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.
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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
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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).
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All authors declare that there are no conflicts of interest.
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Yang, F., Ma, M., Xu, J. et al. An Egg-Enriched Diet Attenuates Plasma Lipids and Mediates Cholesterol Metabolism of High-Cholesterol Fed Rats. Lipids 47, 269–277 (2012). https://doi.org/10.1007/s11745-011-3646-x
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DOI: https://doi.org/10.1007/s11745-011-3646-x
Keywords
- Egg-enriched diet
- Cholesterol
- Plasma lipids
- mRNA expression