title: Enhancement of intragastric acid stability of a fat emulsion meal delays gastric emptying and increases cholecystokinin release and gallbladder contraction.
abstract: Preprocessed fatty foods often contain calories added as a fat emulsion stabilized by emulsifiers. Emulsion stability in the acidic gastric environment can readily be manipulated by altering emulsifier chemistry. We tested the hypothesis that it would be possible to control gastric emptying, CCK release, and satiety by varying intragastric fat emulsion stability. Nine healthy volunteers received a test meal on two occasions, comprising a 500-ml 15% oil emulsion with 2.5% of one of two emulsifiers that produced emulsions that were either stable (meal A) or unstable (meal B) in the acid gastric environment. Gastric emptying and gallbladder volume changes were assessed by MRI. CCK plasma levels were measured and satiety scores were recorded. Meal B layered rapidly owing to fat emulsion breakdown. The gastric half-emptying time of the aqueous phase was faster for meal B (72 +/- 13 min) than for meal A (171 +/- 35 min, P < 0.008). Meal A released more CCK than meal B (integrated areas, respectively 1,095 +/- 244 and 531 +/- 111 pmol.min.l(-1), P < 0.02), induced a greater gallbladder contraction (P < 0.02), and decreased postprandial appetite (P < 0.05), although no significant differences were observed in fullness and hunger. We conclude that acid-stable emulsions delayed gastric emptying and increased postprandial CCK levels and gallbladder contraction, whereas acid-instability led to rapid layering of fat in the gastric lumen with accelerated gastric emptying, lower CCK levels, and reduced gallbladder contraction. Manipulation of the acid stability of fat emulsion added to preprocessed foods could maximize satiety signaling and, in turn, help to reduce overconsumption of calories.
authors.affiliation: Wolfson Digestive Diseases Centre, QMC, Nottingham Univ. Hospital, Univ. of Nottingham, Nottingham NG7 2UH, UK.
authors.forename: Luca
authors.initials: L
authors.lastname: Marciani
authors.forename: Martin
authors.initials: M
authors.lastname: Wickham
authors.forename: Gulzar
authors.initials: G
authors.lastname: Singh
authors.forename: Debbie
authors.initials: D
authors.lastname: Bush
authors.forename: Barbara
authors.initials: B
authors.lastname: Pick
authors.forename: Eleanor
authors.initials: E
authors.lastname: Cox
authors.forename: Annette
authors.initials: A
authors.lastname: Fillery-Travis
authors.forename: Richard
authors.initials: R
authors.lastname: Faulks
authors.forename: Charles
authors.initials: C
authors.lastname: Marsden
authors.forename: Penny A
authors.initials: PA
authors.lastname: Gowland
authors.forename: Robin C
authors.initials: RC
authors.lastname: Spiller
mesh_terms: D000284:Administration, Oral; D000328:Adult; D002766:Cholecystokinin / Q000097:blood*; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D045703:Emulsifying Agents / Q000737:chemistry; D004655:Emulsions; D016473:Gallbladder Emptying / Q000187:drug effects*; D005744:Gastric Acid / Q000378:metabolism*; D005746:Gastric Emptying / Q000187:drug effects*; D005753:Gastric Mucosa / Q000378:metabolism; D006601:Hexoses / Q000737:chemistry; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D000069463:Olive Oil; D010938:Plant Oils / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D011136:Polysorbates / Q000737:chemistry; D019518:Postprandial Period; D012528:Satiety Response / Q000187:drug effects; D013270:Stomach / Q000187:drug effects*
chemical_list: D004042:Dietary Fats, Unsaturated; D045703:Emulsifying Agents; D004655:Emulsions; D006601:Hexoses; D000069463:Olive Oil; D010938:Plant Oils; D011136:Polysorbates; C018665:sorbitan monooleate; D002766:Cholecystokinin