Dietary soy protein isolate and its undigested high molecular fraction upregulate hepatic ATP-binding cassette transporter G5 and ATP-binding cassette transporter G8 mRNA and increase biliary secretion of cholesterol in rats.
Dietary soy protein isolate (SPI) and its undigested high molecular fraction (HMF) exhaustively digested with proteases, compared with casein (CAS), significantly reduced serum and liver cholesterol concentration in rats. Biliary excretion of cholesterol was significantly higher in rats fed SPI and HMF than in those fed CAS. Hepatic expression of ATP-binding cassette transporter G5 (ABCG5) and ATP-binding cassette transporter G8 (ABCG8) mRNA was significantly higher in rats fed SPI and HMF than in those fed CAS. These observations suggest that increased biliary excretion of cholesterol in SPI and HMF groups is caused by the enhanced expression of Abcg5/Abcg8.
Ikeda
Ikuo
I
Laboratory of Food and Biomolecular Science, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan. iikeda@biochem.tohoku.ac.jp
Kudo
Mariko
M
Hamada
Tadateru
T
Nagao
Koji
K
Oshiro
Yoko
Y
Kato
Masaki
M
Sugawara
Takashi
T
Yamahira
Takashi
T
Ito
Hiroko
H
Tamaru
Shogo
S
Sato
Masao
M
Imaizumi
Katsumi
K
Nagaoka
Satoshi
S
Yanagita
Teruyoshi
T
D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D000071019:ATP Binding Cassette Transporter, Subfamily G, Member 8; D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D000818:Animals; D001646:Bile / Q000378:metabolism*; D002784:Cholesterol / Q000032:analysis / Q000097:blood / Q000378:metabolism*; D004044:Dietary Proteins / Q000008:administration & dosage*; D004063:Digestion; D008074:Lipoproteins / Q000235:genetics*; D008099:Liver / Q000737:chemistry; D008297:Male; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D030262:Soybean Proteins / Q000008:administration & dosage* / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D000071019:ATP Binding Cassette Transporter, Subfamily G, Member 8; D018528:ATP-Binding Cassette Transporters; C480692:Abcg5 protein, rat; C480693:Abcg8 protein, rat; D004044:Dietary Proteins; D008074:Lipoproteins; D012333:RNA, Messenger; D030262:Soybean Proteins; D002784:Cholesterol; D010447:Peptide Hydrolases