The Mechanisms Of The Protective Effect Of MyD88 Inhibitor On Hepatic Ischemia-reperfusion Injury Via Suppressing Pyroptosis

Objective: To clarify the protective effect of TJ-M2010-5,an inhibitor of myeloid differentiation factor 88(My D88),on partial hepatic ischemia-reperfusion injury(IRI)in mice and its potential mechanism,to study the relationship between pyroptosis and disease occurrence and development in hepatic IRI,and to explore the effect of TJ-M2010-5 in the mice hepatic IRI model and its mechanism.Methods: The IRI model of partial hepatic fever in mice was successfully established by clamping the portal vein and hepatic artery of the partial hepatic lobe in mice after 1 h ischemia and 6 h reperfusion.By detecting the liver function,histopathology,hepatocyte apoptosis,inflammatory cell infiltration,the production of systemic inflammatory factors,and the expression of related proteins in mice,we studied whether My D88 inhibitor has a protective effect on IRI of the liver with pyroptosis of macrophages,detected the occurrence of pyroptosis of liver tissue cells in each group of mice to study the relationship between pyroptosis of cells in IRI of liver and the occurrence and development of diseases,and even purified Kupffer cells in mouse liver tissue to clarify which cells pyroptosis occurred during hepatic IRI.In vitro,bone marrow-derived macrophages(BMDMs)treated with lipopolysaccharide(LPS)and adenosine triphosphate(ATP)were used to simulate the inflammatory environment in mice model of hepatic IRI,and the mechanism of hepatic IRI inflammation was discussed by detecting the synthesis and release of inflammatory factors and the expression of related proteins in BMDMs cells.As an in vitro model of cell apoptosis,the influence of TJ-M2010-5 on cell apoptosis of BMDMs and its specific mechanism were explored by detecting the death of BMDMs,the expression of cell apoptosis-related indicators,the level and distribution of intracellular LPS and high mobility group protein B1(HMGB1).Results: TJ-M2010-5 has a strong protective effect on hepatic IRI by down-regulating TLR4(Toll-like receptor 4,TLR4)/My D88/NF-κB(nuclear factor kappa-b,NF-κB)signaling pathway,including liver function,histology,hepatocyte apoptosis,inflammatory cell infiltration and the production of systemic inflammatory factors.At the same time,TJM2010-5 can reduce Pyroptosis and the consumption of hepatic macrophages caused by IRI.When the liver experiences IRI,pyroptosis mainly occurs in Kupfer cells,and TJ-M2010-5can alleviate pyroptosis of Kupfer cells.In vitro,TJ-M2010-5 can significantly reduce the expression and release of inflammatory cytokines in BMDMs.TJ-M2010-5 has no obvious effect on hepatocyte apoptosis induced by hypoxia and reoxygenation,but it can alleviate hepatocyte injury induced by the cell culture supernatant of inflammatory-activated BMDMs.TJ-M2010-5 resisted classical pyroptosis in BMMs by reducing nuclear translocation of NF-κB and inhibiting the activation of the TLR4/My D88/NF-κB signaling pathway,resisted non-classical pyroptosis in BMMs by reducing the release of HMGB1 and inhibiting the endocytosis of LPS-HMGB1 complex.Conclusion: 1.TJ-M2010-5 can significantly improve the liver injury caused by hepatic ischemia-reperfusion;2.TJ-M2010-5 can reduce the inflammatory reaction caused by IRI in the liver;3.TJ-M2010-5 inhibited the Pyroptosis of classical and nonclassical cells in liver tissues(mainly Kupffer cells)in hepatic IRI;4.TJ-M2010-5 inhibited the activation of BMDMs to indirectly protect hepatocytes;5.TJ-M2010-5 reduces the classical Pyroptosis of BMDMs by inhibiting the activation of the TLR4/My D88/NF-κB signal pathway;6.TJ-M2010-5 can alleviate the nonclassical Pyroptosis of BMDMs by reducing the endocytosis of the LPS-HMGB1 complex.Therefore,TJ-M2010-5 may inhibit the activation of the TLR4/My D88/NF-κB signaling pathway to alleviate the cell death of Kupffer cells in hepatic IRI and alleviate the inflammatory reaction in liver tissue,to achieve the purpose of protecting hepatic IRI.