The purpose of the current study was to analyze phenotypic and functional characteristics of common carp (Cyprinus carpio) spermatozoa during in vitro aging and to investigate whether global DNA methylation is affected by sperm aging. Milt was collected from five individual males, stored in vitro on ice in a refrigerator for up to 96 h post stripping (HPS) and used to fertilize eggs with intervals of 1, 24 and 96 h. Computer-assisted sperm analysis and a S3e Cell Sorter was employed to determine the spermatozoa phenotypic characteristics (motility, velocity, concentration and viability). In addition, pH and osmolality of the seminal fluid and the capacity of the spermatozoa to fertilize, hatching rate and health of the resulting embryos were examined at different aging times. Whole-genome bisulfite sequencing was used to compare the global and gene-specific DNA methylation in fresh and aged spermatozoa. The results demonstrated that spermatozoa aging in common carp significantly affects their performance and thus the success of artificial fertilization. The methylation level at the cytosine-phosphate-guanine (CpG) sites increased significantly with 24 HPS spermatozoa compared to the fresh group at 1 HPS and then decreased significantly at 96 HPS. A more detailed investigation of gene specific differences in the DNA methylation was hindered by incomplete annotation of the C. carpio genome in the public databases.

• Keywords
• DNA methylation, common carp, epigenetics, fertilization, fish, milt, sperm aging, sperm quality, sperm storage,
• MeSH
• Carps genetics   growth & development   MeSH
• DNA Methylation genetics   MeSH
• Spermatozoa metabolism   pathology   MeSH
• Aging genetics   pathology   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

The protective influence of seminal plasma and the antioxidants catalase (CAT), superoxide dismutase (SOD), and glutathione (GTH) on quality parameters, oxidative stress indices, and antioxidant activity was studied in common carp (Cyprinus carpio) spermatozoa exposed to the xanthine-xanthine oxidase (X-XO) system. Fish spermatozoa were incubated for 5 and 20 min at 4 °C with X-XO concentrations of 1 mM X-0.1 U/mL, 0.6 mM X-0.05 U/mL, 0.3 mM X-0.025 U/mL, and 0.1 mM X-0.0125 U/mL. A dose-dependent reduction in spermatozoa motility and velocity was observed at concentrations of 0.1 mM X-0.0125 U/mL to 1 mM X-0.1 U/mL XO. Increase in spermatozoa motility parameters was recorded following treatment with antioxidants and seminal plasma. The level of the oxidative stress indices lipid peroxidation (LPO) and carbonyl derivatives of proteins (CP) was significantly reduced after addition of CAT, SOD, or GTH along with seminal plasma. Significant differences in SOD, glutathione reductase, and glutathione peroxidase activity were seen in spermatozoa incubated with, compared to that without, seminal plasma at all studied X-XO concentrations. The data demonstrated that CAT, SOD, or GTH in combination with SP can reduce reactive oxygen species stress in fish spermatozoa and improve spermatozoa quality.

• MeSH
• Antioxidants metabolism   MeSH
• Glutathione Reductase MeSH
• Carps physiology   MeSH
• Sperm Motility physiology   MeSH
• Oxidative Stress physiology   MeSH
• Semen physiology   MeSH
• Spermatozoa physiology   MeSH
• Xanthine metabolism   MeSH
• Xanthine Oxidase metabolism   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Antioxidants MeSH
• Glutathione Reductase MeSH
• Xanthine MeSH
• Xanthine Oxidase MeSH