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Li X, Li K, Li J, Zhang Z, Wang H. Effects of perchlorate and exogenous T4 on growth, development and tail resorption of Rana chensinensis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 335:122333. [PMID: 37558196 DOI: 10.1016/j.envpol.2023.122333] [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: 06/27/2023] [Revised: 07/31/2023] [Accepted: 08/06/2023] [Indexed: 08/11/2023]
Abstract
Endocrine disruptors have been demonstrated to exert adverse effects on growth and development of amphibians by disrupting hormone levels. Tail resorption, which is one of the most remarkable events during amphibian metamorphosis, is closely associated with thyroid hormones levels. However, limited research has been conducted on the effects of endocrine disruptors on tail resorption in amphibians. This study explored the effects of NaClO4 and T4 on the growth, development and tail resorption during the metamorphosis of Rana Chensinensis. The results demonstrated that exposure to NaClO4 led to an increase in body size and a delay in metamorphosis of R. Chensinensis tadpoles. Histological analysis revealed that both NaClO4 and exogenous T4 exposure resulted in thyroid gland injury, and NaClO4 treatment delayed the degradation of notochord and muscles, thereby delaying tail resorption. Moreover, transcriptome sequencing results showed that apoptosis-related genes (APAF1, BAX and CASP6) and cell component degradation-related genes (MMP9 and MMP13) were highly expressed in the T4 exposure group, and the expression of oxidative stress-related genes (SOD and CAT) was higher in the NaClO4 exposure group. Taken together, both NaClO4 and exogenous T4 affect tail resorption in R. Chensinensis, thereby affecting their adaptation to terrestrial life. The present study will not only provide a reference for future experimental research on the effects of other endocrine disruptors on the growth, development and tail resorption of amphibians but will also provide insights into environmental protection and ecological risk assessment.
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Affiliation(s)
- Xinyi Li
- College of Life Science, Shaanxi Normal University, Xi'an, 710119, China
| | - Kaiyue Li
- College of Life Science, Shaanxi Normal University, Xi'an, 710119, China
| | - Jiayi Li
- College of Life Science, Shaanxi Normal University, Xi'an, 710119, China
| | - Zhiqin Zhang
- Basic Experimental Teaching Center, Shaanxi Normal University, Xi'an, 710119, China
| | - Hongyuan Wang
- College of Life Science, Shaanxi Normal University, Xi'an, 710119, China.
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2
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Thambirajah AA, Wade MG, Verreault J, Buisine N, Alves VA, Langlois VS, Helbing CC. Disruption by stealth - Interference of endocrine disrupting chemicals on hormonal crosstalk with thyroid axis function in humans and other animals. ENVIRONMENTAL RESEARCH 2022; 203:111906. [PMID: 34418447 DOI: 10.1016/j.envres.2021.111906] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 08/04/2021] [Accepted: 08/16/2021] [Indexed: 06/13/2023]
Abstract
Thyroid hormones (THs) are important regulators of growth, development, and homeostasis of all vertebrates. There are many environmental contaminants that are known to disrupt TH action, yet their mechanisms are only partially understood. While the effects of Endocrine Disrupting Chemicals (EDCs) are mostly studied as "hormone system silos", the present critical review highlights the complexity of EDCs interfering with TH function through their interactions with other hormonal axes involved in reproduction, stress, and energy metabolism. The impact of EDCs on components that are shared between hormone signaling pathways or intersect between pathways can thus extend beyond the molecular ramifications to cellular, physiological, behavioral, and whole-body consequences for exposed organisms. The comparatively more extensive studies conducted in mammalian models provides encouraging support for expanded investigation and highlight the paucity of data generated in other non-mammalian vertebrate classes. As greater genomics-based resources become available across vertebrate classes, better identification and delineation of EDC effects, modes of action, and identification of effective biomarkers suitable for HPT disruption is possible. EDC-derived effects are likely to cascade into a plurality of physiological effects far more complex than the few variables tested within any research studies. The field should move towards understanding a system of hormonal systems' interactions rather than maintaining hormone system silos.
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Affiliation(s)
- Anita A Thambirajah
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Michael G Wade
- Environmental Health Science & Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada
| | - Jonathan Verreault
- Centre de Recherche en Toxicologie de l'environnement (TOXEN), Département des Sciences Biologiques, Université du Québec à Montréal, Succursale Centre-ville, Montréal, QC, H3C 3P8, Canada
| | - Nicolas Buisine
- UMR7221 Physiologie Moléculaire et Adaptation, Centre National de la Recherche Scientifique, Muséum National d'Histoire Naturelle, Paris Cedex 05, France
| | - Verônica A Alves
- Centre Eau Terre Environnement, Institut National de La Recherche Scientifique (INRS), Québec City, QC, G1K 9A9, Canada
| | - Valerie S Langlois
- Centre Eau Terre Environnement, Institut National de La Recherche Scientifique (INRS), Québec City, QC, G1K 9A9, Canada
| | - Caren C Helbing
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8P 5C2, Canada.
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3
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Liu Y, Wang H, Chai L, Li X, Wu M, Wang H. Effects of perchlorate and exogenous T4 exposures on development, metamorphosis and endochondral ossification in Bufo gargarizans larvae. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 242:106036. [PMID: 34818595 DOI: 10.1016/j.aquatox.2021.106036] [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: 05/05/2021] [Revised: 11/12/2021] [Accepted: 11/14/2021] [Indexed: 06/13/2023]
Abstract
Several endocrine-disrupting chemicals (EDCs) have been proven to interfere with the physiological function of thyroid hormone (TH), which affected growth and development. However, few studies have investigated the effects of EDCs on TH axis with consequence for skeletal development in amphibians. This study thus examined the potential role of perchlorate and T4 in growth, development and endochondral ossification during metamorphosis of Bufo gargarizans. Our studies showed that NaClO₄ treatment caused weight gain and delayed the developmental stage in B. gargarizans tadpoles, while T4 decreased body size and survival rate, accelerated metamorphic duration and increased the risk of early death. Histological sections suggested that NaClO₄ and T4 treatments caused damages to thyroid tissue, such as decreased thyroid gland size, follicle size, colloid area, the height of follicular epithelial cells and the number of follicles. In addition, the double skeletal staining and RT-qPCR showed that NaClO₄ and T4 treatments inhibited the endochondral ossification by regulating TH synthesis (TRs, Dios) and endochondral ossification-related genes (MMPs, Runxs, VEGFs and VEGFRs) expression levels, which might affect terrestrial locomotion and terrestrial life. Altogether, these thyroid injury and gene expression changes as caused by NaClO₄ and T4 may have an influence on development and endochondral ossification during the metamorphosis of amphibians.
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Affiliation(s)
- Yutian Liu
- College of Life Science, Shaanxi Normal University, Xi'an 710119, China
| | - Hemei Wang
- College of Life Science, Shaanxi Normal University, Xi'an 710119, China
| | - Lihong Chai
- School of Water and Environment, Chang'an University, Xi'an 710054, China; Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an 710062, China
| | - Xinyi Li
- College of Life Science, Shaanxi Normal University, Xi'an 710119, China
| | - Minyao Wu
- College of Life Science, Shaanxi Normal University, Xi'an 710119, China
| | - Hongyuan Wang
- College of Life Science, Shaanxi Normal University, Xi'an 710119, China.
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4
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Sarraude T, Hsu BY, Ruuskanen S, Groothuis T. Is maternal thyroid hormone deposition subject to a trade-off between self and egg because of iodine? An experimental study in rock pigeon. J Exp Biol 2021; 224:272570. [PMID: 34605889 PMCID: PMC8545739 DOI: 10.1242/jeb.242203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Accepted: 09/29/2021] [Indexed: 11/20/2022]
Abstract
Maternal hormones constitute a key signalling pathway for mothers to shape offspring phenotype and fitness. Thyroid hormones (THs; triiodothyronine, T3; and thyroxine, T4) are metabolic hormones known to play crucial roles in embryonic development and survival in all vertebrates. During early developmental stages, embryos exclusively rely on exposure to maternal THs, and maternal hypothyroidism can cause severe embryonic maldevelopment. The TH molecule includes iodine, an element that cannot be synthesised by the organism. Therefore, TH production may become costly when environmental iodine availability is low. This may yield a trade-off for breeding females between allocating the hormones to self or to their eggs, potentially to the extent that it even influences the number of laid eggs. In this study, we investigated whether low dietary iodine may limit TH production and transfer to the eggs in a captive population of rock pigeons (Columba livia). We provided breeding females with an iodine-restricted (I−) diet or iodine-supplemented (I+) diet and measured the resulting circulating and yolk iodine and TH concentrations and the number of eggs laid. Our iodine-restricted diet successfully decreased both circulating and yolk iodine concentrations compared with the supplemented diet, but not circulating or yolk THs. This indicates that mothers may not be able to independently regulate hormone exposure for self and their embryos. However, egg production was clearly reduced in the I− group, with fewer females laying eggs. This result shows that restricted availability of iodine does induce a cost in terms of egg production. Whether females reduced egg production to preserve THs for themselves or to prevent embryos from exposure to low iodine and/or THs is as yet unclear. Summary: Restricted dietary iodine in captive rock pigeons reduces egg production in some females, thus inducing a trade-off between offspring quality and offspring quantity.
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Affiliation(s)
- Tom Sarraude
- Department of Biology, University of Turku, FI-20014 Turku, Finland.,Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Bin-Yan Hsu
- Department of Biology, University of Turku, FI-20014 Turku, Finland
| | - Suvi Ruuskanen
- Department of Biology, University of Turku, FI-20014 Turku, Finland.,Department of Biological and Environmental Science, University of Jyväskylä, Seminaarinkatu 15, FI-40014, Finland
| | - Ton Groothuis
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
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Singh SK, Das D, Rhen T. Embryonic Temperature Programs Phenotype in Reptiles. Front Physiol 2020; 11:35. [PMID: 32082193 PMCID: PMC7005678 DOI: 10.3389/fphys.2020.00035] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 01/16/2020] [Indexed: 12/14/2022] Open
Abstract
Reptiles are critically affected by temperature throughout their lifespan, but especially so during early development. Temperature-induced changes in phenotype are a specific example of a broader phenomenon called phenotypic plasticity in which a single individual is able to develop different phenotypes when exposed to different environments. With climate change occurring at an unprecedented rate, it is important to study temperature effects on reptiles. For example, the potential impact of global warming is especially pronounced in species with temperature-dependent sex determination (TSD) because temperature has a direct effect on a key phenotypic (sex) and demographic (population sex ratios) trait. Reptiles with TSD also serve as models for studying temperature effects on the development of other traits that display continuous variation. Temperature directly influences metabolic and developmental rate of embryos and can have permanent effects on phenotype that last beyond the embryonic period. For instance, incubation temperature programs post-hatching hormone production and growth physiology, which can profoundly influence fitness. Here, we review current knowledge of temperature effects on phenotypic and developmental plasticity in reptiles. First, we examine the direct effect of temperature on biophysical processes, the concept of thermal performance curves, and the process of thermal acclimation. After discussing these reversible temperature effects, we focus the bulk of the review on developmental programming of phenotype by temperature during embryogenesis (i.e., permanent developmental effects). We focus on oviparous species because eggs are especially susceptible to changes in ambient temperature. We then discuss recent work probing the role of epigenetic mechanisms in mediating temperature effects on phenotype. Based on phenotypic effects of temperature, we return to the potential impact of global warming on reptiles. Finally, we highlight key areas for future research, including the identification of temperature sensors and assessment of genetic variation for thermosensitivity.
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Affiliation(s)
| | | | - Turk Rhen
- Department of Biology, University of North Dakota, Grand Forks, ND, United States
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6
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Galligan TM, Hale MD, McCoy JA, Bermudez DS, Guillette LJ, Parrott BB. Assessing impacts of precocious steroid exposure on thyroid physiology and gene expression patterns in the American alligator (Alligator mississippiensis). Gen Comp Endocrinol 2019; 271:61-72. [PMID: 30408484 DOI: 10.1016/j.ygcen.2018.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/17/2018] [Accepted: 11/04/2018] [Indexed: 10/27/2022]
Abstract
The thyroid gland is sensitive to steroid hormone signaling, and many thyroid disrupting contaminants also disrupt steroid hormone homeostasis, presenting the possibility that thyroid disruption may occur through altered steroid hormone signaling. To examine this possibility, we studied short-term and persistent impacts of embryonic sex steroid exposure on thyroid physiology in the American alligator. Alligators from a lake contaminated with endocrine disrupting contaminants (Lake Apopka, FL, USA) have been shown to display characteristics of thyroid and steroid hormone disruption. Previous studies suggest these alterations arise during development and raise the possibility that exposure to maternally deposited contaminants might underlie persistent organizational changes in both thyroidal and reproductive function. Thus, this population provides a system to investigate contaminant-mediated organizational thyroid disruption in an environmentally-relevant context. We assess the developmental expression of genetic pathways involved in thyroid hormone biosynthesis and find that expression of these genes increases prior to hatching. Further, we show that nuclear steroid hormone receptors are also expressed during this period, indicating the developing thyroid is potentially responsive to steroid hormone signaling. We then explore functional roles of steroid signaling during development on subsequent thyroid function in juvenile alligators. We exposed alligator eggs collected from both Lake Apopka and a reference site to 17β-estradiol and a non-aromatizable androgen during embryonic development, and investigated effects of exposure on hatchling morphometrics and thyroidal gene expression profiles at 5 months of age. Steroid hormone treatment did not impact the timing of hatching or hatchling size. Furthermore, treatment with steroid hormones did not result in detectable impacts on thyroid transcriptional programs, suggesting that precocious or excess estrogen and androgen exposure does not influence immediate or long-term thyroidal physiology.
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Affiliation(s)
- Thomas M Galligan
- Medical University of South Carolina, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, SC 29412, USA; Virginia Polytechnic Institute and State University, College of Natural Resources and the Environment, Department of Fish and Wildlife Conservation, 101 Cheatham Hall, 310 West Campus Drive, Blacksburg, VA 24060, USA.
| | - Matthew D Hale
- Medical University of South Carolina, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, SC 29412, USA; University of Georgia, Savannah River Ecology Laboratory, PO Drawer E, Aiken, SC 29802, USA; University of Georgia, Eugene P. Odum School of Ecology, 140 E. Green Street, Athens, GA 30602.
| | - Jessica A McCoy
- Medical University of South Carolina, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, SC 29412, USA; College of Charleston, 66 George Street, Charleston, SC 29424, USA
| | - Dieldrich S Bermudez
- Mars Inc., Global Innovation Center, 1132 W. Blackhawk Street, Chicago, IL 60642, USA
| | - Louis J Guillette
- Medical University of South Carolina, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, SC 29412, USA
| | - Benjamin B Parrott
- Medical University of South Carolina, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, SC 29412, USA; University of Georgia, Savannah River Ecology Laboratory, PO Drawer E, Aiken, SC 29802, USA; University of Georgia, Eugene P. Odum School of Ecology, 140 E. Green Street, Athens, GA 30602.
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7
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Hale MD, McCoy JA, Doheny BM, Galligan TM, Guillette LJ, Parrott BB. Embryonic estrogen exposure recapitulates persistent ovarian transcriptional programs in a model of environmental endocrine disruption†. Biol Reprod 2018; 100:149-161. [DOI: 10.1093/biolre/ioy165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 07/12/2018] [Indexed: 11/15/2022] Open
Affiliation(s)
- Matthew D Hale
- Savannah River Ecology Laboratory, Aiken, South Carolina, USA
- Odum School of Ecology, University of Georgia, Athens, Georgia, USA
| | | | - Brenna M Doheny
- School of Public Health, University of Minnesota, Minneapolis, Minnesota, USA
| | - Thomas M Galligan
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, Virginia, USA
| | - Louis J Guillette
- Marine Biomedicine and Environmental Sciences Program, Hollings Marine Laboratory, Medical University of South Carolina, Charleston, South Carolina, USA
- Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Benjamin B Parrott
- Savannah River Ecology Laboratory, Aiken, South Carolina, USA
- Odum School of Ecology, University of Georgia, Athens, Georgia, USA
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8
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Gunderson MP, Pickett MA, Martin JT, Hulse EJ, Smith SS, Smith LA, Campbell RM, Lowers RH, Boggs ASP, Guillette LJ. Variations in hepatic biomarkers in American alligators (Alligator mississippiensis) from three sites in Florida, USA. CHEMOSPHERE 2016; 155:180-187. [PMID: 27111470 PMCID: PMC4909370 DOI: 10.1016/j.chemosphere.2016.04.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 04/05/2016] [Accepted: 04/06/2016] [Indexed: 05/21/2023]
Abstract
Sub-individual biomarkers are sub-lethal biological responses commonly used in the assessment of wildlife exposure to environmental contaminants. In this study, we examined the activity of glutathione-s-transferase (GST) and lactate dehydrogenase (LDH), and metallothionein (MT) concentrations among captive-raised alligator hatchlings, wild-caught juveniles, and wild-caught adults. Juveniles and adults were collected from three locations in Florida (USA) with varying degrees of contamination (i.e. Lake Apopka (organochlorine polluted site), Merritt Island National Wildlife Refuge (NWR) (metal polluted site), and Lake Woodruff NWR (reference site)). We examined whether changes in the response of these three biomarkers were age and sex dependent or reflected site-specific variations of environmental contaminants. Juvenile alligators from Merritt Island NWR had higher MT concentrations and lower GST activity compared to those from the other two sites. This outcome was consistent with higher metal pollution at this location. Sexually dimorphic patterns of MT and GST (F > M) were observed in juvenile alligators from all sites, although this pattern was not observed in adults. GST activity was lower in captive-raised alligators from Lake Apopka and Merritt Island NWR as compared to animals from Lake Woodruff NWR, suggesting a possible developmental modulator at these sites. No clear patterns were observed in LDH activity. We concluded that GST and MT demonstrate age and sex specific patterns in the alligators inhabiting these study sites and that the observed variation among sites could be due to differences in contaminant exposure.
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Affiliation(s)
- Mark P Gunderson
- The College of Idaho, Department of Biology, 2112 Cleveland Blvd., Caldwell, ID 83605, USA.
| | - Melissa A Pickett
- The College of Idaho, Department of Biology, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
| | - Justin T Martin
- The College of Idaho, Department of Biology, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
| | - Elizabeth J Hulse
- The College of Idaho, Department of Biology, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
| | - Spenser S Smith
- The College of Idaho, Department of Biology, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
| | - Levi A Smith
- The College of Idaho, Department of Biology, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
| | - Rachel M Campbell
- The College of Idaho, Department of Biology, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
| | - Russell H Lowers
- Inomedic Health Applications, Aquatics Division, Mail Code IHA-300, Kennedy Space Center, FL, USA
| | - Ashley S P Boggs
- Marine Biomedicine and Environmental Sciences Center, Department of Obstetrics and Gynecology, Medical University South Carolina, Hollings Marine Laboratory, Charleston, SC 29412, USA
| | - Louis J Guillette
- Marine Biomedicine and Environmental Sciences Center, Department of Obstetrics and Gynecology, Medical University South Carolina, Hollings Marine Laboratory, Charleston, SC 29412, USA
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9
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Boggs ASP, Hamlin HJ, Nifong JC, Kassim BL, Lowers RH, Galligan TM, Long SE, Guillette LJ. Urinary iodine and stable isotope analysis to examine habitat influences on thyroid hormones among coastal dwelling American alligators. Gen Comp Endocrinol 2016; 226:5-13. [PMID: 26684734 PMCID: PMC4778256 DOI: 10.1016/j.ygcen.2015.12.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/20/2015] [Accepted: 12/08/2015] [Indexed: 11/29/2022]
Abstract
The American alligator, generally a freshwater species, is known to forage in marine environments despite the lack of a salt secreting gland found in other crocodylids. Estuarine and marine foraging could lead to increased dietary uptake of iodine, a nutrient necessary for the production of thyroid hormones. To explore the influence of dietary iodine on thyroid hormone health of coastal dwelling alligators, we described the seasonal plasma thyroxine and triiodothyronine concentrations measured by radioimmunoassay and urinary iodine (UI) concentrations measured by inductively coupled plasma mass spectrometry. We also analyzed long-term dietary patterns through stable isotope analysis of scute tissue. Snout-to-vent length (SVL) was a significant factor among UI and stable isotope analyses. Large adult males greater than 135cm SVL had the highest UI concentrations but did not display seasonality of thyroid hormones. Alligators under 135 SVL exhibited seasonality in thyroid hormones and a positive relationship between UI and triiodothyronine concentrations. Isotopic signatures provided supporting evidence that large males predominantly feed on marine/estuarine prey whereas females showed reliance on freshwater/terrestrial prey supplemented by marine/estuarine prey. UI measurement provided immediate information that correlated to thyroid hormone concentrations whereas stable isotope analysis described long-term dietary patterns. Both techniques demonstrate that adult alligators in coastal environments are utilizing estuarine/marine habitats, which could alter thyroid hormone physiology.
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Affiliation(s)
- Ashley S P Boggs
- National Institute of Standards and Technology, Environmental Chemical Sciences, 331 Fort Johnson Rd, Charleston, SC 29412, USA; Hollings Marine Laboratory, 331 Fort Johnson Rd, Charleston, SC 29412, USA.
| | - Heather J Hamlin
- University of Maine, School of Marine Sciences, 316 Murray Hall Orono, ME 04469, USA
| | - James C Nifong
- University of Florida, Fisheries and Aquatic Sciences, NW 71st Street, Gainsville, FL 32653, USA
| | - Brittany L Kassim
- National Institute of Standards and Technology, Environmental Chemical Sciences, 331 Fort Johnson Rd, Charleston, SC 29412, USA; Hollings Marine Laboratory, 331 Fort Johnson Rd, Charleston, SC 29412, USA
| | - Russell H Lowers
- National Aeronautics and Space Administration, InoMedic Health Applications Inc., SR 405, Kennedy Space Center, FL 32899, USA
| | - Thomas M Galligan
- Hollings Marine Laboratory, 331 Fort Johnson Rd, Charleston, SC 29412, USA; Medical University of South Carolina, Department of Obstetrics and Gynecology, 331 Fort Johnson Rd, Charleston, SC 29412, USA
| | - Stephen E Long
- National Institute of Standards and Technology, Environmental Chemical Sciences, 331 Fort Johnson Rd, Charleston, SC 29412, USA; Hollings Marine Laboratory, 331 Fort Johnson Rd, Charleston, SC 29412, USA
| | - Louis J Guillette
- Hollings Marine Laboratory, 331 Fort Johnson Rd, Charleston, SC 29412, USA; Medical University of South Carolina, Department of Obstetrics and Gynecology, 331 Fort Johnson Rd, Charleston, SC 29412, USA
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