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Manfred Donike - One of the best experts on this subject based on the ideXlab platform.

  • Metabolism of boldenone in man: gas chromatographic/mass spectrometric identification of urinary excreted metabolites and determination of excretion rates.
    Journal of Mass Spectrometry, 2005
    Co-Authors: Wilhelm Schänzer, Manfred Donike
    Abstract:

    Urinary metabolites of boldenone (androsta-1,4-dien-17 beta-ol-3-one) following oral administration of boldenone (doses from 11 to 80 mg) to man were isolated from urine via XAD-2 adsorption and enzymatic hydrolysis with beta-glucuronidase from Escherichia coli. The isolated metabolites were derivatized with N-methyl-N-trimethylsilyltri- fluoroacetamide/trimethyliodosilane and analysed by gas chromatography/mass spectrometry with electron impact (EI) ionization at 70 eV. Boldenone (I) and four metabolites were identified after hydrolysis of the urine with beta-glucuronidase: 5 beta-androst-1-en-17 beta-ol-3-one (II), 5 beta-androst-1-ene-3 alpha, 17 beta-diol (III), 5 beta-androst-1-en-3 alpha-ol-17-one (IV) and 5 beta-androst-1-en-6 beta-ol-3,17-dione (V). Five further metabolites in low concentration were identified without enzymatic hydrolysis after treatment of the urine with potassium carbonate: 5 beta-androst-1-ene-3,17-dione (VI), 5 alpha-androst-1-ene-3,17-dione (VII), androsta-1,4-diene-3,17-dione (VIII), androsta-1,4-diene-6 beta,17 beta-diol-3-one (IX) and androsta-1,4-dien-6 beta-ol-3,17-dione (X). The identification of the metabolites is based on the gas chromatography retention index, high-performance liquid chromatography retention, EI mass spectrum, chemical reactions of the isolated metabolites, and synthesis of metabolites II, III, IV, VI and VII. The EI mass spectra of the bis-trimethylsilyl derivatives of boldenone and its metabolites display all intense molecular ions, M-15 ions and fragment ions originating from cleavage of the B-ring. The excreted metabolites can be separated in basic extractable labile conjugates and in stable conjugates. More than 95% of metabolites are excreted as stable conjugates.

  • metabolism of boldenone in man gas chromatographic mass spectrometric identification of urinary excreted metabolites and determination of excretion rates
    Journal of Mass Spectrometry, 1992
    Co-Authors: Wilhelm Schänzer, Manfred Donike
    Abstract:

    Urinary metabolites of boldenone (androsta-1,4-dien-17 beta-ol-3-one) following oral administration of boldenone (doses from 11 to 80 mg) to man were isolated from urine via XAD-2 adsorption and enzymatic hydrolysis with beta-glucuronidase from Escherichia coli. The isolated metabolites were derivatized with N-methyl-N-trimethylsilyltri- fluoroacetamide/trimethyliodosilane and analysed by gas chromatography/mass spectrometry with electron impact (EI) ionization at 70 eV. Boldenone (I) and four metabolites were identified after hydrolysis of the urine with beta-glucuronidase: 5 beta-androst-1-en-17 beta-ol-3-one (II), 5 beta-androst-1-ene-3 alpha, 17 beta-diol (III), 5 beta-androst-1-en-3 alpha-ol-17-one (IV) and 5 beta-androst-1-en-6 beta-ol-3,17-dione (V). Five further metabolites in low concentration were identified without enzymatic hydrolysis after treatment of the urine with potassium carbonate: 5 beta-androst-1-ene-3,17-dione (VI), 5 alpha-androst-1-ene-3,17-dione (VII), androsta-1,4-diene-3,17-dione (VIII), androsta-1,4-diene-6 beta,17 beta-diol-3-one (IX) and androsta-1,4-dien-6 beta-ol-3,17-dione (X). The identification of the metabolites is based on the gas chromatography retention index, high-performance liquid chromatography retention, EI mass spectrum, chemical reactions of the isolated metabolites, and synthesis of metabolites II, III, IV, VI and VII. The EI mass spectra of the bis-trimethylsilyl derivatives of boldenone and its metabolites display all intense molecular ions, M-15 ions and fragment ions originating from cleavage of the B-ring. The excreted metabolites can be separated in basic extractable labile conjugates and in stable conjugates. More than 95% of metabolites are excreted as stable conjugates.

Wilhelm Schänzer - One of the best experts on this subject based on the ideXlab platform.

  • Metabolism of boldenone in man: gas chromatographic/mass spectrometric identification of urinary excreted metabolites and determination of excretion rates.
    Journal of Mass Spectrometry, 2005
    Co-Authors: Wilhelm Schänzer, Manfred Donike
    Abstract:

    Urinary metabolites of boldenone (androsta-1,4-dien-17 beta-ol-3-one) following oral administration of boldenone (doses from 11 to 80 mg) to man were isolated from urine via XAD-2 adsorption and enzymatic hydrolysis with beta-glucuronidase from Escherichia coli. The isolated metabolites were derivatized with N-methyl-N-trimethylsilyltri- fluoroacetamide/trimethyliodosilane and analysed by gas chromatography/mass spectrometry with electron impact (EI) ionization at 70 eV. Boldenone (I) and four metabolites were identified after hydrolysis of the urine with beta-glucuronidase: 5 beta-androst-1-en-17 beta-ol-3-one (II), 5 beta-androst-1-ene-3 alpha, 17 beta-diol (III), 5 beta-androst-1-en-3 alpha-ol-17-one (IV) and 5 beta-androst-1-en-6 beta-ol-3,17-dione (V). Five further metabolites in low concentration were identified without enzymatic hydrolysis after treatment of the urine with potassium carbonate: 5 beta-androst-1-ene-3,17-dione (VI), 5 alpha-androst-1-ene-3,17-dione (VII), androsta-1,4-diene-3,17-dione (VIII), androsta-1,4-diene-6 beta,17 beta-diol-3-one (IX) and androsta-1,4-dien-6 beta-ol-3,17-dione (X). The identification of the metabolites is based on the gas chromatography retention index, high-performance liquid chromatography retention, EI mass spectrum, chemical reactions of the isolated metabolites, and synthesis of metabolites II, III, IV, VI and VII. The EI mass spectra of the bis-trimethylsilyl derivatives of boldenone and its metabolites display all intense molecular ions, M-15 ions and fragment ions originating from cleavage of the B-ring. The excreted metabolites can be separated in basic extractable labile conjugates and in stable conjugates. More than 95% of metabolites are excreted as stable conjugates.

  • metabolism of boldenone in man gas chromatographic mass spectrometric identification of urinary excreted metabolites and determination of excretion rates
    Journal of Mass Spectrometry, 1992
    Co-Authors: Wilhelm Schänzer, Manfred Donike
    Abstract:

    Urinary metabolites of boldenone (androsta-1,4-dien-17 beta-ol-3-one) following oral administration of boldenone (doses from 11 to 80 mg) to man were isolated from urine via XAD-2 adsorption and enzymatic hydrolysis with beta-glucuronidase from Escherichia coli. The isolated metabolites were derivatized with N-methyl-N-trimethylsilyltri- fluoroacetamide/trimethyliodosilane and analysed by gas chromatography/mass spectrometry with electron impact (EI) ionization at 70 eV. Boldenone (I) and four metabolites were identified after hydrolysis of the urine with beta-glucuronidase: 5 beta-androst-1-en-17 beta-ol-3-one (II), 5 beta-androst-1-ene-3 alpha, 17 beta-diol (III), 5 beta-androst-1-en-3 alpha-ol-17-one (IV) and 5 beta-androst-1-en-6 beta-ol-3,17-dione (V). Five further metabolites in low concentration were identified without enzymatic hydrolysis after treatment of the urine with potassium carbonate: 5 beta-androst-1-ene-3,17-dione (VI), 5 alpha-androst-1-ene-3,17-dione (VII), androsta-1,4-diene-3,17-dione (VIII), androsta-1,4-diene-6 beta,17 beta-diol-3-one (IX) and androsta-1,4-dien-6 beta-ol-3,17-dione (X). The identification of the metabolites is based on the gas chromatography retention index, high-performance liquid chromatography retention, EI mass spectrum, chemical reactions of the isolated metabolites, and synthesis of metabolites II, III, IV, VI and VII. The EI mass spectra of the bis-trimethylsilyl derivatives of boldenone and its metabolites display all intense molecular ions, M-15 ions and fragment ions originating from cleavage of the B-ring. The excreted metabolites can be separated in basic extractable labile conjugates and in stable conjugates. More than 95% of metabolites are excreted as stable conjugates.

David E Wildt - One of the best experts on this subject based on the ideXlab platform.

  • urinary 3 alpha 17 beta androstanediol glucuronide is a measure of androgenic status in eld s deer stags cervus eldi thamin
    Biology of Reproduction, 1995
    Co-Authors: Steven L Monfort, E Harvey, L Geurts, Luis R Padilla, H A Simmons, L R Williamson, David E Wildt
    Abstract:

    To determine the primary excretory by-products of testosterone (T), 85 microCi [3H]T was administered i.v. to two adult Eld's deer stags. Blood (10 ml) was collected by jugular venipuncture at 0, 5, 10, 15, 30, 45, 60, 90, 120, 150, 180, 240, and 480 min after isotope infusion, and all urine and feces were collected for 96 h after injection. Seventy percent of labeled circulating steroid was conjugated by 30 min postinfusion. The majority (80.4 +/- 3.2%) of T metabolites were excreted into urine, and 95.0 +/- 0.9% of these were conjugated, 95.8 +/- 0.2% being hydrolyzable with glucuronidase. Seven urinary androgen metabolites, including androstanediol (5 alpha-androstan-3 alpha-17 beta-diol and 5 beta-androstan-3 alpha-17 beta-diol), were identified in glucoronidase-hydrolyzed, ether-extracted Eld's deer urine pools after gas chromatography/mass spectrometry. A double-antibody 125I RIA for 5 alpha-androstanediol-3 alpha, 17 beta-diol,17-glucuronide (3 alpha-diol-G) was validated for unprocessed urine. Longitudinal assessments of urine samples collected from 13 stages for 3 yr revealed biological concordance between fluctuations in urinary 3 alpha-diol-G and serum T, as well as seasonal changes in secondary sexual characteristics. Overall correlation between "same-day" matched serum T and urinary 3 alpha-diol-G was 0.58, (n = 6; p < 0.001). Thus, monitoring urinary 3 alpha-diol-G provides a noninvasive, alternative method for characterizing male endocrine interrelationships in an endangered ungulate species.

Tony Chang - One of the best experts on this subject based on the ideXlab platform.

  • androstanediol and 5 androstenediol profiling for detecting exogenously administered dihydrotestosterone epitestosterone and dehydroepiandrosterone potential use in gas chromatography isotope ratio mass spectrometry
    Steroids, 1997
    Co-Authors: Cedric H L Shackleton, Andy Phillips, Esther Roitman, Tony Chang
    Abstract:

    : The basis of a potential method for confirming intake of four natural androgens (testosterone, epitestosterone, dihydrotestosterone, and dehydroepiandrosterone is presented. The method relies on isolating from urine a steroid fraction containing androstenediol and androstanediol metabolites of these natural steroids and analyzing their 13C content by gas chromatography, combustion, isotope ratio mass spectrometry. The steroids were recovered from urine by conjugate hydrolysis with a Helix pomatia preparation (sulfatase and beta-glucuronidase), Girard T reagent separation to obtain a nonketonic fraction, and Sephadex LH-20 chromatography for purification. Metabolites appropriate for all of the natural steroids could be separated (as diacetates) by gas chromatography on a DB-17 capillary column viz.: 5 alpha (and beta)-androstane-3 alpha,17 alpha-diol (epitestosterone as precursor); 5 alpha (and beta)-androstane-3 alpha,17 beta-diol (testosterone as precursor); 5-androstene-3 beta,17 beta-diol (dehydroepiandrosterone precursor); and 5 alpha-androstane-3 alpha,17 beta- (and 17 alpha-) diol (dihydrotestosterone precursor). Measurement of the 13C content of the specific analytes after ingestion of the androgen precursors demonstrated a lowering of delta 13C/1000 value compared to normal values. Typically, in the male individual studied, delta 13C/1000 values for all components were -26 to -27 before drug administration and -29 to -30 at 6 h after, the latter values reflecting those obtaining for commercial synthetic steroid compared to in vivo synthesized steroid. While generally the metabolism of the steroids was as expected, this was not the case for 5 alpha-dihydrotestosterone. A major metabolite was 5 alpha-androstane-3 alpha,17 alpha-diol, which had presumably been formed by 17 beta/17 alpha isomerization, a process previously known for unnatural anabolics but not for natural hormones. The isolation, purification, and isotope ratio mass spectrometry techniques described may form the basis of a general method for confirming natural steroid misuse by sports participants.

Steven L Monfort - One of the best experts on this subject based on the ideXlab platform.

  • urinary 3 alpha 17 beta androstanediol glucuronide is a measure of androgenic status in eld s deer stags cervus eldi thamin
    Biology of Reproduction, 1995
    Co-Authors: Steven L Monfort, E Harvey, L Geurts, Luis R Padilla, H A Simmons, L R Williamson, David E Wildt
    Abstract:

    To determine the primary excretory by-products of testosterone (T), 85 microCi [3H]T was administered i.v. to two adult Eld's deer stags. Blood (10 ml) was collected by jugular venipuncture at 0, 5, 10, 15, 30, 45, 60, 90, 120, 150, 180, 240, and 480 min after isotope infusion, and all urine and feces were collected for 96 h after injection. Seventy percent of labeled circulating steroid was conjugated by 30 min postinfusion. The majority (80.4 +/- 3.2%) of T metabolites were excreted into urine, and 95.0 +/- 0.9% of these were conjugated, 95.8 +/- 0.2% being hydrolyzable with glucuronidase. Seven urinary androgen metabolites, including androstanediol (5 alpha-androstan-3 alpha-17 beta-diol and 5 beta-androstan-3 alpha-17 beta-diol), were identified in glucoronidase-hydrolyzed, ether-extracted Eld's deer urine pools after gas chromatography/mass spectrometry. A double-antibody 125I RIA for 5 alpha-androstanediol-3 alpha, 17 beta-diol,17-glucuronide (3 alpha-diol-G) was validated for unprocessed urine. Longitudinal assessments of urine samples collected from 13 stages for 3 yr revealed biological concordance between fluctuations in urinary 3 alpha-diol-G and serum T, as well as seasonal changes in secondary sexual characteristics. Overall correlation between "same-day" matched serum T and urinary 3 alpha-diol-G was 0.58, (n = 6; p < 0.001). Thus, monitoring urinary 3 alpha-diol-G provides a noninvasive, alternative method for characterizing male endocrine interrelationships in an endangered ungulate species.