简介：Interleukin-6(IL-6)-deficientmicearepronetoethanol-inducedapoptosisandsteatosisintheliver;however,theunderlyingmechanismisnotfullyunderstood.Mitochondrialdysfunctioncausedbyoxidativestressisanearlyeventthatplaysanimportantroleinthepathogenesisofalcoholicliverdisease.Therefore,wehypothesizethattheprotectiveroleofIL-6inethanol-inducedliverinjuryismediatedviasuppressionofethanol-inducedoxidativestressandmitochondrialdysfunction.Totestthishypothesis,weexaminedtheeffectsofIL-6onethanol-inducedoxidativestress,mitochondrialinjury,andenergydepletionintheliversofIL-6(-/-)miceandhepatocytesfromethanol-fedrats.Ethanolconsumptionleadstostrongerinductionofmalondialdehyde(MDA)inIL-6(-/-)micecomparedtowild-typecontrolmice,whichcanbecorrectedbyadministrationofIL-6.Invitro,IL-6treatmentpreventsethanol-mediatedinductionofreactiveoxygenspecies(ROS),MDA,mitochondrialpermeabilitytransition(MPT),andethanol-mediateddepletionofadenosinetriphosphate(ATP)inhepatocytesfromethanol-fedrats.AdministrationofIL-6invivoalsoreversesethanol-inducedMDAandATPdepletioninhepatocytes.Finally,IL-6treatmentinducesmetallothioneinproteinexpression,butnotsuperoxidedismutaseandglutathioneperoxidaseinculturedhepatocytes.Inconclusion,IL-6protectsagainstethanol-inducedoxidativestressandmitochondrialdysfunctioninhepatocytesviainductionofmetallothioneinproteinexpression,whichmayaccountfortheprotectiveroleofIL-6inalcoholicliverdisease.