AIM:Tostudytheformationofintracellularglyceraldehyde-derivedadvancedglycationendproducts(Glycer-AGEs)inthepresenceofhighconcentrationsoffructose.METHODS:CellsofthehumanhepatocytecelllineHep3Bwereincubatedwithorwithoutfructoseforfivedays,andthecorrespondingcelllysateswereseparatedbytwo-dimensionalgradientsodiumdodecylsulfate-polyacrylamidegelelectrophoresis.Glycer-AGEsweredetectedwiththeanti-Glycer-AGEsantibody.Furthermore,theidentificationoftheproteinsthataremodifiedbyglyceraldehydeinthepresenceofhighconcentrationsoffructosewasconductedusingmatrixassistedlaserdesorption/ionizationtime-of-flightmassspectrometry(MALDI-TOF-MS).TheproteinandmRNAlevelsweredeterminedbyWesternblottingandrealtimereversetranscriptionPCR,respectively.RESULTS:Theresultsofthetwo-dimensionalgradientsodiumdodecylsulfate-polyacrylamidegelelectrophoresisindicatedagreateramountofGlycerAGEsinthesampleexposedtohighconcentrationsoffructosethaninthecontrol.ThedetectedGlycerAGEsshowedisoelectricpointsintherangeof8.0-9.0andmolecularweightsintherangeof60-80kDa.TheheterogeneousnuclearribonucleoproteinM(hnRNPM),whichplaysanimportantroleinregulatinggeneexpressionbyprocessingheterogeneousnuclearRNAstoformmaturemRNAs,wasidentifiedasamodifiedproteinusingMALDI-TOF-MS.Increasingtheconcentrationoffructoseinthemediuminducedaconcentration-dependentincreaseinthegeneratedGlycer-AGEs.Furthermore,inanexperimentusingglyceraldehyde,whichisaprecursorofGlycer-AGEs,hnRNPMwasfoundtobemoreeasilyglycatedthantheotherproteins.CONCLUSION:Theresultssuggestthatglyceraldehyde-modifiedhnRNPMaltersgeneexpression.Thischangemaycauseadverseeffectsinhepatocytesandmayserveasatargetfortherapeuticintervention.
