title: Microalga decreases plasma cholesterol by down-regulation of intestinal NPC1L1, hepatic LDL receptor, and HMG-CoA reductase.
abstract: The present study examined the cholesterol-lowering activity of algal powder (AP), algal lipids (AL), and algal residue (AR) and their interaction with genes of transporters, receptors, and enzymes involved in cholesterol absorption and metabolism. In this experiment, 48 hamsters were fed either control diet or one of the three experimental diets containing 2% AP, 1.0% AL, or 1.0% AR for 6 weeks. Plasma total cholesterol (TC) and non-high-density-lipoprotein-cholesterol (non-HDL-C) were significantly decreased in the AP and AL groups but not in the AR group compared with those in the control hamsters. It was found that the cholesterol-lowering activity of AP and AL was associated with down-regulation of hepatic 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase, low-density lipoprotein receptor (LDLR), and intestinal Niemann-Pick C1-like 1 (NPC1L1) transporter. It was concluded that the alga possessed the cholesterol-lowering activity and its lipids were the active ingredients. The mechanisms underlying the cholesterol-lowering activity of algae were mediated most likely by increasing the sterol excretion and decreasing the cholesterol absorption and synthesis.
authors.affiliation: Kwong Living Trust Food Safety and Analysis Laboratory and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China.
authors.forename: Jingnan
authors.initials: J
authors.lastname: Chen
authors.forename: Yue
authors.initials: Y
authors.lastname: Jiang
authors.forename: Ka Ying
authors.initials: KY
authors.lastname: Ma
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Chen
mesh_terms: D000818:Animals; D000924:Anticholesteremic Agents / Q000008:administration & dosage*; D002784:Cholesterol / Q000097:blood*; D006224:Cricetinae; D004195:Disease Models, Animal; D015536:Down-Regulation; D005260:Female; D055951:Functional Food / Q000032:analysis; D006801:Humans; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics* / Q000378:metabolism; D006937:Hypercholesterolemia / Q000097:blood / Q000178:diet therapy* / Q000235:genetics / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000201:enzymology; D008099:Liver / Q000378:metabolism; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D058086:Microalgae / Q000737:chemistry*; D011973:Receptors, LDL / Q000235:genetics* / Q000378:metabolism; D058009:Stramenopiles / Q000737:chemistry
chemical_list: D000924:Anticholesteremic Agents; D026901:Membrane Transport Proteins; D011973:Receptors, LDL; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases