High DNA stainability in the SCSA® is associated with poor embryo development and lower implantation rate

Background: The Sperm Chromatin Structure Assay (SCSA®), in addition to identifying the DNA Fragmentation Index (DFI) also identifies High DNA satiability (HDS), supposed to reflect the nuclear compaction of spermatozoa. However, data on what exactly this parameter reveals, its relevance and usefulness are contradictory. In order to shed light on this situation, spermatozoa of a cohort (N = 397) of infertile men were subjected to the SCSA®, TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling) and CMA3 (Chromomycin A3) tests. In a smaller subcohort (N = 100), aniline blue (AB) and toluidine blue (TB) staining were performed in addition. The objective of this study was thus to answer the question of whether HDS is a relevant and reliable parameter to be taken into account? Results: HDS does not appear to be a reliable indicator of nuclear immaturity because it shows a weak correlation with the CMA3, AB and TB stains. The low correlation of HDS with sperm DNA fragmentation (TUNEL and SCSA®) and DNA condensation (CMA3, AB and TB) tests suggests that these two parameters could be decoupled. Unlike DFI and TUNEL, HDS has not been shown to correlate with classic clinical situations of male infertility (asthenozoospermia, teratozoospermia or astheno-teratozoospermia). Conclusion: HDS correlates poorly with most tests that focus specifically on the level of maturity of the sperm nucleus. To our knowledge, this study is the first to compare SCSA®, TUNEL, AB, TB and CMA3 assays on identical samples. It shows the potency, consistency and limitations of each test and the care that must be taken in their interpretation.

Section: Discussionsupporting

confidence: 67%

Could high DNA stainability (HDS) be a valuable indicator of sperm nuclear integrity?

Mohammadi

Tavalaee

Gharagozloo

et al. 2020

“…This suggests that overall, there is no significant change in sperm nuclear condensation/compaction during aging, as HDS is assumed to reflect the level of sperm nuclear protamination [ 51 , 52 ]. Given that a high HDS value has been associated with poor embryo development and lower implantation rate [ 76 , 77 ], events also associated with defective sperm cells during aging, it is interesting that impaired nuclear condensation does not appear to be the primary cause of defective spermatozoa associated with aging in our cohort. Given that we observed that sperm DFI increases significantly with aging, one could extrapolate that loss of sperm nuclear integrity with aging is more associated with direct DNA strand breaks than with lower nuclear compaction.…”

Section: Discussionmentioning

confidence: 98%

Sperm chromatin structure assay (SCSA®) and flow cytometry-assisted TUNEL assay provide a concordant assessment of sperm DNA fragmentation as a function of age in a large cohort of approximately 10,000 patients

Behdarvandian,

Nasr-Esfahani,

Tavalaee

et al. 2023

Background Sperm DNA integrity is increasingly seen as a critical characteristic determining reproductive success, both in natural reproduction and in assisted reproductive technologies (ART). Despite this awareness, sperm DNA and nuclear integrity tests are still not part of routine examinations for either infertile men or fertile men wishing to assess their reproductive capacity. This is not due to the unavailability of DNA and sperm nuclear integrity tests. On the contrary, several relevant but distinct tests are available and have been used in many clinical trials, which has led to conflicting results and confusion. The reasons for this are mainly the lack of standardization between different clinics and between the tests themselves. In addition, the small number of samples analyzed in these trials has often weakened the value of the analyses performed. In the present work, we used a large cohort of semen samples, covering a wide age range, which were simultaneously evaluated for sperm DNA fragmentation (SDF) using two of the most frequently used SDF assays, namely the TUNEL assay and the sperm chromatin structure assay (SCSA®). At the same time, as standard seminal parameters (sperm motility, sperm morphology, sperm count) were available for these samples, correlations between age, SDF and conventional seminal parameters were analyzed. Results We show that the SCSA® and TUNEL assessments of SDF produce concordant data. However, the SDF assessed by TUNEL is systematically lower than that assessed by SCSA®. Regardless of the test used, the SDF increases steadily during aging, while the HDS parameter (High DNA stainability assessed via SCSA®) remains unchanged. In the cohort analyzed, conventional sperm parameters do not seem to discriminate with aging. Only sperm volume and motility were significantly lower in the oldest age group analyzed [50–59 years of age]. Conclusions In the large cohort analyzed, SDF is an age-dependent parameter, increasing linearly with aging. The SCSA® assessment of SDF and the flow cytometry-assisted TUNEL assessment are well correlated, although TUNEL is less sensitive than SCSA®. This difference in sensitivity should be taken into account in the final assessment of the true level of fragmentation of the sperm nucleus of a given sample. The classical sperm parameters (motility, morphology, sperm count) do not change dramatically with age, making them inadequate to assess the fertility potential of an individual.

“…A Danish study found that at %DFI > 20, male’s probability of fathering a child sharply declined [ 19 ]. Additionally, as HDS rises, it is associated with lower implantation rates and delayed/poor embryo development [ 20 ]. HDS > 15% has been associated with poor IVF fertilization rate [ 21 ].…”

Section: Introductionmentioning

confidence: 99%

Effects of alcohol use on sperm chromatin structure, a retrospective analysis

Trautman¹,

Gurumoorthy²,

Hansen³

2023

Background The evaluation of the infertile couple is often complex as multiple factors in both the male and female can contribute, including social history. Previous studies have displayed that male ethanol consumption can disturb sperm motility, nuclear maturity, and deoxyribonucleic acid (DNA) integrity. The main purpose of this study is to evaluate the effects of male alcohol use on sperm chromatin structure analysis (SCSA®). This study was a retrospective chart review of 209 couples that presented to a midsize infertility clinic in the Midwest and had a semen analysis and SCSA® performed. Data extracted from the electronic medical record included demographics, tobacco use, alcohol use, occupational exposures, semen analysis results, and SCSA® results (DNA Fragmentation index (DFI) and High DNA stainability (HDS)). Statistical analysis was performed on this data set to determine significance with a p-level of 0.05, with the primary input being level of alcohol use and primary outcome being the SCSA® parameters. Results Overall, 11% of the cohort had heavy alcohol use (> 10 drinks/week), 27% moderate (3–10/week), 34% rare (0.5- < 3/week), and 28% none. 36% of the cohort had HDS > 10% (a marker of immature sperm chromatin). Level of alcohol use was not significantly associated with HDS > 10% or DFI. Heavier alcohol use was significantly associated with lower sperm count (p = 0.042). Increasing age was significantly associated with increasing DNA Fragmentation Index (p = 0.006), increased sperm count (p = 0.002), and lower semen volume (p = 0.022). Exposure to heat at work was significantly associated with lower semen volume (p = 0.042). Tobacco use was associated with lower sperm motility (p < 0.0001) and lower sperm count (p = 0.002). Conclusions There was not a significant association between the level of alcohol use and the High DNA Stainability or DNA Fragmentation Index of sperm. Increasing age was associated with semen parameters as expected, heat exposure was associated with lower semen volume, and tobacco use was associated with lower sperm motility and density. Further studies could investigate alcohol use and reactive oxidative species in sperm.