Efficiency Of Antioxidant System Research Articles

The effect of DMSO on Saccharomyces cerevisiae yeast with different energy metabolism and antioxidant status

We studied the effect of dimethyl sulfoxide (DMSO) on the biochemical and physiological parameters of S. cerevisiae yeast cells with varied energy metabolism and antioxidant status. The wild-type cells of varied genetic backgrounds and their isogenic mutants with impaired antioxidant defences (Δsod mutants) or response to environmental stress (ESR) (Δmsn2, Δmsn4 and double Δmsn2msn4 mutants) were used. Short-term exposure to DMSO even at a wide range of concentrations (2–20%) had little effect on the metabolic activity of the yeast cells and the stability of their cell membranes, but induced free radicals production and clearly altered their proliferative activity. Cells of the Δsod1 mutant showed greater sensitivity to DMSO in these conditions. DMSO at concentrations from 4 to 10–14% (depending on the strain and genetic background) activated the ESR programme. The effects of long-term exposure to DMSO were mainly depended on the type of energy metabolism and antioxidant system efficiency. Yeast cells with reduced antioxidant system efficiency and/or aerobic respiration were more susceptible to the toxic effects of DMSO than cells with a wild-type phenotype and respiro-fermentative or fully fermentative metabolism. These studies suggest a key role of stress response programs in both the processes of cell adaptation to small doses of this xenobiotic and the processes related to its toxicity resulting from large doses or chronic exposure to DMSO.

Efficiency of antioxidant system in barrel medic (

Iron (Fe) deficiency leads to an overproduction of reactive oxygen species (ROS) in plants that activate their antioxidant systems to control oxidative burst. In this study, contrasting Medicago truncatula genotypes, A17 and TN8.20 (tolerant) and TN1.11 (sensitive), were grown under Fe deficiency. The superoxide dismutase (SOD: EC1.15.1.1) activity, their isoforms’ coding genes, the copper chaperone expression patterns, and leaf phenolic contents were analysed. Our results showed that Fe deficiency decreases the photosynthetic capacity and plant biomass production with a prominent effect on TN1.11 genotype. The tolerance of A17 and TN8.20 was correlated with a maintenance of Fe content and the photosynthetic apparatus and an increase of Cu concentration compared with the sensitive genotype. We revealed a significant increase of H2O2 in Fe-deficient plants, mainly in TN1.11 sensitive genotype. TN8.20 and A17 tolerance were concomitant with a significant increase of SOD activities (SOD, Cu/Zn-SOD, and Mn-SOD) under Fe deficiency. This increment was correlated to an induction of the copper chaperone gene expression level, as well as an accumulation of isoquercitin phenolic compound. Our study provides new insights into the orchestration of SOD’s isoforms activities, the expression of the copper chaperone, FeSOD, Cu/ZnSOD genes, and the leaf phenolic compounds accumulation that allows Medicago truncatula to overcome Fe deficiency.

EDS1-Dependent Cell Death and the Antioxidant System in Arabidopsis Leaves is Deregulated by the Mammalian Bax.

Cell death is the ultimate end of a cell cycle that occurs in all living organisms during development or responses to biotic and abiotic stresses. In the course of evolution, plants and animals evolve various molecular mechanisms to regulate cell death; however, some of them are conserved among both these kingdoms. It was found that mammalian proapoptotic BCL-2 associated X (Bax) protein, when expressed in plants, induces cell death, similar to hypersensitive response (HR). It was also shown that changes in the expression level of genes encoding proteins involved in stress response or oxidative status regulation mitigate Bax-induced plant cell death. In our study, we focused on the evolutional compatibility of animal and plant cell death molecular mechanisms. Therefore, we studied the deregulation of reactive oxygen species burst and HR-like propagation in Arabidopsis thaliana expressing mammalian Bax. We were able to diminish Bax-induced oxidative stress and HR progression through the genetic cross with plants mutated in ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1), which is a plant-positive HR regulator. Plants expressing the mouse Bax gene in eds1-1 null mutant background demonstrated less pronounced cell death and exhibited higher antioxidant system efficiency compared to Bax-expressing plants. Moreover, eds1/Bax plants did not show HR marker genes induction, as in the case of the Bax-expressing line. The present study indicates some common molecular features between animal and plant cell death regulation and can be useful to better understand the evolution of cell death mechanisms in plants and animals.

The Relationship between the Level of Anterior Cingulate Cortex Metabolites, Brain-Periphery Redox Imbalance, and the Clinical State of Patients with Schizophrenia and Personality Disorders.

Schizophrenia is a complex mental disorder whose course varies with periods of deterioration and symptomatic improvement without diagnosis and treatment specific for the disease. So far, it has not been possible to clearly define what kinds of functional and structural changes are responsible for the onset or recurrence of acute psychotic decompensation in the course of schizophrenia, and to what extent personality disorders may precede the appearance of the appropriate symptoms. The work combines magnetic resonance spectroscopy imaging with clinical evaluation and laboratory tests to determine the likely pathway of schizophrenia development by identifying peripheral cerebral biomarkers compared to personality disorders. The relationship between the level of metabolites in the brain, the clinical status of patients according to International Statistical Classification of Diseases and Related Health Problems, 10th Revision ICD-10, duration of untreated psychosis (DUP), and biochemical indices related to redox balance (malondialdehyde), the efficiency of antioxidant systems (FRAP), and bioenergetic metabolism of mitochondria, were investigated. There was a reduction in the level of brain N-acetyl-aspartate and glutamate in the anterior cingulate gyrus of patients with schisophrenia compared to the other groups that seems more to reflect a biological etiopathological factor of psychosis. Decreased activity of brain metabolites correlated with increased peripheral oxidative stress (increased malondialdehyde MDA) associated with decreased efficiency of antioxidant systems (FRAP) and the breakdown of clinical symptoms in patients with schizophrenia in the course of psychotic decompensation compared to other groups. The period of untreated psychosis correlated negatively with glucose value in the brain of people with schizophrenia, and positively with choline level. The demonstrated differences between two psychiatric units, such as schizophrenia and personality disorders in relation to healthy people, may be used to improve the diagnosis and prognosis of schizophrenia compared to other heterogenous psychopathology in the future. The collapse of clinical symptoms of patients with schizophrenia in the course of psychotic decompensation may be associated with the occurrence of specific schizotypes, the determination of which is possible by determining common relationships between changes in metabolic activity of particular brain structures and peripheral parameters, which may be an important biological etiopathological factor of psychosis. Markers of peripheral redox imbalance associated with disturbed bioenergy metabolism in the brain may provide specific biological factors of psychosis however, they need to be confirmed in further studies.

Antioxidant Efficiency ofPlatynereisspp. (Annelida, Nereididae) under Different pH Conditions at aCO2Vent’s System

Marine organisms are exposed to a pH decrease and to alteration of carbonate chemistry due to ocean acidification (OA) that can represent a source of oxidative stress which can significantly affect their antioxidant defence systems efficiency. The polychaetesPlatynereis dumeriliiandP. massiliensis(Nereididae) are key species of the benthic community to investigate the effect of OA due to their physiological and ecological characteristics that enable them to persist even in naturally acidified CO2vent systems. Previous studies have documented the ability of these species to adapt to OA after short- and long-term translocation experiments, but no one has ever evaluated the basal antioxidant system efficiency comparing populations permanently living in habitat characterized by different pH conditions (acidifiedvs.control). Here, individuals of bothPlatynereisspecies, sampled from a natural CO2vent system and from a nonventing “control” site in three different periods (April 2016, October 2016, and February 2017), were compared highlighting signals which suggested the ability of both species to acclimatize to highpCO2–low pH with slight seasonal variations of their antioxidant efficiency and the absence of disturbances of the oxidative status ofPlatynereisspp. tissues.

Overexpression of PeHKT1;1 Improves Salt Tolerance in Populus.

Soil salinization is an increasingly serious threat that limits plant growth and development. Class I transporters of the high-affinity K+ transporter (HKT) family have been demonstrated to be involved in salt tolerance by contributing to Na+ exclusion from roots and shoots. Here, we isolated the PeHKT1;1 gene from hybrid poplar based on the sequences of the Populus trichocarpa genome. The full-length PeHKT1;1 gene was 2173 bp, including a 1608 bp open reading frame (ORF) encoding 535 amino acids and containing eight distinct transmembrane domains. Multiple sequence alignment and phylogenetic analysis suggested that the PeHKT1;1 protein had a typical S–G–G–G signature for the P-loop domains and belonged to class I of HKT transporters. PeHKT1;1 transcripts were mainly detected in stem and root, and were remarkably induced by salt stress treatment. In further characterization of its functions, overexpression of PeHKT1;1 in Populus davidiana × Populus bolleana resulted in a better relative growth rate in phenotypic analysis, including root and plant height, and exhibited higher catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activities than non-transgenic poplar under salt stress conditions. These observations indicated that PeHKT1;1 may enhance salt tolerance by improving the efficiency of antioxidant systems. Together, these data suggest that PeHKT1;1 plays an important role in response to salt stress in Populus.

Copper-induced changes in nutrient uptake, enzymatic and non-enzymatic antioxidant systems in horehound ( Marrubium vulgare L.)

Background: The effect of different concentrations (80, 200 and 300 mg/L) of copper (Cu2+) on physiological parameters of horehound ( Marrubium vulgare L.) was studied. Once Horehound was cultivated in pots, element uptake and antioxidant system efficiency have been evaluated.Questions: What is the effect of copper on the physiological parameters of Marrubium vulgare ? What are the defense strategies developed by this plant to overcome cupric stress?Species study: horehound ( M. vulgare ) medicinal plant from the family of Lamiaceae.Study site and dates: Seeds of M. vulgare were issued from a non contaminated wild population in the region of Béja (Northwestern Tunisia). Culture of M. vulgare was conducted in 1 August 2014 and lasted 4 months.Methods: The Cu, Fe, K, Mg and Ca contents have been determined. Total phenolic and flavonoid contents have been determined. The free radical scavenging activity (DPPH test) together with SOD, CAT and APX antioxidant enzymatic activity have been evaluated.Results: In the aerial part extracts, Copper stress reduced the uptake and translocation of the cationic elements Fe2+, K+ and Ca2+, in a Cu2+ concentration-dependent manner. The treatment with copper gives rise to positive effects on antioxidant enzymes activities (SOD and CAT enzymes) and to an increase of total phenol and flavonoid contents. Unexpectedly, no correlation with the anti-radical scavenging activity was observed.Conclusions: M. vulgare possess an intrinsic capability to cope with the Cu stress by activation of the enzymatic and non-enzymatic antioxidant systems.

Regulation of the oxidative processes as a possible mechanism of iron nanoparticles antitumor action.

e23160 Background: It has been shown that metal nanoparticles (NPs) can inhibit a tumor growth. Oxidative processes play important roles in tumor development and growth. The aim of this study was to determine parameters of oxidative stress in the blood of tumor-bearing animals depending on the antitumor effect of iron NPs (30-50 nm). Methods: Male rats with transplantable lymphosarcoma (LS) in the main group (n = 21) were treated with eight i.p. injections of iron NPs (total doses of 10 mg/kg bw), the control LS rats (n = 20) received saline i.p. The activity of catalase, superoxide dismutase (SOD), content of glutathione (GSH) and malondialdehyde (MDA) in the red blood cells (RBC) and ceruloplasmin oxidase activity (CP) and MDA content in blood plasma were measured. These parameters were analyzed in rats with complete tumor regression (n = 12) after NPs treated and in cases of tumor growth (n = 9). Results: In RBC of control group the level of GSH and catalase activity were increased compared to healthy rats by 24% and 14.3% (p < 0.05), respectively. In spite of activation of the given antioxidant system components, the MDA content in RBC was increased by 45% (p < 0.01) compared to normal values. In plasma of control group we observed an increase in MDA by 167.4% (p < 0.01) and a decrease in CP by 36.8% (p < 0.001). In the main group there was a decrease in blood MDA level and the antioxidant system reorganization. The degree of changes depended on the antitumor effect of NPs: rats with tumor growth showed a tendency to the decreasing MDA in RBC and normalization of plasma MDA; MDA in rats with LS regression was similar to normal values. In the main group the CP activity did not differ from the values in healthy rats. GSH increased in animals with tumor growth by 218.6% and in the animals with the effect - by 69% compared to normal values (p < 0.01). SOD activity in the rats with LS growth increased by 42% and in the rats with LS regression it decreased by 30% (p < 0.01). Conclusions: The data suggest the relationship between antitumor effect and modulating action on oxidative processes in LS rats treated by iron NPs. Iron NPs improved efficiency of antioxidant system in blood and contributed to suppression of oxidative stress associated with tumor growth.

Responses of antioxidant gene and enzymes to salinity stress in the Cuminum cyminum L.

Salt stress as a major limiting factor negatively affects many physiological processes in plants. Salinity promotes the generation of reactive oxygen species and subsequently oxidative damage of cellular components. Plant salt stress tolerance requires activation of antioxidative pathways to prevent plant cell from injurious effects. In this study real-time quantitative reverse transcription–polymerase chain reaction was used to determine the protective role of two antioxidant genes, i.e. iron-superoxide dismutase (Fe-SOD) and catalase (CAT) in Cuminum cyminum L. after their treatment with 50, 100, 150 and 200 mM NaCl. Enzymatic activities were assayed spectrophotometrically for three antioxidants. Moreover, growth parameters, protein content and proline accumulation were measured. In comparison with the control plants, those plants which were exposed to 50 and 100 mM NaCl concentration accumulated higher levels of proline. At 50, 100 and 150 mM of NaCl plants showed higher superoxide dismutase, ascorbate peroxidase and catalase activities. The same condition also induced expression of the Fe-SOD and CAT genes at mRNA level. Protein content of the treated plants was significantly decreased at 50 mM NaCl and remained constant at other concentrations. Whereas, the growth parameters, with one exception in case of shoot length, did not change at plants receiving low and mild salt concentrations of up to 150 mM NaCl, 200 mM of NaCl affected these parameters negatively. From these details, it can be concluded that C. cyminum respond to salt stress by antioxidant system efficiency and proline accumulation.

Accelerated ageing and subsequent imbibition affect seed viability and the efficiency of antioxidant system in macaw palm seeds

Accelerated ageing is an accurate test indicator of seed vigor and storability that helps to understand the mechanisms of cellular and biochemical deterioration that occur during seed ageing. This study was carried out to elucidate the mechanisms of ageing in macaw palm embryos. Seeds were artificially aged during 4, 8 and 12 days at 45 °C and 100% relative humidity. After ageing, seeds were tested for viability (tetrazolium), electrical conductivity, lipid peroxidation (MDA) and hydrogen peroxide (H2O2) content. Part of the aged seeds was imbibed for 8 days and then determined the hydrogen peroxide content and the activity of antioxidant system enzymes (superoxide dismutase, catalase and glutathione reductase). Ageing reduced the embryo viability from 8 days of treatment and increased malondialdehyde content (MDA) and solute leakage. Hence, membrane permeability correlated with both loss of viability and lipid peroxidation. Imbibition after ageing significantly increased H2O2 content along with superoxide dismutase activity. Catalase activity was significantly higher than control in embryos aged from 8 days and imbibed, and glutathione reductase activity did not change. Our results suggest that macaw palm seed deterioration during accelerated ageing is closely related to lipid peroxidation, and that enzymatic antioxidant system is not completely efficient in reducing reactive oxygen species after imbibition, a critical phase to germination. Moreover, accelerated ageing test can be used as a reliable model to understand the mechanisms involved in palm seeds deterioration.

Effects of Nanomaterials on Oxidative Stress and Protein Oxidation in Biological System: Biochemical and Biological Aspects

Oxidation and reduction is a ubiquitous phenomenon reflecting the structural, functional aspects of cell, tissue, organ and organism. Primarily oxidative process in a biological system is the imprint of structural and functional integrity because of its role to maintain a state of healthy equilibrium. This homeostatic state is the result of combined and coordinated interactions between pro oxidants, antioxidants, inactivated free radicals and oxidants present in the cell. Proteins alone and in conjugated from are amongst those biomolecules which are basically devoted to cellular structural, functional, inter and intracellular communication. Electrochemical aspects of oxidation reduction are applicable to the oxidation of proteins. High energy radiations are capable to form free radicals of oxygen, when proteins are exposed to such free radicals gross modifications in amino acids and/or fragmentation of proteins occurs. Redox metabolism reflects on the functional aspects of proteome; there is every probability that any temporal and spatial fluctuations can direct the functional aspect of cell. Conditions like resistance to insulin, dysfunction of immune system and inflammatory responses are concerned with oxidative stress. Diseased conditions and senescence are parameters directly related to the declined efficiency of antioxidant system indicating oxidative stress. This in turn is capable to causes modifications in DNA, carbohydrates, proteins and lipids. In the recent past nanotechnology has attained significant importance due to its multidimensional potentials in almost all fields of life. The nanomaterials, natural as well as engineered, are sought after to solve most of the problems related to man-kind and industries. The physicochemical properties of nanomaterials are the basis of their applications in all spheres of life. In this presentation an effort is made to over view the developments in the field of nanomaterials that have taken place in the recent past and more over their impact on redox process and protein oxidation encompassing biological, biochemical, physiological, and pathological aspects in a biological system.

Salivary antioxidants of male athletes after aerobic exercise and garlic supplementation on: A randomized, double blind, placebo-controlled study

PurposeProduction of reactive oxygen species and reactive nitrogen species is a natural biological event in metabolism. However, the presence of antioxidants can highly reduce the negative effect of free radicals. Thus, the efficiency of antioxidant system in the physiology of exercise is very important. DesignConsidering the known antioxidant capacity of garlic, the purpose of this study was to evaluate the effect on combining 14 days aerobic exercise till exhaustion with garlic extract supplementation on the antioxidant capacity of saliva. MethodsSixteen young men volunteered to participate in this randomized, double blind, placebo-controlled study and were randomly placed into two groups, placebo (Group I) and garlic extract (Group II). The participants performed exhaustive aerobic exercise on a treadmill before and after supplementation. Their unstimulated salivary samples were collected before, immediately after, and 1h after the activity. The antioxidant activity in terms of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) was then measured in the collected samples using their specific substrates. ResultsA significant increase in salivary antioxidant activity of SOD, POD, and CAT was observed in saliva of the supplement group compared to the placebo group (P≤0.05). ConclusionThe findings from this study suggest that increased activity of antioxidant enzymes could possibly decrease exercise-induced oxidative damage in male athletes.

CONTENT OF REDUCED GLUTATHIONE FORM AS A BIOMARKER OF OXIDATIVE STRESS IN SPINACH PLANTS GROWING IN SOIL CONTAMINATED WITH ZINC

The aim of the paper is the assessment of the efficiency of anti-oxidative system in spinach plants growing in the substratum polluted with zinc. The assessment was conducted on the basis of changes of reduced glutathione (GSH) form concentration in the plant aboveground organs. Spinach plants, ‘Matador’ c.v., were cultivated in soils contaminated with zinc in two pot experiments conducted in 2010 and 2011. The experimental substratum was light, slightly soil with granulometric composition of sandy silt loam. Zinc in the acetate form, was supplied to the soil in four doses corresponded to this metal critical concentrations in soil with 0, I, II and III degrees of pollution with this element according to IUNG classification. Simultaneously, the control with natural Zn content in soil was maintained. Zn concentrations in spinach ranged from 412.8 to 1722 mg ∙ kg -1 d.m. and increased with growing degree of substratum pollution with this element. Over the course of the vegetation period the content of Zn in plants was generally greater. GSH content in spinach grown in both years of experiments fluctuated from 31.70 to 238 µg ∙ g -1 f.m. The biggest content of this compound in spinach was stated in the initial phase of plants growth. The plants tolerated only the first two Zn doses supplied to the substratum. Spinach growing in the objects where zinc additions to the soil equalled II and III degree of substratum pollution died shortly after germination. The plants from these objects in the initial growth phase contained significantly less GSH than spinach from the objects with two first degrees (0 and I) of substratum pollution with zinc or from the control. The content of reduced glutathione form in spinach is a good biomarker of oxidative stress caused by zinc presence in plants. Synthesis of a bigger amount of GSH conditions spinach plant resistance to over the norm zinc content in soil. The efficiency of anti-oxidative system in spinach is bigger in the initial phase of this plant growth.

尖叶拟船叶藓(Dolichomitriopsis diversiformis)光合荧光特性、活性氧代谢与耐脱水生理生态适应性的关系

PDF HTML阅读 XML下载 导出引用 引用提醒 尖叶拟船叶藓光系统Ⅱ光合荧光特性、活性氧代谢与耐脱水生理生态适应的关系 DOI: 10.5846/stxb201303060358 作者: 作者单位: 湖南吉首大学生物资源与环境科学学院,湖南吉首大学生物资源与环境科学学院,湖南吉首大学生物资源与环境科学学院,湖南吉首大学生物资源与环境科学学院,植物资源保护与利用湖南省高校重点实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(30470181,31360062);湖南省教育厅优秀青年项目(09B082);湖南省重点学科建设项目(JSU0713Z11);湖南省高校科技创新团队支持计划(201208Z02) Influence of dehydration and rehydration on photosynthetic chlorophyll characteristics and reactive oxygen species metabolism in Dolichomitriopsis diversiformis Author: Affiliation: School of Biology and Environmental Science,Jishou University,Jishou Hunan,School of Biology and Environmental Science,Jishou University,Jishou Hunan,School of Biology and Environmental Science,Jishou University,Jishou Hunan,School of Biology and Environmental Science, Jishou University, Jishou Hunan,Key Laboratory of Plant Resources Conservation and Utilization,College of Hunan Province,Jishou Hunan China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以广布湿生藓类——湿地匐灯藓(Plagiomnium acutum)为比较材料,研究东亚特有濒危植物尖叶拟船叶藓 (Dolichomitriopsis diversiformis) 在不同快速脱水和复水胁迫下PSⅡ的叶绿素光合荧光变化和活性氧代谢及抗氧化系统变化,探讨两种藓类生理生态适应性差异的成因,以初步确定尖叶拟船叶藓受水分条件限制分布狭窄趋于濒危的原因。结果显示:(1)尖叶拟船叶藓的光合电子传递在脱水后可被极微弱光完全抑制,其抑制光强的恢复明显慢于湿地匐灯藓;其PSⅡ最大光化学效率(Fv/Fm)和实际光化学量子效率(YⅡ)先降而后升,恢复较慢;光化学淬灭(qP)复水后恢复较快,非光化学淬灭(NPQ)的绝对值和变化速率则始终低于湿地匐灯藓。(2)尖叶拟船叶藓活性氧水平明显高于湿地匐灯藓;其SOD、CAT、APX等抗氧化系统酶活性整体变化幅度较大,抗氧化保护物质(AsA)含量则明显低于湿地匐灯藓。以上结果表明尖叶拟船叶藓受到环境水分因子限制的原因主要有:(1)PSⅡ的反应中心色素(P680)对脱水伤害较为敏感;(2)复水修复过程中抗氧化保护系统的保护能力偏低。 Abstract:Dolichomitriopsis diversiformis, an endangered moss species which is unique to East Asia, is now distributed in a very narrow area. From our early field investigation of its habitat, we found that the species is restricted by moisture content of atmosphere and growth matrix. In order to disclose the endangered mechanism of D. diversiformis under water stress, and to elucidate eco-physiological differences of bryophytes in similar humidity habitat, Plagiomnium acutum, a widespread species was selected to compare with D. diversiformis. Therefore, their photosynthetic chlorophyll characteristics of phtosystem Ⅱ (PSⅡ), such as electron transport rate (ETR)- photosynthetic available radiation (PAR) curves, maximal photochemical efficiency(Fv/Fm), photosystem quantum yielding (Y(Ⅱ)), photochemical qunching (qP) and non-photochemical qunching (NPQ) were detected by PAM 2500 and IMAGING PAM. Furthermore, metabolism of reactive oxygen species (superoxide anion and hydrogen peroxide), activities of antioxidative enzymes (superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX)) and content of ascorbic acid (ASA) in the two moss species during desiccation and rehydration were determined in our studies. Results of ETR-PAR curve indicated that desiccation reduced the inhibitory light density of both species; but when water content recovered, the inhibitory light density restored to normal status. Compared with P. acutum, ETR of D. diversiformis was blocked completely by very weak light density after 60 min dehydration and recovered much more slowly in rehydration. And the results of other PSⅡ chlorophyll fluorescence characters also gave similar evidences. Fv/Fm and YⅡ of both bryophytes were decreased under desiccation and then increased in rehydraion, but the value of D. diversiformis declined more quickly during desiccation and recovered more slowly in rehydration. That is to say, photosynthetic electron transport of PSⅡ in D. diversiformis can be not only reduced by water loss but also destroyed completely by deep desiccation. Meanwhile, variation of qP and NPQ of both species manifested an interesting occurance. qP of D. diversiformis declined more quickly than P. acutum in desiccation and returned to normal condition much more quickly than that of P. acutum. In other words, photosynthetic reaction which is represented by photochemical qunching is protected primarily in D. diversiformis. But photochemical quenching restoration would bring out more production of reactive oxygen species. Otherwise, though NPQ of both species increased in desiccation and decrease in rehydration, yet the absolute value of D. diversiformis maintained a relative low level. These results suggested that the photo-protective mechanism supported by xanthophyll cycle in D. diversiformis should be weaker than in P. acutum. All these results indicate that PSⅡ of D. diversiformis, especially reaction central pigment (P680) is more sensitive to dehydration than P. acutum. Results of reactive oxygen species metabolism showed that absolute value of superoxide anion production and hydrogen peroxide content in D. diversiformis were significantly higher than in P. acutum. Furthermore, though anti-oxidative enzymes, such as SOD, CAT, APX also increased similar of reactive oxygen species under desiccation, yet their activities in D. diversiformis decreased more quickly in rehydration. In conclusion, the sensitivity of photosystem Ⅱ and the low efficiency of antioxidative system in rehydration are probably two major eco-physiological restricting factors of D. diversiformis narrow distribution. 参考文献 相似文献 引证文献

Evaluation of antioxidant enzymes activities and identification of intermediate products during phytoremediation of an anionic dye (C.I. Acid Blue 92) by pennywort (Hydrocotyle vulgaris)

The potential of pennywort (Hydrocotyle vulgaris) for phytoremediation of C.I. Acid Blue 92 (AB92) was evaluated. The effects of various experimental parameters including pH, temperature, dye concentration and plant weight on dye removal efficiency were investigated. The results showed that the optimal condition for dye removal were pH 3.5 and temperature 25°C. Moreover, the absolute dye removal enhanced with increase in the initial dye concentration and plant weight. Pennywort showed the same removal efficiency in repeated experiments (four runs) as that obtained from the first run (a 6-day period). Therefore, the ability of the plant in consecutive removal of AB92 confirmed the biodegradation process. Accordingly, a number of produced intermediate compounds were identified. The effect of treatment on photosynthesis and antioxidant defense system including superoxide dismutase, peroxidase and catalase in plant roots and leaves were evaluated. The results revealed a reduction in photosynthetic pigments content under dye treatments. Antioxidant enzyme responses showed marked variations with respect to the plant organ and dye concentration in the liquid medium. Overall, the increase in antioxidant enzyme activity under AB92 stress in the roots was much higher than that in the leaves. Nevertheless, no significant increase in malondialdehyde content was detected in roots or leaves, implying that the high efficiency of antioxidant system in the elimination of reactive oxygen species. Based on these results, pennywort was founded to be a capable species for phytoremediation of AB92-contaminated water, may be effective for phytoremediation dye-contaminated polluted aquatic ecosystems.

Potential of Hydrocotyle vulgaris for phytoremediation of a textile dye: Inducing antioxidant response in roots and leaves

The potential of Hydrocotyle vulgaris as an aquatic plant species was evaluated for phytoremediation of C.I. Basic Red 46 (BR46) from nutrient solution. Under the optimized experimental conditions, BR46 was removed up to 95% from incubation medium by H. vulgaris. The ability of the plant in consecutive removal under long term repetitive experiments confirmed the biodegradation process. Accordingly, a number of produced intermediate compounds were identified. An artificial neural network (ANN) model was developed to predict the biodegradation efficiency. A predictive performance (R2=0.974) was obtained based on the network results. Interestingly, dye stress enhanced the activity of antioxidant enzymes including superoxide dismutase, peroxidase and catalase in H. vulgaris roots and leaves. Enzymatic responses found to be highly depended on the plant organ and dye concentration in the liquid medium. Overall, the increase in the activity of antioxidant enzymes was much higher in the roots than in the leaves. Nevertheless, no significant increase in the malondialdehyde (MDA) content was detected in both roots and leaves which reflects the high efficiency of antioxidant system in the elimination of reactive oxygen species.

Efficiency of antioxidative system in spinach plants growing in soil contaminated with nickel

The paper attempted to assess the activity of antioxidative system in cells of spinach plant, ‘Matador’ c.v., growing in the soil contaminated with Ni. Plant material for analyses was obtained from two pot experiments conducted in 2010 and 2011 in the vegetation hall of the Experimental Station of the University of Agriculture in Krakow. Ni content in the plant aboveground parts was assessed by ICP-ES method, contents of reduced glutathione form by colorimetry and ascorbic acid by titrimetric method. Nickel content in spinach aboveground parts ranged from 2.00 to 204.5 mg kg d.m. and increased with growing substratum pollution with this element and usually with plant age. The plants contained from 31 to 238 g GSH g f.m. In the first three objects with 0, I and II degree of substratum pollution according to IUNG classification, this antioxidant contents were higher in comparison with its amount in plants from the control and objects with lower degree of pollution. In the object with the highest nickel dose application, GSH content in plants decreased significantly in comparison with plants from the other objects, while the plants on this object died shortly after germination. Ascorbic acid content in spinach in the both years of experiments ranged from 24.13 to 73.09 mg 100 g f.m. and increased in plants from the successive objects with growing substratum contamination with nickel. In the first phase of growth spinach plants contained generally much more of GSH and AsA, which indicated much better efficiency of the antioxidative system at the initial period of growth.

Effects of salicylic acid on monoterpene production and antioxidant systems in Houttuynia cordata

Salicylic acid (SA) plays important roles in plant defense responses. However, little is available about its effects on monoterpene responses. Therefore, monoterpene contents and antioxidant systems were measured three days after foliar application of SA with different concentrations in Houttuynia cordata . SA at low concentrations (≤ 1 mM) suitably enhanced the efficiency of antioxidant system, however, at high concentrations (10 and/or 100 mM), a strong accumulation of peroxidase, catalase and malondialdehyde suggested the induction of oxidative stress. High concentrations of SA resulted in a marked accumulation of total monoterpenes, which might be attributed to the oxidative burst. A significant increase in total monoterpene contents was also observed at 0.01 mM SA, which might be favorable for the induction of monoterpenes because of less oxidative damage to the plants. Total monoterpene contents showed a decline in the treatments of 0.1 and 1 mM SA. However, not all of monoterpene individuals were significantly induced and/or suppressed in the corresponding treatments. This implied that different monoterpenes might be differentially mediated at different concentrations of SA. Key words : Houttuynia cordata , monoterpenes, oxidative stress, salicylic acid.

Efeito de diferentes frequências semanais de treinamento sobre parâmetros de estresse oxidativo. DOI: 10.5007/1980-0037.2012v14n1p52

During the muscle contraction induced by exercises there is an increase in the reactive oxygen species production, causing oxidative stress in several organs, including liver and heart. The exercise may can increases antioxidant defenses and decrease oxidative stress in these organs. However, the number of the sessions a week necessary to improve the parameters of oxidative stress is not to well defined. The aim of the study was to investigate the frequency effects of exercise performed two and three times a week on changes in biomarkers of oxidative stress in the liver and heart. Were used 18 male mice (CF1), young (30 to 35g) and divided into groups (n=6/group): not trained (NT) trained twice a week (T2) and trained three times a week (T3). The animals were subjected to training for eight weeks. Forty-eight hours after the last session, the animals were killed. The liver and heart were removed and stored in - 70°C. Were analyzed the thiobarbituric acid reactive substances, protein carbonyls, content of total thiols, superoxide dismutase, catalase and glutathione peroxidase. Our findings showed that the group T3 reduced oxidative damage. There was increase in content of total thiols, superoxide dismutase and catalase in the T3 group when compared to NT. The glutathione peroxidase activity showed no significant difference between groups. This study demonstrated that only the frequency of training performed three times a week was able to reduces oxidative damage and increases the efficiency of antioxidant system of mice.

Oxidative Stress Effects on Endothelial Cells Treated with Different Athletes’ Sera

Exercise training is a nonpharmacological intervention that improves cardiovascular function and enhances endothelial homeostasis in patients with cardiovascular diseases. However, the amount of benefit achieved varies widely depending on the type and duration of exercise. Moreover, data about the long-term effects of physical activity are scarce. In this study, endothelial cells, exposed or not to oxidative stress, were conditioned with sera from athletes regularly participating in sports classified as "aerobic" (triathlon), "mixed aerobic-anaerobic" (soccer), and "anaerobic" (sprint running). Functional and hemodynamic variables did not differ between groups of athletes, whereas there were dramatic changes in serum markers for oxidative stress. Lipid peroxidation assessed by the thiobarbituric acid reactive substances assay and catalase activity were the lowest and nitric oxide availability was the highest in sera of triathletes. Endothelial cells cultured in serum from triathletes (T-endothelial cells) had the highest survival, evaluated by viability assay, BrdU incorporation, and senescence-associated β galactosidase assays, and preserved the endothelial appearance before and after stress in contrast to the cells grown in sera from the other athletes. T-endothelial cells also had the highest catalase messenger RNA expression and, after stress, the highest catalase activity of all the endothelial cells. Moreover, poststress activity of Sirt1, a NAD(+)-dependent deacetylase involved in cellular stress resistance and a key regulator of longevity, was significantly increased in T-endothelial cells. Different types of exercise training induced different molecular effects in terms of survival, morphology, and antioxidant system efficiency. The in vitro technique used herein may help to shed light on the molecular basis of effects of long-term physical activity in humans.