Enterostatin decreases postprandial pancreatic UCP2 mRNA levels and increases plasma insulin and amylin.
This study investigated the chronic effect of enterostatin on body weight and some of the associated changes in postprandial metabolism. Rats were adapted to 6 h of food access/day and a choice of low-fat and high-fat (HF) food and then given enterostatin or vehicle by an intraperitoneally implanted minipump delivering 160 nmol enterostatin/h continuously over a 5-day infusion period. Enterostatin resulted in a slight but significant reduction of HF intake and body weight. After the last 6-h food access period, enterostatin-treated animals had lower plasma triglyceride and free fatty acid but higher plasma glucose and lactate levels than control animals. Enterostatin infusion resulted in increased uncoupling protein-2 (UCP2) expression in various tissues, including epididymal fat and liver. UCP2 was reduced in the pancreas of enterostatin-treated animals, and this was associated with increased plasma levels of insulin and amylin. Whether these two hormones are involved in the observed decreased food intake due to enterostatin remains to be determined. As lipid metabolism appeared to be altered by enterostatin, we measured peroxisome proliferator-activated receptor (PPAR) expression in tissues and observed that PPARalpha, -beta, -gamma1, and -gamma2 expression were modified by enterostatin in epididymal fat, pancreas, and liver. This further links altered lipid metabolism with body weight loss. Our data suggest that alterations in UCP2 and PPARgamma2 play a role in the control of insulin and amylin release from the pancreas. This implies that enterostatin changes lipid and carbohydrate metabolic pathways in addition to its effects on food intake and energy expenditure.
Arsenijevic
Denis
D
Institute of Animal Sciences, Eidegnossische Technische Hochschule Zurich, Schwerzenbach, Switzerland. denis.arsenijevic@inw.agrl.ethz.ch
Gallmann
Eva
E
Moses
William
W
Lutz
Thomas
T
Erlanson-Albertsson
Charlotte
C
Langhans
Wolfgang
W
D000682:Amyloid / Q000097:blood*; D000818:Animals; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D003089:Colipases / Q000494:pharmacology*; D004792:Enzyme Precursors; D005786:Gene Expression Regulation / Q000187:drug effects; D007328:Insulin / Q000097:blood*; D007473:Ion Channels; D058228:Islet Amyloid Polypeptide; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D010179:Pancreas / Q000378:metabolism*; D047492:Peroxisome Proliferator-Activated Receptors / Q000378:metabolism*; D019518:Postprandial Period / Q000187:drug effects / Q000502:physiology*; D011498:Protein Precursors / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution; D000071246:Uncoupling Protein 2
D000682:Amyloid; D003089:Colipases; D004792:Enzyme Precursors; D007328:Insulin; D007473:Ion Channels; D058228:Islet Amyloid Polypeptide; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D047492:Peroxisome Proliferator-Activated Receptors; D011498:Protein Precursors; D012333:RNA, Messenger; C000604391:Ucp2 protein, rat; D000071246:Uncoupling Protein 2; C037107:procolipase