title: A high-fat diet reverses improvement in glucose tolerance induced by duodenal-jejunal bypass in type 2 diabetic rats.
abstract: BACKGROUND
  Bariatric surgery offers successful resolution of type 2 diabetes mellitus (T2DM). However, recurrence of T2DM has been observed in a number of patients with initial resolution after bariatric surgery. This study aimed to induce reversal of the improvement of diabetes in T2DM rats after duodenal-jejunal bypass (DJB), and identify the effects of weight changes and gut hormones that might be involved.
  
  
  METHODS
  DJB surgery was performed in two T2DM rat models (n=20 for each group): non-obese Goto-Kakizaki (GK) rats, and moderately-obese T2DM rats induced by a combination of a high-fat diet (HFD) and low-dose streptozotocin (HS rats). The controls were sham-operated and non-treated rats. All rats were then randomly divided into HFD- and low-fat diet (LFD)-fed groups. Glucose tolerance, insulin tolerance, glucose-stimulated insulin, glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) secretion, food intake and body weight were measured and compared with controls.
  
  
  RESULTS
  DJB surgery resulted in a significant improvement in glucose tolerance in both GK and HS rats fed with either HFD or LFD. In contrast to LFD-fed rats, improved glucose tolerance was impaired in GK and HS rats fed with an HFD, accompanied by re-impairment of insulin tolerance and failure in enhancement of insulin secretion. There was no significant difference in food intake and body weight between DJB-operated and control rats, and between HFD- and LFD-fed rats. Glucose-stimulated GLP-1 and PYY levels were significantly increased after DJB surgery; however, they were not significantly different between HFD- and LFD-fed rats.
  
  
  CONCLUSIONS
  An HFD reverses the improvement in glucose tolerance induced by DJB surgery in T2DM rats, primarily ascribing to the re-impairment of insulin sensitivity, but does not change body weight, GLP-1 and PYY levels.
authors.affiliation: Department of General Surgery, Qilu Hospital of Shandong University, Experimental Center, School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Shao-zhuang
authors.initials: SZ
authors.lastname: Liu
authors.forename: Dong
authors.initials: D
authors.lastname: Sun
authors.forename: Guang-yong
authors.initials: GY
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Teng
authors.initials: T
authors.lastname: Liu
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.forename: Ming-xia
authors.initials: MX
authors.lastname: Li
authors.forename: San-yuan
authors.initials: SY
authors.lastname: Hu
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000139:chemically induced* / Q000473:pathology / Q000601:surgery*; D059305:Diet, High-Fat / Q000009:adverse effects*; D015390:Gastric Bypass; D005951:Glucose Tolerance Test; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D001786:Blood Glucose