title: Enzymatic sulfation of tocopherols and tocopherol metabolites by human cytosolic sulfotransferases.
abstract: Tocopherols are essential micronutrients for mammals widely known as potent lipid-soluble antioxidants that are present in cell membranes. Recent studies have demonstrated that most of the carboxychromanol (CEHC), a tocopherol metabolite, in the plasma exists primarily in sulfate- and glucuronide-conjugated forms. To gain insight into the enzymatic sulfation of tocopherols and their metabolites, a systematic investigation was performed using all 14 known human cytosolic sulfotransferases (SULTs). The results showed that the members of the SULT1 family displayed stronger sulfating activities toward tocopherols and their metabolites. These enzymes showed a substrate preference for γ-tocopherol over α-tocopherol and for γ-CEHC over other CEHCs. Using A549 human lung epithelial cells in a metabolic labeling study, a similar trend in the sulfation of tocopherols and CEHCs was observed. Collectively, the results obtained indicate that SULT-mediated enzymatic sulfation of tocopherols and their metabolites is a significant pathway for regulation of the homeostasis and physiological functions of these important compounds.
authors: Department of Biochemistry and Applied Biosciences, University of Miyazaki, Miyazaki, Japan.
authors: Takuyu
authors: T
authors: Hashiguchi
authors: Katsuhisa
authors: K
authors: Kurogi
authors: Yoichi
authors: Y
authors: Sakakibara
authors: Masao
authors: M
authors: Yamasaki
authors: Kazuo
authors: K
authors: Nishiyama
authors: Shin
authors: S
authors: Yasuda
authors: Ming-Cheh
authors: MC
authors: Liu
authors: Masahito
authors: M
authors: Suiko
mesh_terms: D002460:Cell Line; D003600:Cytosol / Q000201:enzymology*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D007700:Kinetics; D013431:Sulfates / Q000378:metabolism*; D015238:Sulfotransferases / Q000378:metabolism*; D024505:Tocopherols / Q000378:metabolism*
chemical_list: D007527:Isoenzymes; D013431:Sulfates; D015238:Sulfotransferases; D024505:Tocopherols