isoDGR fibronectin and CD9 association with MACE & aging in carotid endarterectomy patients

Abstract

This study has identified two potential indicators that could help determine which patients still remain at high risk of life threatening events after they had plaque removal surgery in their carotid arteries. Every year, 17.6 million people worldwide die of the consequences of atherosclerosis. Patients with atherosclerosis suffer from plaques, a fatty build up, in their arteries. These plaques narrow the artery which makes it harder for blood to flow through. If a blood clot forms, it can block the blood flow and thereby cause life-threatening events such as a stroke or heart attack. With surgery, the plaque can be removed from the arteries. Removal of the plaque lowers the risk of a life-threatening event. However, a certain group of patients still remains at high risk of life-threatening events. The newest European medicine guidelines recommend extra treatment for these high risk patients after plaque removal surgery. However, right now, no tests are available that can determine who the high risk patients are. To develop a test we need to find risk-indicators, also called biomarkers. A possible biomarker is isoDGR fibronectin. The fibronectin protein is the glue between cells. However, because of protein aging, fibronectin can become isoDGR fibronectin. Previous studies showed that isoDGR fibronectin is involved in atherosclerosis. Another possible biomarker source are Extracellular vesicles (EVs). These EVs are very small vesicles that are released by all cells in the body and are a form of cell communication. CD9 is a protein attached to the EVs. Therefore, if we measure CD9 we know how many EVs there are. Next to isoDGR fibronectin, previous studies showed that EVs are also involved in atherosclerosis. Even though we know that the possible biomarkers, isoDGR fibronectin and CD9, are involved in atherosclerosis, we do not know if they can determine which patients are high-risk patients after plaque removal surgery. Therefore, we further investigated the two possible biomarkers in this study. We measured the biomarkers in the blood of patients that had all undergone plaque removal surgery. Then we compared patients that experienced a life threatening event, withing 3 years after the surgery, and patients who did not. Our results showed that patients who had a life threatening event, had less isoDGR fibronectin and CD9 in their blood. We also investigated whether the amount of biomarker depends on the age of the patient. We found that older patients had more isoDGR fibronectin and less CD9 in their blood compared to younger patients. Taken together, we now know more about atherosclerosis and we think that isoDGR fibronectin and CD9 can be possible biomarkers to identify which patients will get a life threatening event after plaque removal surgery. Further research in a bigger group of patients is still necessary to confirm our results.