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Updated: Nov 5, 2025
Isolation and Culture of Pulmonary Endothelial Cells from Neonatal Mice
Published on: December 14, 2010
Angiopoietin-1 protects against endotoxin-induced neonatal lung injury and alveolar simplification in mice
Umar Salimi1, Heather L Menden2,3, Sherry M Mabry2,3
1Division of Pediatric Critical Care, Department of Pediatrics, Children's Mercy Kansas City, Kansas, MO, USA.
Background:
Sepsis in premature newborns is a risk factor for bronchopulmonary dysplasia (BPD), but underlying mechanisms of lung injury remain unclear. Aberrant expression of endothelial cell (EC) angiopoietin 2 (ANGPT2) disrupts angiopoietin 1 (ANGPT1)/TIE2-mediated endothelial quiescence, and is implicated in sepsis-induced acute respiratory distress syndrome in adults. We hypothesized that recombinant ANGPT1 will mitigate sepsis-induced ANGPT2 expression, inflammation, acute lung injury (ALI), and alveolar remodeling in the saccular lung.
Methods:
Effects of recombinant ANGPT1 on lipopolysaccharide (LPS)-induced endothelial inflammation were evaluated in human pulmonary microvascular endothelial cells (HPMEC). ALI and long-term alveolar remodeling were assessed in newborn mice exposed to intraperitoneal LPS and recombinant ANGPT1 pretreatment.
Results:
LPS dephosphorylated EC TIE2 in association with increased ANGPT2 in vivo and in vitro. ANGPT1 suppressed LPS and ANGPT2-induced EC inflammation in HPMEC. Neonatal mice treated with LPS had increased lung cytokine expression, neutrophilic influx, and cellular apoptosis. ANGPT1 pre-treatment suppressed LPS-induced lung Toll-like receptor signaling, inflammation, and ALI. LPS-induced acute increases in metalloproteinase 9 expression and elastic fiber breaks, as well as a long-term decrease in radial alveolar counts, were mitigated by ANGPT1.
Conclusions:
In an experimental model of sepsis-induced BPD, ANGPT1 preserved endothelial quiescence, inhibited ALI, and suppressed alveolar simplification.
Impact:
Key message: Angiopoietin 1 inhibits LPS-induced neonatal lung injury and alveolar remodeling. Additions to existing literature: Demonstrates dysregulation of angiopoietin-TIE2 axis is important for sepsis- induced acute lung injury and alveolar simplification in experimental BPD. Establishes recombinant Angiopoietin 1 as an anti-inflammatory therapy in BPD.
Impact:
Angiopoietin 1-based interventions may represent novel therapies for mitigating sepsis-induced lung injury and BPD in premature infants.
