Imbalance between vascular endothelial growth factor and endostatin levels in induced sputum from asthmatic subjects

Abstract

Background: Angiogenesis has recently attracted considerable attention as a component of airway remodeling in bronchial asthma. Vascular endothelial growth factor (VEGF) is highly expressed in asthmatic airways, and its contribution to airway remodeling has been reported. Although angiogenesis is regulated by a balance of angiogenic and antiangiogenic factors, the relative levels of antiangiogenic factors in asthmatic airways have not been evaluated. Objective: We sought to determine whether an imbalance between angiogenic and antiangiogenic factors exists in asthmatic airways. Methods: We simultaneously measured VEGF and endostatin levels and evaluated their correlation and balance in induced sputum from 18 steroid-naive asthmatic subjects and 11 healthy control subjects. After initial sputum induction, asthmatic subjects underwent 8 weeks of inhaled beclomethasone dipropionate (BDP; 800 μg/d) therapy, and sputum induction was then repeated. Results: VEGF and endostatin levels in induced sputum were significantly higher in asthmatic subjects than in control subjects (P