The pathogenic mechanisms underlying
cardiovascular diseases involve significant alterations in myocardial gene and
protein expression. Proteomics analysis can define new
protein and
peptide changes associated with cardiac pathology, including
myocardial infarction. The aim of the present study was to analyze serum
proteome of patients with
ST-Elevation myocardial infarction (
STEMI). Serum samples were collected from
STEMI patients (age 65.0+/-10.3) at 5.3+/-2.7 hours after the onset of typical
chest pain and before initiating standard
therapy. Ten age- and sex-matched donors were used as controls. The samples were
albumin- and
IgG-depleted.
Isotope-coded affinity tag method was employed to label
cysteine residues and liquid chromatography-Tandem Mass Spectrometry analysis was performed to measure the labeled
proteins. Our proteomic approach identified increased levels of
vitamin D-binding protein precursor (VDB) in the serum of
STEMI patients when compared to control donors. Western blot analysis confirmed the increase in VDB
protein in
STEMI patients. Moreover, fresh thrombotic plaques, obtained during primary angioplasty, showed high expression of VDB
protein. Mechanistically, VDB
protein reduces platelet aggregation and prolongs coagulation time ex vivo.