Could the improvement of obesity-related co-morbidities depend on modified gut hormones secretion?

Figure 1 Humoral signals implicated in the physiological regulation of food intake. Diagram summarising the major signalling pathways which converge on the hypothalamus and brainstem in order to regulate food intake. ARC: Arcuate nucleus; NPY/AgRP: Neuropeptide Y and agouti-related peptide; POMC/CART: Proopiomelanocortin and cocaine- and amphetamine-regulated transcript; DVC: Dorsal vagal complex; DVN: Dorsal motor nucleus of vagus; NTS: Nucleus of the tractus solitarius; AP: Area postrema; GLP-1: Glucagon-like peptide-1; CCK: Cholecystokinin; PP: Pancreatic polypeptide; PYY: Peptide YY; OXM: Oxyntomodulin.

Figure 2 Peripheral feedback signals.

Figure 3 Gastric banding: an adjustable gastric band is used to divide the stomach into a small proximal compartment taken down a few centimeters distal to the compartment (pouch) and a larger distal compartment (residual stomach). Roux-en-Y gastric bypass: The stomach is gastric inlet. The jejunum is divided 50 cm beyond the ligament of Treitz, and its aboral end is connected to the small gastric pouch. Some 150 cm distal to this point, the other end of the small bowel is sewn to a loop that has been pulled up to meet it (so-called Roux-en-Y reconstruction). Surgical effects: restriction, with an additional malabsorptive component. Sleeve gastrectomy: More than 80% of the stomach is resected, and the gastric remnant is tubularized, with an initial filling volume of less than 100 mL. Surgical effects: Restrictive and hormonal mechanisms. Biliopancreatic diversion duodenal switch (DS): The stomach is reduced in size as in sleeve gastrectomy. Duodenum is divided distal to the pylorus, and the jejunum is divided 250 cm proximal to the ileocecal valve and anastomosed to the duodenum. The other end is connected to the ileum 100 cm proximal to the ileocecal valve. Mechanism of effect: A combination of restrictive gastric surgery with a considerable degree of malabsorption.