BACKGROUND: In 2008, Troy et al. hypothesised that under fasting conditions, intestinal gluconeogenesis generates glucose levels in the portal vein which trigger the portal sensor to change insulin resistance and that this mechanism contributes to the effects of Roux-en-Y gastric bypass (RYGB) surgery on type 2 diabetes mellitus (T2DM). In a recent paper, Kashyap et al. (Int J Obes 34(3):426-471, 2010) cited this hypothesis as a potential explanation for the early changes in insulin sensitivity and beta cell function seen after RYGB. We proposed a study to examine this possibility. METHODS: We simultaneously sampled fasting portal venous blood and central venous blood in 28 patients (eight diabetics and 20 non-diabetics) before and again six days after RYGB surgery in morbidly obese patients, for measurement of glucose levels. RESULTS: We found no significant difference in the glucose levels from the two sites either before or after RYGB in diabetic patients and a small, but significant difference in the post-operative glucose levels from non-diabetic patients (4.2 vs 4.0 mM, p < 0.0001). CONCLUSIONS: Direct simultaneous measurement of fasting glucose in portal and central venous blood before and 6 days after RYGB provides no evidence to support the hypothesis that intestinal gluconeogenesis contributes to the resolution of T2DM seen after RYGB.
BACKGROUND: In 2008, Troy et al. hypothesised that under fasting conditions, intestinal gluconeogenesis generates glucose levels in the portal vein which trigger the portal sensor to change insulin resistance and that this mechanism contributes to the effects of Roux-en-Y gastric bypass (RYGB) surgery on type 2 diabetes mellitus (T2DM). In a recent paper, Kashyap et al. (Int J Obes 34(3):426-471, 2010) cited this hypothesis as a potential explanation for the early changes in insulin sensitivity and beta cell function seen after RYGB. We proposed a study to examine this possibility. METHODS: We simultaneously sampled fasting portal venous blood and central venous blood in 28 patients (eight diabetics and 20 non-diabetics) before and again six days after RYGB surgery in morbidly obesepatients, for measurement of glucose levels. RESULTS: We found no significant difference in the glucose levels from the two sites either before or after RYGB in diabeticpatients and a small, but significant difference in the post-operative glucose levels from non-diabeticpatients (4.2 vs 4.0 mM, p < 0.0001). CONCLUSIONS: Direct simultaneous measurement of fasting glucose in portal and central venous blood before and 6 days after RYGB provides no evidence to support the hypothesis that intestinal gluconeogenesis contributes to the resolution of T2DM seen after RYGB.
Authors: S R Kashyap; S Daud; K R Kelly; A Gastaldelli; H Win; S Brethauer; J P Kirwan; P R Schauer Journal: Int J Obes (Lond) Date: 2009-12-22 Impact factor: 5.095
Authors: W J Pories; M S Swanson; K G MacDonald; S B Long; P G Morris; B M Brown; H A Barakat; R A deRamon; G Israel; J M Dolezal Journal: Ann Surg Date: 1995-09 Impact factor: 12.969
Authors: Nima Saeidi; Luca Meoli; Eirini Nestoridi; Nitin K Gupta; Stephanie Kvas; John Kucharczyk; Ali A Bonab; Alan J Fischman; Martin L Yarmush; Nicholas Stylopoulos Journal: Science Date: 2013-07-26 Impact factor: 47.728