Michaela Králíková

Intraindividual variability of homocysteine and related thiols concentrations in follicular fluid

PurposeTo determine intraindividual variability in concentrations of homocysteine and related thiols in follicular fluids of particular follicles after ovarian stimulation and assess the differences between follicles with/or without oocytes.MethodsHPLC-FD analysis of plasma and follicular fluid cysteine, homocysteine, cysteinylglycine and glutathione in women undergoing IVF.ResultsIn blood plasma, the homocysteine, cysteine, and cysteinylglycine concentrations decreased significantly during stimulation with rec FSH (p < 0.001). We found significant differences in concentrations of cysteine and glutathione between follicles with or without retrieved oocytes. High intraindividual variability in concentrations of thiols was determined.ConclusionsThe concentration variability of thiols between single follicles is very high and we recommend mean at least from 3 follicles with/or without oocytes for characterization of each woman. It is the best to examine individual follicles for further research and analysis of fertility outcomes.

The intracellular concentration of homocysteine and related thiols is negatively correlated to sperm quality after highly effective method of sperm lysis

The aims of this study were to determine concentrations of total homocysteine, cysteine, cysteinylglycine and glutathione in spermatozoa, seminal fluid and blood plasma and to analyse their relationships with sperm parameters. For this reason, a new highly effective method of spermatozoa lysis was developed, using methanol, freezing and subsequent thawing in ultrasonic bath. An HPLC‐FD assay was conducted on thiols concentrations in lysed spermatozoa, seminal fluid and blood plasma. Concentrations of thiols in spermatozoa were significantly lower in men with normozoospermia than in samples with pathological semen parameters. Statistical analysis found significant correlations between thiol concentrations in spermatozoa and semen parameters, while the same analysis with thiol concentrations in seminal fluid was substantially less powerful. Only cysteinylglycine concentrations in seminal fluid significantly correlated with pathological semen parameters. No significant differences or correlations were found with blood plasma concentrations.