title: Airway smooth muscle cells from ovalbumin-sensitized mice show increased proliferative response to TGFβ1 due to upregulation of Smad3 and TGFβRII.
abstract: OBJECTIVE
  This study aimed to elucidate the role of Transforming growth factor (TGF)-β1 signaling in the proliferation of airway smooth muscle cells (ASMCs).
  
  
  BACKGROUND
  TGF-β1 is an important cytokine in airway remodeling in asthma. However, results of studies focusing on the effect of TGFβ1 on proliferation of ASMCs are controversial.
  
  
  METHODS
  An allergic model that mimics airway remodeling in chronic asthma was established and primary ASMCs were cultured. Cell proliferation was detected by viable cell counting and Cell Counting Kit (CCK)-8 analysis. Expression and phosphorylation of Smad3, type 1 TGFβ receptor (TGFβRI), type 2 TGFβ receptor (TGFβRII), extracellular signal-regulated kinase (ERK)-1/2, p38 mitogen-activated protein kinase (MAPK), C-Jun N-terminal kinase (JNK) and AKT were detected by western blot. siRNAs were used to knock down Smad3 and TGFβRII.
  
  
  RESULTS
  Smad3 and TGFβRII were up-regulated in primary ASMCs isolated from ovalbumin (OVA)-sensitized mice as compared with ASMCs isolated from unsensitized control mice, which persisted for at least four passages. TGFβ1 stimulated proliferation of ASMCs isolated from OVA-sensitized mice, which was inhibited by specific siRNA targeting Smad3 or TGFβRII. However ASMCs from control mice showed no proliferative response to TGFβ1. TGFβ1-induced proliferation of ASMCs from OVA-sensitized mice was markedly attenuated by PD-98059, a specific ERK1/2 inhibitor. TGFβ1 induced ERK1/2 phosphorylation within 15 minute, which was partially blocked by specific inhibitor of Smad3 (SIS3).
  
  
  CONCLUSIONS
  ASMCs isolated from OVA-sensitized mice showed hyper-proliferation upon TGFβ1 stimulation. This might have been associated with up-regulated Smad3 and TGFβRII and mediated by ERK1/2 downstream to Smad3.
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.|b Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Jianting
authors.initials: J
authors.lastname: Shi
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.|b Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Ouyang
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Linjie
authors.initials: L
authors.lastname: Huang
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Lin
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Ruiyun
authors.initials: R
authors.lastname: Liang
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Lv
authors.affiliation: b Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Shanying
authors.initials: S
authors.lastname: Liu
authors.affiliation: a Department of Respiratory Medicine , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.|b Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation , Sun Yat-Sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.
authors.forename: Shanping
authors.initials: S
authors.lastname: Jiang
mesh_terms: D056151:Airway Remodeling / Q000502:physiology*; D000818:Animals; D001249:Asthma / Q000503:physiopathology*; D004195:Disease Models, Animal; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D008168:Lung / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D032389:Myocytes, Smooth Muscle / Q000473:pathology*; D010047:Ovalbumin / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000378:metabolism; D018125:Receptors, Transforming Growth Factor beta / Q000096:biosynthesis; D051900:Smad3 Protein / Q000096:biosynthesis; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D034741:RNA, Small Interfering; D018125:Receptors, Transforming Growth Factor beta; D051900:Smad3 Protein; D053773:Transforming Growth Factor beta1; D010047:Ovalbumin; D048049:Extracellular Signal-Regulated MAP Kinases
keywords: Airway smooth muscle cell; ERK1/2; Smad3; TGFβ1; asthma