Expression of SULT1E1
, SULT2B1, UGT2B7, NQO1, and GSTP1 was decreased.
[38.] Ung D, Nagar S (2007) Variable sulfation of dietary polyphenols by recombinant human sulfotransferase (SULT) 1A1 genetic variants and SULT1E1
. Drug Metab Dispos 35: 740-746.
(2013) presented the results of a crystallographic analysis of the binding of tetrabromo-bisphenol A (TBBPA) and 3-hydroxy2,2',4,4'-tetrabromodiphenyl ether (3-OH-BDE-47) to estrogen sulfotransferase (SULT1E1).
It is highly complex, not well understood, and speculative to extrapolate data on inhibition of enzymes such as SULT1E1 in in vitro assay systems to endocrine-system modulation of selective gene expression, receptor binding, and activation and the production of adverse effects that would characterize endocrine disruption in vivo by additivity of different chemicals competing on the same receptors.
Wang et al., "Estrogen sulfotransferase (SULT1E1
) regulates inflammatory response and lipid metabolism of human endothelial cells via PPAR[gamma]" Molecular and Cellular Endocrinology, vol.
Coffee reduces SULT1E1
expression in human colon carcinoma Caco-2 cells.
It further indicates that the balance between sulfate conjugation by the Phase 2 metabolizing enzyme estrogen sulfotransferases (SULT1E1
) and the removal of the sulfate by the steroid sulfotransferase (STS) is important to store the hormone in an inactive form in the cells [16,17].
The formation of sulfates of 4-hydroxytamoxifen and endoxifen is catalyzed by sulfotransferases (SULTs) SULT1E1
, 1A1, and 2A1 (32, 38).
Other groups have demonstrated the ability of TBBPA and flame retardant metabolites to inhibit estrogen sulfotransferase (SULT1E1
), with IC50 (median inhibitory concentration) values near the [K.sub.m] for estradiol (Hamers et al.
The new research shows how both TBBPA and 3-OH-BDE-47 can bind to an enzyme known as estrogen sulfotransferase (SULT1E1
Sulfation of 17(3-estradiol (E2) by human estrogen sulfotransferase (SULT1E1
) results in loss of binding to the estrogen receptor as well as increased availability for renal excretion, thereby effectively regulating the concentration of E2 (Falany 1997).
At concentrations > 0.15 [micro]M, 3-OH-BaP inhibited its own sulfonation in cytosol fractions that were genotyped for SULT1A1 variants, as well as with expressed SULT1A1*1, SULT1A1*2, and SULT1E1
, but not with SULT1A3 or SULT1B1.