β-Arrestin–Mediated Angiotensin II Type 1 Receptor Activation Promotes Pulmonary Vascular Remodeling in Pulmonary Hypertension
Zhiyuan Ma, Gayathri Viswanathan, Mason Sellig, Chanpreet Jassal, Issac Choi, Aditi Garikipati, Xinyu Xiong, Nour Nazo, Sudarshan Rajagopal
Abstract
Pulmonary arterial hypertension (PAH) is a disease of abnormal pulmonary vascular remodeling whose medical therapies are thought to primarily act as vasodilators but also may have effects on pulmonary vascular remodeling. The angiotensin II type 1 receptor (AT1R) is a G protein–coupled receptor that promotes vasoconstriction through heterotrimeric G proteins but also signals via β-arrestins, which promote cardioprotective effects and vasodilation through promoting cell survival. We found that an AT1R β-arrestin-biased agonist promoted vascular remodeling and worsened PAH, suggesting that the primary benefit of current PAH therapies is through pulmonary vascular reverse remodeling in addition to their vasodilation.