In morbid obesity, proximal intestine glucose absorption is accelerated and related to increased SGLT-1 expression, leading to an incretin-glucagon profile promoting hyperinsulinemia and hyperglycemia. These findings are consistent with the concept that accelerated glucose absorption in the proximal gut underlies the foregut theory of obesity and type 2 diabetes.

Objective: To evaluate the effect of modulating pouch emptying (PE) and SI transit of glucose after Roux-en-Y gastric bypass (RYGB) on blood glucose, incretin hormones, glucose absorption and gastrointestinal (GI) symptoms. Methods: Ten RYGB patients were studied twice in random order, receiving either a 150 ml glucose drink (200 kcal) or the same solution infused into the proximal Roux-limb at 4 kcal/min. Data were compared with 10 healthy volunteers who received a 4 kcal/min duodenal infusion. PE, cecal arrival time (CAT), blood glucose, plasma 3-O-methylglucose (3-OMG), insulin, glucose-dependent insulinotropic polypeptide (GIP), and glucagon-like peptide-1 (GLP-1), and GI symptoms were measured. Results: In RYGB subjects, the glucose drink emptied very rapidly (PE t50 5 3 6 1 min) and intestinal glucose infusion was associated with higher blood glucose and plasma 3-OMG, but lower plasma GLP-1, GIP, insulin, and GI symptoms than oral glucose (all P < 0.001), and comparable to volunteers. In RYGB subjects, CAT correlated inversely with peak GLP-1 (r 5 20.73, P 5 0.01), and plasma 3-OMG correlated tightly blood glucose (r 5 0.94, P < 0.0001). Conclusions: After RYGB, reducing intestinal glucose delivery to 4 kcal/min is associated with higher blood glucose, greater glucose absorption, lower incretin responses, and less GI symptoms, supporting rapid transit contribution to the exaggerated incretin responses and "dumping symptoms".

Objective: To determine the effect of Roux-en-Y gastric bypass (RYGB) on the expression of intestinal sweet taste receptors (STRs), glucose transporters (GTs), glucose absorption, and glycemia. Methods: Intestinal biopsies were collected for mRNA expression of STR (T1R2) and GTs (SGLT-1 and GLUT2) from 11 non-diabetic RYGB, 13 non-diabetic obese, and 11 healthy subjects, at baseline and following a 30 min small intestinal (SI) glucose infusion (30 g/150 ml water with 3 g 3-O-methyl-D-glucopyranose (3-OMG)). Blood glucose, plasma 3-OMG, and insulin were measured for 270 min. Results: In RYGB patients, expression of both GTs was 2-fold higher at baseline and after glucose infusion than those of morbidly obese or healthy subjects (P < 0.001). STR expressions were comparable amongst the groups. Peak plasma 3-OMG in both RYGB (r 5 0.69, P 5 0.01) and obese (r 5 0.72, P 5 0.005) correlated with baseline expression of SGLT-1, as was the case with peak blood glucose in RYGB subjects (r 5 0.69, P 5 0.02). Conclusions: The upregulated intestinal GTs in RYGB patients are associated with increased glucose absorption when glucose is delivered at a physiological rate, suggesting a molecular adaptation to prevent carbohydrate malabsorption from rapid intestinal transit after RYGB.

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182 Background: Current methods of pre-operative predicting outcome of pancreatic cancer and related pancreatectomy are limited. While several prognostic biomarkers, including S100A2 and S100A4, are associated with poor outcomes, these currently can only be assessed in operatively resected specimens. The amount of tissue from EUS guided fine needle aspirations is often insufficient for biomarker assessment. Procore needles aim to acquire larger volumes of tissue that may be suitable. We aim to (i) evaluate the feasibility of S100A2 and S100A4 assessment in EUS guided biopsy specimens using the Procore needle, and (ii) evaluate the relationship of these biomarkers with outcome. Methods: Clinico-pathological data from 79 patients (70 ± 2yrs; 44M:35F) with pancreatic ductal adenocarcinoma (PDAC) were prospectively acquired. All subjects had EUS guided biopsy with a 22G Procore needle and cell-block preparation was performed. Sections of cell-block material were assessed for S100A2 and S100A4 protein expression using immunohistochemistry. Results: Pre-operative biomarker assessments from EUS acquired specimens were possible in 90% (72/79) of patients, 14 of which then had pancreatectomy. Thirty-five (49%) of patients expressed S100A2 and S100A4, which were co-expressed in 97% of cases. Patients with S100A2/A4 tumours on EUS had a significantly shorter median survival (10.0 vs. 17.5 months, p=0.03). Among patients with S100A2/A4 expressing tumors, pancreatectomy (n=8) didn't lead to a survival benefit compared with those managed non-surgically (n=27) (12.5 vs. 10.0 months, p=0.70). Of patients who had pancreatectomy, those with S100A2/A4 expressing tumors (n=8) had shorter survival than those with S100A2/A4-negative tumors (n=6) (12.5 vs. 20.5 months; p = 0.04). Conclusions: Biomarker assessment from EUS guided biopsy specimens is feasible and successful in 90% of cases. The presence of S100A2 and S100A4 expression predicts both survival and response to pancreatectomy in patients with pancreatic cancer. These findings demonstrate a “proof-of-concept”, that pre-operative EUS guided biopsy could inform clinical decision-making, particularly with regard to selection for operative resection of PDAC.