Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infections (LRTIs) in children worldwide. RSV infection rapidly generates reactive oxygen species (ROS) that produce oxidative DNA damage, with 8-oxoguanine (oxoG) being one of the most abundant. OxoG is repaired by the 8-oxoguanine DNA glycosylase1 (OGG1)-initiated DNA base excision repair pathway (BER). We have documented that ROS transiently inactivates OGG1 enzymatic activity, leading to formation of an OGG1-DNA complex in inducible gene promoters and in close proximity to NF?B-binding motifs. We have also demonstrated that: 1) OGG1- DNA complex at oxoG increases NF?B binding in vitro; and 2) OGG1 depletion or inhibition of OGG1 substrate binding by highly selective small molecules result in decrease NF?B-dependent gene expression in vivo. These data indicate that the OGG1-oxoG complex plays a key role in the innate immune response (IIR). As such, we recently found that OGG1 is required for RSV-induced expression of innate chemokines, cytokines, and interleukins constituting the IIR. Related to the overall theme of this P01, we have also shown that repeated activation of OGG1-dependent innate pathways resulted in modulation of gene networks controlling the actin cytoskeleton, extracellular matrix, cell adhesion, and cell junction apparatus, resulting in airway remodeling. Because of the high specificity of OGG1 for oxoG, these results point to a novel paradigm wherein oxoG functions as an epigenetic element that plays a central role in the regulation of genes that link IIR to airway remodeling. The overarching hypothesis of this project is that the RSV-induced oxidation of guanine to oxoG in gene regulatory regions is an epigenetic modification that links inflammation with airway remodeling via the NF?B pathway. This hypothesis will be tested in three Specific Aims: 1) RSV-induced pro-inflammatory gene expression and acute inflammation is dependent on ROS-induced oxidative damage to DNA and OGG1; 2) The OGG1 DNA complex atoxoG in the proximal promoter regions of IIR genes serves as a platform for NF?B binding occupancy in response to RSV infection; 3) The OGG1DNA complex links chronic oxidative stress with tissue remodeling in RSV-primed mice in response to allergen challenges. To achieve these aims, we will utilize mouse models, primary human small airway epithelial cells, nasopharyngeal cells isolated from RSV-infected infants, and well as state-of-the-art molecular technologies. Our studies contribute to the understanding of the role of the RSV-ROS-induced OGG1-DNA complex at oxoG in epigenetic regulation of NFkB-driven expression of IIR and airway remodeling genes in the context of RSV LRTI. This work will also advance innovative approaches for treatment of LRTI using available small-molecule inhibitors of OGG1.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program Projects (P01)
Project #
5P01AI062885-13
Application #
9974470
Study Section
Special Emphasis Panel (ZAI1)
Project Start
2004-09-01
Project End
2023-06-30
Budget Start
2020-07-01
Budget End
2021-06-30
Support Year
13
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of Texas Med Br Galveston
Department
Type
DUNS #
800771149
City
Galveston
State
TX
Country
United States
Zip Code
77555
Tian, Bing; Widen, Steven G; Yang, Jun et al. (2018) The NF?B subunit RELA is a master transcriptional regulator of the committed epithelial-mesenchymal transition in airway epithelial cells. J Biol Chem 293:16528-16545
Graber, Ted G; Rawls, Brandy L; Tian, Bing et al. (2018) Repetitive TLR3 activation in the lung induces skeletal muscle adaptations and cachexia. Exp Gerontol 106:88-100
Tian, Bing; Yang, Jun; Zhao, Yingxin et al. (2018) Central Role of the NF-?B Pathway in the Scgb1a1-Expressing Epithelium in Mediating Respiratory Syncytial Virus-Induced Airway Inflammation. J Virol 92:
Tian, Bing; Hosoki, Koa; Liu, Zhiqing et al. (2018) Mucosal bromodomain-containing protein 4 mediates aeroallergen-induced inflammation and remodeling. J Allergy Clin Immunol :
Wang, Ruoxi; Hao, Wenjing; Pan, Lang et al. (2018) The roles of base excision repair enzyme OGG1 in gene expression. Cell Mol Life Sci 75:3741-3750
Tian, Bing; Liu, Zhiqing; Yang, Jun et al. (2018) Selective Antagonists of the Bronchiolar Epithelial NF-?B-Bromodomain-Containing Protein 4 Pathway in Viral-Induced Airway Inflammation. Cell Rep 23:1138-1151
Ba, Xueqing; Boldogh, Istvan (2018) 8-Oxoguanine DNA glycosylase 1: Beyond repair of the oxidatively modified base lesions. Redox Biol 14:669-678
Visnes, Torkild; Cázares-Körner, Armando; Hao, Wenjing et al. (2018) Small-molecule inhibitor of OGG1 suppresses proinflammatory gene expression and inflammation. Science 362:834-839
Ochoa, Lorenzo F; Kholodnykh, Alexander; Villarreal, Paula et al. (2018) Imaging of Murine Whole Lung Fibrosis by Large Scale 3D Microscopy aided by Tissue Optical Clearing. Sci Rep 8:13348
Liu, Zhiqing; Tian, Bing; Chen, Haiying et al. (2018) Discovery of potent and selective BRD4 inhibitors capable of blocking TLR3-induced acute airway inflammation. Eur J Med Chem 151:450-461

Showing the most recent 10 out of 159 publications