Corticosterone selectively decreases humoral immunity in female eiders during incubation [PDF]
J. Exp. Biol. 209 (2006) 4957-4965, 2007 Immunity is hypothesized to share limited resources with other physiological functions and this may partly account for the fitness costs of reproduction. Previous studies have shown that the acquired immunity of female common eider ducks (Somateria mollissima) is suppressed during their incubation, during which they entirely fast.
arxiv +1 more source
Innate immunity, assessed by plasma NO measurements, is not suppressed during the incubation fast in eiders [PDF]
Dev. Comp. Immunol. (19/12/2006) 29 pages, 2007 Immunity is hypothesized to share limited resources with other physiological functions and may mediate life history trade-offs, for example between reproduction and survival. However, vertebrate immune defense is a complex system that consists of three components.
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Intestinal gluconeogenesis and glucose transport according to body fuel availability in rats [PDF]
J Physiol 566 (15/07/2005) 575-86, 2007 Intestinal hexose absorption and gluconeogenesis have been studied in relation to refeeding after two different fasting phases: a long period of protein sparing during which energy expenditure is derived from lipid oxidation (phase II), and a later phase characterized by a rise in plasma corticosterone triggering protein catabolism (phase III).
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Intestinal apoptotic changes linked to metabolic status in fasted and refed rats [PDF]
Pflugers Arch 451 (03/2006) 749-759, 2007 Intestinal apoptosis and expression of apoptosis inducers - the cytokines TNFalpha, TGFbeta1 - and the intestinal transcription factor Cdx2, were studied according to two different metabolic and hormonal phases which characterize long-term fasting: the long period of protein sparing during which energy expenditure is derived from lipid oxidation (phase
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Brief increases in corticosterone affect morphology, stress responses, and telomere length, but not post-fledging movements, in a wild songbird [PDF]
, 2018 Organisms are frequently exposed to challenges during development, such as poor weather and food shortage. Such challenges can initiate the hormonal stress response, which involves secretion of glucocorticoids. Although the hormonal stress response helps organisms deal with challenges, long-term exposure to high levels of glucocorticoids can have ...
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Reduced steroid activation of elephant shark glucocorticoid and mineralocorticoid receptors after inserting four amino acids from the DNA-binding domain of lamprey corticoid receptor-1 [PDF]
arXiv, 2023 Atlantic sea lamprey contains two corticoid receptors (CRs), CR1 and CR2, that are identical except for a four amino acid insert (Thr-Arg-Gln-Gly) in the CR1 DNA-binding domain (DBD). Steroids are stronger transcriptional activators of CR2 than of CR1 suggesting that the insert reduces the transcriptional response of lamprey CR1 to steroids. The DBD in
arxiv
Regulation by Progestins, Corticosteroids and RU486 of Activation of Elephant Shark and Human Progesterone Receptors: An Evolutionary Perspec [PDF]
arXiv, 2021 We investigated progestin and corticosteroid activation of the progesterone receptor (PR) from elephant shark (Callorhinchus milii), a cartilaginous fish belonging to the oldest group of jawed vertebrates. Comparison with human PR experiments provides insights into the evolution of steroid activation of human PR.
arxiv
Aldosterone and Dexamethasone Activate African Lungfish Mineralocorticoid Receptor: Increased Activation After Removal of the Amino-Terminal Domain [PDF]
arXiv, 2021 Aldosterone, the main physiological mineralocorticoid in humans and other terrestrial vertebrates, first appears in lungfish, which are lobe-finned fish that are forerunners of terrestrial vertebrates. Aldosterone activation of the MR regulates internal homeostasis of water, sodium and potassium, which was critical in the conquest of land by ...
arxiv
Optical study of stress hormone-induced nanoscale structural alteration in brain using partial wave spectroscopic (PWS) microscopy [PDF]
arXiv, 2017 Chronic stress affects nano to microscale structures of the brain cells/tissues due the suppression of neural growths and reconnections, hence the neuronal activities. This results in depression, memory loss and even the death of the brain cells. Our recently developed novel optical technique, partial wave spectroscopic (PWS) microscopy has nanoscale ...
arxiv
Transcriptional Activation of Elephant Shark Mineralocorticoid Receptor by Corticosteroids, Progesterone and Spironolactone [PDF]
arXiv, 2018 We report the analysis of activation by corticosteroids and progesterone of full-length mineralocorticoid receptor (MR) from elephant shark, a cartilaginous fish belonging to the oldest group of jawed vertebrates. Based on their measured activities, aldosterone, cortisol, 11-deoxycorticosterone, corticosterone, 11-deoxcortisol, progesterone and 19 ...
arxiv