title: Anti-inflammatory role of microRNA let-7c in LPS treated alveolar macrophages by targeting STAT3.
abstract: OBJECTIVE
  To explore the expression of microRNA (miRNA) let-7c and its function in chronic obstructive pulmonary disease (COPD) and alveolar macrophage cells.
  
  
  METHODS
  Real time PCR was performed to detect the expression of miRNA let-7c in the lung tissue of COPD patients and COPD model in mice. MiRNA let-7c was overexpressed in alveolar macrophages isolated from mice and its effect was measured by the production of pro-inflammation cytokines and the protein level of signal transducer and activator of transcription 3 (STAT3) as well as phosphorylation level of STAT3 after LPS stimulation. Luciferase assay was used to detect the binding of miRNA let-7c and 3'UTR of STAT3.
  
  
  RESULTS
  MiRNA let-7c expression was significantly lower in patients with COPD compared with control group, and the similar result was found in COPD mice and LPS stimulated alveolar macrophages. Overexpression of miRNA let-7c in alveolar macrophages inhibited LPS-induced increasing of tumor necrosis factor alpha, interleukin-6 and interleukin-1β. Luciferase assay showed STAT3 was a targeting of miRNA let-7c in alveolar macrophages.
  
  
  CONCLUSIONS
  MiRNA let-7c low expression in COPD can regulate inflammatory responses by targeting STAT3 in alveolar macrophage, which may provide a new target for COPD treatment strategies.
authors: Department of Healthy, First Affiliated Hospital of Chongqing Medical University, Chongqing, China. Electronic address: asafdgd111@126.com.
authors: Ji-Hui
authors: JH
authors: Yu
authors: Department of Healthy, First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors: Li
authors: L
authors: Long
authors: Department of Healthy, First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors: Zhi-Xiao
authors: ZX
authors: Luo
authors: Department of Healthy, First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors: Lin-Man
authors: LM
authors: Li
authors: Department of Healthy, First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors: Jie-Ru
authors: JR
authors: You
keywords: Chronic obstructive pulmonary disease; Inflammation; Let-7c; Macrophage; STAT3