title: A soybean peptide isolate diet promotes postprandial carbohydrate oxidation and energy expenditure in type II diabetic mice.
abstract: The aim of the present study was to determine the effects of dietary proteins on the oxidation of dietary carbohydrate and lipids in type II diabetic mice. KK-A(y) strain mice were provided free access to a high fat diet (30% of energy as fat) for an initial 4-wk period to induce diabetes. To reduce body weight gain, the mice were subsequently fed restrictive isoenergetic and isonitrogenous diets (35% of energy as protein and 5% as fat) based on either casein or soy protein isolate hydrolysate (SPI-H) for 4 wk. To measure exogenous carbohydrate and lipid oxidation, the mice were fed a diet containing (13)C-glucose or (13)C-triolein while they were in a respiratory chamber for 72 h. Postprandial energy expenditure was higher in the SPI-H than in the casein group; this difference was due to an increase in postprandial exogenous and endogenous carbohydrate oxidation. There were no differences in 24-h energy expenditure between dietary groups. Oxidation of exogenous carbohydrate tended to be higher (P = 0.054) in the SPI-H group during the 24 h of measurement. Fecal excretion of (13)C-glucose was lower but the excretion of lipid was higher in mice fed the SPI-H diet than in casein-fed mice. These results indicate that in type II diabetic mice, dietary SPI-H not only inhibits the absorption of dietary lipids and increases the absorption of dietary carbohydrates but also augments postprandial energy expenditure, which is accompanied by a postprandial increase in oxidation of dietary carbohydrates.
authors.affiliation: Department of Food and Nutrition, School of Life Studies, Sugiyama Jogakuen University, Nagoya 464-8662, Japan. kengo@food.sugiyama-u.ac.jp
authors.forename: Kengo
authors.initials: K
authors.lastname: Ishihara
authors.forename: Shinichi
authors.initials: S
authors.lastname: Oyaizu
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Fukuchi
authors.forename: Wataru
authors.initials: W
authors.lastname: Mizunoya
authors.forename: Kikumi
authors.initials: K
authors.lastname: Segawa
authors.forename: Miki
authors.initials: M
authors.lastname: Takahashi
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Mita
authors.forename: Yoko
authors.initials: Y
authors.lastname: Fukuya
authors.forename: Tohru
authors.initials: T
authors.lastname: Fushiki
authors.forename: Kyoden
authors.initials: K
authors.lastname: Yasumoto
mesh_terms: D000818:Animals; D001835:Body Weight; D002247:Carbon Isotopes / Q000378:metabolism; D002364:Caseins / Q000008:administration & dosage; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D004040:Dietary Carbohydrates / Q000378:metabolism* / Q000493:pharmacokinetics; D004041:Dietary Fats / Q000378:metabolism / Q000493:pharmacokinetics; D004044:Dietary Proteins / Q000008:administration & dosage*; D002149:Energy Intake; D004734:Energy Metabolism; D005243:Feces / Q000737:chemistry; D007408:Intestinal Absorption; D008297:Male; D051379:Mice; D010084:Oxidation-Reduction; D030262:Soybean Proteins / Q000008:administration & dosage*; D014304:Triolein / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics
chemical_list: D002247:Carbon Isotopes; D002364:Caseins; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D030262:Soybean Proteins; D014304:Triolein