Location: Healthy Processed Foods Research
Title: Peptides identified in soybean protein increase plasma cholesterol in mice on hypercholesterolemic diets Authors
|Zhang, Huijuan -|
|Zhang, Hui -|
|Wang, Jing -|
|Zhong, Fang -|
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 12, 2013
Publication Date: August 12, 2013
Citation: Zhang, H., Bartley, G.E., Zhang, H., Wang, J., Fagerquist, C.K., Zhong, F., Yokoyama, W.H. 2013. Peptides identified in soybean protein increase plasma cholesterol in mice on hypercholesterolemic diets. Journal of Agricultural and Food Chemistry. 61(35):8389-8395. Interpretive Summary: Peptides identified by other researchers that were purported to have potential cholesterol reducing properties based on in vitro testing were tested in mice fed high fat, hyper-Cholesterolemic diets. However, the two peptides increased plasma cholesterol in mice and these physiological effects were supported by changes in expression of genes related to cholesterol and bile acid metabolism. The research suggests that the peptides were bioactive but did not lower cholesterol.
Technical Abstract: The in vitro micellar cholesterol displacement assay has been used to identify peptides that may potentially reduce cholesterol in vivo. We tested two of these peptides, LPYPR and WGAPSI, derived from soybean protein (SP) that have been reported to displace cholesterol from micelles by feeding them as part of a hypercholesterolemic diet to mice for 3 weeks. Except reduction of very low-density lipoprotein cholesterol (VLDL-C) and triglyceride concentrations, the peptide containing diets increased plasma cholesterol concentration with increasing dose of the peptides. Mice fed diets supplemented with the peptides also had lower fecal bile acid excretion. The mRNA level of the genes for cholesterol and bile acid metabolism, CYP51, LDLR, and CYP7A1, were up regulated in mice fed diets supplemented with peptides except the group fed the low dose of WGAPSI.