Published online Oct 28, 2014. doi: 10.3748/wjg.v20.i40.14875
Revised: June 25, 2014
Accepted: July 16, 2014
Published online: October 28, 2014
AIM: To observe the effect of Danshao Huaxian capsule (DHC) on the expression of Gremlin and bone morphogenetic protein-7 (BMP-7) in the liver of hepatic fibrosis rats.
METHODS: A total of 75 male Wistar rats were randomly divided into a normal control group (A), a CCl4-induced hepatic fibrosis model group (B), a natural recovery group (C), a low-dose DHC-treated group (D), and a high-dose DHC-treated group (E), with 15 rats in each group. Liver fibrosis was induced by subcutaneous injections of carbon tetrachloride (CCl4) and a high-lipid/low-protein diet for 8 wk, except for the rats in group A. Then, the rats in the two DHC-treated groups were administered 0.5 and 1.0 g/kg DHC by gastrogavage once per day for 8 successive weeks, respectively. By the end of the experiment, the level of transforming growth factor β1 (TGF-β1) in the liver homogenate was determined by an enzyme-linked immunosorbent assay. The mRNA and protein expression of Gremlin and BMP-7 in the liver tissue was determined by reverse-transcription polymerase chain reaction, an immunohistochemical assay, and Western blot analysis.
RESULTS: Compared with group A, the level of TGF-β1 and the mRNA and protein expression of Gremlin were significantly higher in group B (TGF-β1: 736.30 ± 24.40 μg/g vs 284.20 ± 18.32 μg/g, P < 0.01; mRNA of Gremlin: 80.40 ± 5.46 vs 49.83 ± 4.20, P < 0.01; positive protein expression rate of Gremlin: 38.46% ± 1.70% vs 3.83% ± 0.88%, P < 0.01; relative protein expression of Gremlin: 2.81 ± 0.24 vs 0.24 ± 0.06, P < 0.01), and the mRNA and protein expression of BMP-7 was significantly lower in group B (mRNA: 54.00 ± 4.34 vs 93.99 ± 7.03, P < 0.01; positive protein expression rate: 28.97% ± 3.14% vs 58.29% ± 6.02, P < 0.01; relative protein expression: 0.48 ± 0.31 vs 1.05 ± 0.12, P < 0.01). Compared with groups B and C, the degree of hepatic fibrosis was significantly improved, and the level of TGF-β1 and the mRNA and protein expression of Gremlin were significantly lowered in the two DHC-treated groups (TGF-β1: 523.14 ± 21.29 μg/g, 441.86 ± 23.18 μg/g vs 736.30 ± 24.40 μg/g, 651.13 ± 15.75 μg/g, P < 0.01; mRNA of Gremlin: 64.86 ± 2.83, 55.82 ± 5.39 vs 80.40 ± 5.46, 70.37 ± 4.01, P < 0.01; positive protein expression rate of Gremlin: 20.78% ± 1.60%, 17.43% ± 2.02% vs 38.46% ± 1.70%, 29.50% ± 2.64%, P < 0.01; relative protein expression of Gremlin: 1.95 ± 0.26, 1.65 ± 0.20 vs 2.81 ± 0.24, 2.22 ± 0.63, P < 0.01), and the mRNA and protein expression of BMP-7 was higher in the two DHC-treated groups (mRNA: 73.52 ± 4.56, 81.78 ± 5.38 vs 54.00 ± 4.34, 62.28 ± 4.51, P < 0.01; positive protein expression rate: 41.44% ± 4.77%, 47.49% ± 4.59% vs 28.97% ± 3.14%, 35.85% ± 3.50%, P < 0.01; relative protein expression: 0.71 ± 0.06, 0.81 ± 0.07 vs 0.48 ± 0.31, 0.60 ± 0.37, P < 0.01).
CONCLUSION: The therapeutic mechanism of DHC for hepatic fibrosis in rats may be associated with inhibition of the expression of Gremlin and up-regulation of the expression of BMP-7.
Core tip: Hepatic fibrosis, as a refractory disease, represents a current threat to global health. To date, no ideal drug therapies have been identified, and drugs for liver fibrosis remain in the exploratory stage of development. Previous experimental and clinical studies showed that Danshao Huaxian capsule (DHC, originally called Handan Ganle) demonstrated efficacy in treating liver fibrosis. In this study, the effect of DHC on the expression of Gremlin and bone morphogenetic protein 7 (BMP-7) in a liver fibrosis rat model was observed to explore its potential mechanism for treating liver fibrosis. We found that the therapeutic mechanism of DHC for hepatic fibrosis in rats may be associated with inhibition of the expression of Gremlin and up-regulation of the expression of BMP-7.