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Tornabene BJ, Smalling KL, Hossack BR. Effects of Harmful Algal Blooms on Amphibians and Reptiles are Under-Reported and Under-Represented. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2024; 43:1936-1949. [PMID: 38967263 DOI: 10.1002/etc.5941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/07/2024] [Accepted: 06/03/2024] [Indexed: 07/06/2024]
Abstract
Harmful algal blooms (HABs) are a persistent and increasing problem globally, yet we still have limited knowledge about how they affect wildlife. Although semi-aquatic and aquatic amphibians and reptiles have experienced large declines and occupy environments where HABs are increasingly problematic, their vulnerability to HABs remains unclear. To inform monitoring, management, and future research, we conducted a literature review, synthesized the studies, and report on the mortality events describing effects of cyanotoxins from HABs on freshwater herpetofauna. Our review identified 37 unique studies and 71 endpoints (no-observed-effect and lowest-observed-effect concentrations) involving 11 amphibian and 3 reptile species worldwide. Responses varied widely among studies, species, and exposure concentrations used in experiments. Concentrations causing lethal and sublethal effects in laboratory experiments were generally 1 to 100 µg/L, which contains the mean value of reported HAB events but is 70 times less than the maximum cyanotoxin concentrations reported in the environment. However, one species of amphibian was tolerant to concentrations of 10,000 µg/L, demonstrating potentially immense differences in sensitivities. Most studies focused on microcystin-LR (MC-LR), which can increase systemic inflammation and harm the digestive system, reproductive organs, liver, kidneys, and development. The few studies on other cyanotoxins illustrated that effects resembled those of MC-LR at similar concentrations, but more research is needed to describe effects of other cyanotoxins and mixtures of cyanotoxins that commonly occur in the environment. All experimental studies were on larval and adult amphibians; there were no such studies on reptiles. Experimental work with reptiles and adult amphibians is needed to clarify thresholds of tolerance. Only nine mortality events were reported, mostly for reptiles. Given that amphibians likely decay faster than reptiles, which have tissues that resist decomposition, mass amphibian mortality events from HABs have likely been under-reported. We propose that future efforts should be focused on seven major areas, to enhance our understanding of effects and monitoring of HABs on herpetofauna that fill important roles in freshwater and terrestrial environments. Environ Toxicol Chem 2024;43:1936-1949. Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Affiliation(s)
- Brian J Tornabene
- Northern Rocky Mountain Science Center, US Geological Survey, Missoula, Montana
| | - Kelly L Smalling
- New Jersey Water Science Center, US Geological Survey, Lawrenceville, New Jersey
| | - Blake R Hossack
- Northern Rocky Mountain Science Center, US Geological Survey, Missoula, Montana
- Wildlife Biology Program, W. A. Franke College of Forestry and Conservation, University of Montana, Missoula, Montana, USA
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Belkinova D, Stoianova D, Beshkova M, Kazakov S, Stoyanov P, Mladenov R. Current status and prognosis of Raphidiopsis raciborskii distribution in Bulgaria as part of the southeastern region of Europe. HARMFUL ALGAE 2024; 132:102578. [PMID: 38331543 DOI: 10.1016/j.hal.2024.102578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 11/21/2023] [Accepted: 01/09/2024] [Indexed: 02/10/2024]
Abstract
The cyanobacterial species Raphidiopsis raciborskii (Wołoszyńska) Aguilera et al. has a high invasiveness potential, which in less than a century leads to its cosmopolitan spread. In the temperate climate of Europe, R. raciborskii has been reported in many countries, but there is still a lack of detailed information about the current status of its distribution in lakes of Bulgaria, as a part of the southeastern range of its spread in Europe. We investigated the distribution of the species using data on the phytoplankton of 122 lakes surveyed during 13-years period (2009-2022). The species was found in 33 lakes (up to 324 m asl), and 14 new localities were registered during the studied period. The results reveal that the number of lakes with the presence of R. raciborskii (27 % of all research lakes) and its contribution to the total phytoplankton biomass, has increased significantly over the last decade. The species has successfully adapted and dominated the phytoplankton in 9 lakes, forming a bloom in 8 of them. The dominant position of R. raciborskii causes loss of species and functional diversity of phytoplankton and displaces the native bloom-forming cyanobacteria. Lakes with and without the species were compared based on the available data on bioclimatic and local environmental variables. Statistically significant differences were established with respect to water transparency, conductivity, maximum depth and maximum air temperature in the warmest month. Species distribution models (SDMs) were used to identify lakes in high risk of future invasion by R. raciborskii. The results of the SDMs implementation confirmed the high maximum air temperature and low water transparency to be important predictors of the occurrence of R. raciborskii in freshwater lakes in Bulgaria. In the areas with high summer temperatures the most suitable for R. raciborskii development were found to be shallow polymictic or medium deep lakes with small surface area and low water transparency. In areas with a suitable climate, the large, deep reservoirs with high transparency as well as macrophyte dominated lakes have a low probability of occurrence of R. raciborskii. Future colonization of lakes above 500 m asl (but most likely below 700 m asl) is also possible, especially in the conditions of global warming. SDMs account for climatic and biogeographic differences of lakes and could help in elucidating the underlying factors that control the occurrence and adaptation of R. raciborskii in a given area.
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Affiliation(s)
- Detelina Belkinova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Botany and Biological education, Faculty of Biology, University of Plovdiv "Paisii Hilendarski", Bulgaria
| | - Desislava Stoianova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria.
| | - Mihaela Beshkova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Stefan Kazakov
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Plamen Stoyanov
- Department of Botany and Biological education, Faculty of Biology, University of Plovdiv "Paisii Hilendarski", Bulgaria; Department of Bioorganic Chemistry, Faculty of Pharmacy, Medical University of Plovdiv, Bulgaria
| | - Rumen Mladenov
- Department of Botany and Biological education, Faculty of Biology, University of Plovdiv "Paisii Hilendarski", Bulgaria; Department of Bioorganic Chemistry, Faculty of Pharmacy, Medical University of Plovdiv, Bulgaria
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Toušová Z, Priebojová J, Javůrek J, Večerková J, Lepšová-Skácelová O, Sychrová E, Smutná M, Hilscherová K. Estrogenic and retinoid-like activity in stagnant waters with mass occurrence of water blooms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158257. [PMID: 36037903 DOI: 10.1016/j.scitotenv.2022.158257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 08/19/2022] [Accepted: 08/20/2022] [Indexed: 06/15/2023]
Abstract
Stagnant freshwaters can be affected by anthropogenic pollution and eutrophication that leads to massive growth of cyanobacteria and microalgae forming complex water blooms. These can produce various types of bioactive compounds, some of which may cause embryotoxicity, teratogenicity, endocrine disruption and impair animal or human health. This study focused on potential co-occurrence of estrogenic and retinoid-like activities in diverse stagnant freshwaters affected by phytoplankton blooms with varying taxonomic composition. Samples of phytoplankton bloom biomass and its surrounding water were collected from 17 independent stagnant water bodies in the Czech Republic and Hungary. Total estrogenic equivalents (EEQ) of the most potent samples reached up to 4.9 ng·g-1 dry mass (dm) of biomass extract and 2.99 ng·L-1 in surrounding water. Retinoic acid equivalent (REQ) measured by in vitro assay reached up to 3043 ng·g-1 dm in phytoplankton biomass and 1202 ng·L-1in surrounding water. Retinoid-like and estrogenic activities at some sites exceeded their PNEC and effect-based trigger values, respectively. The observed effects were not associated with any particular species of cyanobacteria or algae dominating the water blooms nor related to phytoplankton density. We found that taxonomically diverse phytoplankton communities can produce and release retinoid-like compounds to surrounding water, while estrogenic potency is likely related to estrogens of anthropogenic origin adsorbed to phytoplankton biomass. Retinoids occurring in water blooms are ubiquitous signalling molecules, which can affect development and neurogenesis. Selected water bloom samples (both water and biomass extracts) with retinoid-like activity caused effects on neurodifferentiation in vitro corresponding to those of equivalent all-trans-retinoic acid concentrations. Co-occurrence of estrogenic and retinoid-like activities in stagnant water bodies as well as the potential of compounds produced by water blooms to interfere with neural differentiation should be considered in the assessment of risks associated with water blooms, which can comprise complex mixtures of natural and anthropogenic bioactive compounds.
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Affiliation(s)
- Zuzana Toušová
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Jana Priebojová
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Jakub Javůrek
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Jaroslava Večerková
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Olga Lepšová-Skácelová
- Department of Botany, Faculty of Science, University of South Bohemia, Na Zlaté stoce 1, České Budějovice, Czech Republic
| | - Eliška Sychrová
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Marie Smutná
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Klára Hilscherová
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
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4
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Pípal M, Novák J, Rafajová A, Smutná M, Hilscherová K. Teratogenicity of retinoids detected in surface waters in zebrafish embryos and its predictability by in vitro assays. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 246:106151. [PMID: 35390581 DOI: 10.1016/j.aquatox.2022.106151] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 03/08/2022] [Accepted: 03/25/2022] [Indexed: 06/14/2023]
Abstract
Retinoids are newly detected compounds in aquatic ecosystems associated with cyanobacterial water blooms. Their potential health risks are only scarcely described despite numerous detections of all-trans retinoic acid (ATRA) and its derivatives in the environment. Besides the known teratogen ATRA there is only little or no information about their potency and namely their effects in vivo. We characterize ATRA and 8 other retinoids reported to occur in the environment for their bioactivity and teratogenicity using four in vitro reporter gene assays and zebrafish (Danio rerio) embryotoxicity assay. Our results document the ability of these compounds to interfere with retinoid signalling and cause teratogenicity at environmentally relevant levels with EC50 values at nM (hundreds of ng/L) levels and teratogenic indexes ranging from 2.8 (9cis retinoic acid) to 15.8 (retinal). The relative potency of individual compounds for teratogenicity ranged from 0.059 (retinal) to 0.96 (5,6-epoxy ATRA) when compared to ATRA. An environmentally relevant mixture of retinoids was tested showing good predictability of teratogenicity from the in vitro activities and additive toxicity of the mixture. The high teratogenicity of the newly described compounds associated with cyanobacteria presents a concern for developmental stages due to high conservation of the retinoid signalling across vertebrates.
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Affiliation(s)
- Marek Pípal
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Kamenice, Brno 62500 , Czech Republic
| | - Jiří Novák
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Kamenice, Brno 62500 , Czech Republic
| | - Aneta Rafajová
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Kamenice, Brno 62500 , Czech Republic
| | - Marie Smutná
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Kamenice, Brno 62500 , Czech Republic
| | - Klára Hilscherová
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Kamenice, Brno 62500 , Czech Republic.
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Yeung KWY, Lai RWS, Zhou GJ, Leung KMY. Concentration-response of six marine species to all-trans-retinoic acid and its ecological risk to the marine environment. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 235:113455. [PMID: 35358921 DOI: 10.1016/j.ecoenv.2022.113455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/18/2022] [Accepted: 03/23/2022] [Indexed: 06/14/2023]
Abstract
Being a class of vitamin A's main derivatives, retinoic acids (RAs) are important to animals' growth and development. Previous studies demonstrated that exposure of excessive amounts of RAs would lead to malformation and abnormal development in aquatic animals such as amphibians and fishes. Currently, there are only limited toxicity data of RAs available for freshwater species, while those for marine species are seriously lacking. This study aimed to fill such data gap by conducting toxicity tests on six marine species (i.e., one microalga, four invertebrates and one fish) towards the exposure to all-trans-RA (at-RA), which is the most widely distributed RA in the environment. Results showed that the embryo of medaka fish Oryzias melastigma was the most sensitive towards the exposure of at-RA while the gastropod Monodonta labio was the least sensitive. A species sensitivity distribution (SSD) was constructed based on the experimental results generated from the present study. An interim marine-specific predicted no-effect concentration (PNEC) of at-RA was derived at 2300 ng/L. By computing the hazard quotients using the interim marine-specific PNEC and available measured and predicted concentrations of RAs, we found the current levels of RAs posed no immediate risks to the marine environment of Hong Kong. The interim marine-specific PNEC was more than 500-fold of freshwater-specific PNEC (i.e., 3.93 ng/L), indicating that marine species were generally less sensitive than their freshwater counterparts towards RAs. This was the first study to document the concentration-response of various marine species towards at-RA exposure and construct the marine-specific SSD for assessing the ecological risk of at-RA towards the marine environment. Since various forms of RAs and their metabolites often coexist in aquatic environments, further studies should investigate their combined toxicity to an array of marine species of different trophic levels with consideration of chronic exposure scenarios.
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Affiliation(s)
- Katie Wan Yee Yeung
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Racliffe Weng Seng Lai
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Guang-Jie Zhou
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.
| | - Kenneth Mei Yee Leung
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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Smutna M, Vecerkova J, Priebojova J, Pipal M, Krauss M, Hilscherova K. Variability in retinoid-like activity of extracellular compound mixtures produced by wide spectra of phytoplankton species and contributing metabolites. JOURNAL OF HAZARDOUS MATERIALS 2021; 414:125412. [PMID: 34030396 DOI: 10.1016/j.jhazmat.2021.125412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/22/2021] [Accepted: 02/10/2021] [Indexed: 06/12/2023]
Abstract
Some phytoplankton species were shown to produce teratogenic retinoids. This study assessed the variability in the extracellular production of compounds with retinoid-like activity for 50 independent cultivations of wide spectra of species including 12 cyanobacteria (15 strains) and 4 algae of different orders. Extracellular retinoid-like activity was detected for repeated cultivations of six cyanobacteria. The results were consistent for some species including Microcystis aeruginosa and Aphanizomenon gracile. The detected retinoid-like activities ranged from below the limit of quantification of 16 ng/L to over 6 µg all-trans retinoic acid (ATRA) equivalent/L. Nontargeted virtual fractionation together with suspect screening approach enabled to identify some retinoid-like compounds in exudates, including ATRA, 9/13-cis retinoic acid, all-trans 5,6-epoxy retinoic acid, 4keto-ATRA, 4keto-retinal, 4hydroxy-ATRA, and retinal. Most of them were for the first time repeatedly detected in exudates of all studied algae (at ng/L levels) and cyanobacteria. Their relative potencies ranged from 0.018 (retinal) to 1 compared to ATRA. They accounted for less than 0.1-50% of total detected retinoid-like activity. The high detected activities and concentrations of retinoids in some samples and their direct accessibility from exudates document potential risk of developmental toxicity for organisms in proximity of massive water blooms.
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Affiliation(s)
- Marie Smutna
- RECETOX, Masaryk University, Faculty of Science, Brno, Czech Republic
| | | | - Jana Priebojova
- RECETOX, Masaryk University, Faculty of Science, Brno, Czech Republic
| | - Marek Pipal
- RECETOX, Masaryk University, Faculty of Science, Brno, Czech Republic
| | - Martin Krauss
- UFZ Helmholtz Centre for Environmental Research, Permoserstraße 15, 04318 Leipzig, Germany
| | - Klara Hilscherova
- RECETOX, Masaryk University, Faculty of Science, Brno, Czech Republic.
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Pípal M, Legradi J, Smutná M, Kočí T, Priebojová J, Bláhová L, Krauss M, Hilscherová K. Neurobehavioral effects of cyanobacterial biomass field extracts on zebrafish embryos and potential role of retinoids. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 228:105613. [PMID: 32949975 DOI: 10.1016/j.aquatox.2020.105613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/27/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
Cyanobacteria are known for their ability to produce and release mixtures of up to thousands of compounds into the environment. Recently, the production of novel metabolites, retinoids, was reported for some cyanobacterial species along with teratogenic effects of samples containing these compounds. Retinoids are natural endogenous substances derived from vitamin A that play a crucial role in early vertebrate development. Disruption of retinoid signalling- especially during the early development of the nervous system- might lead to major malfunctions and malformations. In this study, the toxicity of cyanobacterial biomass samples from the field containing retinoids was characterized by in vivo and in vitro bioassays with a focus on the potential hazards towards nervous system development and function. Additionally, in order to identify the compounds responsible for the observed in vitro and in vivo effects the complex cyanobacterial extracts were fractionated (C18 column, water-methanol gradient) and the twelve obtained fractions were tested in bioassays. In all bioassays, all-trans retinoic acid (ATRA) was tested along with the environmental samples as a positive control. Retinoid-like activity (mediated via the retinoic acid receptor, RAR) was measured in the transgenic cell line p19/A15. The in vitro assay showed retinoid-like activity by specific interaction with RAR for the biomass samples. Neurotoxic effects of selected samples were studied on zebrafish (Danio rerio) embryos using the light/dark transition test (Viewpoint, ZebraLab system) with 120 hpf larvae. In the behavioural assay, the cyanobacterial extracts caused significant hyperactivity in zebrafish at 120 hpf after acute exposure (3 h prior to the measurement) at concentrations below the teratogenicity LOEC (0.2 g dw L-1). Similar effect was observed after exposure to fractions of the extracts with detected retinoid-like activity and additive effect was observed after combining the fractions. However, the effect on behaviour was not observed after exposure to ATRA only. To provide additional insight into the behavioural effects and describe the underlying mechanism gene expression of selected biomarkers was measured. We evaluated an array of 28 genes related to general toxicity, neurodevelopment, retinoid and thyroid signalling. We detected several affected genes, most notably, the Cyp26 enzymes that control endogenous ATRA concentration, which documents an effect on retinoid signalling.
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Affiliation(s)
- Marek Pípal
- RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jessica Legradi
- Institute for Environmental Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Marie Smutná
- RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Tereza Kočí
- RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jana Priebojová
- RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Lucie Bláhová
- RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Martin Krauss
- UFZ-Helmholtz Centre for Environmental Research, Department Effect-Directed Analysis, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Klára Hilscherová
- RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic.
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Yeung KWY, Zhou GJ, Hilscherová K, Giesy JP, Leung KMY. Current understanding of potential ecological risks of retinoic acids and their metabolites in aquatic environments. ENVIRONMENT INTERNATIONAL 2020; 136:105464. [PMID: 31926435 DOI: 10.1016/j.envint.2020.105464] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/13/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
In animals, retinoic acids (RAs), one of the main derivatives of vitamin A, are crucial for a variety of physiological processes. RAs, including all-trans-RA, 9-cis-RA, 13-cis-RA, and their corresponding metabolites (i.e., all-trans-4-oxo-RA, 9-cis-4-oxo-RA and 13-cis-4-oxo-RA) can be excreted through urination from humans and animals. Sewage treatment plants (STPs) are a significant source of RAs and 4-oxo-RAs into aquatic environments. RAs and 4-oxo-RAs can be identified and quantified by use of liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). RAs and 4-oxo-RAs have been reported in various environmental matrices including rivers, lakes, reservoirs and coastal marine environments as well as in sewage effluents discharged from STPs. Greater concentrations of RAs and 4-oxo-RAs have been observed during blooms of cyanobacteria and microalgae, suggesting that cyanobacteria and microalgae are natural sources of RAs and 4-oxo-RAs in aquatic environments. These potential sources of RAs and 4-oxo-RAs raise concerns about their concentrations and risks in aquatic environments because excessive intake of these chemicals can result in abnormal morphological development in animals. Teratogenic effects were observed in amphibians, fish embryos, gastropods, mammals and birds when exposed to RAs. This review summarizes sources, concentrations, adverse effects and ecological risks of RAs and 4-oxo-RAs in aquatic environments. An interim, predicted no-effect concentration (PNEC) of RAs (in terms of at-RA) for freshwater environments was determined to be 3.93 ng/L at-RA equivalents. Based on limited data on concentrations of RAs in freshwater ecosystems, their hazard quotients were found to range from zero to 16.41, depending on the environmental conditions of receiving waters. Ecological risks of RAs in marine environments are yet to be explored due to the paucity of data related to both their concentrations in marine environment and toxic potencies to marine species. This review updates current knowledge of RAs and 4-oxo-RAs in aquatic environments and calls for more studies on their concentrations and fate in aquatic environments, especially estuarine and coastal marine environments with a view to enabling a comprehensive assessment of their ecological risks around the globe.
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Affiliation(s)
- Katie Wan Yee Yeung
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Guang-Jie Zhou
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.
| | - Klára Hilscherová
- RECETOX, Faculty of Science, Masaryk University, Kamenice 753/5, Pavilion A29, 625 00 Brno, Czech Republic
| | - John P Giesy
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, SK, Canada; Department of Environmental Science, Baylor University, Waco, TX, United States
| | - Kenneth Mei Yee Leung
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China; State Key Laboratory of Marine Pollution (City University of Hong Kong), Tat Chee Avenue, Kowloon, Hong Kong, China.
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Pipal M, Priebojova J, Koci T, Blahova L, Smutna M, Hilscherova K. Field cyanobacterial blooms producing retinoid compounds cause teratogenicity in zebrafish embryos. CHEMOSPHERE 2020; 241:125061. [PMID: 31877619 DOI: 10.1016/j.chemosphere.2019.125061] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 10/03/2019] [Accepted: 10/04/2019] [Indexed: 06/10/2023]
Abstract
Cyanobacteria routinely release potentially harmful bioactive compounds into the aquatic environment. Several recent studies suggested a potential link between the teratogenicity of effects caused by cyanobacteria and production of retinoids. To investigate this relationship, we analysed the teratogenicity of field-collected cyanobacterial bloom samples by means of an in vivo zebrafish embryo test, an in vitro reporter gene bioassay and by the chemical analysis of retinoids. Extracts of biomass from cyanobacterial blooms with the dominance of Microcystis aeruginosa and Aphanizomenon klebahnii were collected from water bodies in the Czech Republic and showed significant retinoid-like activity in vitro, as well as high degrees of teratogenicity in vivo. Chemical analysis was then used to identify a set of retinoids in ng per gram of dry weight concentration range. Subsequent fractionation and bioassay-based characterization identified two fractions with significant in vitro retinoid-like activity. Moreover, in most of the retinoids eluted from these fractions, teratogenicity with malformations typical for retinoid signalling disruption was observed in zebrafish embryos after exposure to the total extracts and these in vitro effective fractions. The zebrafish embryo test proved to be a sensitive toxicity indicator of the biomass extracts, as the teratogenic effects occurred at even lower concentrations than those expected from the activity detected in vitro. In fact, teratogenicity with retinoid-like activity was detected at concentrations that are commonly found in biomasses and even in bulk water surrounding cyanobacterial blooms. Overall, these results provide evidence of a link between retinoid-like activity, teratogenicity and the retinoids produced by cyanobacterial water blooms in the surrounding environment.
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Affiliation(s)
- Marek Pipal
- RECETOX Faculty of Science Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Jana Priebojova
- RECETOX Faculty of Science Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Tereza Koci
- RECETOX Faculty of Science Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Lucie Blahova
- RECETOX Faculty of Science Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Marie Smutna
- RECETOX Faculty of Science Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Klara Hilscherova
- RECETOX Faculty of Science Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.
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Wang S, Bi W, Liu Y, Cheng J, Sun W, Wu G, Xu X. The Antagonist of Retinoic Acid Receptor α, ER-50891 Antagonizes the Inhibitive Effect of All-Trans Retinoic Acid and Rescues Bone Morphogenetic Protein 2-Induced Osteoblastogenic Differentiation. DRUG DESIGN DEVELOPMENT AND THERAPY 2020; 14:297-308. [PMID: 32158187 PMCID: PMC6985983 DOI: 10.2147/dddt.s215786] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 12/04/2019] [Indexed: 12/18/2022]
Abstract
Background Hypervitaminosis A, alcoholism or medical treatment for acute promyelocytic leukaemia may cause unphysiologically high accumulation of all-trans retinoic acid (ATRA), which could inhibit osteoblastogenesis, thereby triggering osteoporosis. We have shown that bone morphogenetic protein-2 (BMP-2) can only partially antagonize the inhibitive effects of ATRA. In this study, we hypothesized that antagonists of retinoic acid receptors (RARs) could further antagonize the inhibitive effect of ATRA and rescue BMP2-induced osteoblastogenesis. Materials and Methods We first screened the dose-dependent effects of the specific antagonists of RAR α, β and γ and transforming growth factor-beta receptor (ER-50891, LE-135, MM11253, and SB-43142, respectively) on ATRA-induced inhibition of the total cell metabolic activity and proliferation of preosteoblasts. We selected ER-50891 and tested its effects on osteoblastogenesis with the presence or absence of 1 μM ATRA and/or 200 ng/mL BMP-2. We measured the following parameters: Alkaline phosphatase activity (ALP), osteocalcin (OCN) expression and extracellular matrix mineralization as well as the level of phosphorylated Smad1/5. Results ER-50891 but not LE-135, MM11253, or SB-431542 significantly antagonized the inhibition of ATRA and enhanced the total cell metabolic activity and proliferation of preosteoblasts. Dose-dependent assays show ER-50891 could also rescue ATRA inhibited OCN expression and mineralization with or without the induction of BMP. ER-50891 also suppressed the ALP activity that was synergistically enhanced by BMP and ATRA. Neither ATRA, nor ER-50891 or their combination significantly affected the level of BMP-induced phosphorylated Smad1/5. Conclusion The antagonist of RARα, ER-50891 could significantly attenuate ATRA’s inhibitive effects on BMP 2-induced osteoblastogenesis.
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Affiliation(s)
- Siqian Wang
- Department of Implantology, School and Hospital of Stomatology, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, Shandong Province, People's Republic of China
| | - Wenjuan Bi
- College of Stomatology, North China University of Science and Technology, Tangshan, Hebei Province, People's Republic of China
| | - Yi Liu
- Key Laboratory of Oral Medicine, Guangzhou Institute of Oral Disease, Stomatology Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Jiayi Cheng
- Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam (UvA) and Vrije Universiteit Amsterdam (VU), Amsterdam, The Netherlands
| | - Wei Sun
- The Affiliated Stomatology Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, People's Republic of China
| | - Gang Wu
- Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam (UvA) and Vrije Universiteit Amsterdam (VU), Amsterdam, The Netherlands
| | - Xin Xu
- Department of Implantology, School and Hospital of Stomatology, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, Shandong Province, People's Republic of China
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11
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Eagles EJ, Benstead R, MacDonald S, Handy R, Hutchinson TH. Impacts of the mycotoxin zearalenone on growth and photosynthetic responses in laboratory populations of freshwater macrophytes (Lemna minor) and microalgae (Pseudokirchneriella subcapitata). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 169:225-231. [PMID: 30448705 DOI: 10.1016/j.ecoenv.2018.10.101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 10/25/2018] [Accepted: 10/26/2018] [Indexed: 06/09/2023]
Abstract
Mycotoxins are an important class of chemicals of emerging concern, recently detected in aquatic environments, potentially reflecting the influence of fungicide resistance and climatic factors on fungal diseases in agricultural crops. Zearalenone (ZON) is a mycotoxin formed by Fusarium spp. and is known for its biological activity in animal tissues; both in vitro and in vivo. ZON has been reported in US and Polish surface waters at 0.7 - 96 ng/L, with agricultural run-off and wastewater treatment plants being the likely sources of mycotoxins. As some mycotoxins can induce phytotoxicity, laboratory studies were conducted to evaluate the toxicity of ZON (as measured concentrations) to freshwater algae (Pseudokirchneriella subcapitata) and macrophytes (Lemna minor) following OECD test guidelines 201 and 221, respectively. Zinc sulphate was used as a positive control. In the OECD 201 algal static study (72 h at 24 ± 1 °C), exposure to ZON gave average specific growth rate (cell density) EC50 and yield (cell density) EC50 values of > 3.1 and 0.92 (0.74 - 1.8) mg/L, respectively. ZON was less toxic in the OECD 221 static study and after 7 d at 24 ± 1 °C. L. minor growth was significantly reduced based on frond number and frond area at 11.4 mg ZON/L, showing a higher tolerance than reported for other mycotoxins with Lemna spp. Chlorophyll fluorescence parameters were used as biomarkers of impacts on photosystem II efficiency, with no effect seen in algae but, with responses being observed in L. minor between 5.2 - 14.4 mg ZON/L. ZON toxicity seen here is not of immediate concern in context with environmental levels, but this study highlights that other freshwater organisms including algae are more sensitive to mycotoxins than Lemna sp., the only current source of toxicity data for freshwater plants.
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Affiliation(s)
- Emily J Eagles
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA, UK
| | - Rachel Benstead
- FERA Science Ltd., National Agri-Food Innovation Campus, Sand Hutton, York YO41 1LZ, UK
| | - Susan MacDonald
- FERA Science Ltd., National Agri-Food Innovation Campus, Sand Hutton, York YO41 1LZ, UK
| | - Richard Handy
- School of Biological & Marine Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA, UK
| | - Thomas H Hutchinson
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA, UK.
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12
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Miles JA, Machattou P, Nevin-Jones D, Webb ME, Millard A, Scanlan DJ, Taylor PC. Identification of a cyanobacterial aldehyde dehydrogenase that produces retinoic acid in vitro. Biochem Biophys Res Commun 2019; 510:27-34. [DOI: 10.1016/j.bbrc.2018.12.171] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 12/27/2018] [Indexed: 11/15/2022]
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13
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Falfushynska H, Horyn O, Brzozowska A, Fedoruk O, Buyak B, Poznansky D, Poniedziałek B, Kokociński M, Rzymski P. Is the presence of Central European strains of Raphidiopsis (Cylindrospermopsis) raciborskii a threat to a freshwater fish? An in vitro toxicological study in common carp cells. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 206:105-113. [PMID: 30472479 DOI: 10.1016/j.aquatox.2018.11.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/11/2018] [Accepted: 11/13/2018] [Indexed: 06/09/2023]
Abstract
As yet European strains of Raphidiopsis raciborskii (previously Cylindrospermopsis raciborskii) have not been found to produce known cyanotoxins although their extracts have caused adverse effects in mammals, as shown using in vitro and in vivo experimental models. The present study investigated whether R. raciborskii isolated from Western Poland and Ukraine can affect fish cells using in vitro exposures of hepatocytes and red blood cells (RBC), and brain homogenates obtained from common carp (Cyprinus carpio) to 1.0% and 0.1% extracts of 7 strains. The studied extracts evoked different responses of catalase activity in hepatocytes with both increase and decrease observed under low and high concentrations. The cellular thiol pool was also altered with most extracts inducing a decrease in the activity of glutathione-S-transferase, and Ukrainian strains leading to an increase in glutathione level and a decrease in metallothionein content. All the studied extracts induced comparable reactive oxygen species formation, lipid peroxidation, protein carbonylation and DNA fragmentation in hepatocytes, and all but one increased the activity of caspase-3. Only one extract caused lysosomal membrane destabilization as measured by neutral red retention in RBC. In contrast to extracts of Ukrainian isolates, exposure of brain homogenates to extracts of Polish strains induced an increase in acetylcholinesterase activity suggesting the neurotoxic action of their exudates. The results indicate that both Polish and Ukrainian strains of R. raciborskii may pose a toxicological risk to freshwater fish, and further, that Polish strains may produce compound(s) evoking neurotoxic effects.
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Affiliation(s)
- Halina Falfushynska
- Ternopil Volodymyr Hnatiuk National Pedagogical University, Ternopil, Ukraine
| | - Oksana Horyn
- Ternopil Volodymyr Hnatiuk National Pedagogical University, Ternopil, Ukraine
| | - Agnieszka Brzozowska
- Department of Hydrobiology, Faculty of Biology, Adam Mickiewicz University in Poznan, Poznań, Poland
| | - Olga Fedoruk
- Ternopil Volodymyr Hnatiuk National Pedagogical University, Ternopil, Ukraine
| | - Bogdan Buyak
- Ternopil Volodymyr Hnatiuk National Pedagogical University, Ternopil, Ukraine
| | - Dmytro Poznansky
- Ternopil Volodymyr Hnatiuk National Pedagogical University, Ternopil, Ukraine
| | - Barbara Poniedziałek
- Department of Environmental Medicine, Poznan University of Medical Sciences, Poznań, Poland
| | - Mikołaj Kokociński
- Department of Hydrobiology, Faculty of Biology, Adam Mickiewicz University in Poznan, Poznań, Poland
| | - Piotr Rzymski
- Department of Environmental Medicine, Poznan University of Medical Sciences, Poznań, Poland.
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Rzymski P, Horyn O, Budzyńska A, Jurczak T, Kokociński M, Niedzielski P, Klimaszyk P, Falfushynska H. A report of Cylindrospermopsis raciborskii and other cyanobacteria in the water reservoirs of power plants in Ukraine. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:15245-15252. [PMID: 29680888 PMCID: PMC5973952 DOI: 10.1007/s11356-018-2010-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/11/2018] [Indexed: 06/01/2023]
Abstract
The occurrence of cyanobacteria in freshwaters attracts much attention due to its associated health threats and ecological implications. Yet data on the composition of cyanobacteria taxa and toxigenicity in some regions is still scarce. Here, we explored the occurrence of cyanobacteria and cyanotoxins in three locations in Ukraine (reservoir for Kasperivtsi Hydrothermal Power Plant and outflowing River Seret, and cooling pond of Khmelnytsky Atomic Power Plant) in summer 2017. Cyanobacteria were a dominant fraction at all stations. A number of potent-toxin producers were identified including Cylindrospermopsis raciborskii, Aphanizomenon gracile, Dolichospermum flos-aquae, and Planktothrix agardhii. Screening for the presence of dissolved and particulate content of microcystins (-LR, -YR, and -RR), cylindrospermopsin, and anatoxin-a yielded negative results. The studied waters displayed no toxicity in human platelets in vitro. Further toxicological and ecological studies are necessary to evaluate the potential presence of cyanotoxin producers in Ukraine.
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Affiliation(s)
- Piotr Rzymski
- Department of Environmental Medicine, Poznan University of Medical Sciences, Poznań, Poland.
| | - Oksana Horyn
- Research Laboratory of Comparative Biochemistry and Molecular Biology, Ternopil National Pedagogical University, Ternopil, Ukraine
| | | | - Tomasz Jurczak
- Department of Applied Ecology, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | | | | | - Piotr Klimaszyk
- Department of Water Protection, Adam Mickiewicz University, Poznań, Poland
| | - Halina Falfushynska
- Research Laboratory of Comparative Biochemistry and Molecular Biology, Ternopil National Pedagogical University, Ternopil, Ukraine
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Priebojová J, Hilscherová K, Procházková T, Sychrová E, Smutná M. Intracellular and extracellular retinoid-like activity of widespread cyanobacterial species. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 150:312-319. [PMID: 29291583 DOI: 10.1016/j.ecoenv.2017.12.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 12/19/2017] [Accepted: 12/20/2017] [Indexed: 06/07/2023]
Abstract
Cyanobacterial species produce wide range of bioactive compounds. This study characterized production of retinoid-like compounds with embryotoxic and teratogenic potential by commonly occurring cyanobacterial species with tendency to form massive water blooms. The major goal was to simultaneously assess the intracellular and extracellular retinoid-like activity from several independent cultivations of one coccal (Microcystis aeruginosa) and four filamentous cyanobacteria (Aphanizomenon gracile, Cylindrospermopsis raciborskii, Limnothrix redekeii, and Planktothrix agardhii) and characterize the variability in its production among cultivations. The retinoid-like activity was evaluated by in vitro assay along with chemical analyses of nine retinoids: all-trans retinoic acid (ATRA), 9-cis retinoic acid (9cis-RA), 13cis-RA, 13cis-RA methyl ester, 5,6 epoxy-RA, 4keto-ATRA, 4keto-retinal, 4hydoxy-retinoic acid (4OH-ATRA), retinal and retinol. The production of retinoid-like compounds was recalculated per volume, per biomass dry weight and per cell to provide relevant data for risk assessment in relation to occurrence of massive water blooms in the environment. Total produced retinoid-like activity of five selected species ranged from 170 to 25,600ng ATRA-equivalents (REQ)/g dm corresponding to 0.001-0.392ng REQ/106 cyanobacterial cells. Results from chemical analyses showed that all tested extracts contained 4keto-ATRA and retinal. All-trans retinoic acid, 9/13cis-retinoic acid and 5,6 epoxy-retinoic acid were detected in most exudate and extract samples. The reported results of recalculated total retinoid-like activity enable potential predictions of its production by the studied species in water blooms of known cell densities relevant for risk assessment.
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Affiliation(s)
- Jana Priebojová
- RECETOX - Research Centre for Toxic Compounds in the Environment, Masaryk University, Faculty of Science, Brno Czech Republic
| | - Klára Hilscherová
- RECETOX - Research Centre for Toxic Compounds in the Environment, Masaryk University, Faculty of Science, Brno Czech Republic
| | - Tereza Procházková
- RECETOX - Research Centre for Toxic Compounds in the Environment, Masaryk University, Faculty of Science, Brno Czech Republic
| | - Eliška Sychrová
- RECETOX - Research Centre for Toxic Compounds in the Environment, Masaryk University, Faculty of Science, Brno Czech Republic
| | - Marie Smutná
- RECETOX - Research Centre for Toxic Compounds in the Environment, Masaryk University, Faculty of Science, Brno Czech Republic.
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16
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Zi J, Pan X, MacIsaac HJ, Yang J, Xu R, Chen S, Chang X. Cyanobacteria blooms induce embryonic heart failure in an endangered fish species. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2018; 194:78-85. [PMID: 29169051 DOI: 10.1016/j.aquatox.2017.11.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/13/2017] [Accepted: 11/15/2017] [Indexed: 06/07/2023]
Abstract
Cyanobacterial blooms drive water-quality and aquatic-ecosystem deterioration in eutrophic lakes worldwide, mainly owing to their harmful, secondary metabolites. The response of fish exposed to these cyanobacterial chemicals, however, remains largely unknown. In this paper, we employed an endangered fish species (Sinocyclocheilus grahami) in Dianchi Lake, China to evaluate the risks of cell-free exudates (MaE) produced by a dominant cyanobacterium (Microcystis aeruginosa) on embryo development, as well as the molecular mechanisms responsible. MaE (3d cultured) caused a reduction of fertilization (35.4%) and hatching (15.5%) rates, and increased mortality rates (≤90.0%) and malformation rate (27.6%), typically accompanied by heart failure. Proteomics analysis revealed that two greatest changed proteins - protein S100A1 (over-expressed 26 times compared with control) and myosin light chain (under-expressed 25 fold) - are closely associated with heart function. Further study revealed that heart failure was due to calcium ion imbalance and malformed cardiac structure. We conclude that harmful secondary metabolites from cyanobacteria may adversely affect embryo development in this endangered fish, and possibly contribute to its disappearance and unsuccessful recovery in Dianchi Lake. Hazardous consequences of substances released by cyanobacteria should raise concerns for managers addressing recovery of this and other imperiled species in affected lakes.
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Affiliation(s)
- Jinmei Zi
- School of Ecology and Environmental Sciences, Yunnan University, Kunming 650091, PR China
| | - Xiaofu Pan
- Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, PR China
| | - Hugh J MacIsaac
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9 B 3P4, Canada; School of Ecology and Environmental Sciences, Yunnan University, Kunming 650091, PR China
| | - Junxing Yang
- Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, PR China
| | - Runbing Xu
- School of Ecology and Environmental Sciences, Yunnan University, Kunming 650091, PR China
| | - Shanyuan Chen
- School of Ecology and Environmental Sciences, Yunnan University, Kunming 650091, PR China
| | - Xuexiu Chang
- School of Ecology and Environmental Sciences, Yunnan University, Kunming 650091, PR China.
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