Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 48 7 2019 07 01 1292 1300 Hui WANG Department of Immunology, Qiqihar Medical University, Qiqihar 161000, P.R. China Shuhua LI Department of Traditional Chinese Medicine, The First Hospital of Qiqihar, Qiqihar 161000, P.R. China Houzhong LI Department of Pharmacology, Mudanjiang Medical University, Mudanjiang 157011, P.R. China Fengxia DU Department of Pathogen Biology, Qiqihar Medical University, Qiqihar 161000, P.R. China Jie GUAN Department of Immunology, Qiqihar Medical University, Qiqihar 161000, P.R. China Yanmin WU Department of Immunology, Qiqihar Medical University, Qiqihar 161000, P.R. China 2019 06 27 Background: We aimed to investigate the effect of probiotic VSL#3 on NF-κB and TNF-α in rats with colitis and the correlation with TLR4-NF-κB signal pathway. Methods: Sixty Sprague Dawley (SD) rats were divided into the control, model and therapy groups (n=20) according to the random number table. Rats in the model and therapy groups were modeled for colitis, and rats in the therapy group were intragastrically administered with probiotic VSL#3. The expression of TLR4 and NF-κB protein, and the levels of NF-κB, TLR4, and TNF-α mRNA in the colon tissue were detected. The concentration of TNF-α in the serum after modeling but before intragastric administration (T0), 3d (T1) and 7d after intragastric administration (T2) was detected. Results: The expression of TLR4 and NF-κB p65 protein, and the levels of TLR4, NF-κB, and TNF-α mRAN in the therapy group decreased (P < 0.001). At T0, T1, and T2, the concentration of TNF-α in the model and control groups increased (P < 0.001). TLR4 and NF-κB in the therapy group were positively correlated with TNF-α mRAN (P < 0.050).Conclusion: In conclusion, probiotic VSL#3 inhibits the expression of NF-κB and TNF-α in rats with colitis through TLR4-NF-κB signal pathway, so it is expected to be a first choice drug for the treatment of colitis. Conclusion: In conclusion, probiotic VSL#3 inhibits the expression of NF-κB and TNF-α in rats with colitis through TLR4-NF-κB signal pathway, so it is expected to be a first choice drug for the treatment of colitis.   https://ijph.tums.ac.ir/index.php/ijph/article/view/17589 https://ijph.tums.ac.ir/index.php/ijph/article/download/17589/6446