Oestrone Sulphatase Activity of the Rat Uterus in Different Hormonal States

Utaaker, Edle; Støa, K. F.

doi:10.1159/000179285

Cited by 17 publications

(3 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Preliminary tests were run to establish conversion rates and incubation conditions so that the formation of product was linear when less than 10% of the substrate were transformed. Steroid sulphatase activity was assayed according to Utaaker and Støa (1980) with slight modifications. Briefly, 50 ll of [6,7-3 H] E1S (equivalent to 22 000 dpm or 0.19 pmol) and 50 ll of non-labelled E1S (equivalent to 0, 1, 2, 4, 8, 16 and 32 lM) using Ringer-Hepes buffer with 0.1% bovine serum albumin (RH-BSA buffer) and an 50 ll solution containing approximately 0.29 mg protein as the StS source (5 ll of microsomal portion +45 ll of RH-BSA buffer), were pipetted into 15 ml Wheaton reaction tubes.…”

Section: Incubationsmentioning

confidence: 99%

Expression and Activity of Steroid Sulphatase in the Boar Testis

Mutembei¹,

Kowalewski²,

Ugele³

et al. 2009

Reprod Domestic Animals

View full text Add to dashboard Cite

Oestrogens are essential for male fertility targeting the testicular-epididymal compartment. However, the underlying mechanisms are only vaguely known and species specificities must be considered. The boar has a remarkably high testicular-oestrogen output, with the biologically inactive oestrone-sulphate being the major oestrogen occurring in the testicular vein. In the boar testis and epididymis, activity of steroid sulphatase (StS) and oestrogen sulphotransferase has been demonstrated. Thus apart from their synthesis in Leydig cells, provision of biologically active free oestrone seems also to depend on the activity and localization of these enzymes. Our aim was to establish expression patterns and activity of StS in boar testis. Testes were randomly collected from healthy boars and allotted to five age groups, five animals in each, aged 50, 100, 150, 200 and 250 days. Three extra boars aged over 250 days were castrated to obtain fresh tissue for enzyme activity tests. Immunohistochemistry detected StS only in the cytoplasm of Leydig cells and - except for day-50 group in which 65.1 +/- 4.9% (X +/- SD) of the cells were positive - expression was constant with virtually all the cells staining positive. RT-PCR and in situ hybridization confirmed expression and localization of StS mRNA. The V(max) and K(m) value (X +/- SD) for StS was 24.05 +/- 0.3 fmol/s/microg protein and 2.15 +/- 0.12 microM. These data suggest that StS within the Leydig cells of the boar is involved in modulation of testicular oestrogen bioavailability and that the site of sulpho-conjugation is not the testis but a different compartment of the testes-epididymidis complex.

show abstract

Section: Incubationsmentioning

confidence: 99%

Expression and Activity of Steroid Sulphatase in the Boar Testis

Mutembei¹,

Kowalewski²,

Ugele³

et al. 2009

Reprod Domestic Animals

View full text Add to dashboard Cite

show abstract

“…Synthesis of the tritiated E1S was determined with a liquid scintillation counter (Beckman LS-6500, Beckman Coulter, Fullerton, CA). The STS activity was assayed according to Utaaker et al (28) with slight modifications. Briefly, enzyme solution (ϳ0.2 mg protein) was mixed with E1S containing [6,7-3 H] E1S (1.6 ϫ 10 5 dpm, 0.5 pmol/liter) at 20 m and added to a reaction volume up to 0.15 ml with PBS (Ca 2ϩ free) containing 25 mm sucrose and 4 mm nicotinamide.…”

Section: Enzyme Assaymentioning

confidence: 99%

Systemic Distribution of Steroid Sulfatase and Estrogen Sulfotransferase in Human Adult and Fetal Tissues

Miki

Nakata

Suzuki

et al. 2002

The Journal of Clinical Endocrinology &Amp; Metabolism

154

125

View full text Add to dashboard Cite

Estrogens play a key role in various target tissues. Enzymes involved in the biosynthesis and metabolism of these sex steroids also regulate estrogenic actions in these tissues. Estrone sulfate (E1S) is a major circulating plasma estrogen that is converted into the biologically active estrogen, estrone (E1), by steroid sulfatase (STS). E1 is also sulfated and reverted into E1S by estrogen sulfotransferase (EST). These two enzymes have recently been shown to play important roles in the in situ estrogen actions of various sex steroid-dependent human tumors. However, the distribution of STS and EST in normal adult and fetal human tissues remains largely unknown. Therefore, in this study, in addition to examining the tissue distribution of both STS and EST mRNA in human adult and fetal tissues using RT followed by quantitative PCR, we studied the activity of these enzymes using 3 H-labeled E1/E1S as substrates in the homogenates of various human adult tissues. We also examined the localization of STS and EST protein in human adult and fetal tissues using immunohistochemistry, and that of EST mRNA in the adult kidney using laser dissection microscopy and PCR. STS mRNA, enzyme activity, and immunoreactivity were either absent or detected at very low levels in all adult and fetal tissues examined in this study. EST mRNA expression, however, was detected in all of the tissues examined, except for adult spleen and pancreas. EST enzyme activities were consistent with those of mRNA expression in the great majority of the tissues examined. Marked EST immunoreactivity was detected in hepatocytes, adrenal gland (adult, zona fasciculate to the reticularis; fetus, fetal zone), and epithelial cells of the gastrointestinal tract, smooth muscle cells of the tunica media in aorta, Leydig cells of the testis, and syncytiotrophoblast of the placenta. Patterns of EST immunolocalization were similar between adult and fetal human tissues, but EST immunoreactivity was detected in the urinary tubules of adult kidney, whereas in the fetal kidney, it was localized in the interstitial cells surrounding the urinary tubules. In the adult kidney, the presence of EST mRNA was also confirmed in the cells of urinary tubules using laser dissection microscopy and RT-PCR.Although the number of human tissues available for examination in this study was limited, our results suggest that between the enzymes involved in estrogen activation or inactivation, EST and not STS is the more widely expressed enzyme in various peripheral tissues in humans. We speculate that EST may play an important role in protecting peripheral tissues from possible excessive estrogenic effects. (J Clin Endocrinol Metab 87: 5760 -5768, 2002)

show abstract

“…Synthesis of the tritiated E1S was determined with a liquid scintillation counter (LC-6500; Beckman). The STS activity was assayed according to Utaaker and colleagues 49 with slight modifications. Briefly, enzyme solution (ϳ0.2 mg protein) was mixed with E1S containing [6,7-3 H] E1S (1.6 ϫ 105 dpm, 0.5 pmol/L) at 20 mol/L, and added to a reaction volume up to 0.15 ml with PBS (Ϫ) containing 25 mmol/L sucrose and 4 mmol/L of nicotinamide.…”

Section: Enzyme Assaymentioning

confidence: 99%

Steroid Sulfatase and Estrogen Sulfotransferase in the Atherosclerotic Human Aorta

Nakamura

Miki

Suzuki

et al. 2003

The American Journal of Pathology

View full text Add to dashboard Cite

Various epidemiological studies have demonstrated a relatively low incidence of cardiovascular events in premenopausal women and its marked increment after menopause. In addition, estrogens have been postulated to exert direct anti-atherogenic effects via binding to estrogen receptors in vascular smooth muscle cells (VSMCs). However, not all postmenopausal women develop atherosclerosis despite decreased levels of serum estrogen. Therefore, we believe it is important to examine the status of estrogen metabolism in situ in the human cardiovascular system. Estrone sulfate (E1S) is a major circulating plasma estrogen that is converted into the biologically active estrogen, estrone (E1) by steroid sulfatase (STS). E1 is also sulfated and reverted into E1S by estrogen sulfotransferase (EST). These two enzymes have recently been shown to play important roles in the in situ estrogen actions of estrogen-dependent human tissues and various sex steroid-dependent tumors. STS and EST, however, have not been studied in detail in the human vascular system associated with atherosclerotic changes. In the present study, we evaluated the relative abundance of STS-and ESTimmunoreactive protein and mRNA expression in human aorta using immunohistochemistry and reverse transcription followed by quantitative polymerase chain reaction in addition to enzyme activity. STS expression levels were found to be significantly higher in the VSMCs obtained from female aortas with mild atherosclerotic changes than in those with severe atherosclerotic changes and in male aortas regardless of atherosclerotic changes. EST expression levels in the VSMCs of these aortas, however, were significantly higher in female aortas with severe atherosclerotic changes and in male aortas than in female aortas with mild atherosclerotic changes. We believe it is important to examine factors regulating the expression and activity of these estrogen-metabolizing enzymes in the human aorta. Various cytokines have been proposed to function as regulators of these enzymes in other tissues. In the present study, we studied the effects of interleukin (IL)-1␤, known to be produced in human atherosclerotic lesions, on the expression of these enzymes using cultured human VSMCs originally obtained from a female patient. IL-1␤ markedly inhibited the expression of STS mRNA and enzyme activity, but stimulated the expression of EST mRNA and enzyme activity. In addition, IL-1␤ also reduced E2 production from E1S and E1 in VSMCs.Results from the present study seem to suggest that the expression levels of both STS and EST mRNA and activity may be significantly associated with the degree of atherosclerotic changes in the female aorta, which may be related to cytokines produced in situ, such as IL-1␤, in human atherosclerotic lesions. Various epidemiological studies have reported a relatively low incidence of cardiovascular events in premenopausal women and its marked increment after menopause.1 Estrogen has, therefore, been proposed as a cardioprotective agent, especially in women.2 In ...

show abstract

Oestrone Sulphatase Activity of the Rat Uterus in Different Hormonal States

Cited by 17 publications

References 4 publications

Expression and Activity of Steroid Sulphatase in the Boar Testis

Expression and Activity of Steroid Sulphatase in the Boar Testis

Systemic Distribution of Steroid Sulfatase and Estrogen Sulfotransferase in Human Adult and Fetal Tissues

Steroid Sulfatase and Estrogen Sulfotransferase in the Atherosclerotic Human Aorta

Contact Info

Product

Resources

About