Effect Of Methylprednisolone On Neurobrucellosis Based On NF-κB Signaling Pathway

Objective:In this research,methylprednisolone was used to intervene microglia infected by Brucella glabrata S2308,and the contents of inflammatory factors IL-6,IL-8,TNF-αand the transcription level of NF-κB were detected to explore the alleviation effect and potential mechanism of methylprednisolone on the inflammatory response of neurobrucellosis.Methods:This experiment was set up into 4 groups,each with 3 replicates,and the human microglia HMC3 cells were randomly divided into blank group,immersion group and two drug groups.The blank group was added with an equal amount of sterile distilled water,the immersion group was added with Brucella glabrata S2308and the same amount of sterile distilled water,and two drug groups were added with Brucella glabrata S2308 and different concentrations of methylprednisolone respectively(Based on literature reports,we chose 10^-8mmol/L and 10^-6mmol/L as the drug concentrations for the experiments).The inflammatory cytokines IL-6,TNF-αand IL-8 were investigated by ELISA.The RT-q PCR was utilized to investigate m RNA of IL-6,TNF-α,IL-8 and NF-κB.The measurement data were expressed as（?X±S）.SPSS 24.0 was used for statistical analysis and t-test was used to compare the two sets of data that obeyed the normal distribution.The test level wasα=0.05.When P<0.05,the discrepancy was statistical implication.Results:（1）Contrast of the blank group and the immersion group,the inflammatory factors such as IL-6,TNF-αand IL-8 in the immersion group increased,indicating that the discrepancy was significant（P<0.05）.Compared to the immersion group,the inflammatory factors such as IL-6,IL-8 and TNF-αin the drug group(methylprednisolone 10^-8mmol/L,10^-6mmol/L)were decreased,and the discrepancy was significant（P<0.05）.Compared with methylprednisolone(10^-8mmol/L)group,the contents discrepancy of TNF-αin methylprednisolone(10^-6mmol/L)group was decreased and the discrepancy was significant（P<0.05）,the difference of IL-6,IL-8was no meaningful（P>0.05）.（2）Compared with the blank group,the m RNA expressions of IL-6,IL-8,TNF-αand NF-κB in the immersion group were increased,and the difference was significant（P<0.05）.Compared with the immersion group,the m RNA expressions of IL-6,IL-8,TNF-αand NF-κB in the drug group(methylprednisolone 10^-8mmol/L,10^-6mmol/L)were decreased,and the difference was significant（P<0.05）.Compared with the methylprednisolone(10^-8mmol/L)group,the the m RNA expressions of IL-6,IL-8 and TNF-αin the methylprednisolone(10^-6mmol/L)group were decreased,and the difference was meaningful（P<0.05）,but NF-κB m RNA content discrepancy was no significant（P>0.05）.Conclusion:Methylprednisolone can regulate the expression of NF-κB in Brucella-infected microglia and reduce the inflammatory cytokines IL-6,IL-8 and TNF-αin microglia infected by Brucella.It is concluded that methylprednisolone play a neuroprotective role by inhibiting the NF-κB signal passage,cutting down the expression of IL-6,IL-8 and TNF-α.