TNF and colitis: As illustrated in Fig. 2A–F, the levels of proinflammatory cytokines, including TNF-α, IL-6, interferon-γ (IFN-γ), interleukin-18 (IL-18) and interleukin-17a (IL-17a), were significantly increased in DSS-induced colitis mice (P < 0.05 vs. CON).