Evaluation of sperm DNA fragmentation and chromatin structure in infertile men with immotile short-tail sperm defect

Andrologia. 2020 Feb;52(1):e13445. doi: 10.1111/and.13445. Epub 2019 Oct 28.

Abstract

Teratozoospermia is characterised by the presence of spermatozoa with abnormal morphology. One of the morphological disorders that lead to male infertility is immotile short-tail sperm (ISTS) defect. In this study, we evaluated the levels of chromatin packing and DNA fragmentation in patients with immotile short-tail sperm defect. Semen samples were obtained from 31 infertile men with ISTS as case group and 31 normozoospermic men as a control group. Protamine status was evaluated using chromomycin A3 (CMA3) staining and sperm DNA fragmentation assessed by sperm chromatin structure assay (SCSA) and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick-end labelling (TUNEL). The percentage of positive CMA3 spermatozoa was significantly higher in patients' samples (22.6 ± 6.9) compared with controls (16.3 ± 4.2) (p < .05) and also mean (±SD) of sperm DNA fragmentation was significantly higher in patients compared with controls, as measured by TUNEL assay (10.45 ± 4.60 vs. 7.03 ± 2.86, p < .05) and SCSA (24.80 ± 13.1 vs. 15.2 ± 7.2, p < .05). According to our study, sperm DNA fragmentation and chromatin packing abnormality are significantly higher in the ISTS samples compared with normal samples. A possible explanation for this relationship is that sperm chromatin condensation and sperm flagellum formation occur during the same phase of spermatogenesis.

Keywords: CMA3; DNA integrity; ISTS; SCSA; TUNEL.

MeSH terms

  • Adult
  • Case-Control Studies
  • Chromatin / metabolism*
  • Chromomycin A3 / chemistry
  • DNA Fragmentation*
  • DNA Packaging
  • Fluorescent Dyes / chemistry
  • Humans
  • Male
  • Middle Aged
  • Papanicolaou Test
  • Protamines / metabolism
  • Semen Analysis / methods
  • Sperm Tail / metabolism
  • Sperm Tail / pathology*
  • Teratozoospermia / genetics*
  • Teratozoospermia / pathology
  • Young Adult

Substances

  • Chromatin
  • Fluorescent Dyes
  • Protamines
  • Chromomycin A3