Perioperative changes in prouroguanylin hormone response in severely obese subjects after bariatric surgery

Abstract Background Prouroguanylin is a gut hormone converted into uroguanylin in the hypothalamus. Uroguanylin induces satiety through guanylyl-cyclase-2C receptor signaling. However, little is known about the role of this hormone in regulating human food intake. Methods In prospective-cohort study, prouroguanylin profile changes were determined during meal stimulation in obese patients 2 weeks before and 2 weeks after Roux-en-Y gastric bypass surgery. We also investigated whether these changes play a role in the anorexigenic effect of Roux-en-Y gastric bypass. Results The study enrolled 8 healthy lean volunteers and 10 obese patients with type 2 diabetes. Prouroguanylin levels were postprandially decreased at 30 minutes (P = .04) and 60 minutes (P = .008) in obese patients before surgery, and they were increased at 60 minutes (P = .003), 90 minutes (P = .008), and 120 minutes (P = .009) after surgery. We observed a significant difference (P = .001) in fasting prouroguanylin levels before (8.82 ± 1.2 ng/mL) and after (6.05 ± 1.2 ng/mL) Roux-en-Y gastric bypass. Hunger ratings in the fasted state did not change after Roux-en-Y gastric bypass. Instead, subjects demonstrated significantly (P = .01) lower hunger visual analog scale scores than before Roux-en-Y gastric bypass. No correlations between circulating prouroguanylin levels and hunger perception were found before or after Roux-en-Y gastric bypass. Conclusion Prouroguanylin levels decrease after meal stimulation in obese patients, and they increase after Roux-en-Y gastric bypass, but no correlations exist with hunger visual analog scale scores.