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Charles N. Falany - One of the best experts on this subject based on the ideXlab platform.
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sulfation of fulvestrant by human liver cytosols and recombinant sult1a1 and SULT1E1
Pharmacogenomics and Personalized Medicine, 2011Co-Authors: Vineetha Koroth Edavana, Charles N. Falany, Xinfeng Yu, Ishwori Dhakal, Suzanne Williams, Baitang Ning, Ian T Cook, David J Caldwell, Susan KadlubarAbstract:Fulvestrant (Faslodex™) is a pure antiestrogen that is approved to treat hormone receptor-positive metastatic breast cancer in postmenopausal women. Previous studies have demonstrated that fulvestrant metabolism in humans involves cytochromes P450 and UDP-glucuronosyltransferases (UGTs). To date, fulvestrant sulfation has not been characterized. This study examined fulvestrant sulfation with nine recombinant sulfotransferases and found that only SULT1A1 and SULT1E1 displayed catalytic activity toward this substrate, with Km of 4.2 ± 0.99 and 0.2 ± 0.16 μM, respectively. In vitro assays of 104 human liver cytosols revealed marked individual variability that was highly correlated with β-naphthol sulfation (SULT1A1 diagnostic substrate; r = 0.98, P < 0.0001), but not with 17β-estradiol sulfation (SULT1E1 diagnostic substrate; r = 0.16, P = 0.10). Fulvestrant sulfation was correlated with both SULT1A1*1/2 genotype (P value = 0.023) and copy number (P < 0.0001). These studies suggest that factors influencing SULT1A1/1E1 tissue expression and/or enzymatic activity could influence the efficacy of fulvestrant therapy.
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Hydroxysteroid sulfotransferase 2B1b expression and localization in normal human brain.
Hormone Molecular Biology and Clinical Investigation, 2011Co-Authors: Emily D. Salman, Ona Faye-petersen, Charles N. FalanyAbstract:Steroid sulfonation in the human brain has not been well characterized. The major sulfotransferase (SULT) isoforms that conjugate steroids in humans are SULT1E1, SULT2A1, and SULT2B1b. SULT2B1b catalyzes the sulfonation of 3β-hydroxysteroids, including neurosteroids dehydroepiandrosterone and pregnenolone, as well as cholesterol and several hydroxycholesterols. SULT2B1b mRNA and protein expression were detected in adult and fetal human brain sections, whereas neither mRNA, nor protein expression were identified for SULT1E1 or SULT2A1. Using immunohistochemical analysis, SULT2B1b expression was detected in neurons and oligodendrocytes in adult brain and in epithelial tissues in 28-week-old fetal brain. Sulfonation of cholesterol, oxysterols, and neurosteroids in the brain is apparently catalyzed by SULT2B1b since expression of neither SULT2A1 nor SULT1E1 was detected in human brain sections. SULT2B1b mRNA and protein were also detected in human U373-MG glioblastoma cells. Both mRNA and protein expression of liver X receptor (LXR)-β, but not LXR-α, were detected in U373-MG cells, and LXR-β activation resulted in a decrease in SULT2B1b protein expression. Since hydroxycholesterols are important physiological LXR activators, this suggests a role for regulation of sterol metabolism by LXR and SULT2B1b. Therefore, elucidating key enzymes in the metabolism of cholesterol and neurosteroids could help define the properties of steroid conjugation in the human brain.
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Expression of estrogenicity genes in a lineage cell culture model of human breast cancer progression
Breast Cancer Research and Treatment, 2010Co-Authors: Jiaqi Fu, Charles N. Falany, Josie L. Falany, Thomas A. Kocarek, Amy M. Weise, Bryan J. Thibodeau, Fred R. Miller, Melissa Runge-morrisAbstract:TaqMan Gene Expression assays were used to profile the mRNA expression of estrogen receptor (ERα and ERβ) and estrogen metabolism enzymes including cytosolic sulfotransferases (SULT1E1, SULT1A1, SULT2A1, and SULT2B1), steroid sulfatase (STS), aromatase (CYP19), 17β-hydroxysteroid dehydrogenases (17βHSD1 and 2), CYP1B1, and catechol- O -methyltransferase (COMT) in an MCF10A-derived lineage cell culture model for basal-like human breast cancer progression and in ERα-positive luminal MCF7 breast cancer cells. Low levels of ERα and ERβ mRNA were present in MCF10A-derived cell lines. SULT1E1 mRNA was more abundant in confluent relative to subconfluent MCF10A cells, a non-tumorigenic proliferative breast disease cell line. SULT1E1 was also expressed in preneoplastic MCF10AT1 and MCF10AT1K.cl2 cells, but was markedly repressed in neoplastic MCF10A-derived cell lines as well as in MCF7 cells. Steroid-metabolizing enzymes SULT1A1 and SULT2B1 were only expressed in MCF7 cells. STS and COMT were widely detected across cell lines. Pro-estrogenic 17βHSD1 mRNA was most abundant in neoplastic MCF10CA1a and MCF10DCIS.com cells, while 17βHSD2 mRNA was more prominent in parental MCF10A cells. CYP1B1 mRNA was most abundant in MCF7 cells. Treatment with the histone deacetylase inhibitor trichostatin A (TSA) induced SULT1E1 and CYP19 mRNA but suppressed CYP1B1, STS, COMT, 17βHSD1, and 17βHSD2 mRNA in MCF10A lineage cell lines. In MCF7 cells, TSA treatment suppressed ERα, CYP1B1, STS, COMT, SULT1A1, and SULT2B1 but induced ERβ, CYP19 and SULT2A1 mRNA expression. The results indicate that relative to the MCF7 breast cancer cell line, key determinants of breast estrogen metabolism are differentially regulated in the MCF10A-derived lineage model for breast cancer progression.
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Regulation of hepatic sulfotransferase (SULT) 1E1 expression and effects on estrogenic activity in cystic fibrosis (CF).
The Journal of steroid biochemistry and molecular biology, 2009Co-Authors: Charles N. Falany, Josie L. Falany, Thomas A. Kocarek, Li Li, Dongning He, Teresa W. Wilborn, Melissa Runge-morrisAbstract:Cystic fibrosis (CF) is a major genetic disease in Caucasians affecting 1 in 2500 newborns. Hepatobiliary pathology is a major cause of morbidity and mortality in CF second only to pulmonary disease. SULT1E1 activity is significantly elevated, generally 20-30-fold, in hepatocytes of mouse models of CF. SULT1E1 is responsible for the inactivation of beta-estradiol (E2) at physiological concentrations via conjugation with sulfonate. The increase in SULT1E1 activity results in the alteration of E2-regulated protein expression in CF mouse liver. To investigate the mechanism by which the absence of CFTR in human cholangiocytes induces SULT1E1 expression in hepatocytes, a membrane-separated human MMNK-1 cholangiocyte and human HepG2 hepatocyte co-culture system was developed. The cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in bile duct cholangiocytes but not hepatocytes, whereas SULT1E1 is expressed in hepatocytes but not cholangiocytes. CFTR expression in MMNK-1 cells was inhibited with siRNA by >90% as determined by immunoblot and immunohistochemical analysis. Control and CFTR-siRNA-MMNK-1 cells were co-cultured with HepG2 cells in a Transwell membrane-separated system. After 8h of co-culture, HepG2 cells were removed from exposure to MMNK-1 cells and placed in fresh medium. After 24-48h, expression of SULT1E1 and selected E2-regulated proteins was analyzed in the HepG2 cells. Results demonstrated that SULT1E1 message and activity were selectively induced in HepG2 cells co-cultured with CFTR-deficient MMNK-1 cells. The expression of E2-regulated proteins (IGF-1, GST-P1 and carbonic anhydrase II) was also altered in response to decreased E2 levels. Thus, the loss of CFTR activity in cholangiocytes stimulates the expression of SULT1E1 in hepatocytes by a paracrine mechanism. SULT1E1 expression in HepG2 cells is inducible by sterol mediated liver-X-receptor (LXR) activation although not by progestins that induce SULT1E1 in the endometrium. SULT1E1 induction in the human cholangiocyte/hepatocyte co-culture system is consistent with and supports the results observed in CF mice. The changes in hepatocyte gene expression affect liver biochemistry and may facilitate the development of CF liver disease.
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Regulation of hepatic sulfotransferase (SULT) 1E1 expression and effects on estrogenic activity in cystic fibrosis (CF)
The Journal of Steroid Biochemistry and Molecular Biology, 2009Co-Authors: Charles N. Falany, Josie L. Falany, Thomas A. Kocarek, Li Li, Dongning He, Teresa W. Wilborn, Melissa Runge-morrisAbstract:Cystic fibrosis (CF) is a major genetic disease in Caucasians affecting 1 in 2500 newborns. Hepatobiliary pathology is a major cause of morbidity and mortality in CF second only to pulmonary disease. SULT1E1 activity is significantly elevated, generally 20–30-fold, in hepatocytes of mouse models of CF. SULT1E1 is responsible for the inactivation of β-estradiol (E2) at physiological concentrations via conjugation with sulfonate. The increase in SULT1E1 activity results in the alteration of E2-regulated protein expression in CF mouse liver. To investigate the mechanism by which the absence of CFTR in human cholangiocytes induces SULT1E1 expression in hepatocytes, a membrane-separated human MMNK-1 cholangiocyte and human HepG2 hepatocyte co-culture system was developed. The cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in bile duct cholangiocytes but not hepatocytes, whereas SULT1E1 is expressed in hepatocytes but not cholangiocytes. CFTR expression in MMNK-1 cells was inhibited with siRNA by >90% as determined by immunoblot and immunohistochemical analysis. Control and CFTR-siRNA-MMNK-1 cells were co-cultured with HepG2 cells in a Transwell membrane-separated system. After 8 h of co-culture, HepG2 cells were removed from exposure to MMNK-1 cells and placed in fresh medium. After 24–48 h, expression of SULT1E1 and selected E2-regulated proteins was analyzed in the HepG2 cells. Results demonstrated that SULT1E1 message and activity were selectively induced in HepG2 cells co-cultured with CFTR-deficient MMNK-1 cells. The expression of E2-regulated proteins (IGF-1, GST-P1 and carbonic anhydrase II) was also altered in response to decreased E2 levels. Thus, the loss of CFTR activity in cholangiocytes stimulates the expression of SULT1E1 in hepatocytes by a paracrine mechanism. SULT1E1 expression in HepG2 cells is inducible by sterol mediated liver-X-receptor (LXR) activation although not by progestins that induce SULT1E1 in the endometrium. SULT1E1 induction in the human cholangiocyte/hepatocyte co-culture system is consistent with and supports the results observed in CF mice. The changes in hepatocyte gene expression affect liver biochemistry and may facilitate the development of CF liver disease.
Robert B Gibbs - One of the best experts on this subject based on the ideXlab platform.
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inhibition of estrogen sulfotransferase SULT1E1 est ameliorates ischemic acute kidney injury in mice
Journal of The American Society of Nephrology, 2020Co-Authors: Anne Caroline S Barbosa, Dong Zhou, Youjin Choi, Hungchun Tung, Xinyun Chen, Meishu Xu, Robert B Gibbs, Samuel M Poloyac, Yanping YuAbstract:BACKGROUND Studies have suggested that estrogens may protect mice from AKI. Estrogen sulfotransferase (SULT1E1, or EST) plays an important role in estrogen homeostasis by sulfonating and deactivating estrogens, but studies on the role of SULT1E1 in AKI are lacking. METHODS We used the renal ischemia-reperfusion model to investigate the role of SULT1E1 in AKI. We subjected wild-type mice, SULT1E1 knockout mice, and SULT1E1 knockout mice with liver-specific reconstitution of SULT1E1 expression to bilateral renal ischemia-reperfusion or sham surgery, either in the absence or presence of gonadectomy. We assessed relevant biochemical, histologic, and gene expression markers of kidney injury. We also used wild-type mice treated with the SULT1E1 inhibitor triclosan to determine the effect of pharmacologic inhibition of SULT1E1 on AKI. RESULTS AKI induced the expression of SULT1E1 in a tissue-specific and sex-specific manner. It induced expression of SULT1E1 in the liver in both male and female mice, but SULT1E1 induction in the kidney occurred only in male mice. Genetic knockout or pharmacologic inhibition of SULT1E1 protected mice of both sexes from AKI, independent of the presence of sex hormones. Instead, a gene profiling analysis indicated that the renoprotective effect was associated with increased vitamin D receptor signaling. Liver-specific transgenic reconstitution of SULT1E1 in SULT1E1 knockout mice abolished the protection in male mice but not in female mice, indicating that SULT1E1's effect on AKI was also tissue-specific and sex-specific. CONCLUSIONS SULT1E1 appears to have a novel function in the pathogenesis of AKI. Our findings suggest that inhibitors of SULT1E1 might have therapeutic utility in the clinical management of AKI.
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Inhibition of Estrogen Sulfotransferase (SULT1E1/EST) Ameliorates Ischemic Acute Kidney Injury in Mice.
Journal of The American Society of Nephrology, 2020Co-Authors: Anne Caroline S Barbosa, Dong Zhou, Youjin Choi, Hungchun Tung, Xinyun Chen, Meishu Xu, Robert B Gibbs, Samuel M PoloyacAbstract:BACKGROUND: Studies have suggested that estrogens may protect mice from AKI. Estrogen sulfotransferase (SULT1E1, or EST) plays an important role in estrogen homeostasis by sulfonating and deactivating estrogens, but studies on the role of SULT1E1 in AKI are lacking. METHODS: We used the renal ischemia-reperfusion model to investigate the role of SULT1E1 in AKI. We subjected wild-type mice, SULT1E1 knockout mice, and SULT1E1 knockout mice with liver-specific reconstitution of SULT1E1 expression to bilateral renal ischemia-reperfusion or sham surgery, either in the absence or presence of gonadectomy. We assessed relevant biochemical, histologic, and gene expression markers of kidney injury. We also used wild-type mice treated with the SULT1E1 inhibitor triclosan to determine the effect of pharmacologic inhibition of SULT1E1 on AKI. RESULTS: AKI induced the expression of SULT1E1 in a tissue-specific and sex-specific manner. It induced expression of SULT1E1 in the liver in both male and female mice, but SULT1E1 induction in the kidney occurred only in male mice. Genetic knockout or pharmacologic inhibition of SULT1E1 protected mice of both sexes from AKI, independent of the presence of sex hormones. Instead, a gene profiling analysis indicated that the renoprotective effect was associated with increased vitamin D receptor signaling. Liver-specific transgenic reconstitution of SULT1E1 in SULT1E1 knockout mice abolished the protection in male mice but not in female mice, indicating that SULT1E1's effect on AKI was also tissue-specific and sex-specific. CONCLUSIONS: SULT1E1 appears to have a novel function in the pathogenesis of AKI. Our findings suggest that inhibitors of SULT1E1 might have therapeutic utility in the clinical management of AKI.
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estrogen sulfotransferase est SULT1E1 promotes human adipogenesis lb606
The FASEB Journal, 2014Co-Authors: Chibueze A Ihunnah, Robert B Gibbs, Brian J Philips, Sudheer Ravuri, Levent Kirisci, J P Rubin, Kacey G MarraAbstract:The estrogen sulfotransferase (EST/SULT1E1) is known to catalyze the sulfoconjugation and deactivation of estrogens. The goal of this study is to determine whether and how EST plays a role in human...
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Estrogen sulfotransferase(est/SULT1E1) promotes human adipogenesis (LB606)
The FASEB Journal, 2014Co-Authors: Chibueze A Ihunnah, Robert B Gibbs, Brian J Philips, Sudheer Ravuri, Levent Kirisci, J P Rubin, Kacey G MarraAbstract:The estrogen sulfotransferase (EST/SULT1E1) is known to catalyze the sulfoconjugation and deactivation of estrogens. The goal of this study is to determine whether and how EST plays a role in human...
Kacey G Marra - One of the best experts on this subject based on the ideXlab platform.
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estrogen sulfotransferase est SULT1E1 promotes human adipogenesis lb606
The FASEB Journal, 2014Co-Authors: Chibueze A Ihunnah, Robert B Gibbs, Brian J Philips, Sudheer Ravuri, Levent Kirisci, J P Rubin, Kacey G MarraAbstract:The estrogen sulfotransferase (EST/SULT1E1) is known to catalyze the sulfoconjugation and deactivation of estrogens. The goal of this study is to determine whether and how EST plays a role in human...
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Estrogen sulfotransferase(est/SULT1E1) promotes human adipogenesis (LB606)
The FASEB Journal, 2014Co-Authors: Chibueze A Ihunnah, Robert B Gibbs, Brian J Philips, Sudheer Ravuri, Levent Kirisci, J P Rubin, Kacey G MarraAbstract:The estrogen sulfotransferase (EST/SULT1E1) is known to catalyze the sulfoconjugation and deactivation of estrogens. The goal of this study is to determine whether and how EST plays a role in human...
Gerhard Schuler - One of the best experts on this subject based on the ideXlab platform.
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SULFATION PATHWAYS: Formation and hydrolysis of sulfonated estrogens in the porcine testis and epididymis.
Journal of Molecular Endocrinology, 2018Co-Authors: Gerhard Schuler, B Zimmer, Y Dezhkam, L Tenbusch, Mc Klymiuk, Bernd HoffmannAbstract:: Boars exhibit high concentrations of sulfonated estrogens (SE) mainly originating from the testicular-epididymal compartment. Intriguingly, in porcine Leydig cells, sulfonation of estrogens is colocalized with aromatase and steroid sulfatase (STS), indicating that de novo synthesis of unconjugated estrogens (UE), their sulfonation and hydrolysis of SE occur within the same cell type. So far in boars no plausible concept concerning the role of SE has been put forward. To obtain new information on SE formation and hydrolysis, the porcine testicular-epididymal compartment was screened for the expression of the estrogen-specific sulfotransferase SULT1E1 and STS applying real-time RT-qPCR, Western blot and immunohistochemistry. The epididymal head was identified as the major site of SULT1E1 expression, whereas in the testis, it was virtually undetectable. However, SE tissue concentrations are clearly consistent with the testis as the predominant site of estrogen sulfonation. Results from measurements of estrogen sulfotransferase activity indicate that in the epididymis, SULT1E1 is the relevant enzyme, whereas in the testis, estrogens are sulfonated by a different sulfotransferase with a considerably lower affinity. STS expression and activity was high in the testis (Leydig cells, rete testis epithelium) but also present throughout the epididymis. In the epididymis, SULT1E1 and STS were colocalized in the ductal epithelium, and there was evidence for their apocrine secretion into the ductal lumen. The results suggest that in porcine Leydig cells, SE may be produced as a reservoir to support the levels of bioactive UE via the sulfatase pathway during periods of low activity of the pulsatile testicular steroidogenesis.
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occurrence of sulfonated steroids and ovarian expression of steroid sulfatase and SULT1E1 in cyclic cows
The Journal of Steroid Biochemistry and Molecular Biology, 2017Co-Authors: Carina Blaschka, Gerhard Schuler, Alberto Sanchezguijo, B Zimmer, Sabine Feller, Franziska Kotarski, Stefan A Wudy, C WrenzyckiAbstract:Abstract Historically sulfonated steroids were primarily considered as inactive metabolites destined for elimination. However, more recently they have been increasingly recognized as precursors for the production of bioactive steroids in target tissues and as functional molecules without preceding hydrolysis. In order to comprehensively characterize their occurrence in cyclic cows and their formation and hydrolysis in bovine ovarian steroidogenesis, ovaries from cyclic cows were screened for the expression of oestrogen sulfotransferase (SULTE1) and steroid sulfatase (STS) by Western blot and immunohistochemistry. Moreover, a broad spectrum of 13 sulfonated steroids was measured applying liquid chromatography-tandem mass spectrometry (LC–MS/MS) in blood samples collected from three cycling heifers during defined stages of the ovarian cycle and in fluid obtained from ovarian follicles of different size. SULT1E1 was undetectable in ovarian tissues. For STS only a weak immunostaining was found predominantly in granulosa cells of larger follicles. However, no specific band occurred in Western blot. In blood, concentrations of all sulfonated steroids investigated were below the limit of quantification (LOQ). In follicular fluid, only cholesterol sulfate was measured in considerable concentrations (328.3 ± 63.8 ng/ml). However, the role of cholesterol sulfate in bovine follicular steroidogenesis remains unclear as concentrations were obviously unrelated to follicular size. The remaining sulfonated steroids investigated were undetectable or only slightly exceeded LOQ in a minor proportion of samples. The results are clearly contrary to a role of sulfonated steroids as important precursors, intermediates or products of bovine ovarian steroidogenesis.
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54 IMMUNOLOCALIZATION OF STEROID SULFATASE AND ESTROGEN-SPECIFIC SULFOTRANSFERASE IN BOVINE FOLLICLES
Reproduction Fertility and Development, 2016Co-Authors: Carina Blaschka, Gerhard Schuler, Christine WrenzyckiAbstract:Steroid hormones are regulators in the fine-tuned mechanism of follicular development in cattle. Their concentration and property can be modulated via different processes. Sulfoconjugation via sulfotransferases (SULT) changes them from being hydrophobic to hydrophilic molecules, thereby preventing them from diffusing freely across the lipid bilayer and necessitating a transport system like the sodium-dependent organic anion transporter (SOAT; SLC10A6). In addition, sulfated steroids can no longer bind to their nuclear receptors, rendering them biologically inactive. Steroid sulfatase (STS) removes the sulfate moiety from conjugated steroids, transforming them to the free active forms. Data about the concentration of sulfated steroids in follicular fluid and the expression of the related enzymes are limited in horses and cattle. Recently, transcripts of the corresponding enzymes have been detected in cumulus cells of immature bovine cumulus-oocyte complex. Furthermore, it has been shown that small amounts of sulphated steroids are present in bovine follicular fluid. The objective of the study was to investigate the steroid metabolizing enzymes at the protein level via immunohistochemistry (IHC). Bovine ovaries collected at a slaughterhouse were categorized according to their oestrus cycle stage. Three pairs of ovaries of each cycle stage (proestrus, oestrus, postestrus, interestrus) were collected. Morphological criteria (ovaries: presence/absence of follicles and/or CL, size and number of follicles; closure of the cervix, amount of mucus) were employed to categorize them. Samples for IHC were fixed in formalin. After washing and dehydration, the samples were finally embedded in paraffin and mounted onto blocks. Indirect immunoperoxidase staining methods were applied using the streptavidin-biotin technique for signal enhancement following standard procedures. Tissue sections of 3 µm were mounted onto glass slides, and a polyclonal rabbit anti-human STS and a polyclonal rabbit anti-bovine SULT1E1 primary antibody were used to detect STS or SULT1E1, respectively. Negative controls were included using nonspecific rabbit IgG. The evaluation of the staining was descriptive in relation to a positive control (bovine placenta). Immunostaining for STS was detected in granulosa cells of antral and secondary follicles and in the endothelium of blood vessels, irrespective of the stage of the oestrus cycle. Moreover, staining for SULT1E1 was restricted to granulosa cells in antral follicles, again irrespective of the stage of the oestrus cycle. However, staining intensity for STS and SULT1E1 was only weak. These data indicate for the first time the presence of the steroid metabolising enzymes STS and SULT1E1 in bovine ovaries at the protein level. However, due to the low expression level, further studies are needed to clarify the function. We gratefully acknowledge the financial support of the German Research Foundation (DFG; FOR 1369, WR 154/3–1).
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estrogen specific sulfotransferase SULT1E1 in bovine placentomes inverse levels of mrna and protein in uninucleated trophoblast cells and trophoblast giant cells
Biology of Reproduction, 2014Co-Authors: Marina Polei, Torsten Viergutz, Wolfgang Tomek, Gerhard Schuler, Rainer FurbassAbstract:ABSTRACT The bovine trophoblast produces significant amounts of estrogens. In maternal and fetal blood, estrogens occur predominantly in sulfonated forms, which are unable to bind to estrogen receptors (ESRs). However, estrogens may act as local factors in ESR-positive trophoblast cells or in the adjacent caruncular epithelium, which in addition to ESR highly expresses steroid sulfatase. Estrogen sulfonation is catalyzed by the cytosolic enzyme SULT1E1. Previous studies clearly indicated the trophoblast as the primary site of estrogen sulfonation. However, investigations into the cellular localization of SULT1E1 yielded conflicting results. In situ hybridization studies detected SULT1E1 mRNA only in trophoblast giant cells (TGCs), whereas in immunohistochemical experiments the SULT1E1 protein was virtually restricted to uninucleated trophoblast cells (UTCs). The aim of this work was to resolve this conflict by analyzing SULT1E1 expression in isolated UTCs and TGCs. Highly enriched pools of UTCs and TGCs w...
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expression of SULT1E1 protein in bovine placentomes evidence for localization in uninucleated trophoblast cells
Placenta, 2011Co-Authors: P Khatri, G Frenette, R Sullivan, B Hoffmann, Gerhard SchulerAbstract:Abstract The bovine placenta produces considerable amounts of pregnancy-associated estrogens, predominantly estrone sulfate, which does not interact with classical nuclear estrogen receptors. Thus, bovine placental estrogens may rather act as local regulatory factors than as hormones in a classical sense. To obtain information on the local availability of free estrogens in bovine placentomes, the expression pattern of the estrogen specific sulfotransferase SULT1E1 was characterized using antisera against the bovine and human enzyme, respectively. In western blot both antisera detected a band of the expected molecular weight (approx. 33 kDa) in placentomes and fetal liver. In immunohistochemistry the two antisera yielded virtually identical results. In placentomes distinct staining was restricted to the cytosol of uninucleated trophoblast cells (UTC). The staining pattern in UTC, immature and mature trophoblast giant cells (TGC) is consistent with a down-regulation of SULT1E1 during TGC differentiation. During early and midgestation staining intensity in UTC was higher in the trophoblast covering the chorionic plate and basal parts of stem villi compared to other regions of the villous tree, whereas during late gestation and at parturition an almost ubiquitous distinct staining of UTC was found. Correspondingly, relative SULT1E1-mRNA levels as measured by quantitative real-time RT-PCR increased significantly during late gestation (p = 0.0043). Comparative measurements showed that SULT1E1-mRNA levels in adult bovine organs were considerably lower compared to placentomes and fetal liver. The results suggest that the activities of free estrogens produced in bovine TGC are curtailed by SULT1E1 expressed in UTC and in fetal liver. Bovine pregnancy-associated estrogens produced in trophoblast giant cells are predominantly sulfonated in uninucleated trophoblast cells.
Masahiko Negishi - One of the best experts on this subject based on the ideXlab platform.
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RORα Phosphorylation by Casein Kinase 1α as Glucose Signal to Regulate Estrogen Sulfation in Human Liver Cells.
Biochemical Journal, 2020Co-Authors: Hao Hu, Masahiko NegishiAbstract:Estrogen sulfotransferase (SULT1E1) metabolically inactivates estrogen and SULT1E1 expression is tightly regulated by multiple nuclear receptors. Human fetal, but not adult, livers express appreciable amounts of SULT1E1 protein, which is mimicked in human hepatoma-derived HepG2 cells cultured in high glucose (450 mg/dL) medium. Here, we have investigated this glucose signal that leads to phosphorylation of nuclear receptor RORα (NR1F1) at Ser100 and the transcription mechanism by which phosphorylated RORα transduces this signal to nuclear receptor HNF4α, activating the SULT1E1 promoter. The promoter is repressed by non-phosphorylated RORα which binds a distal enhancer (-943/-922 bp) and interacts with and represses HNF4α-mediated transcription. In response to high glucose, RORα becomes phosphorylated at Ser100 and reverses its repression of HNF4α promoter activation. Moreover, the casein kinase CK1α, which is identified in an enhancer-bound nuclear protein complex, phosphorylates Ser100 in in vitro kinase assays. During these dynamic processes, both RORα and HNF4α remain on the enhancer. Thus, RORα utilizes phosphorylation to integrate HNF4α and transduces the glucose signal to regulate the SULT1E1 gene in HepG2 cells and this phosphorylation-mediated mechanism may also regulate SULT1E1 expressions in the human liver.
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Nuclear receptor CAR-ERα signaling regulates the estrogen sulfotransferase gene in the liver.
Scientific Reports, 2020Co-Authors: Myeongjin Yi, Muluneh Fashe, Shingo Arakawa, Rick Moore, Tatsuya Sueyoshi, Masahiko NegishiAbstract:Estrogen sulfotransferase (SULT1E1) inactivates estrogen and regulates its metabolic homeostats. Whereas SULT1E1 is expressed low in the liver of adult mice, it is induced by phenobarbital (PB) treatment or spontaneously in diabetic livers via nuclear receptors. Utilizing constitutive active/androstane receptor (CAR) KO, estrogen receptor α (ERα KO, phosphorylation-blocked ERα S216A KI mice, it is now demonstrated that, after being activated by PB, CAR binds and recruits ERα onto the Sulte1 promoter for subsequent phosphorylation at Ser216. This phosphorylation tightens CAR interacting with ERα and to activates the promoter. Hepatic SULT1E1 mRNA levels are constitutively up-regulated in type 1 diabetic Akita mice; CAR spontaneously accumulates in the nucleus and activates the SULT1E1 promoter by recruiting phosphorylated ERα in the liver as observed with PB-induced livers. Thus, this CAR-phosphorylated ERα signaling enables these two nuclear receptors to communicate, activating the SULT1E1 gene in response to either PB or diabetes in mice. ERα phosphorylation may integrate CAR into estrogen actions, providing insights into understanding drug-hormone interactions in clinical therapy.
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phenobarbital induced phosphorylation converts nuclear receptor rorα from a repressor to an activator of the estrogen sulfotransferase gene SULT1E1 in mouse livers
FEBS Letters, 2018Co-Authors: Muluneh Fashe, Myeongjin Yi, Rick Moore, Takuyu Hashiguchi, Masahiko NegishiAbstract:: The estrogen sulfotransferase SULT1E1 sulfates and inactivates estrogen, which is reactivated via desulfation by steroid sulfatase, thus regulating estrogen homeostasis. Phenobarbital (PB), a clinical sedative, activates SULT1E1 gene transcription in mouse livers. Here, the molecular mechanism by which the nuclear receptors CAR, which is targeted by PB, and RORα communicate through phosphorylation to regulate SULT1E1 activation has been studied. RORα, a basal activity repressor of the SULT1E1 promoter, becomes phosphorylated at serine 100 and converts to an activator of the SULT1E1 promoter in response to PB. CAR regulates both the RORα phosphorylation and conversion. Our findings suggest that PB signals CAR to communicate with RORα via serine 100 phosphorylation, converting RORα from transcription repressor to activator of the SULT1E1 gene and inducing SULT1E1 expression in mouse livers.
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liganded pregnane x receptor represses the human sulfotransferase SULT1E1 promoter through disrupting its chromatin structure
Nucleic Acids Research, 2011Co-Authors: Susumu Kodama, Fardin Hosseinpour, Joyce A Goldstein, Masahiko NegishiAbstract:: Pregnane X receptor (PXR), acting as a xenobiotic-activated transcription factor, regulates the hepatic metabolism of therapeutics as well as endobiotics such as steroid hormones. Given our finding that PXR activation by rifampicin (RIF) represses the estrogen sulfotransferase (SULT1E1) gene in human primary hepatocytes and hepatocellular carcinoma Huh7 cells, here we have investigated the molecular mechanism of this repression. First the PXR-responsive enhancer was delineated to a 100 bp sequence (-1000/-901), which contains three half sites that constitute the overlapping direct repeat 1 (DR1) and direct repeat 2 (DR2) motifs and two forkhead factor binding sites. siRNA knockdown, chromatin immunoprecipitation and chromatin conformation capture assays were employed to demonstrate that hepatocyte nuclear factor 4α (HNF4α) bound to the PXR-responsive enhancer, and activated the enhancer by looping its position close to the proximal promoter. Upon activation by RIF, PXR indirectly interacted with the enhancer, decreasing the interaction with HNF4α and dissolving the looped SULT1E1 promoter with deacetylation of histone 3. Removal of the DR sites from the enhancer hampers the ability of HNF4α to loop the promoter and that of PXR to repress the promoter activity. Thus, PXR represses human SULT1E1, possibly attenuating the inactivation of estrogen.
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garlic extract diallyl sulfide das activates nuclear receptor car to induce the SULT1E1 gene in mouse liver
PLOS ONE, 2011Co-Authors: Tatsuya Sueyoshi, Rick Moore, William R Green, Kellie Vinal, Tyler S Woodrum, Masahiko NegishiAbstract:Constituent chemicals in garlic extract are known to induce phase I and phase II enzymes in rodent livers. Here we have utilized Car+/+ and Car−/− mice to demonstrate that the nuclear xenobiotic receptor CAR regulated the induction of the estrogen sulfotransferase SULT1E1 gene by diallyl sulfide (DAS) treatment in mouse liver. DAS treatment caused CAR accumulation in the nucleus, resulting in a remarkable increase of SULT1E1 mRNA (3,200 fold) and protein in the livers of Car+/+ females but not of Car−/− female mice. DAS also induced other CAR-regulated genes such as Cyp2b10, Cyp3a11 and Gadd45β. Compared with the rapid increase of these mRNA levels, which began as early as 6 hourrs after DAS treatment, the levels of SULT1E1 mRNA began increasing after 24 hours. This slow response to DAS suggested that CAR required an additional factor to activate the SULT1E1 gene or that this activation was indirect. Despite the remarkable induction of SULT1E1, there was no decrease in the serum levels of endogenous E2 or increase of estrone sulfate while the clearance of exogenously administrated E2 was accelerated in DAS treated mice.
