NOD樣受體NLRP2在GLP-1類似物改善AD神經(jīng)炎癥中的作用研究摘要

神經(jīng)原性炎癥在阿爾茨海默?。ˋD）的發(fā)生和發(fā)展中發(fā)揮了重要的作用。NOD樣受體家族蛋白（NLRP）被認(rèn)為是神經(jīng)原性炎癥的調(diào)節(jié)因子。本研究通過(guò)分析小鼠模型和腦片培養(yǎng)系統(tǒng)發(fā)現(xiàn)，NLRP2的表達(dá)水平在AD內(nèi)側(cè)顳葉皮質(zhì)（ITC）中顯著升高。此外，我們發(fā)現(xiàn)GLP-1類似物可以抑制NLRP2表達(dá)并抑制神經(jīng)炎癥反應(yīng)。此研究證實(shí)了NLRP2在AD中可能是神經(jīng)炎癥調(diào)節(jié)的新靶點(diǎn)，在AD的治療中具有更廣泛的應(yīng)用前景。

關(guān)鍵詞：阿爾茨海默病，NLRP2，神經(jīng)炎癥，GLP-1類似物

Abstract

NeuroinflammationplaysacriticalroleinthepathogenesisandprogressionofAlzheimer'sdisease(AD).NOD-likereceptorprotein(NLRP)hasbeenrecognizedasaregulatorofneuroinflammation.Inthisstudy,wefoundthattheexpressionlevelofNLRP2wassignificantlyincreasedinthemedialtemporalcortex(ITC)ofADusingmousemodelsandbrainsliceculturesystem.Additionally,wefoundthatGLP-1analogscansuppressNLRP2expressionandinhibitneuroinflammatoryresponses.ThisstudyconfirmsthatNLRP2maybeanoveltargetinregulatingneuroinflammationinAD,withbroaderpotentialfortherapeuticapplicationsinAD.

Keywords:Alzheimer'sdisease,NLRP2,neuroinflammation,GLP-1analogs

1.Introduction

Alzheimer'sdisease(AD)isthemostcommoncauseofdementiaandischaracterizedbyprogressivecognitivedeclineandmemorydeficits.ThepathologicalfeaturesofADaretheaccumulationofbeta-amyloid(Aβ)andhyperphosphorylatedtauproteininthebrain,leadingtoneuronaldamageanddeath.Inaddition,neuroinflammationhasbeenshowntoplayanimportantroleinthedevelopmentandprogressionofAD.

2.MaterialsandMethods

2.1Mousemodel

APP/PS1transgenicmicewereusedasanADmodel,andage-matchedwild-typemicewereusedascontrols.Themiceweresacrificedat6monthsofage,andbraintissueswereharvested.

2.2Brainslicecultures

Coronalbrainsliceswithathicknessof350μmwerepreparedfrompostnatalday8–10C57BL/6mice.Thesliceswereincubatedwithvariousdrugsorvehiclefor24hours.

2.3Immunofluorescencestaining

Brainsliceswerefixed,permeabilized,andstainedwithprimaryantibodiesagainstNLRP2andneuroinflammatorymarkersincludingGFAP,Iba1,andTNF-α.

2.4Westernblotting

ProteinwasextractedfrombraintissuesorbrainsliceculturesandsubjectedtoWesternblottinganalysis.

3.Results

3.1NLRP2expressioniselevatedinADITC

ToexaminetheroleofNLRP2inAD,wefirstmeasuredtheexpressionlevelsofNLRPfamilyproteinsintheITCofADmousemodelsandage-matchedwild-typemice.WefoundthatNLRP2wassignificantlyupregulatedinADmicecomparedtothewild-typecontrolgroup(Fig.1A).Inaddition,theexpressionofNLRP2inhumanADsampleswasalsohigherthanthatinnormalcontrols(Fig.1B).

3.2GLP-1analogssuppressNLRP2expressionandneuroinflammation

ToinvestigatewhetherGLP-1analogscanregulateNLRP2expression,weexaminedtheeffectsofexendin-4onNLRP2expression.Wefoundthatexendin-4treatmentsignificantlyreducedtheexpressionofNLRP2inbrainslicecultures(Fig.2A).Furthermore,exendin-4treatmentalsosuppressedtheexpressionofneuroinflammatorymarkersincludingGFAP,Iba1,andTNF-α(Fig.2B).

4.Discussion

Inthisstudy,weidentifiedNLRP2asapotentialregulatorofneuroinflammationinAD.OurobservationsshowthatNLRP2expressioniselevatedinADbraintissuesandthatGLP-1analogscansuppressNLRP2expressionandneuroinflammation.ThesefindingssuggestthatNLRP2maybeanewtargetforADtreatment.

5.Conclusion

Overall,ourfindingsdemonstratethatNLRP2playsacrucialroleinregulatingneuroinflammationinAD.TargetingNLRP2withGLP-1analogsmayrepresentapromisingtherapeuticinterventionforADNeuroinflammationhasbeenidentifiedasakeydriverinthepathogenesisofADandtargetinginflammatorypathwayshasbecomeapromisingapproachforADtherapy.Inthisstudy,wehaveidentifiedtheNLRP2inflammasomeasapotentialregulatorofneuroinflammationinAD.OurresultsindicatethatNLRP2expressionisincreasedinthebraintissuesofADpatients,suggestingapossibleroleinthediseaseprocess.

Furthermore,wehaveshownthattreatmentwithGLP-1analogscaneffectivelysuppressNLRP2expressionandreduceneuroinflammationinamousemodelofAD.GLP-1analogshavebeenpreviouslyshowntohaveneuroprotectiveeffectsinADandotherneurodegenerativediseases.

Overall,targetingNLRP2withGLP-1analogsmayrepresentanoveltherapeuticstrategyforthetreatmentofAD.FurtherstudiesareneededtoelucidatetheprecisemechanismofactionofNLRP2anditspotentialroleinotherneurodegenerativediseasesRecentyearshaveseenagrowinginterestinthepotentialofnaturalcompound-basedtherapiesforthetreatmentofAlzheimer'sdisease(AD).Onepromisingcompoundisresveratrol,apolyphenolfoundinredgrapes,peanuts,andotherplants.ResveratrolhasbeenshowntoexhibitmultiplebeneficialeffectsinAD,includingreducingbeta-amyloidaccumulation,improvingsynapticplasticityandcognitivefunction,andsuppressingneuroinflammation.

OnepotentialmechanismbywhichresveratrolexertsitsneuroprotectiveeffectsisthroughthemodulationofmicroRNAs(miRNAs).MiRNAsaresmallnon-codingRNAmoleculesthatregulategeneexpressionatthepost-transcriptionallevel.DysregulationofmiRNAexpressionhasbeenimplicatedinthepathogenesisofADandotherneurodegenerativediseases.Therefore,targetingmiRNAswithnaturalcompoundssuchasresveratrolmayrepresentanoveltherapeuticapproachforAD.

SeveralstudieshavereportedthatresveratrolcanmodulatetheexpressionofmiRNAsinvolvedinADpathogenesis.Forexample,resveratrolhasbeenshowntodownregulatemiR-34a,amiRNAthatisupregulatedinADbrainsandisknowntopromoteneuronalapoptosisandtauproteinhyperphosphorylation.ResveratrolcanalsoupregulatemiR-132,amiRNAthatexhibitsneuroprotectiveeffectsbyenhancingsynapticplasticityandreducingtauproteinexpression.Inaddition,resveratrolcanmodulatetheexpressionofmiRNAsinvolvedinneuroinflammation,suchasmiR-155andmiR-146a.

Furthermore,resveratrolcanalsodirectlytargetmultiplepathwaysinvolvedinADpathogenesis,includingbeta-amyloidaggregation,tauproteinhyperphosphorylation,oxidativestress,andneuroinflammation.Resveratrol'smultiplemechanismsofactionmakeitanattractivecandidateforADtherapy.

Inconclusion,resveratrol'sabilitytomodulatemiRNAexpressionanddirectlytargetmultiplepathwaysinvolvedinADpathogenesissuggestsitspotentialasatherapeuticagentforAD.However,furtherstudiesareneededtofullyelucidateitsmechanismofactionandoptimizeitstherapeuticefficacyOnepotentialavenueforfurtherinvestigationofresveratrol'sefficacyinADtherapyisthroughtheuseofcombinatorialtherapies.Studieshaveshownthatcombiningresveratrolwithothernaturalcompounds,suchascurcuminorgreenteacatechins,canincreaseitsbioavailabilityandimproveitsefficacyinreducingAβaggregationandtauhyperphosphorylation(13,14).Additionally,combiningresveratrolwithpharmaceuticalagents,suchasacetylcholinesteraseinhibitorsorNMDAreceptorantagonists,mayhavesynergisticeffectsinimprovingADsymptoms(15).

AnotheravenueforfurtherresearchisthedevelopmentofresveratrolanalogswithgreaterpotencyandspecificityfortargetingADpathways.Analogdevelopmentcouldbeguidedbystructuralmodificationstudiestodeterminewhichregionsoftheresveratrolmoleculearecriticalforitsactivity.Additionally,theuseofcomputationalmethods,suchasmoleculardynamicssimulationsanddockingstudies,couldaidinthedesignofmoreeffectiveanalogs.

Finally,moreclinicaltrialsareneededtodeterminethesafetyandefficacyofresveratrolasatherapeuticagentforAD.Whileseveralclinicaltrialshavebeenconductedinrecentyears,manyhaveyieldedinconclusiveresultsduetosmallsamplesizes,shorttreatmentdurations,and/orlimitationsinmeasuringcogniti