Higher Sperm DNA Damage in Semen From Men With Spinal Cord Injuries Compared With Controls

Abstract

Semen from men with spinal cord injuries (SCI) and control subjects was investigated for sperm DNA damage using the sperm chromatin structure assay. Three experiments were performed. In experiment 1, the DNA fragmentation index (DFI) was compared in semen from SCI subjects and control subjects. In experiment 2, the % DFI was determined in repeated ejaculations to examine the effect of anejaculation on DFI. In experiment 3, the DFI was determined in neat vs processed semen to examine the effect of necrospermia or leukocytospermia on DFI. The results of experiment 1 showed a significantly higher mean (6 SEM) DFI in the semen of SCI subjects (65.2% 6 6.6%; range, 42.3%-90.8%) compared with control subjects (15.4% 6 2.9%; range, 5.4%-33.5%; P , .001). In experiment 2, there was a high correlation between the DFIs obtained in the first semen specimens and the DFIs obtained 3 days later in semen of the same SCI subjects (r s 5 .94; P , .02). In experiment 3, the results showed no significant difference between mean DFI in aliquots of neat semen (79.3% 6 9.9%) vs matched aliquots of semen processed to remove dead sperm and leukocytes in SCI subjects (75.2% 6 16.1%). The DFI is higher in semen from men with SCI vs controls. The cause of this condition is unknown but does not seem to be due to prolonged anejaculation or to the proximate conditions of necrospermia or leukocytospermia. The relevance of these findings to fertility outcomes with SCI male partners remains to be determined.

Comparison of in vitro fertilization/intracytoplasmic sperm injection outcomes in male factor infertility patients with and without spinal cord injuries

“…The most common abnormalities include low sperm motility, low sperm viability, leukocytospermia, and high sperm DNA fragmentation (3)(4)(5)(6)11). Although the cause of these semen abnormalities is unknown, there is evidence that inflammatory processes in the semen contribute to the problem (12)(13)(14).…”

“…Most have semen with normal sperm concentration, but abnormally low sperm motility and viability. Leukocytospermia and high sperm DNA fragmentation are also frequent semen characteristics in this population (3)(4)(5)(6). This particular semen profile of men with SCI is uncommon in the general male factor infertility population.…”

Fresh testicular sperm retrieved from men with spinal cord injury retains equal fecundity to that from men with obstructive azoospermia via intracytoplasmic sperm injection

“…It has been reported that some disruption of neural input to the testis may be responsible for the reduced spermatogenesis (14). Recently, higher sperm DNA damage in semen from men with SCI has been reported (15).…”

Sperm chromatin condensation, DNA integrity, and apoptosis in men with spinal cord injury

“…In another study, the DNA fragmentation index was higher in semen samples from men with SCI in comparison with controls. 46 Our previous study on SCI rats demonstrated that chronic cord injury alters the stability of sperm chromatin by influencing the epididymal phase of chromatin condensation and disulfide bond formation, but histone-protamine replacement phase may remain intact. 11 Alteration of normal epididymal activity following SCI disturbs sperm nuclear maturation.…”