Blanca Lizarbe1, Maria Lusia Garcia-Martin2, 3, Pilar Lopez-Larrubia1, Sebastian Cerdan1
1Instituto Investigaciones Biomedicas "Alberto Sols", Madrid, Spain; 2Magnetic Ressonance Unit, Clinica Nuestra Senora del Rosario, Madrid, Spain; 3Head Nano-Imaging Facility, Parque Tecnolgico de Andaluca, Malaga, Spain
We report on the use of functional DWI as a robust marker of hypothalamic activation by fasting in human subjects. Six adult male where imaged (DWI, three directions) in two different situations, fed (after one week of a balanced diet), and after 24 hours of fasting. Two areas of the brain, the hypothalamus and the cortex, were investigated using a biexponential model of diffusion. Fasting is shown to elicit significant, and directionally-dependent, changes of the biexponential diffusion parameters in the hypothalamus, suggesting an activation-induced cell swelling. These results open the possibility to examine feeding disorders and their therapies by DWI.