EFFECTS OF ACUTE AND CHRONIC LIGHT EXPOSURE ON HEDONIC EATING BEHAVIOR: MOLECULAR AND NEUROBIOLOGICAL MECHANISMS
Anayanci Masis Vargas
Supervisors: Jorge Mendoza and Andries Kalsbeek
Light is the principal synchronizer for the mammalian circadian clock in the suprachiasmatic nucleus (SCN). Intrinsically photosensitive retinal ganglion cells (ipRGCs), expressing the photopigment melanopsin, respond directly to light and send this information to different brain regions, including the SCN, which may modulate diverse behaviors, such as locomotion, mood and feeding.
In addition to homeostatic- also hedonic mechanisms are thought to be a major determinant for food intake, particularly for palatable foods. For the homeostatic pathway, nuclei from the mediobasal hypothalamus, such as the arcuate nuclei and the lateral hypothalamus, play an important role, on the other hand corticolimbic structures are more implicated in the reward aspect of feeding. Interestingly, some of these structures receive projections from the retinal ipRGCs cells. Hence, light in some way might regulate feeding behavior and metabolism.
Therefore, the aim of this project is to study the acute and chronic effects of light (at different times of the day, different intensities and wavelengths) on regular and palatable food intake and metabolism in mice, and to reveal the possible neurobiological mechanism implicated.
Modified from: Hatori, M. and Panda, S. Trends in Molecular Medicine 2010 16, 435-446 and Hattar, S. et al. J Comp Neurol. 2006 July 20; 497(3): 326–349.