TNF and necrotizing enterocolitis: Sodium butyrate administration improved the body weight and survival rate of NEC mice; relieved intestinal pathological injury; reduced the intestinal expression of HMGB1, TLR4, NF-κB, interleukin- (IL-) 1β, IL-6, IL-8, and TNF-α; and increased the intestinal expression of IL-10 (P < 0.05).