121190 20241125101127.0 doi 10.1016/j.theriogenology.2022.12.022 sideral 131715 ART-2023-131715 eng Miguel-Jiménez, Sara (orcid)0000-0001-6733-9373 In vitro approach points to a chemotactic effect of melatonin on ram spermatozoa 2023 Access copy available to the general public Unrestricted Sperm orientation mechanisms, such as chemotaxis, are essential for the sperm to reach the oocyte and fertilize it. Melatonin is secreted by the cumulus cells and is also present in the follicular fluid in mammals. The presence of membrane receptors for melatonin in ram spermatozoa, and its proven involvement in the sperm functionality, may suggest a possible role in the guided movement towards the oocyte. Hence, the objective of the present work is to study the in vitro potential chemotactic action of melatonin on ram spermatozoa, analysing the influence of the season (breeding and non-breeding) and the sperm capacitation state. The first experimental approach consisted in the inclusion of melatonin in the upper layer of a swim-up selection method. During the non-breeding season, the presence of melatonin at 100 pM and 1 μM concentrations significantly increased the cell recovery rate, and induced changes in the sperm location of the MT2 melatonin receptor, compared with the standard swim-up. Moreover, the selected sperm population with 100 pM melatonin presented a higher percentage of capacitated spermatozoa. The greater recovery rate obtained with melatonin could be due to the stimulation of sperm movement in random directions, i.e., a chemokinetic effect, or due to a guided movement (chemotaxis) towards the gradient of the melatonin. To elucidate this issue, together with the study of the influence of the sperm capacitation status, we performed a second experimental approach which consisted in the use of chemotaxis chambers and an open-source software (Open-CASA) that analyses the sperm trajectories towards the hormone gradient and calculates a chemotaxis index (SL index). There was a significant difference between the SL index in the presence of 1 μM melatonin and the control without hormone. This effect was only observed in capacitated spermatozoa with cAMP-elevating agents (Cap-CK samples) obtained during the non-breeding season. These results would point to an in vitro chemotactic effect of melatonin on ram spermatozoa, although chemokinesis cannot be ruled out. Nonetheless, the inclusion of this hormone in the swim-up procedure could enhance the sperm recovery rate. info:eu-repo/grantAgreement/ES/DGA/A07-20R info:eu-repo/grantAgreement/ES/MINECO/AGL2017-83799-R info:eu-repo/semantics/openAccess by http://creativecommons.org/licenses/by/3.0/es/ 2.4 2023 VETERINARY SCIENCES 24 / 167 = 0.144 2023 Q1 T1 REPRODUCTIVE BIOLOGY 22 / 39 = 0.564 2023 Q3 T2 0.738 2023 Animal Science and Zoology 2023 Q1 Small Animals 2023 Q1 Food Animals 2023 Q1 Equine 2023 Q1 5.5 2023 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Borao, Sonia Portolés-Bayod, Virginia Casao, Adriana Universidad de Zaragoza (orcid)0000-0003-1997-4262 Pérez-Pe, Rosaura Universidad de Zaragoza (orcid)0000-0002-2312-6402 1002 819 Universidad de Zaragoza Dpto. Bioq.Biolog.Mol. Celular Área Zoología 198 (2023), 36-46 1879-3231] THERIOGENOLOGY 0093-691X 1995747 http://zaguan.unizar.es/record/121190/files/texto_completo.pdf Versión publicada 2521369 http://zaguan.unizar.es/record/121190/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:121190 articulos driver 2024-11-22-11:57:50 ARTICLE