Thurman R G, Bradford B U, Iimuro Y, Knecht K T, Arteel G E, Yin M, Connor H D, Wall C, Raleigh J A, Frankenberg M V, Adachi Y, Forman D T, Brenner D, Kadiiska M, Mason R P
Department of Pharmacology, The University of North Carolina at Chapel Hill, 27599-7365, USA.
J Gastroenterol Hepatol. 1998 Sep;13 Suppl:S39-50.
Previous research from this laboratory using a continuous enteral ethanol (EtOH) administration model demonstrated that Kupffer cells are pivotal in the development of EtOH-induced liver injury. When Kupffer cells were destroyed using gadolinium chloride (GdCl3) or the gut was sterilized with polymyxin B and neomycin, early inflammation due to EtOH was blocked. Anti-tumour necrosis factor (TNF)-alpha antibody markedly decreased EtOH-induced liver injury and increased TNF-mRNA. These findings led to the hypothesis that EtOH-induced liver injury involves increases in circulating endotoxin leading to activation of Kupffer cells. Pimonidazole, a nitro-imidazole marker, was used to detect hypoxia in downstream pericentral regions of the lobule. Following one large dose of EtOH or chronic enteral EtOH for 1 month, pimonidazole binding was increased significantly in pericentral regions of the liver lobule, which was diminished with GdCl3. Enteral EtOH increased free radical generation detected with electron spin resonance (ESR). These radical species had coupling constants matching alpha-hydroxyethyl radical and were shown conclusively to arise from EtOH based on a doubling of the ESR lines when 13C-EtOH was given. Alpha-hydroxyethyl radical production was also blocked by the destruction of Kupffer cells with GdCl3. It is known that females develop more severe EtOH-induced liver injury more rapidly and with less EtOH than males. Female rats on the enteral protocol exhibited more rapid injury and more widespread fatty changes over a larger portion of the liver lobule than males. Plasma endotoxin, ICAM-1, free radical adducts, infiltrating neutrophils and transcription factor NFkappaB were approximately two-fold greater in livers from females than males after 4 weeks of enteral EtOH treatment. Furthermore, oestrogen treatment increased the sensitivity of Kupffer cells to endotoxin. These data are consistent with the hypothesis that Kupffer cells participate in important gender differences in liver injury caused by ethanol.
该实验室先前使用持续肠内给予乙醇（EtOH）的模型进行的研究表明，库普弗细胞在乙醇诱导的肝损伤发展过程中起关键作用。当使用氯化钆（GdCl3）破坏库普弗细胞或用多粘菌素B和新霉素使肠道灭菌时，乙醇引起的早期炎症被阻断。抗肿瘤坏死因子（TNF）-α抗体显著降低了乙醇诱导的肝损伤并增加了TNF-mRNA。这些发现导致了这样一种假说，即乙醇诱导的肝损伤涉及循环内毒素增加，从而导致库普弗细胞活化。匹莫硝唑是一种硝基咪唑标记物，用于检测小叶中央周围下游区域的缺氧情况。给予一剂大剂量乙醇或进行1个月的慢性肠内乙醇给药后，肝小叶中央周围区域的匹莫硝唑结合显著增加，而GdCl3可使其减少。肠内给予乙醇会增加用电子自旋共振（ESR）检测到的自由基生成。这些自由基的耦合常数与α-羟乙基自由基匹配，并且当给予13C-乙醇时，ESR谱线加倍，从而确凿地表明这些自由基源自乙醇。用GdCl3破坏库普弗细胞也可阻断α-羟乙基自由基的产生。已知雌性比雄性更迅速且以更少的乙醇量发生更严重的乙醇诱导的肝损伤。接受肠内给药方案的雌性大鼠比雄性大鼠表现出更迅速的损伤以及在更大比例的肝小叶中出现更广泛的脂肪变化。肠内给予乙醇4周后，雌性大鼠肝脏中的血浆内毒素、细胞间黏附分子-1、自由基加合物、浸润的中性粒细胞和转录因子NFκB比雄性大鼠大约高两倍。此外，雌激素治疗增加了库普弗细胞对内毒素的敏感性。这些数据与库普弗细胞参与乙醇所致肝损伤中重要的性别差异这一假说一致。
