Year: 2007
Type: dissertation
Study design: Observational Study
Abstract: Male fertility has for many years been defined in vitro as the ability of sperm to fertilize oocytes and to obtain early cleavage-stage embryos.Spermatozoa comprise of an extraordinary high percentage of polyunsaturated fatty acids in their plasma membrane.Due to an extremely low content of cytoplasm, sperm cells have a particularly low potential to scavenge reactive oxygen species (ROS), and are therefore highly sensitive to oxidative processes, which lead to sperm nucleus DNA damage/fragmentation.Normally, DNA fragmentation occurs in every ejaculate and can be induced by an excessive ROS production of active leukocytes or the spermatozoa themselves.Under distressed conditions, DNA fragmentation may also occur in the testis as a result of oxidative processes in the apoptotic cascade.These DNA fragmentations can be regarded as late signs of programmed cell death (apoptosis).Clinically, DNA fragmentation in spermatozoa results in significantly decreased implantation and pregnancy rates especially in patients with oligo-and/or teratozoospermia.The p-pattern normal sperm morphology has been shown to give poorer fertilization rates in vitro than the g-and n-patterns.In this study there is reported on the significant correlation found between the p-pattern normal sperm morphology and sperm DNA fragmentation as measured with the terminal deoxynucleotidyl transferase-mediated dUDP-biotin end labeling (TUNEL) assay.This finding further explains the lower fertility potential of patients presenting with p-pattern normal sperm morphology.In addition, this study explores the intricate relations between ROS in the semen, DNA fragmentation of the spermatozoa, as measured with the TUNEL assay and the sperm chromatin structure assay (SCSA ), spermatozoa apoptotic status and sperm parameters as measured with a standard semen analysis.Positive correlations were found between ROS and the apoptotic status of the sperm, as well as between sperm with non-fragmented DNA and sperm concentration and percentage motility.The results emphasize the importance of sperm selection especially when the treatment of choice is intracytoplasmic sperm injection (ICSI).
Author: Christiaan F. Hoogendijk
Language: English
Subfield: Reproductive Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
Award: G8140326150
OpenAlex ID: W2133466596