Diurnal variation of semen quality in human males. (41/2696)

The possibility of a diurnal variation in semen quality was tested in 54 human males attending our infertility clinic. Of the enrolled subjects, 24 were normozoospermic and 30 were suffering from oligo- and/or asthenozoospermia. Seminal fluid was collected by masturbation twice by each subject, once in the morning (7:00-7:30 a.m.) and once in the afternoon (5:00-5:30 p.m.). Abstinence from sexual intercourse for 3-4 days before each of the two collections was requested. Semen parameters were evaluated independently by two biologists before and after pellet swim-up. Beside similar macroscopic parameters, specimens collected in the afternoon showed a higher number (P < 0.01) and concentration (P < 0.01) of spermatozoa. Also, immediately (P < 0.05), and at 1 h (P < 0.02) and 2 h (P < 0.01) after pellet swim-up, the number of spermatozoa with progressive linear motility was higher in the afternoon than in the morning. These data are the first documenting a diurnal rhythm in sperm quality which may contribute to the reported variability in semen parameters, and may prove useful for spontaneous and assisted conceptions.  (+info)

Assisted reproduction for infertile patients with 9 + 0 immotile spermatozoa associated with autosomal dominant polycystic kidney disease. (42/2696)

We investigated the clinical feature of patients with totally immotile spermatozoa due to 9 + 0 ultrastructural flagellar defects and polycystic kidney disease. We also tried to establish the feasibility of applying modern assisted reproduction technology (ART) in these patients. During 6-year interval a total of 1956 Japanese men were referred to the male infertility clinic. Of them, 16 were diagnosed to have immotile spermatozoa and four of them exhibited axonemal 9 + 0 defects in the sperm flagella. These four also had autosomal dominant polycystic kidney disease (ADPKD). Intrauterine insemination (IUI) and conventional in-vitro fertilization and embryo transfer failed to achieve fertilization. Intracytoplasmic sperm injection (ICSI) with 100% immotile spermatozoa was performed in all four cases. Two-pronuclear fertilization was obtained in 27 of the 70 (38.6%) of the successfully injected oocytes, but no pregnancy resulted. In one case, a few motile spermatozoa were present at the second cycle of ICSI, a pregnancy was successfully achieved using these spermatozoa. While immotile spermatozoa from patients with the axonemal 9 + 0 defect achieved fertilization by ICSI, the embryos failed to develop. Our results indicate that the central microtubules may play a role in fetal development. Since the 4 patients with 9 + 0 defects also had ADPKD, the genetic linkage between these two conditions should be studied by molecular biological methods so as to aid our ability to counsel such patients.  (+info)

Morphology comparison of individually selected hyperactivated and non-hyperactivated human spermatozoa. (43/2696)

The objective of this study was to compare the morphology of human spermatozoa undergoing hyperactivated motility in vitro with those that were non-hyperactivated (non-hyp). Hyperactivation criteria were established by the Hobson Sperm Tracker (HST), sampling at 25 Hz, as curvilinear velocity (VCL) > or = 70 microns/s, amplitude of lateral head displacement (ALH) > or = 7 microns, linearity (LIN) < or = 30% and straight-line velocity (VSL) < or = 30 microns/s. Specially developed software incorporated in the HST produced a white computer-generated overlay for spermatozoa satisfying hyperactivation criteria. These spermatozoa, visually identified on a tracking monitor, were individually removed with micromanipulation equipment using a 12 microns-diameter needle. Fifty-six patient ejaculates were examined comprising a total morphological analysis of 1886 non-hyp spermatozoa and 1051 hyperactivated spermatozoa. Hyperactivated spermatozoa had a significantly higher mean percentage of normal heads and small acrosomes (P < 0.0001 and < 0.0001 respectively) and a significantly lower percentage of large and round heads, midpieces and tail defects (P = 0.002, < 0.0001, 0.02 and < 0.0001 respectively) when compared with non-hyp spermatozoa. These data demonstrate, for the first time, that a homogeneous live population of human hyperactivated spermatozoa, selected in vitro from patients with highly variable degrees of teratozoospermia, is comprised predominantly of cells with normal morphology (P < 0.0001).  (+info)

Reversion of the differentiated phenotype and maturation block in Sertoli cells in pathological human testis. (44/2696)

To study the relationship between abnormal Sertoli cell differentiation and spermatogenic impairment, we examined the expression of Sertoli cell markers normally lost at puberty, cytokeratin 18 (CK18), anti-Mullerian hormone (AMH) and M2A antigen, in three children (aged 1-2 years), 50 adults (aged 19-45 years) with obstructive or non-obstructive azoospermia or oligozoospermia, and six patients (aged 1-18 years) with 5 alpha-reductase deficiency. There was CK18 and/or AMH expression, but never M2A antigen expression, associated with spermatogonial arrest or Sertoli cell-only (SCO) syndrome in infertile men. Loss of M2A antigen suggests the transition of Sertoli cells to an adult phenotype, while CK18 and/or AMH expression may be a manifestation of de-differentiation of Sertoli cells. In 5 alpha-reductase deficiency, there was a sequential loss of CK18, M2A antigen and AMH around puberty, associated with partial spermatogenesis. The persistence of immature Sertoli cells expressing M2A antigen was associated with prepubertal seminiferous cords and SCO syndrome. Therefore, 5 alpha-reductase deficiency may prevent the maturation of Sertoli cells, resulting in impairment of spermatogenesis, and loss of M2A antigen expression coincides with a critical step in the Sertoli cell maturation. High follicle stimulating hormone concentrations due to failure of normal Sertoli cell differentiation indicate a normal development pattern of the hypothalamic-pituitary-gonadal axis.  (+info)

Human sperm proteome: immunodominant sperm surface antigens identified with sera from infertile men and women. (45/2696)

The objective of this study was to identify those immunodominant sperm antigens recognized by antisperm antibodies (ASA) in the serum samples of infertile men and women. High-resolution two-dimensional gel electrophoresis was employed to separate human sperm proteins using isoelectric focusing or nonequilibrium pH gradient electrophoresis, followed by PAGE. Serum samples from 15 infertile male subjects and 6 infertile female subjects that contained ASA as assayed by the immunobead binding test (IBT) were analyzed by Western blotting followed by enhanced chemiluminescence (ECL). Serum samples from 10 fertile subjects (5 males and 5 females) that were ASA negative by IBT were used as controls. The ECL blots were analyzed by computer scanning to compare the immunoreactivity between serum samples from fertile and infertile subjects and to identify the antigens unique to the sera of the infertile subjects; 98 sperm auto- and iso-antigenic protein spots were recognized by sera from infertile males and females but not from fertile subjects. Based on vectorial labeling with 125I at the sperm surface, a subset of 6 auto- and iso-antigens was identified as possibly relevant to antibody-mediated infertility.  (+info)

Mice carrying two t haplotypes: sperm populations with reduced Zona pellucida binding are deficient in capacitation. (46/2696)

Capacitation is the unique process by which mammalian sperm become capable of undergoing the acrosome reaction (AR). An approach to studying sperm capacitation is to identify mutations altering this process. Male mice carrying two t haplotypes are sterile, with poor sperm motility, reduced zona pellucida binding, and an inability to penetrate zona-free oocytes. The objective of this study was to examine sperm capacitation and its potential relationship to zona pellucida binding in mice of the same genetic strain carrying none, one, or two t haplotypes. Sperm capacitation was assessed by the B pattern of staining by chlortetracycline (CTC) and by the ability of sperm to undergo the lysophosphatidylcholine (LPC)-induced AR. The CTC assay demonstrated that sperm capacitation from t/+ mice was similar to that from +/+ mice, but sperm from t/t mice were deficient. LPC induced the AR of capacitated sperm, but not noncapacitated sperm, in a concentration-dependent manner. Sperm from t/t mice were also deficient in the LPC-induced AR. Thus, by two independent assays, sperm from t/t mice were shown to be deficient in capacitation. To determine whether a deficiency in capacitation could influence zona binding, the ability of capacitated versus noncapacitated sperm to bind to the zona pellucida was tested. The mean numbers of sperm bound per oocyte were significantly greater for capacitated sperm than for noncapacitated sperm. These results suggest that the deficient capacitation of sperm from t/t mice could be responsible for, or at least contribute to, their reduced ability to bind to the zona pellucida.  (+info)

Impairment of spermatogenesis in mice lacking a functional aromatase (cyp 19) gene. (47/2696)

It is well established that spermatogenesis is controlled by gonadotrophins and testosterone. However, a role for estrogens in male reproduction recently was suggested in adult mice deficient in estrogen receptor alpha. These mice became infertile primarily because of an interruption of fluid reabsorption by the efferent ductules of the epididymis, thus leading to a disruption of the seminiferous epithelium [Hess, R. A., Bunick, D., Lee, K. H., Bahr, J., Taylor, J. A., Korach, K. S., and Lubahn, D. B. (1997) Nature (London) 390, 509-512]. Despite the demonstration of the aromatase enzyme, which converts androgens to estrogens, and estrogen receptors within the rodent seminiferous epithelium, the role of aromatase and estrogen in germ cell development is unknown. We have investigated spermatogenesis in mice that lack aromatase because of the targeted disruption of the cyp19 gene (ArKO). Male mice deficient in aromatase were initially fertile but developed progressive infertility, until their ability to sire pups was severely impaired. The mice deficient in aromatase developed disruptions to spermatogenesis between 4.5 months and 1 year, despite no decreases in gonadotrophins or androgens. Spermatogenesis primarily was arrested at early spermiogenic stages, as characterized by an increase in apoptosis and the appearance of multinucleated cells, and there was a significant reduction in round and elongated spermatids, but no changes in Sertoli cells and earlier germ cells. In addition, Leydig cell hyperplasia/hypertrophy was evident, presumably as a consequence of increased circulating luteinizing hormone. Our findings indicate that local expression of aromatase is essential for spermatogenesis and provide evidence for a direct action of estrogen on male germ cell development and thus fertility.  (+info)

Screening for microdeletions of Y chromosome genes in patients undergoing intracytoplasmic sperm injection. (48/2696)

The potential of assisted reproduction techniques to transmit genetic defects causing male infertility raises questions concerning the need for a systematic genetic screen and counselling. Deletions of the long arm of the Y chromosome are frequently associated with a failure of spermatogenesis. The search for Y specific sequences and for the gene families RNA binding motif (RBM) and deleted in azoospermia (DAZ) have been introduced in many laboratories. The incidence of Y microdeletions varies widely between studies, from 1-55%. These differences are mainly related to study design. The highest incidence of microdeletions has been reported in well selected idiopathic azoospermic patients. Since microdeletions have been reported also in non-idiopathic patients, it is important to define what is the deletion frequency in unselected patients. We report Y chromosome microdeletion screening in 134 unselected patients undergoing intracytoplasmic sperm injection (ICSI). In the first part of the study we tested six Y chromosome markers. We found three patients with microdeletions (2.2%). Subdivision of the study population revealed a deletion incidence of 4.7% in azoospermic/cryptozoospermic patients; an incidence of 7% in idiopathic patients and an incidence of 16% in idiopathic azoospermic/cryptozoospermic patients. The second part of the study consisted of a screen for the presence of the Y chromosome genes, DBY, CDY, XKRY, eIF-1A, DAZ and BPY2. No additional gene-specific deletions were found. Further data on gene specific screening are needed especially for selected idiopathic patients.  (+info)