Leptin and insulin signaling in the hypothalamus are key to the central regulation of glucose and energy expenditure. Of particular importance is PI3K signaling in the ventromedial hypothalamus (VMH), a brain region central for the regulation of sympathetic outflow. Our preliminary results reveal the complex nature of PI3K signaling, with multiple subunits, each responsible for different aspects of energy homeostasis. Within this application we have developed novel mouse genetic tools to study the physiological requirements for the PI3K pathway and leptin signaling in anatomically identified SF1 neurons. Furthermore, we will examine how these pathways converge to mediate the beneficial effects of exercise. Together, these studies will increase our understanding of the biological control of energy balance, how it relates to exercise, and will provide mechanistic insights to the effectiveness and safety of newly approved anti-obesity drugs.

Public Health Relevance

The aim of this proposal is to gain a deeper understanding of how the brain regulates glucose, insulin, lipids, and energy expenditure to meet various metabolic challenges, including high calorie diets and physical exercise.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK100659-03
Application #
9060307
Study Section
Integrative Physiology of Obesity and Diabetes Study Section (IPOD)
Program Officer
Hyde, James F
Project Start
2014-07-08
Project End
2018-05-31
Budget Start
2016-06-01
Budget End
2017-05-31
Support Year
3
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of Texas Sw Medical Center Dallas
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
800771545
City
Dallas
State
TX
Country
United States
Zip Code
75390
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