GLP1R and obesity due to melanocortin 4 receptor deficiency: GLP-1 receptor agonists (GLP-1 RA) are used in the metabolic control of obesity and T2DM patients because they enhance glucose-dependent insulin synthesis and secretion, proliferation of β-cells, inhibition of β-cells apoptosis, delay of gastric emptying and regulation of appetite by satiety-effects with body weight reduction [323,324,325].