Scaffold compound T4015 attenuates pulmonary fibrosis via suppressing JAK/STAT and NF-κB signaling

Pulmonary fibrosis (PF) is a life-threatening interstitial lung disease characterized by scarring and inflammation in lung tissues. Aberrant activation of the JAK/STAT and NF-κB signaling pathways is critical in initiating and sustaining the inflammatory processes that drive fibrotic progression. In this study, we identify a novel small-molecule compound, T4015, a 4-indolyl-2-phenylaminopyrimidine derivative, as a dual-pathway inhibitor targeting both JAK/STAT and NF-κB signaling. Dual-luciferase reporter assays demonstrate the potent inhibitory activity of T4015 against these pathways. T4015 effectively suppresses the phosphorylation of STAT3, JAK1, and TYK2 induced by IL-6 and IFN-β, while suppressing LPS-induced NF-κB activation in macrophages. Transcriptome sequencing and pathway enrichment analyses further confirm that T4015 downregulates multiple inflammation-related signaling cascades, including the JAK/STAT, NF-κB, TNF, IL-17, and Toll-like receptor pathways. In a mouse model of bleomycin-induced PF, T4015 treatment significantly improves survival, attenuates collagen deposition, and reduces the expression of pro-inflammatory and profibrotic markers such as IL-6, CCL2, and COL1. Molecular docking and target prediction analyses suggest that T4015 exhibits strong binding affinity for multiple kinases within the JAK/STAT and NF-κB networks, including JAK1, TYK2, JAK2, JAK3, RIPK1, IRAK1/4, TAB1, and ZAP70. Collectively, these results highlight T4015 as a promising therapeutic candidate for PF through its simultaneous inhibition of the JAK/STAT and NF-κB signaling pathways.