[Smad7 inhibits collagen expression in human hepatic satellite cells in vitro].
OBJECTIVE
To investigate the effect of Smad7 on the expressions of collagen I and alpha-smooth muscle actin (alpha-SMA) in HSC-T6 cell line activated by transforming growth factor-beta1 (TGF-beta1).


METHODS
HSC-T6 cells stably expressing M2-flag protein were selected after co-infection of the cells with pTRE-Smad7-M2-flag and pTet-on. The optimal dose of doxycycline for inducing Smad7 was determined, and the effects of Smad7 over-expression on the expressions of collagen I and alpha-SMA in the cells activated by TGF-beta1 and on Smad2/3 phosphorylation were evaluated using Western blotting.


RESULTS
The optimal dose of doxycycline for inducing Smad7 expression was 2 mg/L. Smad7 over-expression induced by doxycycline decreased the expressions of collagen I and alpha-SMA in HSC-T6 cells activated by TGF-beta1, and down-regulated the level of Smad2/3 phosphorylation.


CONCLUSIONS
Smad7 over-expression inhibits Smad2/3 phosphorylation, and decreases the expression of collagen I and alpha-SMA in HSC-T6 cells induced by TGF-beta1 to inhibit the progression of liver fibrosis.
Tang
Li-xia
LX
First People's Hospital of Foshan City, Guangdong 528000, China.
Yang
Guang
G
Tang
Jia-ju
JJ
D000199:Actins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism*; D015316:Genetic Therapy; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D008103:Liver Cirrhosis / Q000378:metabolism / Q000628:therapy; D051906:Smad7 Protein / Q000494:pharmacology*; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology
C541116:ACTA2 protein, human; D000199:Actins; D024042:Collagen Type I; C497806:SMAD7 protein, human; D051906:Smad7 Protein; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1