Effect of Exogenous Fetuin-A on TGF-β/Smad Signaling in Hepatic Stellate Cells

Objective. To explore the effects of low concentration of exogenous fetuin-A intervention on TGF-β1 induced LX2 cells through detection of the expression of mRNA and protein of Smad2, Smad3, and Smad7. Methods. MTT assay was used to detect the LX2 cells proliferation and the regression equation calculating software was applied to determine IC₅₀ of fetuin-A. RT-PCR was used to determine the relative content of Smad2, Smad3, and Smad7 mRNA in LX2 cells. Western blot was used to detect the LX2 cells relative content of Smad2, Smad3, Smad7 protein expression, respectively. Results. The analysis from RT-PCR and western blot showed that when compared with the other groups TGF-β1 + fetuin-A group increased the expression of Smad2 and Smad3 while decreased the expression of Smad7 (P < 0.05). Conclusion. Fetuin-A may improve the excessive activation of hepatic stellate cells which is caused by an enhanced positive regulation of Smad2 and Smad3 protein and the deficiency in negative regulation of Smad7 protein. This is through inhibiting the expression of Smad2 and Smad3 gene and promoting the expression of Smad7 gene. As a result, the development of liver fibrosis will be reduced.