Digestive Diseases and Sciences

, Volume 61, Issue 7, pp 1961–1971 | Cite as

Knockdown of Astrocyte Elevated Gene-1 Inhibits Activation of Hepatic Stellate Cells

  • Lei Chen
  • Yong-ze Guo
  • Ai-di Li
  • Jun-ji Ma
  • Hui-yao Hao
  • Di Zhang
  • Yan Wang
  • Chen-guang Ji
  • Wei Qi
  • Jia Wang
  • Hui-qing Jiang
Original Article



Astrocyte elevated gene-1 (AEG-1) is a positive regulator of tumorigenesis and a valuable prognostic marker of a diverse array of cancers, including liver cancer; however, the relationship between AEG-1 and hepatic fibrogenesis is not known.


The objective of this study was to explore the expression of AEG-1 during hepatic fibrogenesis and determine how AEG-1 regulates the profibrogenic phenotype of hepatic stellate cells (HSCs).


The levels of AEG-1 were monitored in the fibrotic livers and transforming growth factor-β (TGF-β)- or lipopolysaccharide (LPS)-stimulated HSCs. The expression of AEG-1 was knocked down by lentivirus-mediated short hairpin RNA in HSCs, and collagen expression, proliferation assays, apoptosis induction studies, and migration assays were simultaneously conducted in vitro.


AEG-1 expression was increased in the fibrotic livers. At the cellular level, TGF-β or LPS stimulation, which caused HSC activation, induced AEG-1 expression in HSC-T6 and primary rat HSCs (P < 0.05). Knockdown of AEG-1 inhibited collagen I and α-smooth muscle actin expression (P < 0.05), reduced cell proliferation (P < 0.05) and motility (P < 0.05), and induced cell apoptosis (P < 0.05) in HSCs. This antifibrotic effect caused by lack of AEG-1 was associated with the inactivation of PI3K/Akt and the mitogen-activated protein kinase pathway.


Knockdown of AEG-1 suppressed the activation of HSCs by modulating the phenotype and inducing apoptosis. AEG-1 might be a potential target in treatment of hepatic fibrosis.


Astrocyte elevated gene-1 Liver fibrosis Hepatic stellate cell Activation 



This study was supported by the National Natural Science Foundation of China (No. 81170411).

Compliance with ethical standards

Conflicts of interest

The authors declare no conflict of interest associated with this study.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Lei Chen
    • 1
  • Yong-ze Guo
    • 1
  • Ai-di Li
    • 1
  • Jun-ji Ma
    • 1
  • Hui-yao Hao
    • 2
  • Di Zhang
    • 1
  • Yan Wang
    • 1
  • Chen-guang Ji
    • 1
  • Wei Qi
    • 1
  • Jia Wang
    • 1
  • Hui-qing Jiang
    • 1
  1. 1.Department of GastroenterologyThe Second Hospital of Hebei Medical University, Hebei Key Laboratory of Gastroenterology, Hebei Institute of GastroenterologyShijiazhuangChina
  2. 2.Department of Endocrinology and MetabolismThe Second Hospital of Hebei Medical UniversityShijiazhuangChina

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