Sensations unrelated to hunger, like pain, influence neural activity in the brain's hunger circuits. That's the finding of Amber Alhadeff, the winner of the 2021 Eppendorf & Science Prize for Neurobiology . Her research provides new insights into how hunger affects perception and behavior
Unraveling the mechanisms that underlie these links could aid in the development of targeted therapies for a broad range of human diseases that involve pain and weight control.
"The prize-winning research gives new insight into the complex gut-brain signaling that determines how much food we eat," said Peter Stern, senior editor at Science.
Whether we are hungry or full changes our perception of the world. It can color our mood, affect our ability to make decisions and even influence our willingness to take risks. However, while many of the mechanisms that underlie the neural control of food intake are studied and discerned, much less is known about how perception of other sensations from within the body — like pain, for example — influence neural activity in the brain's hunger circuits,and how this shapes behavior.
"Most of us feel hunger every day, often multiple times a day, but we don't often consciously think about everything that is happening in the body to generate this sensation and when we eat, to make it go away," said Alhadeff, an assistant member at the Monell Chemical Senses Center.
Using a mouse model, Alhadeff evaluated how neural circuits activated by hunger influence behavioral responses to pain and discovered a hypothalamic-to-hindbrain circuit that suppressed the sensation of pain in hungry mice, enabling them to seek food when it would otherwise be challenging to do so.
To better understand how sensory stimuli in the gut affect hunger circuits, Alhadeff used neural imaging in mice and found that different macronutrients such as fat and sugar rapidly communicate with the brain via a gut-brain pathway. According to Alhadeff, these findings highlight the role of an understudied pathway and provide insight into how different nutrients affect our brains and behavior.
"We believe that the results from our research have uncovered cellular and molecular targets that can be leveraged for the development of therapeutics for pain and weight loss," said Alhadeff. "In the future, it will be important to determine if long-term manipulation of these neural circuits has effects in disease models, such as models of obesity or chronic neuropathic pain."
The Eppendorf & Science Prize for Neurobiology recognizes the increasingly active and important role of neurobiology in advancing our understanding of the functioning of the brain and the nervous system. The winner receives $25,000 and publication of his or her essay in the October 29 issue of Science.
"Eppendorf and Science have been presenting this prize together for 20 years. This is an amazing legacy," said Eva van Pelt, co-CEO of Eppendorf SE. "I enjoy watching the careers of our awardees develop over time as they become true opinion leaders in their field."
Alhadeff will be honored at a virtual prize ceremony for the Eppendorf & Science prize for Neurobiology on November 9. The event is free and open to the public and will be livestreamed at www.eppendorf.com/prizeceremony2021.
Justin Rustenhoven is a 2021 finalist for his essay, "A Privileged Brain: Local neuroimmune collaboration safeguards the central nervous system." Rustenhoven received undergraduate degrees and a Ph.D. from the University of Auckland in New Zealand and completed postdoctoral training at Washington University in St. Louis, where he continues to work as a research fellow. His work focuses on the mechanisms underlying immune surveillance of the central nervous system from the brain's borders.
Andreas Keller is a 2021 finalist for his essay, "Hidden in Plain Sight: Context controls the activity of sensory neurons." Keller received undergraduate and graduate degrees from ETH Zürich, Switzerland, and afterwards postdoctoral training at the University of San Francisco. Most recently, Keller has established his laboratory at the Institute of Molecular and Clinical Ophthalmology Basel, Switzerland, where his research explores the mechanisms of cortical plasticity in feedforward and feedback circuits.
[Credit for associated image: Hanna Knutsson | Flickr]