Effects of dietary di(2-ethylhexyl)phthalate, a putative endocrine disrupter, on enzyme activities involved in the metabolism of tryptophan to niacin in rats
Effects of dietary di(2-ethylhexyl)phthalate, a putative endocrine disrupter, on enzyme activities involved in the metabolism of tryptophan to niacin in rats
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DOI：
10.1016/j.bbagen.2004.02.009
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发表时间：
2004-05-03
影响因子：
3
通讯作者：
Shibata, K
中科院分区：
文献类型：
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作者：
Fukuwatari, T;Ohta, M;Shibata, K
我们报道，随着膳食中邻苯二甲酸二（2-乙基己基）酯（DEHP）浓度的增加，色氨酸向烟酸的转化率增加；对照大鼠的转化率约为2.0%，而饲喂3.0% DEHP 饮食的大鼠则增加了约30%。在本研究中，我们研究了 DEHP 转化率的异常增加是否是通过色氨酸代谢为烟酸所涉及的酶活性的改变而发生的。给大鼠喂食含有 0%、0.1%、0.5% 或 1.0% DEHP 的饮食 21 天。测量了肝脏和肾脏中参与生物合成和分解代谢的九种酶的活性。基于先前的研究发现，喹啉酸及其代谢物的形成随着 DEHP 的施用而显着增加，我们提出，2-氨基-3-羧基粘康酸-6-半醛脱羧酶的活性会受到 DEHP 摄入的抑制。然而，我们发现喂食含DEHP饮食的大鼠肝脏和肾脏的活性并没有降低。我们讨论代谢物结果和酶活性之间的差异。 (C) 2004 Elsevier B.V. 保留所有权利。
We have reported that the conversion ratio of tryptophan to niacin increased with increasing dietary concentration of di(2-ethylhexyl)phthalate (DEHP); the conversion ratio was about 2.0% in the control rat, which increased by about 30% in the rat fed with 3.0% DEHP diet. In this study, we investigated whether this abnormal increase in the conversion ratio by DEHP occurred through the alteration of the enzyme activities involved in the metabolism of ttyptophan to niacin. Rats were fed with a diet containing 0%, 0.1%, 0.5%, or 1.0% DEHP for 21 days. The nine kinds of enzyme activities involved in the biosynthesis and catabolism in the liver and kidney were measured. Based on previous findings that the formation of quinolinic acid and its' metabolites significantly increased with DEHP administration, we proposed that the activity of 2-amino-3-carboxymuconate-6-semialdehyde decarboxylase would be inhibited by DEHP intake. However, we found that the activities in the liver and kidney did not decrease in the rat fed with DEHP-containing diet. We discuss the discrepancy between the metabolite results and the enzyme activities. (C) 2004 Elsevier B.V. All rights reserved.