People who have difficulty controlling their food intake tend to overeat certain kinds of foods, such as doughnuts or chocolate, which can lead to obesity and other health-related issues. Their choices, despite popular generalization, might not actually be based on the way certain foods taste or how many calories they contain, according to a Virginia Tech researcher.
“Instead, we think problematic eating is related to the combination of ingredients in food and how they affect dopamine release, similar to the way that a drug’s abuse potential is directly related to its effect on dopamine release,” said Matt Howe, an assistant professor in the School of Neuroscience, part of the Virginia Tech College of Science.
“The meso-striatal dopamine system is a brain circuit that controls movement, learning, and motivation,” Howe said. “Understanding more about how this system is designed to work will tell us how we want potential new therapies for food and drug disorders — and even diseases like Parkinson’s, which also result from damage to this circuit — to function.”
To figure out how individual food ingredients affect the dopamine system and what happens when all of the ingredients are presented in combination, Howe recently was awarded a five-year, $1.8 million Stephen Katz Early Stage Investigator R01 by the National Institutes of Health's (NIH) National Institute of Diabetes, Digestive, and Kidney Diseases. The award is exclusively for junior faculty looking to start a program of research novel to the investigator and cannot represent an incremental advance over previously published work, according to the NIH.
Howe has used cutting-edge technologies to measure neurotransmitter release and control brain activity in precise populations of neurons in different parts of the brain, experiments that allow for directly testing hypotheses about how a specific population of cells in the brain control behavior.
With this new research, Howe will apply his own expertise and collaborate with two faculty members at the Fralin Biomedical Research Institute at VTC, who bring their own proficiencies to the project: Alexandra DiFeliceantonio, an assistant professor and associate director of the Center for Health Behaviors Research, and Read Montague, the Virginia Tech Carilion Vernon Mountcastle Research Professor, director of the Center for Human Neuroscience Research, and an affiliated member of the Department of Physics, the latter also part of the College of Science.
DiFeliceantonio, a human neuroscientist with extensive training in nutrition and basic science in model organisms such as mice, is helping to design experiments to create or block dopamine release in mice that better capture what is going on in humans.
A computational neuroscientist, Montague was part of a research team that first described how dopamine may contribute to learning and motivation. He will work on integrating the team’s data into this larger body of work.
“Using mice in our experiments allows us to directly record and manipulate brain activity, which greatly informs computational models of the function of these brain circuits,” Howe said.
The team will be assisted by former Virginia Tech faculty member Srijan Sengupta, now assistant professor of statistics at North Carolina State University, who is helping design a statistical analysis plan for this project. Two Ph.D. students in the Virginia Tech School of Neuroscience, Alec Hartle and Asia Dofat, are involved in conducting the experiments.
“Our long-term goal is to provide a foundation for future studies of how dopamine effects food intake and contribute to educating people on how they can erase patterns of behavior associated with poor food choices and eat more healthily,” Howe said.