Degradation of Extracellular DNA by DNase1 Significantly Reduces Testicular Damage After Testicular Torsion in Rats

Abstract

To examine the effects of DNase1 treatment on testicular damage after testicular torsion (TT). It has been demonstrated that TT induces thrombus formation and that anticoagulation significantly reduces testicular damage after TT. It was hypothesized that these thrombi are dependent on neutrophil extracellular traps (NETs) and thus NETs disintegration would reduce testicular cell damage. A sham operation was performed in 10 rats. Thirty-four rats underwent induction of iatrogenic TT for 3 hours. After de-torsion and randomization, 24 rats received DNase1 or inactivated DNase1. The following parameters were assessed: testicular damage via Cosentino grading; spermatogenesis via Johnsen score; stem cell factor and c-Kit, apoptosis via Bax, Bcl2, Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling assay, and cleaved caspase3 staining; oxidative stress via superoxide dismutase, catalase, glutathione peroxidase, and malondialdehyde; neutrophil recruitment via myeloperoxidase and neutrophil elastase staining; and NET formation via cell-free DNA. Forty-three rats were included in the study. Subjects treated with DNase1 showed significantly less cellular damage, oxidative stress, and apoptosis. Further, DNase1-treated rats demonstrated a significant improvement of spermatogenesis, compared with the controls. The results of the study indicate that thrombus formation during TT is quite likely NET associated, and that dissolution of cell-free DNA (including NETs) significantly improves testicular damage in rats. As treatment with DNase1 reduced apoptosis, oxidative stress, and inflammation, without adversely affecting coagulation, it might be a suitable treatment for (neonatal) TT and ought to be evaluated in humans.