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Updated: May 20, 2026
07:54
Cholesterol Efflux Assay
Published on: March 6, 2012
Trans-intestinal cholesterol efflux is not mediated through high density lipoprotein
Carlos L J Vrins1, Roelof Ottenhoff2, Karin van den Oever3
1Department of Medical Biochemistry, Amsterdam, The Netherlands; AMC Tytgat Institute, Academic Medical Center, Amsterdam, The Netherlands.
Journal of Lipid Research
|July 18, 2012
Summary
High-density lipoprotein (HDL) does not play a significant role in transintestinal cholesterol efflux (TICE) in mice. This finding challenges the assumed involvement of HDL in direct plasma cholesterol delivery to the intestine for excretion.
Area of Science:
- Metabolic diseases
- Cardiovascular research
- Cholesterol metabolism
Background:
- Transintestinal cholesterol efflux (TICE) is a key pathway for cholesterol excretion.
- The specific plasma cholesterol donor facilitating TICE remains unidentified.
- High-density lipoprotein (HDL) is a potential, yet unconfirmed, contributor to TICE.
Purpose of the Study:
- To investigate the role of HDL in mediating TICE.
- To determine if HDL directly delivers plasma cholesterol to the intestine for excretion.
Main Methods:
- Utilized ATP-binding cassette protein A1 deficient (Abca1(-/-)) mice lacking HDL and wild-type (WT) mice.
- Administered radiolabeled cholesterol via chylomicron-like emulsion particles.
- Administered radiolabeled cholesterol via HDL in WT and Abca1(-/-)×Sr-b1(-/-) mice.
Main Results:
- TICE occurred in both WT and Abca1(-/-) mice injected with cholesterol emulsion, indicating HDL is not essential for this process.
- Intestinal uptake and secretion of cholesterol from HDL were not observed in WT or Abca1(-/-)×Sr-b1(-/-) mice.
- HDL did not contribute to TICE in the studied mouse models.
Conclusions:
- HDL is not a significant mediator of transintestinal cholesterol efflux in mice.
- The findings suggest HDL does not directly deliver plasma cholesterol to the intestine for excretion via TICE.
- Further research is needed to identify the precise cholesterol donor involved in TICE.
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