title: Dietary soybean peptides containing a low-molecular fraction can lower serum and liver triglyceride levels in rats.
abstract: We investigated the effects of dietary soybean peptides, particularly low-molecular-weight peptides, on serum and hepatic concentrations of lipids in rats. Soybean protein isolate (SPI) was digested with protease to produce low-molecular-weight peptides (LD) or a mixture of high- and low-molecular-weight peptides (HLD). Rats were fed diets containing 20% casein, SPI, LD or HLD as a nitrogen source, with or without 0.5% cholesterol, for 2 wk. Next, rats were fed cholesterol-free diets containing 0%, 5%, 10%, or 20% LD at the expense of casein for 2 wk. Serum triglyceride levels were the lowest in the LD group, and liver triglyceride levels were significantly lower in rats fed SPI and LD/HLD diets than in those fed casein diets, both in the presence and absence of dietary cholesterol. In addition, dietary LD significantly lowered serum and liver triglyceride levels in a dose-dependent manner. These results suggest that low-molecular-weight soybean peptides have a potent hypotriglyceridemic effect and may be beneficial for improving lipid metabolism.
authors: Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 2)  Department of Nutrition, Faculty of Nursing and Nutrition, University of Nagasaki, Nagasaki 851-2195, Japan.
authors: Shizuka
authors: S
authors: Tamaru
authors: Takayuki
authors: T
authors: Kurayama
authors: Masanobu
authors: M
authors: Sakono
authors: Nobuhiro
authors: N
authors: Fukuda
authors: Toshihiro
authors: T
authors: Nakamori
authors: Hitoshi
authors: H
authors: Furuta
authors: Yasuo
authors: Y
authors: Nagata
authors: Kazunari
authors: K
authors: Tanaka
mesh_terms: D000818:Animals; D002364:Caseins / Q000008:administration & dosage; D002784:Cholesterol / Q000097:blood; D002791:Cholesterol, Dietary / Q000008:administration & dosage; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000378:metabolism; D010455:Peptides / Q000008:administration & dosage*; D051381:Rats; D017207:Rats, Sprague-Dawley; D030262:Soybean Proteins / Q000008:administration & dosage*; D013025:Glycine max / Q000737:chemistry*; D014280:Triglycerides / Q000097:blood / Q000378:metabolism*
chemical_list: D002364:Caseins; D002791:Cholesterol, Dietary; D010455:Peptides; D030262:Soybean Proteins; D014280:Triglycerides; D002784:Cholesterol; D010447:Peptide Hydrolases