共查询到20条相似文献,搜索用时 15 毫秒
1.
N. I. Shevyakova B. Ts. Eshinimaeva Vl. V. Kuznetsov 《Russian Journal of Plant Physiology》2011,58(5):768-775
In plants of the facultative halophyte Mesembryanthemum crystallinum L. cultivated under climate-controlled conditions, expression of one of ferritin genes, McFer, the ortholog of arabidopsis AtFer1 gene was studied for the first time. The level of this gene expression occurring in response to oxidative stress and changes
in the iron status was similar to that of AtFer1 gene. A dependence of McFer gene expression and ferritin content on the regime of plant supplying with Fe-EDTA on the background of medium salinity (300
mM NaCl), oxidative stress modeling by leaf treatment with paraquat (PQ, 100 μM), or in the presence of antioxidant spermidine
(Spd, 1 mM) was analyzed. The level of gene expression was assessed by RT-PCR, whereas the content of ferritin by Western
blotting, using the primary polyclonal antibody against pea ferritin. An enhanced production of superoxide radical and hydrogen
peroxide at leaf treatment with PQ activated gene expression and ferritin content, whereas ROS scavenging with the antioxidant
Spd suppressed gene expression. It is concluded that ferritin deposits in the halophyte M. crystallinum, which we have observed earlier in the chloroplasts of the mesophyll and parenchyma of the vascular system, fulfill not only
storage but also protective role by binding the excessive Fe2+, a catalyzer of OH·− production. 相似文献
2.
Khadiga G. Adham Ahlam A. Alkhalifa Manal H. Farhood Nadia A. Aleisa Maha H. Daghestani 《Biologia》2014,69(6):817-824
Iron saccharate complex ISC is an iron supplement used to optimize erythropoiesis in cases of iron deficiencies. Because of the lack of major mechanisms of iron excretion, excess iron unbound to protective molecules is believed to be involved in catalyzing the generation of reactive oxygen species and induction of oxidative stress. This study employed ISC for the purpose of inducing iron overload and hence investigating the consequent iron toxicity, lipid peroxidation and antioxidant extent in a murine species. Male Wistar rats were given iron as intraperitoneal injections of ISC in subacute (0.2 mg Fe kg?1 for 2 weeks) and subchronic (0.1 mg Fe kg?1 for 4 weeks) doses. In iron-overloaded rats, enhanced hepatic iron accumulation (P > 0.001) attended by increased serum concentrations of malondialdehyde (MDA) (P > 0.001) and activities of antioxidant enzymes (superoxide dismutase SOD, catalase CAT and glutathione peroxidase GPx) (P > 0.001) was pointed out. The demonstrated antioxidant boost is attributed to a sense of equilibrium prompted by the potential of iron-induced oxidative stress to modify antioxidant defense capacity and to modulate susceptibility to oxidative stress. Rats seemed to constantly suffer from oxidative stress based on the consistent rise in MDA that was not overwhelmed by the elevated antioxidant input. The current findings are of informative value in drawing attention to the health hazards of applying higher doses of the commercially used iron supplement ISC. Data are virtually significant in elucidating the higher magnitude of subchronic than subacute iron overload in initiating oxidative stress and antioxidant defense. Both pathways proceeded in a time-dependent rather than dose-dependent manner. 相似文献
3.
4.
Binay Bhusan Panda Srigopal Sharma Pravat Kumar Mohapatra Avijit Das 《Journal of plant biochemistry and biotechnology.》2016,25(4):382-391
Iron homeostasis was studied in two tropical indica rice cultivars viz. Sharbati (high Fe) and Lalat (low Fe) having contrasting grain Fe concentration. Plants were hydroponically grown with 5 concentrations of Fe (0.05, 2, 5, 15, 50 mg L?1) till maturity. The effect of incremental Fe treatment on the plant was followed by analyzing accumulation of ferritin protein, activities of aconitase enzyme, enzymes of anti-oxidative defense and accumulation of hydrogen peroxide and ascorbic acid. Plant growth was adversely affected beyond 15 mg L?1 of Fe supplementation and effects of Fe stress (both deficiency and excess) were more apparent on the high Fe containing cultivar Sharbati than the low Fe containing Lalat. Level of ferritin protein and aconitase activity increased up to 5 mg L?1 of Fe concentration. Lalat continued to synthesize ferritin protein at much higher Fe level than Sharbati and the cultivar also had higher activities of peroxidase, superoxide dismutase and glutathione reductase. It was concluded that the tolerance of Lalat to Fe stress was because of its higher intrinsic ability to scavenge free radicals of oxidative stress for possessing higher activity of antioxidative enzymes. This, together with its capacity to sequester the excess Fe in ferritin protein over a wider range of Fe concentrations made it more tolerant to Fe stress. 相似文献
5.
In this study, the expression patterns of four ferritin genes (PpFer1, PpFer2, PpFer3, and PpFer4) in pear were investigated using quantitative real-time PCR. Analysis of tissue-specific expression revealed higher expression
level of these genes in leaves than in other tested tissues. These ferritin genes were differentially expressed in response
to various abiotic stresses and hormones treatments. The expression of ferritin wasn’t affected by Fe(III)-citrate treatment.
Abscisic acid significantly enhanced the expression of all four ferritin genes, especially PpFer2, followed by N-benzylyminopurine, gibberellic acid, and indole-3-acetic acid. The expression peaks of PpFer1 and PpFer3 in leaves appeared at 6, 6, and 12 h, respectively, after pear plant was exposed to oxidative stress (5 mM H2O2), salt stress (200 mM NaCl), and heat stress (40°C). A significant increase in PpFer4 expression was detected at 6 h after salt stress or heat stress. The expression of ferritin genes was not altered by cold
stress. These results suggested that ferritin genes might be functionally important in acclimation of pear to salt and oxidative
stresses. Hormone treatments had no significant effect on expression of ferritin genes compared to abiotic stresses. This
showed accumulation of ferritin genes could be operated by different transduction pathways under abiotic stresses and hormones
treatments. 相似文献
6.
Oxidative stress is detrimental to sperm function and a significant factor in the etiology of male infertility. Present study
evaluates the effect of ter butyl hydroperoxide (TBHP)-induced oxidative stress on the spermatogenic process and cell number
in the seminiferous tubules. Intraperitoneal injection of TBHP (84 μmol TBHP/100 g body weight) for 2 weeks to male Balb/c
mice resulted in enhanced lipid peroxidation (P < 0.0001) decrease in reduced glutathione (P < 0.0001) and increase in the oxidized glutathione levels (P = 0.007) in the testis. Status of spermatogenesis after the treatment was assessed by the quantitative methods of germ cell
evaluation in the seminiferous tubules. A significant decrease in the number of young spermatids (P = 0.0003) and pachytene cells (P = 0.022) was observed. A marked reduction was also seen in the mature spermatid number (P < 0.0001). An increase in testicular mRNA levels of redox-regulated cjun (P = 0.008) and cfos (P = 0.0006) subunits of activator protein 1 (AP1) was observed after TBHP treatment. Evaluation of AP1 regulated antioxidant
enzymes in the testis revealed an increase in γ-glutamyl cysteine synthetase (GCS) mRNA expression (P = 0.001). These results suggest a potential role of AP1 in oxidative stress-mediated meiotic and post meiotic changes in
the spermatogenic process and regulation of cell number in male reproductive system. 相似文献
7.
Significant changes were observed in the antioxidant systems in the leaves of black gram (Vigna mungo L., var. DPU-88-31) grown under deficient and excess supply of Zn. Plant grown with Zn supply ranging from 0.01 to 10.0 μM
under glasshouse conditions showed optimal growth and biomass yield at 1.0 μM Zn supply. Deficient (0.001 and 0.01 μM) as
well as excess (2.0 and 10.0 μM) supply of Zn decreased the concentrations of chlorophyll, carotenoids, and nonprotein thiols
and increased that of ascorbate. The activity of superoxide dismutase and carbonic anhydrase was decreased at deficient levels
and increased with increase in Zn supply up to 10 μM. At both stages of growth, the activities of antioxidant enzymes, such
as catalase and ascorbate peroxidase, were decreased, whereas the activities of glutathione reductase and peroxidase were
increased at both deficient and excess supply of Zn. An accumulation of hydrogen peroxide and thiobarbituric acid-reactive
substances was observed in Zn-stressed leaves, indicating oxidative damage. Different responses to deficient and excess supply
of Zn were observed in the production of oxidative damage. 相似文献
8.
Iron Enhances Aluminum-induced Leaf Necrosis and Plant Growth Inhibition in Eucalyptus camaldulensis
The combined effects of excess Fe and Al on Eucalyptus camaldulensis Dehnh. were studied by investigating time course and visible symptoms of leaf necrosis, plant biomass, the status of some
antioxidants and pigments and nutrient concentrations. Seedlings were grown hydroponically in nutrient solutions containing
0 or 500 μM AlCl3, each with a FeSO4 range of 1, 12 and 120 μM at pH 4.2. Leaf necrosis and plant growth inhibition were induced by Al and enhanced by the increase in Fe concentration.
The process from the first appearance of necrotic spots to leaf death (shedding) of a leaf proceeded from a few days to about
20 days after the leaf had fully expanded. Either 120 μM Fe without Al or Al reduced plant growth to a similar extent but 120 μM Fe without Al did not cause leaf necrosis. In leaves, excess Fe (12 and 120 μM) without Al reduced concentration of ASC and GSH, while concentration of Fe, DHA and GSSG and DHA:ASC and GSSG:GSH ratios
tended to increase with the increase in Fe concentration in treatment solution with or without Al. At 1 μM Fe, Al increased concentration of DHA and DHA:ASC and GSSG:GSH ratios. Catalase activity in leaves reduced with the increase
in leaf Al concentration. At 1 μM Fe, Al greatly reduced concentrations of Fe and chlorophylls in leaves but increase two times Fe concentration in stems.
These suggest that the enhancement effects of Fe on Al-induced leaf necrosis and plant growth inhibition can be discussed
in context of the excess Fe itself weakens antioxidant capability of ASC–GSH cycle in leaves and greatly reduces plant growth;
and the increase in Fe accumulation in stems is involved in Al-induced leaf chlorosis. 相似文献
9.
Iron is essential to plants. However, when free and in excess, iron can catalyze the formation of oxygen free radicals. Ferritin, a protein capable of storing up to 4500 atoms of iron, can act as an iron buffer inside plant cells. Using a strategy based in amplicon size difference, we were able to analyze the expression profile of the two rice ferritin genes (OsFER1 and OsFER2). Both genes are expressed, although with different regulation and organ distribution. Exposure to copper, Paraquat, SNP and excess iron led to accumulation of ferritin mRNA, remarkably of OsFER2. The iron-induced expression was abolished by treatment with GSH, indicating that the induction observed is dependent of an oxidative step. OsFER2 mRNA levels in rice flag leaves and panicles at different reproductive stages were higher than OsFER1 mRNA levels. No ferritin mRNA was detected in rice seeds. However, imbibition under light led to ferritin expression, which was abolished when seeds were kept in the dark, suggesting a light-regulated induction. Ferritin mRNA accumulation was seen in the dark only when seeds were germinated in the presence of externally supplied iron. We suggest that the primary role of rice ferritins is related to defense against iron-mediated oxidative stress. 相似文献
10.
Ann Van Campenhout Christel Van Campenhout Albert Lagrou Begoña Manuel-y-Keenoy 《Biometals》2008,21(2):159-170
Background: Administration of intravenous iron preparations in haemodialysis patients may lead to the appearance of non-transferrin
bound iron which can catalyse oxidative damage. We investigated this hypothesis by monitoring the oxidative stress of haemodialysis
patients and the impact of iron and diabetes mellitus herein. Materials and methods: Baseline values of serum iron and related proteins, transferrin glycation, non-transferrin bound iron, antioxidant capacity
and lipid peroxidation (malondialdehyde) of 11 haemodialysis patients (six non-diabetic and five type 2 diabetes) were compared
to those of non-haemodialysis control subjects (non-diabetic and type 2 diabetes). Changes in these parameters were monitored
during haemodialysis before and after iron administration. Results: Baseline values of malondialdehyde correlated with ferritin concentration (r = 0.664, P = 0.036) and were elevated to the same extent in non-diabetic and diabetic haemodialysis patients (median of 1.09 compared
to 0.60 μmol/l in control persons, P < 0.02). After iron infusion, transferrin saturation increased more markedly in non-diabetic subjects from 28% to 185% vs.
from 33% to 101% in diabetic patients (P = 0.008). This increase was accompanied by the appearance of non-transferrin bound iron (5.91 ± 1.33 μmol/l), a loss in plasma
iron-binding antioxidant capacity and a further increase in malondialdehyde which was more pronounced in diabetic patients
(from 0.93 ± 0.30 μmol/l to 2.21 ± 0.69 μmol/l vs. from 1.21 ± 0.42 μmol/l to 1.86 ± 0.56 μmol/l in the non-diabetic subjects,
P = 0.046). Conclusions: In haemodialysis patients, higher lipid peroxidation is determined by higher body iron stores. The increase induced by iron
infusion is accompanied by a loss in iron-binding antioxidant capacity and is more pronounced in diabetes mellitus. 相似文献
11.
Copper-induced changes in the growth, oxidative metabolism, and saponin production in suspension culture roots of Panax ginseng in bioreactors 总被引:3,自引:0,他引:3
Roots of Panax ginseng exposed to various concentrations of Cu (0.0, 5, 10.0, 25.0, and 50.0 μM) accumulated high amounts of Cu in a concentration-dependent and duration-dependent manner. Roots treated with 50 μM Cu resulted in 52% and 89% growth inhibition after 20 and 40 days, respectively. Saponin synthesis was stimulated at a Cu concentration between 5 and 25 μM but decreased at 50 μM Cu. Malondialdehyde content (MDA), lipoxygenase activity (LOX), superoxide ion (O2
•−) accumulation, and H2O2 content at 5 and 10 μM Cu-treated roots were not increased but strongly increased at 50 μM Cu resulting in the oxidation of ascorbate (ASC) and glutathione (GSH) to dehydroascorbate (DHA) and glutathione disulfide (GSSG), respectively indicating a clear oxidative stress. Seven well-resolved bands of superoxide dismutase (SOD) were detected in the gel and an increase in SOD activity seemed to be mainly due to the induction of Fe-SOD 3. Five to 10 μM Cu slightly induced activity of ascorbate peroxidase (APX) and dehydroascorbate reductase (DHAR), guaiacol peroxidase (G-POD) but inhibited monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR) enzyme activities. No changes in catalase (CAT) activity and in activity gel were found up to 25 μM Cu, but both G-POD and CAT activities were inhibited at 50 μM Cu. Glutathione metabolism enzymes such as γ-glutamylcysteine synthetase (γ-GCS), glutathione-S-transferase (GST), and glutathione peroxidase activities (GPx) were activated at 5 and 10 μM Cu but were strongly inhibited at 50 μM Cu due to the Cu accumulation in root tissues. The strong depletion of GSH at 50 μM Cu was associated to the strong induction of γ-glutamyltranspeptidase (γ-GGT) activity. These results indicate that plant could grow under Cu stress (5–25 μM) by modulating the antioxidant defense mechanism for combating Cu induced oxidative stress. 相似文献
12.
In view of the known involvement of oxidative stress and calcineurin (Ca2+-calmodulin dependent protein phosphatase) in β-Adrenergic stimulated events, we examined the influence of eugenol (an antioxidant
generally regarded as safe by the Food and Agricultural Organization of the United Nations) on isoproterenol-induced apoptosis
in neonatal cardiomyocytes. In comparison to unstimulated controls, cardiomyocytes stimulated with 50 μM isoproterenol for
48 h demonstrated (a) increased intracellular Ca2+ levels (b) oxidative stress involving enhanced reactive oxygen species, decreased GSH/GSSG ratio, enhanced lipid peroxidation,
increased activities of superoxide dismutase and glutathione peroxidase (c) apoptosis, evidenced by increased number of annexin
V/TUNEL positive cells, enhanced membrane fluidity, decreased mitochondrial membrane potential, increased activities of caspase
3 and 9 along with (d) increased calcineurin activity. Pre-incubation of cardiomyocytes with 100 μM eugenol for 1 h, followed
by isoproterenol treatment for 48 h, led to reversal of enhanced intracellular Ca2+ levels, oxidative stress, calcineurin activation and apoptosis caused by isoproterenol. In addition, similar treatment of
cardiomyocytes with 10 nM FK506, a calcineurin inhibitor, could also attenuate isoproterenol-induced apoptosis. These results
indicate the beneficial effects of eugenol in preventing cardiomyocyte apoptosis. 相似文献
13.
Aluminium toxicity has been recognized as a primary growth-limiting factor in acid soil, resulting in a decrease in plant
growth and production. In this experiment we have studied the induction of oxidative stress and changes in antioxidant gene
expression in pea (var. ALASKA) under aluminium (Al) stress. We have found that Al treatment affected the growth of pea plant
and induced oxidative stress with a change in antioxidant gene expression profile. While the expression of glutathione-s-transferase
(GST) and catalase (CAT) was more in root, cytosolic Ascorbate peroxidase (cAPX) expression increased in shoot under aluminium stress. Copper- Zinc Superoxide dismutase (Cu-Zn SOD) gene expression was
higher after 24 h but decreased after 48 h along with elevated expression of manganese superoxide dismutase (MnSOD) and iron-superoxide dismutase (FeSOD) at higher aluminium contentrations after 24 and 48 h. Aluminium stress elevated hydrogen peroxide (H2O2) level and affected the growth. The proline content did not change significantly, whereas glutathione content increased with
a decreased ascorbate content under Al stress. The present study indicates that aluminium treatment affected the antioxidant
gene expression and induced oxidative stress in pea plant. 相似文献
14.
Iron toxicity occurs under flooded conditions such as those prevailing in lowland rice fields and is due to an excess of ferrous ions. Ferritin is a multimeric protein responsible for Fe sequestration and storage, playing a key role in Fe homeostasis. Our aim was to study the modalities of overall ferritin synthesis in different organs of young seedlings from the African rice species (Oryza glaberrima) in relation to the putative involvement of abscisic acid (ABA) and oxidative stress in signalling processes. Seedlings from a moderately resistant to iron toxicity cultivar were grown in hydroponic culture for 2 weeks and treated with 500 mg l?1 Fe2+ in the presence or in the absence of 200?µM ABA, 50?µM methylviologen or 50?µM fluridone. Iron treatment increased iron and malondialdehyde concentration in all organs as well as ABA in roots and laminae. Although ferritin protein was detected in controls plants, iron treatment strongly reinforced its accumulation in sheaths and laminae after 24 h and 72 h. Ferritin mRNA was induced as early as 24 h after the beginning of the Fe-treatment in sheaths and, to a higher extent, in laminae. In the absence of iron treatment, exogenous ABA increased ferritin mRNA in laminae only but did not lead to further ferritin accumulation. Unexpectedly, it decreased ferritin mRNA levels in the sheaths of iron-treated plants and may thus have a dual influence depending on the considered organ. The inhibitor of ABA synthesis fluridone reduced endogenous ABA but did not compromise ferritin gene expression or ferritin synthesis, whatever the iron dose. Methyviologen application induced obvious oxidative damages but reduced ferritin synthesis. It is suggested that the signalling pathway leading to ferritin synthesis in the semi-aquatic African rice species may involve other components than those reported for typical terrestrial plants. 相似文献
15.
In this study, we examined the modulation of Cu toxicity-induced oxidative stress by excess supply of iron in Zea mays L. plants. Plants receiving excess of Cu (100 μM) showed decreased water potential and simultaneously showed wilting in the
leaves. Later, the young leaves exhibited chlorosis and necrotic scorching of lamina. Excess of Cu suppressed growth, decreased
concentration of chloroplastic pigments and fresh and dry weight of plants. The activities of peroxidase (EC 1.11.1.7; POD),
ascorbate peroxidase (EC 1.11.1.11; APX) and superoxide dismutase (EC 1.15.1.1; SOD) were increased in plants supplied excess
of Cu. However, activity of catalase (EC 1.11.1.6; CAT), was depressed in these plants. In gel activities of isoforms of POD,
APX and SOD also revealed upregulation of these enzymes. Excess (500 μM)-Fe-supplemented Cu-stressed plants, however, looked
better in their phenotypic appearance, had increased concentration of chloroplastic pigments, dry weight, and improved leaf
tissue water status in comparison to the plants supplied excess of Cu. Moreover, activities of antioxidant enzymes including
CAT were further enhanced and thiobarbituric acid reactive substance (TBARS) and H2O2 concentrations decreased in excess-Fe-supplemented Cu-stressed plants. In situ accumulation of H2O2, contrary to that of O2
·− radical, increased in both leaf and roots of excess-Cu-stressed plants, but Cu-excess plants supplied with excess-Fe showed
reduced accumulation H2O2 and little higher of O2
·− in comparison to excess-Cu plants. It is, therefore, concluded that excess-Cu (100 μM) induces oxidative stress by increasing
production of H2O2 despite of increased antioxidant protection and that the excess-Cu-induced oxidative damage is minimized by excess supply
of Fe. 相似文献
16.
Ramírez-Benítez JE Muñoz-Sánchez JA Becerril-Chi KM Miranda-Ham Mde L Castro-Concha LA Hernández-Sotomayor SM 《Journal of inorganic biochemistry》2011,105(11):1523-1528
The accumulation of reactive oxygen species (ROS) and concomitant oxidative stress have been considered deleterious consequences of aluminum toxicity. However, several lines of evidence suggest that ROS can function as important signaling molecules in the plant defense system for protection from abiotic stress and the acquisition of tolerance. The role of ROS-scavenging enzymes was assayed in two different coffee cell suspension lines. We treated L2 (Al-sensitive) and LAMt (Al-tolerant) Coffea arabica suspension cells with 100 μM AlCl3 and observed significant differences in catalase activity between the two cell lines. However, we did not observe any differences in superoxide dismutase or glutathione reductase activity in either cell line following Al treatment. ROS production was diminished in the LAMt cell line. Taken together, these results indicate that aluminum treatment may impair the oxidative stress response in L2 cells but not in LAMt cells. We suggest a possible role for Al-induced oxidative bursts in the signaling pathways that lead to Al resistance and protection from Al toxicity. 相似文献
17.
18.
Calabrese V Cornelius C Maiolino L Luca M Chiaramonte R Toscano MA Serra A 《Neurochemical research》2010,35(12):2208-2217
Ménière’s disease (MD) is characterized by the triad of fluctuating hearing loss, episodic vertigo and tinnitus, and by endolymphatic
hydrops found on post-mortem examination. Increasing evidence suggests that oxidative stress is involved in the development
of endolymphatic hydrops and that cellular damage and apoptotic cell death might contribute to the sensorineural hearing loss
found in later stages of MD. While excess reactive oxygen species (ROS) are toxic, regulated ROS, however, play an important
role in cellular signaling. The ability of a cell to counteract stressful conditions, known as cellular stress response, requires
the activation of pro-survival pathways and the production of molecules with anti-oxidant, anti-apoptotic or pro-apoptotic
activities. Among the cellular pathways conferring protection against oxidative stress, a key role is played by vitagenes,
which include heat shock proteins (Hsps) as well as the thioredoxin/thioredoxin reductase system. In this study we tested
the hypothesis that in MD patients measurable increases in markers of cellular stress response and oxidative stress in peripheral
blood are present. This study also explores the hypothesis that changes in the redox status of glutathione, the major endogenous
antioxidant, associated with abnormal expression and activity of carbonic anhydrase can contribute to increase oxidative stress
and to disruption of systemic redox homeostasis which can be associated to possible alterations on vulnerable neurons such
as spiral ganglion neurons and consequent cellular degeneration. We therefore evaluated systemic oxidative stress and cellular
stress response in patients suffering from Meniere’s disease (MD) and in age-matched healthy subjects. Systemic oxidative
stress was estimated by measuring protein oxidation, such as protein carbonyls (PC) and 4-hydroxynonenal (HNE) in lymphocytes
of MD patients, as well as ultraweak luminescence (UCL) as end-stable products of lipid oxidation in MD plasma and lymphocytes,
as compared to age-matched controls, whereas heat shock proteins Hsp70 and thioredoxin (Trx) expression were measured in lymphocytes
to evaluate the systemic cellular stress response. Increased levels of PC (P < 0.01) and HNE (P < 0.05) have been found in lymphocytes from MD patients with respect to control group. This was paralleled by a significant
induction of Hsp70, and a decreased expression of Trx (P < 0.01), whereas a significant decrease in both plasma and lymphocyte ratio reduced glutathione GSH) vs. oxidized glutathione
(GSSG) (P < 0.05) were also observed. In conclusion, patients affected by MD are under condition of systemic oxidative stress and the
induction of vitagenes Hsp70 is a maintained response in counteracting the intracellular pro-oxidant status generated by decreased
content of GSH as well as expression of Trx. The search for novel and more potent inducers of vitagenes will facilitate the
development of pharmacological strategies to increase the intrinsic capacity of vulnerable ganglion cells to maximize antidegenerative
mechanisms, such as stress response and thus cytoprotection. 相似文献
19.
The role of glutathione and other antioxidant systems in the response of Escherichia coli to acetamidophenol (paracetamol), rifampicin, and chloramphenicol was studied. The exposure of aerobically growing E. coli cells to acetamidophenol diminished the intracellular level of glutathione by 40% and the reduced-to-oxidized glutathione ratio in the cells by 50%, while it enhanced the expression of the antioxidant genes soxS and sodA by 2.7 and 1.8 times, respectively. Glutathione-deficient cells were more susceptible to acetamidophenol than were normal cells. All this suggests that acetamidophenol induces a mild oxidative stress in E. coli cells. The oxidative stress induced by rifampicin was still less pronounced, whereas chloramphenicol-treated E. coli cells exhibited no signs of oxidative stress at all.__________Translated from Mikrobiologiya, Vol. 74, No. 2, 2005, pp. 149–156.Original Russian Text Copyright © 2005 by Smirnova, Torkhova, Oktyabrskii 相似文献
20.
Q. H. Yuan G. X. Shi J. Zhao H. Zhang Q. S. Xu 《Russian Journal of Plant Physiology》2009,56(4):495-502
In this study, physiological, biochemical, and proteomic changes of Alternanthera philoxeroides leaves under zinc stress were investigated. Zinc is an essential micronutrient for plants, but it can be toxic at higher
concentrations. Accumulations of zinc and MDA in leaves increased significantly with the increase of zinc concentrations.
Zn considerably changed the activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). Zn also
altered the antioxidant level, such as reduced glutathione (GSH) and ascorbic acid (AsA). Therefore, it seems that zinc induced
oxidative stress in the leaves of A. philoxeroides, in which we found enhancement of antioxidant enzyme activities and antioxidant concentrations. Protein profiles analyzed
by two-dimensional electrophoresis revealed that five protein spots were up-regulated in zinc-treated samples. These differentially
displayed proteins were identified by mass spectrometry. The up-regulation of some antioxidant enzymes and stress-related
proteins clearly indicated that excess zinc generates oxidative stress that might be disruptive to other important metabolic
processes. These results indicate a good correlation between the physiological and biochemical changes in A. philoxeroides leaves exposed to excess zinc.
Published in Russian in Fiziologiya Rastenii, 2009, Vol. 56, No. 4, pp. 546–554.
This text was submitted by the authors in English. 相似文献