Archives of Dermatological Research

, Volume 303, Issue 8, pp 563–572 | Cite as

Asiaticoside suppresses collagen expression and TGF-β/Smad signaling through inducing Smad7 and inhibiting TGF-βRI and TGF-βRII in keloid fibroblasts

  • Bing Tang
  • Bin Zhu
  • Yueying Liang
  • Liangkuan Bi
  • Zhicheng Hu
  • Bin Chen
  • Kai Zhang
  • Jiayuan Zhu
Original Paper


Asiaticoside (ATS) isolated from the leaves of Centella asiatica possesses strong wound-healing properties and reduces scar formation. However, the specific effects of asiaticoside on the formation of keloidal scars remain unknown. In the present study, we evaluated the in vitro effects of asiaticoside on the proliferation, collagen expression, and transforming growth factor (TGF)-β/Smad signaling of keloid-derived fibroblasts. Fibroblasts isolated from keloid tissue and normal skin tissues were treated with asiaticoside at different concentrations. Afterwards, they were subjected to RT-PCR and Western blot analyses. The inhibitory effects of asiaticoside on fibroblast viability were assayed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Asiaticoside decreased fibroblast proliferation in a time- and dose-dependent manner. It also inhibited type I and type III collagen protein and mRNA expressions. In addition, asiaticoside reduced the expression of both TGF-βRI and TGF-βRII at the transcriptional and translational level. Moreover, it increased the expression of Smad7 protein and mRNA. However, asiaticoside did not influence the expression of Smad2, Smad3, Smad4, phosphorylated Smad2, and phosphorylated Smad3. Taken together, these results suggest that asiaticoside could be of potential use in the treatment and/or prevention of hypertrophic scars and keloids.


Asiaticoside Transforming growth factor-β Smad Collagen Keloid 



This work was supported by National Natural Science Foundation of China Grants 30973128; Natural Science Foundation of Guangdong Province Grants 7001657 and 8151008901000082; Medical Science Research Foundation of Guangdong Province Grants B2007042.


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Bing Tang
    • 1
  • Bin Zhu
    • 1
  • Yueying Liang
    • 1
  • Liangkuan Bi
    • 1
  • Zhicheng Hu
    • 1
  • Bin Chen
    • 1
  • Kai Zhang
    • 1
  • Jiayuan Zhu
    • 1
  1. 1.Department of BurnsThe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina

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