Abstract:
OBJECTIVE To study the inhibitory effect and mechanism of curcumin and its derivatives A and B on TGF-β induced LX-2 cell fibrosis.
METHODS Established the liver fibrosis model of LX-2 cells induced by TGF-β(10 ng·mL−1).The effects on cell proliferation were detected by CCK-8. The effects on cell apoptosis was detected by flow cytometry. The effects on fibrosis related factors(Collagen I, Collagen Ⅳ, Fibronectin, Vimentin, α-SMA, PDGFRβ, TGFβR1, TGFβR2, MMP2, MMP9, TIMP1 and TIMP2) protein expression and gene transcription levels were detected by Western blotting and q-PCR.
RESULTS The curcumin and its derivative A and B had the inhibition effects on normal LX-2 cells, and the IC25 values were 15.7, 2.6, 10.2 μmol·L−1, respectively. Compared to the model group, the curcumin(15.7 μmol·L−1) and its derivative A(2.6 μmol·L−1) and B(10.2 μmol·L−1) had the significant inhibition effects on cell proliferation of the TGF-β induced LX-2 cells(P<0.05). The cell apoptosis rate of curcumin derivative B group was higher than the model group(P<0.05). Collagen I, Fibronectin, Vimentin, α-SMA, TGFβR1 and TIMP-1 protein expression levels in curcumin group were lower, while the protein expression level of MMP-9 was higher(P<0.05). The protein expression levels of Collagen I, Collagen IV, Fibronectin, Vimentin, α-SMA, TIMP-1 and TIMP-2 in curcumin derivative A group were lower, while the protein expression level of MMP-2 was higher(P<0.05). The protein expression levels of Collagen I, Collagen IV, Fibronectin, Vimentin, α-SMA, PDGFRβ, TGFβR1, TGFβR2, TIMP-1 and TIMP-2 in curcumin derivative B group were lower, while the protein expression level of MMP-2 was higher(P<0.05). The gene transcription levels of Collagen I, Fibronectin, α-SMA and TIMP-1 in curcumin group were lower(P<0.05). The gene transcription levels of Collagen I, Fibronectin and α-SMA in curcumin derivative A and B groups were lower(P<0.05).
CONCLUSION Curcumin and its derivatives A and B inhibit the abnormal activation and proliferation of TGF-β-induced LX-2 cells, inhibit the excessive secretion and accumulation of its extracellular matrix components, and promote its degradation, thus playing an anti-fibrotic effect in vitro, especially the curcumin derivative B.