title: IL-1 and TNF-α regulation of aryl hydrocarbon receptor (AhR) expression in HSY human salivary cells.
abstract: OBJECTIVE
  Recent findings demonstrate that nuclear receptor - aryl hydrocarbon receptor (AhR) may play an important role in the pathogenesis of Sjögren's syndrome (SS) via involvement in Epstein-Barr virus reactivation. In that study a reporter system was used. Therefore, it was decided to define AhR expression in human salivary cell line (HSY) and its functional regulators.
  
  
  METHODS
  The expression and functional regulation of AhR was studied in HSY cells. The cells were incubated with dioxin (TCDD) - AhR model inducer, IL-1 and TNF-α. qRT-PCR was applied to assess the expression of AHR, AHRR (AhR repressor), ARNT (AhR nuclear translocator) as well as AhR dependent genes: CYP1A1 and CYP1B1. Enzymatic activity of CYP1A1 and CYP1B1 was evaluated using luciferin-labelled CYPs substrate.
  
  
  RESULTS
  In general, dioxin did not significantly influence the expression of AHR and ARNT, but reduced AHRR level. AhR dependent gene expression, i.e. CYP1A1 and CYP1B1 increased gradually with TCDD incubation time. TNF-α significantly induced AHR along with CYP1A1 and CYP1B1 expression. IL-1β did not affect AHR expression, and had minimal effects on CYP1 mRNA levels. Exposure of HSY cells to TCDD resulted in time-dependent induction of CYP1A1 and CYP1B1 enzymatic activity.
  
  
  CONCLUSIONS
  This study documents functional expression of AhR in HSY as well as induction of AhR and its dependent genes by TNF-α.
authors.affiliation: Department of General Dentistry, Pomeranian Medical University, Powstancow Wlkp 72, 70-111, Szczecin, Poland. Electronic address: agdro@pum.edu.pl.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Drozdzik
authors.affiliation: Department of Chemistry and Biochemistry, Pomeranian Medical University, Powstancow Wlkp 72, 70-111, Szczecin, Poland.
authors.forename: Violetta
authors.initials: V
authors.lastname: Dziedziejko
authors.affiliation: Department of Pharmacology, Pomeranian Medical University, Powstancow Wlkp 72, 70-111, Szczecin, Poland.
authors.forename: Mateusz
authors.initials: M
authors.lastname: Kurzawski
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism; D002460:Cell Line; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D065633:Cytochrome P-450 CYP1B1; D004147:Dioxins / Q000494:pharmacology; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D000072317:Polychlorinated Dibenzodioxins / Q000493:pharmacokinetics; D018336:Receptors, Aryl Hydrocarbon / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012469:Salivary Glands / Q000166:cytology / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D004147:Dioxins; D007375:Interleukin-1; D000072317:Polychlorinated Dibenzodioxins; D018336:Receptors, Aryl Hydrocarbon; D014409:Tumor Necrosis Factor-alpha; D001189:Aryl Hydrocarbon Hydroxylases; C585496:CYP1B1 protein, human; D019363:Cytochrome P-450 CYP1A1; D065633:Cytochrome P-450 CYP1B1
keywords: AhR; HSY; IL-1; Salivary gland; TNF-α