Transpulmonary generation of cell-free hemoglobin contributes to vascular dysfunction in pulmonary arterial hypertension via dysregulated clearance mechanisms.

ABSTRACT: Circulating cell-free hemoglobin (CFH) is elevated in pulmonary arterial hypertension (PAH) and associated with poor outcomes but the mechanisms are unknown. We hypothesized that CFH is generated from the pulmonary circulation and inadequately cleared in PAH. Transpulmonary CFH (difference between wedge and pulmonary artery positions) and lung hemoglobin α were analyzed in patients with PAH and healthy controls. Haptoglobin genotype and plasma hemoglobin processing proteins were analyzed in patients with PAH, unaffected bone morphogenetic protein receptor type II mutation carriers (UMCs), and control subjects. Transpulmonary CFH was increased in patients with PAH (p = 0.04) and correlated with pulmonary vascular resistanc (PVR) (r _s = 0.75, p = 0.02) and mea

SUBMITTER: Meegan JE 

PROVIDER: S-EPMC9841468 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature