Anti-Angiogenic Vascular Endothelial Growth Factor-A Isoform: VEGF-A165b is Present in Human Right Atrial Appendage, but is not Altered in Diabetes

Abstract

Introduction: The alternative splice variant of vascular endothelial growth factor (VEGF-A): VEGF-A165b is anti-angiogenic and has been described to regulate angiogenesis in cancer, retinopathy, and obesity. In this study, we describe for the first time, presence of VEGF-A165b in human cardiac tissue, and sought to determine whether VEGF-A165b is altered in patients with diabetes. Methods and Results: A total of 33 right atrial appendage biopsies were collected from consenting patients during cardiac or vascular surgery at the John Hunter Hospital. Patient demographics and co-morbidities were recorded on the day of surgery and confirmed via access to medical records. A majority of patients (82%) were male; 32% of patients had previous MI, n = 10 (30%) patients had diabetes. Detection of VEGF-A165b levels were determined using the ELISA kit (R&D systems). Patients with diabetes tended to have lower VEGF-A165b expression (p = 0.1). There was no difference in VEGF-A165b expressions in patients with previous myocardial infarction or diastolic impairment. On multivariate analysis, presence of diabetes is not associated with changes in VEGF-A165b expression, independent of age, BMI, gender, and cardiovascular co-morbidities. Conclusions: VEGF-A165b is present in human cardiac tissue. In patients who underwent CABG surgery, there was no difference in VEGFA-165b expression between patients with vs without diabetes. Larger study population is required to dissect the regulatory mechanisms of cardiac VEGF-A165b in metabolically-induced cardiovascular pathologies.