1
|
Nederlof RA, van der Veen D, Perrault JR, Bast R, Barron HW, Bakker J. Emerging Insights into Brevetoxicosis in Sea Turtles. Animals (Basel) 2024; 14:991. [PMID: 38612230 PMCID: PMC11010821 DOI: 10.3390/ani14070991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
This review summarizes the current understanding of how brevetoxins, produced by Karenia brevis during harmful algal blooms, impact sea turtle health. Sea turtles may be exposed to brevetoxins through ingestion, inhalation, maternal transfer, and potentially absorption through the skin. Brevetoxins bind to voltage-gated sodium channels in the central nervous system, disrupting cellular function and inducing neurological symptoms in affected sea turtles. Moreover, the current evidence suggests a broader and longer-term impact on sea turtle health beyond what is seen during stranding events. Diagnosis relies on the detection of brevetoxins in tissues and plasma from stranded turtles. The current treatment of choice, intravenous lipid emulsion therapy, may rapidly reduce symptoms and brevetoxin concentrations, improving survival rates. Monitoring, prevention, and control strategies for harmful algal blooms are discussed. However, as the frequency and severity of blooms are expected to increase due to climate change and increased environmental pollution, continued research is needed to better understand the sublethal effects of brevetoxins on sea turtles and the impact on hatchlings, as well as the pharmacokinetic mechanisms underlying brevetoxicosis. Moreover, research into the optimization of treatments may help to protect endangered sea turtle populations in the face of this growing threat.
Collapse
Affiliation(s)
| | | | - Justin R. Perrault
- Loggerhead Marinelife Center, Juno Beach, FL 33408, USA; (J.R.P.); (H.W.B.)
| | - Robin Bast
- Clinic for the Rehabilitation of Wildlife, Inc., Sanibel, FL 33957, USA;
| | - Heather W. Barron
- Loggerhead Marinelife Center, Juno Beach, FL 33408, USA; (J.R.P.); (H.W.B.)
| | - Jaco Bakker
- Animal Science Department, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands;
| |
Collapse
|
2
|
Jobson J, Tsegay PS, Beltran MT, Taher EA, Rein SR, Liu Y, Rein KS. Brevetoxin induces a shift in the redox state of the proteome and unfolded protein response in human lymphoblast cells that can be alleviated with the acrolein scavenger MESNA. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 100:104137. [PMID: 37127110 DOI: 10.1016/j.etap.2023.104137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 04/24/2023] [Accepted: 04/29/2023] [Indexed: 05/03/2023]
Abstract
Human lymphoblast cells were treated with the marine algal toxin, brevetoxin-2 (PbTx-2), and its effects on the proteome were assessed by redox proteomics using cysteine reactive tandem mass tags (TMT). Additionally, cells were simultaneously treated with PbTx-2 and the antioxidant and acrolein scavenger sodium 2-mercaptoethylsulfonate (MESNA) to determine if MESNA could prevent the proteomic effects of brevetoxin-2. A massive shift in the redox state of the proteome of brevetoxin-2 treated cells was observed. The main pathway affected was genetic information processing. Significantly oxidized proteins included Trx-1, peroxyredoxins (Prxs), ribosomal proteins, and the eukaryotic initiation factor 2 β subunit (eIF2β). Proteins that were overexpressed in brevetoxin-treated cells included four folding chaperones. These effects were diminished in the presence of MESNA indicating that MESNA may act through its antioxidant properties or as a brevetoxin scavenger. These studies provide novel insights into new prophylactics for brevetoxicosis in humans and wildlife.
Collapse
Affiliation(s)
- Jordan Jobson
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Pawlos S Tsegay
- Biochemistry Ph.D. Program, Florida International University, Miami, FL 33199, USA
| | - Mayra Tabares Beltran
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Eman A Taher
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Samuel R Rein
- The School District of Philadelphia, Philadelphia, PA 19130, USA
| | - Yuan Liu
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; Biochemistry Ph.D. Program, Florida International University, Miami, FL 33199, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Kathleen S Rein
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; Current address: The Water School, Department of Marine and Earth Science and Department of Chemistry and Physics, Florida Gulf Coast University, Fort Myers, FL 33965.
| |
Collapse
|
3
|
Brammer-Robbins E, Costa KA, Bowden JA, Martyniuk CJ, Larkin IV, Denslow ND. Putative high-level toxicity pathways based on evidence of brevetoxin immunotoxicity in marine fauna. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 252:106298. [PMID: 36162204 DOI: 10.1016/j.aquatox.2022.106298] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 08/25/2022] [Accepted: 09/10/2022] [Indexed: 06/16/2023]
Abstract
Red tide events, caused by a toxin producing dinoflagellate, Karenia brevis, occur annually in Florida and Texas. These events lead to health risks for both humans and wildlife that utilize coastal environments. Brevetoxins, potent lipophilic neurotoxins produced by K. brevis, modulate immune responses in laboratory studies with model organisms and in the natural environment in both humans and wildlife. Studies show that brevetoxins activate immune cells, stimulate production of gamma-globulins, cytokines, and neutrophils, modulate lysozyme activity, induce apoptosis, and modulate lymphocyte proliferation in marine species. The objective of this review was to summarize brevetoxin-induced immunotoxicity in marine animals based on available peer-reviewed literature about K. brevis blooms and associated health concerns and propose putative toxicity pathways. This review identifies knowledge gaps within current brevetoxin induced immunotoxicity research, including assessing the long-term impacts of brevetoxin exposure, elucidating the mechanistic linkages between brevetoxins and immune cells, and evaluating repeated and chronic versus acute brevetoxin exposure implications on overall organismal health. The putative immunotoxicity pathways based on evidence from brevetoxin-exposure in marine fauna described in this review represent a useful tool and resource for researchers, wildlife managers, and policy makers. This review and proposed putative immunotoxicity pathways will inform decisions regarding the risks of algal blooms, as it pertains to marine animal health.
Collapse
Affiliation(s)
- Elizabeth Brammer-Robbins
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32611, United States; Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611, United States
| | - Kaylie Anne Costa
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32611, United States
| | - John A Bowden
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32611, United States; Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611, United States
| | - Christopher J Martyniuk
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32611, United States; Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611, United States
| | - Iske V Larkin
- Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610, United States
| | - Nancy D Denslow
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32611, United States; Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611, United States.
| |
Collapse
|
4
|
Annunziato M, Eeza MNH, Bashirova N, Lawson A, Matysik J, Benetti D, Grosell M, Stieglitz JD, Alia A, Berry JP. An integrated systems-level model of the toxicity of brevetoxin based on high-resolution magic-angle spinning nuclear magnetic resonance (HRMAS NMR) metabolic profiling of zebrafish embryos. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 803:149858. [PMID: 34482148 DOI: 10.1016/j.scitotenv.2021.149858] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
Brevetoxins (PbTx) are a well-recognized group of neurotoxins associated with harmful algal blooms, and specifically recurrent "Florida Red Tides," in marine waters that are linked to impacts on both human and ecosystem health including well-documented "fish kills" and marine mammal mortalities in affected coastal waters. Understanding mechanisms and pathways of PbTx toxicity enables identification of relevant biomarkers to better understand these environmental impacts, and improve monitoring efforts, in relation to this toxin. Toward a systems-level understanding of toxicity, and identification of potential biomarkers, high-resolution magic angle spinning nuclear magnetic resonance (HRMAS NMR) was utilized for metabolic profiling of zebrafish (Danio rerio) embryos, as an established toxicological model, exposed to PbTx-2 (the most common congener in marine waters). Metabolomics studies were, furthermore, complemented by an assessment of the toxicity of PbTx-2 in embryonic stages of zebrafish and mahi-mahi (Coryphaena hippurus), the latter representing an ecologically and geographically relevant marine species of fish, which identified acute embryotoxicity at environmentally relevant (i.e., parts-per-billion) concentrations in both species. HRMAS NMR analysis of intact zebrafish embryos exposed to sub-lethal concentrations of PbTx-2 afforded well-resolved spectra, and in turn, identification of 38 metabolites of which 28 were found to be significantly altered, relative to controls. Metabolites altered by PbTx-2 exposure specifically included those associated with (1) neuronal excitotoxicity, as well as associated neural homeostasis, and (2) interrelated pathways of carbohydrate and energy metabolism. Metabolomics studies, thereby, enabled a systems-level model of PbTx toxicity which integrated multiple metabolic, molecular and cellular pathways, in relation to environmentally relevant concentrations of the toxin, providing insight to not only targets and mechanisms, but potential biomarkers pertinent to environmental risk assessment and monitoring strategies.
Collapse
Affiliation(s)
- Mark Annunziato
- Institute of Environment, Department of Chemistry and Biochemistry, Florida International University, 3000 NE 151st Street, North Miami, FL 33181, USA
| | - Muhamed N H Eeza
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany; Institute for Analytical Chemistry, University of Leipzig, Leipzig, Germany
| | - Narmin Bashirova
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany; Institute for Analytical Chemistry, University of Leipzig, Leipzig, Germany
| | - Ariel Lawson
- Institute of Environment, Department of Chemistry and Biochemistry, Florida International University, 3000 NE 151st Street, North Miami, FL 33181, USA
| | - Jörg Matysik
- Institute for Analytical Chemistry, University of Leipzig, Leipzig, Germany
| | - Daniel Benetti
- Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA
| | - Martin Grosell
- Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA
| | - John D Stieglitz
- Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA
| | - A Alia
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany; Leiden Institute of Chemistry, Leiden University, 2333 Leiden, the Netherlands.
| | - John P Berry
- Institute of Environment, Department of Chemistry and Biochemistry, Florida International University, 3000 NE 151st Street, North Miami, FL 33181, USA; Biomolecular Science Institute, Florida International University, 11200 SW 8th Street, Miami, FL 33199, USA.
| |
Collapse
|
5
|
Walsh CJ, Cocilova C, Restivo J, Flewelling L, Milton S. Immune function in Trachemys scripta following exposure to a predominant brevetoxin congener, PbTx-3, as a model for potential health impacts for sea turtles naturally exposed to brevetoxins. ECOTOXICOLOGY (LONDON, ENGLAND) 2019; 28:1085-1104. [PMID: 31559558 DOI: 10.1007/s10646-019-02110-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/09/2019] [Indexed: 06/10/2023]
Abstract
Many species of marine life in southwestern Florida, including sea turtles, are impacted by blooms of the toxic dinoflagellate, Karenia brevis. Sublethal exposure to toxins produced by K. brevis has been shown to impact sea turtle health. Since all sea turtles in the Gulf of Mexico have protected status, a freshwater turtle, Trachemys scripta, was used as a model for immune system effects following experimental exposure to a predominant brevetoxin congener in K. brevis blooms, PbTx-3. Exposure to PbTx-3 was oral or intratracheal and health effects were assessed using a suite of immune function parameters: innate immune function (phagocytosis, plasma lysozyme activity), adaptive immune function (lymphocyte proliferation), and measures of oxidative stress (superoxide dismutase (SOD) and glutathione-S-transferase (GST) activity in plasma). Inflammation was also measured using plasma protein electrophoresis. In addition, differential expression of genes in peripheral blood leukocytes was determined using suppression subtractive hybridization followed by real-time PCR of specific genes. The primary immune effects of sublethal brevetoxin exposure in T. scripta following PbTx-3 administration, appear to be an increase in oxidative stress, a decrease in lysozyme activity, and modulation of immune function through lymphocyte proliferation responses. Plasma protein electrophoresis showed a decreased A:G ratio which may indicate potential inflammation. Genes coding for oxidative stress, such as thioredoxin and GST, were upregulated in exposed animals. That sublethal brevetoxin exposures impact immune function components suggests potential health implications for sea turtles naturally exposed to toxins. Knowledge of physiological stressors induced by brevetoxins may contribute to the ultimate goal of developing directed treatment strategies in exposed animals for reduced mortality resulting from red tide toxin exposure in sea turtles.
Collapse
Affiliation(s)
- Catherine J Walsh
- Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA.
| | - Courtney Cocilova
- Florida Atlantic University, 777 Glades Road, Boca Raton, FL, 33431, USA
| | - Jessica Restivo
- Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA
| | - Leanne Flewelling
- Florida Fish and Wildlife Conservation Commission, 100 8th Ave SE, St. Petersburg, FL, 33701, USA
| | - Sarah Milton
- Florida Atlantic University, 777 Glades Road, Boca Raton, FL, 33431, USA
| |
Collapse
|
6
|
Tuladhar A, Hondal RJ, Colon R, Hernandez EL, Rein KS. Effectors of thioredoxin reductase: Brevetoxins and manumycin-A. Comp Biochem Physiol C Toxicol Pharmacol 2019; 217:76-86. [PMID: 30476593 PMCID: PMC7485175 DOI: 10.1016/j.cbpc.2018.11.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 11/21/2018] [Indexed: 02/03/2023]
Abstract
The activities of two effectors, brevetoxin (PbTx) and manumycin-A (Man-A), of thioredoxin reductase (TrxR) have been evaluated against a series of fourteen TrxR orthologs originating from mammals, insects and protists and several mutants. Man-A, a molecule with numerous electrophilic sites, forms a covalent adduct with most selenocystine (Sec)-containing TrxR enzymes. The evidence also demonstrates that Man-A can form covalent adducts with some non-Sec-containing enzymes. The activities of TrxR enzymes towards various substrates are moderated by Man-A either positively or negatively depending on the enzyme. In general, the reduction of substrates by Sec-containing TrxR is inhibited and NADPH oxidase activity is activated. For non-Sec-containing TrxR the effect of Man-A on the reduction of substrates is variable, but NADPH oxidase activity can be activated even in the absence of covalent modification of TrxR. The effect of PbTx is less pronounced. A smaller subset of enzymes is affected by PbTx. With a single exception, the activities of most of this subset are activated. Although both PbTx variants can react with selenocysteine, a stable covalent adduct is not formed with any of the TrxR enzymes. The key findings from this work are (i) the identification of an alternate mechanism of toxicity for the algal toxin brevetoxin (ii) the demonstration that covalent modification of TrxR is not a prerequisite for the activation of NADPH oxidase activity of TrxR and (iii) the identification of an inhibitor which can discriminate between cytosolic and mitochondrial TrxR.
Collapse
Affiliation(s)
- Anupama Tuladhar
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Robert J Hondal
- Department of Biochemistry, 89 Beaumont Ave, Given Building Room 413B, Burlington, VT 05405, United States
| | - Ricardo Colon
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Elyssa L Hernandez
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Kathleen S Rein
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States.
| |
Collapse
|
7
|
J Kramer B, J Bourdelais A, Kitchen SA, Taylor AR. Uptake and localization of fluorescently-labeled Karenia brevis metabolites in non-toxic marine microbial taxa. JOURNAL OF PHYCOLOGY 2019; 55:47-59. [PMID: 30239000 DOI: 10.1111/jpy.12787] [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: 02/25/2018] [Accepted: 06/21/2018] [Indexed: 06/08/2023]
Abstract
Brevetoxin (PbTx) is a neurotoxic secondary metabolite of the dinoflagellate Karenia brevis. We used a novel, fluorescent BODIPY-labeled conjugate of brevetoxin congener PbTx-2 (B-PbTx) to track absorption of the metabolite into a variety of marine microbes. The labeled toxin was taken up and brightly fluoresced in lipid-rich regions of several marine microbes including diatoms and coccolithophores. The microzooplankton (20-200 μm) tintinnid ciliate Favella sp. and the rotifer Brachionus rotundiformis also took up B-PbTx. Uptake and intracellular fluorescence of B-PbTx was weak or undetectable in phytoplankton species representative of dinoflagellates, cryptophytes, and cyanobacteria over the same (4 h) time course. The cellular fate of two additional BODIPY-conjugated K. brevis associated secondary metabolites, brevenal (B-Bn) and brevisin (B-Bs), were examined in all the species tested. All taxa exhibited minimal or undetectable fluorescence when exposed to the former conjugate, while most brightly fluoresced when treated with the latter. This is the first study to observe the uptake of fluorescently-tagged brevetoxin conjugates in non-toxic phytoplankton and zooplankton taxa, demonstrating their potential in investigating whether marine microbes can serve as a significant biological sink for algal toxins. The highly variable uptake of B-PbTx observed among taxa suggests some may play a more significant role than others in vectoring lipophilic toxins in the marine environment.
Collapse
Affiliation(s)
- Benjamin J Kramer
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, USA
| | - Andrea J Bourdelais
- MARBIONC, CREST Research Park, University of North Carolina Wilmington, Wilmington, North Carolina, USA
| | - Sheila A Kitchen
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, USA
| | - Alison R Taylor
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, USA
| |
Collapse
|
8
|
Chen W, Tuladhar A, Rolle S, Lai Y, Rodriguez Del Rey F, Zavala CE, Liu Y, Rein KS. Brevetoxin-2, is a unique inhibitor of the C-terminal redox center of mammalian thioredoxin reductase-1. Toxicol Appl Pharmacol 2017; 329:58-66. [PMID: 28551108 DOI: 10.1016/j.taap.2017.05.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 05/15/2017] [Accepted: 05/22/2017] [Indexed: 11/15/2022]
Abstract
Karenia brevis, the Florida red tide dinoflagellate produces a suite of neurotoxins known as the brevetoxins. The most abundant of the brevetoxins PbTx-2, was found to inhibit the thioredoxin-thioredoxin reductase system, whereas the PbTx-3 has no effect on this system. On the other hand, PbTx-2 activates the reduction of small disulfides such as 5,5'-dithio-bis-(2-nitrobenzoic acid) by thioredoxin reductase. PbTx-2 has an α, β-unsaturated aldehyde moiety which functions as an efficient electrophile and selenocysteine conjugates are readily formed. PbTx-2 blocks the inhibition of TrxR by the inhibitor curcumin, whereas curcumin blocks PbTx-2 activation of TrxR. It is proposed that the mechanism of inhibition of thioredoxin reduction is via the formation of a Michael adduct between selenocysteine and the α, β-unsaturated aldehyde moiety of PbTx-2. PbTx-2 had no effect on the rates of reactions catalyzed by related enzymes such as glutathione reductase, glutathione peroxidase or glutaredoxin.
Collapse
Affiliation(s)
- Wei Chen
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Anupama Tuladhar
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Shantelle Rolle
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Yanhao Lai
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Freddy Rodriguez Del Rey
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Cristian E Zavala
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Yuan Liu
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States; Biomolecular Sciences Institute, School of Integrated Sciences and Humanity, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States
| | - Kathleen S Rein
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, United States.
| |
Collapse
|
9
|
Walsh CJ, Butawan M, Yordy J, Ball R, Flewelling L, de Wit M, Bonde RK. Sublethal red tide toxin exposure in free-ranging manatees (Trichechus manatus) affects the immune system through reduced lymphocyte proliferation responses, inflammation, and oxidative stress. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 161:73-84. [PMID: 25678466 DOI: 10.1016/j.aquatox.2015.01.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 01/20/2015] [Accepted: 01/21/2015] [Indexed: 06/04/2023]
Abstract
The health of many Florida manatees (Trichechus manatus latirostris) is adversely affected by exposure to blooms of the toxic dinoflagellate, Karenia brevis. K. brevis blooms are common in manatee habitats of Florida's southwestern coast and produce a group of cyclic polyether toxins collectively referred to as red tide toxins, or brevetoxins. Although a large number of manatees exposed to significant levels of red tide toxins die, several manatees are rescued from sublethal exposure and are successfully treated and returned to the wild. Sublethal brevetoxin exposure may potentially impact the manatee immune system. Lymphocyte proliferative responses and a suite of immune function parameters in the plasma were used to evaluate effects of brevetoxin exposure on health of manatees rescued from natural exposure to red tide toxins in their habitat. Blood samples were collected from rescued manatees at Lowry Park Zoo in Tampa, FL and from healthy, unexposed manatees in Crystal River, FL. Peripheral blood leukocytes (PBL) isolated from whole blood were stimulated with T-cell mitogens, ConA and PHA. A suite of plasma parameters, including plasma protein electrophoresis profiles, lysozyme activity, superoxide dismutase (SOD) activity, and reactive oxygen/nitrogen (ROS/RNS) species, was also used to assess manatee health. Significant decreases (p<0.05) in lymphocyte proliferation were observed in ConA and PHA stimulated lymphocytes from rescued animals compared to non-exposed animals. Significant correlations were observed between oxidative stress markers (SOD, ROS/RNS) and plasma brevetoxin concentrations. Sublethal exposure to brevetoxins in the wild impacts some immune function components, and thus, overall health, in the Florida manatee.
Collapse
Affiliation(s)
- Catherine J Walsh
- Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA.
| | - Matthew Butawan
- Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA.
| | - Jennifer Yordy
- Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA.
| | - Ray Ball
- Lowry Park Zoo, 1101 W Sligh Ave, Tampa, FL 33604, USA.
| | - Leanne Flewelling
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, 100 8th Ave SE, St. Petersburg, FL 33701, USA.
| | - Martine de Wit
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, 100 8th Ave SE, St. Petersburg, FL 33701, USA.
| | - Robert K Bonde
- U.S. Geological Survey, Sirenia Project, 7920 NE 71st Street, Gainesville, FL 32653, USA.
| |
Collapse
|
10
|
Fleming LE, Kirkpatrick B, Backer LC, Walsh CJ, Nierenberg K, Clark J, Reich A, Hollenbeck J, Benson J, Cheng YS, Naar J, Pierce R, Bourdelais AJ, Abraham WM, Kirkpatrick G, Zaias J, Wanner A, Mendes E, Shalat S, Hoagland P, Stephan W, Bean J, Watkins S, Clarke T, Byrne M, Baden DG. Review of Florida Red Tide and Human Health Effects. HARMFUL ALGAE 2011; 10:224-233. [PMID: 21218152 PMCID: PMC3014608 DOI: 10.1016/j.hal.2010.08.006] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
This paper reviews the literature describing research performed over the past decade on the known and possible exposures and human health effects associated with Florida red tides. These harmful algal blooms are caused by the dinoflagellate, Karenia brevis, and similar organisms, all of which produce a suite of natural toxins known as brevetoxins. Florida red tide research has benefited from a consistently funded, long term research program, that has allowed an interdisciplinary team of researchers to focus their attention on this specific environmental issue-one that is critically important to Gulf of Mexico and other coastal communities. This long-term interdisciplinary approach has allowed the team to engage the local community, identify measures to protect public health, take emerging technologies into the field, forge advances in natural products chemistry, and develop a valuable pharmaceutical product. The Review includes a brief discussion of the Florida red tide organisms and their toxins, and then focuses on the effects of these toxins on animals and humans, including how these effects predict what we might expect to see in exposed people.
Collapse
Affiliation(s)
- Lora E Fleming
- NSF NIEHS Oceans and Human Health Center, University of Miami, 4600 Rickenbacker Causeway, Miami, FL, 33149
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Wang Z, Ramsdell JS. Analysis of interactions of brevetoxin-B and human serum albumin by liquid chromatography/mass spectrometry. Chem Res Toxicol 2010; 24:54-64. [PMID: 21142195 DOI: 10.1021/tx1002854] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Brevetoxins are neurotoxins produced by marine dinoflagellates, primarily Karenia brevis, and can cause intoxication and even mortality of marine species, affect human health through the consumption of brevetoxin-contaminated shellfish, and effect respiratory irritation through aerosol exposure at coastal areas. Brevetoxin-A and brevetoxin-B, the major brevetoxins produced in algae, are metabolized to a series of amino acid and peptide-related derivatives in shellfish through the reactions of the amino acid residue cysteine with an α,β-unsaturated aldehyde group. In this paper, covalent interactions between brevetoxin and proteins were investigated using brevetoxin-B and human serum albumin (HSA) as a model. It is demonstrated that both noncovalent and covalent interactions can occur between brevetoxin-B and HSA with in vitro experiments. Covalent adducts of brevetoxin-B and HSA were generated under physiological conditions and reduced with sodium borohydride based on the reaction conditions of single amino acid residues with brevetoxin-B. LC/MS analysis of toxin-treated HSA recognized the formation of the intact protein adducts with primarily one and two toxin molecules attached to one HSA molecule. HSA treated with/without brevetoxin-B was digested with trypsin, trypsin following chymotrypsin, and Pronase, respectively, for LC/MS analysis of adduction sites. Brevetoxin-B was found to react primarily with Cys(34) and His(3) and with His and Lys at other sites of HSA with variable reactivity and with Lys in general the least reactive.
Collapse
Affiliation(s)
- Zhihong Wang
- Marine Biotoxins Program, Center for Coastal Environmental Health and Biomolecular Research, NOAA/National Ocean Service, 219 Fort Johnson Road, Charleston, South Carolina 29412, USA
| | | |
Collapse
|
12
|
Walsh CJ, Leggett SR, Carter BJ, Colle C. Effects of brevetoxin exposure on the immune system of loggerhead sea turtles. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2010; 97:293-303. [PMID: 20060602 DOI: 10.1016/j.aquatox.2009.12.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Revised: 12/04/2009] [Accepted: 12/12/2009] [Indexed: 05/28/2023]
Abstract
Blooms of the toxic dinoflagellate, Karenia brevis, occur almost annually off the Florida coast. These blooms, commonly called "red tides", produce a group of neurotoxins collectively termed brevetoxins. Many species of sealife, including sea turtles, are severely impacted by brevetoxin exposure. Effects of brevetoxins on immune cells were investigated in rescued loggerhead sea turtles, Caretta caretta, as well as through in vitro experiments using peripheral blood leukocytes (PBL) collected from captive sea turtles. In rescued animals, plasma brevetoxin concentrations were measured using a competitive ELISA. Plasma lysozyme activity was measured using a turbidity assay. Lysozyme activity correlated positively with plasma brevetoxin concentrations. Differential expression of genes affected by brevetoxin exposure was determined using two separate suppression subtractive hybridization experiments. In one experiment, genes from PBL collected from sea turtles rescued from red tide toxin exposure were compared to genes from PBL collected from healthy captive loggerhead sea turtles. In the second experiment, PBL from healthy captive loggerhead sea turtles were exposed to brevetoxin (500 ng PbTx-2/ml) in vitro for 18 h and compared to unexposed PBL. Results from the subtraction hybridization experiment conducted with red tide rescued sea turtle PBL indicated that genes involved in oxidative stress or xenobiotic metabolism were up-regulated. Using quantitative real-time PCR, a greater than 2-fold increase in superoxide dismutase and thioredoxin and greater than 10-fold increase in expression of thiopurine S-methyltransferase were observed. Results from the in vitro subtraction hybridization experiment indicated that genes coding for cytochrome c oxidases were the major up-regulated genes. Using quantitative real-time PCR, a greater than 8-fold increase in expression of beta-tubulin and greater than 3-fold increase in expression of ubiquinol were observed. Brevetoxin exposure may have significant implications for immune function in loggerhead sea turtles.
Collapse
Affiliation(s)
- Catherine J Walsh
- Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA.
| | | | | | | |
Collapse
|
13
|
Brevetoxin B is a clastogen in rats, but lacks mutagenic potential in the SP-98/100 Ames test. Toxicon 2009; 54:851-6. [DOI: 10.1016/j.toxicon.2009.06.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Revised: 06/12/2009] [Accepted: 06/16/2009] [Indexed: 11/18/2022]
|