Cryopreservation of human semen has been widely used in preserving fertility. In order to reduce the damage caused by freezing processes, several studies use antioxidant and stimulant substances, but the effectiveness of these substances and their role in functional sperm control is not well established in the literature. In a previous study by the group, it was noted that the addition of 3mM melatonin, a powerful antioxidant, had benefits in sperm quality when added to slow freeze cryopreserved seminal samples when compared to samples without supplementation, however, a dose-response study is still required. Thus, the aim of this study is to analyze the effect of three melatonin concentrations on the quality of cryopreserved post-thawed sperm by slow freezing methods. For this, semen samples will be selected from 80 volunteer patients, 18 to 45 years old, from the routine of the Androscience Laboratory and Department of Urology of the University of São Paulo Hospital das Clínicas, by signing the Informed Consent Term, between January by August 2020. Samples will be cryopreserved by the slow freeze method without supplementation, with 0.01 mM melatonin, 2 mM melatonin and 3 mM melatonin. Seminal counting and motility parameters, analyzed by WHO criteria, evaluation of DNA fragmentation rate, by SCSA® method and the measurement of ractive oxygen species (ROS) levels by the luminescence method, will be performed in all groups. Data will be analyzed by paired ANOVA and one-way analysis of variances with repeated measures, followed by Holm-Sidak post-test, and adopted a 5% alpha.
News published in Agência FAPESP Newsletter about the scholarship: