Pathogenic variants of ATG4D in infertile men with non-obstructive azoospermia identified using whole-exome sequencing.

Non-obstructive azoospermia (NOA) is the most severe form of male infertility, and it is primarily associated with genetic defects. We performed whole-exome sequencing of 236 patients with NOA and identified a homozygous pathogenic variant of autophagy-related 4D cysteine peptidase (ATG4D) in two siblings from a consanguineous family and compound heterozygous pathogenic variants of ATG4D in two sporadic cases. The expression of LC3B, a regulator of autophagic activity, was significantly decreased, and the apoptosis rate of spermatogenic cells in testicular tissues was increased. Transfection of GC-2spd cells with a ATG4D mutant plasmid (Flag-Atg4dmut ) significantly decreased the expression level of Lc3b and increased the rate of apoptosis. Moreover, a pathogenic variant in X-linked ATG4A and compound heterozygous pathogenic variants of ATG4B were identified in one patient each. All novel variants were segregated by disease phenotype and were predicted to be pathogenic. Our findings revealed that autophagy-related cysteine peptidase family genes may play crucial roles in human spermatogenesis and identified ATG4D as a novel candidate gene for male infertility due to NOA.

Testicular steroid sulfatase overexpression is associated with Leydig cell dysfunction in primary spermatogenic failure.

BACKGROUND: Decreased testosterone (T) to LH ratio and increased 17ß-estradiol (E2) serum concentrations represent a common finding among patients with severe spermatogenic failure, suggesting a concurrent Leydig cell steroidogenic dysfunction. Aromatase overexpression has been associated with increased serum and intratesticular E2 in these patients. However, it is unknown whether the sulfatase pathway contributes to the increased availability of active estrogens in patients with primary spermatogenic failure. OBJECTIVES: To assess estrogen sulfotransferase (SULT1E1) and steroid sulfatase (STS) mRNA abundance in testicular tissue of patients with Sertoli cell-only syndrome (SCOS) and normal tissues, its association with serum and intratesticular hormone levels, and to explore the mRNA and protein testicular localization of both enzymes. MATERIALS AND METHODS: Testicular tissues of 23 subjects with SCOS (cases) and 22 patients with obstructive azoospermia and normal spermatogenesis (controls) were obtained after biopsy. SULT1E1 and STS transcripts accumulation was quantified by RT-qPCR. For mRNA and protein localization, we performed RT-qPCR in Leydig cell clusters and seminiferous tubules isolated by laser-capture microdissection and immunofluorescence in testicular tissues. Serum and intratesticular hormones were measured by immunoradiometric assays. RESULTS: SULT1E1 mRNA accumulation was similar in both groups. The amount of STS mRNA was higher in cases (p = 0.007) and inversely correlated with T/LH ratio (r = -0.402; p = 0.02). Also, a near significant correlation was observed with intratesticular E2 (r = 0.329, p = 0.057), in agreement with higher intratesticular E2 in cases (p < 0.001). Strong STS immunoreaction was localized in the wall of small blood vessels but not in Leydig cells. Both SULT1E1 and STS mRNA abundance was similar in Leydig cell clusters and the tubular compartment, except for lower SUTL1E1 mRNA in the seminiferous tubules of SCOS patients (p = 0.001). CONCLUSIONS: Our results suggest that an unbalance of the STS/SULT1E1 pathway contributes to the testicular hyperestrogenic microenvironment in patients with primary spermatogenic failure and Leydig cell dysfunction.

Dual histone methyl reader ZCWPW1 facilitates repair of meiotic double strand breaks in male mice.

Meiotic crossovers result from homology-directed repair of DNA double-strand breaks (DSBs). Unlike yeast and plants, where DSBs are generated near gene promoters, in many vertebrates DSBs are enriched at hotspots determined by the DNA binding activity of the rapidly evolving zinc finger array of PRDM9 (PR domain zinc finger protein 9). PRDM9 subsequently catalyzes tri-methylation of lysine 4 and lysine 36 of Histone H3 in nearby nucleosomes. Here, we identify the dual histone methylation reader ZCWPW1, which is tightly co-expressed during spermatogenesis with Prdm9, as an essential meiotic recombination factor required for efficient repair of PRDM9-dependent DSBs and for pairing of homologous chromosomes in male mice. In sum, our results indicate that the evolution of a dual histone methylation writer/reader (PRDM9/ZCWPW1) system in vertebrates remodeled genetic recombination hotspot selection from an ancestral static pattern near genes towards a flexible pattern controlled by the rapidly evolving DNA binding activity of PRDM9.

Deletion of Ck2ß gene causes germ cell development arrest and azoospermia in male mice.

OBJECTIVES: In humans, non-obstructive azoospermia (NOA) is a major cause of male infertility. However, the aetiology of NOA is largely unknown. Previous studies reported that protein CK2ß was abundantly and broadly expressed in spermatogenic cells. Here, we investigate whether protein CK2ß participates in spermatogenesis. MATERIALS AND METHODS: In this study, we separated spermatogenic cells using STA-PUT velocity sedimentation, analysed the expression pattern of protein CK2ß by immunoblotting, specifically deleted Ck2ß gene in early-stage spermatogenic cells by crossing Ck2ßfl mice with Stra8-Cre+ mice and validated the knockout efficiency by quantitative RT-PCR and immunoblotting. The phenotypes of Ck2ßfl/Δ ;SCre+ mice were studied by immunohistochemistry and immunofluorescence. The molecular mechanisms of male germ cell development arrest were elucidated by immunoblotting and TUNEL assay. RESULTS: Ablation of Ck2ß gene triggered excessive germ cell apoptosis, germ cell development arrest, azoospermia and male infertility. Inactivation of Ck2ß gene caused distinctly reduced expression of Ck2α' gene and CK2α' protein. CONCLUSIONS: Ck2ß is a vital gene for germ cell survival and male fertility in mice.

The alteration of RhoA geranylgeranylation and Ras farnesylation breaks the integrity of the blood-testis barrier and results in hypospermatogenesis.

Non-obstructive azoospermia (NOA) severely affects male infertility, however, the deep mechanisms of this disease are rarely interpreted. In this study, we find that undifferentiated spermatogonial stem cells (SSCs) still exist in the basal compartment of the seminiferous tubules and the blood-testis barrier (BTB) formed by the interaction of neighbor Sertoli cells (SCs) is incomplete in NOA patients with spermatogenic maturation arrest. The adhesions between SCs and germ cells (GCs) are also broken in NOA patients. Meanwhile, the expression level of geranylgeranyl diphosphate synthase (Ggpps), a key enzyme in mevalonate metabolic pathway, is lower in NOA patients than that in obstructive azoospermia (OA) patients. After Ggpps deletion specifically in SCs, the mice are infertile and the phenotype of the SC-Ggpps-/- mice is similar to the NOA patients, where the BTB and the SC-GC adhesions are severely destroyed. Although SSCs are still found in the basal compartment of the seminiferous tubules, fewer mature spermatocyte and spermatid are found in SC-Ggpps-/- mice. Further examination suggests that the defect is mediated by the aberrant protein isoprenylation of RhoA and Ras family after Ggpps deletion. The exciting finding is that when the knockout mice are injected with berberine, the abnormal cell adhesions are ameliorated and spermatogenesis is partially restored. Our data suggest that the reconstruction of disrupted BTB is an effective treatment strategy for NOA patients with spermatogenic maturation arrest and hypospermatogenesis.

Azoospermic infertility is associated with altered expression of DNA repair genes.

Compelling evidence suggest that germs cells are predominantly sensitive to DNA damaging agents in comparison to other cells. High fidelity DNA repair in testicular cells thus becomes indispensable to preserve the genomic integrity for passing on to the progeny. Compromised DNA repair machinery in the testicular cells may result in impaired spermatogenesis and infertility. It remains unclear if the alterations in the expression of DNA repair genes correlate with azoospermia and male infertility. In the present study, 54 non-obstructive azoospermic infertile patients with hypospermatogenesis (HS, n = 26), maturation arrest (MA, n = 15), Sertoli cell only syndrome (SCOS, n = 13) and 14 controls with obstructive azoospermia, but normal spermatogenesis were recruited. Expression profiling of 84 DNA repair genes in testicular biopsy samples was performed using PCR array. Out of 84 genes, 27, 64 and 28 genes showed >5 fold down-regulation in the HS, MA and SCOS groups, respectively. On the basis of differential expression and their functional significance in spermatogenesis, ten genes (MSH2, BRIP1, CCNH, LIG4, MGMT, NTHL1, PMS1, DMC1, POLB and XPA) were selected for validation of transcript levels in a higher number of cases using RT-PCR, which corroborated the findings of array. Four genes (MSH2, LIG4, PMS1 and DMC1) were analyzed for protein levels using immunohistochemistry, which further validated the loss of DNA repair gene expression. Caspase-3 immunostaining showed that the loss of DNA repair correlated with increased testicular apoptosis in patients. Maturation arrest showed the highest apoptotic index with maximum number of downregulated genes. We conclude that the loss of DNA repair genes expression in testis correlates with increased apoptosis, azoospermia and infertility.

ADAMTS1 and ADAMTS5 metalloproteases produced by Sertoli cells: a potential diagnostic marker in azoospermia.

In this study, our aim was to detect protein levels of A Disintegrin and Metalloproteinase with Thrombospondin Motifs 1 and 5 (ADAMTS1 and ADAMTS5) proteases and to examine the effect of in vitro FSH supplementation on protease production in cultured Sertoli cells. The expression of metalloproteases, ADAMTS1, and ADAMTS5 were investigated in Sertoli cell cultures as well as in ejaculate of azoospermic men which then were compared with ejaculates of the fertile control group. A total of 15 azoospermic men, diagnosed as obstructive (OA, n = 5) and nonobstructive (NOA, n = 10) azoospermia were included in the study. ADAMTS1, ADAMTS5 and FSH receptors (FSHR) were found to be expressed 2.56, 2.10, and 2.66-fold less in Sertoli cells of NOA patients, than those of OA (p < 0.05). After rFSH was added onto Sertoli cell cultures of NOA patients, their expression did not increase significantly and did not reach to levels of control group. Evaluation of ejaculates revealed that the expression of ADAMTS1 and ADAMTS5 were insignificantly 1.03 and 1.1-fold higher in OA group (p > 0.05), respectively; however, in the NOA group, their expression were 1.70 and 1.96-fold lower, respectively, when compared with the fertile control group (p < 0.05) which was statistically significant. As a conclusion, the present study has revealed that insufficiency of ADAMTS1 and ADAMTS5 expression in Sertoli cells may have an important role in the etiology of male infertility. As expected due to low FSHR expression, rFSH response is impaired in NOA patients with relatively low ADAMTS expression response; therefore, such patients might hardly benefit from rFSH treatment. Further studies with larger cohorts may reveal ADAMTSs' potential use as a predictive marker for positive sperm retrieval in azoospermic patients who are scheduled to undergo testicular sperm extraction. Abbreviations: ADAM: A Disintegrin and Metalloproteinase; ADAMTS1 and ADAMTS5: A Disintegrin and Metalloproteinase with 10 Thrombospondin Motifs 1 and 5; ADAMTS: A Disintegrin and Metalloproteinase with Thrombospondin; ABP: androgen binding protein; CAMs: cell adhesion molecules; ECM: extracellular matrix; FSH: follicle stimulating hormone; FSHR: FSH receptors; HRP: horseradish peroxidase; MMP: matrix metalloproteinases; MP: metalloproteinases; NOA: nonobstructive azoospermia; OA: obstructive azoospermia; TIMP-1: tissue inhibitor of metalloproteinase-1.

Among seven testis-specific molecular markers, SPEM1 appears to have a significant clinical value for prediction of sperm retrieval in azoospermic men.

BACKGROUND: To achieve sperm retrieval in azoospermic men, predicting the success rate seems to be necessary. OBJECTIVES: In the present study we aimed to assess expression of seven molecular markers [ESX1, DAZ, DAZL (pre-meiotic markers), ZMYND15, PRM1, TNP1, and SPEM1 (post-meiotic markers)] to predict the success of sperm retrieval. MATERIALS AND METHODS: In this study, 63 azoospermic men [16 OA (obstructive azoospermia) and 47 NOA (nonobstructive azoospermia)] undergoing testicular tissue microdissection (micro-TESE) for intracytoplasmic sperm injection (ICSI). Expression levels of these target genes were determined by real-time reverse transcription polymerase chain reaction using the DDCt method, and efficacy of each gene was compared by receiver operating characteristic (ROC) curve analysis. RESULTS: Expression of post-meiotic transcripts significantly decreases in NOA and its subgroups (SCOS: Sertoli cell only syndrome, MA: maturation arrest, and HS: hypospermatogenesis) with spermatogenic failure compared to normal spermatogenesis (OA), with an exception of ZMYND15 for the HS group. These findings suggest the differential expression of the post-meiotic ZMYND15 marker is in accordance with histological findings and can discriminate HS from SCOS and MA. Post-meiotic markers were significantly reduced in negative vs. positive sperm retrieval groups. DISCUSSION AND CONCLUSION: Among the seven markers, SPEM1 had the best positive prediction power (96%) and negative prediction power (85%) at a 0.086 cutoff with the area under the curve (AUC) of 0.91 for receiver operating characteristic 4 (ROC) to predict the micro-TESE outcome.

[Clinical report of testicular hypoplasia combined with 21-hydroxylase deficiency].

OBJECTIVE To investigate the correlation of 21-hydroxylase deficiency (21-OHD) with male testicular dysplasia. METHODS Clinical data of 8 infertile males with congenital adrenal hyperplasia due to 21-OHD was retrospectively analyzed. In addition, potential mutations of the CYP21A2 gene was detected. RESULTS All patients were referred because of azoospermia or severe oligospermia and had small testis with averaged testicular volume of 6.1 mL. Three patients had testicular adrenal rest tumors. Endocrinologic examinations revealed low levels of leutinizing hormone and follicular stimulating hormone, normal or elevated testosterone, elevated progesterone, elevated or normal adrenocoticotropic hormone, and low or normal cortisol. All patients had adrenal cortical hyperplasia, 5 with adrenal adenoma, 1 case associated with bilateral adrenal myelolipoma. All patients were given glucocorticoid replacement therapy for 3 to 6 months, which successfully improved the seminal status of 6 patient and resulted pregnancies in 5 couples. Seven pathogenic mutations of the CYP21A2 gene among the 8 patients. CONCLUSION 21-OHD can cause testicular hypoplasia and spermatogenic failure. Glucocorticoids and operations can obtain good result and improve spermatogenesis. Our results have shown a good genotype/phenotype correlation in these cases. All patients have carried the p.Ile172Asn mutation, which is associated with simple virilizing form.

Blood and semen paraoxonase-arylesterase activities in normozoospermic and azoospermic men.

Paraoxonase and arylesterase enzymes are corner stones of antioxidant defence. We aimed to compare azoospermic infertile men and normozoospermic individuals with respect to total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), paraoxonase and arylesterase levels in the blood and seminal plasma. Two-hundred consecutive infertility patients and voluntarily participated were included. In the normozoospermic group, TAS, PON, arylesterase values were statistically significantly higher when compared with those in the azoospermic group, while lower TOS and OSI levels were observed in the blood and seminal plasma of azoospermic group. In the semen analyses of normozoospermic group, the correlation between semen volume, sperm concentration, sperm motility and morphology and TAS, TOS, OSI, PON and arylesterase values was examined. A negative correlation was determined between semen volume and OSI. Levels of serum oxidative parameters were higher in the azoospermic group relative to normozoospermic group, but antioxidant parameters were lower than those of the normozoospermic group. Oxidative stress performs an essential role in the aetiology of male infertility by negatively influencing sperm quality and function. Assessment of blood and seminal plasma oxidative profiles might be an important tool to better evaluation of sperm reproductive capacity and functional competence.

Delayed diagnosis of disorder of sex development (DSD) due to P450 oxidoreductase (POR) deficiency.

CASE PRESENTATION: A 36-year old man, operated on for cryptorchidism at the age of 8 years, was referred to the Outpatient Clinic of Reproductive Endocrinology for investigation of infertility. Clinical examination revealed ambiguous genitalia: penis 4-5 cm, testicular volume 2-3 ml, hypospadias, hypertrophic foreskin and scrotum bifida. Mild hypertension was confirmed. No skeletal malformations were detected. DESIGN: Hormonal and electrolytic determinations as well as semen analysis were conducted. PCR of the coding regions of 17-hydroxylase/17,20 lyase (P450c17) and of P450 oxidoreductase (POR) genes was also performed. RESULTS: Normal levels of electrolytes, low levels of androgens, high levels of gonadotropins and 17-hydroxyprogesterone as well as azoospermia were detected. Karyotype was shown to be 46,XY. Both hCG and ACTH stimulation significantly increased 17-hydroxyprogesterone with no increase in androgens. The diagnosis was congenital adrenal hyperplasia with apparent combined P450c17 and P450c21 deficiency due to mutations in the POR gene. Sequencing of the POR gene revealed: one deletion in exon 12 (Del 1696_1698delGTC >del531Valine) and one missense mutation in exon 7 (A259G) as well as two polymorphisms: rs1057868 (C/T A503V) and rs1057870 (G/A S572S) in exons 12 and 13, respectively. No nucleotide changes were detected in the 8 exons of P450c17. CONCLUSIONS: Molecular findings were consistent with the diagnosis of P450 oxidoreductase deficiency. Despite this severe deficiency, skeletal malformations simulating Antley-Bixler syndrome, which usually characterize the most severe forms, were not confirmed. This discrepancy could be attributed to the differential impact of a POR variant on each one of the P450 enzymes.

CHFR is important for the survival of male premeiotic germ cells.

DNA damage response is required for male fertility. DNA damage repair mediates recombination between homologous chromosomes in meiotic prophase, which is essential for proper chromosome segregation during meiotic division. Interestingly, some DNA damage response proteins are also required for the survival of premeiotic germ cells, but their roles in these cells are still unclear. CHFR was recently shown to participate in DNA damage response, but it remains to be established if CHFR is required for male fertility. In this study, we characterized Chfr knockout male mice and found that around 30% of them were infertile. The onset of spermatogenesis was delayed and there was significant increase in apoptosis in premeiotic germ cells. This resulted in complete loss of germ cells in testes in 3 months and azoospermia in these mice. We further demonstrated that ATM activation was compromised in the testes of these mice. Therefore, CHFR is important for the survival of male premeiotic germ cells, which is likely through maintaining genomic stability in spermatogonial stem cells.

A G-quadruplex DNA structure resolvase, RHAU, is essential for spermatogonia differentiation.

G-quadruplex (G4) DNA and G4 DNA resolvase are involved in a variety of biological processes. To understand the biological function of G4 DNA structures and their resolvases in spermatogenesis, we investigated the distribution of G4 structures in mouse testis and identified their alterations during spermatogenesis. Meanwhile, we studied the function of RNA helicase associated with AU-rich element (RHAU), a G4 DNA resolvase, in spermatogenesis with a germ-cell-specific knockout mouse model. The results showed that the ablation of RHAU in germ cells caused the increase of G4 structures and thus resulted in the decrease of spermatogonial differentiation. c-kit, a spermatogonia differentiation-related gene, contains two G4 DNA motifs on its promoter. We found its expression was significantly downregulated in RHAU conditional knockout testis. A further analysis demonstrated that RHAU directly bound to the G4 structures to activate c-kit expression. We concluded that RHAU regulates spermatogonia differentiation by promoting c-kit expression via directly binding to the G4 DNA motifs c-kit promoter.

The dynamic of the apical ectoplasmic specialization between spermatids and Sertoli cells: the case of the small GTPase Rap1.

Despite advances in assisted reproductive technologies, infertility remains a consistent health problem worldwide. Spermiation is the process through which mature spermatids detach from the supporting Sertoli cells and are released into the tubule lumen. Spermiation failure leads to lack of mature spermatozoa and, if not occasional, could result into azoospermia, major cause of male infertility in human population. Spermatids are led through their differentiation into spermatozoa by the apical ectoplasmic specialization (aES), a testis-specific, actin-based anchoring junction restricted to the Sertoli-spermatid interface. The aES helps spermatid movement across the seminiferous epithelium, promotes spermatid positioning, and prevents the release of immature spermatozoa. To accomplish its functions, aES needs to undergo tightly and timely regulated restructuring. Even if components of aES are partly known, the mechanism/s through which aES is regulated remains still elusive. In this review, we propose a model by which the small GTPase Rap1 could regulate aES assembly/remodelling. The characterization of key players in the dynamic of aES, such as Rap1, could open new possibility to develop prognostic, diagnostic, and therapeutic approaches for male patients under treatment for infertility as well as it could lead to the identification of new target for male contraception.

Next generation sequencing with copy number variant detection expands the phenotypic spectrum of HSD17B4-deficiency.

BACKGROUND: D-bifunctional protein deficiency, caused by recessive mutations in HSD17B4, is a severe, infantile-onset disorder of peroxisomal fatty acid oxidation. Few affected patients survive past two years of age. Compound heterozygous mutations in HSD17B4 have also been reported in two sisters diagnosed with Perrault syndrome (MIM # 233400), who presented in adolescence with ovarian dysgenesis, hearing loss, and ataxia. CASE PRESENTATION: An adult male presented with cerebellar ataxia, peripheral neuropathy, hearing loss, and azoospermia. The clinical presentation, in combination with biochemical findings in serum, urine, and muscle biopsy, suggested a mitochondrial disorder. Commercial genetic testing of 18 ataxia and mitochondrial disease genes was negative. Targeted exome sequencing followed by analysis of single nucleotide variants and small insertions/deletions failed to reveal a genetic basis of disease. Application of a computational algorithm to infer copy number variants (CNVs) from exome data revealed a heterozygous 12 kb deletion of exons 10-13 of HSD17B4 that was compounded with a rare missense variant (p.A196V) at a highly conserved residue. Retrospective review of patient records revealed mildly elevated ratios of pristanic:phytanic acid and arachidonic:docosahexaenoic acid, consistent with dysfunctional peroxisomal fatty acid oxidation. CONCLUSION: Our case expands the phenotypic spectrum of HSD17B4-deficiency, representing the first male case reported with infertility. Furthermore, it points to crosstalk between mitochondria and peroxisomes in HSD17B4-deficiency and Perrault syndrome.

Association of the gonadotrophin-regulated testicular RNA helicase gene polymorphism with human male infertility.

Gonadotrophin-regulated testicular RNA helicase (GRTH) plays an important role in RNA functions including nuclear transcription, pre-mRNA splicing and it regulates the translation of specific genes required for the progression of spermatogenesis. In this study, we analysed the association of GRTH gene IVS6+55G/T and c.852C/T polymorphisms with human male infertility. The study showed c.852 T allele was associated with an increased risk of male infertility (OR: 3.16, P = 0.008), whereas IVS6+55G/T allele conferred no risk. In Indian population, this is the first report on association of GRTH gene SNP polymorphism and male infertility and it underscores the significance of GRTH genotypes in modulating the risk of male infertility.

[Neutral alpha-glucosidase activity is correlated with the location of epididymal obstruction in azoospermia men].

OBJECTIVE: To evaluate the correlation of neutral alpha-glucosidase in seminal plasma with the location of epididymal obstruction in azoospermia men. METHODS: We detected neutral alpha-glucosidase activity in the seminal plasma of 59 men with obstructive azoospermia followed by determining the location of epididymal obstruction by scrotal exploratory surgery. Then we analyzed the correlation between neutral alpha-glucosidase and the location of epididymal obstructive azoospermia. RESULTS: Among the total number of patients, there were 25 cases of bilateral cauda epididymal obstruction, 15 bilateral corpus, 12 bilateral caput, 4 unilateral caput-opposite cauda, and 3 unilateral corpus-opposite cauda. The neutral alpha-glucosidase levels in the seminal plasma of bilateral cauda, corpus and capus epididymal obstructions were (4.1 +/- 1.9), (13.8 +/- 4.4) and (46.8 +/- 19.3) mU per ejaculate, respectively, with statistically significant differences among the three groups (P < 0.05). CONCLUSION: Neutral alpha-glucosidase activity is significantly correlated with the location of epididymal obstruction in azoospermia men, which helps to locate epididymal obstruction, evaluate surgical prognosis and reduce the time of scrotal exploratory surgery.

Genetic variants of eNOS gene may modify the susceptibility to idiopathic male infertility.

In testis, eNOS is responsible for synthesis of nitric oxide (NO) which is an essential gas message regulator in spermatogenesis, suggesting that eNOS gene plays a role in normal spermatogenesis and the genetic variants of eNOS gene may be potential genetic risk factors of spermatogenesis impairment. In this study, the polymorphic distributions of three common polymorphism loci including T-786C, 4A4B and G894T in eNOS gene were investigated in 355 Chinese infertile patients with azoospermia or oligozoospermia and 246 healthy fertile men and a meta-analysis was carried in order to explore the possible relationship between the three loci of eNOS gene and male infertility with spermatogenesis impairment. As a result, allele -786C of T-786C (11.4% versus 6.5%, p = 0.004) and 4A of 4A4B (11.0% versus 6.3%, p = 0.005) as well as genotype TC of T-786C (22.8% versus 13.0%, p = 0.002) and AB of 4A4B (18% versus 11%, p = 0.015) were significantly associated with idiopathic male infertility. The haplotypes T-4A-G (7.4% versus 4.1%, p = 0.015) and C-4B-G (7.6% versus 4.4%, p = 0.028) could increase the susceptibility to male infertility, whereas haplotype T-4B-G (67.0% versus 75.2%, p = 0.002) might be a protective factor for male infertility. The results of meta-analysis revealed that the polymorphism of T-786C was associated with male infertility. These findings suggested that the variants of eNOS gene may modify the susceptibility to male infertility with impaired spermatogenesis.

Caspase signalling pathways in human spermatogenesis.

PURPOSE: Little is known about the apoptotic mechanisms involved in abnormal spermatogenesis. In order to describe the significance of apoptosis in azoospermia, testicular tissue from abnormal spermatogenesis was analysed. METHODS: Testicular treatment biopsies were obtained from 27 men. Five presented oligozoospermia, 9 obstructive azoospermia (4 congenital bilateral absence of the vas deferens; 5 secondary azoospermia) and 13 non-obstructive azoospermia (5 hypospermatogenis; 3 maturation arrest; 5 Sertoli-cell-only syndrome). Immunohistochemical staining was performed for active caspases-3, -8 and -9. The presence of active caspases in Sertoli cells and germ cells was analyzed using stereological tools. RESULTS: Increased active caspase-3 was found in Sertoli-cell-only syndrome. No significant differences were found in maturation arrest. In hypospermatogenesis, primary spermatocytes were the germ cells with higher active caspases. Oligozoospermia and secondary obstruction showed significant differences among germ cells for the presence of all active caspases. In oligozoospermia, spermatogonia presented significant increased active caspase-9 in relation to active caspase-8. In primary obstruction and hypospermatogenesis, germ cells presented significant increased active caspases-3 and -9. CONCLUSIONS: Results suggest that increased active caspase-3 might be involved in Sertoli-cell-only syndrome etiology. In cases of hypospermatogenesis, intrinsic lesions at the meiotic stage seem to be related to the pathology. In secondary obstruction apoptosis is suggested to be initiated due to extrinsic and intrinsic lesions, whereas in primary obstruction only the intrinsic apoptotic pathway seems to be present. Finally, in oligozoospermic patients spermatogonia death by mitochondrial damage additionally to meiosis malfunctioning, might be on the origin of the decreased sperm output.

Prolidase enzyme activity in varicose venous walls related to sperm count in patients with varicocele.

OBJECTIVES: To investigate peripheral, seminal and varicose venous wall prolidase enzyme activities and their relationships between sperm parameters in patients with varicocele. DESIGN AND METHODS: Prolidase enzyme activities were determined in blood, seminal fluid and varicose vein walls in patients with grade 3 varicocele. Sperm parameters were also measured and the relationships between prolidase enzyme and sperm parameters were assessed by statistical correlation analysis. RESULTS: There was a significant and negative correlation between sperm counts and varicose venous wall prolidase enzyme activities (r = -0.618, p < 0.001) and a positive significant correlation between sperm counts and seminal fluid prolidase enzyme activities (r = 0.676, p < 0.001). None of the parameters were correlated with sperm motility indices. CONCLUSION: Varicose venous wall prolidase enzyme activity could be an important factor in progression of azoospermia and infertility in patients with varicocele.