Effect Of ICS ? On Inflammatory Response Of Astrocytes Induced By Lipopolysaccharide

Objective:To study the effect of ICS ? on lipopolysaccharide(LPS)-induced astrocytes inflammatory response and explore its possible mechanismMethods:Primary astrocytes were isolated from cerebral cortex of neonatal SD rats and cultured.Astrocytes were divided into blank group,blank + ICS ? high concentration group(20 ?M ICS ?),model group(1 ?g/mL LPS),model +ICS ? low concentration group(1 ?g/mL LPS + 5 ?M ICS)?),model + ICS ? medium concentration group(1?g/mL LPS+10 ?M ICS ?),model+ICS ? high concentration group(1?g/mL LPS+20 ?M ICS ?),model+dexamethasone group(1 ?g/mL LPS+1 ?M DXMS).Astrocytes were pretreated with ICS ?(5,10,20 ?M)or dexamethasone(1 ?M)for 1 h,then LPS was used to establish a model of inflammation in vitro,and IC.S ? or DXMS was added for another 24 h.MTT assay was used to detect the safe concentration range of ICS ? in astrocyte,and the effect of ICS ? on LPS-induced astrocyte inflammation was observed after determination of the safe concentrations.Enzyme-linked immunosorbent assay was used to detect the levels of TNF-?,IL-?,A?1-40 and A?1-42 in astrocyte.Detection of nitric oxide levels in astrocytes using Griess method.Western Blot was used to detect the protein expression of COX-2,iNOS,1?B-?,NF-?B(p65)(nucleus),NF-?B(p65)(cytoplasm),BACE1 and APP,as well as the phosphorylation levels of NF-?B(p65),IKK-? and IKK-?Furthermore,molecular docking was used to evaluated the relationship between ICS ? and BACE1Results:0-50 ?M ICS ? did not exert toxic effects in astrocytes.The levels of TNF-a,IL-1? and NO were significantly increase in the astrocytes than those of the blank group after LPS insults(P<0.05).Moreover,LPS markedly increased COX-2,iNOS,NF-?B(nucleus),BACE1 and APP protein expressions(P<0.05)and significantly decreased I?B-?,NF-?B(cytoplasm)expressions(P<0.05);while,the phosphorylation levels of NF-?B(p65),IKK-? and IKK-? were increased by LPS(P<0.05).However,ICS ?significantly reduced TNF-?,IL-1? and NO levels(P<0.05).ICS ? also down-regulated the COX-2,iNOS,NF-KB(nucleus)expression(P<0.05).Moreover,ICS ? not only up-regulated NF-?B(cytoplasmic)and I?B-? expressions(P<0.05),but also down-regulated phosphorylation levels of NF-?B(p65),IKK-? and IKK-?(P<0.05)Conclusion:In this study,ICS ? exerts neuroprotective effects on LPS-induced inflammation in astrocytes,through regulating IKK/I?B/NF-?B/BACE1 signaling pathway.