Mechanism of Dahuang Zhechongwan in Inhibiting Silicosis in Mice via p38 MAPK/NF-κB/TGF-β1 Pathway / 中国实验方剂学杂志

ABSTRACT

Objective:To explore the effects and mechanism of Chinese classical prescription Dahuang Zhechongwan on silicosis in mice. Method:Thirty-six male Kunming mice of SPF grade were randomized into the normal control group， model control group， tetrandrine （Tet， 0.039 mg·kg^-1） group， as well as high- （1.560 g·kg^-1）， medium- （0.780 g·kg^-1）， and low-dose （0.390 g·kg^-1） Dahuang Zhechongwan groups， with six mice in each group. Mice in all groups except for the normal control group underwent static inhalation of silica （SiO₂） dust for 40 consecutive days to induce fibrosis. After 28 days of intervention with corresponding drugs， the mice were sacrificed to collect the serum and lung tissues， with the former used for detecting tumor necrosis factor-<italic>α</italic> （TNF-<italic>α</italic>）， interleukin-1<italic>β </italic>（IL-1<italic>β</italic>）， IL-6， and hydroxyproline （HYP） levels by enzyme-linked immunosorbent assay （ELISA） and the latter for observing the pathological changes. Meanwhile， the protein and mRNA expression levels of p38 mitogen-activated protein kinase （p38 MAPK）， nuclear transcription factor-<italic>κ</italic>B （NF-<italic>κ</italic>B）， transforming growth factor-<italic>β</italic>₁ （TGF-<italic>β</italic>₁）， <italic>α</italic>-smooth muscle actin （<italic>α</italic>-SMA）， Smad2， Smad3， and Smad7 in the lung tissues were determined by Western blot and real-time polymerase chain reaction （Real-time PCR）. Result:Compared with the normal group， the contents of TNF-<italic>α</italic>， IL-1<italic>β</italic>， IL-6 and HYP in the model group were significantly increased， the difference was statistically significant（<italic>P</italic><0.05，<italic>P</italic><0.01）； compared with the model group， the high-dose group of Dahuang Zhechongwan could significantly reduce the contents of TNF-<italic>α</italic>， IL-6 and HYP in the serum of mice（<italic>P</italic><0.05， <italic>P</italic><0.01）， indicating that Dahuang Zhechongwan could reduce the lung inflammation of silicosis mice. At the same time， compared with the normal group， the protein and mRNA expression levels of p38 MAPK， NF-<italic>κ</italic>B p65， TGF-<italic>β</italic>₁， <italic>α</italic>-SMA， Smad2 and Smad3 in the model group were significantly increased（<italic>P</italic><0.05，<italic>P</italic><0.01）， while the protein and mRNA expression levels of Smad7 were significantly decreased（<italic>P</italic><0.01）； compared with the model group， the protein and mRNA expression levels of p38 MAPK， NF-<italic>κ</italic>B p65， TGF-<italic>β</italic>₁， <italic>α</italic>-SMA， Smad2 and Smad3 in the high-dose Dahuang Zhechongwan group were significantly increased the protein and mRNA expression levels were significantly decreased（<italic>P</italic><0.05，<italic>P</italic><0.01）， while Smad7 protein and mRNA expression levels were significantly increased（<italic>P</italic><0.05，<italic>P</italic><0.01）. Conclusion:Dahuang Zhechongwan ameliorates the alveolar inflammation， extracellular matrix （ECM） deposition， and fibrosis in mice with silicosis possibly by regulating the p38 MAPK/NF-<italic>κ</italic>B/TGF-<italic>β</italic>₁ pathway.