WEIGHT LOSS SURGERY REVERSES DIABETES: A NEW STUDY PROPOSES THE EXPLANATION
In a new study released by the University of California, Davis has found a proposed mechanism by which bariatric surgery resolves type 2 diabetes in humans. In the study, a specific line of rats known as the UC Davis type 2 diabetes mellitus rat was studied. A model was created which a surgical procedure that mimics malabsorptive human bariatric surgical procedures was employed in this special group of rats. After the procedure, a dramatic reduction in the onset of type 2 diabetes was noted 120 days later. 78% of the control group rats developed the diabetes as expected while only 38% of the rats that had undergone the surgical procedure developed diabetes.
The researchers described a hypothesis in which two specific hormones are implicated in the resolution of diabetes or the prevention of type 2 diabetes. These two hormones are known as GLP1 (Glucagon- like peptide-1) and PYY (peptide YY). These two hormones have been previously identified and are involved in regulation of insulin secretion and appetite. GLP1 is believed to increase insulin secretion and increase insulin sensitivity in the tissues, which would lead to improvement or resolution- or in this case prevention- of type 2 diabetes.
The study is important in part because some of the findings about blood sugar regulation after weight loss surgery appears to contradict the hypothesis that the phenomenon is purely weight related. While long term studies of gastric banding and gastric bypass demonstrate similar rates of diabetes resolution, short term studies indicate the gastric bypass, a malabsorptive procedure with greater hormonal changes, produces faster and earlier improvements in type 2 diabetes. The explanation for this phenomenon may lie with hormonal changes such as those that occur with GLP-1.
Undoubtedly future studies on these hormones in both animals and humans will shed greater light on the subject and help us understand how and why weight loss surgery exerts is powerful effects. In addition, such studies may lead us to new drugs, pharmaceutical solutions to the problem that will involve drugs that mimic the actions of GLP-1 or block other hormones that create harmful effects and perhaps allow a way to chemically produce the effects of weight loss surgery.
Some researchers in the field of obesity postulate that within ten years we will have a whole array of new drugs that produce some of these effects, but obesity is likely to remain a complex, multi-factorial disease with many psychological, behavioral, genetic and cultural factors that play a role.