Dataset Information

Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction.

ABSTRACT:

Background

Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development. In some mammals, like pigs, ejaculates are emitted in three separate fractions: pre-sperm, sperm-rich (SRF) and post sperm-rich (PSRF). These fractions are known to vary in volume, sperm concentration and quality, as well as in the origin and composition of seminal plasma (SP), with differences being also observed within the SRF one. Yet, whether disparities in the DNA integrity and chromatin condensation and protamination of their sperm exist has not been interrogated.

Results

This study determined chromatin protamination (Chromomycin A3 test, CMA₃), condensation (Dibromobimane test, DBB), and DNA integrity (Comet assay) in the pig sperm contained in the first 10 mL of the SRF (SRF-P1), the remaining portion of the sperm-rich fraction (SRF-P2), and the post sperm-rich fraction (PSRF). While chromatin protamination was found to be similar between the different ejaculate fractions (P > 0.05), chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF (P = 0.018 and P = 0.004, respectively). Regarding DNA integrity, no differences between fractions were observed (P > 0.05). As the SRF-P1 has the highest sperm concentration and ejaculate fractions are known to differ in antioxidant composition, the oxidative stress index (OSi) in SP, calculated as total oxidant activity divided by total antioxidant capacity, was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF (0.42 ± 0.06 vs. 0.23 ± 0.09 and 0.08 ± 0.00, respectively; P < 0.01); this index, in addition, was observed to be correlated to the sperm concentration of each fraction (Rs = 0.973; P < 0.001).

Conclusion

While sperm DNA integrity was not found to differ between ejaculate fractions, SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF. This could be related to the OSi of each fraction.

SUBMITTER: Vinolas-Verges E

PROVIDER: S-EPMC10626759 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction.

Viñolas-Vergés Estel E Ribas-Maynou Jordi J Barranco Isabel I Peres Rubio Camila C Bonet Sergi S Roca Jordi J Yeste Marc M

Journal of animal science and biotechnology 20231106 1

<h4>Background</h4>Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development. In some mammals, like pigs, ejaculates are emitted in three separate fractions: pre-sperm, sperm-rich (SRF) and post sperm-rich (PSRF). These fractions are known to vary in volume, sperm concentration and quality, as well as in the origin and composition of seminal plasma (SP), with differences being also observed within the SRF one. Ye ...[more]

PMID: 37926841

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Dataset Information

Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction.

Background

Results

Conclusion

Publications

Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction.

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