tizoxanide and Inflammation

Traumatic brain injury (TBI) induced neuroinflammation is featured as excessive glial inflammatory activation and violent neurologic destruction and dysfunction. Massive microglia activation in situ and disrupt of blood-brain barrier contribute to severely collapsed nervous system. Tizoxanide (TIZ), a synthetic thiazolide derivative agent possessing a broad-spectrum anti-infective effect, currently shows a potential resistance against pathogens like bacteria, virus and parasites, while its underlying role in neuroinflammation is elusive. The study aimed to explore the effect of TIZ on neuroinflammation in vitro microglia.. Primary microglia were accepted to neuroinflammatory activation via lipopolysaccharide (LPS) administration. TIZ was conducted to pretreatment of microglia. Cell viability, inflammatory cytokines, chemotaxis, nitric oxide release, inflammation-related enzymes, and mitogen-activated protein kinase (MAPK) pathway activation in microglia were investigated respectively.. We demonstrated that TIZ administration attenuates inflammatory cytokines and chemokines through quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) of medium supernatant. In addition, TIZ reduces pro-inflammatory mediators and nitric oxide release in microglia. Furtherly, TIZ inhibits the level of p38/MAPK pathway in LPS stimuli, indicating that TIZ negatively regulates neuroinflammation via inhibiting p38/MAPK pathway.. TIZ is verified to be an anti-inflammation effect on neuroinflammation in microglia via downregulation of p38/MAPK pathway, which restrains inflammation by reduced inflammatory cytokines, chemokines and mediators and decreased nitric oxide release. To summarize, TIZ is considered to be a promising reagent to alleviate neuroinflammation targeting microglia in nervous system injury.

Topics: Animals; Cell Survival; Cells, Cultured; Female; Inflammation; Lipopolysaccharides; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Microglia; Nitric Oxide; p38 Mitogen-Activated Protein Kinases; Pregnancy; Thiazoles

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.

Topics: Animals; Anti-Inflammatory Agents; Cytokines; Inflammation; Lipopolysaccharides; Macrophages; Mice; Mitogen-Activated Protein Kinases; NF-kappa B; Nitrogen Oxides; RAW 264.7 Cells; Thiazoles