There is a strong association between fibrotic lung disease and oxidative stress. Recent studies from our laboratory implicate the reactive oxygen species-generating enzyme, NADPH oxidase-4 (N0X4) in lung fibrosis. N0X4 mediates myofibroblast differentiation, matrix synthesis, and contractility;siRNA targeting of NOX4 abrogates fibrosis in animal models of non-infectious lung injury. Other reported studies of systemic N0X4 deficiency in mice further support the concept that N0X4 is critical for in-vivo fibrogenesis;however, the mechanisms and potential cell-specific effects of N0X4 remain unclear. N0X4 is expressed in fibrotic regions of alveolar and vascular remodeling in idiopathic pulmonary fibrosis (IPF). Our preliminary data demonstrate that N0X4 expression is upregulated in lung fibroblasts (Fbs) isolated from IPF patients; N0X4 expression is induced in pleural mesothelial cells (PMCs) during the process of a mesothelial-to-mesenchymal transition (Project 1) and is regulated by matrix stiffness;miR-31 regulates integrin a5 and RhoA (Project 2), which regulates cellular contractility and reciprocally controls matrix stiffness. Exogenous N0X4 expression activates latent TGF-P, and N0X4-dependent reactive oxygen species (ROS) mediates matrix cross linking in the presence of heme peroxidases. The central hypothesis of this project is that N0X4 mediates myofibroblast differentiation and contractility in IPF, and that targeting of NOX by RNAi approaches or small molecule inhibitors protects against fibrosis in animal models.
Our specific aims are to (1) determine whether lung expression of N0X4 is predictive of disease severity and/or progression in IPF;(2) determine mechanisms of N0X4-dependent H2O2 generation in activation of latent TGF-(3 and in oxidative matrix cross linking that reciprocally contributes to matrix stiffness;(3) determine whether conditional deletion of N0X4 in Fbs and/or PMCs protects against fibrosis in experimental models of lung fibrosis;and (4) determine the efficacy of targeting N0X4 with small molecule inhibitors and/or siRNA in experimental models of lung fibrosis. These studies will inform and support a potential role of N0X4 as a novel therapeutic target in IPF.

Public Health Relevance

This project seeks to identify effective drug therapies for IPF. Specifically, we aim to identify an anti-oxidant therapeutic approach that will be more specific and effective than those in completed or ongoing clinical trials in IPF.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Program Projects (P01)
Project #
Application #
Study Section
Special Emphasis Panel (ZHL1)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Alabama Birmingham
United States
Zip Code
Pennathur, Subramaniam; Vivekanandan-Giri, Anuradha; Locy, Morgan L et al. (2016) Oxidative Modifications of Protein Tyrosyl Residues Are Increased in Plasma of Human Subjects with Interstitial Lung Disease. Am J Respir Crit Care Med 193:861-8
Liu, Rui-Ming; Eldridge, Stephanie; Watanabe, Nobuo et al. (2016) Therapeutic potential of an orally effective small molecule inhibitor of plasminogen activator inhibitor for asthma. Am J Physiol Lung Cell Mol Physiol 310:L328-36
Larson-Casey, Jennifer L; Deshane, Jessy S; Ryan, Alan J et al. (2016) Macrophage Akt1 Kinase-Mediated Mitophagy Modulates Apoptosis Resistance and Pulmonary Fibrosis. Immunity 44:582-96
Kurundkar, Ashish; Thannickal, Victor J (2016) Redox mechanisms in age-related lung fibrosis. Redox Biol 9:67-76
Kulkarni, Tejaswini; Willoughby, John; Acosta Lara, Maria Del Pilar et al. (2016) A bundled care approach to patients with idiopathic pulmonary fibrosis improves transplant-free survival. Respir Med 115:33-8
Rangarajan, Sunad; Kurundkar, Ashish; Kurundkar, Deepali et al. (2016) Novel Mechanisms for the Antifibrotic Action of Nintedanib. Am J Respir Cell Mol Biol 54:51-9
Rangarajan, Sunad; Locy, Morgan L; Luckhardt, Tracy R et al. (2016) Targeted Therapy for Idiopathic Pulmonary Fibrosis: Where To Now? Drugs 76:291-300
Kulkarni, Tejaswini; de Andrade, Joao; Zhou, Yong et al. (2016) Alveolar epithelial disintegrity in pulmonary fibrosis. Am J Physiol Lung Cell Mol Physiol 311:L185-91
Cui, Huachun; Banerjee, Sami; Xie, Na et al. (2016) MicroRNA-27a-3p Is a Negative Regulator of Lung Fibrosis by Targeting Myofibroblast Differentiation. Am J Respir Cell Mol Biol 54:843-52
Swamy, Shobha M; Rajasekaran, Namakkal S; Thannickal, Victor J (2016) Nuclear Factor-Erythroid-2-Related Factor 2 in Aging and Lung Fibrosis. Am J Pathol 186:1712-23

Showing the most recent 10 out of 51 publications