Objective: To investigate the effect of quercetin on the expression of connective tissue growth factor (CTGF) and fibronectin (FN) in hepatic stellate cells (HSCs) stimulated with transforming growth factor (TGF)beta1.
Methods: HSCs of rat were isolated by in situ perfusion and gradients centrifugation; the activated HSCs were incubated with quercetin (10(-9)-10(-5) mol/L) for 24, 48 and 72 h. TGFbeta1 was detected by flow cytometry. The expression of CTGF was detected by reverse transcription-polymerase chain reaction (RT-PCR), and then FN was detected by immunohistochemistry.
Results: Quercetin (10(-8) to 10(-5) mol/L) inhibited the expression of TGFbeta1 in HSCs. TGFbeta1 expression decreased after the HSCs being incubated with quercetin (10(-7) mol/L) for 48 h (mean fluorescence: 13.33+/-2.44 and 18.08+/-2.54, t=16.52, P<0.01). TGFbeta1 increased the expression of CTGF mRNA in HSCs, but this effect was abrogated by quercetin (10(-7) mol/L) within 72 h. Quercetin (10(-7) mol/L) significantly inhibited the expression of FN in HSCs.
Conclusion: Quercetin may have an inhibitory effect on the signal pathways of TGFbeta1, including the expression of TGFbeta1, FN and CTGF.