Abstract
Vol.41 No.2
- « prev
- ↑Table of Contents
- next »
Original
Effect of Aging on Embryonic Telomere Length and Mitochondrial DNA Content of Bulls
JMOR, 41(2) 79-86, 2024
Mitochondrial quantity in embryos increases during embryonic development; however, the factors underlying this increase remain unclear. We previously demonstrated that embryonic telomere length (TL) is closely associated with mitochondrial DNA (mtDNA) copy number in mouse blastocysts. Furthermore, paternal aging affects both TL and mtDNA copy numbers in blastocysts. In this study, we used frozen-thawed semen derived from a single bull at 18 months (Y-sperm) and 78 months (MA-sperm) of age and examined the TL in sperm, and the TL, and mtDNA copy number, as well as their correlation in blastocyst-stage embryos. The TL in sperm determined by real-time quantitative PCR was shorter in DNA from MA-sperm than in DNA from Y-sperm. Additionally, MA-sperm had lower fertilization ability and developmental competence in blastocyst-stage embryos compared to Y-sperm. The TL of embryos derived from MA-sperm was shorter than that of embryos derived from Y-sperm; however, the mtDNA copy number did not differ between the two groups. Furthermore, a positive correlation between TL and mtDNA copy number was observed in blastocysts derived from Y-sperm. In conclusion, the timing of semen collection influences TL in sperm and subsequent blastocysts.
