Evaluation of platelet apoptosis markers in patients before and after myocardial revascularization

Abstract

Background. Cardiovascular diseases have remained the leading cause of death worldwide for more than 30 years. In the structure of circulatory diseases, the main place belongs to ischemic heart disease (IHD). Coronary artery bypass grafting is one of the main surgical methods for treatment of IHD. Predicting the postoperative outcome is complicated. Indicators of platelet apoptosis may become markers for predicting the risk of adverse outcomes. Aim. The aim of this study was to assess parameters of platelet apoptosis before and after coronary artery bypass surgery. Methods. The study included 14 patients who underwent coronary artery bypass grafting. Blood samples were taken immediately before and 4-5 days after the surgery and examined using Western blot analysis and flow cytofluorimetry. Platelets were stained with FITC-labeled Annexin V and also treated with antibodies to pro- and anti-apoptotic proteins (BAK, BAX, cytochrome c, caspase 3, BCL-2). Results. Study patients demonstrated a significant postoperative decrease in the markers of platelet apoptosis. Most of the patients (84.98%) showed a reduced Annexin V binding compared to the preoperative baseline, which indicated a decrease in the number of platelets during early apoptosis. Western blotting showed a decrease in major pro-apoptotic proteins (BAX, 87.76%; BAK, 91.18%), which also indicated a decrease in the number of apoptotic platelets. Conclusion. This pilot study showed that the functional parameters of platelets detected in patients with IHD differed from the characteristics of platelets from the same patients after myocardial revascularization. These results suggest that platelet metabolism is involved in the mechanism of IHD that reflects the disease severity. Future studies are needed to determine the potential prognostic role of platelet apoptosis in IHD patients.