Pericardial fluid exosome miRNA profiling

Pericardial sac surrounding the heart contains pericardial fluid (PF), which is rich in exosomes. PF exosomes increase angiogenesis in hypoxic endothelial cells and in animal model of hindlimb ischemia by passing the proangiogenic miRNAs to recipient cells. However, under pathological conditions such as diabetes, exosome cargo composition changes and harmful miRNAs can be transferred to the recipient cells and induce more deleterious effects in target tissues. In order to check cargo composition of different PF exosomes, we used PF exosomes from non-diabetic aortic valve replacement (AVR), mitral valve replacement (MVR), coronary artery bypass grafting (CABG) patients and CABG patients with diabetes. PF samples were collected from non-diabetic aortic valve replacement (AVR), mitral valve replacement (MVR), coronary artery bypass grafting (CABG) patients and CABG patients with diabetes (n=4 for each group) and exosomes were isolated from these samples using a commercially available kit. miRNA profiles of exosomes were determined using Exiqon human V4 microRNA PCR panel I+II.