Related Experiment Video
Updated: Jul 5, 2026
07:54
Cholesterol Efflux Assay
Published on: March 6, 2012
Peroxisome proliferator-activated receptor alpha agonists regulate cholesterol ester transfer protein
Thomas P Beyer1, Yanqun Chen, Regina K Porter
1Cardiovascular Research, Lilly Research Laboratories, Eli Lilly & Company, Indianapolis, IN 46285, USA.
Lipids
|May 16, 2008
Summary
Peroxisome proliferator-activated receptor alpha (PPARalpha) agonists enhance cholesterol ester transfer protein (CETP) expression and activity. This finding is crucial for understanding HDL cholesterol homeostasis regulation.
Area of Science:
- Biochemistry
- Molecular Biology
- Pharmacology
Background:
- Peroxisome proliferator-activated receptor alpha (PPARalpha) is a nuclear receptor regulating lipid metabolism.
- Cholesterol ester transfer protein (CETP) influences high-density lipoprotein (HDL) particle modification.
- Human plasma CETP activity shows an inverse correlation with HDL cholesterol levels.
Purpose of the Study:
- To investigate the effect of PPARalpha agonists on CETP expression and activity.
- To elucidate the role of PPARalpha in regulating CETP-mediated lipid metabolism.
Main Methods:
- Utilized a human CETP transgenic animal model.
- Administered PPARalpha agonists (fenofibrate, LY970, Wy14643) to animal models and HepG2 cells.
- Measured CETP mRNA, protein levels, and enzymatic activity.
Main Results:
- PPARalpha agonists significantly increased CETP mRNA, protein, and activity in both transgenic and hamster models.
- Fenofibrate demonstrated a dose-dependent upregulation of endogenous CETP in hamsters.
- Overexpression and agonist treatment of PPARalpha in HepG2 cells elevated CETP mRNA.
Conclusions:
- PPARalpha agonists upregulate CETP expression and activity.
- PPARalpha plays a significant role in mediating HDL cholesterol homeostasis through CETP regulation.
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