Deoxyribonucleic acid repair and apoptosis in testicular germ cells of aging fertile men: the role of the poly(adenosine diphosphate-ribosyl)ation pathway

Sperm DNA fragmentation: mechanisms of origin, impact on reproductive outcome, and analysis

“…Therefore, when a spermatozoon with normal morphology is microinjected it does not necessarily mean that the genomic quality is also normal. Interestingly, we have recently proposed that the mechanism of apoptosis in spermiogenesis may be less related to that of cell death but more responsible for the process of stripping the cytoplasm in the final stages of sperm maturation (26).…”

Effects of aging on the male reproductive system

“…If left unrepaired, oxidatively damaged paternal DNA may proceed through fertilization into the offspring, causing a variety of diseases in the offspring spermatogenic potential [93]. As the effect of age on sperm DNA single-and double-strand breaks is well documented [94,95], presence of DNA damage repair-associated proteins such as poly(ADP-ribose) polymerase 1 (PARP-1) were also investigated in testicular tissue samples from older men [96]. Statistically significant differences in the expression of DNA repair proteins as well as apoptosis markers, such as active caspase-3 and cleaved PARP-1, were found most markedly in aging spermatocytes.…”

“…Statistically significant differences in the expression of DNA repair proteins as well as apoptosis markers, such as active caspase-3 and cleaved PARP-1, were found most markedly in aging spermatocytes. The immunohistochemical co-existence of DNA repair and apoptotic markers in aging testicular germ cells can be explained by overactivated PARP-1 leading to initiation of apoptosis [96,97]. Membrane translocation of phosphatidyl serine is one of the early apoptotic biomarker and increases with paternal aging (p < 0.01) [87] (Table 4).…”

Mammalian Spermatogenesis, DNA Repair, Poly(ADP-ribose) Turnover: the State of the Art

“…An age-related increase in DNA break repair and apoptosis was also demonstrated in human testicular germ cells. DNA repair markers (PARP-1, PAR, XRCC1, and apoptosisassociated markers (caspase 9, active caspase 3, and cleaved PARP-1) were detected in these cells (El-Domyati et al, 2009). In summary, DNA damage in spermatozoa can be induced by events involving PARP as regulatory factor and occurring within the testis as apoptosis, and remodelling of sperm chromatin during the process of spermiogenesis, or in the post-testicular phase as induced mainly by radical oxygen species (ROS) and nitric oxide (NO), or by endogenous caspases and endonucleases; or by environmental factors.…”