SERPINE1 and Headache: Some new potential risk factors for atherosclerosis and platelet aggregation (i.e., brain-derived neurotrophic factor (BDNF), sCD40L (soluble CD40 ligand), serpin E1/PAI I (endothelial plasminogen activator inhibitor) and vascular endothelial growth factor (VEGF)) were earlier correlated with headaches [21,69,70,71,72,73,74,75,76,77].