Title:Iron-Induced Fibrin in Cardiovascular Disease
VOLUME: 10 ISSUE: 3
Author(s):Boguslaw Lipinski and Etheresia Pretorius
Affiliation:Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag x323, ARCADIA, 0007, South Africa.
Keywords:Cardiovascular disease, fibrinogen, free radicals, inflammation, iron, parafibrin, thrombosis.
Abstract:Accumulating evidence within the last two decades indicates the association between cardiovascular disease
(CVD) and chronic inflammatory state. Under normal conditions fibrin clots are gradually degraded by the fibrinolytic
enzyme system, so no permanent insoluble deposits remain in the circulation. However, fibrinolytic therapy in coronary
and cerebral thrombosis is ineffective unless it is installed within 3-5 hours of the onset. We have shown that trivalent iron
(FeIII) initiates a hydroxyl radical-catalyzed conversion of fibrinogen into a fibrin-like polymer (parafibrin) that is
remarkably resistant to the proteolytic dissolution and thus promotes its intravascular deposition. Here we suggest that the
persistent presence of proteolysis-resistant fibrin clots causes chronic inflammation. We study the effects of certain
amphiphilic substances on the iron- and thrombin-induced fibrinogen polymerization visualized using scanning electron
microscopy. We argue that the culprit is an excessive accumulation of free iron in blood, known to be associated with
CVD. The only way to prevent iron overload is by supplementation with iron chelating agents. However, administration
of free radical scavengers as effective protection against persistent presence of fibrin-like deposits should also be
investigated to contribute to the prevention of cardiovascular and other degenerative diseases.
