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We aimed to study the association between sperm DNA fragmentation and recurrent pregnancy loss (RPL) in the Chinese population via a retrospective observational study of Chinese couples who had experienced RPL between May 2013 and August 2018. The study population included 461 men from couples with RPL and 411 men from a control group (couples with clinical pregnancy via in vitro fertilization owing to female causes). Routine semen analysis, sperm chromatin analysis, and microscopic (high-power) morphological analysis were performed using semen samples. Semen samples were assessed for volume, sperm count, and motility. The sperm DNA fragmentation index (DFI) was calculated, and the median DFI was obtained. Men were categorized as having normal (37.8%; DFI ≤ 15.0%), moderate (33.6%; 15.0% < DFI < 30.0%), or severe (28.6%; DFI ≥ 30.0%) DNA fragmentation levels. The percentage of men with severe DNA fragmentation was significantly higher in the RPL (42.3%) group than that in the control group (13.1%), whereas the percentage of men with normal levels of DNA fragmentation was significantly lower in the RPL group (22.8%) than that in the control group (54.7%). Subsequent analysis also demonstrated that the sperm DNA fragmentation rate had a moderate reverse correlation with the sperm progressive motility rate (r = -0.47, P < 0.001) and the total motile sperm count (r = -0.31, P < 0.001). We found a positive correlation between RPL and sperm DNA fragmentation. The results suggest that increased sperm DNA damage is associated with RPL.
ABSTRACT
An increased amount of DNA fragmentation in the spermatozoa (SDF) is linked to male infertility. The Sperm Chromatin Structure Assay (SCSA) is widely used for analysis of SDF. However, the current software (SCSASoft®) linked to this assay is licensed and often located within larger diagnostic centers. In this study, we present a protocol for using other types of software than SCSASoft® to determine the SDF index (DFI) with clinical relevance. This protocol is engineered after collecting and analyzing 254 samples from fertility patients and sperm donors over a 15-month period. DFI is analyzed using a strict protocol where the spermatozoa are treated with a strong acid (pH 1.2) followed by acridine orange. DFI is determined by a standard flow cytometric software, FACSDiva 6.1.3. Analysis of the outcome of the fertility treatment is included for 137 patients receiving either intrauterine inseminations (IUI) or timed coitus (TC). The results show that the chance of pregnancy declines as DFI increases. We also found that the male DFI affects the chance of pregnancy independent of the female age. We have shown that a standard flow cytometric software can be used when determining a clinical relevant DFI. These findings are a significant step toward implementing the analysis as a part of the routine, in-house diagnosing of the male fertility patient and subsequently optimizing the treatment course of the couple with reduced human and financial costs.
ABSTRACT
Sperm DNA fragmentation (SDF) has been linked with male infertility, and previous studies suggest that SDF can have negative influence on pregnancy outcomes with assisted reproduction. We performed a retrospective review of consecutive couples with a high SDF level that had intracytoplasmic sperm injection (ICSI) using testicular sperm (T-ICSI). We compared the T-ICSI outcomes to that of two control groups: 87 couples with failed first ICSI cycle and who had a second ICSI cycle using ejaculated sperm (Ej-ICSI), and 48 consecutive couples with high sperm chromatin structure assay (SCSA)-defined SDF (>15%) that underwent an ICSI cycle using ejaculated sperm after one or more failed ICSI cycles (Ej-ICSI-high SDF). The mean number of oocytes that were retrieved and the total number of embryos were not different among the three groups. The mean number of transferred embryos in the T-ICSI group was higher than the Ej-ICSI group but not significantly different than the Ej-ICSI-high SDF group (1.4, 1.2, and 1.3, respectively, P 0.05). No significant difference was found in live birth rate when comparing T-ICSI to Ej-ICSI and Ej-ICSI-high SDF groups. The results suggest that pregnancy outcomes and live birth rates with T-ICSI are not significantly superior to Ej-ICSI in patients with an elevated SCSA-defined sperm DNA fragmentation and prior ICSI failure(s).
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It is becoming increasingly clear that eukaryotic genomes are subjected to higher-order chromatin organization by the CCCTC-binding factor/cohesin complex. Their dynamic interactions in three dimensions within the nucleus regulate gene transcription by changing the chromatin architecture. Such spatial genomic organization is functionally important for the spatial disposition of chromosomes to control cell fate during development and differentiation. Thus, the dysregulation of proper long-range chromatin interactions may influence the development of tumorigenesis and cancer progression.
Subject(s)
Humans , Carcinogenesis , Chromatin , Gene Expression Regulation , GenomeABSTRACT
Objective@#Sperm DNA fragmentation (SDF) is widely used to predict male infertility and the methods of detecting SDF are varied. This study aimed to compare two methods of SDF detection and investigate the correlation between SDF and sperm quality.@*METHODS@#Using sperm chromatin structure assay (SCSA) and sperm chromatin dispersion test (SCD), we detected SDF in 108 semen samples collected in the Center of Reproduction and Genetics of Suzhou Municipal Hospital. We compared the results of the two methods and analyzed the correlations of SDF routine semen parameters, sperm morphology and the age of the patients.@*RESULTS@#A significant consistency was found in the SDF index (DFI) between the two methods (P<0.01). The DFI was correlated negatively with sperm motility, the percentage of progressively motile sperm, and that of morphologically normal sperm (P <0.01), but positively with the teratozoospermia index (P <0.01 in SCSA and P <0.05 in SCD). The DFI measured by SCSA showed a significantly positive correlation with the patients' age (P <0.01), but not that obtained by SCD.@*CONCLUSIONS@#The results of both SCSA and SCD play an important role in predicting sperm quality. As a clinical index, the DFI has a predictive value for male infertility. However, the results of different detecting methods vary widely, which calls for further studies on their standardization.
Subject(s)
Humans , Male , Chromatin , Genetics , Physiology , DNA Fragmentation , Infertility, Male , Diagnosis , Semen , Physiology , Semen Analysis , Sperm Motility , Spermatozoa , PhysiologyABSTRACT
Cumulative evidence demonstrated that the chromatin modification plays important roles in the processes of DNA replication,transcription,repair and recombination.Both of the generation of DNA lesions and the activation of DNA damage response (DDR) to ionizing radiation could be affected by the chromatin modifications.This paper reviewed the recent research progresses in the chromatin structure modifications and its role in DDR,especially the influence of characteristic chromatin structure and histone modification on the radiation sensitivity of tumor cells.
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OBJECTIVE: Several publications have established a relationship between sperm DNA damage and male factor infertility, based on data from America, Europe, and Asia. This study aimed to compare the extent of sperm DNA damage in sperm samples from Nigerian men with unexplained infertility and in sperm samples from a fertile group composed of sperm donors who had successfully impregnated a female partner naturally or through assisted conception. METHODS: A total of 404 men underwent male fertility evaluation at Androcare Laboratories and Cryobank participated in this study. Semen analysis and a sperm chromatin structure assay (SCSA) were performed on all subjects. RESULTS: The men in the unexplained infertility group were slightly older than the men in the fertile sperm group (36+/-10 years vs. 32+/-6 years, p=0.051). No significant difference was observed between the two groups in semen analysis parameters (p> or =0.05). Men in the unexplained infertility group with normal semen parameters had a significantly higher DNA fragmentation index (DFI) than men in the fertile sperm group (27.5%+/-7.0% vs. 14.1%+/-5.3%, p<0.05). In the unexplained infertility group, 63% of the men had a DFI greater than 20%, compared to 4% in the fertile sperm group. In the unexplained infertility group, 15.2% of the subjects had a DFI greater than 30%, compared to 1% in the fertile sperm group. CONCLUSION: Our study showed that the SCSA may be a more reliable predictor of fertility potential than traditional semen analysis in cases of unexplained infertility.
Subject(s)
Female , Humans , Male , Americas , Asia , Chromatin , DNA Damage , DNA Fragmentation , Europe , Fertility , Fertilization , Infertility , Semen , Semen Analysis , Spermatozoa , Tissue DonorsABSTRACT
Objective To assess sperm chromatin structure assay (SCSA) and sperm chromatin dispersion test (SCD) for DNA fragmentation evaluation in human infertility, and the correlation between these two methods. Methods We used SCSA and SCD assays to detect DNA fragmentation in sperm from 134 infertile men. The correlation of SCSA and SCD assays was analyzed. The sperm DNA fragmentation index (DFI) was divided into 3 groups (≤15%DFI, >15~≤30%DFI and>30%DFI), and the difference between SCSA and SCD assays was assessed. Results The SCSA assay was strongly correlated with the SCD assay for sperm DNA fragmentation (r=0.915, P15~ ≤30%DFI and>30%DFI groups. However, SCD showed higher levels of DNA fragmentation than that measured by SCSA for≤15%DFI group (13.50 4.82 vs 9.79 2.60, P<0.001). Conclusion There is a strong positive correlation between SCSA and SCD assays in detection of DNA fragmentation. SCD assay showed higher levels of DNA fragmentation than that measured by SCSA for≤15%DFI group.
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Major depression is a devastating disorder of which lifetime prevalence rate is as high as up to 25% in general population. Although the etiology of the disorder is still poorly understood, it is generally accepted that both genetic and environmental factors are involved in the precipitation of depression. Stressful lifetime events are potent precipitating environmental factors for major depression and early-life stress is in particular an important element that predisposes individuals to major depression later in life. How environmental factors such as stress can make our neural networks susceptible to depression and how those factors leave long-lasting influences have been among the major questions in the field of depression research. Epigenetic regulations can provide a bridging mechanism between environmental factors and genetic factors so that these two factors can additively determine individual predispositions to major depression. Here we introduce epigenetic regulations as candidate mechanisms that mediate the integration of environmental adversaries with genetic predispositions, which may lead to the development of major depression, and summarize basic molecular events that underlie epigenetic regulations as well as experimental evidences that support the active role of epigenetic regulation in major depression.
Subject(s)
Depression , DNA Methylation , Epigenomics , Genetic Predisposition to Disease , Prevalence , Social Control, FormalABSTRACT
Previous research using microdensitometric scanning and computer graphic image analysis showed that T-banded segments of human metaphase chromosomes usually exhibit an asymmetrical distribution of high density (HD) chromatin between sister chromatids. Here, we employed the same methods to analyze HD chromatin distribution at opposite ends of T-banded human lymphocyte chromosomes. This study revealed that in most chromosomes with an asymmetrical distribution of HD chromatin at both ends, the highest densities of each arm were located in opposite chromatids. The frequency of this configuration was 0.792 per chromosome, indicating that the highest chromatin densities of the terminal segments of T-banded human chromosomes were non-randomly distributed at opposite chromosome arms. The possible relationship of this observation to the mode of replication of the terminal chromosome region is briefly discussed.
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We used a rapid and simple protocol using lysolecithin for mapping HS sites in vivo. The protocol is based on partial digestion with DNase I of exponentially growing cells following permeabilization by short treatment with lysolecithin. Using this protocol, we analyzed the chromatin structure of the region surrounding two overlapping elements, an origin of bidirectional DNA replication and the GAS41 promoter, in chicken myelomonocytic HD11 cells arrested in G0, G0 and S phases as well as at the G0/S border. The results show that the chromatin of this region became more nuclease sensitive when cells were arrested in G0 phase and that this change in chromatin structure was reversible after the cells began to enter S phase.
Subject(s)
Humans , Cell Cycle/genetics , Chromatin/genetics , DNA Replication/genetics , Transcription Factors/genetics , Cell Line , Cell Cycle/physiology , Chromatin/chemistry , Chromatin/metabolismABSTRACT
Objective To study the factors effecting on flow cytometric sperm chromatin structure assay.Methods The SCSA explores the metachromatic properties of acridine orange (AO) and flow cytometry to monitor the susceptibility of sperm chromatin DNA to acid induced denaturation in situ because of the low pH treatment. Results COMP?t, ?t, SD?t value were different upon on the storage methods (①sperm was preserved in 4℃, ②sperm was cryopreservated after dilution ③sperm was cryopreservated). Results show that the second method above made the least artificial injury to sperm DNA. It did not affect the results if the samples were quickly thawed in a 37℃ water bath and detected immediately and the detect current velocity was lower than 300 cell/sec. The intra -CV was 7 28% and the internal CV was 8 92%. Mean and standard deviations of COMP?t were 8 7?11 0% in 511 healthy men. Because data present right skew distribution, the reference range of COMP?t is
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Among the various heat shock proteins (HSPs), members of the HSP70 and HSP90 families have drawn particular attention due to their heat shock-unrelated functions. HSP90, an ubiquitous and abundant member of the HSP90 family has been shown to be associated with a large array of protein factors. These proteins reside in the nucleus as well as in the cytoplasm and are involved in various physiological processes, such as, regulation of chromatin structure, cell cycle, cytoskelelal architecture, protein trafficking and protein synthesis. In this article, we focus our interest on the role of HSP90 in protein synthesis. Recent data obtained from a few laboratories strongly suggest that HSP90 interacts with the heme-regulated eukaryotic initiation factor 2α (elF-2α) kinase, also called the heme-regulated inhibitor, and causes its activation which leads to inhibition of protein synthesis. On the basis of data reported from various laboratories, including our own, we propose a possible model on the mechanism of HSP90- mediated activation of heme-regulated inhibitor and regulation of protein synthesis.