Dahuang Zhechong pill alleviates pulmonary fibrosis by inhibiting apoptosis and epithelial-mesenchymal transition of type II alveolar epithelial cells in vitro and in vivo.

BACKGROUND AND AIM: Idiopathic pulmonary fibrosis (IPF) is a lung disorder with an increasing incidence and poor prognosis. This study aimed to explore the effect of Dahuang Zhechong pill (DHZCP) in pulmonary fibrosis and its underlying mechanisms. EXPERIMENTAL PROCEDURE: We assessed the effect of DHZCP on pulmonary fibrosis in vivo. Transcriptomic analyses were performed, and certain targets and mechanisms identified were validated in vivo. Additionally, we employed CoCl(2)-and TGF-β1-activated RLE-6TN cells to further investigate the effects and mechanisms of DHZCP in vitro. RESULTS AND CONCLUSION: The administration of DHZCP remarkably alleviated BLM-induced pulmonary fibrosis, reduced lung inflammation and fibrosis, and improved lung function in rats. The transcriptomic data revealed that DHZCP downregulated important pathways involved in pulmonary fibrosis. In vivo, DHZCP decreased epithelial-mesenchymal transition (EMT) and apoptosis in AEC II cells and activated the TGF-β1/Hedgehog and HIF-1 signalling pathways. In vitro findings confirmed that DHZCP alleviated EMT via TGF-β1/Hedgehog signalling pathway inhibition and reduced apoptosis of AEC II cells by inhibiting the HIF-1 signalling pathway. We found that DHZCP reduces pulmonary fibrosis by inhibiting EMT and apoptosis in AEC II cells through the inhibition of the TGF-β1/Hedgehog and HIF-1 signalling pathways. This study provides a new perspective and experimental basis for the potential use of DHZCP in the clinical management of pulmonary fibrosis.