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BACKGROUND: The assessment of sperm DNA integrity has been proposed as a complementary test to conventional mammalian semen analysis. In this sense, single-strand (SSB) and double-strand (DSB) DNA breaks, the two types of sperm DNA fragmentation (SDF), have been reported to have different aetiologies and to be associated to different fertility outcomes in bovine and humans. Considering that no studies in porcine have addressed how SDF may affect sperm quality and fertility outcomes, the present work aimed to determine the impact of global DNA damage, SSB and DSB on sperm quality and in vitro fertilising ability. To this end, 24 ejaculates (one per boar) were split into three aliquots: the first was used to assess sperm quality parameters through a computer-assisted sperm analysis (CASA) system and flow cytometry; the second was used to perform in vitro fertilisation, and the third, to evaluate sperm DNA integrity using alkaline and neutral Comet assays. RESULTS: The results showed that global DNA damage negatively correlates (P 0.05). CONCLUSION: Considering all these findings, this work sets a useful model to study how SDF negatively influences fertility.
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Animals , Male , Cattle , Spermatozoa , DNA Damage , Swine , Embryonic Development , DNA Fragmentation , Fertilization , MammalsABSTRACT
Background & objectives: Recurrent pregnancy loss (RPL) is one of the devastating complications of pregnancy and current focus lies in addressing the management of paternal factors. Dysregulation in selective transcripts delivered to oocyte at fertilization can result in pregnancy losses and adversely affect embryogenesis. The objective of this study was to assess the effect of yoga-based lifestyle intervention (YBLI) on seminal oxidative stress (OS), DNA damage and spermatozoal transcript levels. Methods: The present study was a part of a prospective ongoing exploratory study and 30 male partners of couples with RPL were included from August 2016 to June 2017. Semen samples were obtained at baseline and at the end of YBLI (21 days). Gene expression analysis was performed by quantitative polymerase chain reaction on spermatozoal FOXG1, SOX3, OGG1, PARP1, RPS6, RBM9, RPS17 and RPL29. The levels of seminal OS and sperm DNA damage was assessed by measuring levels of reactive oxygen species (ROS) by chemiluminescence and DNA fragmentation index (DFI) by sperm chromatin structure assay. Results: SOX3, OGG1 and PARP1 were observed to be upregulated, while FOXG1, RPS6, RBM9, RPS17 and RPL29 showed downregulation. A significant reduction in ROS levels, an increase in sperm motility, sperm count (done twice) and a decrease in DFI was seen after YBLI. Interpretation & conclusions: Adopting YBLI may help in a significant decline in oxidative DNA damage and normalization of sperm transcript levels. This may not only improve pregnancy outcomes but also improve the health trajectory of the offspring.
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Objective The molecular mechanisms underlying sperm DNA damage remain uncertain. This study aimed to determine the expression difference of Prdx2 protein between normal and damaged sperm DNA,and analyze the correlation between expression of Prdx2 protein in human mature spermatozoa and sperm DNA damage．Methods Semen specimens of sixty-seven male infertility patients were collected．They were separated in three groups according to the sperm DNA damage levels: normal group， slight damage group，and severe damage group．Total protein of human of mature spermatozoa was extracted．The expression of Prdx2 protein was detected by western blotting．The Localization of Prdx2 in spermatozoa was detected by immunofluorescence.Results Comparing the expression of Prdx2 protein with group normal(9.06±1.80), group slight damage(6.32±1.89） and group severe damage（2.87±0.83） decreased by 30.2% and 68.2% respectively (P<0.01).Immunofluorescence showed that Prdx2 was mainly distributed in the mitochondria and nuclear of spermatozoa.Immunofluorescence Results showed that Prdx2 was mainly located in the mitochondria of human sperm midsection and the nucleus region of the sperm head. The expression of Prdx2 in both group slight damage and group severe damage was lower than that in the group normal.The positive Prdx2 response was significantly reduced in group severe damage.The protein expression of Prdx2 was negatively correlated with DFI(r=-0.478,P<0.01), and was positively correlated with progressive motility and total motility(r=0.135、0.128，P<0.01).Conclusion Human sperm Prdx2 protein expression may be involved in protecting sperm DNA and affecting sperm motility by maintaining intracellular redox balance.
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Resumen OBJETIVO: Determinar las repercusiones del daño al ADN espermático en los parámetros seminales más estudiados en diagnóstico clínico de varones infértiles. MATERIALES Y MÉTODOS: Estudio de casos y controles, prospectivo y comparativo efectuado en pacientes masculinos atendidos en el Centro Integral de la Mujer y Reproducción Asistida de Puebla, México. Parámetros de estudio: edad, movilidad, morfología, diagnóstico seminal, leucocitos y factor de infertilidad. Los resultados se analizaron con Graphpad Prisma 5.0 y se consideraron estadísticamente significativos con p < 0.005. RESULTADOS: Se estudiaron 110 pacientes: 33 con mala integridad del ADN espermático (grupo 1) y 77 con buena integridad (grupo 2). La concentración espermática y la movilidad tipo A+B en el grupo 2 fue significativamente más alta que en el grupo 1 (p < 0.0001) en donde se registró mayor número de móviles no progresivos e inmóviles. La morfología normal fue más alta en el grupo 2 (p = 0.0063). En los varones menores de 40 años se observó un número significativamente mayor de casos de buena integridad espermática (p = 0.013). El diagnóstico seminal demostró que los varones con mala integridad tuvieron alteraciones espermáticas más severas. Los factores de infertilidad más frecuentes implicados en ambos grupos fueron: aborto de repetición, edad de la pareja, falla previa en la técnica de reproducción asistida, factor masculino severo y factor tubárico. CONCLUSIONES: La mala integridad del ADN espermático tiene repercusiones en la concentración espermática, movilidad y morfología, además de alterar el diagnóstico seminal, pues los varones tuvieron trastornos más severos cuando no hubo algún factor de infertilidad que describiera un comportamiento específico relacionado con la mala integridad espermática.
Abstract OBJECTIVE: To determine the impact of sperm DNA damage on the most studied seminal parameters in clinical diagnosis of infertile males. MATERIALS AND METHODS: Prospective and comparative case-control study that included male patients seen at Centro Integral de la Mujer y Reproducción Asistida de Puebla, Mexico. Study parameters: age, mobility, morphology, seminal diagnosis, leukocytes and infertility factor. The results were analyzed with Graphpad Prism 5.0 and were considered statistically significant with p < 0.005. RESULTS: 110 male patients were studied: 33 patients with poor sperm DNA integrity (group 1) and 77 patients with good integrity (group 2). Sperm concentration and type A + B mobility in group 2 was significantly higher than in group 1 (p <0.0001), where a greater number of non-progressive and immobile mobiles was recorded. The normal morphology was higher in group 2 (p = 0.0063). In men under 40 years of age, a significantly higher number of cases of good sperm integrity was observed (p = 0.013). The seminal diagnosis showed that males with poor integrity had more severe sperm alterations. The most frequent infertility factors involved in both groups were: repeat abortion, age of the couple, previous failure in the technique of assisted reproduction, severe male factor and tubal factor. CONCLUSIONS: The poor integrity of the sperm DNA has repercussions on sperm concentration, mobility and morphology, alters the seminal diagnosis, since males had more severe alterations when there was no infertility factor that described a specific behavior related to poor sperm integrity.
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Objective To investigate the application value of sperm nucleoprotein immaturity and sperm DNA damage detection in in vitro fertilization(IVF).Methods From Mar.2015 to Feb.2016,routine sperm analysis,sperm nucleoprotein immaturity and sperm DNA damage detection were performed in 102 patients with infertility,and the correlation between these parameters were analyzed.Results Sperm DNA fragmentation rate was negatively correlated with IVF optimal embryos rate and sperm viability(P0.05).Sperm nucleoprotein immaturity rate was not correlated with IVF optimal embryos rate and fertility rate(P>0.05),while was negatively correlated with sperm concentration(P<0.05).Conclusion Sperm DNA fragmentation rate could be closely correlated with IVF optimal embryos rate,which might be with prediction value in IVF treatment.
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Sperm DNA damage is prevalent among infertile men and is known to influence natural reproduction. However, the impact of sperm DNA damage on assisted reproduction outcomes remains controversial. Here, we conducted a meta-analysis of studies on sperm DNA damage (assessed by SCSA, TUNEL, SCD, or Comet assay) and clinical pregnancy after IVF and/or ICSI treatment from MEDLINE, EMBASE, and PUBMED database searches for this analysis. We identified 41 articles (with a total of 56 studies) including 16 IVF studies, 24 ICSI studies, and 16 mixed (IVF + ICSI) studies. These studies measured DNA damage (by one of four assays: 23 SCSA, 18 TUNEL, 8 SCD, and 7 Comet) and included a total of 8068 treatment cycles (3734 IVF, 2282 ICSI, and 2052 mixed IVF + ICSI). The combined OR of 1.68 (95% CI: 1.49-1.89; P < 0.0001) indicates that sperm DNA damage affects clinical pregnancy following IVF and/or ICSI treatment. In addition, the combined OR estimates of IVF (16 estimates, OR = 1.65; 95% CI: 1.34-2.04; P < 0.0001), ICSI (24 estimates, OR = 1.31; 95% CI: 1.08-1.59; P = 0.0068), and mixed IVF + ICSI studies (16 estimates, OR = 2.37; 95% CI: 1.89-2.97; P < 0.0001) were also statistically significant. There is sufficient evidence in the existing literature suggesting that sperm DNA damage has a negative effect on clinical pregnancy following IVF and/or ICSI treatment.
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This study compared three cryopreservation protocols on sperm functions, IVF outcomes, and embryo development. Epididymal spermatozoa cryopreserved using slow-cooling (18% w/v raffinose, RS-C) were compared with spermatozoa vitrified using 0.25 M sucrose (SV) or 18% w/v raffinose (RV). The motility, vitality, and DNA damage (TUNEL assay) of fresh control (FC) spermatozoa were compared with post-thawed or warmed RS-C, RV, and SV samples. Mouse oocytes (n = 267) were randomly assigned into three groups for insemination: RV (n = 102), RS-C (n = 86), and FC (n = 79). The number and the proportion of two-cell embryos and blastocysts from each treatment were assessed. Sperm motility (P < 0.01) and vitality (P < 0.05) were significantly reduced after vitrification compared with slow-cooled spermatozoa. However, DNA fragmentation was significantly reduced in spermatozoa vitrified using sucrose (15 ± 1.8% [SV] vs 26 ± 2.8% [RV] and 27 ± 1.2% [RS-C]; P < 0.01). Although the number of two-cell embryos produced by RS-C, RV, and FC spermatozoa was not significantly different, the number of blastocysts produced from two-cell embryos using RV spermatozoa was significantly higher than FC spermatozoa (P = 0.0053). This simple, small volume vitrification protocol and standard insemination method allows successful embryo production from small numbers of epididymal spermatozoa and may be applied clinically to circumvent the need for ICSI, which has the disadvantage of bypassing sperm selection.
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Varicocele has been associated with reduced male reproductive potential. With the advances in biomolecular techniques, it has been possible to better understand the mechanisms involved in testicular damage provoked by varicocele. Current evidence suggests the central role of reactive oxygen species (ROS) and the resultant oxidative stress (OS) in the pathogenesis of varicocele-associated male subfertility although the mechanisms have not yet been fully described and it is likely to be multifactorial. Excessive ROS is associated with sperm DNA fragmentation, which may mediate the clinical manifestation of poor sperm function and fertilization outcome related to varicocele. Testing of ROS/OS and DNA fragmentation has the potential to provide additional diagnostic and prognostic information compared to conventional semen analysis and may guide therapeutic management strategies in individual patient.
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<p><b>OBJECTIVE</b>To investigate the effect of simulated microgravity and carbon ion irradiation (CIR) on spermatogenic cell apoptosis and sperm DNA damage to the testis of male Swiss Webster mice, and assess the risk associated with space environment.</p><p><b>METHODS</b>Sperm DNA damage indicated by DNA fragmentation index (DFI) and high DNA stainability (HDS) was measured by sperm chromatin structure assay (SCSA). Apoptosis of spermatogenic cells was detected by annexin V-propidium iodide assay. Bax (the expression levels of p53) and proliferating cell nuclear antigen (PCNA) were measured by immunoblotting; p53 and PCNA were located by immunohistology.</p><p><b>RESULTS</b>HDS, DFI, apoptosis index, and the expression levels of p53 and Bax were detected to be significantly higher in the experimental groups (P<0.05) compared with those in the control group; however, the PCNA expression varied to a certain degree. p53- and PCNA- positive expression were detected in each group, mainly in relation to the spermatogonic cells and spermatocytes.</p><p><b>CONCLUSION</b>The findings of the present study demonstrated that simulated microgravity and CIR can induce spermatogenic cell apoptosis and sperm DNA damage. Sperm DNA damage may be one of the underlying mechanisms behind male fertility decline under space environment. These findings may provide a scientific basis for protecting astronauts and space traveler's health and safety.</p>