A novel radioimmunoassay of 7-oxo-DHEA and its physiological levels

Kazihnitková, Hana; Zamrazilová, Ludmila; Hill, Martin; Lapčı́k, Oldřich; Pouzar, Vladimı́r; Hampl, Richard

doi:10.1016/j.steroids.2006.12.005

Cited by 11 publications

(8 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For 7ß-OH-DHEA antibody: 7α-OH-DHEA (the opposite epimer), 0.28 %; DHEA, 0.18 %; androstenedione, 0.096 %; testosterone, 0.013 %; cross-reactivity with other hormonal steroids such as cortisol, estradiol, progesterone and dihydrotestosterone was negligible. 7-oxo-DHEA was determined by the RIA method according to Kazihnitková et al (2007).…”

Section: Analytical Methods Analyses Measured By Ria and Irmamentioning

confidence: 99%

Levels of Adipokines and Some Steroids During the Menstrual Cycle

Šrámková¹,

Dušková

Vítků³

et al. 2015

Physiol Res

View full text Add to dashboard Cite

The cyclical effects of hormones during the menstrual cycle (MC) are not just responsible for driving ovulation, but also have significant influence on dietary intake and appetite, as well as psychological and behavioral changes. The aim of our study was to describe changes and relationships between the MC and selected steroids, adipokines and food intake-related hormones.Twenty-seven women with regular menstrual cycles were included in the study, and their hormonal spectrum was measured in regular intervals starting from the first day of their cycle. Classical changes in gonadotropins, estrogens and progesterone during the menstrual cycle are accompanied by less striking but significant changes in 17-hydroxyprogesterone and testosterone. No significant changes show dehydroepiandrosterone and its 7-oxygenated metabolites. Adipokines show a tendency to increase during ovulation, while ghrelin and resistin decrease. There is also a remarkable association of sex hormone-binding globulin on the day of the cycle. Our results demonstrate that changes to adipokines during the menstrual cycle are not substantial, but nonetheless can play a role in the changes of food intake described in the literature. Precise descriptions of physiological changes in healthy women are important in helping us understand the significance of the changes accompanying various pathological states.

show abstract

Section: Analytical Methods Analyses Measured By Ria and Irmamentioning

confidence: 99%

Levels of Adipokines and Some Steroids During the Menstrual Cycle

Šrámková¹,

Dušková

Vítků³

et al. 2015

Physiol Res

View full text Add to dashboard Cite

show abstract

“…Androstenediol (3β,17β-dihydroxy-androst-5-ene) was not found in any of the mixtures, which may suggest that the identified triols (9 and 10) arise directly from the 7α-hydroxy- (7) and 7β-hydroxy-DHEA (8). More than five times lower content of 7-oxo-DHEA (1) indicates that further metabolism of the resulting allyl alcohols is mainly connected with the activity of 17β-HSD.…”

Section: Resultsmentioning

confidence: 92%

“…Thus, this compound is considered to be a safer steroid that could replace the DHEA therapy. [8] As DHEA, it may also have antiproliferative and cytotoxic activity for some tumor cell types. [9] For many years, our team has conducted research on microbial functionalization of compounds of natural origin, including steroid systems.…”

Section: Biohydroxylation Of 7-oxo-dhea a Natural Metabolite Of Dheamentioning

confidence: 99%

“…In contrast to DHEA, 7‐oxo‐DHEA is not a precursor of biologically active androgens or estrogens, which, if present in the body at a level significantly above physiological norm, would increase the risk of hormone‐dependent diseases. Thus, this compound is considered to be a safer steroid that could replace the DHEA therapy . As DHEA, it may also have antiproliferative and cytotoxic activity for some tumor cell types …”

mentioning

confidence: 99%

See 1 more Smart Citation

Biohydroxylation of 7‐oxo‐DHEA, a natural metabolite of DHEA, resulting in formation of new metabolites of potential pharmaceutical interest

2016

View full text Add to dashboard Cite

Metabolism of steroids in healthy and unhealthy human organs is the subject of extensive clinical and biomedical studies. For this kind of investigations, it is essential that the reference samples of new derivatives of natural, physiologically active steroids (especially those difficult to achieve in the chemical synthesis) become available. This study demonstrated for the first time transformation of 7-oxo-DHEA-a natural metabolite of DHEA, using Syncephalastrum racemosum cells. The single-pulse fermentation of substrate produced two new hydroxy metabolites: 1β,3β-dihydroxy-androst-5-en-7,17-dione and 3β,12β-dihydroxy-androst-5-en-7,17-dione, along with the earlier reported 3β,9α-dihydroxy-androst-5-en-7,17-dione and 3β,17β-dihydroxy-androst-5-en-7-one. Simultaneously, the same metabolites, together with small quantities of 7α- and 7β-hydroxy-DHEA, as well as the products of their reduction at the C-17 were obtained after transformation of DHEA under pulse-feeding of the substrate. The observed reactions suggested that this micro-organism contains enzymes exhibiting similar activity to those present in human cells. Thus, the resulting compounds can be considered as potential components of the eukaryotic, including human, metabolome.

show abstract

“…7α-and 7ß-OH-DHEA were measured in plasma by radioimmunoassays using polyclonal rabbit antisera against 7-OH-DHEA-19-(Ocarboxymethyl)oxime conjugates, with bovine serum albumin and radioiodinated homologous derivatives with tyrosine methyl ester as tracers (Lapčík et al, 1998, 1999). 7-oxo-DHEA was determined by the RIA method according to Kazihnitková et al (2007). Intra-and interassay coefficients of variation were 6.7% and 10.0% for 7α-OH-DHEA, and 7.1% and 10.6% for 7ß-OH-DHEA, respectively; the detection limits were 1.06 and 0.95 pg/tube.…”

Section: Steroid Analysismentioning

confidence: 99%

7-oxygenated Derivatives of Dehydroepiandrosterone and Obesity

et al. 2012

View full text Add to dashboard Cite

7-hydroxy/oxo derivatives of dehydroepiandrosterone are potential regulators of the local cortisol activity due to their competition in the cortisolcortisone balance mediated by 11ß-hydroxysteroid dehydrogenase. 7-hydroxydehydroepiandrosterone is marketed as anti-obesity medication, though no clinical study aimed at the benefit of administering 7-oxygenated derivatives of dehydroepiandrosterone has appeared until now. We tried to show whether there exist differences in levels of circulating 7-hydroxy/oxo-dehydroepiandrosterone derivatives between lean and obese boys and girls. From a cohort of adolescents investigated within the frame of anti-obesity programme 10 obese boys and 10 obese girls were compared with age-matched lean boys and girls in their anthropometric data, and concentrations of both epimers of 7-hydroxydehydroepiandrosterone and 7-oxo-dehydroepiandrosterone were determined by the RIA method. The basal levels of 7α-hydroxy-dehydroepiandrosterone were significantly higher in obese boys than in lean boys but not in girls. The association was found for anthropometric parameters and 7α-hydroxy-dehydroepiandrosterone, however again only in boys and not in girls. Higher levels of 7α-hydroxydehydroepiandrosterone its positive association with anthropometric data in obese boys may serve as a sign that, at least in boys, 7-oxygenated 5-ene-steroids may take part in regulating the hormonal signal for fat formation or distribution. Financial Mechanisms, and NT 12342-5/2011 This study was supported by grants: NS/9831-4 of the Internal Grant Agency of the Ministry of Health of the Czech Republic, CZ0123 from Norway through the Norwegian

show abstract

A novel radioimmunoassay of 7-oxo-DHEA and its physiological levels

Cited by 11 publications

References 21 publications

Levels of Adipokines and Some Steroids During the Menstrual Cycle

Levels of Adipokines and Some Steroids During the Menstrual Cycle

Biohydroxylation of 7‐oxo‐DHEA, a natural metabolite of DHEA, resulting in formation of new metabolites of potential pharmaceutical interest

7-oxygenated Derivatives of Dehydroepiandrosterone and Obesity

Contact Info

Product

Resources

About