TNF and gastric ulcer: In a naproxen-induced gastric ulceration rat model, oral administration of anthocyanins (20, 50, and 80 mg/kg b.w.)twice daily for 3 days attenuated the expression of pro-inflammatory cytokines TNF-α and IL-1β and activated the expression of metalloproteinase-2 (MMP-2), a zinc-dependent endoproteinase associated with inflammation [81].