Research Symposium

BIO

Sawyer Cohen is a senior majoring in behavioral neuroscience. He has worked in Dr. Linda Rinaman's lab for 4 semesters and is currently working on an undergraduate research thesis. His presentation at the symposium highlights work done prior to this thesis and the projects objectives and methods. He presented his work at last year's symposium and is building on these findings in his current thesis project. He plans to graduate from Florida State this summer and continue his education in graduate school with a goal of obtaining a PhD in neuroscience. He is passionate about the connection between cognitive health and movement and diet, and wants to research how exercise can impact the brain.

Developmental Western diet alters hypothalamic satiety circuit responses to Exendin-4

Abstract

Obesity is a growing epidemic, especially in the western world. Understanding the mechanisms through which over eating causes obesity is a step towards combating the numerous health risks following obesity. Using a rodent model, I am investigating how developmental exposure to a high fat, high sugar and low protein diet (western diet) changes hunger regulation neurons in hypothalamic regions of rat offspring. It is known that western diet induces changes in central GLP1 neurons, which play a critical role in carrying out feelings of fullness and reducing food intake. These GLP1 neurons act on sub-populations of neurons in the hypothalamus to decrease hunger. Two important populations of neurons affected by GLP1 activity are POMC and NPY neurons. These populations work to regulate food intake through opposing effects, POMC neurons decrease eating while NPY neurons stimulate eating. Active GLP1 neurons increase POMC activity and decrease NPY activity. In previous work I discovered decreased GLP1 activity following a GLP1 agonist injection in developing rats exposed to western diet. To build on this, I plan to investigate how a GLP1 agonist alters activity of both POMC and NPY neurons in the hypothalamus of rat offspring. I hypothesize that changes in GLP1 neuron activity due to western diet will impact recruitment of POMC and NPY neurons following an exogenous satiety signal. I propose that POMC neuron activity, which is stimulated by GLP1, will be reduced, and NPY neurons, which are inhibited by GLP1, will be more active in western diet conditions.

Keywords: Diet GLP1 satiety obesity