Showing papers on "Catalase published in 2008"
TL;DR: Resveratrol could be a useful drug for the protection of liver cells from oxidative stress induced damage and is shown to have many biological properties, including antioxidant activity.
298 citations
TL;DR: It is concluded that ROS modulate An.
273 citations
TL;DR: It is shown that antioxidant enzymes, including superoxide dismutase 1 and 2, catalase, and heme oxygenase 1, are markedly upregulated in active demyelinating MS lesions compared to normal-appearing white matter and white matter tissue from nonneurological control brains.
265 citations
TL;DR: Data indicate that the protective role of proline has to be considered minimal as its accumulation was inversely correlated with tolerance to the stress, and the early accumulation of MDA seems to be associated to an impaired ability for H2O2 scavenging.
Abstract: Soil flooding constitutes a seasonal factor that negatively affects plant performance and crop yields. In this work, the relationship between oxidative damage and flooding sensitivity was addressed in three citrus genotypes with different abilities to tolerate waterlogging. We examined leaf visible damage, oxidative damage in terms of malondialdehyde (MDA) concentration, leaf proline concentration, leaf and root ascorbate and glutathione contents and the antioxidant enzyme activities superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11), catalase (EC 1.11.1.6) and glutathione reductase (EC 1.8.1.7). No differences in the extent of oxidative damage relative to controls were found among genotypes. However, a different ability to delay the apparition of oxidative damage was associated to a higher tolerance to waterlogging. This ability was linked to an enhanced activated oxygen species' scavenging capacity in terms of an increased antioxidant enzyme activity and higher content in polar antioxidant compounds. Therefore, the existence of a direct relationship between stress sensitivity and the early accumulation of MDA is proposed. In addition, data indicate that the protective role of proline has to be considered minimal as its accumulation was inversely correlated with tolerance to the stress. The positive antioxidant response in Carrizo citrange (Poncirus trifoliata L. Raf. x Citrus sinensis L. Osb.) and Citrumelo CPB 4475 (Poncirus trifoliata L. Raf. x Citrus paradisi L. Macf.) might be responsible for a higher tolerance to flooding stress, whereas in Cleopatra mandarin (Citrus reshni Hort. Ex Tan.), the early accumulation of MDA seems to be associated to an impaired ability for H2O2 scavenging.
260 citations
TL;DR: In this article, the effects of salicylic acid (SA) on manganese toxicity in cucumber plants (Cucumis sativus L.) were studied by investigating the symptoms, plant growth, lipid peroxidation, antioxidative enzymes and antioxidants.
260 citations
TL;DR: In this article, exogenous nitric oxide (NO) supplementation as sodium nitroprusside (SNP) has any ameliorating action against Cd-induced oxidative damage in plant roots.
246 citations
TL;DR: The presence of Se in medium prevented changes in the DNA methylation pattern triggered in rape seedlings by high Cd concentrations, and removal of Cd from metabolically active cellular sites and reduction of oxygen radicals were considered.
244 citations
TL;DR: SA is identified as a novel regulator of aquaporins, and an ROS-dependent signalling pathway in the roots of Arabidopsis is delineated, which involves an H(2)O(2)-induced internalization of PIPs, to downregulate root water transport.
Abstract: The water uptake capacity of plant roots (i.e. their hydraulic conductivity, Lp r ) is determined in large part by aquaporins of the plasma membrane intrinsic protein (PIP) subfamily. In the present work, we investigated two stimuli, salicylic acid (SA) and salt, because of their ability to induce an accumulation of reactive oxygen species (ROS) and an inhibition of Lp r concomitantly in the roots of Arabidopsis plants. The inhibition of Lp r by SA was partially counteracted by preventing the accumulation of hydrogen peroxide (H 2 O 2 ) with exogenous catalase. In addition, exogenous H 2 O 2 was able to reduce Lp r by up to 90% in <15 min. Based on the lack of effects of H 2 O 2 on the activity of individual aquaporins in Xenopus oocytes, and on a pharmacological dissection of the action of H 2 O 2 on Lp r , we propose that ROS do not gate Arabidopsis root aquaporins through a direct oxidative mechanism, but rather act through cell signalling mechanisms. Expression in transgenic roots of PIP-GFP fusions and immunogold labelling indicated that external H 2 O 2 enhanced, in <15 min, the accumulation of PIPs in intracellular structures tentatively identified as vesicles and small vacuoles. Exposure of roots to SA or salt also induced an intracellular accumulation of the PIP-GFP fusion proteins, and these effects were fully counteracted by co-treatment with exogenous catalase. In conclusion, the present work identifies SA as a novel regulator of aquaporins, and delineates an ROS-dependent signalling pathway in the roots of Arabidopsis. Several abiotic and biotic stress-related stimuli potentially share this path, which involves an H 2 O 2 -induced internalization of PIPs, to downregulate root water transport.
242 citations
TL;DR: The in vitro dose-dependent quenching of O(2)(-) and H(2)O(2), indicating that nano-Pt is a more potent SOD/catalase mimetic than EUK-8, prolonged the worm lifespan, regardless of thermotolerance or dietary restriction.
220 citations
TL;DR: Evidence was provided that Al comparable to biotic stress induced oxidative burst at the cell surface through up- or down-regulation of some of the key enzymes of oxidative metabolism ultimately resulting in oxidative stress leading to DNA damage and cell death in root cells of A. cepa.
213 citations
TL;DR: Ex vivo Sirt1 constitutes a determinant of renal tubular cell apoptosis by regulating cellular ROS levels and by preventing the depletion of ROS required for cell survival by regulating catalase expression.
TL;DR: The hypothesis that Bt infection increases the level of oxidative stress in the larval midgut in Galleria mellonella larvae is confirmed and it seems possible that oxidative damage contributes to cell death in the midGut during bacteriosis.
Abstract: Bacillus thuringiensis is one of the most widely used sources of biorational pesticides, as well as a key source of genes for transgenic expression to provide pest resistance in plants. In this study the effect of Bacillus thuringiensis ssp. galleriae (Bt) infection on the activity of superoxide dismutase (SOD), glutathione S-transferase (GST), catalase (CAT), concentrations of oxidated and reduced thiols (RSSR/RSH) and malondialdehyde (MDA) was tested in the midgut of Galleria mellonella larvae. We found that Bt infection resulted in increased activities of SOD, GST, malondialdehyde and RSSR/RSH ratio the first day after inoculation. However, catalase activity decreased on the first and following days after bacterial infection by Bt. Our results confirm the hypothesis that Bt infection increases the level of oxidative stress in the larval midgut. In light of this study, it seems possible that oxidative damage contributes to cell death in the midgut during bacteriosis.
TL;DR: The results indicate that the increased levels of O2- and H( 2)O(2) under Hg stress were closely linked to the improved capacity of antioxidant enzymes.
TL;DR: The results suggest that the network of transcriptional control explains how CATs and other scavenger enzymes such as peroxidase and superoxide dismutase may be coordinately regulated during development, but differentially expressed in response to different stresses for controlling ROS homeostasis.
Abstract: In Arabidopsis, catalase (CAT) genes encode a small family of proteins including CAT1, CAT2 and CAT3, which catalyze the decomposition of hydrogen peroxide (H2O2) and play an important role in controlling homeostasis of reactive oxygen species (ROS) Here, we analyze the expression profiles and activities of three catalases under different treatments including drought, cold, oxidative stresses, abscisic acid and salicylic acid in Arabidopsis Our results reveal that CAT1 is an important player in the removal of H2O2 generated under various environmental stresses CAT2 and CAT3 are major H2O2 scavengers that contribute to ROS homeostasis in light or darkness, respectively In addition, CAT2 is activated by cold and drought stresses and CAT3 is mainly enhanced by abscisic acid and oxidative treatments as well as at the senescence stage These results, together with previous data, suggest that the network of transcriptional control explains how CATs and other scavenger enzymes such as peroxidase and superoxide dismutase may be coordinately regulated during development, but differentially expressed in response to different stresses for controlling ROS homeostasis
TL;DR: In this paper, Indian ginseng (Withania somnifera L. Dunal), a medicinally important plant exposed to different concentrations of CuSO 4 (0, 10, 25, 50, 100 and 200μm) for 30 d in vitro accumulated high amount of Cu in a concentration manner.
TL;DR: Gobindobhog is reflected as a salt-sensitive cultivar, susceptible to high-stress-induced growth-inhibition, ion imbalances, membrane/oxidative damages with lower expression of stress-tolerant genes.
Abstract: In an attempt to understand the molecular basis of salt-stress response in the aromatic rice Gobindobhog, a comprehensive analysis encompassing physiological or biochemical assays and gene expression studies under high salt (200 mM NaCl) supply regimes were initiated and compared with a salt-sensitive (M-1-48) and salt-tolerant (Nonabokra) rice. The detrimental effects of salinity stress were the most pronounced in Gobindobhog, as reflected by the maximally increased root to shoot ratio, the highest chlorophyll degeneration, the highest foliar concentration of Na+ ions and peroxide content, with their maximum increment after salt treatment. The amplification of oxidative damages was further stimulated by the accumulation of putrescine and lipid peroxidation-derived toxic degradation products (increased malondialdehyde and lipoxygenase activity), which were comparable in M-1-48 and Gobindobhog. Antioxidants like anthocyanin and particularly cysteine and the osmolytes like reducing sugar, proline and polyamines (spermidine and spermine) showed the highest level in Nonabokra. While the inhibition of catalase activity occurred in all the varieties following salt-stress, the maximum induction in guaiacol peroxidase activity, elevated cysteine and proline levels in Gobindobhog probably constituted the detoxification mechanism obligatory for its survival. Intensification of the aroma content with salt treatment was markedly noted in Gobindobhog. A very low abundance of Rab16A/SamDC transcript and the corresponding proteins were observed both in M-1-48 and Gobindobhog, induced only after salt-stress, whereas they were constitutively expressed in Nonabokra. Thus, our data reflect Gobindobhog as a salt-sensitive cultivar, susceptible to high-stress-induced growth-inhibition, ion imbalances, membrane/oxidative damages with lower expression of stress-tolerant genes.
TL;DR: The functional properties of Prx2 are discussed and its role as a major component of the erythrocyte antioxidant system is discussed, which can act as a noncatalytic scavenger of hydrogen peroxide and a sink for hydrogenperoxide before turnover becomes limiting.
Abstract: Peroxiredoxin 2 (Prx2) is an antioxidant enzyme that uses cysteine residues to decompose peroxides. Prx2 is the third most abundant protein in erythrocytes, and competes effectively with catalase and glutathione peroxidase to scavenge low levels of hydrogen peroxide, including that derived from hemoglobin autoxidation. Low thioredoxin reductase activity in the erythrocyte is able to keep up with this basal oxidation and maintain the Prx2 in its reduced form, but exposure to exogenous hydrogen peroxide causes accumulation of the disulfide-linked dimer. The high cellular concentration means that although turnover is slow, erythrocyte Prx2 can act as a noncatalytic scavenger of hydrogen peroxide and a sink for hydrogen peroxide before turnover becomes limiting. The consequences of Prx2 oxidation for the erythrocyte are not well characterized, but mice deficient in this protein develop severe hemolytic anemia associated with Heinz body formation. Prx2, also known as calpromotin, regulates ion transport by associating with the membrane and activating the Gardos channel. How Prx2 redox transformations are linked to membrane association and channel activation is yet to be established. In this review, we discuss the functional properties of Prx2 and its role as a major component of the erythrocyte antioxidant system.
TL;DR: PAs are able to moderate the activities of scavenging system enzymes and to influence oxidative stress intensity and Hydrogen peroxide and superoxide radical contents were reduced in stressed plants after Spd pretreatment.
TL;DR: The results reveal that Foxo3a can inhibit hypertrophy by transcriptionally targeting catalase and identified that myocardin was a downstream mediator of ROS in conveying the hypertrophic signal of insulin or insulin-like growth factor-1.
TL;DR: Assays to measure oxidative damage and cloned genes encoding two key antioxidant enzymes, superoxide dismutase and catalase, demonstrated that the Antarctic midge is highly resistant to oxidative stress.
TL;DR: The results suggest that the ascorbate-deficient mutant vtc1 is more sensitive to supplementary UV-B treatment than WT plants and asCorbate can be considered an important antioxidant forUV-B radiation.
TL;DR: It can be concluded that the water deficit areas may be well used for the cultivation of medicinal plants like C. roseus and the economically important alkaloid production can be enhanced in the plant level.
TL;DR: In this article, salicylic acid (SA) was used to prevent hydrogen peroxide and malondialdehyde accumulation and the increase in superoxide dismutase during storage of navel oranges.
TL;DR: Results indicate that heat shock-induced ROS is promoted via NADPH oxid enzyme, xanthine oxidase, and mitochondria, which may play an important role in the heatshock-induced activation of MAPKs, which can induce MMP-1 and-9 expressions.
TL;DR: The results suggest that antioxidant enzymes play important roles in the physiological changes related to metabolism and cell protection that occur in Pacific oysters exposed to Cd.
Abstract: Cadmium (Cd) is one of the most toxic heavy metal pollutants in the aquatic environment and can induce the formation of reactive oxygen species (ROS) that cause oxidative stress. In present study, we cloned catalase (CAT) and glutathione peroxidase (GPX) cDNA, and investigated its time- and dose-related effects of three Cd concentrations (0.01, 0.05 or 0.1 ppm) on mRNA levels of antioxidant enzymes (superoxide dismutase (SOD), CAT, GPX) in the gill and changes enzyme levels in the hemolymph of the Pacific oyster, Crassostrea gigas. The cDNA indentified encoded proteins of 516 and 244 amino acids corresponding to CAT and GPX, respectively. BLAST analysis from other species indicated that the residues essential to the enzymatic function of CAT and GPX proteins of C. gigas are highly conserved. Cd treatment significantly increased antioxidant enzyme mRNA expression in the gill in a time- and dose-dependent manner. The mRNA expression at 0.1 ppm Cd concentration increased up to 3 days (CAT, GPX) or 7 days (SOD) and then decreased by 7 days (CAT, GPX) or 11 days (SOD). Aspartate aminotransferase, alanine amintransferase and hydrogen peroxide (H2O2) concentrations levels increased significantly with exposure to 0.05 or 0.1 ppm Cd for 7 days. These results suggest that antioxidant enzymes play important roles in the physiological changes related to metabolism and cell protection that occur in Pacific oysters exposed to Cd.
TL;DR: The modified CUPRAC (cupric ion reducing antioxidant capacity) assay proved to be efficient for ascorbic acid, gallic acid and chlorogenic acid, for which the deoxyribose assay test is basically nonresponsive.
TL;DR: Coronatine might reduce the production of reactive oxygen species by activating antioxidant enzymes and DPPH-radical scavenging, thereby preventing membrane peroxidation and denaturation of biomolecules.
TL;DR: In this article, the authors evaluated the effect of 0.5, 1 and 2 µmol L−1 NO aqueous solutions to alleviate the damage caused by reactive oxygen species (ROS) in kiwifruit during storage.
Abstract: BACKGROUND: The accumulation of reactive oxygen species (ROS) in kiwifruit can cause oxidative damage during storage. Little research has been carried out on the effects of nitric oxide (NO) on oxidative damage to kiwifruit. Therefore the aim of the present study was to evaluate the ability of 0.5, 1 and 2 µmol L−1 NO aqueous solutions to alleviate oxidative damage to kiwifruit during storage. RESULTS: The most marked effect was obtained with 1 µmol L−1 NO solution, which significantly reduced the accumulation of malondialdehyde, superoxide and hydrogen peroxide, delayed the decrease in vitamins C and E, maintained the content of soluble solids, inhibited the activity of lipoxygenase and peroxidase and increased the activity of superoxide dismutase and catalase in kiwifruit during storage. The 0.5 µmol L−1 NO solution was too weak to significantly affect the content of ROS and the activity of enzymes. However, treatment with 2 µmol L−1 NO solution promoted the accumulation of ROS, decreased the activity of antioxidant enzymes and accelerated peroxidation in kiwifruit during storage. CONCLUSION By increasing the activity of antioxidant enzymes and maintaining the content of vitamins C and E, treatment with 1 µmol L−1 NO aqueous solution could protect kiwifruit against oxidative damage caused by ROS during storage. Copyright © 2008 Society of Chemical Industry
TL;DR: A role of thiamine metabolism in the plant response to environmental stress is suggested and a moderate increase in the activity of transketolase, one of the major TDP-dependent enzymes, was detectable under conditions of salt and oxidative stress.
Abstract: The responses of plants to abiotic stress involve the up-regulation of numerous metabolic pathways, including several major routes that engage thiamine diphosphate (TDP)-dependent enzymes. This suggests that the metabolism of thiamine (vitamin B1) and its phosphate esters in plants may be modulated under various stress conditions. In the present study, Zea mays seedlings were used as a model system to analyse for any relation between the plant response to abiotic stress and the properties of thiamine biosynthesis and activation. Conditions of drought, high salt, and oxidative stress were induced by polyethylene glycol, sodium chloride, and hydrogen peroxide, respectively. The expected increases in the abscisic acid levels and in the activities of antioxidant enzymes including catalase, ascorbate peroxidase, and glutathione reductase were found under each stress condition. The total thiamine compound content in the maize seedling leaves increased under each stress condition applied, with the strongest effects on these levels observed under the oxidative stress treatment. This increase was also found to be associated with changes in the relative distribution of free thiamine, thiamine monophosphate (TMP), and TDP. Surprisingly, the activity of the thiamine synthesizing enzyme, TMP synthase, responded poorly to abiotic stress, in contrast to the significant enhancement found for the activities of the TDP synthesizing enzyme, thiamine pyrophosphokinase, and a number of the TDP/TMP phosphatases. Finally, a moderate increase in the activity of transketolase, one of the major TDP-dependent enzymes, was detectable under conditions of salt and oxidative stress. These findings suggest a role of thiamine metabolism in the plant response to environmental stress.
TL;DR: P. euphratica plants subjected to saline conditions control ROS homeostasis through two pathways: (1) by maintaining cellular ionicHomeostasis and thereby limiting the NaCl-induced enhancement of ROS production under long-term saline conditions; and (2) by rapidly up-regulating antioxidant defenses to prevent oxidative damage.
Abstract: We investigated the effects of increasing soil NaCl concentration on intracellular compartmentalization of salt and on the activities of antioxidant enzymes (superoxide dismutase (SOD), ascorbic peroxidase (APX), catalase (CAT) and glutathione reductase (GR)) and their role in the regulation of reactive oxygen species (ROS; O(2)(-*) and H(2)O(2)) in leaves and xylem sap of salt-tolerant Populus euphratica Oliv. and salt-sensitive P. popularis cv. 35-44. Mesophyll cells of P. euphratica exhibited a high capacity for NaCl exclusion and compartmentalization of salt in vacuoles compared with P. popularis. In P. popularis, the salt treatment resulted in large accumulations of Na(+) and Cl(-) in leaves that induced significant increases in O(2)(-*) and H(2)O(2) production despite marked increases in the activities of antioxidant enzymes in leaves and xylem sap. Separation of the isoforms of leaf SOD, APX and CAT by polyacrylamide gel electrophoresis followed by in-gel activity staining revealed that the salt-induced activities of APX and CAT were the result of increases in activities of all the isoenzymes. Leaf injury and shedding of aged leaves occurred following the oxidative burst in P. popularis, indicating that the increased activities of antioxidant enzymes in P. popularis were insufficient to counter the harmful effects of ROS at high soil NaCl concentrations. Unlike P. popularis plants, P. euphratica plants did not exhibit an oxidative burst in response to the NaCl treatments, because of (1) a high salt exclusion capacity and effective compartmentalization of salt in vacuoles, and (2) up-regulation of antioxidant enzymatic activities after the onset of salt stress. We conclude that P. euphratica plants subjected to saline conditions control ROS homeostasis through two pathways: (1) by maintaining cellular ionic homeostasis and thereby limiting the NaCl-induced enhancement of ROS production under long-term saline conditions; and (2) by rapidly up-regulating antioxidant defenses to prevent oxidative damage.