Cold-induced hyperphagia requires AgRP-neuron activation in mice
- University of Washington, United States
- Howard Hughes Medical Institute, University of Washington, United States
- Seattle Children's Hospital, United States
Abstract
To maintain energy homeostasis during cold exposure, the increased energy demands of thermogenesis must be counterbalanced by increased energy intake. To investigate the neurobiological mechanisms underlying this cold-induced hyperphagia, we asked whether agouti-related peptide (AgRP) neurons are activated when animals are placed in a cold environment and, if so, whether this response is required for the associated hyperphagia. We report that AgRP-neuron activation occurs rapidly upon acute cold exposure, as do increases of both energy expenditure and energy intake, suggesting the mere perception of cold is sufficient to engage each of these responses. We further report that silencing of AgRP neurons selectively blocks the effect of cold exposure to increase food intake but has no effect on energy expenditure. Together, these findings establish a physiologically important role for AgRP neurons in the hyperphagic response to cold exposure.
Data availability
Photometry data has been deposited in DryadDOI: https://doi.org/10.5061/dryad.0p2ngf208Individual source data files are associated with individual figures.
Article and author information
Author details
Richard D Palmiter
Michael W Schwartz
Funding
National Institutes of Health (DK089056)
- Gregory J Morton
National Institutes of Health (T32 GM095421)
- Chelsea L Faber
National Institutes of Health (T32 HL007028)
- Jennifer Deem
Diabetes Research Center
- Jennifer Deem
American Diabetes Association (ADA 1-19-PDF-103)
- Jennifer Deem
National Institutes of Health (DK083042)
- Michael W Schwartz
National Institutes of Health (DK101997)
- Michael W Schwartz
National Institutes of Health (R37 DA033396)
- Michael Bruchas
National Institutes of Health (R01DA24908)
- Richard D Palmiter
National Institutes of Health (P30 DA048736)
- Michael Bruchas
National Institutes of Health (DK035816)
- Gregory J Morton
Diabetes Research Center (DK17047)
- Gregory J Morton
National Institutes of Health (F31 DK113673)
- Chelsea L Faber
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to a protocol approved by the institutional animal care and use committee (IACUC) of the University of Washington (#2456-06). All surgery was performed under isoflurane anesthesia, and every effort was made to minimize suffering.
Copyright
© 2020, Deem et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Cold-induced hyperphagia requires AgRP-neuron activation in mice
eLife 9:e58764.
https://doi.org/10.7554/eLife.58764
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