Article

The involvement of circulating microparticles in inflammation, coagulation and cardiovascular diseases.

Department of Internal Medicine, University of Bologna and S Orsola-Malpighi Hospital, Italy.
The Canadian journal of cardiology (Impact Factor: 3.12). 04/2010; 26(4):140-5. DOI: 10.1016/S0828-282X(10)70371-8
Source: PubMed

ABSTRACT Microparticles (MPs) are small vesicles, ranging in size from 0.1 microm to 2 microm, originating from plasma membranes of endothelial cells, platelets, leukocytes and erythrocytes. MPs can transfer antigens and receptors to cell types that are different from their cell of origin. Circulating MPs provide a procoagulant aminophospholipid surface for the assembly of the specific enzymes of coagulation. Both tissue factor and phosphatidylserine are exposed on MP outer membranes. In addition, MPs can play a significant role in vascular function and inflammation by modulating nitric oxide and prostacyclin production in endothelial cells, and stimulating cytokine release and tissue factor induction in endothelial cells, as well as monocyte chemotaxis and adherence to the endothelium. Finally, increased levels of MPs have been found in the presence of acute coronary syndromes, ischemic stroke, diabetes, systemic and pulmonary hypertension, and hypertriglyceridemia. From a practical point of view, MPs could be considered to be important markers of cardiovascular risk, as well as surrogate end points for assessing the efficacy of new drugs and therapies.

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