Bin Liu, Dan Yi, Shuai Li, Karina Ramirez, Xiaomei Xia, Yanhong Cao, Hanqiu Zhao, Ankit Tripathi, Shenfeng Qiu, Mrinalini Kala, Ruslan Rafikov, Haiwei Gu, Vinicio de jesus Perez, Sarah-Eve Lemay, Christopher C. Glembotski, Kenneth S. Knox, Sebastien Bonnet, Vladimir V. Kalinichenko, You-Yang Zhao, Michael B. Fallon, Olivier Boucherat, Zhiyu Dai
College of Medicine-Phoenix and University of Arizona. Washington University School of Medicine in St. Louis. Guangzhou Medical University. Indiana University College of Medicine. Arizona State University. Stanford University. Laval University. Phoenix Children’s Hospital. Ann & Robert H. Lurie Children’s Hospital of Chicago and Northwestern University Feinberg School of Medicine.
United States, China and Canada
Arteriosclerosis, Thrombosis and Vascular Biology
Arterioscler Thromb Vasc Biol 2025;
DOI: 10.1161/ATVBAHA.124.321173
Abstract
Background: Pulmonary arterial hypertension (PAH) is a devastating disease characterized by obliterative vascular remodeling and persistent increase of vascular resistance, leading to right heart failure and premature death. Understanding the cellular and molecular mechanisms will help develop novel therapeutic approaches for patients with PAH. Recent studies showed that FABP (fatty acid-binding protein) 4 and FABP5 are expressed in endothelial cells (ECs) across multiple tissues, and circulating FABP4 level is elevated in patients with PAH. However, the role of endothelial FABP4/5 in the pathogenesis of PAH remains undetermined.
Methods: FABP4/5 expression was examined in pulmonary arterial ECs and lung tissues from patients with idiopathic PAH and pulmonary hypertension (PH) rat models. Plasma proteome analysis was performed in human PAH samples. Echocardiography, hemodynamics, histology, and immunostaining were performed to evaluate the lung and heart PH phenotypes in Egln1Tie2Cre (CKO) mice and Egln1Tie2Cre/Fabp4/5-/- (TKO) mice. Bulk RNA sequencing (RNA-seq), single-cell RNA sequencing analysis, and spatial transcriptomic analysis were performed to understand the cellular and molecular mechanisms of endothelial FABP4/5-mediated PAH pathogenesis.
Results: Both FABP4 and FABP5 were highly induced in ECs of CKO mice and pulmonary arterial ECs from patients with idiopathic PAH (IPAH) and in whole lungs of PH rats. Plasma levels of FABP4/5 were upregulated in patients with IPAH and directly correlated with severity of hemodynamics and biochemical parameters. Genetic deletion of both Fabp4 and Fabp5 in CKO mice caused a reduction of right ventricular systolic pressure and right ventricular hypertrophy, attenuated pulmonary vascular remodeling, and prevented the right heart failure secondary to PH. FABP4/5 deletion also normalized EC glycolysis and distal arterial programming, reduced reactive oxygen species and HIF (hypoxia-inducible factor)-2α expression, and decreased aberrant EC proliferation in CKO lungs.
Conclusions: PH causes aberrant expression of FABP4/5 in pulmonary ECs, which leads to enhanced EC glycolysis and distal arterial programming, contributing to the accumulation of arterial ECs and vascular remodeling and exacerbating the disease.
Category
Class I. Idiopathic Pulmonary Hypertension
Vascular Cell Biology and Mechanisms of Pulmonary Vascular Disease
Animal Models of Pulmonary Vascular Disease and Therapy
Genetic Factors Associated with Pulmonary Vascular Disease
Pulmonary Vascular Pathology
Age Focus: No Age-Related Focus
Fresh or Filed Publication: Fresh (PHresh). Less than 1-2 years since publication
Article Access
Free PDF File or Full Text Article Available Through PubMed or DOI: Yes