简介：Overthepastfewdecades,non-alcoholicfattyliverdisease(NAFLD)hasbecomeone,ifnotthemostcommon,causeofchronicliverdiseaseaffectingbothadultsandchildren.Theincreasingnumberofcasesatanearlyageisthemostworryingaspectofthispathology,sinceitprovidesmoretimeforitsevolution.Thespectrumofthisdiseaserangesfromliversteatosistosteatohepatitis,fibrosisandinsomecases,hepatocellularcarcinoma.NAFLDmaynotalwaysbeconsideredabenigndiseaseandhepatologistsmustbecautiousinthepresenceoffattyliver.Thisshouldprompttheuseoftheavailableexperimentalmodelstounderstandbetterthepathogenesisandtodeveloparationaltreatmentofadiseasethatisdangerouslyincreasing.Inspiteofthegrowingefforts,thepathogenesisofNAFLDisstillpoorlyunderstood.InthepresentarticlewereviewthemostrelevanthypothesesandevidencethataccountfortheprogressionofNAFLDtonon-alcoholicsteatohepatitis(NASH)andfibrosis.TheavailableinvitroandinvivoexperimentalmodelsofNASHarediscussedandrevisedintermsoftheirvalidityintranslationalstudies.Thesestudiesmustbeaimedatthediscoveryofthestillunknowntriggersormediatorsthatinducetheprogressionofhepaticinflammation,apoptosisandfibrosis.