Comparative study of hydrolytic metabolism of dimethyl phthalate, dibutyl phthalate and di(2-ethylhexyl) phthalate by microsomes of various rat tissues
Autor: | Yoko Watanabe, Kyoko Moriguchi, Shigeru Ohta, Hitomi Ozaki, Naoto Uramaru, Tomomichi Sone, Shigeyuki Kitamura, Kazumi Sugihara |
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Rok vydání: | 2017 |
Předmět: |
Male
0301 basic medicine endocrine system Dibutyl phthalate Phthalic Acids Triacylglycerol lipase 010501 environmental sciences Toxicology 01 natural sciences Carboxylesterase Rats Sprague-Dawley 03 medical and health sciences chemistry.chemical_compound Diethylhexyl Phthalate Intestine Small Animals Lipase Pancreas 0105 earth and related environmental sciences Chromatography biology Hydrolysis Phthalate General Medicine Metabolism Dibutyl Phthalate Rats Isoenzymes 030104 developmental biology chemistry Biochemistry Microsomes Liver biology.protein Microsome Dimethyl phthalate Chromatography Liquid Food Science |
Zdroj: | Food and Chemical Toxicology. 100:217-224 |
ISSN: | 0278-6915 |
Popis: | Phthalates are used in food packaging, and are transferred to foods as contaminants. In this study, we examined the hydrolytic metabolism of dimethyl phthalate (DMP), dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) by rat tissue microsomes. We found that carboxylesterase and lipase contribute differently to these activities. When DMP, DBP and DEHP were incubated with rat liver microsomes, DBP was most effectively hydrolyzed to the phthalate monoester, followed by DMP, and the activity toward DEHP was marginal. In contrast, small-intestinal microsomes exhibited relatively higher activity toward long-side-chain phthalates. Pancreatic microsomes showed high activity toward DEHP and DBP. Liver microsomal hydrolase activity toward DMP was markedly inhibited by bis(4-nitrophenyl)phosphate, and could be extracted with Triton X-100. The activity toward DBP and DEHP was partly inhibited by carboxylesterase inhibitor, and was partly solubilized with Triton X-100. Ces1e, Ces1d and Ces1f expressed in COS cells exhibited the highest hydrolase activity toward DBP, showing a similar pattern to that of liver microsomes. Ces1e showed activity towards DMP and DEHP. Pancreatic lipase also hydrolyzed DBP and DEHP. Thus, carboxylesterase and lipase contribute differently to phthalate hydrolysis: short-side-chain phthalates are mainly hydrolyzed by carboxylesterase and long-side-chain phthalates are mainly hydrolyzed by lipase. |
Databáze: | OpenAIRE |
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