title: Effects of octreotide on glucose transporter type 2 expression in obese rat small intestine.
abstract: OBJECTIVE
  To investigate the effects of the somatostatin analogue, octreotide, on maltose and sucrase activities and expression of glucose transporter type 2 (GLUT2) in obese rat intestinal mucosa.
  
  
  METHODS
  We divided 49 Sprague-Dawley rats into a group of 31 high fat diet-induced obese rats and a group of 18 normal controls. The obese rats were separated into an octreotide treated group of 16 rats and an obese group of 15. The intervention group was injected with octreotide at 40 μg/kg body weight every 12 h for 8 d. Rat body weight was measured weekly to calculate Lee's index. After euthanization, maltase and sucrase activities in the small intestine were measured by activity assays, and the fasting plasma glucose level was measured. The expression of GLUT2 in small intestinal mucosa was analyzed by immunohistochemistry, reverse transcriptase polymerase chain reaction and Western blotting assays.
  
  
  RESULTS
  Body weight, Lee's index, fasting plasma glucose level, maltase activity in small intestinal mucosa, mucosa and apical GLUT2, GLUT2 mRNA and protein expression levels were all significantly higher in the obese group than in the normal control group (605.61 ± 141.00 vs 378.54 ± 111.75, 337.61 ± 10.82 vs 318.73 ± 20.10, 8.60 ± 1.38 vs 7.33 ± 0.70, 156.01 ± 58.81 vs 50.43 ± 30.49, 390 744.2 ± 62 469.21 vs 170 546.50 ± 50 646.14, 26 740.18 ± 3809.60 vs 354.98 ± 57.19, 0.26 ± 0.11 vs 0.07 ± 0.02, and 2.08 ± 0.59 vs 1.27 ± 0.38, respectively, all P < 0.01). Sucrase activity did not differ between the two groups. Octreotide intervention significantly decreased the body weight and fasting plasma glucose level of obese rats (508.27 ± 94.39 vs 605.61 ± 141.00, 7.58 ± 1.51 vs 8.60 ±1.38, respectively, all P < 0.05). The intestinal mucosa and apical GLUT2, expression of GLUT2 mRNA and protein were also significantly lower in the octreotide intervention group than in the obese group (269 975.2 ± 53 730.94 vs 390 744.2 ± 62 469.21, 3758.06 ±364.51 vs 26 740.18 ± 3809.60, 0.08 ± 0.02 vs 0.26 ±0.11, and 1.31 ± 0.27 vs 2.08 ± 0.59, respectively, all P < 0.01).
  
  
  CONCLUSIONS
  High fat diet-induced obesity is associated with elevated intestinal maltase activity, GLUT2 expression, and permanent apical GLUT2 in the small intestinal mucosa of rats. Octreotide can inhibit these effects.
authors: Division of Peptides Related to Human Disease, National Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China.
authors: Na
authors: N
authors: Wei
authors: Rui
authors: R
authors: Liu
authors: Yan
authors: Y
authors: Ou
authors: Xian
authors: X
authors: Li
authors: Ou
authors: O
authors: Qiang
authors: Wei
authors: W
authors: Guo
authors: Cheng-Wei
authors: CW
authors: Tang
mesh_terms: D000818:Animals; D059305:Diet, High-Fat; D005765:Gastrointestinal Agents / Q000494:pharmacology*; D051273:Glucose Transporter Type 2 / Q000235:genetics / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D007421:Intestine, Small / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D009765:Obesity / Q000378:metabolism*; D015282:Octreotide / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013393:Sucrase / Q000378:metabolism; D000520:alpha-Glucosidases / Q000378:metabolism
chemical_list: D005765:Gastrointestinal Agents; D051273:Glucose Transporter Type 2; D000520:alpha-Glucosidases; D013393:Sucrase; D015282:Octreotide