title: Effect of globular adiponectin on interleukin-6 and interleukin-8 expression in periodontal ligament and gingival fibroblasts.
abstract: OBJECTIVE
  Globular adiponectin (gAd) is a type of adipocytokine, which is mainly produced by adipose tissue. It has been reported that gAd acts as a pro- as well as an anti-inflammatory factor. Interleukin (IL)-6 and IL-8 are pro-inflammatory cytokines. To investigate the role of gAd on periodontal tissues, the expression of adiponectin receptor 1 (AdipoR1) and the effect of gAd on the expression of IL-6 and IL-8 were investigated in periodontal ligament (PDL) and gingival fibroblasts.
  
  
  METHODS
  PDL and gingival fibroblasts were cultured from human periodontal tissues. gAd derived from Escherichia coli and murine myeloma cells were used. The expression of AdipoR1 was estimated by reverse transcription-polymerase chain reaction and western blot. The expression of cytokines was measured by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  PDL and gingival fibroblasts expressed both mRNA and protein of AdipoR1. gAd derived from E. coli increased the production of IL-6 and IL-8, but polymyxin B, an inhibitor of lipopolysaccharide (LPS), inhibited IL-6 and IL-8 production induced by gAd in both types of cells. gAd derived from murine myeloma cells did not induce IL-6 and IL-8 production in those cells. gAd derived from E. coli contained higher levels of LPS than gAd derived from murine myeloma cells. LPS increased production of IL-6 and IL-8 in PDL and gingival fibroblasts, but pretreatment of cells with gAd derived from murine myeloma cells did not inhibit LPS-induced IL-6 and IL-8 expression.
  
  
  CONCLUSIONS
  Our results suggest that PDL and gingival fibroblasts express AdipoR1 and that gAd does not act as a modulator of IL-6 and IL-8 expression in PDL and gingival fibroblasts.
authors.affiliation: Department of Oral Biology, BK21 Project, Oral Science Research Center, Yonsei University College of Dentistry, Seoul, Korea.
authors.forename: Hong Gyu
authors.initials: HG
authors.lastname: Park
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Bak
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Kim
authors.forename: Yang-Sin
authors.initials: YS
authors.lastname: Lee
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Jeong-Heon
authors.initials: JH
authors.lastname: Cha
authors.forename: Yun-Jung
authors.initials: YJ
authors.lastname: Yoo