Ueshima Y, Matsuda Y, Tsutsumi M, Takada A
Department of Internal Medicine, Kanazawa Medical University, Ishikawa, Japan.
Alcohol Alcohol Suppl. 1993;1B:15-9. doi: 10.1093/alcalc/28.supplement_1b.15.
At least four types of aldehyde dehydrogenase (ALDH) isozymes exist in human liver: acetaldehyde (Ac-CHO) is metabolized mainly by ALDH2. However, the role of ALDH1 in Ac-CHO metabolism is not well known, because ALDH1 deficiency is rare. In the present study, changes in blood levels of Ac-CHO were analyzed in a person with ALDH1 deficiency who is also heterozygous for the ALDH2 alleles, and subjects with normal ALDH1, in order to clarify the roles of ALDH1 in the metabolism of Ac-CHO. By isoelectric focusing analysis of ALDH in red blood cells (RBC), the ALDH1 band was not detectable in a male subject, indicating ALDH1 deficiency. In this subject, ALDH1 activity was nearly null, but the activities in his wife and two children were normal. Serial changes of blood Ac-CHO levels following a small amount of ethanol were analyzed. The peak levels of Ac-CHO were not different between the subject with ALDH1 deficiency and the person with normal ALDH1. However, the decrease from the peak values of Ac-CHO was clearly slower in the deficient subject than in ALDH1 normal subjects. Changes in Ac-CHO in blood were also analyzed in vitro. Ac-CHO metabolism by RBC from the ALDH1 deficient subjects was clearly slower than in those from controls. These results indicate that ALDH1 plays an important role in the metabolism of Ac-CHO in blood.
人类肝脏中至少存在四种类型的乙醛脱氢酶（ALDH）同工酶：乙醛（Ac-CHO）主要由ALDH2代谢。然而，由于ALDH1缺乏症较为罕见，其在Ac-CHO代谢中的作用尚不清楚。在本研究中，分析了一名同时为ALDH2等位基因杂合子的ALDH1缺乏症患者以及ALDH1正常的受试者血液中Ac-CHO水平的变化，以阐明ALDH1在Ac-CHO代谢中的作用。通过对红细胞（RBC）中的ALDH进行等电聚焦分析，在一名男性受试者中未检测到ALDH1条带，表明其存在ALDH1缺乏症。在该受试者中，ALDH1活性几乎为零，但其妻子和两个孩子的活性正常。分析了少量乙醇摄入后血液中Ac-CHO水平的系列变化。ALDH1缺乏症受试者与ALDH1正常受试者的Ac-CHO峰值水平并无差异。然而，缺乏症受试者中Ac-CHO从峰值下降的速度明显慢于ALDH1正常受试者。还在体外分析了血液中Ac-CHO的变化。来自ALDH1缺乏症受试者的红细胞对Ac-CHO的代谢明显慢于对照组。这些结果表明，ALDH1在血液中Ac-CHO的代谢中起重要作用。
