title: Capsaicinoids lower plasma cholesterol and improve endothelial function in hamsters.
abstract: OBJECTIVE
  Capsaicinoids are the active compounds in chili pepper. The present study investigated the effect of capsaicinoids on plasma lipids, functionality of aorta including atherosclerotic plaque development, cholesterol absorption biomarker, fecal sterol excretion, and gene expression of major receptors, enzymes, and transporters involved in cholesterol metabolism.
  
  
  METHODS
  Hamsters were divided into five groups and fed a high-cholesterol diet containing 0 % (CON), 0.010 % (LD), 0.015 % (MD), 0.020 % (HD), and 0.030 % (VD) capsaicinoids, respectively, for 6 weeks. Plasma lipids were measured using the enzymatic kits, and the gene expression of transporters, enzymes, and receptors involved in cholesterol absorption and metabolism was quantified using the quantitative PCR. Endothelial function was assessed by measuring the acetylcholine-induced endothelium-dependent relaxations in aorta.
  
  
  RESULTS
  Capsaicinoids reduced plasma total cholesterol, non-high-density lipoprotein cholesterol, and triacylglycerols with high-density lipoprotein cholesterol being unaffected. All four experimental groups had a decrease in the atherosclerotic plaque compared with CON. Dietary capsaicinoids increased the fecal excretion of total acidic sterols possibly mediated by up-regulation of cholesterol 7α-hydroxylase and down-regulation of liver X receptor alpha. Plasma sterol analysis demonstrated that capsaicinoids decreased the ratio of plasma campesterol/cholesterol, suggesting they decreased cholesterol absorption. Capsaicinoids could improve the endothelium-dependent relaxations and reduce the endothelium-dependent contractions by inhibiting the gene expression of COX-2. However, no dose-dependent effect of capsaicinoids on these parameters was seen.
  
  
  CONCLUSIONS
  Capsaicinoids were beneficial in improving lipoprotein profile and aortic function in hamsters fed a high-cholesterol diet.
authors.affiliation: Food and Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Yin Tong
authors.initials: YT
authors.lastname: Liang
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Tian
authors.forename: Jing Nan
authors.initials: JN
authors.lastname: Chen
authors.forename: Cheng
authors.initials: C
authors.lastname: Peng
authors.forename: Ka Ying
authors.initials: KY
authors.lastname: Ma
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zuo
authors.forename: Rui
authors.initials: R
authors.lastname: Jiao
authors.forename: Ye
authors.initials: Y
authors.lastname: Lu
authors.forename: Yu
authors.initials: Y
authors.lastname: Huang
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Chen
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D002211:Capsaicin / Q000494:pharmacology*; D002212:Capsicum / Q000737:chemistry*; D002784:Cholesterol / Q000097:blood*; D002790:Cholesterol 7-alpha-Hydroxylase / Q000235:genetics / Q000378:metabolism; D006224:Cricetinae; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D000071518:Liver X Receptors; D008297:Male; D057093:Orphan Nuclear Receptors / Q000235:genetics / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D000071518:Liver X Receptors; D057093:Orphan Nuclear Receptors; D010936:Plant Extracts; D002784:Cholesterol; D002790:Cholesterol 7-alpha-Hydroxylase; D051546:Cyclooxygenase 2; D002211:Capsaicin