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1.
Environmental pollutants, such as metals, are widespread in aquatic environments and can lead to the formation of reactive oxygen species (ROS). ROS are highly toxic in marine species since they can cause serious reversible and irreversible changes in proteins including ubiquitination and modifications such as carbonylation. This study aimed to confirm the potential of ubiquitination and carbonylation as markers of oxidative stress in the clam Ruditapes decussatus (Veneroida, Veneridae) exposed to cadmium (40 microg/L). After 21 days of exposure clams were dissected into gills and digestive gland. Cytosolic proteins of both tissues were separated by two-dimensional electrophoresis (2-D SDS-PAGE) and analysed by immunobloting. Higher ubiquitination and carbonylation levels were in digestive gland of contaminated organisms. These results confirm the potential of ubiquitination and carbonylation as a sensitive and specific marker of oxidative stress in marine bivalves. In this approach, changes in protein structure provide options for affinity selection of sub-proteomes for 2D SDS-PAGE, simplifying the detection of protein biomarkers using proteomic approach.  相似文献   

2.
本实验以新月菱形藻为受试生物,研究了低浓度不同粒径TiO2颗粒(21nm、60nm和400nm)对海洋微藻生长、抗氧化酶活性(超氧化物歧化酶SOD、过氧化氢酶CAT和过氧化物酶POD)、脂质过氧化产物(MDA)含量的影响,并测定了相应的活性氧自由基(ROS)的含量,初步探讨了TiO2颗粒对海洋微藻的作用机制。结果表明,1mg/L TiO2颗粒对新月菱形藻生长的抑制作用随着粒径的减小而逐渐增强,第48h、72h、96h呈现出显著的纳米效应。TiO2颗粒可以诱导藻细胞内ROS的含量增加,对藻细胞产生氧化胁迫,新月菱形藻的抗氧化酶活性发生应激响应,以清除过量的ROS,但剩余的ROS对藻细胞产生氧化损伤,导致MDA含量升高,并且纳米级TiO2颗粒对新月菱形藻的氧化损伤大于微米级颗粒。在不同粒径TiO2颗粒的胁迫下,藻细胞SOD和CAT活性的响应也存在差异。本研究将为开展人工纳米材料对海洋生态系统影响的潜在风险评估提供科学依据。  相似文献   

3.
Oxidative stress induced by xenobiotic compounds has been studied using primary hepatocytes of juvenile European flounder (Platichthys flesus L.) caught in a low polluted area of the German Bight, Tiefe Rinne (Landwüst et al., 1996.). Cells were exposed to known oxidative stressors such as hydrogen peroxide and benzo[a]pyrene (B[a]p) in various concentrations (50 and 100 microM) up to 6 days. Cell mortality was determined using fluorescent ethidium homodimer-1 and calcein AM. Oxidative stress response was measured by image analysis using dihydrorhodamine 123, which is converted to fluorescent rhodamine 123 in the presence of intracellular ROS. Oxyradical formation was initiated already after 2 h of exposure to low concentrations of B[a]p and hydrogen peroxide. Probably due to a membrane stabilising effect of the serum factors the addition of fetal bovine serum to the culture medium had a protecting influence on the hepatocytes and resulted in (1) an increased cell viability and (2) reduced formation of intracellular ROS during exposure. In conclusion, the assay is a sensitive tool for testing the potential of various xenobiotics to induce oxidative stress in living hepatocytes.  相似文献   

4.
The present study aimed to obtain additional data on the effect of long-term depuration on the levels of oxidative stress biomarkers, and to clarify the role of mullets for monitoring pollution in River Douro estuary. Mullets chronically exposed to a mixture of contaminants in Douro estuary were captured in Spring of 2001, 2002 and 2003. The activities of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX); and oxidative damages in lipids (lipid peroxidation) and in proteins (protein carbonyl content) were assessed at capture day and after transfer to unpolluted seawater for 1, 4 and 8 months. An overall decrease in the activities of the antioxidant enzymes was detected, except for the GPX after 4 months depuration. CAT activity exhibited the more significant decrease at the end of the long-term depuration. The decrease in SOD activity after 1 month of depuration was then maintained during the remaining depuration period. Regarding oxidative damages, a decrease in lipid peroxidation as well as the content of oxidised proteins was observed during depuration. Indeed, at capture the activities of antioxidant defences were higher as a result of the formation of reactive oxygen species (ROS) from the metabolism of pollutants. The oxidative damaged molecules were repaired or degraded during the depuration period, supporting the use of such damages as indicators of exposure to pro-oxidant pollutants.  相似文献   

5.
环烷酸是高酸原油的主要污染组分,对水生生态系统造成潜在威胁。在不同浓度环烷酸处理下对两种模式淡水微藻——莱茵衣藻(Chlamydomonas reinhardtii)和小球藻(Chlorella vulgaris)进行了96 h的连续培养,研究了环烷酸胁迫对两种淡水微藻种群及生理生化特征的影响,旨在为水生生态系统中环烷酸污染的生态风险预测与规避提供前瞻性的研究资料。研究结果表明,低浓度环烷酸(0.5～4 mg/L)会刺激淡水微藻的种群增长,而高浓度环烷酸(8～16 mg/L)会抑制淡水微藻的种群增长,造成急性毒性损伤。低浓度环烷酸处理下两种微藻叶绿素a含量上升,脂质积累,高浓度环烷酸处理下两种微藻叶绿素a含量下降而多糖含量上升,推测环烷酸剂量可能会影响淡水微藻能量存储方式。两种微藻在环烷酸胁迫下均会受到氧化损伤,造成活性氧(reactive oxygen species,ROS)含量上升,两种微藻抗氧化酶超氧化物歧化酶(superoxide dismutase,SOD)和过氧化氢酶(catalase,CAT)对环烷酸处理具有种属差异;高浓度环烷酸对淡水微藻的急性损伤具有时间效应,毒性随...  相似文献   

6.
阎波  张欣  张轲  陈莉  田丹 《海洋科学》2021,45(1):44-53
采用半静态染毒实验研究了菲和Cd2+单一及复合污染下胁迫9 d和清水释放2 d过程中毛蚶体内活性氧(ROS)、谷胱甘肽(GSH)含量和谷胱甘肽硫转移酶(GST)活性的变化。结果表明,菲和Cd2+单独胁迫能诱导毛蚶体内ROS含量的增加及GSH含量、GST活性的降低,且随染毒浓度的增加,对各指标影响愈明显,存在剂量-效应关系。毛蚶体内GSH和GST的变化趋势具有一致性。菲和Cd2+复合污染对毛蚶体内的氧化胁迫效应整体大于二者单独污染。在清水释放阶段,单一及复合污染胁迫组各指标均能恢复至对照组水平。表明毛蚶体内抗氧化系统适合作为监测海洋多环芳烃和重金属复合污染的生物标志物。  相似文献   

7.
Intertidal blue mussels, Mytilus edulis, experience hypoxia reoxygenation during tidal emersion and resubmersion cycles, and this is often suggested to represent a major stress for the animals, especially for their respiratory tissues, the gills. We exposed mussels to experimental short and prolonged anoxia and subsequent reoxygenation and analyzed the respiratory response in excised gill tissue and the effects of treatment on reactive oxygen species (mainly ROS: superoxide anion, O2·− and hydrogen peroxide, H2O2), formation using live imaging techniques and confocal microscopy. Our aim was to understand if this “natural stress” would indeed produce oxidative damage and whether antioxidant defenses are induced under anoxia, to prevent oxidative damage during reoxygenation. Exposure to declining pO2 in the respiration chamber caused an increase of gill metabolic rate between 21 and 10 kPa, a pO2 range in which whole animal respiration is reported to be oxyregulating. Exposure of the animals to severe anoxia caused an onset of anaerobiosis (succinate accumulation) and shifted high and low critical pc values (pc1: onset of oxyregulation in gills, pc2: switch from oxyregulation to oxyconformity) to higher pO2. Concentrations of both ROS decreased strongly during anoxic exposure of the mussels and increased upon reoxygenation. This ROS burst induced lipid peroxidation in the mantle, but neither were protein carbonyl levels increased (oxidative damage in the protein fraction), nor did the tissue glutathione concentration change in the gills. Further, analysis of apoptosis markers indicated no induction of cell death in the gills. To our knowledge, this is the first paper that directly measures ROS formation during anoxia reoxygenation in mussels. We conclude that hypoxia tolerant intertidal mussels do not suffer major oxidative stress in gill and mantle tissues under these experimental conditions.  相似文献   

8.
Xenobiotic-mediated productions of reactive oxygen species, via enzymemediated redox cycling, have been implicated in a variety of toxicological phenomena including lipid peroxidation, enzyme inactivation and oxidative DNA damage leading to cancer. A comparison was undertaken of two benthic freshwater fish species that appear to differ markedly in their susceptibility to chemical carcinogenesis—the channel catfish (Ictalurus punctatus) and the more cancer-prone brown bullhead (Ameriurus nebulosus)-in terms of basic biochemical characteristics related to oxidative stress. This has included analysis of microsomal redox cycling of model xenobiotics (e.g. menadione) as well as antioxidant and other detoxifying enzymes in hepatic tissue of the two species. In addition, endpoints of oxidative stress, such as altered glutathione status and oxidative DNA damage, were examined. These studies have revealed numerous qualitative and quantitative differences between the two species both in terms of basal enzyme activities and in species response to model prooxidants. For example, bullhead appear to possess a greater capacity for microsomal redox cycling of xenobiotics, but have glutathione-dependent defense systems less able to withstand oxidative challenge. These and other interspecific differences have allowed for an improved understanding of the basic mechanisms which may underly species susceptibility to oxidative stress and critical manifestations such as cancer.  相似文献   

9.
The present study investigated the proposed involvement of contaminant-stimulated reactive oxygen species (ROS) production in disease processes in fish. NAD(P)H-dependent ROS production of subcellular fractions was determined by the iron/EDTA-mediated oxidation of 2-keto-4-methiolbutyric acid. Hepatic cytosolic NADPH-dependent and microsomal NAD(P)H-dependent ROS production were increased 51-160% (P < 0.05) in rainbow trout (Oncorhynchus mykiss) 15 weeks after a single i.p. injection of polychlorobiphenyl (PCB) (100 mg Clophen A50 kg-1 wet wt.). Hepatic microsomal NADH-dependent ROS production was 114% higher in perch (Perca fluviatilis) from PCB-contaminated Lake J?rnsj?n compared to clean Lake V?nern, Sweden. Hepatic mitochondrial NADH-dependent, cytosolic NADH-dependent and microsomal NADPH-dependent ROS production were variously elevated up to 160% in flounder (Platichthys flesus) at various sites along two pollution transects near to the ports of Rotterdam and Amsterdam, Netherlands. Overall the data indicate increased potential for ROS production in liver of fish exposed to field pollution, and support the hypothesis of oxidative stress as a mechanism of contaminant-mediated disease in fish.  相似文献   

10.
以自然种群高程分布为根据, 选择对潮汐浸泡耐性存在一定差异的白骨壤(Avicennia marina)、桐花树(Aegiceras corniculatum)和木榄(Bruguiera gymnorrhiza)为实验树种。对3种红树幼苗进行为期0d、1d、3d、5d、7d、14d的水淹处理, 测定其根部组织的过氧化物酶(peroxidase, POD)活性、超氧化物歧化酶(superoxide dismutase, SOD)活性、抗坏血酸氧化酶(ascorbic acid oxidase, APX)活性和过氧化氢酶(catalase, CAT)活性。水淹处理会导致植物根部组织受低氧胁迫从而破坏活性氧(reactive oxygen species, ROS)生产和消除的平衡, ROS大量累积给植物带来氧化损伤。实验测定与清除ROS有关的酶指标, 结果表明POD活性在1d至14d的水淹周期内随时间呈现上升趋势, 这可能与POD参与活性氧以及乙醇、乳酸等有毒物质的反应有关。CAT、SOD、APX活性均呈现应激上升后下降趋势, 由此推断该系列抗氧化酶在水淹胁迫发生前中期对消除红树植物根部组织大量产生的活性氧具有重要意义。抗氧化酶系在3种红树植物中的表达存在一定差异, 但整体仍呈相似的变化趋势。通过层次聚类法对各项酶活性指标分析后发现, 白骨壤抗氧化酶系的活性模式与木榄和桐花树的存在一定差异, 但没有发现木榄与桐花树抗氧化酶系统表达模式的明显差异。本研究旨在更好地了解红树林对水淹胁迫的生理适应机制, 为红树林生态系统保护与管理提供理论依据。  相似文献   

11.
Jumbo squid (Dosidicus gigas) is a large oceanic squid endemic off the Eastern Tropical Pacific that undertakes diel vertical migrations into mesopelagic oxygen minimum zones. One of the expected physiological effects of such migration is the generation of reactive oxygen species (ROS) at the surface, promoted by the transition between hypoxia and reoxygenation states. The aim of this study was to investigate the energy expenditure rates and the antioxidant stress strategies of juvenile D. gigas under normoxia and hypoxia, namely by quantifying oxygen consumption rates, antioxidant enzyme activities [including superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST)], heat shock protein expression (Hsp70/Hsc70), and lipid peroxidation [malondialdehyde (MDA) levels]. A high significant decrease (68%) in squid’s metabolic rates was observed during hypoxia (p<0.05). This process of metabolic suppression was followed by a significant increase in Hsp70/Hsc70 expression (p<0.05), which may be interpreted as a strategy to prevent post-hypoxic oxidative damage during the squid’s night upwards migration to the surface ocean. On the other hand, in normoxia, the higher SOD and CAT activities seemed to be a strategy to cope with the reoxygenation process, and may constitute an integrated stress response at shallower depths. GST activity and MDA concentrations did not change significantly from normoxia to hypoxia (p>0.05), with the latter indicating no enhancement of lipid peroxidation (i.e. cellular damage) at the warmer and normoxic surface waters. The understanding of such physiological strategies that are linked to oxygen deprivation and reoxygenation phases may provide valuable information about how this species is quickly responding to the impacts of environmental stressors coupled with global climate change.  相似文献   

12.
Nrf2参与水生动物氧化应激调控的研究进展   总被引：1，自引：0，他引：1  
环境变化会诱导机体活性氧(reactive oxygen species, ROS)水平升高,从而产生氧化应激。氧化应激对所有生物的生存、生长、发育和进化都具有深远的影响。核因子E2相关因子2 (nuclear factor erythroid 2 related factor 2, Nrf2)被公认为细胞氧化应激调控的主导者,与伴侣蛋白Kelch样环氧氯丙烷相关蛋白1 (kelch-like ECH-associated protein 1, Keap1)一起控制数百个解毒酶和抗氧化蛋白编码基因的表达。近年来, Nrf2在水生动物中逐渐获得重视,并在一些模式鱼类如斑马鱼、鲤鱼及其他一些鱼类和水生无脊椎动物中得到研究。介绍了Nrf2的结构以及调控机制,回顾了近年来水生动物Nrf2通路参与氧化应激调控所取得的进展。研究表明, Nrf2在水生动物中广泛存在,在非生物(金属、有机污染物、无机盐、药物及微塑料等)、生物(细菌、病毒、有毒藻类)以及生境变化(冰融、盐胁迫)诱导的氧化应激调控中发挥重要作用。Nrf2一经激活入核,在小Maf蛋白的协助下与抗氧化反应元件(antioxidant-responseelement,ARE)结合,启动一系列ARE驱动基因的表达,并和孕烷X受体(pregnane X receptor, Pxr)、丝裂原活化蛋白激酶(mitogen-activated protein kinase, MAPK)以及芳烃受体(arylhydrocarbonreceptor,AhR)等细胞通路协同作用参与一系列生理过程。Nrf2在水生动物响应环境变化过程中发挥重要的细胞保护机制,有望发展成为抗逆育种潜在的基因靶点。  相似文献   

13.
Harmful Algal Blooms caused by the marine ichthyotoxic dinoflagellate Cochlodinium polykrikoides are responsible for mass mortalities of wild and farmed fish worldwide. In this research, we investigated the cytotoxic mechanisms of aqueous extract of C. polykrikoides on isolated Rainbow trout (Oncorhynchus mykiss) liver hepatocytes. Algal extract exposure with isolated trout hepatocytes caused hepatocyte membrane lysis, reactive oxygen species (ROS) formation, glutathione depletion, lysosomal membrane rupture, collapse of mitochondrial membrane potential, ATP depletion and increase in ADP/ATP ratio, cytochrome C release into the hepatocyte cytosol, and activation of caspases cascade. Anti-oxidants, free radical scavengers, mitochondrial permeability transition (MPT) pore sealing agents, microsomal oxidases inhibitors, ATP generators and lysosomotropic agents protected fish hepatocytes against C. polykrikoides. Fish hepatocyte toxicity was also associated with mitochondrial and lysosomal membrane injury. These events caused cytochrome C release from the mitochondrial intra-membrane space into cytosol. The cytochrome C release could trigger activation of caspase-3 and apoptosis.  相似文献   

14.
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15.
Prorocentrum minimum is a common bloomforming photosynthetic dinoflagellate found along the southern coast of Korea. To investigate the adaptive responses of P. minimum to high light stress, we measured growth rate, and generation of reactive oxidative species (ROS), superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) in cultures exposed to normal (NL) and high light levels (HL). The results showed that HL (800 μmol m?2 s?1) inhibited growth of P. minimum, with maximal inhibition after 7–9 days. HL also increased the amount of ROS and MDA, suggesting that HL stress leads to oxidative damage and lipid peroxidation in this species. Under HL, we first detected superoxide on day 4 and H2O2 on day 5. We also detected SOD activity on day 5 and CAT activity on day 6. The level of lipid peroxidation, an indicator of cell death, was high on day 8. Addition of diphenyleneiodonium (DPI), an NAD(P)H inhibitor, decreased the levels of superoxide generation and lipid peroxidation. Our results indicate that the production of ROS which results from HL stress in P. minimum also induces antioxidative enzymes that counteract oxidative damage and allow P. minimum to survive.  相似文献   

16.
Metals are known to influence lipid peroxidation and oxidative status of marine organisms. Hydrothermal vent mussels Bathymodiolus azoricus live in deep-sea environments with anomalous conditions, including high metal concentrations. Although B. azoricus are aerobic organisms they possess abundant methano and thioautotrophic symbiotic bacteria in the gills. The enzymatic defences (superoxide dismutase (SOD), catalase (CAT), total glutathione peroxidase (Total GPx) and selenium-dependent glutathione peroxidase (Se-GPx)) and lipid peroxidation were determined in the gills of B. azoricus exposed to Cd (0.9 microM), Cu (0.4 microM) and Hg (0.1 microM) with different times of exposure. The experiments were performed in pressurized containers at 9+/-1 degrees C and 85 bars. Results show that vent mussels possess antioxidant enzymatic protection in the gills. Cd and Cu had an inhibitory effect in the enzymatic defence system, contrarily to Hg. These enzymatic systems are not completely understood in the B. azoricus, since reactive oxygen species might be produced through other processes than natural redox cycling, due to hydrogen sulphide and oxygen content present. Also the symbiotic bacteria may play an important contribution in the antioxidant protection of the gills.  相似文献   

17.
As a part of an ongoing search for antioxidants frodm marine sources, antioxidant activities of 24 kinds of seaweeds (4 green algae, 8 brown algae, and 12 red algae) were investigated. The seaweeds were extracted by acetone/ dichloromethane and methanol, respectively. The antioxidant properties of both extracts were evaluated using four different activity tests, including degree of occurrence of intracellular reactive oxygen species (ROS), NO, lipid peroxidation, and GSH (glutathione) in mouse macrophage Raw 264.7 cells. The levels of intracellular reactive oxygen species (ROS) and GSH were measured using 2’,7’-dichlorofluorescin diacetate (DCF-DA) and monobromobimane as fluorescence probe, respectively. Moreover, the generation of NO and lipid peroxidation products were determined by each method based on the Griess reaction and TBARS assay. Solvent extracts from seaweeds such asScytosiphon lomentaria, Prionitis cornea, Laruencia okamurae,Callophyllis japonica, Sargassum horneri, Dictyopteris divaricat a,Lomentaria catenata, Corallina confuse, Ishige okamurae, andAhnfeltiopsis flabelliformi exhibited high antioxidant activities in cellular oxidizing systems.  相似文献   

18.
本文以鲈鱼为实验材料，以鲈鱼体内的丙二醛含量为指标研究了在水样中16种多环芳烃组分和外加芘为实验试剂的条件下，鲈鱼体内不同器官、组织的脂质过氧化程度的变化．实验结果表明：（1）在鲈鱼鳃、全血中的丙二醛浓度较高，而肝脏的丙二醛浓度较低。（2）水样中多环芳烃及外加芘的暴露能导致鲈鱼肝的丙二醛浓度升高，这表明多环芳烃以及芘的暴露能引起鲈鱼肝内脂质过氧化程度的提高。（3）水体中多环芳烃及外加芘浓度的变化对鲈鱼肝的丙二醛浓度的影响具有可逆性，且鲈鱼肝的丙二醛浓度与水环境的多环芳烃（包括芘）暴露浓度呈良好的正相关关系。这说明：鲈鱼肝的丙二醛浓度可作为指示水环境的多环芳烃污染程度的指标。由于生物体内的丙二醛浓度受多种因素的影响，在使用丙二醛浓度指标来指示海洋环境的多环芳烃污染时。最好与其他指标配合使用，以更准确地指示海洋环境多环芳烃污染。  相似文献   

19.
An integrate approach will be discussed for investigations on oxidative stress in xenobiotic toxicity. While the analysis of individual antioxidants is useful for their sensitivity and to understand the mode of action of a stressor, the integration with the analysis of the total antioxidant capacity provides a more holistic assessment of the overall biological significance of such variations. TOSC has a greater predictive value on the health condition of the organisms and allows to discriminate the different role of specific ROS in oxidative stress syndrome.  相似文献   

20.
Cellular and humoral immune parameters are often used as biomarkers to trace environmental and physiological stresses in marine bivalves. In this study, we compared various immune parameters of Manila clams (Ruditapes philippinarum) under normal conditions and under a high level of desiccation, using flow cytometry. The immune parameters analyzed included, total hemocyte count, hemocyte mortality, hemocyte DNA damage, reactive oxygen species (ROS) production, and phagocytosis activity. Total hemocyte count, hemocyte DNA damage, and hemocyte mortality were significantly elevated among clams under high desiccation stress, while phagocytosis activity and spontaneous ROS production were significantly lower compared to those parameters of the control clams (p<0.05). These data suggest that the immune parameters analyzed in this study well reflect the physiological status of clams.  相似文献   

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