title: Effects of intraduodenal fatty acids on appetite, antropyloroduodenal motility, and plasma CCK and GLP-1 in humans vary with their chain length.
abstract: The gastrointestinal effects of intraluminal fats may be critically dependent on the chain length of fatty acids released during lipolysis. We postulated that intraduodenal administration of lauric acid (12 carbon atoms; C12) would suppress appetite, modulate antropyloroduodenal pressure waves (PWs), and stimulate the release of cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1) more than an identical dose of decanoic acid (10 carbon atoms; C10). Eight healthy males (19-47 yr old) were studied on three occasions in a double-blind, randomized fashion. Appetite perceptions, antropyloroduodenal PWs, and plasma CCK and GLP-1 concentrations were measured during a 90-min intraduodenal infusion of 1) C12, 2) C10, or 3) control (rate: 2 ml/min, 0.375 kcal/min for C12/C10). Energy intake at a buffet meal, immediately after completion of the infusion, was also quantified. C12, but not C10, suppressed appetite perceptions (P < 0.001) and energy intake (control: 4,604 +/- 464 kJ, C10: 4,109 +/- 588 kJ, and C12: 1,747 +/- 632 kJ; P < 0.001, C12 vs. control/C10). C12, but not C10, also induced nausea (P < 0.001). C12 stimulated basal pyloric pressures and isolated pyloric PWs and suppressed antral and duodenal PWs compared with control (P < 0.05 for all). C10 transiently stimulated isolated pyloric PWs (P = 0.001) and had no effect on antral PWs but markedly stimulated duodenal PWs (P = 0.004). C12 and C10 increased plasma CCK (P < 0.001), but the effect of C12 was substantially greater (P = 0.001); C12 stimulated GLP-1 (P < 0.05), whereas C10 did not. In conclusion, there are major differences in the effects of intraduodenal C12 and C10, administered at 0.375 kcal/min, on appetite, energy intake, antropyloroduodenal PWs, and gut hormone release in humans.
authors.affiliation: NHMRC Senior Research Fellow, Department of Medicine, Royal Adelaide Hospital, North Terrace, Adelaide, South Australia 5000, Australia.
authors.forename: Kate L
authors.initials: KL
authors.lastname: Feltrin
authors.forename: Tanya J
authors.initials: TJ
authors.lastname: Little
authors.forename: James H
authors.initials: JH
authors.lastname: Meyer
authors.forename: Michael
authors.initials: M
authors.lastname: Horowitz
authors.forename: Andre J P M
authors.initials: AJ
authors.lastname: Smout
authors.forename: Judith
authors.initials: J
authors.lastname: Wishart
authors.forename: Amelia N
authors.initials: AN
authors.lastname: Pilichiewicz
authors.forename: Thomas
authors.initials: T
authors.lastname: Rades
authors.forename: Ian M
authors.initials: IM
authors.lastname: Chapman
authors.forename: Christine
authors.initials: C
authors.lastname: Feinle-Bisset
mesh_terms: D000328:Adult; D001066:Appetite / Q000187:drug effects*; D002766:Cholecystokinin / Q000097:blood*; D003652:Decanoic Acids / Q000008:administration & dosage / Q000737:chemistry; D004311:Double-Blind Method; D004386:Duodenum / Q000187:drug effects / Q000502:physiology*; D002149:Energy Intake / Q000187:drug effects; D005227:Fatty Acids / Q000008:administration & dosage*; D005769:Gastrointestinal Motility / Q000187:drug effects*; D005934:Glucagon / Q000097:blood*; D052216:Glucagon-Like Peptide 1; D006728:Hormones / Q000097:blood; D006801:Humans; D007263:Infusions, Parenteral; D007850:Lauric Acids / Q000008:administration & dosage / Q000737:chemistry; D008297:Male; D008365:Manometry; D008875:Middle Aged; D010446:Peptide Fragments / Q000097:blood*; D010865:Pilot Projects; D011312:Pressure; D011498:Protein Precursors / Q000097:blood*; D011706:Pyloric Antrum / Q000187:drug effects / Q000502:physiology*; D011708:Pylorus / Q000502:physiology; D012677:Sensation / Q000187:drug effects
chemical_list: D003652:Decanoic Acids; D005227:Fatty Acids; D006728:Hormones; D007850:Lauric Acids; D010446:Peptide Fragments; D011498:Protein Precursors; C030358:lauric acid; C031071:decanoic acid; D052216:Glucagon-Like Peptide 1; D005934:Glucagon; D002766:Cholecystokinin