Role of phosphatase and tensin homolog deleted on chromosome ten in a rat model of carbon tetrachloride-induced liver fibrosis and the effect of qi-tonifying and blood-activating prescription

Objective To investigate the role of phosphatase and tensin homology deleted on chromosome ten (PTEN) in a rat model of carbon tetrachloride (CCl4)-induced liver fibrosis and the molecular mechanism of action of qi-tonifying and blood-activating prescription in regulating PTEN and inhibiting liver fibrosis. Methods A total of 27 male Wistar rats were randomly divided into three groups, with 9 rats in each group. The rats in liver fibrosis group were treated with CCl4 to establish a model of liver fibrosis, and those in qi-tonifying and blood-activating prescription group were also treated with CCl4 to establish a model and then given a self-made qi-tonifying and blood-activating prescription containing Astragalus membranaceus, Salvia miltiorrhiza, and poria. The rats in the control group were given intraperitoneally injected olive oil. HE staining, Masson staining, and immunohistochemical staining of collagen type I alpha 1 (Col1A1) and collagen type Ⅳ (Col4) were performed to observe the degree of liver fibrosis and collagen deposition; qRT-PCR, immunohistochemistry, and Western blot were used to measure the expression of transforming growth factor-β1 (TGF-β1), PTEN, and downstream genes AKT, mTOR, and p70S6K. A one-way analysis of variance was used for comparison of continuous data between multiple groups and the least significant difference t-test was used for further comparison between any two groups. Results In the liver fibrosis group, liver pathology showed perisinusoidal fibrosis and fibrous tissue proliferation, collagen deposition, and formation of fibrous septum in the portal area; compared with the control group, the liver fibrosis group had significant increases in the mRNA and protein expression of TGF-β1, a significant reduction in the expression of PTEN, and significant increases in the mRNA and phosphorylated protein expression of AKT, mTOR, and p70S6K (all P＜0.01). The qi-tonifying and blood-activating prescription group had a marked improvement in liver fibrosis; compared with the liver fibrosis group, the qi-tonifying and blood-activating prescription group had a significant increase in the expression of PTEN (P＜0.01), significantly inhibited mRNA and protein expression of TGF-β1 (both P＜0.05), and significant reductions in the mRNA and phosphorylated protein expression of AKT, mTOR, and p70S6K (all P＜0.05). Conclusion Qi-tonifying and blood-activating prescription can prevent and reverse liver fibrosis, possibly by regulating the expression of PTEN and its downstream signal factors