title: RNA sequencing reveals distinct mechanisms underlying BET inhibitor JQ1-mediated modulation of the LPS-induced activation of BV-2 microglial cells.
abstract: BACKGROUND
  Microglial cells become rapidly activated through interaction with pathogens, and their persistent activation is associated with the production and secretion of various pro-inflammatory genes, cytokines, and chemokines, which may initiate or amplify neurodegenerative diseases. Bromodomain and extraterminal domain (BET) proteins are a group of epigenetic regulators that associate with acetylated histones and facilitate the transcription of target genes. A novel synthetic BET inhibitor, JQ1, was proven to exert immunosuppressive activities by inhibiting the expression of IL-6 and Tnf-α in macrophages. However, a genome-wide search for JQ1 molecular targets is largely unexplored in microglia.
  
  
  METHODS
  The present study was aimed at evaluating the anti-inflammatory function and underlying genes targeted by JQ1 in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells using two transcriptomic techniques: global transcriptomic biological duplicate RNA sequencing and quantitative real-time PCR. Associated biological pathways and functional gene ontology were also evaluated.
  
  
  RESULTS
  With a cutoff value of P ≤ 0.01 and fold change ≥1.5 log2, the expression level of 214 and 301 genes, including pro-inflammatory cytokine, chemokine, and transcription factors, was found to be upregulated in BV-2 cells stimulated with LPS for 2 and 4 h, respectively. Among these annotated genes, we found that JQ1 selectively reduced the expression of 78 and 118 genes (P ≤ 0.01, and fold change ≥ 1.5, respectively). Importantly, these inflammatory genes were not affected by JQ1 treatment alone. Furthermore, we confirmed that JQ1 reduced the expression of key inflammation- and immunity-related genes as well as cytokines/chemokines in the supernatants of LPS-treated primary microglial cells isolated from 3-day-old ICR mice. Utilizing functional group analysis, the genes affected by JQ1 were classified into four categories related to biological regulation, immune system processes, and response to stimuli. Moreover, the biological pathways and functional genomics obtained in this study may facilitate the suppression of different key inflammatory genes through JQ1-treated BV-2 microglial cells.
  
  
  CONCLUSIONS
  These unprecedented results suggest the BET inhibitor JQ1 as a candidate for the prevention or therapeutic treatment of inflammation-mediated neurodegenerative diseases.
authors.affiliation: Department of Molecular and Life Science, Hanyang University, 1271 Sa 3-dong, Ansan, Gyeonggi-do, 426-791, South Korea. khjung2@gmail.com.
authors.forename: Kyoung Hwa
authors.initials: KH
authors.lastname: Jung
authors.affiliation: Department of Bionanotechnology, Hanyang University, 222 Wangsimni-ro, Seoul, 133-791, South Korea. amitabhdas.kn@gmail.com.
authors.forename: Amitabh
authors.initials: A
authors.lastname: Das
authors.affiliation: Department of Molecular and Life Science, Hanyang University, 1271 Sa 3-dong, Ansan, Gyeonggi-do, 426-791, South Korea. jincchai@gmail.com.
authors.forename: Jin Choul
authors.initials: JC
authors.lastname: Chai
authors.affiliation: Department of Molecular and Life Science, Hanyang University, 1271 Sa 3-dong, Ansan, Gyeonggi-do, 426-791, South Korea. eio3492@gmail.com.
authors.forename: Sun Hwa
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Molecular and Life Science, Hanyang University, 1271 Sa 3-dong, Ansan, Gyeonggi-do, 426-791, South Korea. nscdri@gmail.com.
authors.forename: Nishi
authors.initials: N
authors.lastname: Morya
authors.affiliation: Department of Molecular and Life Science, Hanyang University, 1271 Sa 3-dong, Ansan, Gyeonggi-do, 426-791, South Korea. kspark73@gmail.com.
authors.forename: Kyoung Sun
authors.initials: KS
authors.lastname: Park
authors.affiliation: Department of Molecular and Life Science, Hanyang University, 1271 Sa 3-dong, Ansan, Gyeonggi-do, 426-791, South Korea. yslee@hanyang.ac.kr.
authors.forename: Young Seek
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Department of Molecular and Life Science, Hanyang University, 1271 Sa 3-dong, Ansan, Gyeonggi-do, 426-791, South Korea. ygchai@hanyang.ac.kr.|Department of Bionanotechnology, Hanyang University, 222 Wangsimni-ro, Seoul, 133-791, South Korea. ygchai@hanyang.ac.kr.
authors.forename: Young Gyu
authors.initials: YG
authors.lastname: Chai
mesh_terms: D000818:Animals; D001381:Azepines / Q000494:pharmacology*; D001483:Base Sequence; D002461:Cell Line, Transformed; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D017628:Microglia / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism; D014230:Triazoles / Q000494:pharmacology*
chemical_list: C561695:(+)-JQ1 compound; D001381:Azepines; D016207:Cytokines; D007166:Immunosuppressive Agents; D008070:Lipopolysaccharides; D014157:Transcription Factors; D014230:Triazoles