T-5224

T-5224 is an inhibitor of c-fos/activator protein 1 (AP-1). It inhibits the DNA binding activity of c-fos/AP-1 without affecting the activity of C/EBPα, ATF2, MyoD, Sp1, and NF-κB/p65 in vitro. It shows inhibitory activity in a c-fos/AP-1 promoter luciferase assay without changing c-fos family protein expression levels in TNF-α-stimulated NIH/3T3 cells. Administration of T-5224 (30 mg/kg) inhibits the development of collagen-induced arthritis in mice through reduction of IL-1β production, neutrophil infiltration, and synovial cell proliferation. It reduces the inflammatory cytokine response in...