EDN1 and pulmonary arterial hypertension: In a study of pulmonary hypertension using a heart failure with reduced ejection fraction (HFrEF) model, a first-in-class anti-fibrotic, anti-inflammatory, and anti-proliferative compound PBI-4050 reduced activation of lung fibroblasts by IL6, TGFβ, and ET-1, all three factors found to be upregulated in our study, resulting in reduced lung fibrosis and remodeling64.