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Updated: Jul 31, 2026

Cholesterol Efflux Assay
07:54

Cholesterol Efflux Assay

Published on: March 6, 2012

Libyan family with hypercholesterolemia and increased high-density lipoprotein cholesterol in plasma

D S Sheriff1, M el Fakhri, K Ghwarsha

  • 1Department of Biochemistry, Arab Medical University, Benghazi, Libya.

Clinical Chemistry
|December 1, 1994
PubMed

Insights

A genetic defect in hepatic lipase (HL) activity caused high HDL cholesterol in a family. This finding highlights HL

Area of Science:

  • Lipid metabolism
  • Cardiovascular genetics
  • Biochemistry

Background:

  • Genetic deficiencies in cholesteryl ester transport protein (CETP) and hepatic lipase (HL) are linked to hyperalpha-lipoproteinemia.
  • Familial hypercholesterolemia can result from various genetic defects affecting lipoprotein metabolism.

Observation:

  • A family of 11 members exhibited significantly elevated high-density lipoprotein (HDL) cholesterol levels with low plasma triglyceride concentrations.
  • Nine family members, including parents and children, displayed these distinct lipid profiles.

Findings:

  • Analysis revealed decreased heparin-releasable hepatic lipase (HL) activity as the probable cause for the elevated HDL2 fractions.
  • Lecithin:cholesterol acyltransferase (LCAT) activity, cholesteryl ester transfer, and lipoprotein lipase (LPL) activity were also assessed.

Implications:

  • A defect in HL activity can profoundly impact HDL metabolism and overall lipoprotein metabolism.
  • This study underscores the critical role of coordinated enzyme activity (HL, LCAT, LPL, CETP) in maintaining normal plasma lipoprotein homeostasis.
  • Altered HDL cholesterol metabolism, independent of low-density lipoprotein (LDL) issues, can lead to increased total serum cholesterol.

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