Tizoxanide Inhibits Inflammation in LPS-Activated RAW264.7 Macrophages via the Suppression of NF-κB and MAPK Activation
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Tizoxanide is the main active metabolite of nitazoxanide. Nitazoxanide and tizoxanide have a broad-spectrum anti-infective effect, including parasites, bacteria, and virus. In the present study, we investigated the anti-inflammatory effect of tizoxanide on lipopolysaccharide (LPS)-stimulated RAW264.7 cells and revealed underlying molecular mechanisms. The results showed that tizoxanide significantly suppressed production of NO as well as pro-inflammatory cytokines, such as IL-1β, IL-6, and TNF-α in dose-dependent manner. Meanwhile, the levels of gene expression of these cytokines were inhibited significantly by tizoxanide that was discovered using RT-PCR. The increased protein levels of inducible nitric oxide synthase, heme oxygenase-1, and cyclooxygenase-2 by LPS in the cells were also reduced by tizoxanide. Moreover, we found that tizoxanide inhibited the phosphorylation of IKK-α and degradation of IκB by LPS in macrophage cells. The increased protein levels of p65 induced by LPS in the cytoplasm and nucleus were both decreased by tizoxanide, and the nuclear translocation of p65 was also restrained in cell imaging. In addition, tizoxanide considerably also inhibited LPS-activated JNK, p38, and ERK phosphorylation in RAW264.7 cells. Taken together, our results suggested that tizoxanide exerts anti-inflammatory effects, by inhibiting the production of pro-inflammatory cytokines and suppressing of the activation of the NF-κB and the MAPK signaling pathways in LPS-treated macrophage cells.
KEY WORDStizoxanide RAW264.7 cells lipopolysaccharide anti-inflammation NF-κB MAPKs
This work is financially supported by the National Key Technology Research and Development Program of China (2015BAD11B00). This project is also supported in part by the National Natural Science Foundation of China (31872516) and the National Key Research and Development Program of China (2018YFD0500302).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no competing interests.
- 14.Olivera, A., T.W. Moore, F. Hu, A.P. Brown, A. Sun, D.C. Liotta, J.P. Snyder, Y. Yoon, H. Shim, A.I. Marcus, A.H. Miller, and T.W.W. Pace. 2012. Inhibition of the NF-κB signaling pathway by the curcumin analog, 3,5-Bis(2-pyridinylmethylidene)-4-piperidone (EF31): anti-inflammatory and anti-cancer properties. International Immunopharmacology 12: 368–377.CrossRefGoogle Scholar
- 16.Harausz, E.P., K.A. Chervenak, C.E. Good, M.R. Jacobs, R.S. Wallis, M. Sanchez-Felix, W.H. Boom, and TB Research Unit (TBRU) at Case Western Reserve University. 2016. Activity of nitazoxanide and tizoxanide against Mycobacterium tuberculosis in vitro and in whole blood culture. Tuberculosis (Edinburgh, Scotland) 98: 92–96.CrossRefGoogle Scholar
- 17.Stachulski, A.V., C. Pidathala, E.C. Row, R. Sharma, N.G. Berry, M. Iqbal, J. Bentley, S.A. Allman, G. Edwards, A. Helm, J. Hellier, B.E. Korba, J.E. Semple, and J.F. Rossignol. 2011. Thiazolides as novel antiviral agents. 1. Inhibition of hepatitis B virus replication. Journal of Medicinal Chemistry 54: 4119–4132.CrossRefGoogle Scholar
- 28.Mazzone, G.L., I. Rigato, and C. Tiribelli. 2010. Unconjugated bilirubin modulates nitric oxide production via iNOS regulation. Bioscience Trends 4: 244–248.Google Scholar
- 32.Baig, M.S., S.V. Zaichick, M. Mao, A.L. de Abreu, F.R. Bakhshi, P.C. Hart, U. Saqib, J. Deng, S. Chatterjee, M.L. Block, S.M. Vogel, A.B. Malik, M.E.L. Consolaro, J.W. Christman, R.D. Minshall, B.N. Gantner, and M.G. Bonini. 2015. NOS1-derived nitric oxide promotes NF-κB transcriptional activity through inhibition of suppressor of cytokine signaling-1. The Journal of Experimental Medicine 212: 1725–1738.CrossRefGoogle Scholar
- 41.Wu, X.F., Z.J. Ouyang, L.L. Feng, G. Chen, W.J. Guo, Y. Shen, X.D. Wu, Y. Sun, and Q. Xu. 2014. Suppression of NF-κB signaling and NLRP3 inflammasome activation in macrophages is responsible for the amelioration of experimental murine colitis by the natural compound fraxinellone. Toxicology and Applied Pharmacology 281: 146–156.CrossRefGoogle Scholar
- 44.Schreiber, J., R.G. Jenner, H.L. Murray, G.K. Gerber, D.K. Gifford, and R.A. Young. 2006. Coordinated binding of NF-kappaB family members in the response of human cells to lipopolysaccharide. Proceedings of the National Academy of Sciences of the United States of America 103: 5899–5904.CrossRefGoogle Scholar