Refaai M A, Nguyen P N, Cluette-Brown J E, Laposata M
Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
Lipids. 2003 Mar;38(3):269-73. doi: 10.1007/s11745-003-1060-6.
The role of fatty acid ethyl esters (FAEE), the nonoxidative ethanol metabolites, as mediators of alcohol-induced organ damage is increasingly being recognized. FAEE are detectable in the blood and in liver and adipose tissue after ethanol ingestion, and on that basis, FAEE can be used as markers of ethanol intake. In this study, 10 samples of human brain were collected at autopsy at the Massachusetts Medical Examiner's Office and analyzed for FAEE. FAEE were isolated and quantified as mass per gram of wet weight. The blood ethanol level was also obtained in each case along with the other drugs detected in routine postmortem toxicology screening tests. Ethyl arachidonate was the predominant FAEE species in the brain, representing up to 77.4% of total FAEE in the brain. The percent age of ethyl arachidonate of the total FAEE in the brain was significantly higher than what has been found in all other organs and tissues previously analyzed. Linoleate, the precursor of arachidonate, was a poor substrate for FAEE synthesis, as the percentage of ethyl linoleate of the total FAEE content was extremely low. Thus, this reflects preferred incorporation of arachidonate into newly synthesized FAEE in the brain. Since arachidonate is derived from linoleate, which is depleted in FAEE while arachidonate is enriched, the synthesis of FAEE may be linked to the desaturation and elongation of linoleate to arachidonate.
脂肪酸乙酯(FAEE)作为酒精诱导器官损伤的介质,其作用越来越受到人们的认可,FAEE是乙醇的非氧化代谢产物。乙醇摄入后,可在血液、肝脏和脂肪组织中检测到FAEE,基于此,FAEE可作为乙醇摄入量的标志物。在本研究中,从马萨诸塞州法医办公室尸检时收集了10份人脑样本,并对其进行了FAEE分析。FAEE被分离出来,并以每克湿重的质量进行定量。同时还获取了每个案例的血液乙醇水平以及常规尸检毒理学筛查测试中检测到的其他药物。花生四烯酸乙酯是大脑中主要的FAEE种类,占大脑中总FAEE的77.4%。大脑中花生四烯酸乙酯占总FAEE的百分比显著高于之前分析过的所有其他器官和组织中的比例。花生四烯酸的前体亚油酸是FAEE合成的不良底物,因为亚油酸乙酯占总FAEE含量的百分比极低。因此,这反映了花生四烯酸优先掺入大脑中新合成的FAEE中。由于花生四烯酸来源于亚油酸,在FAEE中,亚油酸减少而花生四烯酸增加,FAEE的合成可能与亚油酸去饱和和延长生成花生四烯酸有关。