Characterization of blood borne microparticles as markers of premature coronary calcification in newly menopausal women.

Autor: Jayachandran M; Department of Surgery and Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, 200 1st St. SW, Rochester, MN 55905, USA. jaya.m@mayo.edu, Litwiller RD, Owen WG, Heit JA, Behrenbeck T, Mulvagh SL, Araoz PA, Budoff MJ, Harman SM, Miller VM
Jazyk: angličtina
Zdroj: American journal of physiology. Heart and circulatory physiology [Am J Physiol Heart Circ Physiol] 2008 Sep; Vol. 295 (3), pp. H931-H938. Date of Electronic Publication: 2008 Jul 11.
DOI: 10.1152/ajpheart.00193.2008
Abstrakt: While the risk for symptomatic atherosclerotic disease increases after menopause, currently recognized risk factors do not identify ongoing disease processes in low-risk women. This study tested the hypothesis that circulating cell-derived microparticles may reflect disease processes in women defined as low risk by the Framingham risk score. The concentration and phenotype of circulating microparticles were evaluated in a cross-sectional study of apparently healthy menopausal women, screened for enrollment into the Kronos Early Estrogen Prevention Study. Microparticles were evaluated by flow cytometry, and coronary artery calcification (CAC) was scored using 64-slice computed tomography scanners. The procoagulant activity of isolated microparticles was determined with a sensitive fluorescent thrombin generation assay. Chronological age, body mass index, serum lipids, systolic blood pressure (Framingham risk score < 10%, range 1-3%), and high-sensitivity C-reactive protein did not differ significantly among women with low (0 < 35; range, 0.3-32 Agatston units) or high (>50; range, 93-315 Agatston units) CAC compared with women without calcification. The total concentration and percentage of microparticles derived from platelets and endothelial cells were greatest in women with high CAC scores. The thrombin-generating capacity of the isolated microparticles correlated with phosphatidylserine expression, which also was greatest in women with high CAC scores. The percentages of microparticles expressing granulocyte and monocyte markers were not significantly different among groups. Therefore, the characterization of platelet and endothelial microparticles may identify early menopausal women with premature CAC who would not otherwise be identified by the usual risk factor analysis.
Databáze: MEDLINE