- The effect of gastric bypass surgery on glucose and lipid metabolism and mitochondrial respiration

This project centers on the mechanisms behind the effects of surgical gastric bypass on skeletal muscle metabolism. We focus on mitochondrial function and molecular events in skeletal muscle and adipose tissue.

The prevalence of overweight and obesity is rapidly increasing. Obesity in itself causes a major risk of cardiovascular disease and type 2 diabetes, and has a major influence on body perception and social functioning. Treatment is traditionally diet and exercise, but weight loss studies are disappointing and the results are not sustainable.

Bariatric surgery (Roux-en-Y gastric bypass (RYGB)) has a marked effect on the weight (typically weight loss of 30-75 kg, depending on the initial level) and the weight loss is sustained. Another, very favorable effect is that insulin sensitivity improves dramatically. In fact, resolution of type 2 diabetes occurs in most of the patients, and insulin sensitivity improves substantially in all. We do not know the mechanism behind this amazing effect. It is probably linked to fat and carbohydrate utilization in the skeletal muscle, and possibly via signaling molecules (or a lack thereof) from adipose tissue or from hormones produced in the gastro-intestinal tract.

Morbidly obese patients have been the subject of many psychological studies. But until now, no one has followed the patients from the period before surgery until normal weight is achieved, and compared observations of cognition, body and health perception with objectively measured phenotypically characteristics.

Research methodology 

Sixty patients (age: 30-50 years, BMI> 40 kg/m2) eligible for Roux-en-Y gastric bypass surgery will be recruited by Bariatric Center Copenhagen & Odense and by Køge hospital in Region Zeeland. 30 patients with type 2 diabetes and 30 patients without type 2 diabetes.

All patients are examined at four stages in 2 years. Twice before the surgery between which the patients loose 8 % of their body weight as per diet. Next, the patients are studied 4 and 18 months after the surgery.