A comprehensive analysis of epigenetic mechanisms regulating inflammation-induced TNF-α gene expression by...

Biologic therapies targeting TNF-α in inflammatory and autoimmune diseases underscore its central role in pathological inflammation. Epigenetic mechanisms are increasingly recognized as critical modulators of disease-associated gene expression, and advancing epigenetic-based therapeutics requires deeper insight into the transcriptional networks governing inflammatory responses. Here, we investigate the epigenetic regulation of inflammation-induced TNF-α transcription and identify lead compounds that suppress TNF-α expression in human macrophages.

A small-molecule epigenetic inhibitor screen comprising 152 compounds was performed to assess their effects on LPS-induced TNF-α transcription in THP-1 monocyte-derived macrophages. TNF-α mRNA and protein levels were quantified using qRT-PCR and ELISA, respectively. The screen identified 20 potent inhibitors of TNF-α expression, representing six major classes of epigenetic regulators: HATs, BRDs, HDACs, HDMs, PRMT1, and PLK1. Protein-protein interaction network analysis revealed extensive crosstalk between these targets and key inflammatory signaling pathways, including NF-κB and MAPK. Follow-up validation of the top 10 candidates demonstrated dose-dependent suppression of TNF-α at both transcriptional and protein levels. These compounds also exhibited broad anti-inflammatory activity, suppressing IL-1β, IL-6, IL-8, IL-17A, and CCL2 expression, and showed cross-species efficacy in human (THP-1) and mouse (RAW264.7) macrophages. NF-κB reporter assays further indicated that their inhibitory effects are mediated, at least in part, through blockade of NF-κB activation.

This study identifies a regulatory network of epigenetic modifiers controlling TNF-α transcription and reveals conserved mechanisms governing inflammatory gene expression. The validated lead compounds possess potent anti-inflammatory properties and hold strong potential for therapeutic repurposing as modulators of TNF-α-driven inflammatory diseases.