Oxidative Stress Is Associated with Telomere Interaction Impairment and Chromatin Condensation Defects in Spermatozoa of Infertile Males

Abstract

Telomere length can be influenced by reactive oxygen species (ROS) generated by lifestyle factors or environmental exposure. We sought to determine whether oxidative stress has an impact on sperm nuclear alterations, especially on chromatin organization and telomere interactions in the spermatozoa of infertile males. We performed an observational and prospective study including fifty-two males, allocated in the “case group” (30 infertile males presenting conventional semen parameter alterations) and the “control group” (22 males with normal conventional semen parameters). ROS detection was determined on spermatozoa using CellROX© probes. Sperm nuclear damage was assessed using quantitative fluorescence in situ hybridization (Q-FISH) for relative telomere length and telomere number, aniline blue staining for chromatin condensation, terminal deoxynucleotidyl transferase dUTP nick-end labeling for DNA fragmentation, and FISH for aneuploidy and 8-hydroxy-2′-deoxyguanosine immunostaining for oxidative DNA damages. Infertile males had significantly increased levels of cytoplasmic ROS and chromatin condensation defects as well as a higher mean number of telomere signals per spermatozoon in comparison with controls. In addition, the mean number of sperm telomere signals were positively correlated with the percentage of spermatozoa with chromatin condensation defect. In infertile males with conventional semen parameter alterations, oxidative stress is associated with telomere interaction impairment and chromatin condensation defects.

Kastor and Polluks polypeptides encoded by a single gene locus cooperatively regulate VDAC and spermatogenesis

“…8j ). In addition, neither ROS formation, as determined with the use of CellROX Orange 44 , 45 , nor apoptosis was significantly altered in mature spermatozoa or the testis of dKO or VDAC3 KO mice compared with those of WT mice (Fig. 8k–m , and Supplementary Fig.…”

Association between sperm mitochondrial DNA copy number and deletion rate and industrial air pollution dynamics

“…ROS generated by mitochondrial lipid peroxidation play an important role in sperm physiology and function by inducing sperm hyperactivation, capacitation, the acrosome reaction and binding to the zona pellucida 42 . Nevertheless, increased ROS formation and oxidative stress negatively influence sperm chromatin condensation during maturation, impair sperm motility and viability, and induce DNA damage 42 – 47 . This and the previously reported association between mtDNAcn and ROS levels 45 can explain the correlations between mtDNAcn and semen parameters, abnormal chromatin condensation (HDS rate), nuclear DNA fragmentation (DFI), and mtDNAdel rates in our study.…”

Relationships of Telomere Homeostasis with Oxidative Stress and Cardiac Dysfunction in Human Ischaemic Hearts

“…Specifically, dysregulation of structural elements of the telomere, such as the shelterin complex, has been related to telomere alterations [ 11 ]. On the other hand, increases in ROS in the cells are directly related to persistent DNA damage at the telomere regions [ 13 ], as well as a close relationship between oxidative stress mechanisms and the state of telomeres has been observed [ 27 , 28 ]. In addition, oxidative stress plays an important role in the pathophysiology of ICM [ 29 ].…”