TNF and colitis: The protective effect of green tea polyphenols was confirmed by an acetic acid-induced colitis model, in which EGCG (50 mg/kg/die, by oral gavage) improved rat mucosal inflammation by drastically decreasing TNF-α, IFN-γ, and NF-κB expression levels and reducing nitric oxide (NO) production and malondialdehyde activity [43].