RESUMO
According to the World Health Organization (WHO), oxidative stress (OS) is a significant contributor to male infertility. Seminal OS can be measured by a number of assays, all of which are either costly or time sensitive and/or require large semen volume and complex instrumentation. One less expensive alternative is to quantify the oxidation-reduction potential (ORP) with the MiOXSYS. In this international multi-center study, we assessed whether ORP levels measured by the MiOXSYS could distinguish semen samples that fall within the 2010 WHO normal reference values from those that do not. Semen samples were collected from 2092 patients in 9 countries; ORP was normalized to sperm concentration (mV/106 sperm/ml). Only those samples with a concentration >1 × 106 sperm ml-1 were included. The results showed that 199 samples fell within the WHO normal reference range while the remaining 1893 samples did not meet one or more of the criteria. ORP was negatively correlated with all semen parameters (P < 0.01) except volume. The area under the curve for ORP was 0.765. The ORP cut-off value (1.34 mV/106 sperm/ml) was able to differentiate specimens with abnormal semen parameters with 98.1% sensitivity, 40.6% specificity, 94.7% positive predictive value (PPV) and 66.6% negative predictive value (NPV). When used as an adjunct to traditional semen analysis, ORP levels may help identify altered functional status of spermatozoa caused by OS in cases of idiopathic male infertility and in male partners of couples suffering recurrent pregnancy loss, and thereby directing these men to relevant medical therapies and lifestyle modifications.
Assuntos
Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Área Sob a Curva , Infertilidade Masculina/metabolismo , Oxirredução , Estresse Oxidativo , Curva ROC , Valores de Referência , Sêmen/metabolismo , Análise do Sêmen/normas , Sensibilidade e Especificidade , Contagem de Espermatozoides/normas , Espermatozoides/metabolismoRESUMO
Background: The aim of the study was to assess the effect of four repeated ejaculationson the same day at two-hour intervals on conventional and functional semenparameters
Methods: Three healthy men [32 +/- 3.6 years] donated the first semen samples after 3-4 days of sexual abstinence followed by three subsequent samples on the same day attwo-hour interval each. Semen samples were processed and analyzed according tothe World Health Organization [WHO] 2010 guidelines. Furthermore, intracellularreactive oxygen [ROS] production, sperm DNA fragmentation and mitochondrialfunction were evaluated by flow cytometry
Results: An overall decreasing trend was noted in the conventional semen parametersat second, third and fourth evaluations after two hours of abstinence in comparisonto first evaluation after 3-4 days of abstinence. The statistical comparison of theconventional semen parameters at fourth evaluation after 2 hr of abstinence revealedsignificant reduction [p<0.05] in the parameters of concentration, total sperm countand total motile sperm count at fourth evaluation. The functional parameter of intracellularROS production showed a decreasing trend with each subsequent evaluation,the difference being significant [p<0.05] at fourth evaluation in comparison to firstevaluation. An increasing trend was noted for DNA fragmentation index [DFI], althoughit remained within acceptable levels [<29%]. The [delta][psi]m[high]spermatozoa andthe integrity of the plasma membrane remained stable throughout the evaluations
Conclusion: The findings of the present study indicate the potential use of additionalsemen samples with repeated ejaculations at short abstinence times in assisted reproductionprocedures particularly from severe oligospermic men