RÉSUMÉ
Aim To explore the effect of Taohong Siwu Decoction on apoptosis and EMT of pulmonary fibrosis model rats by JAK2/STAT3 signaling pathway. Methods Forty SD rats were randomly divided into control group, model group, methylprednisolone group, Taohong Siwu Decoction low-concentration, high-concentration group respectively, with eight cases in each group. The intratracheal injection of bleomycin was applied to induce IPF rat models. HE and Masson staining were performed to observe the pathological changes of lung tissues in each group. ELISA was used to detect the contents of TNF-α, MMP-7 and TGFβ-l in serum of rats. Immunohistochemistry and Western blot were applied to detect the protein expression of JAK2, pJAK2, STAT3, p-STAT3, E-cadherin, α-SMA in lung tissues. RT-PCR was applied to detect the expression of JAK2, STAT3, Bcl2 and Bax genes in lung tissues. Results Compared with control group, the degree of alveolar inflammation and fibrosis degree, the contents of TNF-α, MMP-7 and TGFβ-1 in serum, the levels of JAK2, p-JAK2, STAT3, p-STAT3, α-SMA protein expression, JAK2, STAT3, Bax gene expression were up-regulated, and the levels of Bcl-2 gene and E-cadherin protein expression were down-regulated in lung tissues. Compared with model group, the degree of alveolar inflammation and fibrosis, the contents of TNF-α, MMP-7 and TGFβ-1 in serum, the levels of JAK2, p-JAK2, STAT3, p-STAT3, α-SMA protein expression, JAK2, STAT3 and Bax gene expression were reduced, while the levels of Bcl-2 gene and E-cadherin protein expression were elevated in Taohong Siwu Decoction high-concentration group. Conclusions Taohong Siwu Decoction may regulate JAK2/STAT3 signaling pathway, down-regulate Bax, α-SMA and up-regulate Bcl-2, E-cadherin expression to induce apoptosis and EMT in rat model of pulmonary fibrosis, thus playing an anti-pulmonary fibrosis role.