Kanbagli Oznur, Balkan Jale, Aykaç-Toker Gülçin, Uysal Müjdat
Department of Biochemistry, Istanbul Medical Faculty, University of Istanbul, Istanbul,Turkey.
Biol Pharm Bull. 2002 Nov;25(11):1482-4. doi: 10.1248/bpb.25.1482.
In this study, prooxidant and antioxidant status in liver homogenates and their mitochondrial fractions were investigated in both chronic and chronic plus acute ethanol-treated rats. Increases in serum transaminase activities, as well as increases in total lipid, triglyceride, malondialdehyde (MDA) and diene conjugate (DC) levels and decreases in glutathione (GSH), vitamin E and vitamin C levels, have been observed in liver homogenates following chronic ethanol treatment (20% ethanol, v/v as drinking water for 3 months), but CuZn-superoxide dismutase (CuZnSOD), glutathione peroxidase (GSH-Px) and glutathione transferase (GST) activities remained unchanged in postmitochondrial fractions. When an acute dose of ethanol (5 g/kg, i.p.) was given rats which had received ethanol chronically, serum transaminase activities and hepatic lipid and MDA and DC levels increased further, but GSH levels and antioxidant enzymes decreased more compared to the chronic ethanol-treated rats. There were no significant differences in the levels of MDA, DC and protein carbonyl and the activities of GSH-Px and GST in the hepatic mitochondrial fraction of rats following both chronic and chronic plus acute treatments. Mn-superoxide dismutase (MnSOD) activities increased in both groups, but mitochondrial GSH levels decreased only after chronic plus acute treatment. Therefore, we suggest that the increase in MnSOD activity may play an important role in the regulation of mitochondrial susceptibility against ethanol-induced oxidative stress.
在本研究中，我们对慢性乙醇处理的大鼠以及慢性加急性乙醇处理的大鼠的肝脏匀浆及其线粒体部分中的促氧化剂和抗氧化剂状态进行了研究。慢性乙醇处理（20%乙醇，v/v，作为饮用水饮用3个月）后，肝脏匀浆中血清转氨酶活性升高，总脂质、甘油三酯、丙二醛（MDA）和二烯共轭物（DC）水平升高，谷胱甘肽（GSH）、维生素E和维生素C水平降低，但线粒体后部分中的铜锌超氧化物歧化酶（CuZnSOD）、谷胱甘肽过氧化物酶（GSH-Px）和谷胱甘肽转移酶（GST）活性保持不变。当给长期接受乙醇处理的大鼠腹腔注射急性剂量的乙醇（5 g/kg）时，血清转氨酶活性以及肝脏脂质、MDA和DC水平进一步升高，但与慢性乙醇处理的大鼠相比，GSH水平和抗氧化酶下降得更多。在慢性处理和慢性加急性处理的大鼠肝脏线粒体部分中，MDA、DC和蛋白质羰基水平以及GSH-Px和GST活性没有显著差异。两组的锰超氧化物歧化酶（MnSOD）活性均升高，但仅在慢性加急性处理后线粒体GSH水平降低。因此，我们认为MnSOD活性的增加可能在调节线粒体对乙醇诱导的氧化应激的易感性中起重要作用。
