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Mechanical processing of hyperviscous semen specimens can negatively affect sperm DNA fragmentation
Ana Paula S Kussler1, Anita M Pimentel, Diego D Alcoba
1Programa de Pós-Graduação em Medicina, Ciências Médicas, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Introduction:
The present study compared the DNA fragmentation in human sperm samples with reduced, physiological, and increased viscosity in order to evaluate whether the process used to reduce viscosity (expulsion of semen through a needle and syringe) alters significantly sperm DNA fragmentation.
Methods:
The seminal parameters of semen samples from 123 patients were evaluated and classified according to their viscosity. Samples with increased viscosity were submitted to a process of expulsion of semen through a 10-mL syringe and an 18-gauge (18G) needle to reduce the seminal viscosity. The DNA fragmentation of all samples was analysed using TUNEL assay (Terminal deoxynucleotidyl transferase mediated dUTP Nick-end labelling assay); in samples with increased viscosity, the fragmentation was assessed before and after the process of expulsion with syringe and needle.
Results:
There was no difference in DNA fragmentation between groups with different viscosity (P = 0.857). A significantly increase in sperm DNA fragmentation after expulsion of hyperviscous semen through the syringe was observed (P = 0.035).
Conclusion:
There was no difference in DNA fragmentation rate between samples with reduced, increased and physiological viscosities; however, the physical process of expulsion of semen through a syringe and needle increased sperm DNA fragmentation.
Insights
Semen viscosity does not affect sperm DNA fragmentation. However, expelling viscous semen through a needle and syringe significantly increases DNA fragmentation in human sperm samples.
Area of Science:
- Reproductive Biology
- Andrology
- Spermatozoa Analysis
Background:
- Semen viscosity is a seminal parameter that may influence sperm function.
- The impact of semen viscosity on sperm DNA fragmentation is not fully understood.
- Investigating the effect of viscosity reduction techniques on sperm DNA integrity is crucial for assisted reproductive technologies.
Purpose of the Study:
- To compare sperm DNA fragmentation in human semen samples with varying viscosities (reduced, physiological, increased).
- To evaluate if the mechanical process of reducing semen viscosity alters sperm DNA fragmentation.
Main Methods:
- Semen samples from 123 patients were analyzed for viscosity.
- Hyperviscous samples were processed using a syringe and 18-gauge needle to reduce viscosity.
- Sperm DNA fragmentation was assessed using the TUNEL assay (Terminal deoxynucleotidyl transferase mediated dUTP Nick-end labelling assay).
- Fragmentation was measured before and after mechanical processing in hyperviscous samples.
Main Results:
- No significant difference in sperm DNA fragmentation was found between semen samples with reduced, physiological, or increased viscosity (P = 0.857).
- A significant increase in sperm DNA fragmentation was observed after the mechanical expulsion of hyperviscous semen through a syringe and needle (P = 0.035).
Conclusions:
- Semen viscosity itself does not correlate with sperm DNA fragmentation levels.
- The physical manipulation of semen, specifically expulsion through a syringe and needle, can induce sperm DNA fragmentation.
- Clinicians should be aware that viscosity reduction methods may impact sperm DNA integrity.
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