities of antioxidant defense machinery of plants.

  8. Public-Private Partnerships in Defense Acquisition Programs-Defensible?

    DTIC Science & Technology

    2009-12-01

    Ministry of Defence (Singapore) MOD Ministry of Defence (UK) xii MRO maintenance, repair and overhaul NAO National Accounting Office (UK) NPV net...in 2002). Similarly, in Australia—one of the early trend setters for PPPs—the implementation of defense PPPs by the Defense Material Organisation...wide range of systems and equipment, and material and services for those systems and equipment...The systems and equipment include vehicles, ships

  9. Strategic defense initiative

    SciTech Connect

    Nichols, J.P.

    1985-01-01

    The Engineering Technology Division has a leading role, including that of program management, in a major new programmatic thrust of the Oak Ridge National Laboratory that is in support of the national Strategic Defense Initiative (SDI). It is appropriate for the Laboratory to become significantly involved in the program because several of the most promising SDI technologies are in areas for which ORNL (together with Y-12 and K-25) have strong capabilities and significant resources. The initial ORNL work in support of the SDI program is focused on three technologies in which ORNL has extensive experience and traditionally strong research and development programs: (1) space nuclear power, (2) flywheel energy storage, and (3) neutral particle beams. The space nuclear program will utilize our capabilities in areas such as refractory materials, high-temperature alkali metal systems, shielding, and instrumentation. Space nuclear reactors capable of supplying multimegawatt levels of electrical power on a continuous and long-term basis are envisioned to be required for a variety of SDI surveillance satellites and space-borne weapons platforms. The feasibility of an alkali metal Rankine power conversion cycle, which has promise of providing high power with a very low system mass, is planned for study.

  10. Gastroduodenal Mucosal Defense Mechanisms

    PubMed Central

    Said, Hyder; Kaji, Izumi; Kaunitz, Jonathan D.

    2015-01-01

    Purpose of Review To highlight recent developments in the field of gastroduodenal mucosal defense with emphasis on lumen-gut interactions. Recent Findings There has been a growing interest in the physiological functions of luminal chemosensors present from tongue to colon that detect organic molecules in the luminal content associated with nutrient ingestion, usually associated with specialized cells, in particular the enteroendocrine cells. These receptors transduce the release of peptide hormones, in particular proglucagon-derived products such as the glucagon-like-peptides (GLPs), which have profound effects on gut function and on metabolism. Luminal chemosensors transduce GLP release in response to changes in the cellular environment, as part of the mechanism of nutrient chemosensing. GLP-2 has important trophic effects on the intestinal mucosa, including increasing the proliferation rate of stem cells and reducing transmucosal permeability to ions and small molecules, in addition to increasing the rate of duodenal bicarbonate secretion. GLP-1, although traditionally considered an incretin that enhances the effect of insulin on peripheral tissues, also has trophic effects on the intestinal epithelium. Summary A better understanding of the mechanisms that mediate GLP release can further illuminate the importance of nutrient chemosensing as an important component of the mechanism that mediates the trophic effects of luminal nutrients. GLP-1 and -2 are already in clinical use for the treatment of diabetes and intestinal failure. Improved understanding of the control of their release and their end-organ effects will identify new clinical indications and interventions that enhance their release. PMID:26376476

  11. How to Overcome Defensive Communications

    ERIC Educational Resources Information Center

    Cross, Gary P.

    1978-01-01

    After discussing the defensive response in interpersonal communications in organizations, the article presents eight communication techniques for improving organizational communication skills and thereby creating a more supportive organizational climate. (MF)

  12. Strategic Defense Initiative - an overview

    SciTech Connect

    Abrahamson, J.A.

    1985-01-01

    A general framework for developing the concept and implementing options for strategic ballistic missile defense systems is emerging. The objective of the Strategic Defense Initiative (SDI) program is to conduct research on those technologies for defensive system which could intercept ballistic missiles after they have been launched and prevent them from hitting their targets. Its goal is to acquire the technical knowledge as a basis for a later decision on deployment, not a program for deployment or star wars. Abrahamson reviews the basic technological questions facing researchers, outlines the multi-layered defense possibilities and summarizes the status of technology to date. He argues for a continuity of resources to conduct the program. 4 figures.

  13. Theater Missile Defense Integration Issues

    DTIC Science & Technology

    1993-06-01

    high endoatmospheric defense interceptor (HEDI) proposed t earlier. EADTB. Extended Air Defense Test Bed. A computer-based analysis center for...for attacking deeper elements of an aggressors’s ground forces. Known in NATO as Follow-on Force Attack ( FOFA ). JSTARS. Joint surveillance target...AFIA/INKS ATTN. INKS AFIS/INT ATTN: INT AIR hORCE CTR FOR STUDIES & ANALYSIS ATTN: AFSAA/SAKI 9 Dist-1 w^mmmm mmmm^-mmmemH

  14. US Home Defense Forces Study

    DTIC Science & Technology

    1981-03-01

    Groups and Length of Service. ....... . . . 69 Figure 16- Connecticut State Guard Personnel, 1940-1945 - Losses August 1940-1944...sought authority to form a cohesive group . In the East mayors, businessmen, and professionals formed Committees for Public Safety, Home Defense...forces that could apply for such support was as shown in Figure 2. The difficulty of grouping the various types of home defense forces in the 48 states in

  15. 77 FR 10976 - Defense Federal Acquisition Regulation Supplement; Technical Amendment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Part 252 Defense Federal Acquisition Regulation Supplement; Technical Amendment AGENCY: Defense Acquisition Regulations System, Department of Defense (DoD)....

  16. 78 FR 30232 - Defense Federal Acquisition Regulation Supplement; Technical Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Parts 204 and 252 Defense Federal Acquisition Regulation Supplement; Technical Amendments AGENCY: Defense Acquisition Regulations System, Department of Defense...

  17. 78 FR 41331 - Defense Federal Acquisition Regulation Supplement; Technical Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Part 225 Defense Federal Acquisition Regulation Supplement; Technical Amendments AGENCY: Defense Acquisition Regulations System, Department of Defense (DoD)....

  18. 76 FR 13297 - Defense Federal Acquisition Regulation Supplement; Technical Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Part 215 Defense Federal Acquisition Regulation Supplement; Technical Amendments AGENCY: Defense Acquisition Regulations System, Department of Defense (DoD)....

  19. [Oxidative injury and its defense system in vivo].

    PubMed

    Niwa, Y

    1999-03-01

    We and other researchers verified that excessively produced free radicals by neutrophils induce various diseases such as Behçet's disease, MCLS, SLE (neutrophil-stimulated lymphocytes), RA (synovial fluid neutrophils), Crohn's disease, colitis ulcerosa, and dermatitis herpetiformis (Dühring). Recently, it was reported that environmental toxic agents including herbicides such as paraquat, insecticides, nitrogen oxide, and ultraviolet radiation produce free radicals. Nitrogen oxide, a main product of the combustion of petroleum, is a prominent component of exhaust from automobiles. Generation of 1O2 by ultraviolet radiation has also increased by breaks in the earth's ozone layer induced by halogenated hydrocarbon gas. Various diseases have been induced by these agents such as malignancies, severe adult atopic dermatitis, complication of cataract and retinolysis with atopic dermatitis, skin cancer, male infertility, severe collagen diseases, and lung fibrosis. It was also found that PCB, methyl-Hg and Mn, Cd induce neuropathic diseases through the increase in free radical production. On the other hand, a self-defense system exists against oxidative injuries; high-molecular-weight antioxidants such as SOD, catalase, and GSH-Px, and low-molecular-weight antioxidants such as vitamin C, E, A, polyphenols, flavonoids, and catechin. As protection from oxidative injury, various antioxidant products have been developed, however, the development of SOD injection was given up by all the pharmaceutical companies in the world on account of ineffectiveness due to rapid excretion from the kidney, low affinity to the receptor and weak penetration into the cell. A.M. Michelson, a French biochemist succeeded in developing an effective bovine liposomal-encapsulated SOD solving these problems, however, he also gave it up since French government prohibited bovine products due to the prion virus. Regarding low-molecular-weight antioxidants, synthetic products generally show low affini