title: Nrf2-Dependent and -Independent Effects oftert-Butylhydroquinone, CDDO-Im, and H2O2in Human Jurkat T Cells as Determined by CRISPR/Cas9 Gene Editing.
abstract: Nuclear factor erythroid 2-related factor 2 (Nrf2) is a stress-activated transcription factor activated by stimuli such as electrophilic compounds and other reactive xenobiotics. Previously, we have shown that the commonly used food additive and Nrf2 activatortert-butylhydroquinone (tBHQ) suppresses interleukin-2 (IL-2) production, CD25 expression, and NFκB activity in human Jurkat T cells. The purpose of the current studies was to determine whether these effects were dependent upon Nrf2 by developing a human Nrf2-null T cell model using clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 technology. The current studies show that suppression of CD25 expression by tBHQ is partially dependent on Nrf2, whereas inhibition of IL-2 secretion is largely Nrf2-independent. Interestingly, tBHQ inhibited NFκB activation in an Nrf2-independent manner. This was an unexpected finding since Nrf2 inhibits NFκB activation in other models. These results led us to investigate another more potent Nrf2 activator, the synthetic triterpenoid 1[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im). Treatment of wild-type and Nrf2-null Jurkat T cells with CDDO-Im resulted in an Nrf2-dependent suppression of IL-2. Furthermore, susceptibility to reactive oxygen species was significantly enhanced in the Nrf2-null clones as determined by decreased mitochondrial membrane potential and cell viability. Importantly, this study is the first to describe the generation of a human Nrf2-null model, which is likely to have multiple applications in immunology and cancer biology. Collectively, this study demonstrates a role for Nrf2 in the effects of CDDO-Im on CD25 and IL-2 expression, whereas the effect of tBHQ on these parameters is complex and likely involves modulation of multiple stress-activated transcription factors, including NFκB and Nrf2.
authors.affiliation: Department of Pharmacology and Toxicology (J.W.Z., T.P.M., K.T.L., C.E.R.), Institute for Integrated Toxicology (J.W.Z., C.E.R.), and Cell and Molecular Biology Program (J.W.Z. C.E.R.), Michigan State University, East Lansing, Michigan.
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Zagorski
authors.affiliation: Department of Pharmacology and Toxicology (J.W.Z., T.P.M., K.T.L., C.E.R.), Institute for Integrated Toxicology (J.W.Z., C.E.R.), and Cell and Molecular Biology Program (J.W.Z. C.E.R.), Michigan State University, East Lansing, Michigan.
authors.forename: Tyler P
authors.initials: TP
authors.lastname: Maser
authors.affiliation: Department of Pharmacology and Toxicology (J.W.Z., T.P.M., K.T.L., C.E.R.), Institute for Integrated Toxicology (J.W.Z., C.E.R.), and Cell and Molecular Biology Program (J.W.Z. C.E.R.), Michigan State University, East Lansing, Michigan.
authors.forename: Karen T
authors.initials: KT
authors.lastname: Liby
authors.affiliation: Department of Pharmacology and Toxicology (J.W.Z., T.P.M., K.T.L., C.E.R.), Institute for Integrated Toxicology (J.W.Z., C.E.R.), and Cell and Molecular Biology Program (J.W.Z. C.E.R.), Michigan State University, East Lansing, Michigan rockwelc@msu.edu.
authors.forename: Cheryl E
authors.initials: CE
authors.lastname: Rockwell
mesh_terms: D064112:Clustered Regularly Interspaced Short Palindromic Repeats / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D006873:Hydroquinones / Q000494:pharmacology*; D007093:Imidazoles / Q000494:pharmacology*; D007376:Interleukin-2 / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D008954:Models, Biological; D008956:Models, Chemical; D051267:NF-E2-Related Factor 2 / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D013268:Stimulation, Chemical
chemical_list: C472829:1-(2-cyano-3,12-dioxooleana-1,9-dien-28-oyl) imidazole; D004791:Enzyme Inhibitors; D006873:Hydroquinones; C508017:IL2RA protein, human; D007093:Imidazoles; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D051267:NF-E2-Related Factor 2; D016328:NF-kappa B; D009828:Oleanolic Acid; C018855:2-tert-butylhydroquinone