Compound 8A Inhibited NLRP3 Inflammasome Activation And Attenuated Inflammatory Disease Via Directly Targeting ASC

THESIS : Compound 8A inhibited NLRP3 inflammasome activation andattenuated inflammatory disease via directly targeting ASC SPECIALIZATION: Immunopharmacology POSTGRADUATE: Jianhua Gao MENTOR: Wenjie Guo,Assocaited Professor,Qiang Xu,ProfessorABSTRACTIt has been reported that the NLRP3 inflammasome plays critical roles in the initiation and progression of diverse inflammatory diseases.Inhibition of the NLRP3 inflammasome signal has been shown to be effective in attenuating septic shock,peritonitis,Alzheimer’s disease,atherosclerosis,multiple sclerosisand gout and other diseases.Thus,the NLRP3 inflammasome is an excellent target for the treatment of multiple inflammatory diseases.In the first chapter,we reviewed the role of NLRP3 in inflammatory disease and the development of drug development in the inflammatory disease.Studies have shown that NLRP3 inflammasome plays an important role in many inflammatory diseases and is involved in the occurrence and development of a variety of diseases.NLRP3 inflammasome is a potential target for the inhibition of related diseases.In the second chapter,we screened a series of compounds by assaying their inhibition rate on IL-1β which was produced by LPS primed ATP activated THP-1 cells.Previously,spirodalesol from Daldinia eschscholzii was proposed as an NLRP3 inflammasome activation inhibitor.In order to identify its direct target for NLRP3 inhibition,a series simplified structural analogue was synthesized and screened.Compound 8A was identified as a most potent for NLRP3 inflammasome inhibition,which selectively inhibited Signal II but not Signal I of NLRP3 inflammasome activation.The activation of CASPl was also inhibited,and the compound 8A had no effect on mitochondrial homeostasis.Finally,it was found that compound 8A inhibited the recruitment of NLRP3 to ASC and inhibited the oligomerization of ASC.Compound 8A targeted ASC to inhibit the activation of NLRP3 inflammasome,and its target was verified.In the third chapter,the therapeutic effect of compound 8A was explored through LPSinduced murine endotoxemia model and MSU-induced peritonitis and gout model.Our experimental results showed that compound 8A attenuated sepsis in mice and inhibited activation of CASP1 in colonic tissues.In MSU-induced peritonitis and gout models,compound 8A reduced infiltration of neutrophils and inhibited activation of CASP1 in macrophages.In other words,compound 8A alleviates murine sepsis,peritonitis and gout with a possible mechanism of NLRP3 inflammasome inactivation.In conclusion,we found that compound 8A inhibits NLRP3 inflammasome by targeting ASC,which provides a new research idea for exploring the activation of NLRP3 inflammasome.Our findings provide evidence for the possible development of 8A as a lead compound for sepsis or other inflammasome-driven inflammatory diseases.