Nrf2 protects against airway disorders.
Nuclear factor-erythroid 2 related factor 2 (Nrf2) is a ubiquitous master transcription factor that regulates antioxidant response elements (AREs)-mediated expression of antioxidant enzyme and cytoprotective proteins. In the unstressed condition, Kelch-like ECH-associated protein 1 (Keap1) suppresses cellular Nrf2 in cytoplasm and drives its proteasomal degradation. Nrf2 can be activated by diverse stimuli including oxidants, pro-oxidants, antioxidants, and chemopreventive agents. Nrf2 induces cellular rescue pathways against oxidative injury, abnormal inflammatory and immune responses, apoptosis, and carcinogenesis. Application of Nrf2 germ-line mutant mice has identified an extensive range of protective roles for Nrf2 in experimental models of human disorders in the liver, gastrointestinal tract, airway, kidney, brain, circulation, and immune or nerve system. In the lung, lack of Nrf2 exacerbated toxicity caused by multiple oxidative insults including supplemental respiratory therapy (e.g., hyperoxia, mechanical ventilation), cigarette smoke, allergen, virus, bacterial endotoxin and other inflammatory agents (e.g., carrageenin), environmental pollution (e.g., particles), and a fibrotic agent bleomycin. Microarray analyses and bioinformatic studies elucidated functional AREs and Nrf2-directed genes that are critical components of signaling mechanisms in pulmonary protection by Nrf2. Association of loss of function with promoter polymorphisms in NRF2 or somatic and epigenetic mutations in KEAP1 and NRF2 has been found in cohorts of patients with acute lung injury/acute respiratory distress syndrome or lung cancer, which further supports the role for NRF2 in these lung diseases. In the current review, we address the role of Nrf2 in airways based on emerging evidence from experimental oxidative disease models and human studies.
Cho
Hye-Youn
HY
Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Building 101, MD D-201, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA. cho2@niehs.nih.gov
Kleeberger
Steven R
SR
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D000818:Animals; D001665:Binding Sites; D003598:Cytoskeletal Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D000072019:Kelch-Like ECH-Associated Protein 1; D008168:Lung / Q000378:metabolism*; D008171:Lung Diseases / Q000235:genetics / Q000378:metabolism / Q000517:prevention & control*; D051379:Mice; D018345:Mice, Knockout; D051267:NF-E2-Related Factor 2 / Q000235:genetics / Q000378:metabolism*; D018384:Oxidative Stress; D020218:Response Elements; D015398:Signal Transduction
D048868:Adaptor Proteins, Signal Transducing; D003598:Cytoskeletal Proteins; D047908:Intracellular Signaling Peptides and Proteins; C431364:KEAP1 protein, human; C117301:Keap1 protein, mouse; D000072019:Kelch-Like ECH-Associated Protein 1; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; C495636:Nfe2l2 protein, mouse