Hypothalamic agouti-related peptide mRNA is elevated during natural and stress-induced anorexia

IC Dunn, PW Wilson, RB D'Eath, T Boswell

Research output: Contribution to journalArticle

8 Citations (Scopus)
1 Downloads (Pure)

Abstract

As part of their natural lives, animals can undergo periods of voluntarily reduced food intake and body weight (i.e. animal anorexias) that are beneficial for survival or breeding, such as during territorial behaviour, hibernation, migration and incubation of eggs. For incubation, a change in the defended level of body weight or ‘sliding set point’ appears to be involved, although the neural mechanisms reponsible for this are unknown. We investigated how neuropeptide gene expression in the arcuate nucleus of the domestic chicken responded to a 60–70% voluntary reduction in food intake measured both after incubation and after an environmental stressor involving transfer to unfamiliar housing. We hypothesised that gene expression would not change in these circumstances because the reduced food intake and body weight represented a defended level in birds with free access to food. Unexpectedly, we observed increased gene expression of the orexigenic peptide agouti-related peptide (AgRP) in both incubating and transferred animals compared to controls. Also pro-opiomelanocortin (POMC) mRNA was higher in incubating hens and significantly increased 6 days after exposure to the stressor. Conversely expression of neuropeptide Y and cocaine- and amphetamine-regulated transcript gene was unchanged in both experimental situations. We conclude that AgRP expression remains sensitive to the level of energy stores during natural anorexias, which is of adaptive advantage, although its normal orexigenic effects are over-ridden by inhibitory signals. In the case of stress-induced anorexia, increased POMC may contribute to this inhibitory role, whereas, for incubation, reduced feeding may also be associated with increased expression in the hypothalamus of the anorexigenic peptide vasoactive intestinal peptide.
Original languageEnglish
Pages (from-to)681 - 691
Number of pages11
JournalJournal of Neuroendocrinology
Volume27
Issue number9
DOIs
Publication statusFirst published - 2015

Fingerprint

Agouti
anorexia
peptides
pro-opiomelanocortin
body weight
food intake
amphetamine
cocaine
vasoactive intestinal peptide
neuropeptide Y
egg incubation
neuropeptides
hibernation
hypothalamus
hens
animals
chickens
gene expression
birds
breeding

Bibliographical note

52110113
1026555
62100069

Keywords

  • Broodiness
  • Energy balance
  • Maternal behaviour
  • Stress

Cite this

@article{7a4ca3373f054dc9b094631177eeb59f,
title = "Hypothalamic agouti-related peptide mRNA is elevated during natural and stress-induced anorexia",
abstract = "As part of their natural lives, animals can undergo periods of voluntarily reduced food intake and body weight (i.e. animal anorexias) that are beneficial for survival or breeding, such as during territorial behaviour, hibernation, migration and incubation of eggs. For incubation, a change in the defended level of body weight or ‘sliding set point’ appears to be involved, although the neural mechanisms reponsible for this are unknown. We investigated how neuropeptide gene expression in the arcuate nucleus of the domestic chicken responded to a 60–70{\%} voluntary reduction in food intake measured both after incubation and after an environmental stressor involving transfer to unfamiliar housing. We hypothesised that gene expression would not change in these circumstances because the reduced food intake and body weight represented a defended level in birds with free access to food. Unexpectedly, we observed increased gene expression of the orexigenic peptide agouti-related peptide (AgRP) in both incubating and transferred animals compared to controls. Also pro-opiomelanocortin (POMC) mRNA was higher in incubating hens and significantly increased 6 days after exposure to the stressor. Conversely expression of neuropeptide Y and cocaine- and amphetamine-regulated transcript gene was unchanged in both experimental situations. We conclude that AgRP expression remains sensitive to the level of energy stores during natural anorexias, which is of adaptive advantage, although its normal orexigenic effects are over-ridden by inhibitory signals. In the case of stress-induced anorexia, increased POMC may contribute to this inhibitory role, whereas, for incubation, reduced feeding may also be associated with increased expression in the hypothalamus of the anorexigenic peptide vasoactive intestinal peptide.",
keywords = "Broodiness, Energy balance, Maternal behaviour, Stress",
author = "IC Dunn and PW Wilson and RB D'Eath and T Boswell",
note = "52110113 1026555 62100069",
year = "2015",
doi = "10.1111/jne.12295",
language = "English",
volume = "27",
pages = "681 -- 691",
journal = "Journal of Neuroendocrinology",
issn = "0953-8194",
publisher = "Wiley Blackwell",
number = "9",

}

Hypothalamic agouti-related peptide mRNA is elevated during natural and stress-induced anorexia. / Dunn, IC; Wilson, PW; D'Eath, RB; Boswell, T.

In: Journal of Neuroendocrinology, Vol. 27, No. 9, 2015, p. 681 - 691.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Hypothalamic agouti-related peptide mRNA is elevated during natural and stress-induced anorexia

AU - Dunn, IC

AU - Wilson, PW

AU - D'Eath, RB

AU - Boswell, T

N1 - 52110113 1026555 62100069

PY - 2015

Y1 - 2015

N2 - As part of their natural lives, animals can undergo periods of voluntarily reduced food intake and body weight (i.e. animal anorexias) that are beneficial for survival or breeding, such as during territorial behaviour, hibernation, migration and incubation of eggs. For incubation, a change in the defended level of body weight or ‘sliding set point’ appears to be involved, although the neural mechanisms reponsible for this are unknown. We investigated how neuropeptide gene expression in the arcuate nucleus of the domestic chicken responded to a 60–70% voluntary reduction in food intake measured both after incubation and after an environmental stressor involving transfer to unfamiliar housing. We hypothesised that gene expression would not change in these circumstances because the reduced food intake and body weight represented a defended level in birds with free access to food. Unexpectedly, we observed increased gene expression of the orexigenic peptide agouti-related peptide (AgRP) in both incubating and transferred animals compared to controls. Also pro-opiomelanocortin (POMC) mRNA was higher in incubating hens and significantly increased 6 days after exposure to the stressor. Conversely expression of neuropeptide Y and cocaine- and amphetamine-regulated transcript gene was unchanged in both experimental situations. We conclude that AgRP expression remains sensitive to the level of energy stores during natural anorexias, which is of adaptive advantage, although its normal orexigenic effects are over-ridden by inhibitory signals. In the case of stress-induced anorexia, increased POMC may contribute to this inhibitory role, whereas, for incubation, reduced feeding may also be associated with increased expression in the hypothalamus of the anorexigenic peptide vasoactive intestinal peptide.

AB - As part of their natural lives, animals can undergo periods of voluntarily reduced food intake and body weight (i.e. animal anorexias) that are beneficial for survival or breeding, such as during territorial behaviour, hibernation, migration and incubation of eggs. For incubation, a change in the defended level of body weight or ‘sliding set point’ appears to be involved, although the neural mechanisms reponsible for this are unknown. We investigated how neuropeptide gene expression in the arcuate nucleus of the domestic chicken responded to a 60–70% voluntary reduction in food intake measured both after incubation and after an environmental stressor involving transfer to unfamiliar housing. We hypothesised that gene expression would not change in these circumstances because the reduced food intake and body weight represented a defended level in birds with free access to food. Unexpectedly, we observed increased gene expression of the orexigenic peptide agouti-related peptide (AgRP) in both incubating and transferred animals compared to controls. Also pro-opiomelanocortin (POMC) mRNA was higher in incubating hens and significantly increased 6 days after exposure to the stressor. Conversely expression of neuropeptide Y and cocaine- and amphetamine-regulated transcript gene was unchanged in both experimental situations. We conclude that AgRP expression remains sensitive to the level of energy stores during natural anorexias, which is of adaptive advantage, although its normal orexigenic effects are over-ridden by inhibitory signals. In the case of stress-induced anorexia, increased POMC may contribute to this inhibitory role, whereas, for incubation, reduced feeding may also be associated with increased expression in the hypothalamus of the anorexigenic peptide vasoactive intestinal peptide.

KW - Broodiness

KW - Energy balance

KW - Maternal behaviour

KW - Stress

U2 - 10.1111/jne.12295

DO - 10.1111/jne.12295

M3 - Article

VL - 27

SP - 681

EP - 691

JO - Journal of Neuroendocrinology

JF - Journal of Neuroendocrinology

SN - 0953-8194

IS - 9

ER -