Effects Of Danshensu And Astragalus On The Signal Transduction Inside The Rat Hepatic Stellate Cells

Objective: To investigate the effects of Danshensu and Astragalus on the TGF-β/TβR/Smads signal transduction pathway of the hepatic stellate cells (HSC-T6) stimulated by transforming growth factorβ1 (TGF-β1) ; and to explore the anti-fibrosis mechanism of Danshensu and AstragalusMethods: The effects of Danshensu and Astragalus with or without TGF-β1 on the proliferation of rat hepatic stellate cells (HSC-T6) were observed by the MTT assay. The effects of Danshensu and Astragalus on theα–SMA expression and theⅠandⅢcollagen synthesis within the HSC-T6 stimulated with TGF-β1 were observed by staining method of immunocytochemical. The quantity of typeⅠandⅢcollagen secretion were measured by ELISA method.The expressions of TβRⅠ/Ⅱon the cellular membrane of HSC-T6 were observed by indirect immunofluorescence cell staining method and Western blot method. The changes of Smad2, 3 and 7 mRNA of the HSC-T6 cells treated by Danshensu or Astragalus with TGF-β1 were quantified by RT-PCR analysis.Results: (1) The inhibition effects of Danshensu or Astragalus at the concentrations of 0.0125mg/ml to 0.2mg/ml on the proliferation of HSC-T6 increased with the concentrations of Danshensu or Astragalus. (P﹤0.01); Danshensu or Astragalus had inhibition effects on the proliferation of HSC-T6 stimulated by TGF-β1 in a dose dependent manner. (P﹤0.01).The most effective concentrations for Danshensu and Astragalus were 0.0125mg/ml~0.05mg/ml. (2) Danshensu and Astragalus could decrease the expression ofα-SMA , the synthesis and the secretion of typeⅠ/Ⅲcollagen in HSC-T6 stimulated by TGF-β1 (P﹤0.01). (3) They could down-regulate the expression of TβRⅠ/Ⅱof the HSC-T6 cells, witch were positive correlated with the concentration of them(P﹤0.01); Danshensu had a stronger inhibition effect on TβRⅠthan Astragalus(P﹤0.01).(4)TGF-β1 could promote the expressions of Smad2, 3 and 7 mRNA in the HSC-T6. Danshensu and Astragalus could decrease the expressions of Smad2 /3mRNA (P﹤0.01), and increase the expression of Smad7 mRNA in the HSC-T6 treated by TGF-β1(P﹤0.01).Conclusion: In vitro experiments, it is showed that Danshensu and Astragalus could downregulate the expression of TβRⅠ/Ⅱon the menbrane of HSC-T6 stimulated by TGF-β1. They also decrease the expression of Smad2,3mRNA, while increased the expression of Smad7 mRNA.Danshensu and Astragalus have the inhibition effects on the activation and the proliferation of HSC-T6 and HSC-T6 promoted by TGF-β1. They also have the inhibition effects on the expression ofα-SMA, and on the synthesis or secretion of typeⅠ/Ⅲcollagen within the HSC-T6 stimulated by TGF-β1. That means Danshensu and Astragalus might be play a role in anti-hepatic fibrosis, through the TGF-β/TβR/Smads signal transduction pathway of HSC-T6.Danshensu had stronger inhibition effects than Astragalus on the proliferation of HSC-T6, the secretion of typeⅠ/Ⅲcollagen and the expression of TβRⅠin the HSC-T6 stimulated by TGF-β1.