Changes of Resting Energy Expenditure in Type 2 Diabetes Rats After Roux-en-Y Gastric Bypass.

BACKGROUND: This study aimed to investigate the changes of resting energy expenditure (REE) induced by Roux-en-Y gastric bypass (RYGB) in diabetic rats. METHODS: Thirty male Goto-Kakizaki rats were randomly divided into RYGB, sham RYGB (SR), and control groups. Glucose metabolism, energy expenditure, triiodothyronine, and bile acid levels were measured. Body composition in different groups was compared after sacrifice. RESULTS: RYGB induced significant diabetic improvement, with decreased maximum food intake and body weight. There was no significant difference in the REE between the groups before surgery (P = 0.74), while the REE of the RYGB group (1.15 +/- 0.17 ml/h/g) was higher than that of the SR group (0.99 +/- 0.13 ml/h/g) and the control group (0.97 +/- 0.13 ml/h/g, P = 0.031) at the 20th postoperative week. The ratio of white adipose tissue in the RYGB group was lower (P = 0.02), and the ratio of brown adipose tissue was higher than that of the SR group and the control group (P = 0.045). Moreover, a higher bile acid level was detected in the RYGB group (6.4 +/- 1.8 mumol/L) than in the SR group (4.2 +/- 1.7 mumol/L) and the control group (4.0 +/- 2.0 mumol/L, P = 0.025). CONCLUSIONS: RYGB induces a higher REE level in diabetic rats. The circulating bile acid level was enhanced after surgery.