简介：GinsenosideRg1（Rg1）hasanti-agingandanti-neurodegenerativeeffects.However,themechanismsunderlyingtheseactionsremainunclear.TheaimofthepresentstudywastodeterminewhetherRg1affectshippocampalsurvivalandneuriteoutgrowthinvitroafterexposuretoamyloid-betapeptidefragment25–35(Aβ25–35),andtoexplorewhethertheextracellularsignal-regulatedkinase（ERK）andAktsignalingpathwaysareinvolvedinthesebiologicalprocesses.Weculturedhippocampalneuronsfromnewbornratsfor24hours,thenaddedRg1tothemediumforanother24hours,withorwithoutpharmacologicalinhibitorsofthemitogen-activatedproteinkinase（MAPK）familyorAktsignalingpathwaysforafurther24hours.Wethenimmunostainedtheneuronsforgrowthassociatedprotein-43,andmeasuredneuritelength.Inaseparateexperiment,weexposedculturedhippocampalneuronstoAβ25–35for30minutes,beforeaddingRg1for48hours,withorwithoutAktorMAPKinhibitors,andassessedneuronalsurvivalusingHoechst33258staining,andphosphorylationofERK1/2andAktbywesternblotanalysis.Rg1inducedneuriteoutgrowth,andthiseffectwasblockedbyAPI-2（Aktinhibitor）andPD98059（MAPK/ERKkinaseinhibitor）,butnotbySP600125orSB203580（inhibitorsofc-JunN-terminalkinaseandp38MAPK,respectively）.Consistentwiththiseffect,Rg1upregulatedthephosphorylationofAktandERK1/2;theseeffectswerereversedbyAPI-2andPD98059,respectively.Inaddition,Rg1significantlyreversedAβ25–35-inducedapoptosis;thiseffectwasblockedbyAPI-2andPD98059,butnotbySP600125orSB203580.Finally,Rg1significantlyreversedtheAβ25–35-induceddecreaseinAktandERK1/2phosphorylation,butAPI-2preventedthisreversal.OurresultsindicatethatRg1enhancesneuriteoutgrowthandprotectsagainstAβ25–35-induceddamage,andthatitsmechanismmayinvolvetheactivationofAktandERK1/2signaling.更多还原