Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Language
Publication year range
1.
Gynecol Endocrinol ; 27(12): 1077-83, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21480767

ABSTRACT

Based on recent findings that hormones can emit electrons () from their excited singlet state in polar media, it was of importance to study a possible mutual interaction of progesterone (PRG) and testosterone (TES) in this respect. Hormones of highest purity were dissolved in an air-free mixture of 40% triply distilled water and 60% ethanol, because the hormones are unsoluble in water. As energy source for substrate excitation in singlet state served a monochromatic UV-light (254 nm), the emitted electrons were scavenged by chloroethanol, whereby the quantum yield of produced Cl⁻ ions, Q (Cl⁻), is equal to Q(e⁻(aq)). Hormone degradation initiated by the electron emission was studied by HPLC method, using a Zorbax Eclipse XDB-C18 column (150 mm x 4.6 mm, 5 µm). The quantum yield of emitted e⁻(aq), Q(e⁻(aq)), from TES was 3.6 times higher than that from PRG, which is explained by the different molecular structures of the hormones. Observed 2nd and 3rd maxima of electron emission indicate the ability of TES and PRG products to also eject e⁻(aq), but with lower yield. It can be stated that a part of the emitted electrons from TES are consumed by PRG⁺ leading to a partial regeneration of hormone. The present results offer a deeper insight in the biological behavior of hormones.


Subject(s)
Electrons , Photolysis/drug effects , Progesterone/pharmacology , Testosterone/metabolism , Chromatography, High Pressure Liquid , Ethanol/chemistry , Ethanol/pharmacology , Humans , Models, Chemical , Oxidation-Reduction/drug effects , Oxidation-Reduction/radiation effects , Oxygen/chemistry , Oxygen/pharmacology , Photoelectron Spectroscopy , Quantum Theory , Testosterone/chemistry , Testosterone/radiation effects , Ultraviolet Rays , Water/chemistry , Water/pharmacology
2.
Gynecol Endocrinol ; 27(7): 496-503, 2011 Jul.
Article in English | MEDLINE | ID: mdl-20586552

ABSTRACT

Recent studies showed that hormones like progesterone, testosterone, etc. can eject [Formula: see text] (solvated electrons). By means of electron transfer processes via the brain, the hormones communicate with other biological systems in the organism. The present study proves that also estrone is able to emit electrons. Their yield strongly depends on the concentration of the hormone, temperature and on the absorbed energy. The metabolites resulting from this process are likewise able to generate electrons, however with much smaller yields. The formation of the estrone metabolites is studied by HPLC-analyses. In vitro experiments with MCF-7 cells demonstrate the distinct effect of progesterone on the carcinogenity of estrone metabolites. Probable reaction mechanisms for explanation of the observed effects are postulated.


Subject(s)
Electrons , Estradiol/analysis , Estrone/analysis , Progesterone/metabolism , Animals , Cell Line , Chromatography, High Pressure Liquid , Estradiol/metabolism , Estradiol/pharmacology , Estrone/metabolism , Estrone/pharmacology , Mice , Progesterone/analysis , Progesterone/pharmacology
3.
Horm Mol Biol Clin Investig ; 7(1): 303-13, 2011 Oct 01.
Article in English | MEDLINE | ID: mdl-25961268

ABSTRACT

The hormones 17ß-estradiol (17ßE2), 21α-hydroxyprogesterone (21α-HOPRG) and corticosterone (CORT) were used as representative models for the study. As a source for hormone excitation in singlet state serviced monochromatic UV-light (λ=254 nm), it was stated that the transients resulting by e-aq emission in air-free mixture water/ethanol 40/60, as long as they are in "status nascendi", can be regenerated by electron transfer from a potent electron donor, e.g., vitamin C. The hormone regeneration (%) strongly depends, after all, on specific hormone molecular structure, concentration, temperature, etc. Because of the large heterogenic molecular structures, the substrates dissolved in the solvent mixture form "associates" (unstable complexes) in concentrations >109 mol/L hormone. The hormones eject, but they also consume e-aq with a rather high reaction rate constant (k≈109 up to 2×1010 L/mol.s), therefore, they act as "electron mediators". It was also observed that the hormones by dissolution in aerated solvent mixture are sensitive towards oxygen. For an explanation of the results, probable reaction mechanisms are presented. The described method offers a new pathway and possibilities for application in medicine.

4.
In Vivo ; 24(5): 727-33, 2010.
Article in English | MEDLINE | ID: mdl-20952741

ABSTRACT

Based on previous investigations on several hormones, 17α-hydroxyprogesterone (17α-HOPRG) was studied in respect to cancer initiation by its metabolites resulting from electron emission. The emission of electrons (e⁻(aq)) from its singlet excited state of 17α-HOPRG and HPLC-analysis of products were studied. Possible carcinogenicity of metabolites originating from 17α-HOPRG and the effect of progesterone (PRG) in this respect were studied in vitro. The results showed that 17α-HOPRG is very sensitive towards oxygen. The highest Q(e⁻(aq)) values were obtained by dissolution and UV-irradiation of substrate in airfree media. 17α-HOPRG metabolites showed a strong anticancer activity, which is, however, lower compared to that of PRG-metabolites. Mixture of both hormones, 17α-HOPRG and PRG, in respect to carcinogenicity showed a synergistic effect of PRG on 17α-HOPRG. Reaction mechanisms are presented.


Subject(s)
Electrons/therapeutic use , Neoplasms, Radiation-Induced/etiology , Neoplasms/radiotherapy , Progesterone/analogs & derivatives , Progesterone/chemistry , Electrons/adverse effects , Free Radicals/chemistry , Free Radicals/metabolism , Free Radicals/radiation effects , Humans , In Vitro Techniques , Models, Chemical , Oxidation-Reduction , Oxygen/metabolism , Progesterone/metabolism , Progesterone/radiation effects , Ultraviolet Rays/adverse effects , Ultraviolet Therapy/methods
5.
In Vivo ; 24(4): 535-41, 2010.
Article in English | MEDLINE | ID: mdl-20668321

ABSTRACT

BACKGROUND: Based on the different behaviour of 17beta-estradiol (17betaE(2)) and progesterone (PRG), it was of interest to investigate the interaction of both hormones in respect of their electron emission and cytotoxicity by experiments in vitro. MATERIALS AND METHODS: The studies include determination of emitted electrons (e(-)(aq)) by the individual hormones as well as by their mixtures, all complexed with cyclodextrin (HBC). Experiments in vitro (Escherichia coli bacteria) were performed for a better understanding of the mechanisms involved. Survival ratios, DeltaD(37)(Gy), were calculated. RESULTS: Aqueous HBC as well as 17betaE(2) and PRG, individually as well as in mixtures, are able to emit e(-)(aq). The resulting transients can lead to the formation of metabolites, some of which can initiate cancer. It was established that both hormones, 17betaE(2) and PRG, interact in respect to their electron emission property. In the frame of experiments in vitro, it was found that oxidizing radicals (OH, O(2)(-)) lead to negative DeltaD(37)(Gy) values, indicating cytostatic properties. On the other hand, the primary reducing radicals (e(-)(aq), H) lead to positive DeltaD(37)(Gy) values, indicating a radical-scavenging effect. CONCLUSION: The main outcome of this work is that PRG in combination with 17betaE(2) can strongly reduce the number of carcinogenic 17betaE(2)-metabolites. This fact offers a new pathway for application of hormones in medical treatment of patients.


Subject(s)
Cyclodextrins/pharmacology , Estradiol/pharmacology , Free Radicals/metabolism , Progesterone/pharmacology , Aerobiosis , Cell Survival/drug effects , Cell Survival/radiation effects , Electrons , Escherichia coli/cytology , Escherichia coli/drug effects , Escherichia coli/metabolism , Escherichia coli/radiation effects , Estradiol/metabolism , Kinetics , Oxidation-Reduction , Progesterone/metabolism , Ultraviolet Rays
SELECTION OF CITATIONS
SEARCH DETAIL
...