Delayed effects of short-term transdermal application of 7-oxo-dehydroepiandrosterone on its metabolites, some hormonal steroids and relevant proteohormones in healthy male volunteers

A systematic review of the impact of 7-keto-DHEA on body weight

7-Keto-DHEA has been commercially advertised as a dietary supplement to support weight loss. The objective of the present systematic review it to summarize the evidence supporting the use of 7-keto-DHEA in overweight and obese population. The systematic search was conducted in Medline, Embase, Cochrane Library, CINAHL, Web of Science, Scopus, ICTRP, and ClinicalTrials.gov. Additionally, reference lists of eligible studies were considered, and authors of relevant studies were contacted. Two authors independently screened the studies against the inclusion criteria and assessed their risk of bias. In total, 4 out of 686 studies were included in the review. They all held a low risk of bias. Half of them showed a significant reduction in body weight. One study found a decrease in body fat percentage and another one reported a decrease in BMI. Two studies stated an increase in resting metabolic rate. No serious adverse effects were reported. Various possible mechanisms in favor of weight loss are discussed; however, with the evidence currently available, no clear answer can be given regarding 7-keto-DHEA and weight loss. Further studies need to be conducted to clarify the efficacy and safety of this drug before it can be recommended for therapeutic use.

Hormone receptor binding, selectivity and cytotoxicity of steroid D-homo lactone loaded chitosan nanoparticles for the treatment of breast and prostate cancer cells

Chemically modified steroids have a long history as anti-neoplastic drugs. Incorporation of a lactone moiety in the steroid nucleus, as in previously obtained 3β-acetoxy-17-oxa-17a-homoandrost-5-en-16-one (A) and 3β-hidroxy-17-oxa-17a-homoandrost-5-en-16-one (B), often results in enhanced anticancer properties. In this work, chitosan-based (Ch) nanoparticles were created and loaded with potent anticancer steroidal compounds, A and B. Changes to hormone receptor binding and cytotoxicity were then measured. In agreement with our previous results for A and B, A- and B-loaded Ch displayed cytotoxic properties against cancer cell lines. Both A-Ch and B-Ch showed activity toward estrogen negative breast cancer (MDA-MB-231) and androgen negative prostate cancer cell lines (PC-3). Greater selectivity toward cancer cells versus healthy lung fibroblast (MRC-5) was observed for B-Ch particles. Cell viability and cytotoxicity measurements after a recovery period indicate more robust recovery of healthy cells versus malignant cells. Compounds A and B or their Ch-encapsulated forms were shown to have negligible affinity for the ligand binding domain of estrogen receptor β or the androgen receptor in a fluorescent yeast screen, suggesting a lack of estrogenicity and androgenicity. Steroid-loaded chitosan nanoparticles display strong cytotoxicity towards MDA-MB-231 and PC-3 with a lack of hormone activity, indicating their safety and efficacy.

Arimistane: Degradation product or metabolite of 7-oxo-DHEA?

RATIONALE

The instability of androst-5-ene-3,7-dione structures under acidic conditions is known. The formation of arimistane from 7-oxo-DHEA, influenced by the conditions of sample extraction, and mainly derivatization reaction and gas chromatography (GC) injector temperature, was described earlier, potentially leading to misinterpretation of results. By using a liquid chromatography (LC)-mass spectrometry (MS) (LC-MS) we investigated the stability of the 7-oxo-DHEA in two different solvents (methanol and dimethyl sulfoxide [DMSO]), and the arimistane formation after the application common analytical procedures. Additionally, in vitro and in vivo studies of 7-oxo-DHEA were performed.

METHODS

The stability of 7-oxo-DHEA was studied in solutions after 60 days storage at -20°C. In vitro studies were performed by incubating 7-oxo-DHEA with human liver microsomes (HLMs). Healthy volunteers collected urine samples before and after the administration of a single dose of 7-oxo-DHEA. Analyses were performed using high-performance LC (HPLC) coupled to a triple quadrupole mass spectrometer (MS/MS) and GC combustion isotope ratio mass spectrometry (GC-C-IRMS) following HPLC purification.

RESULTS

7-oxo-DHEA was stable after 60 days in DMSO while a protic solvent as methanol promotes the degradation of 7-oxo-DHEA to arimistane. HLM incubations showed no formation of arimistane and the sample preparation only influenced the degradation of 7-oxo-DHEA when solvolysis was applied. After the administration study the presence of arimistane also after the hydrolysis with β-glucuronidase (Escherichia coli) was observed while using β-glucuronidase/arylsulfatase (Helix pomatia) showed the presence of arimistane already in blank samples collected before administration.

CONCLUSIONS

Our results confirm arimistane as a valuable diagnostic marker of 7-oxo-DHEA administration, but also indicate that its formation is due to degradation processes rather than to metabolic biotransformation reactions.

Oxidative metabolism of dehydroepiandrosterone (DHEA) and biologically active oxygenated metabolites of DHEA and epiandrosterone (EpiA)--recent reports

Dehydroepiandrosterone (DHEA) is a multifunctional steroid with a broad range of biological effects in humans and animals. DHEA can be converted to multiple oxygenated metabolites in the brain and peripheral tissues. The mechanisms by which DHEA exerts its effects are not well understood. However, evidence that the effects of DHEA are mediated by its oxygenated metabolites has accumulated. This paper will review the panel of oxygenated DHEA metabolites (7, 16 and 17-hydroxylated derivatives) including a number of 5α-androstane derivatives, such as epiandrosterone (EpiA) metabolites. The most important aspects of the oxidative metabolism of DHEA in the liver, intestine and brain are described. Then, this article reviews the reported biological effects of oxygenated DHEA metabolites from recent findings with a specific focus on cancer, inflammatory and immune processes, osteoporosis, thermogenesis, adipogenesis, the cardiovascular system, the brain and the estrogen and androgen receptors.