There are only a few therapeutic approaches, and most of them were made with apelin-13, which improved vascular remodeling in mice exposed to chronic hypoxia (Fan et al., 2020) [pyr1]-Apelin-13 infusion decreased PVR and increased cardiac output in an acute study of 19 PAH patients (Brash et al., 2018). Here, APLN is linked to pulmonary arterial hypertension.