A method for the identification and quantification of underivatised steryl sulphates in invertebrates by liquid chromatography (LC) coupled with tandem mass spectrometry (MS) involving a single cleanup step has been developed. Negative electrospray ionisation and positive and negative atmospheric-pressure chemical ionisation (APCI) spectra of steryl sulphate showed pseudomolecular ions ([M+H-H2SO4]+ or [M-H]-). Collision-induced dissociation (CID) was efficient only in positive APCI. LC-MS in negative APCI was least susceptible to interference and possible differences in response factors. The detection limits (signal-to-noise ratio of 3) based on cholest-5-enyl-3-sulphate in positive and negative APCI modes are 3.66 and 0.73 pmol microL(-1), respectively. Calibration plots and response factors for cholest-5-enyl-3-sulphate relative to the internal standard, cholecalciferyl-3-sulphate, in both positive and negative polarities, were linear in the concentration range from 1.22 to 16.4 pmol microL(-1) with good coefficients of determination (R2 > 0.98). It is suggested that the structure elucidation of steryl sulphates is best achieved in CID positive APCI mode, whereas their quantification should be carried out using negative APCI.
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http://dx.doi.org/10.1007/s00216-005-0122-6 | DOI Listing |
Anticancer Res
January 2025
Faculty of Pharmacy, Iryo Sosei University, Fukushima, Japan.
Background/aim: Breast cancer is mostly affected by estrogen, which promotes proliferation, tumorigenesis, and cancer progression. Estrogen sulfotransferase (SULT1E1) catalyzes sulfation to inactivate estrogens, whereas steroid sulfatase (STS) catalyzes estrogen sulfate hydrolysis to activate estrogens in breast cancer cells. Three major organosulfur compounds in garlic (Allium sativum L.
View Article and Find Full Text PDFInt J Dermatol
January 2025
Department of Pathology, School of Medicine, Hunan Normal University, Changsha, People's Republic of China.
Steroids
October 2024
Department of Biological Sciences, Duquesne University, Pittsburgh, PA, USA. Electronic address:
Steroid hormones often circulate in the plasma as inactive sulfated forms, such as estrone sulfate and dehydroepiandrosterone sulfate. The enzyme steroid sulfatase (STS) converts these steroids into active forms, mainly estrogens, in peripheral tissues. STS is present in most tissues, but it occurs at higher levels in certain organs, notably liver and placenta.
View Article and Find Full Text PDFEssays Biochem
December 2024
Institute of Biochemistry and Molecular Genetics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
Sulfatase (STS) and sulfotransferases (SULT) have important role in the biosynthesis and action of steroid hormones. STS catalyzes the hydrolysis of estrone-sulfate (E1-S) and dehydroepiandrosterone-sulfate (DHEA-S), while sulfotransferases catalyze the reverse reaction and require 3-phosphoadenosine-5-phosphosulfate as a sulfate donor. These enzymes control the concentration of active estrogens and androgens in peripheral tissues.
View Article and Find Full Text PDFGenes Brain Behav
June 2024
School of Psychology, Cardiff University, Cardiff, UK.
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