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Scanes CG, Pierzchała-Koziec K, Gajewska A. Effects of Restraint Stress on Circulating Corticosterone and Met Enkephalin in Chickens: Induction of Shifts in Insulin Secretion and Carbohydrate Metabolism. Animals (Basel) 2024; 14:752. [PMID: 38473137 DOI: 10.3390/ani14050752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/20/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024] Open
Abstract
This study examined the effects of acute restraint stress in the presence or absence of naltrexone on the circulating concentrations of insulin, glucose, Met-enkephalin and corticosterone in 14-week-old chickens [design: 2 sex × 2 stress/non-stress × 2 +/- naltrexone]. In chickens (five male and five females per treatment) subjected to restraint for 30 min, there were increases in the plasma concentrations of corticosterone and Met-enkephalin. The plasma concentrations of insulin and glucose were also increased in the chickens during restraint. Moreover, there were increases in the plasma concentrations of insulin and glucose in the chickens. The patterns of expression of the proenkephalin gene (PENK) in both the anterior pituitary gland and the adrenal gland were very similar to that of plasma Met-enkephalin. There were relationships between the plasma concentrations of corticosterone, Met-enkephalin, insulin and glucose after 30 min of restraint. The effects of naltrexone treatment on both untreated and stressed chickens were also examined, with naltrexone attenuating the stress-induced increases in the plasma concentrations of corticosterone, Met-enkephalin and glucose but not in those of insulin. The present study demonstrates that stress increases insulin secretion in chickens but also induces insulin resistance.
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Affiliation(s)
- Colin G Scanes
- Department of Biological Science, University of Wisconsin Milwaukee, Milwaukee, WI 53211, USA
| | - Krystyna Pierzchała-Koziec
- Department of Animal Physiology and Endocrinology, University of Agriculture, Mickiewicza 24/28, 30-059 Kraków, Poland
| | - Alina Gajewska
- Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jablonna, Poland
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2
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Shaughnessy CA, Myhre VD, Hall DJ, McCormick SD, Dores RM. Hypothalamus-pituitary-interrenal (HPI) axis signaling in Atlantic sturgeon (Acipenser oxyrinchus) and sterlet (Acipenser ruthenus). Gen Comp Endocrinol 2023; 339:114290. [PMID: 37088167 DOI: 10.1016/j.ygcen.2023.114290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/27/2023] [Accepted: 04/19/2023] [Indexed: 04/25/2023]
Abstract
In vertebrates, the hypothalamic-pituitary-adrenal/interrenal (HPA/HPI) axis is a highly conserved endocrine axis that regulates glucocorticoid production via signaling by corticotropin releasing hormone (CRH) and adrenocorticotropic hormone (ACTH). Once activated by ACTH, Gs protein-coupled melanocortin 2 receptors (Mc2r) present in corticosteroidogenic cells stimulate expression of steroidogenic acute regulatory protein (Star), which initiates steroid biosynthesis. In the present study, we examined the tissue distribution of genes involved in HPI axis signaling and steroidogenesis in the Atlantic sturgeon (Acipenser oxyrinchus) and provided the first functional characterization of Mc2r in sturgeon. Mc2r of A. oxyrinchus and the sterlet sturgeon (Acipenser ruthenus) are co-dependent on interaction with the melanocortin receptor accessory protein 1 (Mrap1) and highly selective for human (h) ACTH over other melanocortin ligands. A. oxyrinchus expresses key genes involved in HPI axis signaling in a tissue-specific manner that is indicative of the presence of a complete HPI axis in sturgeon. Importantly, we co-localized mc2r, mrap1, and star mRNA expression to the head kidney, indicating that this is possibly a site of ACTH-mediated corticosteroidogenesis in sturgeon. Our results are discussed in the context of other studies on the HPI axis of basal bony vertebrates, which, when taken together, demonstrate a need to better resolve the evolution of HPI axis signaling in vertebrates.
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Affiliation(s)
- Ciaran A Shaughnessy
- Department of Biological Sciences, University of Denver, Denver, CO, United States.
| | - Valorie D Myhre
- Department of Biological Sciences, University of Denver, Denver, CO, United States
| | - Daniel J Hall
- U.S. Geological Survey, Eastern Ecological Science Center, S. O. Conte Anadromous Fish Research Laboratory, Turners Falls, MA, USA
| | - Stephen D McCormick
- U.S. Geological Survey, Eastern Ecological Science Center, S. O. Conte Anadromous Fish Research Laboratory, Turners Falls, MA, USA; Department of Biology, University of Massachusetts, Amherst, MA, USA
| | - Robert M Dores
- Department of Biological Sciences, University of Denver, Denver, CO, United States
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Zuloaga R, Aravena-Canales D, Aedo JE, Osorio-Fuentealba C, Molina A, Valdés JA. Effect of 11-Deoxycorticosterone in the Transcriptomic Response to Stress in Rainbow Trout Skeletal Muscle. Genes (Basel) 2023; 14:512. [PMID: 36833439 PMCID: PMC9957386 DOI: 10.3390/genes14020512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/08/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
In aquaculture, many stressors can negatively affect growth in teleosts. It is believed that cortisol performs glucocorticoid and mineralocorticoid functions because teleosts do not synthesize aldosterone. However, recent data suggest that 11-deoxycorticosterone (DOC) released during stress events may be relevant to modulate the compensatory response. To understand how DOC modifies the skeletal muscle molecular response, we carried out a transcriptomic analysis. Rainbow trout (Oncorhynchus mykiss) were intraperitoneally treated with physiological doses of DOC in individuals pretreated with mifepristone (glucocorticoid receptor antagonist) or eplerenone (mineralocorticoid receptor antagonist). RNA was extracted from the skeletal muscles, and cDNA libraries were constructed from vehicle, DOC, mifepristone, mifepristone plus DOC, eplerenone, and eplerenone plus DOC groups. The RNA-seq analysis revealed 131 differentially expressed transcripts (DETs) induced by DOC with respect to the vehicle group, mainly associated with muscle contraction, sarcomere organization, and cell adhesion. In addition, a DOC versus mifepristone plus DOC analysis revealed 122 DETs related to muscle contraction, sarcomere organization, and skeletal muscle cell differentiation. In a DOC versus eplerenone plus DOC analysis, 133 DETs were associated with autophagosome assembly, circadian regulation of gene expression, and regulation of transcription from RNA pol II promoter. These analyses indicate that DOC has a relevant function in the stress response of skeletal muscles, whose action is differentially modulated by GR and MR and is complementary to cortisol.
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Affiliation(s)
- Rodrigo Zuloaga
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago 8370146, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Concepción 4030000, Chile
| | - Daniela Aravena-Canales
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago 8370146, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Concepción 4030000, Chile
| | - Jorge Eduardo Aedo
- Departamento de Biología y Química, Facultad de Ciencias Básicas, Universidad Católica del Maule, Talca 3466706, Chile
| | - Cesar Osorio-Fuentealba
- Núcleo de Bienestar y Desarrollo Humano (NUBIDEH), Centro de Investigación en Educación (CIE-UMCE), Universidad Metropolitana de Ciencias de la Educación, Santiago 7780450, Chile
| | - Alfredo Molina
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago 8370146, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Concepción 4030000, Chile
| | - Juan Antonio Valdés
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago 8370146, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Concepción 4030000, Chile
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4
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Sobrido‐Cameán D, González‐Llera L, Anadón R, Barreiro‐Iglesias A. Organization of the corticotropin-releasing hormone and corticotropin-releasing hormone-binding protein systems in the central nervous system of the sea lamprey Petromyzon marinus. J Comp Neurol 2023; 531:58-88. [PMID: 36150899 PMCID: PMC9826344 DOI: 10.1002/cne.25412] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 08/27/2022] [Accepted: 08/30/2022] [Indexed: 01/11/2023]
Abstract
The expression of the corticotropin-releasing hormone (PmCRH) and the CRH-binding protein (PmCRHBP) mRNAs was studied by in situ hybridization in the brain of prolarvae, larvae, and adults of the sea lamprey Petromyzon marinus. We also generated an antibody against the PmCRH mature peptide to study the distribution of PmCRH-immunoreactive cells and fibers. PmCRH immunohistochemistry was combined with antityrosine hydroxylase immunohistochemistry, PmCRHBP in situ hybridization, or neurobiotin transport from the spinal cord. The most numerous PmCRH-expressing cells were observed in the magnocellular preoptic nucleus-paraventricular nucleus and in the superior and medial rhombencephalic reticular formation. PmCRH expression was more extended in adults than in larvae, and some cell populations were mainly (olfactory bulb) or only (striatum, ventral hypothalamus, prethalamus) observed in adults. The preopto-paraventricular fibers form conspicuous tracts coursing toward the neurohypophysis, but many immunoreactive fibers were also observed coursing in many other brain regions. Brain descending fibers in the spinal cord mainly come from cells located in the isthmus and in the medial rhombencephalic reticular nucleus. The distribution of PmCRHBP-expressing neurons was different from that of PmCRH cells, with cells mainly present in the septum, striatum, preoptic region, tuberal hypothalamus, pretectum, pineal complex, isthmus, reticular formation, and spinal cord. Again, expression in adults was more extended than in larvae. PmCRH- and PmCRHBP-expressing cells are different, excluding colocalization of these substances in the same neuron. Present findings reveal a complex CRH/CRHBP system in the brain of the oldest extant vertebrate group, the agnathans, which shows similarities but important divergences with that of mammals.
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Affiliation(s)
- Daniel Sobrido‐Cameán
- Department of Functional Biology, CIBUS, Faculty of BiologyUniversidade de Santiago de CompostelaSantiago de CompostelaSpain,Department of ZoologyUniversity of CambridgeCambridgeUK
| | - Laura González‐Llera
- Department of Functional Biology, CIBUS, Faculty of BiologyUniversidade de Santiago de CompostelaSantiago de CompostelaSpain
| | - Ramón Anadón
- Department of Functional Biology, CIBUS, Faculty of BiologyUniversidade de Santiago de CompostelaSantiago de CompostelaSpain
| | - Antón Barreiro‐Iglesias
- Department of Functional Biology, CIBUS, Faculty of BiologyUniversidade de Santiago de CompostelaSantiago de CompostelaSpain
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Shaughnessy CA, Jensen MF, Dores RM. A basal actinopterygian melanocortin receptor: Molecular and functional characterization of an Mc2r ortholog from the Senegal bichir (Polypterus senegalus). Gen Comp Endocrinol 2022; 328:114105. [PMID: 35973587 DOI: 10.1016/j.ygcen.2022.114105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 12/14/2022]
Abstract
In bony vertebrates, melanocortin 2 receptor (Mc2r) specifically binds adrenocorticotropic hormone (ACTH) and is responsible for mediating anterior pituitary signaling that stimulates corticosteroid production in the adrenal gland/interrenal cells. In bony fishes Mc2r requires the chaperoning of an accessory protein (Mrap1) to traffic to the membrane surface and bind ACTH. Here, we evaluated the structure and pharmacological properties of Mc2r from the Senegal bichir (Polypterus senegalus), which represents the most basal bony fish from which an Mc2r has been pharmacologically studied to date. In our experiments, cDNA constructs of the Mc2r from the Senegal bichir (sbMc2r) and various vertebrate Mrap1s were heterologously co-expressed in Chinese hamster ovary (CHO) cells, stimulated by ACTH or melanocyte-stimulating hormone (α-MSH) ligands, and assessed using a luciferase reporter gene assay. When expressed without an Mrap1, sbMc2r was not activated by ACTH. When co-expressed with Mrap1 from either chicken (Gallus gallus) or bowfin (Amia calva), sbMc2r could be activated in a dose-dependent manner by ACTH, but not α-MSH. Co-expression of sbMrap2 with sbMc2r resulted in no detectable activation of the receptor. Collectively, these results demonstrate that sbMc2r has pharmacological properties similar to those of Mc2rs of later-evolved bony fishes, such as Mrap1 dependence and ACTH selectivity, indicating that these qualities of Mc2r function are ancestral to all bony fish Mc2rs.
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Affiliation(s)
| | - Mary F Jensen
- Department of Biological Sciences, University of Denver, Denver, CO
| | - Robert M Dores
- Department of Biological Sciences, University of Denver, Denver, CO
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Mensch EL, Dissanayake AA, Nair MG, Wagner CM. The effect of putrescine on space use and activity in sea lamprey (Petromyzon marinus). Sci Rep 2022; 12:17400. [PMID: 36253421 PMCID: PMC9576135 DOI: 10.1038/s41598-022-22143-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 10/10/2022] [Indexed: 01/10/2023] Open
Abstract
Fish use odor to avoid exposure to predation and disease. Harnessing these odors as repellents is proving useful for management initiatives that conserve native species or control invasive populations. Here, we evaluated the behavioral response of invasive sea lamprey to putrescine, a decay molecule that many prey organisms avoid. Putrescine is found in tissue extracts that contain sea lamprey alarm cue, and human saliva, two mixtures known to elicit flight and avoidance responses in migratory sea lamprey. We used two behavioral assays to evaluate metrics of repellency: behavioral preference (space use) and change in activity rates and found context-dependent results. In smaller assays with individual fish, we found that putrescine had no effect on sea lamprey activity but did induce avoidance. In larger assays with multiple animals, sea lamprey did not avoid putrescine. Our results also showed consistent changes in activity and avoidance behavior in sea lamprey exposed to alarm cue in the smaller assay, concluding that this design could prove useful as a high-throughput screening tool. We also investigated a novel odor identified in sea lamprey skin, petromyzonacil, and found no behavioral effects to this odor on its own or in synergy with putrescine. Our results show limited evidence that putrescine acts as robust repellent for sea lamprey and highlight the importance of environmental context when interpreting avoidance behavior in laboratory settings.
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Affiliation(s)
- Emily L. Mensch
- grid.17088.360000 0001 2150 1785Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824 USA
| | - Amila A. Dissanayake
- grid.17088.360000 0001 2150 1785Department of Horticulture, Michigan State University, East Lansing, MI 48824 USA
| | - Muraleedharan G. Nair
- grid.17088.360000 0001 2150 1785Department of Horticulture, Michigan State University, East Lansing, MI 48824 USA
| | - C. Michael Wagner
- grid.17088.360000 0001 2150 1785Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824 USA
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Frost CR, Goss GG. Absence of some cytochrome P450 (CYP) and hydroxysteroid dehydrogenase (HSD) enzymes in hagfishes. Gen Comp Endocrinol 2022; 323-324:114045. [PMID: 35472318 DOI: 10.1016/j.ygcen.2022.114045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 04/19/2022] [Accepted: 04/21/2022] [Indexed: 11/20/2022]
Abstract
Corticosteroids are synthesized from cholesterol by steroidogenic enzyme catalysts belonging to two main families: the cytochrome p450s (CYPs) and hydroxysteroid dehydrogenases (HSDs). The action of these steroidogenic enzymes allows the genesis of the terminal active corticosteroids 11-deoxycortisol (S), 1ɑ-hydroxycorticosterone (1α-OH-B), or cortisol in different fish species. However, for Cyclostomes like hagfishes, the terminal corticosteroid is still undefined. In this study, we examined the presence or absence of CYPs and HSDs as traits in fishes to gain insight about the primary corticosteroid synthesis pathways of the hagfishes. We used published cytochrome c oxidase I (COXI) amino acid sequences to construct a phylogeny of fishes and then mapped the CYPs and HSDs as morphological traits onto the tree to predict the ancestral character states through ancestral character reconstruction (ACR). There is a clear phylogenetic signal for CYP (i.e., CYP11a1, 17, 21, and 11b) and HSD (i.e., 11-βHSD and 3β-HSD) derivatives of interest throughout the more derived fishes. Using trait-based ACR, we also found that hagfishes possess genes for 3β-HSD, CYP11a1, CYP17, and CYP21. Importantly, the presence of CYP21 implies that hagfish can synthesize 11-deoxycorticosterone (11-DOC) and S. Previous research demonstrated that despite hagfish having CYP21, neither 11-DOC nor S could be detected in hagfish. This discrepancy between the presence of steroidogenic enzymes and products brings into question the expression and/or function of CYP21 in hagfishes.
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Affiliation(s)
- Christiana R Frost
- Department of Biological Sciences, University of Alberta, CW405, Biological Sciences Building, Edmonton, AB T6G 2E9, Canada.
| | - Greg G Goss
- Department of Biological Sciences, University of Alberta, CW405, Biological Sciences Building, Edmonton, AB T6G 2E9, Canada.
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Barany A, Shaughnessy CA, Pelis RM, Fuentes J, Mancera JM, McCormick SD. Tissue and salinity specific Na +/Cl - cotransporter (NCC) orthologues involved in the adaptive osmoregulation of sea lamprey (Petromyzon marinus). Sci Rep 2021; 11:22698. [PMID: 34811419 PMCID: PMC8608846 DOI: 10.1038/s41598-021-02125-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 10/29/2021] [Indexed: 12/12/2022] Open
Abstract
Two orthologues of the gene encoding the Na+-Cl− cotransporter (NCC), termed ncca and nccb, were found in the sea lamprey genome. No gene encoding the Na+-K+-2Cl− cotransporter 2 (nkcc2) was identified. In a phylogenetic comparison among other vertebrate NCC and NKCC sequences, the sea lamprey NCCs occupied basal positions within the NCC clades. In freshwater, ncca mRNA was found only in the gill and nccb only in the intestine, whereas both were found in the kidney. Intestinal nccb mRNA levels increased during late metamorphosis coincident with salinity tolerance. Acclimation to seawater increased nccb mRNA levels in the intestine and kidney. Electrophysiological analysis of intestinal tissue ex vivo showed this tissue was anion absorptive. After seawater acclimation, the proximal intestine became less anion absorptive, whereas the distal intestine remained unchanged. Luminal application of indapamide (an NCC inhibitor) resulted in 73% and 30% inhibition of short-circuit current (Isc) in the proximal and distal intestine, respectively. Luminal application of bumetanide (an NKCC inhibitor) did not affect intestinal Isc. Indapamide also inhibited intestinal water absorption. Our results indicate that NCCb is likely the key ion cotransport protein for ion uptake by the lamprey intestine that facilitates water absorption in seawater. As such, the preparatory increases in intestinal nccb mRNA levels during metamorphosis of sea lamprey are likely critical to development of whole animal salinity tolerance.
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Affiliation(s)
- A Barany
- Department of Biology, Faculty of Marine and Environmental Sciences, Campus de Excelencia Internacional del Mar (CEI-MAR), University of Cádiz, Puerto Real, 11519, Cádiz, Spain. .,Centre of Marine Sciences (CCMar), University of Algarve, Campus de Gambelas, 8005-139, Faro, Portugal. .,Conte Anadromous Fish Research Laboratory, Eastern Ecological Science Center, U.S. Geological Survey, Turners Falls, MA, 01376, USA.
| | - C A Shaughnessy
- Conte Anadromous Fish Research Laboratory, Eastern Ecological Science Center, U.S. Geological Survey, Turners Falls, MA, 01376, USA.,Graduate Program in Organismic and Evolutionary Biology, University of Massachusetts, Amherst, MA, 01003, USA
| | - R M Pelis
- Department of Pharmaceutical Sciences, Binghamton University, State University of New York, Johnson City, NY, 13790, USA
| | - J Fuentes
- Centre of Marine Sciences (CCMar), University of Algarve, Campus de Gambelas, 8005-139, Faro, Portugal
| | - J M Mancera
- Department of Biology, Faculty of Marine and Environmental Sciences, Campus de Excelencia Internacional del Mar (CEI-MAR), University of Cádiz, Puerto Real, 11519, Cádiz, Spain
| | - S D McCormick
- Conte Anadromous Fish Research Laboratory, Eastern Ecological Science Center, U.S. Geological Survey, Turners Falls, MA, 01376, USA.,Graduate Program in Organismic and Evolutionary Biology, University of Massachusetts, Amherst, MA, 01003, USA
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Ancient fishes and the functional evolution of the corticosteroid stress response in vertebrates. Comp Biochem Physiol A Mol Integr Physiol 2021; 260:111024. [PMID: 34237466 DOI: 10.1016/j.cbpa.2021.111024] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 12/13/2022]
Abstract
The neuroendocrine mechanism underlying stress responses in vertebrates is hypothesized to be highly conserved and evolutionarily ancient. Indeed, elements of this mechanism, from the brain to steroidogenic tissue, are present in all vertebrate groups; yet, evidence of the function and even identity of some elements of the hypothalamus-pituitary-adrenal/interrenal (HPA/I) axis is equivocal among the most basal vertebrates. The purpose of this review is to discuss the functional evolution of the HPA/I axis in vertebrates with a focus on our understanding of this neuroendocrine mechanism in the most ancient vertebrates: the agnathan (i.e., hagfish and lamprey) and chondrichthyan fishes (i.e., sharks, rays, and chimeras). A review of the current literature presents evidence of a conserved HPA/I axis in jawed vertebrates (i.e., gnathostomes); yet, available data in jawless (i.e., agnathan) and chondrichthyan fishes are limited. Neuroendocrine regulation of corticosteroidogenesis in agnathans and chondrichthyans appears to function through similar pathways as in bony fishes and tetrapods; however, key elements have yet to be identified and the involvement of melanotropins and gonadotropin-releasing hormone in the stress axis in these ancient fishes warrants further investigation. Further, the identities of physiological glucocorticoids are uncertain in hagfishes, chondrichthyans, and even coelacanths. Resolving these and other knowledge gaps in the stress response of ancient fishes will be significant for advancing knowledge of the evolutionary origins of the vertebrate stress response.
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Knight K. ‘Fight or flight’ dates back to ancient ancestors. J Exp Biol 2021. [DOI: 10.1242/jeb.242837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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