TNF and ulcerative colitis: In fact, Al-Rejaie et al. [41] showed that pretreatment with naringenin (50 and 100 mg/kg per day), or with mesalazine (300 mg/kg per day) used as positive control, for seven days before the induction of ulcerative colitis (through the treatment of 4% acetic acid), decreased the levels of pro-inflammatory cytokines (i.e., TNF-α, IL-1β, and IL-6) and prostaglandin E2.