This functional interrelation is also evidenced by reported roles of BDNF in decreasing food consumption, regulation of glucose levels, increase of cerebral energy expenditure [96,97,98], and by implications of a deficient BDNF-trkB signaling in the onset of metabolic disorders, such as obesity [99,100]. This evidence concerns the gene BDNF and obesity due to melanocortin 4 receptor deficiency.