title: Vitamin D derivatives: calcitriol and tacalcitol inhibits interleukin-6 and interleukin-8 expression in human nasal polyp fibroblast cultures.
abstract: OBJECTIVE
  Biologically active vitamin D3 (VD) derivatives possess modulatory activities on immunological and inflammatory responses which can be reflected by altered levels of pro-inflammatory chemokines. Nasal polyposis (NP), defined as a chronic inflammatory process of upper respiratory system, could be influenced by VD derivatives. The purpose of this study was to investigate the influence of 1alpha,25-dihydroxyvitamin D3 (calcitriol) and 1alpha,24(R)-dihydroxyvitamin D3 (tacalcitol) on the secretion of IL-6 and IL-8 by fibroblasts derived from NP.
  
  
  METHODS
  The study involved 12 fibroblast cultures derived from NP samples obtained from surgically treated patients. Measurements were performed on the polyp cells after the 6-9 passages. Culture stimulation involved treatment with tacalcitol and calcitriol at a defined strength (from 10(-7)M to 10(-4)M). IL-6 and IL-8 concentrations were estimated with ELISA.
  
  
  RESULTS
  Treatment with calcitriol or tacalcitol inhibits the synthesis of both IL-6 and IL-8 compared to the control group. The dose dependence of this effect has been confirmed. VD derivatives influence was marked at higher concentrations. Significant interleukin decrease was observed at 10(-5) and 10(-4) for calcitriol and 10-4 in the case of tacalcitol.
  
  
  CONCLUSIONS
  The present study demonstrates that calcitriol and tacalcitol are capable of affecting pro-inflammatory cytokine (IL-6 and IL-8) levels in NP cultures. Our data imply a potential therapeutical application of topical VD derivates in NP and warrant further investigation.
authors.affiliation: Department of Otolaryngology, Wroclaw Medical University, Wroclaw, Poland. beatanm@wp.pl
authors.forename: B
authors.initials: B
authors.lastname: Rostkowska-Nadolska
authors.forename: E
authors.initials: E
authors.lastname: Sliupkas-Dyrda
authors.forename: J
authors.initials: J
authors.lastname: Potyka
authors.forename: D
authors.initials: D
authors.lastname: Kusmierz
authors.forename: M
authors.initials: M
authors.lastname: Fraczek
authors.forename: T
authors.initials: T
authors.lastname: Krecicki
authors.forename: P
authors.initials: P
authors.lastname: Kubik
authors.forename: M
authors.initials: M
authors.lastname: Zatonski
authors.forename: M
authors.initials: M
authors.lastname: Latocha
mesh_terms: D002117:Calcitriol / Q000494:pharmacology*; D002478:Cells, Cultured; D004100:Dihydroxycholecalciferols / Q000494:pharmacology*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D016209:Interleukin-8 / Q000378:metabolism*; D009298:Nasal Polyps / Q000473:pathology*; D014807:Vitamin D / Q000031:analogs & derivatives / Q000494:pharmacology*
chemical_list: D004100:Dihydroxycholecalciferols; D015850:Interleukin-6; D016209:Interleukin-8; D014807:Vitamin D; C023850:1 alpha,24-dihydroxyvitamin D3; D002117:Calcitriol