Research projects

Research projectsIn our laboratory we study food intake regulation by the brain. We seek to answer the following questions: why does eating sometimes come out of the control and how do eating disorders develop? More specifically, our research projects are focused on the neuronal mechanisms of the development of binge eating.

To address this problem, we created a rat model of binge-like eating developed by chronic stress, repeated food restriction and refeeding on palatable food. These conditions were chosen because binge-eating episodes usually occur as attempts to cope with stress. Binge eating involves highly palatable food and is frequently followed by food restriction or dieting that by itself increases the risk of relapse into bingeing. Thus far, there are no specific treatments for eating disorders in general and binge eating in particular. The reason for the limited progress in the development of treatment strategies is that the neurological mechanisms of eating disorders are not fully understood and cannot be easily studied in humans.

Research projectsTherefore, there is a great need for adequate animal models. Our binge-eating rat model consumes a large amount of sucrose in the non-hungry state, eats much more rapidly than normal, and consumes within a discrete period an amount of sucrose that is significantly higher than the control rats are able to eat within a similar period under similar circumstances. These characteristics replicate those of binge-eating disorder given by the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition).

Research projectsOur model has revealed that in the normal state, feeding is under control of the homeostatic brain centers. However, the development of binge eating displaced food intake control to the brain regions involved in reward and addiction.

One of our research projects investigates the mechanisms of this dynamical shift of the neuronal activity.

Another piece of the puzzle is that the bingeing episodes usually represent attempts to cope with chronic stress by overeating palatable food. This fact by itself is quite surprising given that evolutionarily the role of stress was to decrease appetite and inhibit digestion to help with managing a stressful situation.

The second project studies how chronic stress alters the neuronal mechanisms which instead of an anorectic reaction would trigger overeating episodes in response to stress in binge eating model.

Research projectsAnother puzzling problem which we are trying to solve: why is the rate of incidence of eating disorders approximately 10 times higher for women compared to men? To study this problem, we developed a rat model in which chronic stress and repeated food restriction trigger overeating and increase in body weight in female but not male rats. This model showed a possible implication of some specific orexigenic neuropeptides in chronic stress-induced overeating in females.

The general goal of our research program is to generate new knowledge about the neuronal mechanisms regulating feeding and involving in the development of eating disorders, and to propose new therapeutic solutions.