P-106 The inhibition of sperm SIRT1 enhances fertilization and modifies subsequent embryonic epigenetic quality

Abstract Study question Is SIRT1 present in sperm and thus involved fertilization and/or epigenetic code? Do the SIRT1-driven marks be transmitted to progeny? Summary answer localized at head influences code via its deacetylation activity. SIRT1-modulated epigenome is zygotes blastocysts. What known already The addition or removal of acetyl group from lysine residua (i.e. acetylation) post-translationally modulates proteins through action acetylases deacetylases, respectively. (also Sirtuin 1) capable deacetylate a number proteins, including histones, with roles male reproduction. Testicular deficit leads subfertility increases abnormal immotile spermatozoa that fail fertilize. However, neither presence nor function has been investigated despite significance acetylation events around fertilization. Moreover, mode highlights relevance for success pre-implantation embryo. design, size, duration Mouse 14-18-weeks-old males CD-1 x C57Bl6 hybrid strain were isolated epididymis. Sperm incubated under capacitating conditions sirtinol (5 µM), selective inhibitor, vehicle (0.1% v/v DMSO) 1 h 37 °C 5% CO2. Participants/materials, setting, methods Motility acrosome reaction was evaluated as previously stated (Ritagliati et al., 2018). extracted into RIPA-buffer acetylated depicted by western blot. Finally, vitro embryo culture performed. Above parameters defining IVF outcomes (i.e., fertilization, cleavage, blastocyst rate), immunocytochemistry histone 4 16th (H4K16) quantified. Main results role chance head, apparently perinuclear theca perforatorium. Inhibition increase (2.28 vs 1, fold change values) hyperactivation (16.55 ± 0.79 10.84 %sperm), enhanced motility facilitates penetrate oocyte, well (28.69 0.41 17.98 %sperm). Subsequently, these able better fertilize oocytes (90.5 7.21 66.25 7.21, %). Interestingly, derived sirtinol-pre-treated developed 2-cell embryos higher rate than those fertilized untreated (79.33 67.00 we observed significant hyperacetylation H4K16 pronuclei sirtinol-treated (8.19 1.02 6.10 2.09 45.55 13.96 27.62 13.96, integrated density signals, respectively). Limitations, reasons caution Although accumulated pronuclei, do not know which subset genes affected. Therefore, only can assure are offspring, but their consequences should further elucidated. For knowledge transfer humans, verification study required. Wider implications findings reduction testicular expression an age-related phenomenon. our support basis new interventions against infertility. due high reactivity inactivation, becomes target pharmacologically enhance ability assisted reproductive techniques. Trial registration Animal procedures conducted accordance Act No. 246/1992 Coll. on Protection Animals Against Cruelty supervision Welfare Committee Ministry Education, Youth Sports Czech Republic, approval ID MSMT-11925/2016-3.