Protamine composition of koala and wombat spermatozoa provides new insights into DNA stability following cryopreservation

2019 ◽  
Vol 31 (10) ◽  
pp. 1558
Author(s):  
S. D. Johnston ◽  
C. López-Fernández ◽  
F. Arroyo ◽  
R. Roy ◽  
W. V. Holt ◽  
...  

To investigate differences in the post-thaw DNA stability of koala and wombat spermatozoa, protamine amino acid sequences were compared and it was found that there were three more arginine residues for the wombat. Koala and wombat spermatozoa, cryopreserved using identical protocols, were examined for changes in sperm DNA fragmentation (SDF) dynamics over 24h of post-thaw incubation. Following validation of a wombat sperm chromatin dispersion test, wombat DNA showed a rate of SDF that was 6-fold higher than for koala spermatozoa (P=0.038). Finally, we examined whether expected differences in chromatin compactness, associated with protamine sequence, had an effect on restriction site accessibility of sperm DNA. Thawed spermatozoa were exposed to Alu I and EcoR1 endonuclease restriction enzymes and the SDF dynamics were observed. Koala spermatozoa exposed to Alu I showed a greater rate of SDF (P=0.01), whereas wombat spermatozoa exposed to EcoR1 showed a greater rate of SDF (P=0.032). We conclude that restriction sites in these species are differentially present or exposed and potentially account for differences in SDF dynamics. Although differences in the arginine composition of protamine may explain relative differences in SDF following cryopreservation, they do not support the hypothesis that increased arginine composition increases DNA stability; rather, increased arginine composition in the wombat may reduce post-thaw chromatin swelling.


2017 ◽  
Vol 29 (3) ◽  
pp. 630 ◽  
Author(s):  
S. D. Johnston ◽  
C. López-Fernández ◽  
F. Arroyo ◽  
J. L. Fernández ◽  
J. Gosálvez

Herein we report a method of assessing DNA fragmentation in the saltwater crocodile using the sperm chromatin dispersion test (SCDt) after including frozen–thawed spermatozoa in a microgel (Halomax; Halotech DNA, Madrid, Spain). Following controlled protein depletion, which included a reducing agent, sperm nuclei with fragmented DNA showed a homogeneous and larger halo of chromatin dispersion with a corresponding reduced nucleoid core compared with sperm with non-fragmented DNA. The presence of DNA damage was confirmed directly by incorporation of modified nucleotides using in situ nick translation (ISNT) and indirectly by studying the correlation of the SCDt with the results of DNA damage visualisation using a two-tailed comet assay (r = 0.90; P = 0.037). Results of the SCDt immediately following thawing and after 5 h incubation at 37°C in order to induce a range of DNA damage revealed individual crocodile differences in both the baseline level of DNA damage and DNA longevity.



2020 ◽  
Vol 21 (14) ◽  
pp. 5046
Author(s):  
Alba Fernandez-Encinas ◽  
Agustín García-Peiró ◽  
Javier del Rey ◽  
Jordi Ribas-Maynou ◽  
Carlos Abad ◽  
...  

Seminal plasma proteomics studies could represent a new approach for the determination of molecular elements driving male infertility, resulting in a better male infertility characterization. The aim of this study is to investigate proteomic differences in seminal plasma samples from fertile and infertile individuals. For that, semen samples were selected according to semen analysis, clinical pathology, and values of sperm DNA fragmentation (alkaline and neutral Comet assay and Sperm Chromatin Dispersion test). A total of 24 seminal plasma samples classified in four groups were processed: fertile donors (FD), recurrent miscarriage patients (RM), asthenoteratozoospermic patients (ATZ), and asthenoteratozoospermic patients with varicocele (ATZ-VAR). Results obtained by 2D-differential gel electrophoresis (2D-DIGE) revealed 26 spots significantly increased in fertile donors when compared to patient groups. Also, eight spots in the ATZ group and two in the ATZ-VAR group were decreased compared to the other groups. Twenty-eight proteins were identified by mass spectrometry (MS), most of them involved in metabolic and cellular processes and with a catalytic or binding function. Protein–protein interactions through Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) tool suggest that a large part of them were associated with each other. Furthermore, most of them were associated with ubiquitin C, indicating that it could play an important regulation role, resulting in a potential male infertility biomarker.



Aquaculture ◽  
2018 ◽  
Vol 491 ◽  
pp. 281-288 ◽  
Author(s):  
Tianyi Feng ◽  
Jamie Gosálvez ◽  
Carmen Lopez-Fernandez ◽  
Francisca Arroyo ◽  
Brian Paterson ◽  
...  


2009 ◽  
Vol 44 (5) ◽  
pp. 823-828 ◽  
Author(s):  
EI Cortés-Gutiérrez ◽  
F Crespo ◽  
C Serres-Dalmau ◽  
AL Gutiérrez de las Rozas ◽  
MI Dávila-Rodríguez ◽  
...  


2013 ◽  
Vol 25 (1) ◽  
pp. 233
Author(s):  
M. J. Sanchez-Calabuig ◽  
J. de la Fuente ◽  
P. Beltrán-Breña ◽  
E. Martinez-Nevado ◽  
J. F. Perez-Gutierrez ◽  
...  

There has been significant development over the last 20 years to improve genetic management of the captive bottlenose dolphin (Tursiops truncatus) by means of genome resource banking and assisted reproduction. Although standard semen parameters have been analysed in some detail, very little is known about sperm DNA fragmentation (SDF) in this species. The aim of this study was to develop a sperm chromatin dispersion test (SCDt) for the bottlenose dolphin to establish the baseline level of SDF immediately after ejaculation and cryopreservation and to determine the dynamic loss of sperm DNA quality after ex vivo handing and incubation in conditions that mimic the female reproductive tract. Semen from 8 bottlenose dolphins was collected by manual stimulation. Initial validation of the SCDt was conducted by means of in situ nick translation and neutral comet assay using a proven fertile male. To investigate the dynamic loss of sperm chromatin (rate of sDF loss), thawed sperm samples were incubated at 37.9°C for up to 48 h, and aliquots of spermatozoa were assessed after 1, 4, 8, 24, and 48 h. Dolphin sperm nuclei with fragmented DNA exhibited large halos of dispersed DNA fragments, whereas those with nonfragmented DNA displayed small halos of nondispersed DNA. A high correlation (r2 = 0.82; P ≤ 0.01) was found between the respective assessments of the SCDt and the neutral comet assay. All nucleoids resulting in a large halo of dispersed chromatin were intensely positive to in situ nick translation. The level of sDF fragmentation observed immediately after ejaculation in fresh and frozen samples was relatively low (1–5%). After comparing different ejaculates of the same individual, differences were found. Chromatin stability was high during the first 48 h of ejaculation or post-thawing and incubation. Evaluation of the sDF dynamics of fresh and frozen–thawed spermatozoa revealed no significant increase in the baseline level of sDF or in the relative increase of DNA damage after 48 h of incubation. Our data suggest that cryopreservation does not induce a dramatic increase in sperm chromatin damage. Interestingly, sperm samples derived from aged animals resulted in an increased rate of DNA loss, which was observed after 60 min post-incubation.



2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
L S Chang ◽  
H C Lee ◽  
C T Hsu ◽  
H M Tsao ◽  
C C Huang ◽  
...  

Abstract Study question The performance and efficiency of the LensHooke® R10 test kit were evaluated by the clinical examination for precision, accuracy, and time. Summary answer The LensHooke® R10 based on sperm chromatin dispersion test offers not only quick testing for sperm DNA fragmentation but also reliable and accurate test results. What is known already Sperm chromatin dispersion (SCD) test, one of the most commonly used testing for sperm DNA fragmentation (SDF), can be conducted promptly and without the need for expensive laboratory instruments. However, the main disadvantage of the SCD test is inter-observer variability in categorizing the size of characteristics halos surrounding the core of sperm. Moreover, it takes more than one hour to accomplish whole assay procedures making this testing an inefficient diagnostic tool. These may hinder its broad availability among andrology laboratories or prevent it from being routinely used for the evaluation of male infertility. Study design, size, duration A total of 108 participants was included in this prospective study. Data was collected from the reproductive medicine center between June and December 2020. Participants/materials, setting, methods This study included 108 consecutive male partners of couples attending for assisted reproductive treatment. SDF was simultaneously tested by using LensHooke® R10 (R10) and Halosperm® G2 (G2) respectively. We evaluated the correlation and agreement between two SCD-based test kits. The repeatability and reproducibility of the SCD kits were assessed by intra-and inter-observer agreement experiments. The sensitivity, specificity, positive predictive value, negative predictive value for the R10 was determined by receiver operator characteristics (ROC) curve analysis. Main results and the role of chance The R10 produced more clear sperm core and dispersed chromatin, therefore highly recognizable images can be easily and accurately categorized when scoring of SDF. It took 50% less time for SDF testing by the R10 compared to the G2 (38.26 ± 9.85 minutes vs. 76.52 ± 19.7 minutes, P < 0.0001). The SDF% results showed a strong correlation for the R10 and G2 with Spearman’s coefficients of rank correlation (rho) above 0.8 (P < 0.0001, N = 108). The R10 showed 89.8% accuracy with 87.9% sensitivity, 90.8% specificity, 82.9% PPV, and 93.7% NPV on the measurement of SDF% at the threshold value of 22%. Intraclass correlation coefficients (ICC) >0.9 showed a strong agreement between two observers on the testing of SDF using the R10. ICC >0.9 showed a high intra-observer agreement within 4 repeated testing on SDF using the R10. The R10 showed an intra-observer’s precision of coefficient variation, CV < 10% for SDF%. In addition, SDF% test results obtained by the R10 for asthenospermic (31.8% ± 16.7%), teratospermic (22.9% ± 14.4%), and oligoasthenoteratozoospermic samples (36.6% ± 14.4%) were significantly higher than that observed in normozoospermic samples (15.3% ± 10.2%, p < 0.05), was comparable with the G2. Limitations, reasons for caution The sample size of 4 semen specimens used to evaluate the intra-and inter-observer agreement was a limitation. Besides, evaluating the relationship between the SDF and clinical outcome of ART is necessary for further study. Wider implications of the findings: The new in vitro diagnostics reagent, LensHooke® R10, is a simple and quick test kit that offers reliable and accurate test results of sperm DNA fragmentation, can be routinely used in male infertility evaluation. Trial registration number CS2–20012



2018 ◽  
Vol 17 (1) ◽  
Author(s):  
Azha Syahril Azizan ◽  
Kamarul Bahyah Mustafa ◽  
Azantee Yazmie Abdul Wahab ◽  
Roszaman Ramli ◽  
Nurkhairulnisa Abu Ishak

Introduction: Traditionally, seminal fluid analysis is done to assess male infertility particularly sperm concentration, morphology and motility. Sperm chromatin dispersion test explores the quality of the sperm DNA structures. High sperm DNA fragmentation is associated with unexplained infertility, failure of assisted reproduction and recurrent miscarriages. Smoking has been associated with high sperm DNA fragmentation in some studies but not in others. Materials and Methods: A comparative cross-sectional study, involving 32 smokers and 32 non-smokers to determine the association between cigarette smoking and sperm DNA fragmentation. Semen samples were collected from patients undergoing seminal fluid analysis (SFA) at the IIUM Fertility Centre and IIUM Medical Centre O&G Clinic from January 2017 to June 2018. Sperm chromatin dispersion test was done and level of 15% is considered upper limit of normal. Results: 53.1% in the smoker group have abnormal level of sperm DNA fragmentation compared to 34.4% of nonsmokers. The median and interquartile range for smokers were 15.30 and 19.0 (10.425 - 29.375) respectively while for non-smokers were 8.25 and 17.8 (4.075 - 21.850) which was statistically significant (p= 0.012). It was also noted that three participants in the smoker group (9.4%) has very high sperm DNA fragmentation index of more than 80% even though they have normal seminal fluid analysis. Conclusion: There is an association between smoking and high sperm DNA fragmentation. There is a trend of increased in DNA fragmentation in smokers even though their SFA results were normal.



Andrology ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 610-617 ◽  
Author(s):  
Haitham Elbardisi ◽  
Renata Finelli ◽  
Ashok Agarwal ◽  
Ahmad Majzoub ◽  
Ralf Henkel ◽  
...  


2020 ◽  
Vol 32 (10) ◽  
pp. 948 ◽  
Author(s):  
Stephen D. Johnston ◽  
Carmen López-Fernández ◽  
Eloise Pappin ◽  
Alexandra Hampe ◽  
Robert Doneley ◽  
...  

Herein we report a simple method for assessing avian sperm DNA fragmentation (SDF) using the sperm chromatin dispersion test (SCDt). The presence of sperm DNA damage was confirmed indirectly by correlating results of the SCDt determined in three bird species with results of a corresponding neutral comet assay (r=0.99; P<0.005). Frozen–thawed spermatozoa of each species were also incubated at 37°C for 5h and the within- and between-species variation of SDF, as an indicator of sperm DNA longevity, examined. The dynamic assessment of SDF using the SCDt revealed species and individual bird (rooster and turkey) differences in sperm DNA longevity.



2017 ◽  
Vol 89 (3) ◽  
pp. 212 ◽  
Author(s):  
Luciano Negri ◽  
Renzo Benaglia ◽  
Emanuela Monti ◽  
Emanuela Morenghi ◽  
Alessandro Pizzocaro ◽  
...  

Background: antioxidants supplementation improves sperm quality, but few trials have analyzed the effects on sperm DNA fragmentation (SDF). This study compares the effectiveness of SOD-based antioxidant supplementation plus hydroxytyrosol and carnosol in reducing SDF with other antioxidants without SOD, hydroxytyrosol, and carnosol. Materials and methods: men with high SDF at baseline were selected in our clinical database. The patients taken into account had a 2-month control. SDF was measured by Sperm Chromatin Dispersion test (SCD). Untreated men were used as a control group. The remaining subjects received some oral antioxidant supplements (12 different combinations of both hydrophilic and lipophilic antioxidants), with some of them receiving nutritional support with a SOD-based antioxidant supplementation plus hydroxytyrosol and carnosol. Results: 118 men were selected for a retrospective study. Mean age 39.3 ± 5.4 years. Fifteen had no treatment, 55 were treated with a SOD-based antioxidant supplementation plus hydroxytyrosol and carnosol, and 48 took some antioxidant supplements for 2 months. Clinically, variations of at least 10% in baseline values of classic semen parameters and sperm DNA fragmentation were taken into consideration. Classic seminal parameters did not vary significantly in the three groups, with the exception of viability (p = 0.001). We assessed which of the active substances (no. 19) in different formulations were associated with variations in SDF. In the multivariable analysis of the 7 active substances that passed the univariable analysis, only the SOD molecule appeared to be linked to an improvement in SDF (< 0.0001). In detail, only one patient in the control group showed a spontaneous improvement in SDF (6%), compared to 16/48 (33%) of those taking various oral antioxidant supplements, and 31/55 (56%) of those taking a SOD-based antioxidant supplementation plus hydroxytyrosol and carnosol. Conclusions: SOD-based antioxidant supplementation plus hydroxytyrosol and carnosol seems to provide a better chance of improving sperm DNA integrity than other classical antioxidant molecules.



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