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Licensed Unlicensed Requires Authentication Published by De Gruyter December 13, 2006

Initiation and progression of atherosclerosis – enzymatic or oxidative modification of low-density lipoprotein?

  • Michael Torzewski and Karl J. Lackner


Atherosclerosis is widely regarded as a chronic inflammatory disease that develops as a consequence of entrapment of low-density lipoprotein (LDL) in the arterial intima. Native LDL lacks inflammatory properties, so the lipoprotein must undergo biochemical alterations to become atherogenic. Among several other candidates, two different concepts of lipoprotein modification are propagated, the widespread oxidation hypothesis and the less common E-LDL hypothesis, which proposes that modification of LDL occurs through the action of ubiquitous hydrolytic enzymes (enzymatically modified LDL or E-LDL) rather than oxidation. By clearly distinguishing between the initiation and progression of atherosclerotic lesion development, this article reviews comparative studies of both types of lipoprotein modification and submits a viewpoint for discussion proposing that these lipoprotein modifications do not really compete, but rather complement one another. According to this concept, E-LDL might be more important for the initiation of atherosclerosis, while oxidative modification of LDL might be more helpful for diagnosis and prognosis of the disease.

Clin Chem Lab Med 2006;44:1389–94.

Corresponding author: Michael Torzewski, MD, Institute of Clinical Chemistry and Laboratory Medicine, Johannes Gutenberg University, 55101 Mainz, Germany Phone: +49-6131-175083, Fax: +49-6131-17475083,


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Received: 2006-6-2
Accepted: 2006-7-30
Published Online: 2006-12-13
Published in Print: 2006-12-1

©2006 by Walter de Gruyter Berlin New York

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