Abstract 15825: Acetylation and Methylation Modifiers Attenuate Thrombin-induced eNOS/RhoA Signaling and Restore Adherens Junction Integrity in Acute Lung Injury
Introduction: Acute lung injury (ALI) involves severe dysregulation of the restrictive endothelial barrier with consequent fluid exudation and cellular infiltration. Targeting pathways that may restore lung microvascular endothelial barrier function may lead to new therapy for this condition.
Hypothesis: Epigenetic modifiers TSA (Trichostatin-A, HDAC inhibitor) and Aza (5-aza-2-deoxycytidine, DNA methyl transferase inhibitor) when used together will inhibit thrombin-induced eNOS/RhoA signaling, restore adherens junction (AJ) integrity, and diminish endothelial hyperpermeability.
Methods: Molecular signaling, AJ integrity, and endothelial permeability were assessed by quantitative RT-PCR, immunofluorescence, Western analysis, and trans-endothelial resistance (TER).
Results: Our data show that the combination of TSA+Aza is more effective in inhibiting thrombin-induced lung hyperpermeability than TSA alone or Aza alone. We used an in vitro culture system of TER to determine the effects of TSA+Aza on thrombin-induced change in resistance over human pulmonary arterial endothelial cells. Our immunofluorescence data show that treatment with TSA+Aza ameliorates thrombin-induced endothelial barrier disruption (Figure, white arrows). The Western data show that treatment with TSA+Aza decreases the levels of thrombin-induced RhoA and eNOS signaling in lung endothelial cells.
Conclusions: These data indicate, for the first time, that the combination of TSA+Aza exerts a protective role in preventing lung microvascular hyperpermeability and endothelial barrier disruption in thrombin-induced lung injury. This combination has therapeutic potential for acute lung injury.
Author Disclosures: J. Thangavel: None. S. Rajasingh: None. B. Barani: None. B. Dawn: None. J. Rajasingh: None.
This research has received full or partial funding support from the American Heart Association
- © 2014 by American Heart Association, Inc.