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Agrp neuron activity is required for alcohol-induced overeating.

ABSTRACT: Alcohol intake associates with overeating in humans. This overeating is a clinical concern, but its causes are puzzling, because alcohol (ethanol) is a calorie-dense nutrient, and calorie intake usually suppresses brain appetite signals. The biological factors necessary for ethanol-induced overeating remain unclear, and societal causes have been proposed. Here we show that core elements of the brain's feeding circuits-the hypothalamic Agrp neurons that are normally activated by starvation and evoke intense hunger-display electrical and biochemical hyperactivity on exposure to dietary doses of ethanol in brain slices. Furthermore, by circuit-specific chemogenetic interference in vivo, we find that the Agrp cell activity is essential for ethanol-induced overeating in the absence of societal factors, in single-housed mice. These data reveal how a widely consumed nutrient can paradoxically sustain brain starvation signals, and identify a biological factor required for appetite evoked by alcohol.

SUBMITTER: Cains S

PROVIDER: S-EPMC5234092 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Agrp neuron activity is required for alcohol-induced overeating.

Cains Sarah S Blomeley Craig C Kollo Mihaly M Rácz Romeo R Burdakov Denis D

Nature communications 20170110

Alcohol intake associates with overeating in humans. This overeating is a clinical concern, but its causes are puzzling, because alcohol (ethanol) is a calorie-dense nutrient, and calorie intake usually suppresses brain appetite signals. The biological factors necessary for ethanol-induced overeating remain unclear, and societal causes have been proposed. Here we show that core elements of the brain's feeding circuits-the hypothalamic Agrp neurons that are normally activated by starvation and ev ...[more]

PMID: 28072397

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