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Moraes ACND, Fallah HP, de Magalhães VF, Habibi HR. Cylindrospermopsin induces oocyte maturation and disrupts gene expression in zebrafish ovarian follicles. Environ Toxicol Pharmacol 2022; 94:103915. [PMID: 35750255 DOI: 10.1016/j.etap.2022.103915] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/23/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
There is evidence that cylindrospermopsin (CYN) exerts reproductive toxicity in mice. However, little information is available concerning the toxicity of CYN in nonmammalian vertebrates. Here, we investigated the direct action of CYN on female reproduction by studying germinal vesicle breakdown, transcript abundance, caspase-3 activity, and testosterone production using cultured follicle-enclosed zebrafish oocytes as a model system. Treatment of follicles with 1,000 μg/L CYN significantly increased GVBD, Caspase-3 activity, and hCG-induced testosterone secretion. Exposure to CYN also reduced the abundance of 3βhsd as well as hCG-induced fshr and era transcripts and increased cyp19a1 mRNA levels. In summary, this study provides a framework for a better understanding of the adverse action of CYN on female reproduction in zebrafish and other vertebrate species. The findings are also relevant to developing valid biomarkers for CYN by measuring zebrafish oocyte maturation and gene expression.
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Affiliation(s)
- Adriana Carvalho Natal de Moraes
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21.941-902, Brazil; Department of Biological Science, University of Calgary, Calgary, AB T2N 1N4, Canada.
| | | | - Valéria Freitas de Magalhães
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21.941-902, Brazil
| | - Hamid R Habibi
- Department of Biological Science, University of Calgary, Calgary, AB T2N 1N4, Canada
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de Moraes ACN, Caires FO, Imperio GE, Nóbrega RH, Ortiga-Carvalho TM, de Magalhães VF. Cylindrospermopsin Disrupts Estrous Cycle and Increases Spermatogenesis in Mice. Reprod Sci 2022; 29:2876-2884. [PMID: 35257354 DOI: 10.1007/s43032-022-00907-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/27/2022] [Indexed: 11/29/2022]
Abstract
Cylindrospermopsin (CYN) is a water-soluble cyanotoxin that has been linked to several cases of poisoning in the world. In vitro studies have shown that CYN acts as an endocrine disruptor by inhibiting progesterone synthesis in primary cell cultures of women, showing estrogenic activity. However, in vivo assessment of CYN in the female and male reproductive systems remains unknown. We thus aimed to evaluate the in vivo effects of CYN in both the female and male reproductive systems of mice. A single intraperitoneal exposure to 64 µg of CYN/kg body weight was performed in females. Estrous cycle was evaluated daily by vaginal cytology, and serum progesterone and estradiol levels were measured after 50 days. We showed an impairment in the estrous cycle as well as a decrease in circulating plasma progesterone levels. In males, weekly intraperitoneal doses of 20 μg of CYN/kg body weight were given and groups were killed after one, two, or four doses. CYN increased the testosterone levels in the groups that received one or two doses of CYN. Additionally, CYN induced a transient increase in spermatozoa in males after four doses. Our results highlight that CYN interferes with both male and female reproductive systems and may lead to infertility. As far as we know, this is the first report showing the impacts of CYN on the mammalian reproductive system, suggesting a threat from this cyanotoxin to human and environmental health.
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Affiliation(s)
- Adriana Carvalho Natal de Moraes
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Institute of Biophysics Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, 21941-902, Brazil.
| | - Fernanda Oliveira Caires
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Institute of Biophysics Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, 21941-902, Brazil
| | - Guinever Eustaquio Imperio
- Laboratory of Translational Endocrinology, Institute of Biophysics Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, 21941-902, Brazil
| | - Rafael Henrique Nóbrega
- Reproductive and Molecular Biology Group, Department of Structural and Functional Biology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, 18618-970, Brazil
| | - Tania Maria Ortiga-Carvalho
- Laboratory of Translational Endocrinology, Institute of Biophysics Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, 21941-902, Brazil
| | - Valéria Freitas de Magalhães
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Institute of Biophysics Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, 21941-902, Brazil
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Calado SLDM, Santos GS, Vicentini M, Bozza DC, Prodocimo V, Magalhães VFD, Cestari MM, Silva de Assis HC. Multiple biomarkers response in a Neotropical fish exposed to paralytic shellfish toxins (PSTs). Chemosphere 2020; 238:124616. [PMID: 31466003 DOI: 10.1016/j.chemosphere.2019.124616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/16/2019] [Accepted: 08/17/2019] [Indexed: 06/10/2023]
Abstract
The Alagados Reservoir (Southern Brazil) is used as water supply, and since 2002 there have been reports with a presence of cyanobacterial blooms and cyanotoxins. In order to assess the water quality and the ecological integrity of the reservoir, we evaluated biochemical, genotoxic and osmoregulatory biomarkers in the freshwater cichlid fish (Geophagus brasiliensis) that were exposed to PSTs. The fish were sampled in the Alagados Reservoir in February 2016 (Summer) and were divided in three groups: 1) Reservoir group (RES): fish were collected immediately after sampling; 2) Depuration group (DEP): fish were submitted to the depuration experiment for 90 days in the laboratory; and 3) Reproduction group (REP): fish were kept in the laboratory until the fertilization and the chemical analyses were performed on the offspring (F1 generation). In the RES and DEP the blood, brain, muscle, liver and gills were collected for biochemical, genotoxic and osmoregulatory biomarkers analysis. Our results showed that the fish from the Alagados Reservoir (RES) presented oxidative stress and DNA damage; and after 90 days (DEP), the antioxidant system and DNA damage were recovered. Although PSTs were considered a risk to the ecological integrity of this water body; PSTs concentrations were not found in the tissues of the F1 generation. In addition, the biomarkers used were useful tools to evaluate the effects of environment contamination. Therefore, it is necessary to develop new technologies and monitoring programs in order to reduce cyanobaterial blooms, cyanotoxins and human activities that cause the contamination in aquatic environments.
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Affiliation(s)
- Sabrina Loise de Morais Calado
- Ecology and Conservation Program Post-Graduation, Federal University of Paraná, Avenue Coronel Francisco Heráclito dos Santos, 100, Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil
| | - Gustavo Souza Santos
- Department of Genetics, Federal University of Paraná, Avenue Coronel Francisco Heráclito dos Santos, 100, Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil
| | - Maiara Vicentini
- Ecology and Conservation Program Post-Graduation, Federal University of Paraná, Avenue Coronel Francisco Heráclito dos Santos, 100, Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil
| | - Deivyson Cattine Bozza
- Department of Physiology, Federal University of Paraná, Avenue Coronel Francisco Heráclito dos Santos, 100, Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil
| | - Viviane Prodocimo
- Department of Physiology, Federal University of Paraná, Avenue Coronel Francisco Heráclito dos Santos, 100, Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil
| | - Valéria Freitas de Magalhães
- Institute of Biophysics Carlos Chagas Filho, Avenue Carlos Chagas Filho, 373 Bloco G, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil
| | - Marta Margarete Cestari
- Department of Genetics, Federal University of Paraná, Avenue Coronel Francisco Heráclito dos Santos, 100, Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil
| | - Helena Cristina Silva de Assis
- Department of Pharmacology, Federal University of Paraná, Avenue Coronel Francisco Heráclito dos Santos, 100, Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil.
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Calado SLDM, Santos GS, Wojciechowski J, Magalhães VFD, Silva de Assis HC. The accumulation dynamics, elimination and risk assessment of paralytic shellfish toxins in fish from a water supply reservoir. Sci Total Environ 2019; 651:3222-3229. [PMID: 30463170 DOI: 10.1016/j.scitotenv.2018.10.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 09/27/2018] [Accepted: 10/03/2018] [Indexed: 06/09/2023]
Abstract
Paralytic shellfish Toxins (PSTs) or saxitoxins are neurotoxins that block the neural transmission by binding to the voltage-gated sodium channels in the nerve cells. There are >50 analogues described, which could be biotransformed into a molecular form of greater or lesser toxicity. The Alagados Reservoir is used for water supply, and persistent cyanobacterial blooms as well as PSTs concentrations have been found in this water body since 2002. The aims of this study were to quantify the concentrations of PSTs in the water and fish samples from the Alagados Reservoir. In addition, we evaluated the elimination of PSTs for 90 days in fish and estimated the potential risk to human health. Water and fish samples were collected from the reservoir. For the water samples the phytoplankton and chemical analyses were carried out. Fish were divided into two sample times: Field Samples (FS) and Elimination Experiment Samples (EES), which were maintained for 90 days in filtered and dechlorinated water. For chemical analysis, the muscles of FS were collected on the fish sampling day and the muscles and feces of EES were collected at 7, 15, 30, 45, 60, 75 and 90 days. PSTs concentrations were present in water and fish samples, and they were estimated as a potential risk to humans; mainly for children. In addition, toxins were accumulated, biotransformed to other analogues and excreted by the fish. However, after 90 days, the toxins were still present in the water and fish muscle. Therefore, PSTs can remain for a long period in water, and fish can be a carrier of these neurotoxins. New approaches of monitoring and management are necessary in the actual global context of cyanobacteria and cyanotoxins.
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Affiliation(s)
- Sabrina Loise de Morais Calado
- Ecology and Conservation Program Post-Graduation - Federal University of Paraná (UFPR), Box 19031, 81530-980 Curitiba, PR, Brazil.
| | - Gustavo Souza Santos
- Ecology and Conservation Program Post-Graduation - Federal University of Paraná (UFPR), Box 19031, 81530-980 Curitiba, PR, Brazil.
| | - Juliana Wojciechowski
- Ecology and Conservation Program Post-Graduation - Federal University of Paraná (UFPR), Box 19031, 81530-980 Curitiba, PR, Brazil.
| | - Valéria Freitas de Magalhães
- Institute of Biophysics Carlos Chagas Filho, Box 21941-902, Ilha do Fundão, Rio de Janeiro, Rio de Janeiro, Brazil.
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Calado SLDM, Santos GS, Leite TPB, Wojciechowski J, Nadaline M, Bozza DC, Magalhães VFD, Cestari MM, Prodocimo V, Silva de Assis HC. Depuration time and sublethal effects of microcystins in a freshwater fish from water supply reservoir. Chemosphere 2018; 210:805-815. [PMID: 30041158 DOI: 10.1016/j.chemosphere.2018.07.075] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 07/13/2018] [Accepted: 07/14/2018] [Indexed: 06/08/2023]
Abstract
Microcystins (MCs) are hepatotoxins that have been considered to be a worldwide problem due the effects that they can cause to environmental and human health systems. The Iraí Reservoir, located in the South of Brazil, is used as a water supply and MCs concentrations have been reported in this ecosystem. This study aimed to determine the MCs concentrations in the Iraí Reservoir and to evaluate the MCs depuration time and the health of Geophagus brasiliensis using biomarkers. Water and fish samples were collected in the Iraí Reservoir from August 2015 to May 2016. Phytoplankton and chemical analyses were conducted using water samples and the fish were divided into two groups; the Immediate Group (IMM) and the Depuration Group (DEP). In the IMM group, the blood, liver, muscle, brain and gills were collected, in order to evaluate the genotoxic, biochemical and chemical biomarkers. The DEP group was used in the depuration experiment for 90 days, and after this period the fish were submitted to the same procedure as the IMM group. Our results suggested that fish accumulated MCs and it may have caused oxidative stress, neurotoxicity and molecular damage. Furthermore, MCs concentrations increased during the depuration time and it resulted in molecular damage over the first 30 days. After 90 days, the recovery of the antioxidant system occurred. The depuration started on the 15th day, however, the toxins were still present in the samples. Therefore, the effects and the persistence of MCs are a risk to environmental systems and human health.
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Affiliation(s)
- Sabrina Loise de Morais Calado
- Ecology and Conservation Program Post-Graduation, Federal University of Paraná, Box 19031, 81530-990, Curitiba-PR, Brazil.
| | - Gustavo Souza Santos
- Department of Genetics, Federal University of Paraná, Box 19031, 81530-990, Curitiba-PR, Brazil.
| | - Talitha Pires Borges Leite
- Department of Pharmacology, Federal University of Paraná (UFPR), Box 19031, 81530-990, Curitiba-PR, Brazil.
| | - Juliana Wojciechowski
- Ecology and Conservation Program Post-Graduation, Federal University of Paraná, Box 19031, 81530-990, Curitiba-PR, Brazil.
| | - Mário Nadaline
- Department of Genetics, Federal University of Paraná, Box 19031, 81530-990, Curitiba-PR, Brazil.
| | - Deivyson Cattine Bozza
- Department of Physiology, Federal University of Paraná, Box 19031, 81530-990, Curitiba-PR, Brazil.
| | | | - Marta Margarete Cestari
- Department of Genetics, Federal University of Paraná, Box 19031, 81530-990, Curitiba-PR, Brazil.
| | - Viviane Prodocimo
- Department of Physiology, Federal University of Paraná, Box 19031, 81530-990, Curitiba-PR, Brazil.
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da Silva RDC, Grötzner SR, Moura Costa DD, Garcia JRE, Muelbert J, de Magalhães VF, Filipak Neto F, de Oliveira Ribeiro CA. Comparative bioaccumulation and effects of purified and cellular extract of cylindrospermopsin to freshwater fish Hoplias malabaricus. J Toxicol Environ Health A 2018; 81:620-632. [PMID: 29764335 DOI: 10.1080/15287394.2018.1469101] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 04/19/2018] [Accepted: 04/22/2018] [Indexed: 06/08/2023]
Abstract
Many tropical freshwater ecosystems are impacted by cyanobacteria blooms increasing the risk of cyanotoxins exposure to aquatic organisms while human populations may be exposed by eating fish, drinking water, or dermal swimming. However, few toxicological data are available on the influence of cyanobacteria blooms in particular, cylindrospermopsin (CYN) on Brazilian neotropical fish. A number of studies demonstrated the ability of CYN to bioaccumulate in freshwater organisms and consequently enter the human food chain. The aim of the current study was to examine the effects of CYN following single intraperitoneal injection (50 µg/kg) of purified CYN (CYNp) or aqueous extract of CYN-producing cyanobacteria extract (CYNex) after 7 or 14 days. Biomarkers such as histopathology (liver), oxidative stress (liver and brain), and acetylcholinesterase (AChE) activity (muscle and brain) were utilized in order to assess the influence of CYN on Hoplias malabaricus. In terms of AChE activity, administration of CYNex and CYNp both muscle and brains were used as target tissues. In brain an increase of glutathione S-transferase (GST) activity and lipid peroxidation (LPO) levels was noted suggesting an imbalance in redox cycling. The majority of biomarkers did not present significant alterations in liver, but an elevation in superoxide dismutase (SOD) and glucose 6 phosphate dehydrogenase (G6PDH) activities was found. Different profiles of GST activity were observed in both studied groups (CYNex and CYNp) while LPO (CYNex and CYNp) and protein carbonylation (PCO) (CYNp) levels increased after exposure to CYN. The incidence of necrosis, melanomacrophages centers, and free melanomacrophages were detected as evidence of cell death and immune responses. Nonprotein thiols (NPT) levels were not markedly affected in both exposed groups. Data demonstrated that in vivo exposure to CYN produced biochemical and morphological disturbances in liver and brain of H. malabaricus.
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Affiliation(s)
- Rodrigo de Cássio da Silva
- a Departamento de Biologia Estrutural, Molecular e Genética , Universidade Estadual de Ponta Grossa , Ponta Grossa , Brasil
| | - Sonia Regina Grötzner
- b Departamento de Biologia Celular , Universidade Federal do Paraná, Cx , Curitiba , Brasil
| | | | | | - Juan Muelbert
- c Estação de Piscicultura Panamá , Paulo Lopes , Brazil
| | - Valéria Freitas de Magalhães
- d Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Bloco G, Ilha do Fundão , Universidade Federal do Rio de Janeiro , Rio de Janeiro , Brazil
| | - Francisco Filipak Neto
- b Departamento de Biologia Celular , Universidade Federal do Paraná, Cx , Curitiba , Brasil
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da S Ferrão-Filho A, de Abreu S Silva D, de Oliveira TA, de Magalhães VF, Pflugmacher S, da Silva EM. Single and combined effects of microcystin- and saxitoxin-producing cyanobacteria on the fitness and antioxidant defenses of cladocerans. Environ Toxicol Chem 2017; 36:2689-2697. [PMID: 28409869 DOI: 10.1002/etc.3819] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 10/16/2016] [Accepted: 04/09/2017] [Indexed: 06/07/2023]
Abstract
Cyanobacteria produce different toxic compounds that affect animal life, among them hepatotoxins and neurotoxins. Because cyanobacteria are able to produce a variety of toxic compounds at the same time, organisms may be, generally, subjected to their combined action. In the present study, we demonstrate the single and combined effects on cladocerans of cyanobacteria that produce microcystins (hepatotoxins) and saxitoxins (neurotoxins). Animals were exposed (either singly or combined) to 2 strains of cyanobacteria isolated from the same environment (Funil Reservoir, Rio de Janeiro, Brazil). The effects on clearance rate, mobility, survivorship, fecundity, population increase rate (r), and the antioxidant enzymes glutathione-S-transferase (GST) and catalase (CAT) were measured. Cladoceran species showed a variety of responses to cyanobacterial exposures, going from no effect to impairment of swimming movement, lower survivorship, fecundity, and general fitness (r). Animals ingested cyanobacteria in all treatments, although at lower rates than good food (green algae). Antioxidant defense responses were in accordance with fitness responses, suggesting that oxidative stress may be related to such effects. The present study emphasizes the need for testing combined actions of different classes of toxins, because this is often, and most likely, the scenario in a more eutrophic world with global climatic changes. Environ Toxicol Chem 2017;36:2689-2697. © 2017 SETAC.
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Affiliation(s)
| | | | | | - Valéria Freitas de Magalhães
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Stephan Pflugmacher
- Institute of Ecology, Chair of Ecological Impact Research & Ecotoxicology, Technische Universität Berlin, Berlin, Germany
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Calado SLDM, Wojciechowski J, Santos GS, Magalhães VFD, Padial AA, Cestari MM, Silva de Assis HCD. Neurotoxins in a water supply reservoir: An alert to environmental and human health. Toxicon 2017; 126:12-22. [DOI: 10.1016/j.toxicon.2016.12.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 12/04/2016] [Accepted: 12/07/2016] [Indexed: 02/01/2023]
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Liebel S, de Oliveira Ribeiro CA, de Magalhães VF, da Silva RDC, Rossi SC, Randi MAF, Filipak Neto F. Low concentrations of cylindrospermopsin induce increases of reactive oxygen species levels, metabolism and proliferation in human hepatoma cells (HepG2). Toxicol In Vitro 2015; 29:479-88. [DOI: 10.1016/j.tiv.2014.12.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 12/15/2014] [Accepted: 12/27/2014] [Indexed: 01/15/2023]
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Ferrão-Filho ADS, Soares MCS, de Magalhães VF, Azevedo SMFO. A rapid bioassay for detecting saxitoxins using a Daphnia acute toxicity test. Environ Pollut 2010; 158:2084-2093. [PMID: 20359802 DOI: 10.1016/j.envpol.2010.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 02/25/2010] [Accepted: 03/03/2010] [Indexed: 05/29/2023]
Abstract
Bioassays using Daphnia pulex and Moina micrura were designed to detect cyanobacterial neurotoxins in raw water samples. Phytoplankton and cyanotoxins from seston were analyzed during 15 months in a eutrophic reservoir. Effective time to immobilize 50% of the exposed individuals (ET50) was adopted as the endpoint. Paralysis of swimming movements was observed between approximately 0.5-3 h of exposure to lake water containing toxic cyanobacteria, followed by an almost complete recovery of the swimming activity within 24 h after being placed in control water. The same effects were observed in bioassays with a saxitoxin-producer strain of Cylindrospermopsis raciborskii isolated from the reservoir. Regression analysis showed significant relationships between ET50 vs. cell density, biomass and saxitoxins content, suggesting that the paralysis of Daphnia in lake water samples was caused by saxitoxins found in C. raciborskii. Daphnia bioassay was found to be a sensitive method for detecting fast-acting neurotoxins in natural samples, with important advantages over mouse bioassays.
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Affiliation(s)
- Aloysio da S Ferrão-Filho
- Laboratório de Avaliação e Promoção da Saúde Ambiental, Departamento de Biologia, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365, Manguinhos, Rio de Janeiro, RJ 21045-900, Brazil.
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