Cornell study unravels link between bariatric surgery, diabetes remission

Researchers and human physicians have known for years that patients who receive bariatric surgeries often experience remission of Type 2 diabetes. Remission begins within days after such surgeries, well before weight loss occurs.

A recent Cornell-led study published in the journal Gut and spearheaded by a veterinary school professor provides clues to why this happens.

The study, conducted in mice, reveals that bariatric surgeries increase bile acid concentrations, and in concert with a bile acid receptor called TGR5, play critical roles in balancing glucose levels in the body, which help treat diabetes. Signaling from TGR5 was found to regulate several metabolic outcomes, including glucose homeostasis, inflammation and liver insulin signaling.

But the researchers caution that bariatric surgery may not be the answer for all patients suffering from Type 2 diabetes. “In the United States, bariatric surgeries are primarily allowed for obesity treatment, generally requiring a BMI over 40 or a BMI over 35 with significant obesity-related co-morbidities,” though some clinicians argue for expanding the use of these surgeries for treatment of diabetes, says Bethany Cummings, DVM, PhD, assistant professor of biomedical sciences in Cornell's College of Veterinary Medicine and the paper's senior author.

“Our goal is to ... identify novel therapeutic targets, because surgery is not without risks and a drug is much easier to widely distribute amongst patients,” says Cummings. The study points to TGR5 as a possible target for diabetes treatment, and more research on this receptor may also lead to treatments that exploit TGR5-bile acid links.