Figure 2: Neural circuits that induce or oppose obesity revealed by mouse models of neuromodulation.

A) Circuits that induce feeding or inhibit thermogenesis. In the Arcuate Nucleus (ARC), neurons that send positive feeding cues are characterized by Agouti Related Peptide (AGRP) and their downstream targets in the Dorsal Raphe Nucleus (DRN) are characterized by Vesicular GABA Transporter (Vgat). B) Circuits that induce satiety or lipolysis. ARC neurons that send these signals are characterized by Proopiomelanocortin (POMC), while DRN neurons that oppose feeding are characterized by Vesicular Glutamate Transporter 3 (VGLUT3). While most of these circuits have been investigated with optogenetics or chemogenetics, Deep Brain Stimulation (DBS) of the Nucleus Accumbens (NA) shows that these neurons reduce feeding by inhibiting the Lateral Hypothalamic Area (LHA). AGRP, Agouti Related Peptide; ARC, Arcuate nucleus; BNST, Bed Nucleus of the Stria Terminalis; BAT, Brown Adipose Tissue; DRN, Dorsal Raphe Nucleus; LHA, Lateral Hypothalamic Area; MC4R, Melanocortin 4 Receptor; NA, Nucleus Accumbens; PVN, Paraventricular Nucleus; RPa, Raphe Palladius; POMC, Proopiomelanocortin; TH, Tyrosine Hydroxylase; VMH, Ventromedial Hypothalamus; Vgat, Vesicular GABA Transporter; VGLUT3, Vesicular Glutamate Transporter 3; WAT, White Adipose Tissue. Created with BioRender.com