Compound Astragalus and Salvia miltiorrhiza extract inhibits cell proliferation, invasion and collagen synthesis in keloid fibroblasts by mediating transforming growth factor-β / Smad pathway.

The transforming growth factor (TGF)-β/Smad pathway plays a key role in keloid development. We have previously demonstrated that compound Astragalus and Salvia miltiorrhiza extract (CASE) inhibits liver fibrosis and reduces invasion capacity of HepG2 cells by mediating the TGF-β/Smad pathway. We therefore hypothesize that CASE may also exert antifibrotic effects in keloids by mediating the TGF-β/Smad pathway. To investigate the effects of CASE on cell proliferation, invasion and collagen synthesis in keloid fibroblasts, and to explore the effects of CASE on the TGF-β/Smad signal pathway in order to elucidate its mechanisms of action. The inhibitory effects of CASE on keloid fibroblasts were evaluated. Cell proliferation was studied by MTT assay; cell invasion was observed utilizing Transwell invasion chambers; and collagen synthesis in keloid fibroblasts was measured by (3) H-proline incorporation assay. Expression of proteins induced by TGF-β1 and their intracellular localization in keloid fibroblasts were investigated by Western blot and immunofluorescence, respectively. Plasminogen activator inhibitor-1 (PAI-1) transcriptional activity was measured by real-time reverse transcription-polymerase chain reaction. CASE significantly inhibited cell proliferation induced by newborn bovine serum as well as collagen synthesis and cell invasion induced by TGF-β1 in keloid fibroblasts, while it showed weak effects on normal fibroblasts. The phosphorylation of Smad2/3 was markedly reduced by CASE treatment, while CASE exhibited stronger inhibitory effects on linker region phosphorylation (pSmad2L and pSmad3L) compared with effects on C-terminal region phosphorylation (pSmad2C and pSmad3C). In addition, CASE blocked formation of Smad2/3/4 complexes and their nuclear translocation, but upregulated Smad7 expression in a dose-dependent manner. PAI-1 mRNA and protein levels were also suppressed by CASE treatment. These results suggest that CASE exhibits inhibitory effects on cell proliferation, invasion and collagen synthesis in keloid fibroblasts, and its mechanisms of action may involve the TGF-β/Smad pathway.

He S ，Yang Y ，Liu X ，Huang W ，Zhang X ，Yang S ，Zhang X ... -  《-》

Compound Astragalus and Salvia miltiorrhiza extract inhibits cell invasion by modulating transforming growth factor-beta/Smad in HepG2 cell.

Liu X ，Yang Y ，Zhang X ，Xu S ，He S ，Huang W ，Roberts MS ... -  《-》

Compound Astragalus and Salvia miltiorrhiza Extract exerts anti-fibrosis by mediating TGF-beta/Smad signaling in myofibroblasts.

Yang Y ，Yang S ，Chen M ，Zhang X ，Zou Y ，Zhang X ... -  《JOURNAL OF ETHNOPHARMACOLOGY》

Mechanisms of transforming growth factor beta(1)/Smad signalling mediated by mitogen-activated protein kinase pathways in keloid fibroblasts.

He S ，Liu X ，Yang Y ，Huang W ，Xu S ，Yang S ，Zhang X ，Roberts MS ... -  《-》

FK506 inhibits the enhancing effects of transforming growth factor (TGF)-β1 on collagen expression and TGF-β/Smad signalling in keloid fibroblasts: implication for new therapeutic approach.

  Keloid is a unique proliferative disorder of fibroblasts resulting from derailment of the typical wound healing process. Due to lack of animal models for therapeutic testing, treatment of keloids remains a clinical challenge. Transforming growth factor (TGF)-β1-related signalling plays a key role in keloid formation. As tacrolimus (FK506) has been reported to inhibit the effects of TGF-β1 on cultured fibroblasts, we hypothesized that FK506 may be useful in treating keloids. To explore the effects of FK506 on TGF-β1-stimulated keloid fibroblasts (KFs) in terms of proliferation, migration and collagen production and to investigate the regulatory pathways involved. Fibroblasts derived from keloids were treated with TGF-β1 with or without FK506. Relevant assays including 5-bromo-2'-deoxyuridine incorporation assay, in vitro scratch assay, reverse transcription-polymerase chain reaction (PCR), quantitative PCR and Western blotting were performed. The proliferation and migration of KFs were significantly higher than those of normal fibroblasts. FK506 markedly inhibited KF proliferation, migration and collagen production enhanced by TGF-β1. The increase in TGF-β receptor I and II expression in TGF-β1-treated KFs was suppressed by FK506 treatment. TGF-β1 increased the phosphorylation of Smad2/3 and Smad4 in KFs, and this enhancing effect was abrogated by FK506. In addition, FK506 significantly increased the expression of Smad7 which was suppressed by TGF-β1 treatment. Our results demonstrate that FK506 effectively blocks the TGF-β/Smad signalling pathway in KFs by downregulation of TGF-β receptors and suggest that FK506 may be included in the armamentarium for treating keloids.

Wu CS ，Wu PH ，Fang AH ，Lan CC ... -  《-》