Ghrelin augments murine T‐cell proliferation by activation of the phosphatidylinositol‐3‐kinase, extracellular signal‐regulated kinase and protein kinase C signaling pathways

摘要

Thymicatrophyoccursduringnormalaging,andisacceleratedbyexposuretochronicstressorsthatelevateglucocorticoidlevelsandimpairthena?veTcelloutput.Theorexigenichormoneghrelinwasrecentlyshowntoattenuateage‐associatedthymicatrophy.Here,wereportthatghrelinenhancestheproliferationofmurineCD4+primaryTcellsandaCD4+T‐cellline.GhrelininducedactivationoftheERK1/2andAktsignalingpathways,viaupstreamactivationofphosphatidylinositol‐3‐kinaseandproteinkinaseC,toenhanceT‐cellproliferation.Moreover,ghrelininducedexpressionofthecellcycleproteinscyclinD1,cyclinE,cyclin‐dependentkinase2(CDK2)andretinoblastomaphosphorylation.Finally,ghrelinactivatedtheabove‐mentionedsignalingpathwaysandstimulatedthymocyteproliferationinyoungandoldermiceinvivo...