20.500.12556/DiRROS-29963 Effects of slow freezing and vitrification of human semen on post-thaw semen quality and miRNA expression Semen cryopreservation has played an important role in medically assisted reproduction for decades. In addition to preserving male fertility, it is sometimes used for overcoming logistical issues. Despite its proven clinical usability and safety, there is a lack of knowledge of how it affects spermatozoa at the molecular level, especially in terms of non-coding RNAs. Therefore, we conducted this study, where we compared slow freezing and vitrification of good- and poor-quality human semen samples by analyzing conventional sperm quality parameters, performing functional tests and analyzing the expression of miRNAs. The results revealed that cryopreservation of normozoospermic samples does not alter the maturity of spermatozoa (protamine staining, hyaluronan binding), although cryopreservation can increase sperm DNA fragmentation and lower motility. On a molecular level, we revealed that in both types of cryopreservation, miRNAs from spermatozoa are significantly overexpressed compared to those in the native semen of normozoospermic patients, but in oligozoospermic samples, this effect is observed only after vitrification. Moreover, we show that expression of selected miRNAs is mostly overexpressed in native oligozoospermic samples compared to normozoospermic samples. Conversely, when vitrified normozoospermic and oligozoospermic samples were compared, we determined that only miR-99b-5p was significantly overexpressed in oligozoospermic sperm samples, and when comparing slow freezing, only miR-15b-5p and miR-34b3p were significantly under-expressed in oligozoospermic sperm samples. Therefore, our results imply that cryopreservation of normozoospermic sperm samples can modulate miRNA expression profiles in spermatozoa to become comparable to those in oligozoospermic samples. semen cryopreservation vitrification slow freezing spermatozoa microRNA assisted reproduction infertility seme kriokonzervacija vitrifikacija počasno zamrzovanje semenčice mikroRNA asistirana reprodukcija neplodnost true false true Angleški jezik Slovenski jezik Neznano 2026-06-10 12:54:44 2026-06-10 12:54:45 2026-06-11 03:47:36 0000-00-00 00:00:00 2024 0 0 Nasl. z nasl. zaslona; Opis vira z dne 9. 4. 2024; str. 1-23 iss. 8, [article no.] 4157 Vol. 25 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 61 1422-0067 10.3390/ijms25084157 191979267 RAZ_Podgrajsek_Rebeka_2024.pdf RAZ_Podgrajsek_Rebeka_2024.pdf 1 022FB9FEB5D4336B73887CCBF23A432B d4ff3a09de454d4327ade6cf1105e3a3de5e1b5cba1804998d62d40d145956de edd00391-64ba-11f1-9215-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=45131 https://www.mdpi.com/1422-0067/25/8/4157 1 cbe14aca-64ba-11f1-9215-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=45130 Univerzitetni klinični center Ljubljana 0 0 0