Interventional effect of asiaticosdide on rats exposed to silica dust / 中华劳动卫生职业病杂志

Objective: To investigate the effect of asiaticoside for fibrosis in lung tissues of rats exposed to silica and to explore its possible mechanism. Methods: 144 SD male rats were randomly divided into control group, model group, positive drug control group, asiaticoside high-dose group, medium-dose group and low-dose group, each group included 24 rats. Rats in the control group were perfused with 1.0 ml of normal saline, and the other groups were given 1.0 ml 50 mg/ml SiO(2) suspension. Gavage of herbal was given from the next day after model establishment, once a day. Rats in the positive drug control group were administration with 30 mg/kg tetrandrine and rats in the low-dose group, medium-dose group and high-dose group were given 20 mg/kg, 40 mg/kg and 60 mg/kg asiaticoside for fibrosis respectively. Rats in the control group and the model group were given 0.9% normal saline. The rats were sacrificed in on the 14th, 28th and 56th day after intragastric administration and collect the lung tissues to detect the content of hydroxyproline, TGF-β(1) and IL-18, observe the pathological changes of the lung tissues by HE and Masson staining and determine the expressions of Col-I, a-SMA, TGF-β in lung tissues by Western Blot. Results: On the 14th day, 28th day and 56th day after model establishment, the lung tissues of rats in the model group showed obvious inflammatory response and accumulation of collagen fibers, and the degree of inflammation and fibrosis increased with time. The intervention of asiaticoside could effectively inhibit the pathological changes of lung tissues. The contents of hydroxyproline, IL-18 and TGF-β1 in lung tissues of model group were higher than those in the control group (P<0.05) , while the level of hydroxyproline, IL-18 and TGF-β1 in asiaticoside groups were significantly decreased, and the difference was statistically signicant (P<0.05) . Compared with the control group, the expression levels of Col-I, TGF-β1and α-SMA in lung tissue of model group were increased (P<0.05) , while the expression level of Col-I, TGF-β1 and α-SMA were decreased after the intervention of asiaticoside, and the difference was statistically signicant (P<0.05) . Conclusion: Asiaticoside can inhibit the increase of Col-I, TGF-β1 and α-SMA content in the SiO(2)-induced lung tissues of rats, reduce the release of TGF-β1 and IL-18 inflammatory factors in lung tissue, and then inhibit the synthesis and deposition of extracellular matrix in rat lung tissue, and improve silicosis fibrosis.

Effect of Tetrandrine on Col-I and FN in TGF-β1-induced MRC-5 Cells / 中国实验方剂学杂志

Objective:To investigate the effect of tetrandrine on transforming growth factor-β1（TGF-β1）stimulated MRC-5 cells. Method:Different concentrations of TGF-β1 (0, 2.5, 5, 10, 20, 40 μg·L-1) were applied to MRC-5 cells. Proliferation toxicity of TGF-β1 to MRC-5 was detected by cell counting kit-8 (CCK-8) method. Detection of alpha smooth muscle actin (α-SMA) and Vimentin's expression levels in MRC-5 by Western blot. Detection of changes of collagen I(Col-I) and fibronectin (FN)'s expression levels in MRC-5 supernatants by enzyme linked immunosorbent assay(ELISA) kit. And the appropriate concentration of TGF-β1 activated MRC-5 cells was screened. The appropriate concentration of TGF-β1 and different concentrations of Tet (0, 2.5, 5, 10, 20, 40 μmol·L-1) were applied to MRC-5 cells, and CCK-8 method was used to screen safe concentration again. Western blot was used to detect changes in α-SMA and Vimentin expression levels in MRC-5 cells, and ELISA method to detect changes in Col-I and FN in MRC-5 cell supernatant. Result:Compared with the blank group, 20，40 μg·L-1 of TGF-β1 had toxic effects on MRC-5 cells at 24 hours (P<0.05), and 10，20，40 μg·L-1 of TGF-β1 had toxic effects on MRC-5 cells at 48 h (P<0.05).When Tet is added for 24 h, the half inhibitory concentration (IC50) value was 14.07 μmol·L-1, and when cultured for 48 h, the IC50 value was 7.51 μmol·L-1. Compared with the blank group, the relative contents of α-SMA, FN and Col-I in the 5 μg·L-1 of TGF-β1 group were obviously increased (P<0.05), and the relative contents of Vimentin were significantly increased (P<0.01), and the relative contents of FN and Col-I, α-SMA and Vimentin in 10 μg·L-1 group were significantly increased (P<0.01). 10 μg·L-1 of TGF-β1 was co-cultured with Tet at different concentrations. Compared with the TGF-β1 group, the relative levels of α-SMA, Vimentin and FN in the 5 μmol·L-1 of Tet group were significantly reduced (P<0.01), and the relative levels of Col-I were obviously reduced (P<0.05). In the Tet 10 μmol·L-1 group, the relative contents of the α-SMA, Vimentin, FN and Col-I were significantly reduced (P<0.01). Conclusion:TGF-β1 can increase the levels of Col-I, FN and other extracellular matrices in MRC-5 cells, and Tet can effectively inhibit the occurrence of this change. It is suggested that Tet may inhibit secreting extracellular matrix of fibroblasts in the formation of pulmonary fibrosis.