Cholesterol-lowering effects and potential mechanisms of chitooligosaccharide capsules in hyperlipidemic rats

Background: Chitooligosaccharide (COS) has shown potential antihyperlipidemic activity in a few studies as a functional Food. Method: We investigated the cholesterol-lowering effect and potential mechanisms of chitooligosaccharide capsules (COSTC) in male SD rats fed a high-fat diet. Results: COSTC could ameliorate serum lipid levels. Simultaneously, the cholesterol-lowering effect is probably attributed to its role in two pathways: upregulating the gene expression and activity of cholesterol 7 alpha-hydroxylase (CYP7A1), liver X receptor alpha (LXRA), and peroxisome proliferation activated receptor-a (PPARa), which facilitates the conversion of cholesterol into bile acid; downregulating the gene expression and activity of enzymes including 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) and sterol-responsive element binding protein-2 (SREBP2) and upregulating the low-density lipoprotein receptor (I,DLR) to reduce the denovo synthesis of cholesterol. Conclusion: Studies have suggested that COSTC has potential usefulness as a natural supplement or functional food for preventing and treating hyperlipidemia.