Obesity has reached a crisis point in the Western world, especially in the US where one third of the population is obese, and many more are classified as overweight. A major cause of obesity is overeating, the majority of which is targeted to energy-dense, highly palatable foods. Feeding is the product of a complex interaction between humoral, metabolic, physiological and psychological processes. Regarding the latter, advances in the neurobiology of motivated behavior and addiction demonstrate that endogenous opioid peptides and dopamine are central to affective processing of rewarding stimuli, especially food, and to learning about rewards and the relevance of reward-related stimuli, making them logical suspects for focused investigation in the etiology of obesity. In the first part of this project, we will test the hypothesis that chronic consumption of energy-dense highly palatable foods disrupts opioid-dependent instrumental incentive learning processes, resulting in discordance between the pleasurable experience of palatable food consumption and the incentive value assigned to the food that guides food-seeking behavior, leading ultimately to compulsive food-seeking. The hypothesized role of disruption in endogenous opioid transmission in the basolateral amygdala will be tested using a combination of pharmacological and genetic interventions and by measurement of enkephalin release. As environmental stimuli, such as carefully engineered advertising, packaging and product placement can potently influence feeding, the second part of the project will test the hypothesis that chronic consumption of highly palatable foods accentuates cue-induced food-seeking, and that this process involves plasticity in central dopamine and/or opioid transmission. Thus, we will combine a preclinical model of diet-induced obesity with a combination of advanced behavioral, neurochemical and genetic methodologies to yield data that promise to have important implications for guiding public policy and treating overeating and obesity.

Public Health Relevance

This project will study the effect, in rodents, of long-term consumption of a highly palatable Western-style diet on behavioral mechanisms controlling the pursuit of palatable foods. The project also will examine the neurochemical underpinnings of such behavior. The results of this study will have important implications for treating overeating and obesity.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
1R01DK098709-01A1
Application #
8632699
Study Section
Neuroendocrinology, Neuroimmunology, Rhythms and Sleep Study Section (NNRS)
Program Officer
Yanovski, Susan Z
Project Start
2014-05-01
Project End
2017-04-30
Budget Start
2014-05-01
Budget End
2015-04-30
Support Year
1
Fiscal Year
2014
Total Cost
Indirect Cost
Name
University of California Los Angeles
Department
Type
Overall Medical
DUNS #
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
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Kosheleff, Alisa R; Araki, Jingwen; Tsan, Linda et al. (2018) Junk Food Exposure Disrupts Selection of Food-Seeking Actions in Rats. Front Psychiatry 9:350
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