Aspects Of Sperm Function Research Articles

Addition of Vitamin C Mitigates the Loss of Antioxidant Capacity, Vitality and DNA Integrity in Cryopreserved Human Semen Samples.

Cryopreservation of human spermatozoa is a necessity for males suffering from infertility who cannot produce fresh semen for insemination. However, current ART cryopreservation protocols are associated with losses of sperm motility, vitality and DNA integrity, which are thought to be linked to the induction of oxidative damage and the toxic properties of commercial cryoprotectants (CPAs). Preventing or mitigating these losses would be hugely beneficial to sperm survival during ART. Therefore, in this in vitro investigation, lipid peroxidation, production of reactive oxygen species, movement characteristics, antioxidant capacity, vitality, and DNA integrity were examined in semen samples both pre- and post-cryopreservation with CPA supplementation. The findings revealed a 50% reduction in antioxidant capacity with CPA addition, which was accompanied by significant increases in generation of reactive oxygen species and formation of lipid aldehydes. These changes were, in turn, correlated with reductions in sperm viability, motility and DNA integrity. Antioxidant supplementation generated bell-shaped dose-response curves with both resveratrol and vitamin C, emphasising the vulnerability of these cells to both oxidative and reductive stress. At the optimal dose, vitamin C was able to significantly enhance vitality and reduce DNA damage recorded in cryopreserved human spermatozoa. An improvement in sperm motility did not reach statistical significance, possibly because additional pathophysiological mechanisms limit the potential effectiveness of antioxidants in rescuing this aspect of sperm function. The vulnerability of human spermatozoa to reductive stress and the complex nature of sperm cryoinjury will present major challenges in creating the next generation of cryoprotective media.

Development of a biomolecular approach to identify sperm functions and fertility using sperm RNAs.

Infertility affects a significant percentage of couples worldwide, and male factors contribute significantly to this problem. Traditional assessments of male fertility rely primarily on parameters such as sperm motility, morphology, viability, and concentration. However, these metrics often do not provide a comprehensive understanding of sperm function, which is critical not only for fertilization but also for successful embryo development. Herein, we used porcine spermatozoa as a model to investigate the potential of sperm RNA markers in assessing various aspects of sperm function from motility to fertility. Using artificial insemination, we evaluated male fertility based on the litter size of sows inseminated with sperm from 20 boars. In addition, we measured parameters such as weaning rate, death births, live births, and mummy births. Sperm functional parameters, including motility and kinematics, were assessed before and after in vitro capacitation. Finally, correlations between various sperm functional parameters and sperm RNA markers were explored. Our results revealed interesting relationships between sperm functional parameters. While motility and kinematics were correlated, they were not correlated with sperm capacitation status. Surprisingly, no significant correlations were found between these parameters and male fertility. However, specific parameters of sperm capacitation status after in vitro capacitation were correlated with weaning rate and live births, highlighting their importance in predicting successful fertilization. Further analysis of sperm RNA markers identified genes related to male fertility, including IZUMO1, known for its role in sperm-egg fusion. These genes showed correlations with motility, capacitation, and fertilization parameters, shedding light on their potential roles in sperm function. In conclusion, our study demonstrates that sperm RNA markers hold promise for the diagnosis and prognosis of various aspects of sperm function, providing valuable insights into male infertility. These markers may serve as diagnostic tools to improve our understanding of male fertility problems, ultimately benefiting couples struggling with infertility.

Sperm oxidative stress in the context of male infertility: current evidence, links with genetic and epigenetic factors and future clinical needs.

Male infertility is a relatively common condition responsible for around 30% of all infertility cases and contributing to another 20%. Although the traditional semen profile is used to diagnose this condition, the criteria at the heart of this analysis are purely descriptive and shed no light on the underlying etiology. Recent research on the causes of male infertility have revealed the importance of three major factors including genetic and epigenetic mutations and a state of oxidative stress. The fundamental complexity of spermatogenesis, involving the coordinated action of over 2000 genes, plus the fact that any gene defect causing infertility will be heavily selected against, means that the genetic landscape for male infertility is characterized by a large number of different mutations each one of which is extremely rare. Such mutations can only remain within the population as a result of passage through the female germ line or transmission via heterozygous males. However, the most common genetic cause of male infertility, Y-chromosome deletions, cannot be propagated by either of these mechanisms and arises de novo in every instance. The presence of Y chromosome mutation in around 5% of severely oligozoospermic males suggests that the male germ line is under a great deal of stress, one form of which is oxidative stress. The latter impairs all aspects of sperm function and also disrupts the integrity of DNA in the sperm nucleus. An oxidative attack on sperm DNA not only generates strand breaks but, more importantly, oxidative base adducts that are extremely mutagenic. It is proposed that the persistence of these lesions into S-phase of the first mitotic division generates de novo mutations that are potentially capable of impacting the long-term health and wellbeing of the offspring including the latter's fertility. To address this issue, the field desperately needs simple validated tests of oxidative stress in the male germ line, that can then be used to direct the appropriate management of these patients.

Analysis of the Functional Aspects of Sperm and Testicular Oxidative Stress in Individuals Undergoing Metabolic Surgery.

Metabolic surgery is a recommended treatment for obese patients that results in BMI reduction; however, the observed impact of this therapy on male fertility is inconsistent. This research aimed to study the effects of BMI changes after metabolic surgery on seminal analysis, sex hormonal profile, sperm functional integrity, and the seminal plasma lipid peroxidation levels. A prospective study was performed in 15 patients for whom metabolic surgery was recommended. The patients were evaluated by the techniques proposed in this study before and after the surgical procedure for 12 months. In each analysis, the male sex hormonal profile, semen analysis, sperm functional integrity, and seminal lipid peroxidation levels were assessed. The surgery resulted in BMI reduction and improvement in seminal characteristics and male sex hormone profile. The semen analysis showed increases in volume, sperm progressive motility, and in sperm morphology and a decrease in immotile sperms. Sperm mitochondrial activity and sperm DNA integrity were improved, and the levels of seminal lipid peroxidation were decreased. The hormonal profile showed lower levels of estradiol and highest levels of luteinizing hormone (LH), sex hormone-binding globulin (SHBG), and testosterone. BMI changes resulting from this treatment and its metabolic consequences can be associated with changes in the male fertile potential, leading to an improvement in the seminal quality, male sex hormone profile, sperm functional aspects, and levels of seminal lipid peroxidation, thus decreasing the testicular oxidative stress.

The Vehicle Determines the Destination: The Significance of Seminal Plasma Factors for Male Fertility.

Of all human infertility cases, up to 50% show contributing factors leading to defects in the male reproductive physiology. Seminal plasma (SP) is the biological fluid derived from the male accessory sex gland which carries spermatozoa passing throughout the male and female reproductive tract during ejaculation. It contains a complicated set of heterogeneous molecular structures, including proteins, cell-free nucleic acid (DNA, microRNA and LncRNA), and small-molecule metabolites as well as inorganic chemicals (ions). For a long time, the substantial significance of seminal plasma factors’ functions has been underestimated, which is restricted to spermatozoa transport and protection. Notably, significant advancements have been made in dissecting seminal plasma components, revealing new insights into multiple aspects of sperm function, as well as fertilization and pregnancy outcomes in recent years. In this review, we summarize the state-of-art discoveries regarding SP compositions and their implications in male fertility, particularly describing the novel understanding of seminal plasma components and related modifications using “omics” approaches and mainly focusing on proteome and RNA-seq data in the latest decade. Meanwhile, we highlighted the proposed mechanism of the regulation of SP molecules on immunomodulation in the female reproductive tract. Moreover, we also discussed the proteins investigated as non-invasive diagnosis biomarkers for male infertility in the clinic.

Impact of oxidative stress on male and female germ cells: implications for fertility.

Male and female germ lines are vulnerable to oxidative stress. In spermatozoa, such stress triggers a lipid peroxidation cascade that culminates in the generation of electrophilic lipid aldehydes that bind to DNA and a raft of proteins involved in the delivery of functionally competent cells. One set of targets for these aldehydes are the proteins of the mitochondrial electron transport chain. When this interaction occurs, mitochondrial ROS generation is enhanced leading to the sustained generation of oxidative damage in a self-perpetuating cycle. Such damage affects all aspects of sperm function including motility, sperm-egg recognition, acrosomal exocytosis and sperm-oocyte fusion. Oxidative stress in the male germ line also attacks the integrity of sperm DNA with potential impacts on the developmental capacity of embryos and the health and wellbeing of the offspring. Potential pathways of reactive oxygen species (ROS) generation in male germ cells could involve enhanced lipoxygenase activity, activation of NADPH oxidase and/or electron leakage from mitochondria. Similarly, in the female germ line, both the induction of oocyte senescence following ovulation and the deterioration of oocyte quality with maternal age appear to involve the generation of oxidative damage. In this case, the mitochondria appear to be a particularly important source of ROS compromising the viability and fertilizability of the oocyte and interfering with the normal segregation of chromosomes during meiosis. In light of these considerations, antioxidants should have some role to play in the preservation of reproductive function in both men and women; however, we still await appropriate trials to test this hypothesis.

Signaling Enzymes Required for Sperm Maturation and Fertilization in Mammals.

In mammals, motility and fertilizing ability of spermatozoa develop during their passage through the epididymis. After ejaculation, sperm undergo capacitation and hyperactivation in the female reproductive tract – a motility transition that is required for sperm penetration of the egg. Both epididymal initiation of sperm motility and hyperactivation are essential for male fertility. Motility initiation in the epididymis and sperm hyperactivation involve changes in metabolism, cAMP (cyclic adenosine mono-phosphate), calcium and pH acting through protein kinases and phosphatases. Despite this knowledge, we still do not understand, in biochemical terms, how sperm acquire motility in the epididymis and how motility is altered in the female reproductive tract. Recent data show that the sperm specific protein phosphatase PP1γ2, glycogen synthase kinase 3 (GSK3), and the calcium regulated phosphatase calcineurin (PP2B), are involved in epididymal sperm maturation. The protein phosphatase PP1γ2 is present only in testis and sperm in mammals. PP1γ2 has a isoform-specific requirement for normal function of mammalian sperm. Sperm PP1γ2 is regulated by three proteins – inhibitor 2, inhibitor 3 and SDS22. Changes in phosphorylation of these three inhibitors and their binding to PP1γ2 are involved in initiation and activation of sperm motility. The inhibitors are phosphorylated by protein kinases, one of which is GSK3. The isoform GSK3α is essential for epididymal sperm maturation and fertility. Calcium levels dramatically decrease during sperm maturation and initiation of motility suggesting that the calcium activated sperm phosphatase (PP2B) activity also decreases. Loss of PP2B results in male infertility due to impaired sperm maturation in the epididymis. Thus the three signaling enzymes PP1γ2, GSK3, and PP2B along with the documented PKA (protein kinase A) have key roles in sperm maturation and hyperactivation. Significantly, all these four signaling enzymes are present as specific isoforms only in placental mammals, a testimony to their essential roles in the unique aspects of sperm function in mammals. These findings should lead to a better biochemical understanding of the basis of male infertility and should lead to novel approaches to a male contraception and managed reproduction.

Sperm functional aspects and enriched proteomic pathways of seminal plasma of adult men with obesity.

Previous studies have demonstrated an association between obesity and the decreased male fertility. to observe the mechanisms by which obesity affects semen quality. A prospective study was performed including 47 male volunteers, of which 27 were obese group (body mass index >30kg/m2 ) and 20 were eutrophic (body mass index between 18.5 and 25kg/m2 ) controls. Sperm functional analysis was performed. The remaining seminal plasma was pooled-four pools per group- and submitted to proteomic analysis by liquid chromatography coupled to tandem mass spectrometry. Groups were compared by an unpaired Student's t-test. Differentially expressed proteins were submitted to functional enrichment analysis using the online platform PantherDB. Obese men presented decreased non-progressive motility, morphology, acrosome integrity, mitochondrial activity, and increased sperm DNA fragmentation. In proteomics analysis, 69 proteins were differentially expressed between the two groups. Among them, one protein was absent, 19 were down-regulated, 49 were up-regulated, and one was exclusive in the study group. The main functions enriched were as follows: negative regulation of the intrinsic pathway of apoptosis, activation of immune and inflammatory, antioxidant activity, among others. molecular pathways suggest there is a causative link, and that the effector mechanisms alter sperm metabolic status and defective testicular selection 5 mechanisms.

CRISP2 Is a Regulator of Multiple Aspects of Sperm Function and Male Fertility.

The cysteine-rich secretory proteins (CRISPs) are a group of proteins that show a pronounced expression biased to the male reproductive tract. Although sperm encounter CRISPs at virtually all phases of sperm development and maturation, CRISP2 is the sole CRISP produced during spermatogenesis, wherein it is incorporated into the developing sperm head and tail. In this study we tested the necessity for CRISP2 in male fertility using Crisp2 loss-of-function mouse models. In doing so, we revealed a role for CRISP2 in establishing the ability of sperm to undergo the acrosome reaction and in establishing a normal flagellum waveform. Crisp2-deficient sperm possess a stiff midpiece and are thus unable to manifest the rapid form of progressive motility seen in wild type sperm. As a consequence, Crisp2-deficient males are subfertile. Furthermore, a yeast two-hybrid screen and immunoprecipitation studies reveal that CRISP2 can bind to the CATSPER1 subunit of the Catsper ion channel, which is necessary for normal sperm motility. Collectively, these data define CRISP2 as a determinant of male fertility and explain previous clinical associations between human CRISP2 expression and fertility.

Effect of orchiectomy on sperm functional aspects and semen oxidative stress in men with testicular tumours.

To verify if quality of spermatozoa from men with testicular germ cell tumours is better before or after orchiectomy. This prospective study was carried out including 24 patients with testicular germ cell tumours, who provide one semen sample before they were submitted to unilateral orchiectomy and one other semen sample 30days after the surgery. After collection by masturbation and liquefaction, an aliquot of the semen sample was used for semen analysis and another was used to evaluate sperm mitochondrial activity, DNA fragmentation and acrosome integrity. Seminal plasma was used to evaluate lipid peroxidation levels. Pre-orchiectomy sample and post-orchiectomy sample were compared using a paired Student's t test (normal distribution) or a paired Wilcoxon test, when appropriate (p˂0.05). No significant difference was observed in semen analysis. A significant decrease in DNA fragmentation and lipid peroxidation and an increase in mitochondrial activity were observed after orchiectomy. Based on our findings, the semen quality from men with testicular germ cell tumours is better after orchiectomy.

The functional anatomy of the human spermatozoon: relating ultrastructure and function.

The Internet, magazine articles, and even biomedical journal articles, are full of cartoons of spermatozoa that bear minimal resemblance to real spermatozoa, especially human spermatozoa, and this had led to many misconceptions about what spermatozoa look like and how they are constituted. This review summarizes the historical and current state of knowledge of mammalian sperm ultrastructure, with particular emphasis on and relevance to human spermatozoa, combining information obtained from a variety of electron microscopic (EM) techniques. Available information on the composition and configuration of the various ultrastructural components of the spermatozoon has been related to their mechanistic purpose and roles in the primary aspects of sperm function and fertilization: motility, hyperactivation, capacitation, the acrosome reaction and sperm-oocyte fusion.

Caenorhabditis elegans sperm membrane protein interactome.

The interaction and organization of proteins in the sperm membrane are important for all aspects of sperm function. We have determined the interactions between 12 known mutationally defined and cloned sperm membrane proteins in a model system for reproduction, the nematode Caenorhabditis elegans. Identification of the interactions between sperm membrane proteins will improve our understanding of and ability to characterize defects in sperm function. To identify interacting proteins, we conducted a split-ubiquitin membrane yeast two-hybrid analysis of gene products identified through genetic screens that are necessary for sperm function and predicted to encode transmembrane proteins. Our analysis revealed novel interactions between sperm membrane proteins known to have roles in spermatogenesis, spermiogenesis, and fertilization. For example, we found that a protein known to play a role in sperm function during fertilization, SPE-38 (a predicted four pass transmembrane protein), interacts with proteins necessary for spermiogenesis and spermatogenesis and could serve as a central organizing protein in the plasma membrane. These novel interaction pairings will provide the foundation for investigating previously unrealized membrane protein interactions during spermatogenesis, spermiogenesis, and sperm function during fertilization.

In vitro effects of endosulfan-based insecticides on mammalian sperm.

Endosulfan is an organochloride insecticide extensively used in several countries to protect crops from pests. As several studies indicate that endosulfan can affect human and animal development, the aim of this study was to analyse whether sperm parameters and the process of chromatin decondensation could be altered by endosulfan in mice sperm. Spermatozoa from cauda epididymis were obtained from mature male mice and incubated in the presence of two commercial formulations (CFs) of endosulfan (Master® and Zebra Ciagro®) or the active ingredient (AI) alone. A significant decrease in the percentage motility and viability of spermatozoa with respect to controls was found. In vitro decondensation was performed in the presence of glutathione and heparin. Spermatozoa incubated with the AI, endosulfan Master® and endosulfan Zebra Ciagro® showed an increase in chromatin decondensation. In addition, the TUNEL assay showed that DNA fragmentation was significantly higher when sperm were incubated with either one of the CFs when compared to the AI or controls. The ultrastructure analysis of sperm cells showed evident changes in the structure of the plasma and acrosome membranes of sperm incubated with endosulfan AI or the CFs. These results suggest that endosulfan can affect sperm integrity and in vitro chromatin decondensation as well as DNA fragmentation.

Introduction: Varicoceles: a contemporary perspective

In this Views and Reviews section, four groups of authors address the timely and highly relevant issue of varicoceles across the male life spectrum. Varicoceles are very prevalent among men presenting for an infertility workup. While reduction in bulk semen parameters (including sperm concentration, motility, and morphology) has long been recognized as a deficit caused by varicoceles, in recent years a number of investigators have shown that varicoceles can have broader, multi-faceted effects on male reproductive health. Sperm DNA integrity and other aspects of sperm function appear to be impacted by the presence of varicoceles, and varicocele correction can result in significant improvement in not only semen parameters, but also fertilization and pregnancy rates.

Sperm Affects Head Sensory Neuron in Temperature Tolerance of Caenorhabditis elegans.

Tolerance to environmental temperature change is essential for the survival and proliferation of animals. The process is controlled by various body tissues, but the orchestration of activity within the tissue network has not been elucidated in detail. Here, we show that sperm affects the activity of temperature-sensing neurons (ASJ) that control cold tolerance in Caenorhabditis elegans. Genetic impairment of sperm caused abnormal cold tolerance, which was unexpectedly restored by impairment of temperature signaling in ASJ neurons. Calcium imaging revealed that ASJ neuronal activity in response to temperature was decreased in sperm mutant gsp-4 with impaired protein phosphatase 1 and rescued by expressing gsp-4 in sperm. Genetic analysis revealed a feedback network in which ASJ neuronal activity regulates the intestine through insulin and a steroid hormone, which then affects sperm and, in turn, controls ASJ neuronal activity. Thus, we propose that feedback between sperm and a sensory neuron mediating temperature tolerance.

Diagnosis and prognosis of male infertility in mammal: the focusing of tyrosine phosphorylation and phosphotyrosine proteins.

Male infertility refers to the inability of a man to achieve a pregnancy in a fertile female. In more than one-third of cases, infertility arises due to the male factor. Therefore, developing strategies for the diagnosis and prognosis of male infertility is critical. Simultaneously, a satisfactory model for the cellular mechanisms that regulate normal sperm function must be established. In this regard, tyrosine phosphorylation is one of the most common mechanisms through which several signal transduction pathways are adjusted in spermatozoa. It regulates the various aspects of sperm function, for example, motility, hyperactivation, capacitation, the acrosome reaction, fertilization, and beyond. Several recent large-scale studies have identified the proteins that are phosphorylated in spermatozoa to acquire fertilization competence. However, most of these studies are basal and have not presented an overall mechanism through which tyrosine phosphorylation regulates male infertility. In this review, we focus of this mechanism, discussing most of the tyrosine-phosphorylated proteins in spermatozoa that have been identified to date. We categorized tyrosine-phosphorylated proteins in spermatozoa that regulate male infertility using MedScan Reader (v5.0) and Pathway Studio (v9.0).

Mitochondria functionality and sperm quality

Although mitochondria are best known for being the eukaryotic cell powerhouses, these organelles participate in various cellular functions besides ATP production, such as calcium homoeostasis, generation of reactive oxygen species (ROS), the intrinsic apoptotic pathway and steroid hormone biosynthesis. The aim of this review was to discuss the putative roles of mitochondria in mammalian sperm function and how they may relate to sperm quality and fertilisation ability, particularly in humans. Although paternal mitochondria are degraded inside the zygote, sperm mitochondrial functionality seems to be critical for fertilisation. Indeed, changes in mitochondrial integrity/functionality, namely defects in mitochondrial ultrastructure or in the mitochondrial genome, transcriptome or proteome, as well as low mitochondrial membrane potential or altered oxygen consumption, have been correlated with loss of sperm function (particularly with decreased motility). Results from genetically engineered mouse models also confirmed this trend. On the other hand, increasing evidence suggests that mitochondria derived ATP is not crucial for sperm motility and that glycolysis may be the main ATP supplier for this particular aspect of sperm function. However, there are contradictory data in the literature regarding sperm bioenergetics. The relevance of sperm mitochondria may thus be associated with their role in other physiological features, particularly with the production of ROS, which in controlled levels are needed for proper sperm function. Sperm mitochondria may also serve as intracellular Ca²⁺ stores, although their role in signalling is still unclear.

Cryopreservation of Greenshell™ Mussel (Perna canaliculus) sperm. II. Effect of cryopreservation on fertility, motility, viability and chromatin integrity

The effect of cryopreservation on aspects of sperm function was investigated for sperm of the Greenshell™ mussel (Perna canaliculus). Fertility, DNA integrity, viability and motility were measured before and after cryopreservation. Cryopreservation had a significant effect on fertility with many cryopreserved samples failing to achieve 50% oocyte fertilisation at the highest sperm concentration measured. Sperm DNA integrity, measured using the Sperm Chromatin Structure Assay, showed a small but significant increase in DNA damage as a result of cryopreservation. Sperm viability, measured using propidium iodide/SYBR-14 dual staining, decreased significantly following cryopreservation (69.9±3.5% for fresh sperm versus 25.3±2.9% for cryopreserved sperm). Aspects of motility were similarly affected. The number of sperm tracked, curvilinear velocity (VCL), average path velocity (VAP), variation of straight line velocity (PFT), mean angular displacement (MAD), beat cross frequency (BCF), amplitude of lateral head displacement (ALH) and dance mean (DMN) all decreased following cryopreservation. Correlation analyses between the various aspects of sperm function were carried out. However, no single aspect of sperm function was significantly correlated with sperm fertility following cryopreservation. In addition, the technique for fertility measurement is relatively quicker and less dependent on high tech equipment than the other parameters studied. Fertility therefore remains the most important and relevant end point to measure. Further optimisation of the cryopreservation protocol for Greenshell™ mussel sperm is needed to improve post-thaw fertility.

Sequential analysis of sperm functional aspects involved in fertilisation: a pilot study

The development of diagnostic techniques in andrology as a second level of approach to the diagnosis of male factor infertility has enthused the focus of researchers on the development of a sequential diagnostic programme for these men. Semen samples of 78 men form couples undergoing in vitro fertilisation therapy were used in the study. The semen samples were used to test sperm functional aspects known to interfere with fertilisation. These tests included semen profile, DNA integrity, apoptosis, chromatin packaging, acridin orange staining, zona binding capacity, zona-induced acrosome reaction (AR). Results were correlated with fertilisation outcome. Statistical analyses of the recorded data were carried out using a logistic regression analysis model on all sperm functional tests. A negative and significant association with the fertilisation rates was recorded for DNA damage (r = -0.56; P ≤ 0.0005). A positive significant correlation was recorded between fertilisation rates and sperm with normal DNA (r = -0.57, P ≤ 0.0004), and zona-induced AR (r = 0.33, P ≤ 0.002). Diagnostic andrology can be regarded as a mandatory part of the male factor patient's work-up schedule to assist clinicians with the most suitable therapeutic modality to follow.

2019 EFFECT OF MICROSURGICAL VARICOCELECTOMY ON HUMAN SPERM DNA INTEGRITY AND CHROMATIN COMPACTION

You have accessJournal of UrologyInfertility: Physiology, Pathophysiology, Basic Research1 Apr 20112019 EFFECT OF MICROSURGICAL VARICOCELECTOMY ON HUMAN SPERM DNA INTEGRITY AND CHROMATIN COMPACTION Naif Alhathal, Maria San Gabriel, and Armand Zini Naif AlhathalNaif Alhathal Montreal, Canada More articles by this author , Maria San GabrielMaria San Gabriel Montreal, Canada More articles by this author , and Armand ZiniArmand Zini Montreal, Canada More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2247AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Human sperm DNA damage may adversely affect reproductive outcomes, and the spermatozoa of infertile men possess substantially more DNA damage than that of fertile men. Further to our previous study on the effect of varicocelectomy on sperm DNA integrity (DFI= DNA fragmentation index) using sperm chromatin structure assay (SCSA), the objective of this study was to further assess human sperm chromatin integrity before and after varicocelectomy by evaluating aniline blue staining (AB) in these samples. METHODS We evaluated 20 men who underwent microsurgical varicocelectomy for clinical varicocele and 6 controls (sperm donors) at our institution. We examined standard semen parameters, sperm DNA integrity (by SCSA) and chromatin integrity (by aniline blue stain) before and after varicocelectomy and for the control group. RESULTS The percentage of sperm with positive AB staining (histone retention) decreased significantly after surgery (from 13.5 to 5.4%). The %DFI (DNA fragmentation index) also decreased significantly (as previously shown). However, there were no significant relationship between AB staining and %DFI, motility or concentration. The only notable relationship was between AB staining and HDS (high DNA stainability–an index of chromatin compaction) post varicocelectomy. Furthermore, the percentage of sperm with positive AB staining was significantly less in the control compared to varicocele patients before surgery (2.5% vs 13.5%). The %DFI also was significantly less in the control group (7% vs 20%). CONCLUSIONS The data show that varicocelectomy is associated with a consistent improvement in sperm DNA integrity and chromatin compaction using two different assays of sperm chromatin integrity (SCSA, Aniline Blue). However, the poor relationship between SCSA parameters (e.g. %DFI) and AB staining suggests that these assays measure different aspects of sperm function. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e807 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Naif Alhathal Montreal, Canada More articles by this author Maria San Gabriel Montreal, Canada More articles by this author Armand Zini Montreal, Canada More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...