Faculty Collaboration Database

Decreased endothelial nitric oxide synthase expression and function contribute to impaired mitochondrial biogenesis and oxidative stress in fetal lambs with persistent pulmonary hypertension. Am J Physiol Lung Cell Mol Physiol 2016 Jan 01;310(1):L40-9

Date

11/01/2015

Pubmed ID

26519208

Pubmed Central ID

PMC4698434

DOI

10.1152/ajplung.00392.2014

Scopus ID

2-s2.0-84953297007 (requires institutional sign-in at Scopus site)   59 Citations

Abstract

Impaired vasodilation in persistent pulmonary hypertension of the newborn (PPHN) is characterized by mitochondrial dysfunction. We investigated the hypothesis that a decreased endothelial nitric oxide synthase level leads to impaired mitochondrial biogenesis and function in a lamb model of PPHN induced by prenatal ductus arteriosus constriction. We ventilated PPHN lambs with 100% O2 alone or with inhaled nitric oxide (iNO). We treated pulmonary artery endothelial cells (PAECs) from normal and PPHN lambs with detaNONOate, an NO donor. We observed decreased mitochondrial (mt) DNA copy number, electron transport chain (ETC) complex subunit levels, and ATP levels in PAECs and lung tissue of PPHN fetal lambs at baseline compared with gestation matched controls. Phosphorylation of AMP-activated kinase (AMPK) and levels of peroxisome proliferator-activated receptor-γ coactivator 1-α (PGC-1α) and sirtuin-1, which facilitate mitochondrial biogenesis, were decreased in PPHN. Ventilation with 100% O2 was associated with larger decreases in ETC subunits in the lungs of PPHN lambs compared with unventilated PPHN lambs. iNO administration, which facilitated weaning of FiO2 , partly restored mtDNA copy number, ETC subunit levels, and ATP levels. DetaNONOate increased eNOS phosphorylation and its interaction with heat shock protein 90 (HSP90); increased levels of superoxide dismutase 2 (SOD2) mRNA, protein, and activity; and decreased the mitochondrial superoxide levels in PPHN-PAECs. Knockdown of eNOS decreased ETC protein levels in control PAECs. We conclude that ventilation with 100% O2 amplifies oxidative stress and mitochondrial dysfunction in PPHN, which are partly improved by iNO and weaning of oxygen.

Author List

Afolayan AJ, Eis A, Alexander M, Michalkiewicz T, Teng RJ, Lakshminrusimha S, Konduri GG

Authors

Adeleye James Afolayan MD Associate Professor in the Pediatrics department at Medical College of Wisconsin
Girija Ganesh Konduri MD Chief, Professor in the Pediatrics department at Medical College of Wisconsin
Ru-Jeng Teng MD Professor in the Pediatrics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Animals, Newborn
Endothelial Cells
Female
Fetus
Hypertension, Pulmonary
Mitochondria
Nitric Oxide
Nitric Oxide Synthase Type III
Oxidative Stress
Peroxisome Proliferator-Activated Receptors
Persistent Fetal Circulation Syndrome
Pregnancy
Sheep