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Tebben J, Zurhelle C, Tubaro A, Samdal IA, Krock B, Kilcoyne J, Sosa S, Trainer VL, Deeds JR, Tillmann U. Structure and toxicity of AZA-59, an azaspiracid shellfish poisoning toxin produced by Azadinium poporum (Dinophyceae). HARMFUL ALGAE 2023; 124:102388. [PMID: 37164556 DOI: 10.1016/j.hal.2023.102388] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/13/2023] [Accepted: 01/18/2023] [Indexed: 05/12/2023]
Abstract
To date, the putative shellfish toxin azaspiracid 59 (AZA-59) produced by Azadinium poporum (Dinophyceae) has been the only AZA found in isolates from the Pacific Northwest coast of the USA (Northeast Pacific Ocean). Anecdotal reports of sporadic diarrhetic shellfish poisoning-like illness, with the absence of DSP toxin or Vibrio contamination, led to efforts to look for other potential toxins, such as AZAs, in water and shellfish from the region. A. poporum was found in Puget Sound and the outer coast of Washington State, USA, and a novel AZA (putative AZA-59) was detected in low quantities in SPATT resins and shellfish. Here, an A. poporum strain from Puget Sound was mass-cultured and AZA-59 was subsequently purified and structurally characterized. In vitro cytotoxicity of AZA-59 towards Jurkat T lymphocytes and acute intraperitoneal toxicity in mice in comparison to AZA-1 allowed the derivation of a provisional toxicity equivalency factor of 0.8 for AZA-59. Quantification of AZA-59 using ELISA and LC-MS/MS yielded reasonable quantitative results when AZA-1 was used as an external reference standard. This study assesses the toxic potency of AZA-59 and will inform guidelines for its potential monitoring in case of increasing toxin levels in edible shellfish.
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Affiliation(s)
- Jan Tebben
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Section Ecological Chemistry, Am Handelshafen 12, Bremerhaven, 27570, Germany.
| | - Christian Zurhelle
- University of Bremen, Department of Biology and Chemistry, Marine Chemistry, Leobener Straße 6, Bremen, 28359, Germany
| | - Aurelia Tubaro
- Department of Life Sciences, University of Trieste, Via A. Valerio 6, Trieste, 34127, Italy
| | | | - Bernd Krock
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Section Ecological Chemistry, Am Handelshafen 12, Bremerhaven, 27570, Germany
| | - Jane Kilcoyne
- Marine Institute, Rinville, Oranmore, County Galway H91 R673, Ireland
| | - Silvio Sosa
- Department of Life Sciences, University of Trieste, Via A. Valerio 6, Trieste, 34127, Italy
| | - Vera L Trainer
- Olympic Natural Resources Center, University of Washington, 1455 S. Forks Ave, Forks, WA 98331, United States
| | - Jonathan R Deeds
- Center for Food Safety and Applied Nutrition, Office of Regulatory Science, U.S. Food and Drug Administration, 5001 Campus Drive, College Park, Maryland, 20740, United States of America
| | - Urban Tillmann
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Section Ecological Chemistry, Am Handelshafen 12, Bremerhaven, 27570, Germany.
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Boente-Juncal A, Raposo-García S, Louzao MC, Vale C, Botana LM. Targeting Chloride Ion Channels: New Insights into the Mechanism of Action of the Marine Toxin Azaspiracid. Chem Res Toxicol 2021; 34:865-879. [PMID: 33512997 DOI: 10.1021/acs.chemrestox.0c00494] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Azaspiracids (AZAs) are marine toxins produced by dinoflagellates belonging to the genera Azadinium and Amphidoma that caused human intoxications after consumption of contaminated fishery products, such as mussels. However, the exact mechanism for the AZA induced cytotoxic and neurotoxic effects is still unknown. In this study several pharmacological approaches were employed to evaluate the role of anion channels on the AZA effects that demonstrated that cellular anion dysregulation was involved in the toxic effects of these compounds. The results presented here demonstrated that volume regulated anion channels (VRACs) are affected by this group of toxins, and, because there is not any specific activator of VRACs besides the intracellular application of GTPγ-S molecule, this group of natural compounds could represent a powerful tool to analyze the role of these channels in cellular homeostasis. In addition to this, in this work, a detailed pharmacological approach was performed in order to elucidate the anion channels present in human HEK293 cells as well as their regulation by the marine toxins azaspiracids. Altogether, the data presented here demonstrated that the effect of azaspiracids in human cells was completely dependent on ATP-regulated anion channels, whose upregulation by these toxins could lead to regulatory volume decrease and underlie the reported toxicity of these compounds.
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Affiliation(s)
- Andrea Boente-Juncal
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario s/n, 27002 Lugo, España
| | - Sandra Raposo-García
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario s/n, 27002 Lugo, España
| | - M Carmen Louzao
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario s/n, 27002 Lugo, España
| | - Carmen Vale
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario s/n, 27002 Lugo, España
| | - Luis M Botana
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario s/n, 27002 Lugo, España
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Gao J, Zhang H, Xiong P, Yan X, Liao C, Jiang G. Application of electrophysiological technique in toxicological study: From manual to automated patch-clamp recording. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2020.116082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Azaspiracids Increase Mitochondrial Dehydrogenases Activity in Hepatocytes: Involvement of Potassium and Chloride Ions. Mar Drugs 2019; 17:md17050276. [PMID: 31072021 PMCID: PMC6562809 DOI: 10.3390/md17050276] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 04/29/2019] [Accepted: 05/06/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Azaspiracids (AZAs) are marine toxins that are produced by Azadinium and Amphidoma dinoflagellates that can contaminate edible shellfish inducing a foodborne poisoning in humans, which is characterized by gastrointestinal symptoms. Among these, AZA1, -2, and -3 are regulated in the European Union, being the most important in terms of occurrence and toxicity. In vivo studies in mice showed that, in addition to gastrointestinal effects, AZA1 induces liver alterations that are visible as a swollen organ, with the presence of hepatocellular fat droplets and vacuoles. Hence, an in vitro study was carried out to investigate the effects of AZA1, -2, and -3 on liver cells, using human non-tumor IHH hepatocytes. RESULTS The exposure of IHH cells to AZA1, -2, or -3 (5 × 10-12-1 × 10-7 M) for 24 h did not affect the cell viability and proliferation (Sulforhodamine B assay and 3H-Thymidine incorporation assay), but they induced a significant concentration-dependent increase of mitochondrial dehydrogenases activity (MTT reduction assay). This effect depends on the activity of mitochondrial electron transport chain complex I and II, being counteracted by rotenone and tenoyl trifluoroacetone, respectively. Furthermore, AZAs-increased mitochondrial dehydrogenase activity was almost totally suppressed in the K+-, Cl--, and Na+-free media and sensitive to the specific inhibitors of KATP and hERG potassium channels, Na+/K+, ATPase, and cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels. CONCLUSIONS These results suggest that AZA mitochondrial effects in hepatocytes derive from an imbalance of intracellular levels of K+ and, in particular, Cl- ions, as demonstrated by the selective reduction of toxin effects by CFTR chloride channel inhibition.
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Schirone M, Berti M, Visciano P, Chiumiento F, Migliorati G, Tofalo R, Suzzi G, Di Giacinto F, Ferri N. Determination of Lipophilic Marine Biotoxins in Mussels Harvested from the Adriatic Sea by LC-MS/MS. Front Microbiol 2018; 9:152. [PMID: 29487576 PMCID: PMC5816572 DOI: 10.3389/fmicb.2018.00152] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 01/23/2018] [Indexed: 11/13/2022] Open
Abstract
Lipophilic marine biotoxins include okadaic acid, pectenotoxin, yessotoxin and azaspiracid groups. The consumption of contaminated molluscs can lead to acute food poisoning syndromes depending on the exposure level. Regulatory limits have been set by Regulation (European Community, 2004a) No 853/2004 and LC-MS/MS is used as the official analytical method according to Regulation (European Community, 2011) No 15/2011. In this study specimens of mussels (Mytilus galloprovincialis) were collected along the coasts of the central Adriatic Sea during the years 2015–2017 and analyzed by the European harmonized Standard Operating Procedure. The method was validated for linearity, specificity, repeatability and reproducibility and it revealed able to be used for the detection of the lipophilic marine biotoxins. Levels of okadaic acid, pectenotoxin, yessotoxin and its analogs were detected at different concentrations in 148 (37%) out of a total of 400 samples, always below the maximum limits, except for 11 (4.3%) of them that were non-compliant because they exceeded the regulatory limit. Moreover, some samples were exposed to a multi-toxin mixture with regards to okadaic acid, yessotoxin and 1-Homo yessotoxin. Following these results, the aquaculture farms from which the non-compliant samples derived were closed until the analytical data of two consecutive samplings returned favorable. Besides the potential risk of consumption of mussels contaminated by lipophilic marine biotoxins, these marine organisms can be considered as bio-indicators of the contamination status of the marine ecosystem.
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Affiliation(s)
- Maria Schirone
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Teramo, Italy
| | - Miriam Berti
- Biologia delle Acque Interne, Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
| | - Pierina Visciano
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Teramo, Italy
| | - Francesco Chiumiento
- Bromatologia e Residui negli Alimenti per l'Uomo e gli Animali, Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
| | - Giacomo Migliorati
- Bromatologia e Residui negli Alimenti per l'Uomo e gli Animali, Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
| | - Rosanna Tofalo
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Teramo, Italy
| | - Giovanna Suzzi
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Teramo, Italy
| | - Federica Di Giacinto
- Biologia delle Acque Interne, Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
| | - Nicola Ferri
- Biologia delle Acque Interne, Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
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Toxic equivalency factors (TEFs) after acute oral exposure of azaspiracid 1, -2 and -3 in mice. Toxicol Lett 2017; 282:136-146. [PMID: 29107028 DOI: 10.1016/j.toxlet.2017.10.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 10/18/2017] [Accepted: 10/25/2017] [Indexed: 11/22/2022]
Abstract
Azaspiracids (AZAs) are marine algal toxins that can be accumulated by edible shellfish to cause a foodborne gastrointestinal poisoning in humans. In the European Union, only AZA1, -2 and -3 are currently regulated and their concentration in shellfish is determined through their toxic equivalency factors (TEFs) derived from the intraperitoneal lethal potency in mice. Nevertheless, considering the potential human exposure by oral route, AZAs TEFs should be calculated by comparative oral toxicity data. Thus, the acute oral toxicity of AZA1, -2 and -3 was investigated in female CD-1 mice treated with different doses (AZA1: 135-1100μg/kg; AZA2 and AZA3: 300-1100μg/kg) and sacrificed after 24h or 14days. TEFs derived from the median lethal doses (LD50) were 1.0, 0.7 and 0.5, respectively for AZA1, -2 and -3. In fact, after 24h from gavage administration, LD50s were 443μg/kg (AZA1; 95% CL: 350-561μg/kg), 626μg/kg (AZA2; 95% CL: 430-911μg/kg) and 875μg/kg (AZA3; 95% CL: 757-1010μg/kg). Mice dead more than 5h after the treatment or those sacrificed after 24h (doses: ≥175μg AZA1/kg, ≥500μg AZA2/kg and ≥600μg AZA3/kg) showed enlarged pale liver, while increased serum markers of liver alteration were recorded even at the lowest doses. Blood chemistry revealed significantly increased serum levels of K+ ions (≥500mg/kg), whereas light microscopy showed tissue changes in the gastrointestinal tract, liver and spleen. No lethality, macroscopic, tissue or haematological changes were recorded two weeks post exposure, indicating reversible toxic effects. LC-MS/MS analysis of the main organs showed a dose-dependency in gastrointestinal absorption of these toxins: at 24h, the highest levels were detected in the stomach and, in descending order, in the intestinal content, liver, small intestine, kidneys, lungs, large intestine, heart as well as detectable traces in the brain. After 14days, AZA1 and AZA2 were still detectable in almost all the organs and intestinal content.
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In vivo cardiomyocyte response to YTX- and AZA-1-induced damage: autophagy versus apoptosis. Arch Toxicol 2016; 91:1859-1870. [DOI: 10.1007/s00204-016-1862-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 09/28/2016] [Indexed: 10/20/2022]
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Doerr B, O'Halloran J, O'Brien N, van Pelt F. Investigation of the genotoxic potential of the marine biotoxins azaspiracid 1-3. Toxicon 2016; 121:61-69. [PMID: 27576062 DOI: 10.1016/j.toxicon.2016.08.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/19/2016] [Accepted: 08/25/2016] [Indexed: 11/26/2022]
Abstract
Azaspiracids (AZAs) are the most recently discovered group of biotoxins and are the cause of azaspiracid shellfish poisoning (AZP) in humans. To date over thirty analogues have been identified. However, toxicological studies of AZAs are limited due to the lack of availability of toxins and toxin standards. Most data available are on acute toxicity and there are no data available on genotoxicity of AZAs. This study presents an integrated approach investigating the genotoxic potential of AZA1-3 in cell culture systems using the Comet assay combined with assays to provide information on possible apoptotic processes, cytotoxicity and changes in cell number. Results demonstrate a time and dose dependent increase in DNA fragmentation in most cell lines, indicating a genotoxic effect of AZA1-3. However, a significant reduction in cell number and a clear shift from early to late apoptosis was observed for all analogues in Jurkat T cells and HepG-2 cells; CaCo-2 cells did not show a clear apoptotic profile. Late apoptotic/necrotic cells correlate well with the percentage of tail DNA for all analogues in all three cell lines. All data taken together indicate that AZA1-3 is not genotoxic per se and demonstrate apoptotic/necrotic processes to be involved to some extent in AZAs toxicity. The sensitivities of cell lines and the different potencies of AZA1-3 are in agreement with the literature available. The order of sensitivity for all three AZAs tested in the present study is, in increasing order, CaCo-2 cells < HepG-2 cells < Jurkat T cells. The order of potency of AZA1-3 varies among the cell lines.
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Affiliation(s)
- Barbara Doerr
- Department of Pharmacology and Therapeutics, University College Cork, Cork, Ireland; Environmental Research Institute, University College Cork, Cork, Ireland.
| | - John O'Halloran
- Environmental Research Institute, University College Cork, Cork, Ireland; School of Biological, Earth and Environmental Sciences, University College Cork, Cork, Ireland.
| | - Nora O'Brien
- School of Food and Nutritional Sciences, University College Cork, Cork, Ireland.
| | - Frank van Pelt
- Department of Pharmacology and Therapeutics, University College Cork, Cork, Ireland; Environmental Research Institute, University College Cork, Cork, Ireland.
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Ferreiro SF, Vilariño N, Carrera C, Louzao MC, Cantalapiedra AG, Santamarina G, Cifuentes JM, Vieira AC, Botana LM. Subacute Cardiotoxicity of Yessotoxin: In Vitro and in Vivo Studies. Chem Res Toxicol 2016; 29:981-90. [PMID: 27104637 DOI: 10.1021/acs.chemrestox.6b00012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Yessotoxin (YTX) is a marine phycotoxin produced by dinoflagellates and accumulated in filter feeding shellfish. Although no human intoxication episodes have been reported, YTX content in shellfish is regulated by many food safety authorities due to their worldwide distribution. YTXs have been related to ultrastructural heart damage in vivo, but the functional consequences in the long term have not been evaluated. In this study, we explored the accumulative cardiotoxic potential of YTX in vitro and in vivo. Preliminary in vitro evaluation of cardiotoxicity was based on the effect on hERG (human ether-a-go-go related gene) channel trafficking. In vivo experiments were performed in rats that received repeated administrations of YTX followed by recordings of electrocardiograms, arterial blood pressure, plasmatic cardiac biomarkers, and analysis of myocardium structure and ultrastructure. Our results showed that an exposure to 100 nM YTX for 12 or 24 h caused an increase of extracellular surface hERG channels. Furthermore, remarkable bradycardia and hypotension, structural heart alterations, and increased plasma levels of tissue inhibitor of metalloproteinases-1 were observed in rats after four intraperitoneal injections of YTX at doses of 50 or 70 μg/kg that were administered every 4 days along a period of 15 days. Therefore, and for the first time, YTX-induced subacute cardiotoxicity is supported by evidence of cardiovascular function alterations related to its repeated administration. Considering international criteria for marine toxin risk estimation and that the regulatory limit for YTX has been recently raised in many countries, YTX cardiotoxicity might pose a health risk to humans and especially to people with previous cardiovascular risk.
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Affiliation(s)
- Sara F Ferreiro
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - Natalia Vilariño
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - Cristina Carrera
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - M Carmen Louzao
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - Antonio G Cantalapiedra
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - Germán Santamarina
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - J Manuel Cifuentes
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - Andrés C Vieira
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
| | - Luis M Botana
- Departamento de Farmacología, ‡Departamento de Ciencias Clínicas Veterinarias, §Hospital Veterinario Universitario Rof Codina and ∥Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidade de Santiago de Compostela , 27002 Lugo, Spain
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Ferreiro SF, Vilariño N, Carrera C, Louzao MC, Cantalapiedra AG, Santamarina G, Cifuentes JM, Vieira AC, Botana LM. Subacute Cardiovascular Toxicity of the Marine Phycotoxin Azaspiracid-1 in Rats. Toxicol Sci 2016; 151:104-14. [PMID: 26865666 DOI: 10.1093/toxsci/kfw025] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Azaspiracids (AZAs) are marine toxins produced by Azadinium spinosum that get accumulated in filter feeding shellfish through the food-web. The first intoxication was described in The Netherlands in 1990, and since then several episodes have been reported worldwide. Azaspiracid-1, AZA-2, and AZA-3 presence in shellfish is regulated by food safety authorities of several countries to protect human health. Azaspiracids have been related to widespread organ damage, tumorogenic properties and acute heart rhythm alterations in vivo but the mechanism of action remains unknown. Azaspiracid toxicity kinetics in vivo and in vitro suggests accumulative effects. We studied subacute cardiotoxicity in vivo after repeated exposure to AZA-1 by evaluation of the ECG, arterial blood pressure, plasmatic heart damage biomarkers, and myocardium structure and ultrastructure. Our results showed that four administrations of AZA-1 along 15 days caused functional signs of heart failure and structural heart alterations in rats at doses ranging from 1 to 55 µg/kg. Azaspiracid-1 altered arterial blood pressure, tissue inhibitors of metalloproteinase-1 plasma levels, heart collagen deposition, and ultrastructure of the myocardium. Overall, these data indicate that repeated exposure to low amounts of AZA-1 causes cardiotoxicity, at doses that do not induce signs of other organic system toxicity. Remarkably, human exposure to AZAs considering current regulatory limits of these toxins may be dangerously close to clearly cardiotoxic doses in rats. These findings should be considered when human risk is estimated particularly in high cardiovascular risk subpopulations.
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Affiliation(s)
| | | | - Cristina Carrera
- *Departamento de Farmacología Hospital Veterinario Universitario Rof Codina
| | | | - Antonio G Cantalapiedra
- Hospital Veterinario Universitario Rof Codina Departamento de Ciencias Clínicas Veterinarias
| | - Germán Santamarina
- Hospital Veterinario Universitario Rof Codina Departamento de Ciencias Clínicas Veterinarias
| | - J Manuel Cifuentes
- Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain
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