title: Nrf2-dependent and -independent responses to nitro-fatty acids in human endothelial cells: identification of heat shock response as the major pathway activated by nitro-oleic acid.
abstract: Electrophilic fatty acid derivatives, including nitrolinoleic acid and nitro-oleic acid (OA-NO(2)), can mediate anti-inflammatory and pro-survival signaling reactions. The transcription factor Nrf2, activated by electrophilic fatty acids, suppresses redox-sensitive pro-inflammatory gene expression and protects against vascular endothelial oxidative injury. It was therefore postulated that activation of Nrf2 by OA-NO(2) accounts in part for its anti-inflammatory actions, motivating the characterization of Nrf2-dependent and -independent effects of OA-NO(2) on gene expression using genome-wide transcriptional profiling. Control and Nrf2-small interfering RNA-transfected human endothelial cells were treated with vehicle, oleic acid, or OA-NO(2), and differential gene expression profiles were determined. Although OA-NO(2) significantly induced the expression of Nrf2-dependent genes, including heme oxygenase-1 and glutamate-cysteine ligase modifier subunit, the majority of OA-NO(2)-regulated genes were regulated by Nrf2-independent pathways. Moreover, gene set enrichment analysis revealed that the heat shock response is the major pathway activated by OA-NO(2), with robust induction of a number of heat shock genes regulated by the heat shock transcription factor. Inasmuch as the heat shock response mediates anti-inflammatory and cytoprotective actions, this mechanism is proposed to contribute to the protective cell signaling functions of nitro-fatty acids and other electrophilic fatty acid derivatives.
authors.affiliation: Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, University of Kuopio, FIN-70211 Kuopio, Finland.
authors.forename: Emilia
authors.initials: E
authors.lastname: Kansanen
authors.forename: Henna-Kaisa
authors.initials: HK
authors.lastname: Jyrkkänen
authors.forename: Oscar L
authors.initials: OL
authors.lastname: Volger
authors.forename: Hanna
authors.initials: H
authors.lastname: Leinonen
authors.forename: Annukka M
authors.initials: AM
authors.lastname: Kivelä
authors.forename: Sanna-Kaisa
authors.initials: SK
authors.lastname: Häkkinen
authors.forename: Steven R
authors.initials: SR
authors.lastname: Woodcock
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Schopfer
authors.forename: Anton J
authors.initials: AJ
authors.lastname: Horrevoets
authors.forename: Seppo
authors.initials: S
authors.lastname: Ylä-Herttuala
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Freeman
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Levonen
mesh_terms: D015153:Blotting, Western; D002460:Cell Line; D002478:Cells, Cultured; D016000:Cluster Analysis; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D020869:Gene Expression Profiling; D005721:Glutamate-Cysteine Ligase / Q000235:genetics / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism; D006358:Hot Temperature; D006801:Humans; D008041:Linoleic Acids / Q000494:pharmacology*; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000235:genetics / Q000378:metabolism; D051267:NF-E2-Related Factor 2 / Q000235:genetics* / Q000378:metabolism; D009574:Nitro Compounds / Q000494:pharmacology*; D009829:Oleic Acids / Q000494:pharmacology*; D020411:Oligonucleotide Array Sequence Analysis; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects
chemical_list: C501855:10-nitro-9,12-octadecadienoic acid; D008041:Linoleic Acids; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D009574:Nitro Compounds; D009829:Oleic Acids; C496541:HMOX1 protein, human; D051547:Heme Oxygenase-1; D016660:NAD(P)H Dehydrogenase (Quinone); C447479:NQO1 protein, human; C546365:GCLM protein, human; D005721:Glutamate-Cysteine Ligase