The Role of Seminal Oxidative Stress Scavenging System in the Pathogenesis of Sperm DNA Damage in Men Exposed and Not Exposed to Genital Heat Stress.

Responding to the need for the verification of some experimental animal studies showing the involvement of oxidative stress in germ cell damage in the heat-induced testis, we investigated the possibility of a direct relationship between seminal oxidative stress markers (total antioxidant capacity, catalase activity, superoxide dismutase activity, and malondialdehyde concentration) and ejaculated sperm chromatin/DNA integrity (DNA fragmentation and chromatin condensation abnormalities) in distinct groups of men exposed and not exposed to prolonged scrotal hyperthermia. A statistical increase in the proportion of sperm with DNA fragmentation was observed in all the studied subgroups compared to the fertile men. In turn, the groups subjected to heat stress as professional drivers or infertile men with varicocele presented greater disturbances in the oxidative stress scavenging system than men not exposed to genital heat stress. Based on the comparative analysis of the studied parameters, we can conclude that alterations in the seminal oxidative stress scavenging system are directly engaged in the pathogenesis of ejaculated sperm DNA damage regardless of the intensity of the impact of thermal insult. To the best of our knowledge, this study, for the first time, revealed the co-existence of oxidative stress and sperm DNA damage in the semen of professional drivers.

Seminal Plasma Analysis of Oxidative Stress in Different Genitourinary Topographical Regions Involved in Reproductive Tract Disorders Associated with Genital Heat Stress.

The pathophysiological mechanisms responsible for male subfertility/infertility caused by or complicated by genital heat stress remains unclear in many respects. Because seminal plasma creates the environment for the proper functioning of spermatozoa, in this study, we verified the associations among standard spermiograms, seminal biochemical parameters (neutral alpha-glucosidase, fructose, and citric acid) and oxidative stress markers (total antioxidant capacity, catalase activity, superoxide dismutase activity, and malondialdehyde concentration) in distinct entities associated with male infertility with and without long-time exposure to local hyperthermia. We demonstrated that men exposed to prolonged environmental or clinically recognized local heat stress in adulthood may suffer from dysregulation of seminal antioxidant components, which can be directly associated with epididymal and prostate function. The comparative analysis of the studied parameters showed numerous correlations among all biochemical parameters (particularly neutral alpha-glucosidase) with low standard semen quality in almost all the investigated infertile groups. In light of the data obtained in this originally designed study, we conclude that more attention should be paid to the epididymis and accessory gland function in subfertile and infertile men exposed to genital heat stress, especially in the context of novel treatment algorithms (targeted therapies).

Killer cell immunoglobulin-like receptor gene association with cryptorchidism.

Cryptorchidism is a condition where a testis persists in the abdominal cavity. Thus, due to elevated temperature we may expect induction of aberrant immune reactions depending on genetic constitution of individual. This may be reflected by development of anti-sperm antibodies (ASA) in cryptorchid males. Also, natural killer (NK) cells which belong to innate immunity may control adaptive immunity. Therefore, the gene system encoding polymorphic NK cell immunoglobulin receptors (KIRs) has been studied. 109 prepubertal boys with cryptorchidism and 136 ethnically matched young male donors were selected to study NK cell KIRs. DNA was isolated using automatic Maxwell(®) system from the peripheral venous blood drawn onto anticoagulant. Olerup SSP KIR Genotyping kit including Taq polymerase was used for detection of KIR genes. Human leukocyte antigen-C (HLA-C) groups, C1 and C2 were established using a Olerup SSP KIR HLA Ligand kit. KIR2DL2 (killer immunoglobulin-like receptor two-domain long 2) and KIR2DS2 (killer immunoglobulin-like receptor two-domain short 2) genes were less frequent in patients than in control individuals (corrected p values: 0.0110 and 0.0383, respectively). However, no significant differences were observed between ASA-positive and ASA-negative patients, or between bilateral or unilateral cryptorchidism. No association between KIR ligands C1 and C2, alone or together with KIR2DL2, was found. However, the results suggest that KIR2DL2+/KIR2DS2+ genotype may be, to some extent, protective against cryptorchidism.