Jejunal nutrient sensing is required for duodenal-jejunal bypass surgery to rapidly lower glucose concentrations in uncontrolled diabetes

Nat Med. 2012 Jun;18(6):950-5. doi: 10.1038/nm.2745.

Abstract

Gastrointestinal bypass surgeries restore metabolic homeostasis in patients with type 2 diabetes and obesity(1), but the underlying mechanisms remain elusive. Duodenal-jejunal bypass surgery (DJB), an experimental surgical technique that excludes the duodenum and proximal jejunum from nutrient transit(1,2), lowers glucose concentrations in nonobese type 2 diabetic rats(2–5). Given that DJB redirects and enhances nutrient flow into the jejunum and that jejunal nutrient sensing affects feeding(6,7), the repositioned jejunum after DJB represents a junction at which nutrients could regulate glucose homeostasis. Here we found that intrajejunal nutrient administration lowered endogenous glucose production in normal rats through a gut-brain-liver network in the presence of basal plasma insulin concentrations. Inhibition of jejunal glucose uptake or formation of long chain fatty acyl-coA negated the metabolic effects of glucose or lipid, respectively, in normal rats, and altered the rapid (2 d) glucose-lowering effect induced by DJB in streptozotocin (STZ)-induced uncontrolled diabetic rats during refeeding. Lastly, in insulin-deficient autoimmune type 1 diabetic rats and STZ-induced diabetic rats, DJB lowered glucose concentrations in 2 d independently of changes in plasma insulin concentrations, food intake and body weight. These data unveil a glucoregulatory role of jejunal nutrient sensing and its relevance in the early improvement of glycemic control after DJB in rat models of uncontrolled diabetes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Glucose / analysis*
  • Diabetes Mellitus, Experimental / blood
  • Diabetes Mellitus, Experimental / surgery*
  • Duodenum / surgery*
  • Gastric Bypass
  • Jejunum / surgery*
  • Male
  • Rats
  • Rats, Sprague-Dawley
  • Streptozocin

Substances

  • Blood Glucose
  • Streptozocin