| Objective:Coronary artery disease (CAD) is one of the most popular CVDs and caused 8.14 million deaths (16.8%) globally. A number of molecular biologic studies concerning CAD have been reported, which may bring many new ideas about the mechanism of CAD. In fact, more than 100 single nucleotide variants (SNVs) that associated with CAD have been confirmed by genome wide association study (GWAS). Accordingly, many researches have confirmed the relationship between changes of some plasma proteins and the pathological process of CAD such as inflammation, platelet activation and coagulation. However, the proteins involved in the process of CAD, particularly the CAD patients requiring coronary artery bypass grafting (CABG), must be complicated and have not been clearly detected yet. The purpose of this paper is to figure out the differences of proteins in blood between the patients with-and without severe coronary artery lesions which needs bypass grafting.Methods:From April 22,2013 to September 24,2015,320 patients who had diagnostic coronary angiography were enrolled in the research and divided into two groups as CABG (160 patients with CAD and undergoing CABG) and Control (control group, n=160). Patients in CABG group were diagnosed as triple-vessel with or without left main CAD by coronary angiography and therefore underwent CABG procedure. The other half of patients was ruled out of CAD with angiography. Candidates with neurological disease (eg. cerebral vascular accident), severe pulmonary disease, renal dysfunction, liver dysfunction, active inflammation, infection, coagulation disorders, atrial fibrillation history or thyroid dysfunction were excluded. Blood samples for proteomics research were collected before the CABG or the angiographic procedure and immediately centrifuged at 3500 rpm for 15 minutes. The plasma was collected carefully and stored at -80 degree until the analysis was carried out. The pooled plasma samples of 20 males and 20 females in each group were marked with CABGM (CABG group, male), CABGF (CABG group, female), CM (control group, male) or CF (control group, female), respectively and analyzed with iTRAQ technique. Proteins identification was performed by using Mascot search engine. The quantitative protein ratios were weighted and normalized by the median ratio in Mascot. The fold changes of>1.2 and p value less than 0.05 were considered as significant. With the plasma samples from CABG group (n=120, male=61) and control (n=120, male=60), six ones in the proteins identified by iTRAQ as significant were then verified by using human enzyme-linked immunosorbent assay (ELISA) Kit.Result:From iTRAQ analysis,544 proteins were detected, in which 35 proteins were up-regulated and 41 were down-regulated (CABG vs. control, p<0.05). Coagulation factor XIII B chain (F13B), platelet factor 4 (PF4) and secreted frizzled-related protein 1 (sFRPl) were up-regulated, vitamin D-binding protein (DBP), glyceraldehyde-3-phosphate dehydrogenase (G3PDH) and properdin (CFP) were down-regulated (p<0.05). In ELISA tests, the plasma level of CFP, DBP, PF4 and sFRPl were up-regulated significantly (CABG vs. control, p<0.05). DBP, PF4 and sFRPl had a positive relation with CAD diagnosis (p<0.05) and myocardial infarction history (p<0.05). Areas under the curve of ROC tests for PF4 are 0.858. The best differential point of PF4 is 1021.00 with sensitivity of 77.4% and specificity of 93.3% (YI=0.707).Conclusion:We have found 76 proteins differentially expressed in plasma samples from CAD patients and control. Proteins involved in different physiological processes such as coagulation, platelet activation, complement pathway and Wnt/fz signal-transduction pathway may play an important role in the progress of CAD. PF4 and sFRPl were significantly up-regulated in CAD patients. ROC test showed that PF4 could act as a biomarker in the clinical diagnosis of CAD.
|
PDF Full Text Request