Yin M, Ikejima K, Arteel G E, Seabra V, Bradford B U, Kono H, Rusyn I, Thurman R G
Laboratory of Hepatobiology and Toxicology, Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7365, USA.
J Pharmacol Exp Ther. 1998 Aug;286(2):1014-9.
Glycine prevents hepatic damage caused by hypoxia-reoxygenation, diminishes mortality due to endotoxin and minimizes alcoholic liver injury by decreasing blood ethanol. Our purpose was to investigate the effect of dietary glycine during recovery from early alcohol-induced injury, using a model that mimics the clinical presentation and histopathology with alcoholics. Male Wistar rats were exposed to ethanol continuously for 6 wk via intragastric feeding that resulted in typical histology of alcoholic liver injury, including steatosis, inflammation, necrosis and increased serum levels of aspartate aminotransferase and alanine aminotransferase. After cessation of ethanol, one group of rats received a control diet, the other a glycine-containing diet for 2 wk. During this period, all parameters studied tended to return to baseline values. However, serum aspartate aminotransferase and alanine aminotransferase recovered about 30% more rapidly in rats fed glycine. Further, the hepatic pathology score was also significantly lower in the glycine group than in controls (0.5 vs. 2.6). After 1 wk, steatosis was reduced significantly more in the glycine group (5. 6%) than in controls (8.9%). Glycine also diminished numbers of infiltrating leukocytes and necrotic cells significantly more than in controls. This beneficial effect of glycine may be partly explained by the fact that glycine increased influx of chloride into Kupffer cells leading to diminished tumor necrosis factor-alpha production. These results indicate that a glycine containing diet expedites the process of recovery from ethanol-induced liver injury and may lead to its clinical application in alcoholic hepatitis.
甘氨酸可预防缺氧-复氧引起的肝损伤,降低内毒素所致的死亡率,并通过降低血液中的乙醇含量将酒精性肝损伤降至最低。我们的目的是利用一种模拟酗酒者临床表现和组织病理学的模型,研究在早期酒精性损伤恢复过程中膳食甘氨酸的作用。雄性Wistar大鼠通过胃内喂养连续6周暴露于乙醇中,导致出现酒精性肝损伤的典型组织学表现,包括脂肪变性、炎症、坏死以及血清天冬氨酸氨基转移酶和丙氨酸氨基转移酶水平升高。停止给予乙醇后,一组大鼠给予对照饮食,另一组给予含甘氨酸的饮食,持续2周。在此期间,所有研究参数均趋于恢复至基线值。然而,喂食甘氨酸的大鼠血清天冬氨酸氨基转移酶和丙氨酸氨基转移酶的恢复速度比对照组快约30%。此外,甘氨酸组的肝脏病理学评分也显著低于对照组(0.5对2.6)。1周后,甘氨酸组的脂肪变性减少幅度(5.6%)明显大于对照组(8.9%)。甘氨酸还使浸润的白细胞和坏死细胞数量比对照组显著减少。甘氨酸的这种有益作用可能部分归因于甘氨酸增加了氯离子流入库普弗细胞,导致肿瘤坏死因子-α的产生减少。这些结果表明,含甘氨酸饮食可加速乙醇诱导的肝损伤的恢复过程,并可能使其在酒精性肝炎中得到临床应用。