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Lipids

, Volume 47, Issue 3, pp 269–277 | Cite as

An Egg-Enriched Diet Attenuates Plasma Lipids and Mediates Cholesterol Metabolism of High-Cholesterol Fed Rats

  • Fang Yang
  • Meihu Ma
  • Jia Xu
  • Xiufang Yu
  • Ning Qiu
Original Article

Abstract

We investigated the influence of an egg-enriched diet on plasma, hepatic and fecal lipid levels and on gene expression levels of transporters, receptors and enzymes involved in cholesterol metabolism. Sprague–Dawley rats fed an egg-enriched diet had lower plasma triglycerides, total cholesterol, low density lipoprotein (LDL)-cholesterol, hepatic triglyceride, and cholesterol concentrations, and greater plasma high-density lipoprotein cholesterol concentration, fecal neutral sterol and bile acid concentrations than those fed a plain cholesterol diet. Chicken egg yolk had no effect on sterol 12α-hydroxylase and sterol 27α-hydroxylase; but upregulated mRNA levels of hepatic LDL-receptor, cholesterol 7α-hydroxylase (CYP7A1) and lecithin cholesterol acyltransferase, and downregulated hepatic hydroxymethylglutaryl-(HMG)-CoA reductase and acyl-CoA:cholesterol acyltransferase (ACAT) after 90 days. Modification of the lipoprotein profile by an egg-enriched diet was mediated by reducing de novo cholesterol synthesis and enhancing the excretion of fecal cholesterol, via upregulation of CYP7A1 and the LDL receptor, and downregulation of HMG-CoA reductase and ACAT.

Keywords

Egg-enriched diet Cholesterol Plasma lipids mRNA expression 

Abbreviations

CVD

Cardiovascular disease

PC

Phosphatidylcholine

SM

Sphingomyelin

SHR

Spontaneously hypertensive rats

RT-qPCR

Real time quantitative polymerase chain reaction

OV

Ovomucin

CCG

Common control group

CLG

Cholesterol group

EYG

Egg yolk group

WEG

Whole egg group

HBA

Total bile acid

apoB

Apolipoprotein-B-100

apoA1

Apolipoprotein-A-1

HE

Hematoxylin and eosin

GAPDH

Glyceraldehyde-3-phosphate dehydrogenase

HMG-CoA R

Hydroxymethylglutaryl CoA reductase

LDLr

LDL receptor

CYP7A1

Cholesterol 7α-hydroxylase

CYP27A1

Sterol 27α-hydroxylase

CYP8B1

Sterol 12α-hydroxylase

ACAT

Acyl-CoA:cholesterol acyltransferase

LCAT

Lecithin cholesterol acyltransferase

EWP

Egg white protein

Notes

Acknowledgments

We duly acknowledge the financial support received from the earmarked fund for Modern Agro-industry Technology Research System (Project Code No.: nycytx-41-g22).

Conflict of interest

All authors declare that there are no conflicts of interest.

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Copyright information

© AOCS 2012

Authors and Affiliations

  • Fang Yang
    • 1
  • Meihu Ma
    • 1
  • Jia Xu
    • 2
  • Xiufang Yu
    • 1
  • Ning Qiu
    • 1
  1. 1.National R&D Center for Egg Processing, College of Food Science and TechnologyHuazhong Agricultural UniversityWuhanPeople’s Republic of China
  2. 2.College of Animal Science and TechnologyHuazhong Agricultural UniversityWuhanPeople’s Republic of China

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