title: Triptolide inhibits TGF-β1 induced proliferation and migration of rat airway smooth muscle cells by suppressing NF-κB but not ERK1/2.
abstract: BACKGROUND
  Airway remodeling contributes to increased mortality in asthma. We have reported that triptolide can inhibit airway remodeling in a mouse asthma model. In this study, we aimed to investigate the effect of triptolide on airway smooth muscle cells (ASMCs) proliferation, migration and the possible mechanism.
  
  
  METHODS
  Rat airway smooth muscle cells were cultured and made synchronized, then pretreated with different concentrations of triptolide before stimulated by TGF-β1. Cell proliferation was evaluated by cell counting and MTT assay. Flow cytometry was used to study the influence of triptolide on cell cycle. Migration was measured by Transwell analysis. Signal proteins (NF-κB p65 and ERK1/2) were detected by western blotting analysis. LDH releasing test and flow cytometry analysis of apoptosis were also performed to explore the potential cytotoxic or pro-apoptotic effects of triptolide.
  
  
  RESULTS
  Triptolide significantly inhibited TGF-β1 induced ASMC proliferation and migration (p<0.05). The cell cycle was blocked at G1/S-interphase by triptolide dose dependently. Western blotting analysis showed TGF-β1 induced NF-κB p65 phosphorylation was inhibited by triptolide pretreatment, but ERK1/2 was not affected. No cytotoxic or pro-apoptotic effects were detected under the concentration of triptolide we used.
  
  
  CONCLUSIONS
  Triptolide may function as an inhibitor of asthma airway remodeling by suppressing ASMCs proliferation and migration through inactivation of NF-κB pathway. This article is protected by copyright. All rights reserved.
authors.affiliation: Department of Respiratory Medicine, Sun Yat-Sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, 510120, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.forename: Jian-Ting
authors.initials: JT
authors.lastname: Shi
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Lv
authors.forename: Lin-Jie
authors.initials: LJ
authors.lastname: Huang
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Lin
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Rui-Yun
authors.initials: RY
authors.lastname: Liang
authors.forename: Yi-Qun
authors.initials: YQ
authors.lastname: Li
authors.forename: Shan-Ping
authors.initials: SP
authors.lastname: Jiang
keywords: NF-κB; airway smooth muscle cells; asthma; triptolide