title: Activation of the Nrf2 response by intrinsic hepatotoxic drugs correlates with suppression of NF-κB activation and sensitizes toward TNFα-induced cytotoxicity.
abstract: Drug-induced liver injury (DILI) is an important problem both in the clinic and in the development of new safer medicines. Two pivotal adaptation and survival responses to adverse drug reactions are oxidative stress and cytokine signaling based on the activation of the transcription factors Nrf2 and NF-κB, respectively. Here, we systematically investigated Nrf2 and NF-κB signaling upon DILI-related drug exposure. Transcriptomics analyses of 90 DILI compounds in primary human hepatocytes revealed that a strong Nrf2 activation is associated with a suppression of endogenous NF-κB activity. These responses were translated into quantitative high-content live-cell imaging of induction of a selective Nrf2 target, GFP-tagged Srxn1, and the altered nuclear translocation dynamics of a subunit of NF-κB, GFP-tagged p65, upon TNFR signaling induced by TNFα using HepG2 cells. Strong activation of GFP-Srxn1 expression by DILI compounds typically correlated with suppression of NF-κB nuclear translocation, yet reversely, activation of NF-κB by TNFα did not affect the Nrf2 response. DILI compounds that provided strong Nrf2 activation, including diclofenac, carbamazepine and ketoconazole, sensitized toward TNFα-mediated cytotoxicity. This was related to an adaptive primary protective response of Nrf2, since loss of Nrf2 enhanced this cytotoxic synergy with TNFα, while KEAP1 downregulation was cytoprotective. These data indicate that both Nrf2 and NF-κB signaling may be pivotal in the regulation of DILI. We propose that the NF-κB-inhibiting effects that coincide with a strong Nrf2 stress response likely sensitize liver cells to pro-apoptotic signaling cascades induced by intrinsic cytotoxic pro-inflammatory cytokines.
authors.affiliation: Division of Toxicology, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
authors.forename: Bram
authors.initials: B
authors.lastname: Herpers
authors.affiliation: Division of Toxicology, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
authors.forename: Steven
authors.initials: S
authors.lastname: Wink
authors.affiliation: Division of Toxicology, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
authors.forename: Lisa
authors.initials: L
authors.lastname: Fredriksson
authors.affiliation: Division of Toxicology, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
authors.forename: Zi
authors.initials: Z
authors.lastname: Di
authors.affiliation: Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Giel
authors.initials: G
authors.lastname: Hendriks
authors.affiliation: Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Harry
authors.initials: H
authors.lastname: Vrieling
authors.affiliation: Division of Toxicology, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
authors.forename: Hans
authors.initials: H
authors.lastname: de Bont
authors.affiliation: Division of Toxicology, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands. b.water@lacdr.leidenuniv.nl.
authors.forename: Bob
authors.initials: B
authors.lastname: van de Water
mesh_terms: D021581:Active Transport, Cell Nucleus; D056486:Chemical and Drug Induced Liver Injury / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D019295:Computational Biology; D030541:Databases, Genetic; D004305:Dose-Response Relationship, Drug; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D051267:NF-E2-Related Factor 2 / Q000235:genetics / Q000378:metabolism*; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000096:biosynthesis / Q000235:genetics; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D051996:Transcription Factor RelA / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000633:toxicity*
chemical_list: D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; C498143:RELA protein, human; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha; D049452:Green Fluorescent Proteins; D050862:Oxidoreductases Acting on Sulfur Group Donors; C504024:SRXN1 protein, human
keywords: Drug-induced liver injury; Live-cell imaging; NF-κB signaling; Nrf2 activation; Oxidative stress