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Blubber transcriptome responses to repeated ACTH administration in a marine mammal.

ABSTRACT: Chronic physiological stress impacts animal fitness by catabolizing metabolic stores and suppressing reproduction. This can be especially deleterious for capital breeding carnivores such as marine mammals, with potential for ecosystem-wide effects. However, the impacts and indicators of chronic stress in animals are currently poorly understood. To identify downstream mediators of repeated stress responses in marine mammals, we administered adrenocorticotropic hormone (ACTH) once daily for four days to free-ranging juvenile northern elephant seals (Mirounga angustirostris) to stimulate endogenous corticosteroid release, and compared blubber tissue transcriptome responses to the first and fourth ACTH administrations. Gene expression profiles were distinct between blubber responses to single and repeated ACTH administration, despite similarities in circulating cortisol profiles. We identified 61 and 12 genes that were differentially expressed (DEGs) in response to the first ACTH and fourth administrations, respectively, 24 DEGs between the first and fourth pre-ACTH samples, and 12 DEGs between ACTH response samples from the first and fourth days. Annotated DEGs were associated with functions in redox and lipid homeostasis, suggesting potential negative impacts of repeated stress on capital breeding, diving mammals. DEGs identified in this study are potential markers of repeated stress in marine mammals, which may not be detectable by endocrine profiles alone.

SUBMITTER: Deyarmin JS

PROVIDER: S-EPMC6390094 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Blubber transcriptome responses to repeated ACTH administration in a marine mammal.

Deyarmin Jared S JS McCormley Molly C MC Champagne Cory D CD Stephan Alicia P AP Busqueta Laura Pujade LP Crocker Daniel E DE Houser Dorian S DS Khudyakov Jane I JI

Scientific reports 20190225 1

Chronic physiological stress impacts animal fitness by catabolizing metabolic stores and suppressing reproduction. This can be especially deleterious for capital breeding carnivores such as marine mammals, with potential for ecosystem-wide effects. However, the impacts and indicators of chronic stress in animals are currently poorly understood. To identify downstream mediators of repeated stress responses in marine mammals, we administered adrenocorticotropic hormone (ACTH) once daily for four d ...[more]

PMID: 30804370

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Dataset Information

Blubber transcriptome responses to repeated ACTH administration in a marine mammal.

Publications

Blubber transcriptome responses to repeated ACTH administration in a marine mammal.

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