[Effect of lamivudine and silymarin on liver fibrosis-relevant factors in HBV transgenic mice with alcohol drinking].

To observe the role of lamividine and silymarin preventing and curing liver fibrosis-relevant factors induced by alcohol drinking in hepatitis B virus (HBV) transgenic mice (Tg mice).
 Methods: Forty HBV-Tg BALB/C mice with 1.3 copy were randomly divided into 4 groups: a control group, a model group, a lamivudine group and a silymarin group. Tg mice in control group were treated with normal saline via intragastric administration; Tg-mice in the model group were treated with 50% alcohol (5 mL/kg) once a day via intragastric administration; while Tg-mice in lamivudine group and silymarin group were treated with alcohol (5 mL/kg) plus laminvudine (100 mg/kg) and silymarin (200 mg/kg) once a day via intragastric administration respectively. All groups were raised for 10 weeks. The levels of HBV-DNA copy number, ALT, AST in serum, the degree of inflammation, the degree of fibrosis, the mRNA expression levels of TGF-β1, Smad3, Smad7 and connective tissue growth factor (CTGF), and the protein expression levels of TGF-β1, CTGF and α-SMA in liver tissue were detected. All the images were scanned with electronic computer and the data were analyzed with SPSS13.0 software.
 Results: Compared with the control group, liver injury were significantly aggravated, while HBV-DNA copies, mRNA levels of TGF-β1, Smad3, Smad7 and CTGF as well as the protein levels of TGF-β1, CTGF and α-SMA were significantly increased (P<0.05). Compared with the model group, liver injury were significantly attenuated in silymarine group and lamivudine group, while mRNA levels of TGF-β1, Smad3 and CTGF as well as the protein levels of TGF-β1, CTGF and α-SMA were significantly decreased; mRNA level of Smad7 was further increased (P<0.05); the levels of ALT and AST in serum were decreased in the silymarine group (P<0.05).
 Conclusion: Lamivudine and silymarin relieve the histological damage in the liver of alcohol-fed Tg mice. The mechanisms for the beneficial effects of lamivudine or silymarin might be related to inhibiting the expression of TGF-β1, Smad3 and CTGF, modulating the expression of Smads and suppressing the activation of HSC.