Superior Appetite Hormone Profile After Equivalent Weight Loss by Gastric Bypass Compared to Gastric Banding

Abstract

The goal of this study was to understand the mechanisms of greater weight loss by gastric bypass (GBP) compared to gastric banding (GB) surgery. Obese weight‐ and age‐matched subjects were studied before (T0), after a 12 kg weight loss (T1) by GBP (n = 11) or GB (n = 9), and at 1 year after surgery (T2). peptide YY3–36 (PYY3–36), ghrelin, glucagon‐like peptide‐1 (GLP‐1), leptin, and amylin were measured after an oral glucose challenge. At T1, glucose‐stimulated GLP‐1 and PYY levels increased significantly after GBP but not GB. Ghrelin levels did not change significantly after either surgery. In spite of equivalent weight loss, leptin and amylin decreased after GBP, but not after GB. At T2, weight loss was greater after GBP than GB (P = 0.003). GLP‐1, PYY, and amylin levels did not significantly change from T1 to T2; leptin levels continued to decrease after GBP, but not after GB at T2. Surprisingly, ghrelin area under the curve (AUC) increased 1 year after GBP (P = 0.03). These data show that, at equivalent weight loss, favorable GLP‐1 and PYY changes occur after GBP, but not GB, and could explain the difference in weight loss at 1 year. Mechanisms other than weight loss may explain changes of leptin and amylin after GBP.

Food preferences and underlying mechanisms after bariatric surgery

“…However, ghrelin levels have been found to be reduced or increased post RYGB and therefore its impact on food preferences is largely unknown (58,59) .…”

Roux-en-Y gastric bypass: effects on feeding behavior and underlying mechanisms

“…The gut hormone system has been extensively investigated in relation to the physiological changes induced by RYGBP (56). In particular, there is now a well-established body of research documenting markedly increased meal-stimulated peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) levels after RYGBP (57)(58)(59)(60)(61)(62)(63)(64)(65)(66). The enhanced gut hormone responses occur as early as one or two days after RYGBP independent of weight loss per se (67), thus implicating a process directly related to the procedure itself.…”

Control of Food Intake by Gastrointestinal Peptides: Mechanisms of Action and Possible Modulation in the Treatment of Obesity

“…The postprandial release of CCK, GLP-1, and PYY was increased following both RYGB 189 and SG, 183,190 a finding not observed after GB for GLP-1 and pancreatic polypeptide, 181 while the regulation of CCK after GB is unknown so far. This increased postprandial release of CCK, GLP-1, and PYY might be due to faster delivery of nutrients to the distal intestinal tract following surgery and contribute to the improvement of glucose control as well as the reduction of food intake and subsequently body weight.…”