Naringenin protects LPS-induced dopaminergic neurons damage through mediating NLRP3 inflammasome

OBJECTIVE To research the effect of naringenin（NAR） on LPS-induced dopaminergic neurons damage and its potential mechanism.METHODS Rats were randomly divided into the following six groups（n=10）:control（0.9% NaCl）,NAR alone（100 mg·kg-1）,LPS（5 μg）,LPS+NAR（50 mg·kg-1） and LPS+NAR（100 mg·kg-1）.Rats were received a single LPS unilateral injection into the SN pars compacts,after seven daily intragastric administration of NAR,rats′ behavior was analyzed by rotarod test.Then,the expression of TH,IBA-1 and NLRP3 inflammasome were analyzed by Western blotting and immunofluorescence.In vitro experiments,BV-2 cel s were treated with different doses of NAR,and 1 h later,LPS(1 g·L;) was added to the medium for 24 h,then collect the culture medium and protein for later experiments.The production of IL-1β and IL-18 in culture medium were tested by ELISA,and the production of NO was detected by Griess reagent.The expression of IBA-1,NLRP3 and p-caspase 1 were detected by Western blotting.MN9 D cells were co-cultured with BV2 cells to mimic the animal experiments.MTT assay was used to analyzed the viability of MN9 D cells,and the expression of TH was detected by Western blotting.RESULTS NAR（100 mg · kg-1） could significantly improve the time of rats on the rotating（116.73 s vs 185.45 s,P<0.05）.The result of the pathological analysis also suggested that NAR could decrease the activation of microglia as well as the expression of NLRP3 Inflammasome.In addition,NAR also could suppress the expression of pro-inflammatory factor levels,such as IL-1β（P<0.05）,IL-18（P<0.05）,and the protection of NAR could be inhibited by siR NA NLRP3.Moreover,an in vitro co-culture system with BV2 and MN9 D cells wasused to find the protection of NAR must via microglia,while there is no effect of NAR were directly added to MN9 D cells.CONCLUSION NAR protection of LPS-induced dopaminergic neurons damage might be through mediating NLRP3 inflammasome.