Serum levels of angiopoietin-2 and vascular endothelial growth factor in severe refractory asthma

Abstract Background Airway and vascular remodeling may play a prominent role in the clinical severity of severe refractory asthma (SRA). Angiopoietin-1 (Ang-1) is an essential mediator of angiogenesis by establishing vascular integrity, whereas angiopoietin-2 (Ang-2) acts as its natural inhibitor. Vascular endothelial growth factor (VEGF) is considered to be the most important angiogenetic factor, which induces vascular endothelial cell proliferation, tubule formation and increases microvascular permeability. Objective In the present study, we aimed to determine the serum levels of angiopoietin-2 and VEGF in patients with SRA as both are involved in remodeling and angiogenesis occurring in SRA leading to resistance to inhaled steroid. Methods Twenty five patients with SRA, 25 patients with moderate asthma, and 20 healthy subjects are included in this study. Serum Angiopoietin-2 and vascular endothelial growth factor were estimated in all groups. Results Ang-2 (pg/ml) levels were significantly higher among patients with SRA compared to patients with moderate asthma and healthy control. Vascular endothelial growth factor was significantly higher in patients with SRA compared with the other two groups. Conclusion Results provide suggestion for possible mechanisms involving angiopoietin-2 and VEGF in the pathogenesis of SRA.