title: Low protein Z plasma levels are independently associated with acute coronary syndromes.
abstract: Protein Z (PZ) is a single chain vitamin-K-dependent glycoprotein synthesized by the liver. Studies in vivo and in vitro suggest that PZ plays an important role in inhibiting coagulation as it serves as cofactor for the inactivation of factor Xa by forming a complex with the plasma PZ-dependent protease inhibitor. Recently, conflicting findings on plasma PZ levels in patients with ischemic stroke have been published. Aim of our study was to investigate the role of PZ in acute coronary syndromes (ACS). PZ plasma levels were determined in 223 (189 M; 34 F) patients with ACS referring to the Coronary Intensive Therapy Unit of University of Florence and in 265 (219 M; 46 F) healthy subjects. Patients under oral anticoagulation treatment as well as subjects with positivity for antiphospholipid antibodies were excluded. None had liver or kidney dysfunction. The mean PZ plasma level was lower in patients (1508 +/- 730 ng/mL) than in controls (1728 +/- 594 ng/mL) (p < 0.0001). PZ levels below the 5th percentile (565 ng/mL) of normal values distribution in control subjects were found in 15.7% of patients and in 4.9% of controls (p <0.0001). At multivariate analysis, PZ levels below 565 ng/mL were associated with ACS (OR=3.3; 99%CI 1.1-9.7; p = 0.004). The contemporary presence of low PZ levels and smoking habit leads to an increased risk of ACS (OR=9.5; 99%CI 2.4-37.2; p < 0.0001). In conclusion, our results suggest a possible role of PZ in the occurrence of arterial thrombosis.
authors.affiliation: Department of Medical and Surgical Critical Care, Section of Clinical Medicine and Cardiology, University of Florence, and Thrombosis Center, Azienda Ospedaliera Careggi, Viale G. Morgagni 85, 50134 Florence, Italy. frasofi@hotmail.com
authors.forename: Sandra
authors.initials: S
authors.lastname: Fedi
authors.forename: Francesco
authors.initials: F
authors.lastname: Sofi
authors.forename: Daria
authors.initials: D
authors.lastname: Brogi
authors.forename: Irene
authors.initials: I
authors.lastname: Tellini
authors.forename: Francesca
authors.initials: F
authors.lastname: Cesari
authors.forename: Ilaria
authors.initials: I
authors.lastname: Sestini
authors.forename: Alessandra
authors.initials: A
authors.lastname: Gazzini
authors.forename: Marco
authors.initials: M
authors.lastname: Comeglio
authors.forename: Rosanna
authors.initials: R
authors.lastname: Abbate
authors.forename: Gian Franco
authors.initials: GF
authors.lastname: Gensini
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000097:blood / Q000209:etiology; D001798:Blood Proteins / Q000032:analysis* / Q000502:physiology; D016022:Case-Control Studies; D003327:Coronary Disease / Q000097:blood* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000209:etiology; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D013927:Thrombosis / Q000097:blood / Q000209:etiology
chemical_list: D001798:Blood Proteins; C026080:plasma protein Z