Involvement of endogenous glucagon-like peptide-1(7-36) amide on glycaemia-lowering effect of oligofructose in streptozotocin-treated rats.
We have evaluated the influence of oligofructose (OFS), a fermentable dietary fibre, on glucose homeostasis, insulin production and intestinal glucagon-like peptide-1 (GLP-1) in streptozotocin-treated diabetic rats. Male Wistar rats received either i.v. streptozotocin (STZ; 40 mg/kg) or vehicle (CT); one week later, they were fed for 6 weeks with either the standard diet (STZ-CT), or with a diet containing 10% oligofructose (STZ-OFS); both diets were available ad libitum. In a second set of experiments (duration 4 weeks), a supplemental group of food-restricted rats (STZ-Res) receiving a similar intake as CT rats, was added. OFS improved glucose tolerance and reduced food intake as compared with STZ-CT rats in both the post-prandial state and after an oral glucose tolerance test. After 6 weeks, portal and pancreatic insulin concentrations were doubled in STZ-OFS rats. Food restriction improved these parameters when compared with STZ-CT rats, but to a lesser extent than in the STZ-OFS group. We have shown that OFS treatment increased portal and colonic GLP-1(7-36) amide levels and doubled colonic proglucagon and prohormone convertase 1 mRNA levels; both OFS and food restriction lowered ileal GLP-1(7-36) amide levels as compared with levels in STZ-CT rats. We propose that OFS, through its fermentation in the colon, promotes the expression and secretion of colonic peptides, namely GLP-1(7-36) amide, with beneficial consequences on glycaemia, insulin secretion and hyperphagia in diabetic rats.
Cani
Patrice D
PD
Unit of Pharmacokinetics, Metabolism, Nutrition and Toxicology, Université catholique de Louvain, Brussels, Belgium.
Daubioul
Catherine A
CA
Reusens
Brigitte
B
Remacle
Claude
C
Catillon
Grégory
G
Delzenne
Nathalie M
NM
D000199:Actins / Q000235:genetics; D000818:Animals; D001786:Blood Glucose / Q000032:analysis*; D003106:Colon / Q000737:chemistry / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000378:metabolism; D004435:Eating / Q000187:drug effects; D005285:Fermentation; D005508:Food Deprivation; D005934:Glucagon / Q000097:blood / Q000235:genetics; D052216:Glucagon-Like Peptide 1; D004763:Glucagon-Like Peptides; D005951:Glucose Tolerance Test; D007328:Insulin / Q000032:analysis / Q000097:blood; D007515:Islets of Langerhans / Q000737:chemistry; D008297:Male; D009844:Oligosaccharides / Q000627:therapeutic use*; D010446:Peptide Fragments / Q000032:analysis / Q000097:blood*; D052336:Proglucagon; D045664:Proprotein Convertase 1 / Q000235:genetics; D011498:Protein Precursors / Q000097:blood / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction
D000199:Actins; D001786:Blood Glucose; D007328:Insulin; D009844:Oligosaccharides; D010446:Peptide Fragments; D011498:Protein Precursors; D012333:RNA, Messenger; C120489:oligofructose; C055453:glucagon-like peptide 1 (7-36)amide; D052336:Proglucagon; D004763:Glucagon-Like Peptides; D052216:Glucagon-Like Peptide 1; D005934:Glucagon; D045664:Proprotein Convertase 1