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Updated: May 11, 2026

Cholesterol Efflux Assay
07:54

Cholesterol Efflux Assay

Published on: March 6, 2012

In vivo tissue cholesterol efflux is reduced in carriers of a mutation in APOA1

Adriaan G Holleboom1, Lily Jakulj, Remco Franssen

  • 1Department of Vascular Medicine, Academic Medical Center, Amsterdam, The Netherlands.

Journal of Lipid Research
|May 8, 2013
PubMed

Insights

High-density lipoprotein (HDL) cholesterol transport is reduced in individuals with APOA1 mutations. Non-HDL pathways significantly contribute to reverse cholesterol transport despite low HDL levels.

Area of Science:

  • Cardiovascular Biology
  • Metabolic Pathways
  • Lipid Metabolism

Background:

  • High-density lipoprotein (HDL) is crucial for atheroprotection, primarily via reverse cholesterol transport (RCT).
  • Mutations in Apolipoprotein A1 (APOA1) lead to significantly reduced plasma HDL cholesterol (HDL-c).

Purpose of the Study:

  • To investigate in vivo cholesterol fluxes through the RCT pathway in patients with APOA1 mutations causing low HDL-c.
  • To quantify tissue cholesterol efflux (TCE) in carriers of APOA1 mutations compared to healthy controls.

Main Methods:

  • Seven carriers of the APOA1 L202P mutation and seven controls received a (13)C2-cholesterol infusion.
  • Plasma and erythrocyte cholesterol enrichment was measured.
  • A three-compartment SAAM-II model was used to calculate tissue cholesterol efflux (TCE).

Main Results:

  • TCE was significantly reduced by 19% in APOA1 mutation carriers (4.6 ± 0.8 mg/kg/h) compared to controls (5.7 ± 0.7 mg/kg/h).
  • Fecal (13)C recovery and sterol excretion did not differ significantly between carriers and controls.
  • Despite severely reduced HDL-c, residual TCE was observed in carriers.

Conclusions:

  • HDL contributes to tissue cholesterol efflux in humans, as evidenced by reduced TCE in APOA1 mutation carriers.
  • Non-HDL pathways play a significant role in reverse cholesterol transport, compensating for reduced HDL function.

Keywords:
fecal sterol excretiongeneticshigh density lipoproteinreverse cholesterol transport

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