title: miRNA-146 negatively regulates the production of pro-inflammatory cytokines via NF-κB signalling in human gingival fibroblasts.
abstract: OBJECTIVE
  In human gingival fibroblasts (HGFs), TLR4 recognises Pathogen-associated molecular patterns (PAMPs), such as LPS, and subsequently activates downstream signals that lead to the production of pro-inflammatory cytokines. The aim of this study was to explore the mechanisms of LPS-induced miRNA-146 regulation of TLR4 signals in HGFs.
  
  
  METHODS
  HGFs were treated with Porphyromonas gingivalis (P.g) LPS, the cells were harvested, and kinase phosphorylation levels were detected by western blot. Selective pharmacological inhibitors and agonists were used to block or activate the relevant kinases, miRNA-146a/b expression levels were detected by real-time PCR, and IL-1, IL-6, and TNF-α production were measured by enzyme-linked immunosorbent assays (ELISA). A luciferase reporter plasmid containing miRNA-146a/b promoter was tested in terms of p50/p65 regulation.
  
  
  RESULTS
  After P.g LPS treatment, NF-κB and Erk1/2 were strongly activated in HGFs. miRNA-146a/b, IL-1, IL-6 and TNF-α levels were down-regulated when NF-κB inhibitor was used. p50/p65 strongly activated miRNA-146a/b promoter as measured with the luciferase assay.
  
  
  CONCLUSIONS
  In TLR4 signalling in HGFs, both miRNA-146a and miRNA-146b are downstream targets of NF-κB, but not of AP-1 signalling. miRNA-146a/b expression was specifically dependent on NF-κB but not Erk1/2 or JNK signalling.
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, 639 Zhi Zao Ju Road, Shanghai, 200011 China ; Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Xie
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, 639 Zhi Zao Ju Road, Shanghai, 200011 China ; Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Shu
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, 639 Zhi Zao Ju Road, Shanghai, 200011 China ; Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
authors.forename: Shao-Yun
authors.initials: SY
authors.lastname: Jiang
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, 639 Zhi Zao Ju Road, Shanghai, 200011 China ; Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
authors.forename: Zhong-Chen
authors.initials: ZC
authors.lastname: Song
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, 639 Zhi Zao Ju Road, Shanghai, 200011 China ; Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
authors.forename: Qiu-Man
authors.initials: QM
authors.lastname: Guo
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, 639 Zhi Zao Ju Road, Shanghai, 200011 China ; Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
authors.forename: Jia-Chen
authors.initials: JC
authors.lastname: Dong
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, 639 Zhi Zao Ju Road, Shanghai, 200011 China ; Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
authors.forename: Zhi-Kai
authors.initials: ZK
authors.lastname: Lin
keywords: Human gingival fibroblasts; NF-κB; Pro-inflammatory cytokines; miRNA-146