Takeyama Y, Kamimura S, Kuroiwa A, Sohda T, Irie M, Shijo H, Okumura M
First Department of Internal Medicine, School of Medicine, Fukuoka University, Japan.
Alcohol Clin Exp Res. 1996 Dec;20(9 Suppl):335A-339A.
The pathophysiology of alcoholic liver disease (ALD) remains largely unknown. In this work, we have developed an experimental rat model to elucidate the mechanism of liver injury, including ALD, in which Kupffer cell-derived reactive oxygen intermediates (ROIs) might be involved. Groups of male Wistar rats were pair-fed on a liquid high-fat diet containing ethanol (36% of total calories) or isocaloric carbohydrate with or without dietary carbonyl iron (0.5% w/v) for 3 weeks. In this rat model, we investigated Kupffer cell-derived ROI generation, which affected hepatocellular injury and hepatic fibrosis in ALD. The production of ROIs in Kupffer cells isolated from the iron-fed, the ethanol-fed, and the ethanol plus iron-fed rats were significantly increased, compared with that in Kupffer cells isolated from control rats (iron > ethanol+iron > ethanol > > control). However, hepatic vitamin E content in the ethanol plus iron-fed rats was decreased rather than that in the iron-fed rats. Then, lipid peroxidation of isolated microsomes was assessed as malondialdehyde equivalents determined by thiobarbituric acid assay. Compared with controls, the malondialdehyde equivalents were elevated in experimental groups (ethanol+iron > ethanol > iron > control). Serum ALT levels were greatly elevated in rats fed a diet containing both ethanol and iron (ethanol+iron > iron > ethanol > control). Hepatic content of hydroxyproline was significantly increased in ethanol plus iron-fed rats, compared with rats other than the ethanol plus iron-fed group (ethanol+iron > iron > ethanol > control). These results suggested that the enhanced Kupffer cell-derived ROI generation could itself contribute to the increased susceptibility to lipid peroxidation, which might cause hepatocellular injury and lead to hepatic fibrosis in ALD.
酒精性肝病（ALD）的病理生理学在很大程度上仍然未知。在这项研究中，我们建立了一种实验性大鼠模型，以阐明包括ALD在内的肝损伤机制，其中库普弗细胞衍生的活性氧中间体（ROIs）可能参与其中。将雄性Wistar大鼠分组，以含乙醇（占总热量的36%）的液体高脂饮食或等热量碳水化合物饮食进行配对喂养，饮食中添加或不添加羰基铁（0.5% w/v），持续3周。在这个大鼠模型中，我们研究了库普弗细胞衍生的ROI生成，其影响ALD中的肝细胞损伤和肝纤维化。与从对照大鼠分离的库普弗细胞相比，从铁喂养、乙醇喂养和乙醇加铁喂养的大鼠分离的库普弗细胞中ROIs的产生显著增加（铁>乙醇+铁>乙醇>>对照）。然而，乙醇加铁喂养的大鼠肝脏维生素E含量比铁喂养的大鼠降低。然后，通过硫代巴比妥酸测定法测定丙二醛当量来评估分离微粒体的脂质过氧化。与对照组相比，实验组丙二醛当量升高（乙醇+铁>乙醇>铁>对照）。同时摄入乙醇和铁的大鼠血清ALT水平大幅升高（乙醇+铁>铁>乙醇>对照）。与乙醇加铁喂养组以外的大鼠相比，乙醇加铁喂养的大鼠肝脏羟脯氨酸含量显著增加（乙醇+铁>铁>乙醇>对照）。这些结果表明，库普弗细胞衍生的ROI生成增强本身可能导致脂质过氧化易感性增加，这可能导致ALD中的肝细胞损伤并导致肝纤维化。
