TNF and rheumatoid arthritis: In an in vivo study with RA-induced DBA-1/J male mice, mangiferin (a natural polyphenol found especially in mangoes) suppressed the expression of IL-1β, IL-6, TNF-α, and receptor activator of NF-κB ligand (RANKL) via the activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and the inhibition of NF-κB [175].