title: Satiety and memory enhancing effects of a high-protein meal depend on the source of protein.
abstract: OBJECTIVE
  High- protein diets have become increasingly popular with various touted benefits. However, the extent to which protein quantity and source affects cognitive functioning through altering postprandial amino acid profiles has not been investigated. Further, whether all protein sources are similarly anorexigenic is uncertain. The objective of this study was to determine the influence of protein level and source on Barnes maze performance, satiety and plasma amino acid levels in male Sprague-Dawley rats.
  
  
  METHODS
  Rats were entrained to a meal-feeding schedule consisting of a 30 minutes meal, equivalent to 20% of average daily intake, one hour into the dark phase then ad libitum access to food for 5 h. On test days, rats received one of three isocaloric diets as their first meal, hereafter referred to as Egg White (EW), Wheat Gluten (WG), or Basal, and then were measured for cognitive performance, feeding behavior, or plasma amino acid levels via jugular catheter. Percentage energy from protein was 35% for both EW and WG and 20% for Basal with equal amounts provided by EW and WG proteins.
  
  
  RESULTS
  Rats provided EW performed similarly to Basal on the Barnes maze, whereas WG performed worse. EW increased satiety, whereas WG reduced satiety relative to Basal. Both EW and WG increased postprandial concentrations of large neutral and branched chain amino acids relative to Basal, but in EW, concentrations were slower to peak, and peaked to a higher level than WG.
  
  
  CONCLUSIONS
  Results demonstrate the importance of protein source for cognition and satiety enhancing effects of a high-protein meal.
authors.affiliation: a Beckman Institute for Advanced Science and Technology , Urbana, IL , USA.|b Division of Nutritional Sciences , University of Illinois at Urbana-Champaign , Urbana, IL , USA.
authors.forename: Kristy
authors.initials: K
authors.lastname: Du
authors.affiliation: c Department of Nutrition , University of North Carolina Greensboro , Greensboro, NC , USA.
authors.forename: Edward
authors.initials: E
authors.lastname: Markus
authors.affiliation: c Department of Nutrition , University of North Carolina Greensboro , Greensboro, NC , USA.
authors.forename: Mariel
authors.identifier: http://orcid.org/0000-0002-6738-2969
authors.initials: M
authors.lastname: Fecych
authors.affiliation: a Beckman Institute for Advanced Science and Technology , Urbana, IL , USA.|b Division of Nutritional Sciences , University of Illinois at Urbana-Champaign , Urbana, IL , USA.|d Department of Psychology , University of Illinois at Urbana-Champaign , Champaign, IL USA.
authors.forename: Justin S
authors.initials: JS
authors.lastname: Rhodes
authors.affiliation: b Division of Nutritional Sciences , University of Illinois at Urbana-Champaign , Urbana, IL , USA.|c Department of Nutrition , University of North Carolina Greensboro , Greensboro, NC , USA.|e Department of Animal Sciences , University of Illinois at Urbana-Champaign , Champaign, IL USA.
authors.forename: J Lee
authors.initials: JL
authors.lastname: Beverly
mesh_terms: D000596:Amino Acids / Q000097:blood / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose; D000073600:Diet, High-Protein / Q000523:psychology*; D004044:Dietary Proteins / Q000494:pharmacology; D015387:Egg Proteins, Dietary / Q000494:pharmacology*; D002149:Energy Intake; D005247:Feeding Behavior; D005983:Glutens / Q000494:pharmacology*; D007858:Learning; D008297:Male; D018782:Maze Learning; D008568:Memory / Q000187:drug effects*; D019518:Postprandial Period; D051381:Rats; D017207:Rats, Sprague-Dawley; D012527:Satiation
chemical_list: D000596:Amino Acids; D001786:Blood Glucose; D004044:Dietary Proteins; D015387:Egg Proteins, Dietary; D005983:Glutens
keywords: Cognitive function; Egg white protein; Food intake; Learning; Memory; Protein type; Satiety; Wheat gluten protein