Current Issue : July - September Volume : 2015 Issue Number : 3 Articles : 6 Articles
Currentmethods of analyzing spermchromatin competency overlook the inner spermcompartmentwhich is inaccessible to probes\nand reagents. By breaking the molecular protamine disulfide bridges, theDNAtoroids are exposed to integrity analysis.Theaimwas\nto develop a simple nuclear toroid test and determine its association with fertilization, pregnancy, and miscarriage. The approach\ninvolved treating washed sperm remaining after ICSI procedures (N = 35 cases) with acidified Triton X-100 and dithiothreitol\n(DTT) before Diff-Quik staining. Percentages of sperm with normal chromatin indicated by light-colored nuclei were assessed.\nThe toroid integrity test showed more sperm with normal chromatin in the pregnant group (73.6 �± 1.7%, mean �± SEM) when\ncompared with themiscarriage (51.2 �± 6.6%) or nonpregnant groups (60.9 �± 4.8%). Furthermore, the toroid results were correlated\nwith ICSI fertilization (R = 0.32, P = 0.04) and pregnancy outcome (pregnant cases 73.6 �± 1.7% versus nonpregnant 58.0 �± 3.9%,\nP = 0.001). ROCcalculated cut-offwas >70.0% for normal toroid integrity (sensitivity 0.98, specificity 0.33, and diagnostic accuracy\n78.3%). An association between normal sperm toroid integrity and miscarriage was evident when the staining procedure included\nacidified detergent DTT pretreatment....
Background. Semen analysis is the cornerstone in the evaluation of male (in)fertility. However, there are men with normal semen\ntests but with impaired fertilizing ability, as well as fertile men with poor sperm characteristics. Thus, there is rising interest to\nfind novel parameters that will help to predict and define the functional capacity of spermatozoa. Methods.We examined whether\nthere is a correlation between semen parameters (count, progressive motility, and morphology) and protein expression/activity\nof antioxidative defense enzymes in seminal plasma from 10 normospermic subjects. Results. Sperm progressive motility was\nin positive correlation with seminal plasma protein expression of both superoxide dismutase (SOD) isoforms (MnSOD and\nCuZnSOD) and catalase. Also, positive correlation was observed between sperm count and MnSOD protein expression, as well\nas between spermmorphology and protein expression of catalase in seminal plasma. In contrast, protein expression of glutathione\nperoxidase was not in correlation with any sperm parameter, while its activity negatively correlated with sperm morphology and\nmotility. Conclusions.These data suggest that evaluation of protein expression of antioxidative defense enzymes in seminal plasma\nmight be of importance in the evaluation of male fertility status and that could be used as an additional biomarker along with classic\nsemen analysis in assessment of semen quality....
Oxidative stress (OS) plays an essential role in male infertility aetiology by affecting sperm quality, function, and also the integrity of\nspermDNA.The assessment of oxidative stress in semen may be an important tool to improve the evaluation of spermreproductive\ncapacity. The purpose of this study was the evaluation of any possible relation between the unbalance of oxidative stress caused\nby superoxide anion in the ejaculate with the presence of sperm DNA fragmentation and high concentration of round cells. 56\nsemen samples frommales fromcouples suffering frominfertility were evaluated according toWorld Health Organisation (WHO)\n2010 guidelines. Oxidative stress levels from N1 (low) to N4 (high) were assessed in ejaculates using oxiSperm; DFI (sperm DNA\nfragmentation index) as assessed by the SCSA (Sperm Chromatin Structure Assay) was used for evaluation of sperm chromatin\nintegrity. Our data show that high oxidative stress (N3-N4 levels) correlated positively with a DFI ? 30% (???? = 0.0379) and round\ncells ?1.500.000/mL (???? = 0.0084). In conclusion, OS increases sperm DNA damage.Thus evaluation of semen OS extent of sperm\nDNA damage in infertile man could be useful to develop new therapeutic strategies and improve success of assisted reproduction\ntechniques (ART)....
Background. The natural cycle is the prototype to which we aspire to emulate in assisted reproduction techniques. Increasing\nevidence is emerging that controlled ovarian hyperstimulation (COH) with exogenous gonadotropins may be detrimental to\noogenesis, embryo quality, and endometrial receptivity.This research aimed at assessing the impact of COH on the intrafollicular\nmilieu by comparing follicular fluid (FF) cytokine profiles during stimulated in vitro fertilization (IVF) and modified natural\ncycle (MNC) IVF. Methods. Ten women undergoing COH IVF and 10 matched women undergoing MNC IVF were recruited\nfor this pilot study. 40 FF cytokine concentrations from individual follicles and plasma were measured by fluid-phase multiplex\nimmunoassay. Demographic/cycle/cytokine data were compared and correlations between cytokines were computed. Results. No\nsignificant differences were found between COHandMNC groups for patient and cycle demographics, including outcome. Overall\nmean FF cytokine levels were higher in the MNC group for 29/40 cytokines, significantly so for leukaemia inhibitory factor\nand stromal cell-derived factor-1????. Furthermore, FF MNC cytokine correlations were significantly stronger than for COH data.\nConclusions.These findings suggest that COH perturbs intrafollicular cytokine networks, in terms of both cytokine levels and their\ninterrelationships. This may impact oocyte maturation/fertilization and embryo developmental competence....
We investigated sperm nuclear vacuolation in relation to acrosome reactions and the maintenance of sperm motility. Thirty male\npatients who visited our Male Infertility Clinic were enrolled.These patients underwent conventional semen analyses, Acrobeads\ntests, and high-magnification observation of the sperm head to evaluate the degree of nuclear vacuolation on the Acrobeads test\nscoring after 24 hours of incubation. The presence of acrosome reactions was evaluated using the Acrobeads test. The spermatozoa\nwere classified into three groups: (I) those bound to MH61-beads, (II) motile spermatozoa that did not bind to MH61-beads,\nand (III) immotile spermatozoa that did not bind to MH61-beads. The percentage of spermatozoa with large nuclear vacuoles\n(%LNV) was compared between the three groups. The degree of sperm nuclear vacuolation was evaluated in 17,992 ejaculated\nspermatozoa. The mean %LNVs were 2.4% in group I, 5.8% in group II, and 9.8% in group III. These values were significantly\ndifferent from each other (P < 0.001, paired t-test). There were no correlations between the %LNV values and the Acrobeads\nscores. In conclusion, the degree of sperm nuclear vacuolation was significantly lower in the acrosome-reacted spermatozoa and\nspermatozoa with maintained motility, and higher in the immotile spermatozoa that did not bind to MH61-beads....
Protein ubiquitin-proteasome (ubiquitin-proteasome) system is the major mechanism responsible for protein degradation in\neukaryotic cell. During spermatogenesis, the replacement of histone by protamine is vital for normal sperm formation, which\nis involved in ubiquitination enzymes expressed in testis. Recently, histone ubiquitin ligases have been shown to play critical\nroles in several aspects of spermatogenesis, such as meiotic sex chromosome inactivation (MSCI), DNA damage response, and\nspermiogenesis. In this review, we highlight recent progress in the discovery of several histone ubiquitin ligases and elaborate\nmechanisms of how these enzymes are involved in these processes through knockout mouse model. Using Huwe1, UBR2, and\nRNF8 as examples, we emphasized the diverse functions for each enzyme and the broad involvement of these enzymes in every\nstage, from spermatogonia differentiation and meiotic division to spermiogenesis; thus histone ubiquitin ligases represent a class\nof enzymes, which play important roles in spermatogenesis through targeting histone for ubiquitination and therefore are involved\nin transcription regulation, epigenetic modification, and other processes essential for normal gametes formation...
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