Study on the mechanism of anti-pulmonary fibrosis action of Jingfang granules based on the Keap1-Nrf2-GPX4 pathway.

Abstract

ETHNOPHARMACOLOGICAL RELEVANCE: Jingfang granules (JF) is derived from the original formula of Jingfang Baidu Powder. Modern pharmacological studies have shown its antipyretic, analgesic, and anti-inflammatory effects. It has been clinically used to treat viral respiratory infections and human mycoplasma pneumonia, with proven efficacy and significant improvement in patients' clinical symptoms. However, the mechanism by which JF treats pulmonary fibrosis (PF) remains unclear. RESEARCH OBJECTIVES: This study aims to investigate the therapeutic efficacy of JF in PF and elucidate its potential therapeutic mechanisms. MATERIALS AND METHODS: To explore the therapeutic potential of JF in PF, we constructed a mouse model of PF induced by bleomycin (BLM) and an integrated in vitro co-culture system consisting of MLE-12 cells and primary mouse pulmonary fibroblasts, combined with serum pharmacology of traditional Chinese medicine. The study evaluated the effects of JF on pathological alterations in vivo and its regulatory influence on cell proliferation and fibrotic processes in vitro. In addition, the activation of the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2)-glutathione peroxidase 4 (GPX4) signaling pathway was examined, and the direct binding interaction between JF and Keap1 was verified. RESULT: JF significantly alleviated BLM-induced PF in mice. In murine lung epithelial cells (MLE-12) and primary pulmonary fibroblasts, JF demonstrated the ability to directly bind to Keap1, thereby promoting Keap1 autophagic degradation. This activation of Keap1-Nrf2-GPX4 effectively restrained cell proliferation and migration, thereby mitigating fibrotic progression. CONCLUSION: In summary, JF exerts its anti-fibrotic effects by targeting Keap1 and competitively disrupting the Keap1-Nrf2 interaction, thereby promoting Nrf2 protein translocation into the nucleus. This mechanism provides experimental evidence supporting its clinical application and new drug development.