Hypocholesterolemic effects of Lactobacillus plantarum KCTC3928 by increased bile acid excretion in C57BL/6 mice
Received 13 November 2008; accepted 17 April 2009. published online 20 August 2009.
Abstract
Objective
We doubly coated Lactobacillus plantarum KCTC3928 with proteins and polysaccharide compounds to enhance its acid and bile resistance. The present study investigated the hypocholesterolemic effects of double-coated L. plantarum KCTC3928 in C57BL/6 mice fed a high-fat diet. The effects of live and dead bacteria were compared.
Methods
Six-week-old C57BL/6 male mice were divided into three groups: the control group was fed no L. plantarum KCTC3928, and the two treatment groups were orally fed live or dead L. plantarum KCTC3928 daily. Plasma and liver cholesterol and lipid levels, fecal bile acid, and gene and protein expressions were measured.
Results
Low-density lipoprotein cholesterol and plasma triacylglycerol levels were significantly lower in the group fed live bacteria, by 42% and 32%, respectively (P<0.05), and fecal bile acid excretion was accelerated (+45%). Expression of the low-density lipoprotein receptor and 3-hydroxy-3-methylglutaryl coenzyme A reductase were marginally affected by the feeding of coated cells; however, the gene expression and protein levels of CYP7A1 were significantly upregulated after live L. plantarum KCTC3928 feeding (+80% for mRNA and +60% for protein expression).
Conclusion
Double-coated live L. plantarum KCTC3928 may have hypocholesterolemic effects in mice primarily due to induction of fecal bile acid secretion followed by increased degradation of hepatic cholesterol into bile acids. Studies in humans should confirm the effects in the future.
aDivision of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Institute of Biomedical Sciences and Food Safety, Korea University, Seoul, South Korea
bR&D Center of Cellbiotech Co. Ltd., Gyunggi-Do, South Korea
ABSTRACT