Gastric bypass surgery has proven efficacy for weight loss and improved glucose tolerance is seen even before the weight loss occurs. Researchers at Helmholtz Zentrum München and the University of Cincinnati are now reporting studies of rodent models with differing improvements in glucose tolerance with variations in response to the hormone glucagon-like peptide 1 (GLP-1). Levels of GLP-1 which increases insulin secretion to improve blood glucose and lipid levels in the gut rise significantly following the weight-loss surgery. The researchers found variability in GLP-1 responsiveness correlated with how improved the patient’s glucose tolerance was. This in turn correlated to the success of the gastric bypass surgery.
In the future, a GLP-1 response test could be performed prior to surgery to determine how effective the surgery would be for obesity with comorbid diabetes. This would need to be affirmed in human clinical trials so that surgeons can determine if performing a procedure that is not easily reversed would be beneficial for the patient. This also can determine whether the GLP-1 receptor agonist drugs are appropriate therapy for patients due to their responsiveness to a possible GLP-1 hormone response test.
- GLP-1 levels increase greatly after gastric bypass surgery and can lead to improved glucose tolerance in these patients.
- The degree of improvement is dependent on the individual patient’s responsiveness to GLP-1 formed in the gut.
- In the future a GLP-1 responsiveness test may be used pre-surgery to determine likely outcomes and individualized therapies.
Diabetes, November 2013