Association between embryo morphokinetic development and intracytoplasmic sperm injection with epididymal sperm via time-lapse imaging.

The objective of this study was to investigate the impact of sperm source on embryo morphokinetics and the clinical outcomes of intracytoplasmic sperm injection (ICSI) cycles by considering the clustering of data (multiple embryos per patient that share a comparable developmental timing). This matched cohort study was performed at a private university-affiliated in vitro fertilization center. Women who underwent ICSI with epididymal sperm between January 2019 and December 2020 (the percutaneous epididymal sperm aspiration group, n = 32 cycles) were matched with women who underwent ICSI with ejaculated sperm because of idiopathic male factor infertility (the male factor infertility [MFI] group, n = 32 cycles) or female infertility (the control group, n = 32 cycles). Embryos were cultured in a time-lapse imaging incubator, and morphokinetic development was recorded and compared among the groups. Significantly slower divisions were observed in embryos derived from epididymal sperm than in those derived from the MFI and control groups. Embryos derived from epididymal sperm had a significantly lower KIDScore (3.1 ± 0.2) than did those derived from ejaculated spermatozoa from the MFI (5.4 ± 0.1) and control (5.6 ± 0.2, p < 0.001) groups. Epididymal sperm-derived embryos showed a significantly greater occurrence of multinucleation (23.2%) than did those derived from ejaculated sperm from the MFI and control groups (2.8% and 3.7%, p < 0.001, respectively). Epididymal sperm-derived embryos were significantly more likely to undergo direct or reverse cleavage (11.1%) than ejaculated sperm-derived embryos in the control group (4.3%, p = 0.001). In conclusion, delayed cell cleavage and increased incidences of blastomere multinucleation and abnormal cleavage patterns are observed when epididymal-derived sperm are used for ICSI.

Acute murine-betacoronavirus infection impairs testicular steroidogenesis and the quality of sperm production.

Although several testicular alterations promoted by coronavirus infection have been demonstrated, the extent, causes, and players of testicular pathogenesis are not totally understood. The present study aimed to investigate the short-term effects on male fertility of intranasally administered murine hepatitis virus strain 3 (MHV-3), a member of the genus Betacoronavirus, which causes a severe systemic acute infection. This mouse model might be used as a in vivo prototype for investigating the impact of betacoronavirus on the endocrine and exocrine testicular functions with the advantage to be performed in a biosafety level 2 condition. Herein, we performed virological, histopathological, and molecular studies regarding the testicular spermatogenesis and the spermatic quality analyses in an MHV-3-infected C57BL/6 mice. The main outcomes showed that MHV-3 infects mouse testis and induces a testicular inflammatory state, impairing the steroidogenic pathway. The infection led to several alterations in the testicular parenchyma, such as: seminiferous epithelium sloughing, retention of residual bodies, germ cell apoptosis, alterations in intercellular junction proteins, and worse spermatogenic parameters. Moreover, the levels of plasmatic testosterone as well as the quality of sperm production reduced. Therefore, the present data suggest that the viral/inflammatory impairment of the steroidogenic pathway and the consequent imbalance of androgen levels is critical in testicular pathology, disturbing the SC barrier function and the germ cell differentiation. Our study is important for comprehending the effects of beta coronavirus infections on testis function in order to develop treatments that could prevent virus-mediated male infertility.

Do aging, drinking, and having unhealthy weight have a synergistic impact on semen quality?

PURPOSE: To evaluate if age, alcohol consumption, and body mass index (BMI) have synergistic effects on seminal quality, and to rank these factors based on their impact on semen. METHODS: Retrospective study of 9464 patients attending an andrology laboratory. Data on patients' age and daily alcohol intake were provided by the patients. BMI was recorded in the laboratory. Seminal parameters evaluated were volume, sperm concentration and total count, motility, morphology, viability, nuclear maturity, and membrane functional integrity. RESULTS: All the seminal parameters evaluated were affected by the synergistic interaction Age x BMI, suggesting that this combination is more potent in affecting semen quality. The variables sperm morphology and nuclear maturity seemed to be especially susceptible since they were affected by the three synergistic interactions. In the logistic regression analysis, age was the most powerful factor since it impacted first on five of the nine parameters, impacting mainly on sperm motility, viability, and morphology, with no effects on sperm count. On the contrary, BMI impacted first in sperm concentration and total sperm count; which was confirmed also by the logistic predictions analysis. Alcohol consumption impacted first on membrane functional integrity and nuclear maturity. A J-shaped association between BMI or alcohol consumption with semen quality was found in the multivariate analysis. CONCLUSION: The factors considered in this study showed a synergistic negative impact on semen quality, being age and unhealthy weight the most important ones. Reducing the exposure to lifestyle risk factors may be promising for improving sperm quality in infertile patients.

Comparative transcriptomics between Drosophila mojavensis and D. arizonae reveals transgressive gene expression and underexpression of spermatogenesis-related genes in hybrid testes.

Interspecific hybridization is a stressful condition that can lead to sterility and/or inviability through improper gene regulation in Drosophila species with a high divergence time. However, the extent of these abnormalities in hybrids of recently diverging species is not well known. Some studies have shown that in Drosophila, the mechanisms of postzygotic isolation may evolve more rapidly in males than in females and that the degree of viability and sterility is associated with the genetic distance between species. Here, we used transcriptomic comparisons between two Drosophila mojavensis subspecies and D. arizonae (repleta group, Drosophila) and identified greater differential gene expression in testes than in ovaries. We tested the hypothesis that the severity of the interspecies hybrid phenotype is associated with the degree of gene misregulation. We showed limited gene misregulation in fertile females and an increase in the amount of misregulation in males with more severe sterile phenotypes (motile vs. amotile sperm). In addition, for these hybrids, we identified candidate genes that were mostly associated with spermatogenesis dysfunction.

Effect of varicocelectomy on sperm deoxyribonucleic acid fragmentation rates in infertile men with clinical varicocele: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the effect of varicocelectomy on sperm deoxyribonucleic acid fragmentation (SDF) rates in infertile men with clinical varicocele. DESIGN: Systematic review and meta-analysis. SETTING: Not applicable. PATIENT(S): Infertile men with clinical varicocele subjected to varicocelectomy. INTERVENTION(S): Systematic search using PubMed/Medline, EMBASE, Cochrane's central database, Scielo, and Google Scholar to identify relevant studies published from inception until January 2021. We included studies comparing SDF rates before and after varicocelectomy in infertile men with clinical varicocele. MAIN OUTCOME MEASURE(S): The primary outcome was the difference between the SDF rates before and after varicocelectomy. A meta-analysis of weighted data using random-effects models was performed. Results were reported as weighted mean differences (WMD) with 95% confidence intervals (CIs). Subgroup analyses were performed on the basis of the SDF assay, varicocelectomy technique, preoperative SDF levels, varicocele grade, follow-up time, and study design. RESULT(S): Nineteen studies involving 1,070 patients provided SDF data. Varicocelectomy was associated with reduced postoperative SDF rates (WMD -7.23%; 95% CI: -8.86 to -5.59; I2 = 91%). The treatment effect size was moderate (Cohen's d = 0.68; 95% CI: 0.77 to 0.60). The pooled results were consistent for studies using sperm chromatin structure assay, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling, sperm chromatin dispersion test, and microsurgical varicocele repair. Subgroup analyses showed that the treatment effect was more pronounced in men with elevated vs. normal preoperative SDF levels, but the impact of varicocele grade remained equivocal. Meta-regression analysis demonstrated that SDF decreased after varicocelectomy as a function of preoperative SDF levels (coefficient: 0.23; 95% CI: 0.07 to 0.39). CONCLUSION(S): We concluded that pooled results from studies including infertile men with clinical varicocele indicated that varicocelectomy reduced the SDF rates. The treatment effect was greater in men with elevated (vs. normal) preoperative SDF levels. Further research is required to determine the full clinical implications of SDF reduction for these men.

Leaf and Fruit Methanolic Extracts of Azadirachta indica Exhibit Antifertility Activity on Rats' Sperm Quality and Testicular Histology.

BACKGROUND: The world's population is still growing, having an impact on the environment and the economic growth of developing countries; so that, there is a particular interest in the development of new fertility control methods, focused on male contraception. OBJECTIVE: The objective of this study was to evaluate the effect of methanolic extracts of leaf and fruit of Azadirachta indica on sperm quality and testicular histology of Long Evans rats. METHODS: Antifertility effects of a methanolic leaf and fruit extracts of A. indica on 24 male rats were investigated. The animals were randomly divided into two control groups and four treatment groups (n=4). Doses of the leaf and fruit extract were given at concentrations of 100 and 200 µg mL-1. RESULTS: A significant decrease in the viability of sperm cells was observed. The leaf extract at a concentration of 200 µg mL-1 inhibited cell viability compared to the negative control (p< 0.001). The percentage of abnormal cells in leaf extract was shown in 100 and 200 µg mL-1, the conditions at which a higher percentage of morphological irregularities of observed (15% and 16% respectively). The results show that there was cellular detachment in the seminiferous epithelium in the experimental groups treated with methanolic extracts. Sperm death was observed without decreasing the number of sperm. CONCLUSION: The methanolic extracts of Azadirachta indica have a modulating effect on the spermatogenesis of experimental rats through sperm morphological alterations.

Partial-AZFc deletions in Chilean men with primary spermatogenic impairment: gene dosage and Y-chromosome haplogroups.

PURPOSE: To investigate the association of partial-AZFc deletions in Chilean men with primary spermatogenic failure and their testicular histopathological phenotypes, analyzing the contribution of DAZ dosage, CDY1 copies, and Y-chromosome haplogroups. SUBJECTS AND METHODS: We studied 479 Chilean men: 334 infertile patients with histological examination (233 cases with spermatogenic defects and 101 normal spermatogenesis, obstructive controls, OC), and 145 normozoospermic controls (NC). AZFc subdeletions were detected by single-tagged sequences and single nucleotide variants analysis. DAZ-copy number was quantified by real-time qPCR. Y-chromosome haplogroups (Y-hg) were hierarchically genotyped through 16 biallelic-markers. RESULTS: The prevalence of AZFc-partial deletions was increased in cases (6%) compared with NC (1.4%) (P = 0.035). There was no difference between 143 Sertoli-cell only syndrome, 35 maturation arrest, or 35 mix atrophy patients and controls. However, gr/gr deletions were more frequent in 16 subjects with hypospermatogenesis compared with NC (P = 0.003) and OC (P = 0.013). Y-hg R was the most prevalent (~ 50%), but decreased among gr/gr deletions (21%, P = 0.03). The prevalence of Y-hg M increased in cases versus controls, both in total and non-deleted men (3.9 and 3.7% versus 0.4%, P = 0.009 and P = 0.016, respectively). Among gr/gr deletions, Y-hg H increased compared with non-deleted men (14.3% versus 0.4%, P = 0.0047). CONCLUSION: Partial-AZFc deletions in a Chilean admixed population are associated with secretory azo/oligozoospermia and might have a role in the development of hypospermatogenesis. Low represented haplogroups, Y-hg M and Y-hg H, show an association with the occurrence of spermatogenic failure and gr/gr deletions respectively; however, additional studies are required.

1H NMR-based metabonomics for infertility diagnosis in men with varicocele.

PURPOSE: "Omics" techniques have been used to understand and to identify biomarkers of male infertility. We report on the first metabonomics models created to diagnose varicocele and infertility among men with varicocele. METHODS: We recruited 35 infertile men with varicocele (VI group), 21 fertile men with varicocele (VF group) and 24 fertile men without varicocele (C group). All men underwent standard semen analysis, scrotal duplex ultrasonography, and sexual hormone level measurement. Hydrogen-1 nuclear magnetic resonance (1H NMR) spectra of seminal plasma were used to create metabonomics models to discriminate between men with and without varicocele, and between fertile and infertile men with varicocele. RESULTS: Using the statistical formalisms partial least square discriminants analysis and genetic algorithm-based linear discriminant analysis (GA-LDA), we created two models that discriminated the three groups from each other with accuracy of 92.17%. We also created metabonomics models using orthogonal partial least square discriminants analysis and GA-LDA that discriminated VF group from VI group, with an accuracy of 94.64% and 100% respectively. We identified 19 metabolites that were important in group segregation: caprate, 2-hydroxy-3-methylvalerate, leucine, valine, 3-hydroxybutyrate, lactate, alanine, 4-aminobutyrate, isoleucine, citrate, methanol, glucose, glycosides, glycerol-3-phosphocoline, n-acetyltyrosine, glutamine, tyrosine, arginine, and uridine. CONCLUSIONS: 1HNMR-based metabonomics of seminal plasma can be used to create metabonomics models to discriminate between men with varicocele from those without varicocele, and between fertile men with varicocele from those infertile with varicocele. Furthermore, the most important metabolites for group segregation are involved in the oxidative stress caused by varicocele.

Efficacy of MLPA for detection of Y-chromosome microdeletions in infertile Brazilian patients.

PURPOSE: Worldwide publications follow the gold standard method-the polymerase chain reaction (PCR)-for detecting Y-chromosome microdeletions; however, markers are frequently variable between the studies. Can we detect the deletions by another molecular method with more genomic coverage? The Y chromosome harbors several different genes responsible for testicular development and spermatogenesis, and its repetitive conformation predisposes it to complex rearrangements that have clinical impact. Our aim was to evaluate a molecular diagnostic method, the Multiplex Ligand Probe-dependent Amplification (MLPA), which is also a valuable ancillary method for the identification of deletions, duplications, and rearrangements in a single and faster reaction, leading to a better comprehension of patients' phenotypes, and should be considered a useful tool for detection of Y chromosome deletions. METHODS: This is a study of diagnostic accuracy (transversal prospective study) conducted to investigate Y-chromosome deletions in 84 individuals through PCR and MLPA methods. Forty-three infertile men (azoospermic and oligozoospermic) and 41 controls (40 fertile men and 1 normal karyotyped woman) were analyzed by PCR and MLPA techniques. RESULTS: We diagnosed seven (7) deletions (16.2%) by PCR and 9 with MLPA (21%). In addition, we found five (5) duplications and a suggestive mosaic. CONCLUSION: Our results demonstrate that MLPA technique is valuable in the investigation of microdeletions and microduplications. Besides deletions, duplications can cause instability of chromosome genes, possibly leading to infertility. Both studied techniques provide an advantageous diagnostic strategy, thus enabling a better genetic counseling.

Seminal plasma protein networks and enriched functions in varicocele: Effect of smoking.

To verify a possible synergistic effect of smoking and varicocele on the seminal plasma proteome and biological functions, a cross-sectional study was performed in 25 smokers and 24 nonsmokers. Samples were used for conventional semen analysis, functional analysis (DNA fragmentation, acrosome integrity and mitochondrial activity) and proteomics by a shotgun approach. Functional enrichment of biological pathways was performed in differentially expressed proteins. Smokers presented lower ejaculate volume (p = .027), percentage of progressively motile spermatozoa (p = .002), total sperm count (p = .039), morphology (p = .001) and higher percentage of immotile spermatozoa (p = .03), round cell (p = .045) and neutrophil count (p = .009). Smokers also presented lower mitochondrial activity and acrosome integrity and higher DNA fragmentation. We identified and quantified 421 proteins in seminal plasma, of which one was exclusive, 21 were overexpressed and 70 were underexpressed in the seminal plasma of smokers. The proteins neprilysin, beta-defensin 106A and histone H4A were capable of predicting the smoker group. Enriched functions were related to immune function and sperm machinery in testis/epididymis. Based on our findings, we can conclude that cigarette smoking leads to the establishment of inflammatory protein pathways in the testis/epididymis in the presence of varicocele that seems to act in synergy with the toxic components of the cigarette.

Antioxidant effects of penicillamine against in vitro-induced oxidative stress in human spermatozoa.

Oxidative stress contributes importantly to the aetiology of male infertility, impairing sperm function. The protective effect of antioxidants on seminal parameters has been established, and the antioxidant penicillamine has shown beneficial effects; however, its protective effect on human spermatozoa exposed to oxidative stress has not been reported. The objective of this work was to evaluate the effect of penicillamine on human spermatozoa exposed in vitro to oxidative stress. First, the effect of penicillamine on spermatozoa from normozoospermic donors was evaluated. Then, the effect of penicillamine on spermatozoa exposed to oxidative stress induced separately by ionomycin and hydrogen peroxide (H2 O2 ) was analysed. An untreated control and a control treated only with the oxidative stress inducer were included. Reactive oxygen species (ROS) levels, viability, mitochondrial membrane potential (MMP) and motility were analysed. The results showed that penicillamine, added to the incubation medium, decreased the ROS levels induced by ionomycin and H2 O2 , and this effect was associated with better preservation of MMP, motility, and ATP levels. These results highlight the potential advantages of penicillamine supplementation of sperm culture medium, especially for semen samples with high ROS levels and also in circumstances where laboratory handling can cause an increase in ROS production.

Sperm DNA fragmentation: causes and identification.

Sperm DNA fragmentation is referred to as one of the main causes of male infertility. Failures in the protamination process, apoptosis and action of reactive oxygen species (ROS) are considered the most important causes of DNA fragmentation. Action of ROS or changes in sperm protamination would increase the susceptibility of sperm DNA to fragmentation. Routine semen analysis is unable to estimate sperm chromatin damage. Sperm DNA integrity influences sperm functional capability, therefore tests that measure sperm DNA fragmentation are important to assess fertility disorders. Actually, there is a considerable number of methods for assessing sperm DNA fragmentation and chromatin integrity, sperm chromatin stability assay (SCSA modified), sperm chromatin dispersion (SCD), comet assay, transferase dUTP nick end labelling (TUNEL); and protamine evaluation in sperm chromatin assay, such as toluidine blue, CMA3, protamine expression and evaluation of cysteine radicals. This review aims to describe the main causes of sperm DNA fragmentation and the tests commonly used to evaluate sperm DNA fragmentation.

The effects of cannabidiol on male reproductive system: A literature review.

Cannabidiol (CBD) is one of the most abundant phytocannabinoids present in the plant Cannabis sativa (marijuana). There have been several studies of CBD in the last few decades, mainly focused on its neuroprotective properties, particularly after the identification of the endocannabinoid system and its participation in the central nervous system. On the other hand, the peripheral effects of CBD, particularly on reproductive physiology, were also evidenced. A narrative review was conducted using the PubMed database to identify studies that analyzed the pharmacological effects of CBD on the male reproductive system of vertebrates and invertebrates. Thirty-two citations (in vivo and in vitro) were identified. Among the vertebrates, the studies were carried out with men, monkeys, rats and mice. Studies with invertebrates are centered exclusively on the sea urchin. The CBD treatment periods include mostly acute and subacute evaluations. Exposure to CBD is associated with a reduction in mammalian testis size, the number of germ and Sertoli cells in spermatogenesis, fertilization rates, and plasma concentrations of hypothalamic, pituitary and gonadal hormones. Moreover, chronic doses of CBD have impaired sexual behavior in mice. From the studies identified in this review, it is possible to conclude that CBD has negative effects on the reproductive system of males. However, knowledge is still limited, and additional research is required to elucidate fully the mechanisms of action, as well as the reversibility of CBD effects on the reproductive system.

Post-translational modifications of seminal proteins and their importance in male fertility potential.

Introduction: The seminal proteome has been shown to directly influence the male fertile potential. Post-translational modifications (PTMs) are significant changes that play a role in the biological regulation of proteins. Sperm cells are transcriptionally and translationally inactive and these modifications are essential to control protein function.Areas covered: Here we reviewed seven PTMs which importance for male reproductive function investigated in the past decade, namely S-nitrosylation and tyrosine nitration (both occurring by the action of NO), glycosylation, ubiquitination, acetylation, methylation, and SUMOylation. Since they were previously identified in human semen, we focus on their role in sperm function, as well as in physiological and pathophysiological processes which could contribute to the fertility potential. The following keywords were applied: 'post-translational modification', 'sperm', 'semen', 'seminal plasma', 'male infertility', 'nitrosylation', 'nitration', 'histone methylation', 'SUMOylation', 'ubiquitination', 'ubiquitilation', 'glycosylation', and 'acetylation'.Expert opinion: Most biological processes orchestrated by proteins require PTMs for their activation or inhibition. Most of them are dynamic and occur in mature sperm, modulating protein function, thus exerting a significant role in sperm function and fertility. Finally, the study of PTMs should be also addressed in pathophysiological processes, as different clinical conditions are known to alter the proteome.

In search of new paradigms for epididymal health and disease: innate immunity, inflammatory mediators, and steroid hormones.

The primary job of the epididymis is to mature and protect the luminally transiting spermatozoa. Mounting evidence is showing that innate immune components [including Toll-like receptors (TLRs) and antimicrobial proteins, among which are ß-defensins] and inflammatory mediators, under the primary influence of androgens, participate in the cellular and molecular processes that define this tissue. Here, we present an overview of the contributions of these signaling pathway components during epididymal homeostasis and discuss the hypotheses as to their involvement in epididymitis, the most common urological inflammatory condition in men, frequently impairing their fertility. Drawing primarily from rodent models, we also focus on how the distribution and functional expression of innate immune components are differentially regulated in the prenatal developing epididymis, providing new insights into the disruption of these signaling pathways throughout the lifespan. Male infertility is caused by a variety of conditions, such as congenital malformations, genetic and endocrine disorders, exposure to environmental toxicants, and inflammatory/infectious conditions. More than one-third of infertile men with an idiopathic condition cannot currently be adequately diagnosed. Thinking about the innate immunity and inflammation context of the epididymis may provide new insights and directions as to how these systems contribute to male fertility, as well as also uncover urological and andrological outcomes that may aid clinicians in diagnosing and preventing epididymal pathologies.

Testicular sperm extraction in men with sertoli cell-only testicular histology - 1680 cases.

OBJECTIVE: To study the outcomes of testicular sperm extraction (TESE) among men with pure Sertoli cell-only histology identified during diagnostic testicular biopsy. METHODS: This retrospective cohort study involved 1680 cases of patients with nonobstructive azoospermia (NOA) diagnosed with pure Sertoli cell-only histology who underwent testicular biopsy with TESE in a reference center in Brazil by a single surgeon. Sperm retrieval rates (SSR) were the main outcome measure. RESULTS: Overall, 14.83% of patients with Sertoli cell-only had sperm retrieved with TESE in quantity that allowed the performance of ICSI. No differences were observed in SSR based on testis volume (<15 mL vs. <15 mL) or serum FSH level. CONCLUSIONS: Patients with Sertoli cell-only histology can be counseled that they have some likelihood of sperm retrieval with TESE. Based on the findings, patients to be submitted to testicular biopsy for histologic analysis may be concomitantly prepared for ICSI with TESE in case sperm is available.

Cysteine-rich secretory protein 3: inflammation role in adult varicocoele.

BACKGROUND: Cysteine-rich secretory protein (CRISP-3), a protein involved in inflammatory response, is highly increased in seminal plasma of adolescents with varicocoele and altered semen analysis, but not in adolescents with varicocoele and normal semen. It is not known, however, whether this increased seminal concentration occurs as an acute marker during the initial stages of varicocoele or whether this persists as an altered protein pathway. OBJECTIVE: The purpose of this study, thus, was to test the hypothesis that this inflammatory state persists through adulthood and the correction of varicocoele could correct this state, by identifying the levels of CRISP-3 in seminal plasma. MATERIALS AND METHODS: This study was carried out in two substudies: (i) to verify the effect of varicocoele and (ii) to verify the effect of varicocelectomy on seminal plasma CRISP-3 levels. Seminal plasma CRISP-3 levels (29 and 31 kDa isoforms) were assessed for each provided sample using standard Western blotting. RESULTS: The varicocoele group presented higher seminal levels of CRISP-3 when compared to controls, with a 67.5-fold increase in the unglycosylated isoform (29 kDa) and a 5.2-fold increase in the glycosylated isoform (31 kDa). In contrast, CRISP-3 levels decreased following varicocelectomy, both in the unglycosylated (5.6-fold decrease) and in the glycosylated (4.3-fold decrease) isoforms. DISCUSSION: CRISP-3, a protein involved in inflammation, is increased in seminal plasma of men with varicocoele and this is partially reversed by varicocelectomy. Monitoring its seminal levels may be useful for assessing inflammation-related alterations to fertility in men with varicocoele. CONCLUSION: We conclude that, in the presence of varicocoele, there is a marked increase in seminal CRISP-3 levels. Surgical intervention (varicocelectomy) decreases CRISP-3 levels and improves semen quality.

Impaired male fertility and abnormal epididymal epithelium differentiation in mice lacking CRISP1 and CRISP4.

Epididymal Cysteine Rich Secretory Proteins 1 and 4 (CRISP1 and CRISP4) associate with sperm during maturation and play different roles in fertilization. However, males lacking each of these molecules individually are fertile, suggesting compensatory mechanisms between these homologous proteins. Based on this, in the present work, we generated double CRISP1/CRISP4 knockout (DKO) mice and examined their reproductive phenotype. Our data showed that the simultaneous lack of the two epididymal proteins results in clear fertility defects. Interestingly, whereas most of the animals exhibited specific sperm fertilizing ability defects supportive of the role of CRISP proteins in fertilization, one third of the males showed an unexpected epididymo-orchitis phenotype with altered levels of inflammatory molecules and non-viable sperm in the epididymis. Further analysis showed that DKO mice exhibited an immature epididymal epithelium and abnormal luminal pH, supporting these defects as likely responsible for the different phenotypes observed. These observations reveal that CRISP proteins are relevant for epididymal epithelium differentiation and male fertility, contributing to a better understanding of the fine-tuning mechanisms underlying sperm maturation and immunotolerance in the epididymis with clear implications for human epididymal physiology and pathology.

Implications of prostate inflammation on male fertility.

The prostate is the seat of three major causes of morbidity: benign prostatic hyperplasia, prostate cancer and prostatitis, three conditions in which inflammation has been implicated. A state of inflammation of the prostate gland, originally incited by an infection, an autoimmune response, a neurogenic stimulus or another trigger may have consequences on prostate functionality. In fact, male fertility depends intrinsically on the content of prostatic fluid factors secreted by the prostatic epithelium. Taking into account that the prostate gland is the major male accessory gland that exerts essential functions for male fertility, a state of local inflammation can alter male fertility by either directly impairing sperm quality or, indirectly, by causing prostate dysfunction. In the present review, we summarise the current knowledge regarding prostatitis due to well-known infections such as Escherichia coli, Chlamydia trachomatis and other commonly identified microorganisms focusing on inflammatory markers detected during these infections and seminal quality and male fertility alterations reported. We also focused on type III prostatitis or chronic nonbacterial prostatitis/chronic pelvic pain syndrome, of unknown aetiology, in which inflammation of an autoimmune origin, neurogenic stimuli or another trigger have been proposed and fertility alterations reported.