Interleukin-6 in pulmonary artery hypertension

Abstract

Interleukin (IL)-6 is a pleiotropic cytokine, playing an important role in various pathological conditions, such as inflammatory, infectious, and neoplastic disorders. The casual relationship between IL-6 levels and development of pulmonary artery hypertension (PAH) has been elusive. Based on comprehensive retrieval of pertinent literature of recent two decades, this article aims to give an overview of the impact of IL-6 on PAH development in view of both clinical and experimental aspects. Results showed that IL-6 was overexpressed in all types of PAH in both human and animal models. The elevated IL-6 levels were closely related to right ventricular (RV) dysfunction and predicted poor prognosis and mortality of PAH patients. Several IL-6-regulated signaling pathways including transforming growth factor (TGF)-β/bone morphogenetic protein signaling pathway are involved in PAH development. IL-6 antagonizing agents are effective in ameliorating the symptoms and improving the RV function of PAH patients.