title: Activation of the Nrf2-ARE pathway by siRNA knockdown of Keap1 reduces oxidative stress and provides partial protection from MPTP-mediated neurotoxicity.
abstract: Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that binds to the antioxidant response element, a cis-acting regulatory element that increases expression of detoxifying enzymes and antioxidant proteins. Kelch-like ECH associating protein 1 (Keap1) protein is a negative regulator of Nrf2. Previous work has shown that genetic overexpression of Nrf2 is protective in vitro and in vivo. To modulate the Nrf2-ARE system without overexpressing Nrf2, we used short interfering RNA (siRNA) directed against Keap1. Keap1 siRNA administration in primary astrocytes increased the levels of Nrf2-ARE driven genes and protected against oxidative stress. Moreover, Keap1 siRNA resulted in a persistent upregulation of the Nrf2-ARE pathway and protection against oxidative stress in primary astrocytes. Keap1 siRNA injected into the striatum was also modestly protective against MPTP-induced dopaminergic terminal damage. These data indicate that activation of endogenous intracellular levels of Nrf2 is sufficient to protect in models of oxidative stress and Parkinson's disease.
authors.affiliation: Division of Pharmaceutical Sciences, University of Wisconsin, Madison, WI, USA.
authors.forename: Tracy P
authors.initials: TP
authors.lastname: Williamson
authors.forename: Delinda A
authors.initials: DA
authors.lastname: Johnson
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Johnson
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism; D000975:Antioxidants / Q000378:metabolism*; D001253:Astrocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D001665:Binding Sites; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D019610:Cytoprotection; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D059290:Dopaminergic Neurons / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D015316:Genetic Therapy / Q000379:methods*; D000072019:Kelch-Like ECH-Associated Protein 1; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism; D020267:MPTP Poisoning / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D051379:Mice; D008822:Mice, Transgenic; D051267:NF-E2-Related Factor 2 / Q000378:metabolism*; D016877:Oxidants / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects*; D000073718:Pancreatitis-Associated Proteins; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism*; D020218:Response Elements; D013997:Time Factors; D014162:Transfection; D020122:tert-Butylhydroperoxide / Q000633:toxicity
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000951:Antigens, Neoplasm; D000975:Antioxidants; D014408:Biomarkers, Tumor; D003598:Cytoskeletal Proteins; C117301:Keap1 protein, mouse; D000072019:Kelch-Like ECH-Associated Protein 1; D037181:Lectins, C-Type; D051267:NF-E2-Related Factor 2; C495636:Nfe2l2 protein, mouse; D016877:Oxidants; D000073718:Pancreatitis-Associated Proteins; D034741:RNA, Small Interfering; D020122:tert-Butylhydroperoxide