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Jia R, Quan D, Min X, Nie X, Huang X, Ge J, Ren Q. Glutathione S-transferase gene diversity and their regulation by Nrf2 in Chinese mitten crab (Eriocheir sinensis) during nitrite stress. Gene 2023; 864:147324. [PMID: 36863531 DOI: 10.1016/j.gene.2023.147324] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/14/2023] [Accepted: 02/23/2023] [Indexed: 03/02/2023]
Abstract
Eriocheir sinensis is one of the most important economic aquatic products in China. However, nitrite pollution has become a serious threat to the healthy culture of E. sinensis. Glutathione S-transferase (GST) is an important phase II detoxification enzyme, which plays a leading role in the cellular detoxification of exogenous substances. In this study, we obtained 15 GST genes (designated as EsGST1-15) from E. sinensis, and their expression and regulation in E. sinensis under nitrite stress were studied. EsGST1-15 belonged to different GST subclasses. EsGST1, EsGST2, EsGST3, EsGST4, and EsGST5 belonged to Delta-class GSTs; EsGST6 and EsGST7 are Theta-class GSTs; EsGST8 is a mGST-3-class GST; EsGST9 belonged to mGST-1-class GSTs; EsGST10 and EsGST11 belonged to Sigma-class GSTs; EsGST12, EsGST13, and EsGST14 are Mu-class GSTs; EsGST15 is a Kappa-class GST. Tissue distribution experiments showed that EsGSTs were widely distributed in all detected tissues. The expression level of EsGST1-15 was significantly increased in the hepatopancreas under nitrite stress, indicating that EsGSTs were involved in the detoxification of E. sinensis under nitrite stress. Nuclear factor-erythroid 2 related factor 2 (Nrf2) is a transcription factor that can activate the expression of detoxification enzyme. We detected the expression of EsGST1-15 after interfering with EsNrf2 in the hepatopancreas of E. sinensis with or without nitrite stress. Results showed that EsGST1-15 were all regulated by EsNrf2 with or without nitrite stress. Our study provides new information about the diversity, expression, and regulation of GSTs in E. sinensis under nitrite stress.
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Affiliation(s)
- Rui Jia
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province 210023, China
| | - Derun Quan
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province 210023, China
| | - Xiuwen Min
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province 210023, China
| | - Ximei Nie
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province 210023, China
| | - Xin Huang
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province 210023, China.
| | - Jiachun Ge
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, Jiangsu Province 210017, China.
| | - Qian Ren
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, Jiangsu Province 210044, China.
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Sifi K, Soltani N. Seasonal changes of two biomarkers of oxidative stress (LDH, MDA) in the edible mollusc Donax trunculus (Mollusca: Bivalvia) from the Gulf of Annaba (Algeria): correlation with carbohydrate and lipid contents. MOLLUSCAN RESEARCH 2018. [DOI: 10.1080/13235818.2018.1499389] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Karima Sifi
- Laboratory of Applied Animal Biology, Faculty of Sciences, Department of Biology, University Badji Mokhtar of Annaba, Annaba, Algeria
| | - Noureddine Soltani
- Laboratory of Applied Animal Biology, Faculty of Sciences, Department of Biology, University Badji Mokhtar of Annaba, Annaba, Algeria
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Bownik A. Harmful algae: Effects of cyanobacterial cyclic peptides on aquatic invertebrates-a short review. Toxicon 2016; 124:S0041-0101(16)30319-1. [PMID: 27984061 DOI: 10.1016/j.toxicon.2016.10.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 10/24/2016] [Accepted: 10/27/2016] [Indexed: 12/22/2022]
Abstract
Cyanotoxins are secondary metabolites produced by cyanobacteria. Cyclic peptides, microcystins and nodularin commonly detected in water reservoirs of different parts of the world may induce various detrimental effects in a wide range of organisms from bacteria to humans. This paper presents the current state of knowledge on the effects of microcystins and nodularin on aquatic invertebrates: zooplankton, decapods and mollusks. Accumulation of microcystins and nodularin in these organisms and possible transfer of the cyanotoxins through the food web and possible threat to humans as consumers are also discussed.
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Affiliation(s)
- Adam Bownik
- Department of Biological Basis of Animal Production, University of Life Sciences, Akademicka 13 Str., 20-950 Lublin, Poland.
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Yuan J, Gu Z, Zheng Y, Zhang Y, Gao J, Chen S, Wang Z. Accumulation and detoxification dynamics of microcystin-LR and antioxidant responses in male red swamp crayfish Procambarus clarkii. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 177:8-18. [PMID: 27218425 DOI: 10.1016/j.aquatox.2016.05.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Revised: 04/30/2016] [Accepted: 05/06/2016] [Indexed: 06/05/2023]
Abstract
MC-LR is one of major microcystin isoforms with potent hepatotoxicity. In the present study, we aim to: 1) explore the dynamics of MC-LR accumulation and elimination in different tissues of male red swamp crayfish Procambarus clarkii; 2) reveal the mechanisms underlying hepatic antioxidation and detoxification. In the semi-static toxicity tests under the water temperature of 25±2°C, P. clarkii were exposed to 0.1, 1, 10 and 100μg/L MC-LR for 7days for accumulation and subsequently relocated to freshwater for another 7days to depurate MC-LR. MC-LR was measured in the hepatopancreas, intestine, abdominal muscle and gill by HPLC. The enzyme activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST), content of glutathione (GSH), and transcripts of Mn-sod, cat, gpx1, Mu-gst, heat shock protein90 (hsp90), hsp70 and hsp60 in hepatopancreas were detected. The results showed that P. clarkii accumulated more MC-LR in intestine, and less in abdominal muscle and gill during accumulation period and eliminated the toxin more quickly in gill and abdominal muscle, and comparatively slowly in intestine during depuration period. The fast increase of SOD and CAT activities at early stage, subsequent decrease at later stage of accumulation period and then fast increase during depuration period were partially consistent with the transcriptional changes of their respective genes. GPx was activated by longer MC-LR exposure and gpx1 mRNA expression showed uncoordinated regulation pattern compared with its enzyme. Hsp genes were up-regulated when P. clarkii was exposed to MC-LR.
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Affiliation(s)
- Julin Yuan
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China; Zhejiang Institute of Freshwater Fisheries, Freshwater Fishery Healthy Breeding Laboratory of Ministry of Agriculture, Huzhou, Zhejiang 313001, China
| | - Zhimin Gu
- Zhejiang Institute of Freshwater Fisheries, Freshwater Fishery Healthy Breeding Laboratory of Ministry of Agriculture, Huzhou, Zhejiang 313001, China.
| | - Yao Zheng
- Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences; Scientific Observing and Experimental Station of Fishery Resources and Environment in the Lower Reaches of the Changjiang River, Wuxi 214081, China
| | - Yingying Zhang
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China
| | - Jiancao Gao
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China
| | - Shu Chen
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China
| | - Zaizhao Wang
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China.
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Sabatini SE, Brena BM, Pirez M, de Molina MDCR, Luquet CM. Oxidative effects and toxin bioaccumulation after dietary microcystin intoxication in the hepatopancreas of the crab Neohelice (Chasmagnathus) granulata. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2015; 120:136-141. [PMID: 26070043 DOI: 10.1016/j.ecoenv.2015.05.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 05/22/2015] [Accepted: 05/26/2015] [Indexed: 06/04/2023]
Abstract
We studied the accumulation and depuration of microcystin-LR (MCLR) in the hepatopancreas of the crab Neohelice granulata fed twice weekly with either non toxic or MCLR-producing Microcystis aeruginosa (strain NPDC1 or NPJB, respectively) during seven weeks. We also analyzed MCLR effects on the oxidative stress- and detoxification-related variables, superoxide dismutase and glutathione-S-transferase activities, and the levels of reduced glutathione and lipid peroxidation (as thiobarbituric acid reactive substances, TBARS). Hepatopancreas MCLR content slightly increased during the first three weeks, up to 8.81±1.84ngg(-1) wet tissue mass (WTM) and then started to decrease to a minimum of 1.57±0.74ngg(-1) WTM at the seventh week (p<0.05 with respect to that in the first week). TBARS levels were about 55% higher in treated than in control N. granulata (p<0.001 and p<0.05) during the first three weeks of the experimental period. GSH content became 50% lower than in control individuals (p<0.01) during weeks 6 and 7. SOD activity was increased by about 2-fold (p<0.05 or p<0.001) from week 3 to 7 in treated crabs with respect to control ones, while GST activity was about 70% higher in treated than in control crabs from week 4 to week 7 (p<0.05). Our data suggest that in the hepatopancreas of N. granulata MCLR accumulation and oxidative damage are limited and reversed by detoxification-excretion and antioxidant mechanisms. The activation of these defensive mechanisms becomes evident at 3-4 weeks after the start of the intoxication.
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Affiliation(s)
- Sebastián E Sabatini
- IQUIBICEN-Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 2° Pabellón, 4° piso, Ciudad Universitaria, (CP 1428) Buenos Aires, Argentina; Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 2° Pabellón, 4° piso, Ciudad Universitaria, (1428) Buenos Aires, Argentina.
| | - Beatríz M Brena
- Departamento de Biociencias, Cátedras de Bioquímica, Facultad de Química, Universidad de la República, Montevideo, Uruguay.
| | - Macarena Pirez
- Departamento de Biociencias, Cátedras de Bioquímica, Facultad de Química, Universidad de la República, Montevideo, Uruguay.
| | - María Del Carmen Ríos de Molina
- IQUIBICEN-Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 2° Pabellón, 4° piso, Ciudad Universitaria, (CP 1428) Buenos Aires, Argentina.
| | - Carlos M Luquet
- LEA, INIBIOMA-CONICET-Universidad Nacional del Comahue, CEAN, Junín de los Andes, Argentina.
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Wood JD, Franklin RB, Garman G, McIninch S, Porter AJ, Bukaveckas PA. Exposure to the cyanotoxin microcystin arising from interspecific differences in feeding habits among fish and shellfish in the James River Estuary, Virginia. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:5194-5202. [PMID: 24694322 DOI: 10.1021/es403491k] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The cyanotoxin, microcystin (MC), is known to accumulate in the tissues of diverse aquatic biota although factors influencing exposure, such as feeding habits and seasonal patterns in toxin production, are poorly known. We analyzed seasonal variation in the MC content of primary and secondary consumers, and used dietary analysis (gut contents and stable isotopes) to improve understanding of cyanotoxin transport in food webs. Periods of elevated toxin concentration were associated with peaks in the abundance of genes specific to Microcystis and MC toxin production (mcyD). Peak toxin levels in consumer tissues coincided with peak MC concentrations in seston. However, toxins in tissues persisted in overwintering populations suggesting that potential health impacts may not be limited to bloom periods. Interspecific differences in tissue MC concentrations were related to feeding habits and organic matter sources as pelagic fishes ingested a greater proportion of algae in their diet, which resulted in greater MC content in liver and muscle tissues. Sediments contained a greater proportion of allochthonous (terrestrial) organic matter and lower concentrations of MC, resulting in lower toxin concentrations among benthic detritivores. Among shellfish, the benthic suspension feeder Rangia cuneata (wedge clam) showed seasonal avoidance of toxin ingestion due to low feeding rates during periods of elevated MC. Among predators, adult Blue Catfish had low MC concentrations, whereas Blue Crabs exhibited high levels of MC in both muscle and viscera.
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Affiliation(s)
- Joseph D Wood
- Department of Biology and Center for Environmental Studies Virginia Commonwealth University , Richmond, Virginia 23284, United States
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Meneely JP, Elliott CT. Microcystins: measuring human exposure and the impact on human health. Biomarkers 2013; 18:639-49. [DOI: 10.3109/1354750x.2013.841756] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Gonçalves-Soares D, Zanette J, Yunes JS, Yepiz-Plascencia GM, Bainy ACD. Expression and activity of glutathione S-transferases and catalase in the shrimp Litopenaeus vannamei inoculated with a toxic Microcystis aeruginosa strain. MARINE ENVIRONMENTAL RESEARCH 2012; 75:54-61. [PMID: 21889198 DOI: 10.1016/j.marenvres.2011.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 07/23/2011] [Accepted: 07/27/2011] [Indexed: 05/21/2023]
Abstract
Microcystin (MC) produced during cyanobacteria blooms is notably toxic to human and wildlife. Conjugation with reduced glutathione (GSH) by glutathione S-transferase (GST) and the antioxidant enzymes defenses (e.g. catalase, CAT) are important biochemical defense mechanisms against MCs toxicity. We investigated the enzymatic activity of CAT and GST and the gene expression levels of CAT and eight GST isoforms in the hepatopancreas of the globally farmed shrimp Litopenaeus vannamei 48-h after injection with a sub-lethal dose of 100 μg kg⁻¹ of a toxic Microcystis aeruginosa extract. MCs caused up-regulation for GSTΩ, μ and a MAPEG isoform, by 12-, 2.8- and 1.8-fold, respectively, and increases in the total GST enzyme activity and CAT enzyme activity. The study points to the importance of further characterization for the L. vannamei GST isoforms and GST/CAT post-translational regulation processes to better understand the key mechanisms involved in the shrimp's defense against MC exposure.
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Affiliation(s)
- Daniela Gonçalves-Soares
- Departamento de Bioquímica, Núcleo de Estudos em Patologia Aquícola, Universidade Federal de Santa Catarina, Servidão Caminho do Porto, s/n, Itacorubi, Florianópolis, SC 88034-257, Brazil
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Ferrão-Filho ADS, Kozlowsky-Suzuki B. Cyanotoxins: bioaccumulation and effects on aquatic animals. Mar Drugs 2011; 9:2729-2772. [PMID: 22363248 PMCID: PMC3280578 DOI: 10.3390/md9122729] [Citation(s) in RCA: 194] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 11/29/2011] [Accepted: 12/01/2011] [Indexed: 12/21/2022] Open
Abstract
Cyanobacteria are photosynthetic prokaryotes with wide geographic distribution that can produce secondary metabolites named cyanotoxins. These toxins can be classified into three main types according to their mechanism of action in vertebrates: hepatotoxins, dermatotoxins and neurotoxins. Many studies on the effects of cyanobacteria and their toxins over a wide range of aquatic organisms, including invertebrates and vertebrates, have reported acute effects (e.g., reduction in survivorship, feeding inhibition, paralysis), chronic effects (e.g., reduction in growth and fecundity), biochemical alterations (e.g., activity of phosphatases, GST, AChE, proteases), and behavioral alterations. Research has also focused on the potential for bioaccumulation and transferring of these toxins through the food chain. Although the herbivorous zooplankton is hypothesized as the main target of cyanotoxins, there is not unquestionable evidence of the deleterious effects of cyanobacteria and their toxins on these organisms. Also, the low toxin burden in secondary consumers points towards biodilution of microcystins in the food web as the predominant process. In this broad review we discuss important issues on bioaccumulation and the effects of cyanotoxins, with emphasis on microcystins, as well as drawbacks and future needs in this field of research.
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Affiliation(s)
- Aloysio da S. Ferrão-Filho
- Laboratory of Evaluation and Promotion of Environmental Health, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365, Manguinhos, Rio de Janeiro, RJ 21045-900, Brazil
| | - Betina Kozlowsky-Suzuki
- Departament of Ecology and Marine Resources, Federal University of Rio de Janeiro State (UNIRIO), Av. Pasteur 458, Urca, Rio de Janeiro, RJ 22290-040, Brazil;
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Amado LL, Monserrat JM. Oxidative stress generation by microcystins in aquatic animals: why and how. ENVIRONMENT INTERNATIONAL 2010; 36:226-235. [PMID: 19962762 DOI: 10.1016/j.envint.2009.10.010] [Citation(s) in RCA: 203] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 09/09/2009] [Accepted: 10/27/2009] [Indexed: 05/28/2023]
Abstract
Microcystins (MICs) are potent toxins produced worldwide by cyanobacteria during bloom events. Phosphatases inhibition is a well recognized effect of this kind of toxins as well as oxidative stress. However, it is not fully understood why and how MICs exposure can lead to an excessive formation of reactive oxygen species (ROS) that culminate in oxidative damage. Some evidences suggest a close connection between cellular hyperphosphorylation state and oxidative stress generation induced by MICs exposure. It is shown, based on literature data, that MICs incorporation per se can be the first event that triggers glutathione depletion and the consequent increase in ROS concentration. Also, literature data suggest that hyperphosphorylated cellular environment induced by MICs exposure can modulate antioxidant enzymes, contributing to the generation of oxidative damage. This review summarizes information on MICs toxicity in aquatic animals, focusing on mechanistic aspects, and rise questions that in our opinion needs to be further investigated.
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Affiliation(s)
- L L Amado
- Curso de Pós-graduação em Ciências Fisiológicas - Fisiologia Animal Comparada, Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brazil
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Martins JC, Vasconcelos VM. Microcystin dynamics in aquatic organisms. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2009; 12:65-82. [PMID: 19117210 DOI: 10.1080/10937400802545151] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Eutrophication of surface water has increased significantly during the past decade, resulting in increased occurrences of toxic blooms. Cyanotoxins have become a global health threat to humans, wild animals, or domestic livestock. Hepatotoxic microcystins (MC) are the predominant cyanotoxins, which accumulate in aquatic organisms and are transferred to higher trophic levels. This is an issue of major concern in aquatic toxicology, as it involves the risk for human exposure through the consumption of contaminated fish and other aquatic organisms. The persistence and detoxification of MC in aquatic organisms are important issues for public health and fishery economics. Bioaccumulation of MC depends on the toxicity of the strains, mode of feeding, and detoxication mechanisms. Although mussels, as sessile filter feeders, seem to be organisms that ingest more MC, other molluscs like gastropods, as well as zooplankton and fish, may also retain average similar levels of toxins. Edible animals such as some species of molluscs, crustaceans, and fish present different risk because toxins accumulate in muscle at low levels. Carnivorous fish seem to accumulate high MC concentrations compared to phytophagous or omnivorous fish. This review summarizes the existing data on the distribution and dynamics of MC in contaminated aquatic organisms.
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Affiliation(s)
- José C Martins
- Departamento de Zoologia e Antropologia, Faculdade de Ciencias, Universidade do Porto, Centro Interdisciplinar de Investigacao Marinha e Ambiental, CIIMAR/CIMAR, Porto, Portugal
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Leão JC, Geracitano LA, Monserrat JM, Amado LL, Yunes JS. Microcystin-induced oxidative stress in Laeonereis acuta (Polychaeta, Nereididae). MARINE ENVIRONMENTAL RESEARCH 2008; 66:92-94. [PMID: 18533247 DOI: 10.1016/j.marenvres.2008.02.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Oxidative stress induced by microcystins was evaluated in an estuarine worm, Laeonereis acuta (Nereididae). Ten organisms were exposed to lyophilized cells of a toxic Microcystisaeruginosa strain RST9501 ( approximately 2 microg/mL microcystins, MC); 10 were exposed to lyophilized cells of a nontoxic Aphanotece sp. strain RSMan92 and 10 were maintained without cyanobacterial cells. Exposure time was 48 h. The enzymatic antioxidant defenses, as well as the oxidative damage, were analyzed. Toxic and nontoxic cyanobacteria lowered catalase activity with no changes in glutathione reductase and glutathione-S-transferase activities. This may have led to toxin intracellular accumulation, which should favor oxidative stress generation, observed by the high lipid peroxide and DNA-protein crosslink levels in the group exposed to MC.
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Affiliation(s)
- J C Leão
- Unidade de Pesquisa em Cianobactérias, Fundação Universidade Federal do Rio Grande, Pós-Graduação em Oceanografia Biológica, Rio Grande/RS, Brazil
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