Dynamic changes in maternal‒zygotic transition (MZT) require complex regulation of zygote formation, maternal transcript decay, embryonic genome activation (EGA), and cell cycle progression. Although these changes are well described, some key regulatory factors are still elusive. Sirtuin-1 (SIRT1), an NAD+-dependent histone deacetylase, is a versatile driver of MZT via its epigenetic and nonepigenetic substrates. This study focused on the dynamics of SIRT1 in early embryos and its contribution to MZT. A conditional SIRT1-deficient knockout mouse model was used, accompanied by porcine and human embryos. Embryos across mammalian species showed the prominent localization of SIRT1 in the nucleus throughout early embryonic development. Accordingly, SIRT1 interacts with histone H4 on lysine K16 (H4K16) in both mouse and human blastocysts. While maternal SIRT1 is dispensable for MZT, at least one allele of embryonic Sirt1 is required for early embryonic development around the time of EGA. This role of SIRT1 is surprisingly mediated via a transcription-independent mode of action.

• Keywords
• Embryo, Embryonic genome activation, Epigenetics, Histone deacetylase, Oocyte, zygote,
• MeSH
• Blastocyst metabolism   MeSH
• Embryo, Mammalian metabolism   MeSH
• Embryonic Development * genetics   MeSH
• Histones metabolism   MeSH
• Humans MeSH
• Mice, Knockout * MeSH
• Mice MeSH
• Swine MeSH
• Sirtuin 1 * metabolism   genetics   MeSH
• Gene Expression Regulation, Developmental MeSH
• Animals MeSH
• Zygote * metabolism   MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Mice MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Histones MeSH
• SIRT1 protein, human MeSH Browser
• Sirt1 protein, mouse MeSH Browser
• Sirtuin 1 * MeSH

In vitro cultivation systems for oocytes and embryos are characterised by increased levels of reactive oxygen species (ROS), which can be balanced by the addition of suitable antioxidants. S-allyl cysteine (SAC) is a sulfur compound naturally occurring in garlic (Allium sativum), which is responsible for its high antioxidant properties. In this study, we demonstrated the capacity of SAC (0.1, 0.5 and 1.0 mM) to reduce levels of ROS in maturing oocytes significantly after 24 (reduced by 90.33, 82.87 and 91.62%, respectively) and 48 h (reduced by 86.35, 94.42 and 99.05%, respectively) cultivation, without leading to a disturbance of the standard course of meiotic maturation. Oocytes matured in the presence of SAC furthermore maintained reduced levels of ROS even 22 h after parthenogenic activation (reduced by 66.33, 61.64 and 57.80%, respectively). In these oocytes we also demonstrated a growth of early embryo cleavage rate (increased by 33.34, 35.00 and 35.00%, respectively). SAC may be a valuable supplement to cultivation media.

• Keywords
• Antioxidant, Garlic, Oocyte, Pigs, S-allyl cysteine,
• Publication type
• Journal Article MeSH

Porcine oocytes that have matured in in vitro conditions undergo the process of aging during prolonged cultivation, which is manifested by spontaneous parthenogenetic activation, lysis or fragmentation of aged oocytes. This study focused on the role of hydrogen sulfide (H2S) in the process of porcine oocyte aging. H2S is a gaseous signaling molecule and is produced endogenously by the enzymes cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (MPST). We demonstrated that H2S-producing enzymes are active in porcine oocytes and that a statistically significant decline in endogenous H2S production occurs during the first day of aging. Inhibition of these enzymes accelerates signs of aging in oocytes and significantly increases the ratio of fragmented oocytes. The presence of exogenous H2S from a donor (Na2S.9H2O) significantly suppressed the manifestations of aging, reversed the effects of inhibitors and resulted in the complete suppression of oocyte fragmentation. Cultivation of aging oocytes in the presence of H2S donor positively affected their subsequent embryonic development following parthenogenetic activation. Although no unambiguous effects of exogenous H2S on MPF and MAPK activities were detected and the intracellular mechanism underlying H2S activity remains unclear, our study clearly demonstrates the role of H2S in the regulation of porcine oocyte aging.

• MeSH
• Cystathionine beta-Synthase metabolism   MeSH
• Cystathionine gamma-Lyase metabolism   MeSH
• Embryo, Mammalian drug effects   MeSH
• Enzyme Inhibitors pharmacology   MeSH
• Embryo Culture Techniques MeSH
• Cells, Cultured MeSH
• Oocytes drug effects   physiology   MeSH
• Parthenogenesis drug effects   MeSH
• Swine MeSH
• Cellular Senescence drug effects   MeSH
• Hydrogen Sulfide metabolism   pharmacology   MeSH
• Sulfurtransferases metabolism   MeSH
• Animals MeSH
• Check Tag
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• 3-mercaptopyruvate sulphurtransferase MeSH Browser
• Cystathionine beta-Synthase MeSH
• Cystathionine gamma-Lyase MeSH
• Enzyme Inhibitors MeSH
• Hydrogen Sulfide MeSH
• Sulfurtransferases MeSH

Hydrogen sulfide (H2S) has been revealed to be a signal molecule with second messenger action in the somatic cells of many tissues, including the reproductive tract. The aim of this study was to address how exogenous H2S acts on the meiotic maturation of porcine oocytes, including key maturation factors such as MPF and MAPK, and cumulus expansion intensity of cumulus-oocyte complexes. We observed that the H2S donor, Na2S, accelerated oocyte in vitro maturation in a dose-dependent manner, following an increase of MPF activity around germinal vesicle breakdown. Concurrently, the H2S donor affected cumulus expansion, monitored by hyaluronic acid production. Our results suggest that the H2S donor influences oocyte maturation and thus also participates in the regulation of cumulus expansion. The exogenous H2S donor apparently affects key signal pathways of oocyte maturation and cumulus expansion, resulting in faster oocyte maturation with little need of cumulus expansion.

• MeSH
• Extracellular Signal-Regulated MAP Kinases metabolism   MeSH
• Maturation-Promoting Factor metabolism   MeSH
• Gasotransmitters pharmacology   MeSH
• Coculture Techniques MeSH
• Cells, Cultured MeSH
• Cumulus Cells cytology   metabolism   MeSH
• Meiosis drug effects   MeSH
• Oocytes cytology   metabolism   MeSH
• Swine MeSH
• Hydrogen Sulfide pharmacology   MeSH
• Sulfides pharmacology   MeSH
• Animals MeSH
• Check Tag
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Extracellular Signal-Regulated MAP Kinases MeSH
• Maturation-Promoting Factor MeSH
• Gasotransmitters MeSH
• sodium sulfide MeSH Browser
• Hydrogen Sulfide MeSH
• Sulfides MeSH