Previous data in literature demonstrated that deletion of the BDNF gene lead to severe obesity and insatiable appetite, in addition studies with overfed and fluoxetine, showed that FX-treatment increases BDNF levels, strengthening the idea that the serotonin modulation act as an important BDNF regulator and the increase in its levels may activate the path to decrease body weight through induction of satiety (Chen et al., 2023). Here, BDNF is linked to obesity due to melanocortin 4 receptor deficiency.