title: Intraduodenal administration of intact pea protein effectively reduces food intake in both lean and obese male subjects.
abstract: BACKGROUND
  Human duodenal mucosa secretes increased levels of satiety signals upon exposure to intact protein. However, after oral protein ingestion, gastric digestion leaves little intact proteins to enter the duodenum. This study investigated whether bypassing the stomach, through intraduodenal administration, affects hormone release and food-intake to a larger extent than orally administered protein in both lean and obese subjects.
  
  
  METHODS
  Ten lean (BMI:23.0±0.7 kg/m²) and ten obese (BMI:33.4±1.4 kg/m²) healthy male subjects were included. All subjects randomly received either pea protein solutions (250 mg/kg bodyweight in 0.4 ml/kg bodyweight of water) or placebo (0.4 ml/kg bodyweight of water), either orally or intraduodenally via a naso-duodenal tube. Appetite-profile, plasma GLP-1, CCK, and PYY concentrations were determined over a 2 h period. After 2 h, subjects received an ad-libitum meal and food-intake was recorded.
  
  
  RESULTS
  CCK levels were increased at 10(p<0.02) and 20(p<0.01) minutes after intraduodenal protein administration (IPA), in obese subjects, compared to lean subjects, but also compared to oral protein administration (OPA)(p<0.04). GLP-1 levels increased after IPA in obese subjects after 90(p<0.02) to 120(p<0.01) minutes, compared to OPA. Food-intake was reduced after IPA both in lean and obese subjects (-168.9±40 kcal (p<0.01) and -298.2±44 kcal (p<0.01), respectively), compared to placebo. Also, in obese subjects, food-intake was decreased after IPA (-132.6±42 kcal; p<0.01), compared to OPA.
  
  
  CONCLUSIONS
  Prevention of gastric proteolysis through bypassing the stomach effectively reduces food intake, and seems to affect obese subjects to a greater extent than lean subjects. Enteric coating of intact protein supplements may provide an effective dietary strategy in the prevention/treatment of obesity.
authors.affiliation: Department of Human Biology, Maastricht University Medical Center, Maastricht, The Netherlands. M.Geraedts@HB.unimaas.nl
authors.forename: Maartje C P
authors.initials: MC
authors.lastname: Geraedts
authors.forename: Freddy J
authors.initials: FJ
authors.lastname: Troost
authors.forename: Marjet J M
authors.initials: MJ
authors.lastname: Munsters
authors.forename: Jos H C H
authors.initials: JH
authors.lastname: Stegen
authors.forename: Rogier J
authors.initials: RJ
authors.lastname: de Ridder
authors.forename: Jose M
authors.initials: JM
authors.lastname: Conchillo
authors.forename: Joanna W
authors.initials: JW
authors.lastname: Kruimel
authors.forename: Ad A M
authors.initials: AA
authors.lastname: Masclee
authors.forename: Wim H M
authors.initials: WH
authors.lastname: Saris
mesh_terms: D002766:Cholecystokinin / Q000097:blood; D004435:Eating / Q000187:drug effects*; D054439:Ghrelin / Q000097:blood; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D006801:Humans; D008297:Male; D009765:Obesity / Q000097:blood / Q000378:metabolism*; D018532:Pisum sativum / Q000737:chemistry*; D019894:Peptide YY / Q000097:blood; D010940:Plant Proteins / Q000494:pharmacology*; D013851:Thinness / Q000097:blood / Q000378:metabolism*
chemical_list: D054439:Ghrelin; D010940:Plant Proteins; D019894:Peptide YY; D052216:Glucagon-Like Peptide 1; D002766:Cholecystokinin