CTBP1 can promote the activation and proliferation of lung fibroblasts through ZEB1. CTBP1 promotes lung fibroblast activation through ZEB1, thereby increasing excessive deposition of ECM and aggravating IPF. Toosendanin may be a potential treatment for pulmonary fibrosis. The results of this study provide a new basis for clarifying the molecular mechanism of pulmonary fibrosis and developing new therapeutic targets.