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1.
The involvement of reactive oxygen species in chromate-induced genotoxicity has been postulated. Because intracellular antioxidants help in eliminating the reactive species of oxygen, we have investigated both the prooxidant and antioxidant status of human leukemic T-lymphocyte MOLT4 cells exposed to nontoxic levels of chromium(VI) in culture. The cells treated with 0 200 M potassium chromate in a salts/glucose medium for 2 h were found to contain significantly lower levels of both small molecular weight and macromolecular antioxidants. In particular, the levels of glutathione and ascorbate were found to decrease with increased doses of chromate exposure in a dose-dependent manner. As little as 10 M chromate was found to decrease these small molecular weight antioxidants significantly (p<0.01). The macromolecular antioxidants, such as glutathione peroxidase, catalase, glutathione reductase, glucose-6-phosphate dehydrogenase and superoxide dismutase were also significantly (p<0.01) decreased by exposing the cells to as little as 10 M chromate. Concomitantly there was a dose-dependent increase in intracellular H2O2 accumulation in cells exposed to chromium(VI). These results indicate that chromate-induced genotoxicity may be due, at least in part, to decreased levels of intracellular antioxidants in conjunction with an increased production of the reactive oxygen species. 相似文献
2.
Elizabeth A. L. Martins Lyria Mori H. C. Birnboim Rogerio Meneghini 《Molecular and cellular biochemistry》1992,117(2):181-189
We have investigated the antioxidant properties of V79 Chinese hamster cells rendered resistant to menadione by chronic exposure to increasing concentrations of this quinone. MD1, a clone of resistant cells, was compared to the parental M8 cells; the former showed increased activity of catalase (3 fold), glutathione peroxidase (1.6 fold) and DT-diaphorase (2.6 fold), as well as an increase in glutathione (3.2 fold). Although one of the products of menadione metabolism is superoxide anion, no changes in total superoxide dismutase activity was observed in MD1 cells. MD1 menadione resistant cells were also resistant to killing by hydrogen peroxide and contained tandem duplication of chromosome 6. A similar duplication of chromosome 6 was seen in several independently derived menadione resistant clones and therefore seems closed linked to the establishment of the resistance. Upon removal of menadione from the medium, some of these properties of MD1 cells, viz., resistance to menadione, elevated glutathione levels, and glutathione peroxidase activity, were lost and the cells resembled M8 cells. However, resistance to H2O2, elevated catalase activity and the duplicated chromosome remained stable for more than 40 cell passages in the absence of menadione. The increase in catalase activity was correlated with an increase in catalase mRNA content and a 50% amplification of catalase gene, as determined, respectively, by Northern and Southern blot analysis. The role of the chromosome 6 duplication in resistance to oxidative stress remains to be established. It is not responsible directly for elevated catalase levels since the catalase gene is on chromosome 3.Abbreviations SDS
Sodium Dodecyl Sulphate
- SOD
Superoxide Dismutase
- PBS
Phosphate Buffered Saline (8.1 mM Na2HPO4, 1.47 mM KH2PO4, 2.68 mM KCl, 137 mM NaCl)
- CDTA
N,N,N,N-tetracetic-trans-1,2-diaminocyclohexane acid
- MOPS
Sulphonic-3-(N-morpholine)-propane acid
- SSC
150 mM Nacl, 15 mM sodium-citrate, pH 6.8 相似文献
3.
Utilization of highly enriched preparations of steroidogenic Leydig cells have proven invaluable for studying the direct effects of various hormones and agents on Leydig cell functionin vitro. However, recent work indicates that isolated Leydig cells are often subjected to oxygen (O2) toxicity when cultured at ambient (19%) oxygen concentrations. Because intracellular antioxidants play an important role in protecting cells against oxygen toxicity, we have investigated the intracellular antioxidant defense system of isolated Leydig cells. The cellular levels of several antioxidants including catalase, glucose-6-phosphate dehydrogenase (G-6-PDH), superoxide dismutase (SOD) of the Cu/Zn & Mn variety, glutathione peroxidase, glutathione reductase and total glutathione were quantitated using enriched populations of Leydig cells isolated from adult male guinea pig testes. Compared to whole testicular homogenates, Leydig cells contained significantly (P<0.01) less G-6-PDH, total SOD, glutathione reductase and total glutathione, but significantly (P<0.001) more glutathione peroxidase. Compared to hepatic values previously reported in the guinea pig, Leydig cells contain nearly 400 times less catalase, about 14 times less glutathione peroxidase and almost 11 times less glutathione reductase. Since G-6-PDH and glutathione reductase are both necessary to regenerate reduced gluthathione (GSH) which couples with glutathione peroxidase to breakdown hydrogen peroxide (H2O2) under normal conditions, it is plausible that the oxygen toxicity observed in isolated Leydig cells is due to the intracellular accumulation of H2O2. Using the dichlorofluorescin diacetate (DCF-DA) assay, we found that Leydig cells incubated in the presence of 19% O2 produced significantly (P<0.001) higher levels of H2O2 with time in culture compared to Leydig cells maintained at 3% O2. These results support the hypothesis that the increased susceptibility of isolated Leydig cells to oxygen toxicity may be due, in part, to decreased amounts of certain antioxidant defenses and an increased production of the reactive oxygen species H2O2. 相似文献
4.
The transition metal elements like copper act as double-edged sword for living cells. Cu, a redox active metal, is essential for various biological processes, but at higher concentrations it leads to toxicity by inducing production of reactive oxygen species (ROS). Thus, the objective of the present study was to investigate the effects of exogenously applied castasterone on oxidative stress markers and redox homeostasis managers in Brassica juncea plants subject to copper stress for 30 days. Copper-exposed plants showed accumulation of free radicals (H2O2 and superoxide anion) and lipid peroxidation. However, the exogenous treatment of seeds via the seed soaking method with different concentrations of castasterone reduced H2O2 production, superoxide anion radical content, and lipid peroxidation, thus indicating improved detoxification of ROS. Enzyme activity was increased by 19.19% for guaiacol peroxidase, 16.20% for superoxide dismutase, 35.74% for glutathione peroxidase, 27.58% for dehydroascorbate reductase, and 42.75% for ascorbate peroxidase, with castasterone pre-soaking under copper stress. The levels of non-enzymatic antioxidants were also increased with castasterone pre-treatment under copper stress. It may be concluded that castasterone treatment enhanced redox homeostasis managers in addition to increased levels of osmoprotectants. 相似文献
5.
《Free radical research》2013,47(5-6):323-334
The protection of human diploid fibroblasts against high oxygen tension was investigated using various combinations of the three major antioxidant enzymes: superoxide dismutase, catalase and gluthathione peroxidase. α-Tocopherol, a well-known hydrophobic antioxidant, was also tested in combination with the different enzymes. Microinjection of solutions containing different combinations of the three enzymes was compared with the injection of each single enzyme. We observed that the protections given by catalase or superoxide dismutase on the one hand, and by glutathione peroxidase on the other hand, were additive. Surprisingly, the combinations of catalase and superoxide dismutase were less effective than catalase alone and was even toxic at low SOD concentrations. Addition of α-tocopherol following the injection of any of the three enzymes was highly beneficial, but the strongest synergistic effect was obtained with glutathione peroxidase. These results stress the importance of membrane protection by α-tocopherol and indirectly by glutathione peroxidase. They also showed that any injection leading to the decrease in the O2?. or H2 O 2 concentration combined with one of these two protectors is very beneficial for the cells probably by decreasing the OH concentration. This is also proven by the very good protective effect obtained with desferrioxamine. 相似文献
6.
Reactive oxygen species and antioxidant machinery in abiotic stress tolerance in crop plants 总被引:24,自引:0,他引:24
Various abiotic stresses lead to the overproduction of reactive oxygen species (ROS) in plants which are highly reactive and toxic and cause damage to proteins, lipids, carbohydrates and DNA which ultimately results in oxidative stress. The ROS comprises both free radical (O2?, superoxide radicals; OH, hydroxyl radical; HO2, perhydroxy radical and RO, alkoxy radicals) and non-radical (molecular) forms (H2O2, hydrogen peroxide and 1O2, singlet oxygen). In chloroplasts, photosystem I and II (PSI and PSII) are the major sites for the production of 1O2 and O2?. In mitochondria, complex I, ubiquinone and complex III of electron transport chain (ETC) are the major sites for the generation of O2?. The antioxidant defense machinery protects plants against oxidative stress damages. Plants possess very efficient enzymatic (superoxide dismutase, SOD; catalase, CAT; ascorbate peroxidase, APX; glutathione reductase, GR; monodehydroascorbate reductase, MDHAR; dehydroascorbate reductase, DHAR; glutathione peroxidase, GPX; guaicol peroxidase, GOPX and glutathione-S- transferase, GST) and non-enzymatic (ascorbic acid, ASH; glutathione, GSH; phenolic compounds, alkaloids, non-protein amino acids and α-tocopherols) antioxidant defense systems which work in concert to control the cascades of uncontrolled oxidation and protect plant cells from oxidative damage by scavenging of ROS. ROS also influence the expression of a number of genes and therefore control the many processes like growth, cell cycle, programmed cell death (PCD), abiotic stress responses, pathogen defense, systemic signaling and development. In this review, we describe the biochemistry of ROS and their production sites, and ROS scavenging antioxidant defense machinery. 相似文献
7.
The 24 h effect of low (20°C) and high (43°C) temperature on the antioxidant enzyme activities and lipid peroxidation was
investigated in intact cells of the cyanobacteriumSynechocystis PCC 6803 grown at 36°C. At low temperature treated cells, the superoxide dismutase, catalase and glutathione peroxidase activities
were significantly higher and the protein content lower than in high temperature treated cells. The increase of hydroxyl free
radical level and malonyldialdehyde formation, when algal cells were exposed to low temperature, were due to the stimulated
production of superoxide radicals O2
− and hydrogen peroxide (H2O2). 相似文献
8.
Kim H Son HJ Ha SC Kim EA Kim TU Choi SY Ahn JY Cho SW 《Cellular and molecular neurobiology》2011,31(7):979-984
Oxidative stress, glutamate excitotoxicity, and inflammation are the important pathological mechanisms in neurodegenerative
diseases. Recently, we reported that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride protects rat glial cells against
glutamate-induced excitotoxicity. In this study, we report the effects of 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride
on primary cultured cortical astrocytes after exposure to hydrogen peroxide (H2O2). Pretreatment of cells with 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride prior to H2O2 exposure attenuated the H2O2-induced reductions in cell survival and superoxide dismutase, catalase, glutathione, and glutathione peroxidase activities.
It also reduced H2O2-induced increases in reactive oxygen species levels, malondialdehyde content, and production of nitric oxide. These effects
were all concentration-dependent. Our results suggest that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride protects
against oxidative stress. 相似文献
9.
I. Mavelli M.R. Ciriolo G. Rotilio P. De Sole M. Castorino A. Stabile 《Biochemical and biophysical research communications》1982,106(2):286-290
Superoxide dismutase, glutathione peroxidase and catalase were assayed in the erythrocytes of three patients of Fanconi's anemia. Superoxide dismutase was found to be significantly decreased, as previously reported. The enzymes metabolizing H2O2 are normal (glutathione peroxidase in the higher limits of the normal value). The abnormal erythrocytes were found to be as resistant (perhaps more resistant) as normal red blood cells to oxidative hemolysis induced by drugs. Malonyl dialdehyde production was found to be comparable to that of normal erythrocytes. It is concluded that a significant (30–40%) deficiency of superoxide dismutase, when associated to normal values of H2O2-removing enzymes, does not affect the antioxidative defense capability of erythrocytes, even in conditions of augmented oxidative injury. 相似文献
10.
1. Growth of Chlorella sorokiniana in the presence of 7.5 mM sulfite, which halved the growth rate while doubling the superoxide dismutase (SOD; EC 1.15.1.1) content per cell, rendered the cells resistant to the toxic effects of 30 M paraquat. 2. While increasing total SOD content, sulfite increased the relative amount of the H2O2-resistant manganese-containing SOD. 3. It appears that O2
– may be involved in mediating the toxicity of SO2 in this green alga.Abbreviations SOD
superoxide, dismutase
- FeSOD
ironcontaining superoxide dismutase
- MnSOD
manganese-containing superoxide dismutase 相似文献
11.
Summary The in vivo induction of H2O2 production was tested on tobacco cell suspension cultures (Nicotiana tabacum cv. Bright Yellow-2). The measurement of H2O2 was based on the oxidation of 3,5-dichloro-2-hydroxybenzensulfonic acid by endogenous peroxidases and spectrophotometric detection after reaction with 4-aminoanti-pyrine. The phosphatase inhibitor cantharidin induced a transient increase in H2O2 synthesis. The timing of the H2O2 production, the level of induction by cantharidin and the background H2O2 production were dependent on the tobacco cell concentration used. A concentration curve of cantharidin revealed saturating kinetics for the H2O2 detection (E50=46 to 70 M, Emax=101 to 128 mol/h·g fresh weight). An inhibitor study with the tobacco BY-2 cells showed high inhibitions of the H2O2 induction with the flavin analogues diphenylene iodonium (I50=1.26M) and acridine orange and with membrane-permeative thiol reagents (N-ethyl maleimide, N-pyrene maleimide, iodoacetate); whereas the nonpermeative thiol reagentp-chloromercuribenzoic acid was ineffective. Therefore, the induction of H2O2 production with phosphatase inhibitors (cantharidin) showed comparable properties to the elicitor-induced oxidative-burst response in other plant cells.Abbreviations AcOr
acridine orange
- AOS
active-oxygen species
- BY-2
Bright Yellow-2
- pCMBS
p-chloromercuribenzoic acid
- DHBS
3,5-dichloro-2-hydroxybenzenesulfonic acid
- DMSO
dimethylsulfoxide
- DPI
diphenylene iodonium
- EtOH
ethanol
- H2O2
hydrogen peroxide
- HRP
horseradish peroxidase
- MS
Murashige and Skoog
- NEM
N-ethyl maleimide
- NPM
N-pyrene maleimide
- O
2
–
superoxide
- SOD
superoxide dismutase 相似文献
12.
This article encompasses the results on the effects of 24-epibrassinolide (EBR) on the changes in reactive oxygen species (ROS) and activities of antioxidative enzymes in radish (Raphanus sativus L.) seedlings subjected to zinc (Zn) stress. Zn toxicity resulted in significant enhancement in the level of membrane lipid peroxidation, protein oxidation, contents of hydrogen peroxide (H2O2) and hydroxyl radical (·OH), the production rate of superoxide radicals (O 2 ·? ) and the activities of lipoxygenase and NADPH oxidase in radish seedlings indicating the induction of oxidative stress. However, Zn-mediated enhancement in indices of oxidative stress was considerably decreased by EBR treatment. EBR application enhanced the activities of catalase, superoxide dismutase, guaiacol peroxidase, glutathione peroxidase, and peroxidase in radish seedlings under Zn stress. EBR treatment reduced the activity of ascorbic acid oxidase in Zn stressed seedlings. Further, EBR application also enhanced the free proline and phenol levels under Zn stress. From the results obtained in this study, it can be inferred that EBR application alleviated oxidative damage caused by over production of ROS through the up regulation of antioxidative capacity in Zn stressed radish seedlings. 相似文献
13.
14.
C. Jeulin J. C. Soufir P. Weber D. Laval-Martin R. Calvayrac 《Molecular reproduction and development》1989,24(2):185-196
Catalase activity was determined in human semen by measuring the oxygen burst with a Clark electrode, after H2O2 addition. Significant catalase activities (mean ± SD) were found in migrated, motile spermatozoa (44 ± 17 nmoles O2/min/108 cells) and in seminal plasma of normozoospermic men (129 ± 59 nmoles O2/min/ml). It has been demonstrated that seminal catalase originated from prostate; however, its activity was not correlated with the usual prostatic markers (such as citric acid and zinc). Our data suggest a multiglandular function secreted by this organ. The catalase activities measured in seminal samples from asthenozo-ospermic, infertile men were found lower than those from normozoospermic subjects. The understanding of the relative contribution of the different enzyme systems against O2 toxicity (superoxide dismutase, catalase, glutathione peroxidase) seem to be a priority area of research to understand disturbances of sperm function. 相似文献
15.
A methyl viologen (MV)* mediated Mehler reaction was studied using Type C and D chloroplasts (thylakoids) from spinach. The extent of photooxidative reactions were measured as (a) rate of ethylene formation from methional oxidation indicating the production of oxygen radicals, and (b) rate of malondialdehyde (MDA) formation as a measure of lipid peroxidation. Without added ascorbate, 1 M FerricEDTA increased ethylene formation by greater than 4-fold, but had no effect on MDA production. Ascorbate (1 mM) produced a tripling of ethylene while it reduced MDA formation in the presence of iron. Radical scavengers diethyldithiocarbamate (DDTC), formate, 1,4-diazabicyclo (2.2.2octane) (DABCO), inhibited ethylene formation. Using 0,4 M mannitol to scavenge hydroxyl radicals, the rates of ethylene formation were reduced 40 to 60% with or without 1 M Fe(III) EDTA. The strong oxidant(s) not scavenged by mannitol are hypothesized to be either alkoxyl radicals from lipid peroxidation, or site specific formation of hydroxyl radicals in a lipophillic environment not exposed to mannitol. Singlet oxygen does not appear to be a significant factor in this system. Catalase strongly inhibited both ethylene and MDA synthesis under all conditions; 1 mM ascorbate did not reverse this inhibition. However, the strong superoxide dismutase (SOD) inhibition of ethylene and MDA formation was completely reversed by 1 mM ascorbate. This suggests that superoxide was functioning as an iron reducing agent and that in its absence, ascorbate was similarly promoting oxidations. Therefore, these oxidative processes were dependent on the presence of H2O2 and a reducing agent, suggesting the involvement of a Fenton-type reaction.Abbreviation DABCO
1,4-diazabicyclo(2.2.2.octane)
- DCMU
3-(3,4 Dichlorophenyl). 1,1-dimethyl urea
- DDTC
diethyldithiocarbamate
- EDTA
ethylenediamine-tetraacetic acid
- MDA
malondialdehyde
- MV
methyl viologen
- SOD
superoxide dismutase
- TBA
thiobarbituric acid
- TCA
trichloroacetic acid
Scientific contribution number 1315 from the New Hampshire Agriculture Experiment Station. 相似文献
16.
Vitrification of shoots of Prunus avium L. L. was induced and expressed in a four week in vitro multiplication cycle simply by replacing agar by gelrite. The first vitrification symptoms were visible from the 7th day on. Enzymatic antioxidants were compared weekly in crude extract of normal (on agar) and vitrifying (on gelrite) shoots. The activity of superoxide dismutase was higher in vitrifying shoots. The other enzymes (gaîacol-peroxidase, catalase, ascorbate peroxidase, mono- and dehydro-ascorbate reductases, glutathione reductase) had lower activities. Increased superoxide dismutase activity might mean hydrogen peroxide accumulation and decreased activities of the other enzymes, deficiency in its detoxification. The question therefore is raised whether the hyperhydric morphological abnormalities result from the accumulation of toxic oxygen forms. Vitrification is often considered as a morphological response to several stresses. Contrary to most plants which adapt themselves to stresses by increasing all the above defence enzymes, in vitro shoots under vitrifying conditions appear unable to react in a similar manner.Abbreviations Apx
ascorbate peroxidase
- Gpx
gaîacol peroxidase
- CAT
catalase
- H2O2
hydrogen peroxide
- SOD
superoxide dismutase
- MDHAR
monodehydroascorbate reductase
- DHAR
dehydroascorbate reductase
- GR
glutathione reductase
- MS
Murashige and Skoog (1962)
- IBA
indolebutyric acid
- BAP
benzyladenine
- GA3
gibberellic acid 相似文献
17.
Ye J Ding M Leonard SS Robinson VA Millecchia L Zhang X Castranova V Vallyathan V Shi X 《Molecular and cellular biochemistry》1999,202(1-2):9-17
Apoptosis is a physiological mechanism for the control of DNA integrity in mammalian cells. Vanadium induces both DNA damage and apoptosis. It is suggested that vanadium-induced apoptosis serves to eliminate DNA-damaged cells. This study is designed to clarify a role of reactive oxygen species in the mechanism of apoptosis induced by vanadium. We established apoptosis model with murine epidermal JB6 P+ cells in the response to vanadium stimulation. Apoptosis was detected by a cell death ELISA assay and morphological analysis. The result shows that apoptosis induced by vanadate is dose-dependent, reaching its saturation level at a concentration of 100 M vanadate. Vanadyl (IV) can also induce apoptosis albeit with lesser potency. A role of reactive oxygen species was analyzed by multiple reagents including specific scavengers of different reactive oxygen species. The result shows that vanadate-induced apoptosis is enhanced by NADPH, superoxide dismutase and sodium formate, but was inhibited by catalase and deferoxamine. Cells exposed to vanadium consume more molecular oxygen and at the same time, produce more H2O2 as measured by the change in fluorescence of scopoletin in the presence of horseradish peroxidase. This change in oxygen consumption and H2O2 production is enhanced by NADPH. Taken together, these results show that vanadate induces apoptosis in epidermal cells and H2O2 induced by vanadate plays a major role in this process. 相似文献
18.
Responses of Camellia sinensis to Drought and Rehydration 总被引:2,自引:1,他引:1
The effects of drought and rehydration on tea seedlings were significant. After five days of drought imposition the contents of chlorophylls, carotenoids, ascorbate and glutathione, and activities of guaiacol peroxidase and glutathione reductase decreased. Simultaneously, contents of proline, H2O2 and superoxide anion, lipid peroxidation and activities of catalase and superoxide dismutase increased. These parameters recovered to different degrees during subsequent rehydration. 相似文献
19.
A. K. Glyan’ko G. P. Akimova L. E. Makarova M. G. Sokolova G. G. Vasil’eva 《Applied Biochemistry and Microbiology》2007,43(5):516-522
A possible physiological mechanism of legume-Rhizobium symbiosis, consisting in regulation of the intensity of oxidative processes by the macrosymbiont in response to infection with Rhizobium, was analyzed using our own and published data. The results used in the analysis included data on the content of reactive oxygen species (O 2 ·? and H2O2), activity of antioxidant enzymes (superoxide dismutase, catalase, and peroxidase), and intensity of lipid peroxidation proceeding with the involvement of lipophilic phenolic compounds of the microsymbiont. 相似文献
20.
E. A. Kosenko L. A. Tikhonova A. S. Pogosyan Yu. G. Kaminsky 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2012,6(3):273-277
Age of patients and oxidative stress in brain cells may contribute to pathogenesis of Alzheimer’s disease (AD). Erythrocytes (red blood cells, RBC) are considered as passive “reporter cells” for the oxidative status of the whole body and remain poorly investigated in AD. The aim of this study was to assess whether the antioxidant status of RBC changes in aging and AD. Blood was taken from AD and non-Alzheimer’s dementia patients, aged-matched and younger controls. The antioxidant status of RBC was evaluated in each person participated in the study by measuring levels of H2O2, organic hydroperoxides, glutathione (GSH) and glutathione disulfide (GSSG), activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase, and glucose-6-phosphate dehydrogenase. In both aging and dementia, oxidative stress in RBC was shown to increase as evidenced by elevated concentrations of H2O2, organic hydroperoxides, decreased GSH/GSSG ratio, and decreased glutathione S-transferase activity. Decreased glutathione peroxidase activity in RBC may be considered as a new peripheral marker for Alzheimer’s disease while changes of other parameters of oxidative stress reflect age-related events. 相似文献