Introduction: Dehydroepiandrosterone (DHEA) is an important endogenous steroid hormone with a broad range of biological effects. DHEA is synthetized in the adrenals, gonads, and various neural cells including brain. It is further metabolized to its 7-oxygenated derivatives, which are together with their precursor considered neuroactive steroids. They play a role in the regulation of emotional responses, memory functions and neuronal excitability. The reaction between 7-oxygenated derivatives is catalyzed by 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) which is also responsible for the interconversion between cortisone and cortisol.
Objective: The aim of the study was to develop the liquid chromatography-tandem mass spectrometry method for determination of cortisol, cortisone, DHEA, 7α-OH-DHEA, 7β-OH-DHEA and 7-oxo-DHEA in human plasma, and compare it´s concentrations in healthy men and men with diagnosis of oligospermia or asthenospermia.
Material and methods: We used extraction step (diethyl ether) and derivatization step (2-hydrazino-pyridine) before injecting to the LC-MS/MS. Different chromatographic conditions and parameters of MS/MS detector for each analyte were tested.
Results and discussion: After optimalization of all parameters we can measure all above mentioned steroids from 500µl of plasma. Levels of 7-oxo-DHEA were significantly lower (p<0.05) in men with oligospermia or asthenospermia (n=16) in comparison with healthy men (n=20) and similar trend was observed in 7β-OH-DHEA levels. Cortisone competes for the binding site on the enzyme with 7-oxo-DHEA and it seems that in oligospermic and asthenospermic men cortisone occupies the most of the binding sites on the 11βHSD. Conclusion: The developed method enables rapid and accurate determination of above mentioned steroids in serum. Men with oligospermia or asthenospermia have lower concentrations of 7-oxo-DHEA which has neuroprotective and antiglucorticoid effects.Acknowledgement: Project was supported by IGA MZCR NT/13369, NT/12349 and NT/11513 of Czech Ministry of Health.