Cell culture model for acetaminophen-induced hepatocyte death in vivo
Cell culture model for acetaminophen-induced hepatocyte death in vivo
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DOI：
10.1016/s0006-2952(02)01180-2
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发表时间：
2002-08-01
影响因子：
5.8
通讯作者：
Bruschi, SA
中科院分区：
文献类型：
--
作者：
Pierce, RH;Franklin, CC;Bruschi, SA
对乙酰氨基酚（N-乙酰基-对氨基苯酚，APAP，扑热息痛）是一种流行的、相对安全的镇痛药，过量使用可引起致命的小叶中心肝损伤。在分化的、转化生长因子α（TGF α）过表达的肝细胞系中研究了APAP诱导的细胞死亡，发现在与临床过量情况相关的浓度和时间范围内发生。在APAP诱导的细胞毒性过程中，协调的多细胞器崩溃是明显的，具有广泛的，但选择性的，体外蛋白质降解事件。细胞蛋白酶体活性抑制与APAP治疗，但不与相对非肝毒性APAP区域异构体，N-乙酰间氨基苯酚（AMAP）。低浓度的蛋白酶体定向抑制剂MG 132（N-carbobenzoxyl-Leu-Leu-Leucinal）增加染色质凝聚和细胞应激反应优先在AMAP处理的文化，这表明蛋白酶体的贡献APAP-而不是AMAP介导的细胞死亡。在形态学上观察到线粒体的APAP特异性改变，并有线粒体体外增殖的证据。在体内也发现了细胞蛋白水解事件的生化改变，包括APAP或AMAP介导的caspase-3加工抑制。这些结果表明，尽管保留了细胞凋亡的一些属性，但APAP和AMAP介导的细胞死亡具有与长期坏死一致的额外独特特征。
Overdose of the popular, and relatively safe, analgesic acetaminophen (N-acetyl-p-aminophenol, APAP, paracetamol) can produce a fatal centrilobular liver injury. APAP-induced cell death was investigated in a differentiated, transforming growth factor alpha (TGFalpha)-overexpressing, hepatocyte cell line and found to occur at concentrations, and over time frames, relevant to clinical overdose situations. Coordinated multiorganellar collapse was evident during APAP-induced cytotoxicity with widespread, yet selective, protein degradation events in vitro. Cellular proteasomal activity was inhibited with APAP treatment but not with the comparatively nonhepatotoxic APAP regioisomer, N-acetyl-m-aminophenol (AMAP). Low concentrations of the proteasome-directed inhibitor MG132 (N-carbobenzoxyl-Leu-Leu-Leucinal) increased chromatin condensation and cellular stress responses preferentially in AMAP-treated cultures, suggesting a contribution of the proteasome in APAP- but not AMAP-mediated cell death. APAP-specific alterations to mitochondria were observed morphologically with evidence of mitochondrial proliferation in vitro. Biochemical alterations to cellular proteolytic events were also found in vivo, including APAP- or AMAP-mediated inhibition of caspase-3 processing. These results indicate that, although retaining some attributes of apoptosis, both APAP- and AMAP-mediated cell death have additional distinctive features consistent with longer term necrosis.