ImpairedautophagicfluxisassociatedwithincreasedendoplasmicreticulumstressduringthedevelopmentofNAFLDA´Gonza´lez-Rodrı´guez,RMayoral,etal.CellDeathandDiseaseLisa2014.7.31脂肪肝是指由于各种原因引起的肝细胞内脂肪堆积过多的临床病理综合症,是全身性疾病在肝脏的一种病理改变,相关综合症包括:代谢综合症,胰岛素抵抗综合症,肥胖综合症等。Introduction食物中脂肪供应过多血浆游离脂肪酸过多肝内脂肪酸利用减少肝内甘油三脂合成能力增强极低密度脂蛋白合成及分泌障碍脂蛋白代谢酶表达异常甘油三脂在肝细胞内沉积肝细胞脂肪变性Introduction脂肪肝分类根据脂肪变性累及范围弥漫性脂肪肝(急性和慢性)局灶性脂肪肝弥漫性脂肪肝伴正常肝岛根据病因酒精性脂肪肝(alcoholicliverdisease,ALD)非酒精性脂肪肝(non-alcoholicfattyliverdisease,NAFLD)非酒精性脂肪肝病(NAFLD)是指除外酒精和其他明确的损肝因素所致的肝细胞内脂肪过度沉积为主要特征的临床病理综合征,与胰岛素抵抗和遗传易感性密切相关的获得性代谢应激性肝损伤。IntroductionNAFLD病变过程Introduction自噬(autophagy)是细胞在饥饿、能量缺乏等代谢应激状态下的一种分解代谢过程。细胞可以通过自噬消除,降解受损、衰老和失去功能的细胞、细胞器及变性的蛋白等大分子,为细胞提供循环能量。自噬作用的大大增强,表现为胞质中迅速涌现大量自噬体,这一现象被称为“自噬潮”(autophagicflux),自噬潮为细胞提供度过危机的能量。肝细胞内有丰富的内质网,它是蛋白质合成、折叠、运输以及储存钙的主要场所,对各种刺激极为敏感,当功能紊乱时出现错误折叠与未折叠蛋白在腔内聚集以及细胞内钙平衡紊乱的状态,称为内质网应激(endoplasmicreticulumstress,ERS)。MethodsResultsTable1.Demographic,metabolic,biochemicalandhistopathologicalcharacteristicsofpatientswithnormalliverandNAFLDResultsFigure1.HepaticautophagyfluxisimpairedinNASandNASHpatients.ResultsFigure2.IncreasedERstresscorrelateswithaccumulationofp62andLC3-IIinliversofHFD-fedmice.ResultsFigure3.IncreasedERstresscorrelateswithaccumulationofp62andLC3-IIinliversofMCDdiet-fedmice.ResultsFigure4Short-termtreatmentwithPAinducesautophagyinhumanHuh7cells.ResultsFigure5RapamycinrecoverstheautophagicfluxafterprolongedtreatmentwithPAinhumanHuh7cellsandhumanprimaryhepatocytes.ResultsFigure6.RapamycindecreasescelldeathafterprolongedtreatmentwithPAinhumanHuh7cells.ResultsFigure7.EfectofsilencingofCHOPontheautophagicfluxandcelldeathafterprolongedtreatmentwithPAinhumanHuh7cells.ConclusionOurresultsdemonstratedthattheautophagicfluxisimpairedintheliverfrombothNAFLDpatientsandmurinemodelsofNAFLD,aswellasinlipid-overloadedhumanhepatocytes,anditcouldbeduetoelevatedERstressleadingtoapoptosis.Consequently,therapiesaimedtorestoretheautophagicfluxmightattenuateorpreventtheprogressionofNAFLD.Thankyou!