Azoospermia

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Beatrice Dorphin - One of the best experts on this subject based on the ideXlab platform.

  • SPINK2 deficiency causes infertility by inducing sperm defects in heterozygotes and Azoospermia inhomozygotes
    EMBO Molecular Medicine, 2017
    Co-Authors: Zine-eddine Kherraf, Marie Christou-kent, Thomas Karaouzene, Amir Amiri-yekta, Guillaume Martinez, Alexandra S. Vargas, Emeline Lambert, Christelle Borel, Beatrice Dorphin, Isabelle Aknin-seifer
    Abstract:

    Azoospermia, characterized by the absence of spermatozoa in the ejaculate, is a common cause of male infertility with a poorly characterized etiology. Exome sequencing analysis of two azoospermic brothers allowed the identification of a homozygous splice mutation in SPINK2, encoding a serine protease inhibitor believed to target acrosin, the main sperm acrosomal protease. In accord with these findings, we observed that homozygous Spink2 KO male mice had Azoospermia. Moreover, despite normal fertility, heterozygous male mice had a high rate of morphologically abnormal spermatozoa and a reduced sperm motility. Further analysis demonstrated that in the absence of Spink2, protease-induced stress initiates Golgi fragmentation and prevents acrosome biogenesis leading to spermatid differentiation arrest. We also observed a deleterious effect of acrosin overexpression in HEK cells, effect that was alleviated by SPINK2 coexpression confirming its role as acrosin inhibitor. These results demonstrate that SPINK2 is necessary to neutralize proteases during their cellular transit toward the acrosome and that its deficiency induces a pathological continuum ranging from oligoasthenoteratozoospermia in heterozygotes to Azoospermia in homozygotes.

  • spink2 deficiency causes infertility by inducing sperm defects in heterozygotes and Azoospermia in homozygotes
    Embo Molecular Medicine, 2017
    Co-Authors: Zine-eddine Kherraf, Thomas Karaouzene, Guillaume Martinez, Emeline Lambert, Christelle Borel, Marie Christoukent, Amir Amiriyekta, Alexandra Vargas, Beatrice Dorphin
    Abstract:

    Azoospermia, characterized by the absence of spermatozoa in the ejaculate, is a common cause of male infertility with a poorly characterized etiology. Exome sequencing analysis of two azoospermic brothers allowed the identification of a homozygous splice mutation in SPINK2, encoding a serine protease inhibitor believed to target acrosin, the main sperm acrosomal protease. In accord with these findings, we observed that homozygous Spink2 KO male mice had Azoospermia. Moreover, despite normal fertility, heterozygous male mice had a high rate of morphologically abnormal spermatozoa and a reduced sperm motility. Further analysis demonstrated that in the absence of Spink2, protease-induced stress initiates Golgi fragmentation and prevents acrosome biogenesis leading to spermatid differentiation arrest. We also observed a deleterious effect of acrosin overexpression in HEK cells, effect that was alleviated by SPINK2 coexpression confirming its role as acrosin inhibitor. These results demonstrate that SPINK2 is necessary to neutralize proteases during their cellular transit toward the acrosome and that its deficiency induces a pathological continuum ranging from oligoasthenoteratozoospermia in heterozygotes to Azoospermia in homozygotes.

Zine-eddine Kherraf - One of the best experts on this subject based on the ideXlab platform.

  • SPINK2 deficiency causes infertility by inducing sperm defects in heterozygotes and Azoospermia inhomozygotes
    EMBO Molecular Medicine, 2017
    Co-Authors: Zine-eddine Kherraf, Marie Christou-kent, Thomas Karaouzene, Amir Amiri-yekta, Guillaume Martinez, Alexandra S. Vargas, Emeline Lambert, Christelle Borel, Beatrice Dorphin, Isabelle Aknin-seifer
    Abstract:

    Azoospermia, characterized by the absence of spermatozoa in the ejaculate, is a common cause of male infertility with a poorly characterized etiology. Exome sequencing analysis of two azoospermic brothers allowed the identification of a homozygous splice mutation in SPINK2, encoding a serine protease inhibitor believed to target acrosin, the main sperm acrosomal protease. In accord with these findings, we observed that homozygous Spink2 KO male mice had Azoospermia. Moreover, despite normal fertility, heterozygous male mice had a high rate of morphologically abnormal spermatozoa and a reduced sperm motility. Further analysis demonstrated that in the absence of Spink2, protease-induced stress initiates Golgi fragmentation and prevents acrosome biogenesis leading to spermatid differentiation arrest. We also observed a deleterious effect of acrosin overexpression in HEK cells, effect that was alleviated by SPINK2 coexpression confirming its role as acrosin inhibitor. These results demonstrate that SPINK2 is necessary to neutralize proteases during their cellular transit toward the acrosome and that its deficiency induces a pathological continuum ranging from oligoasthenoteratozoospermia in heterozygotes to Azoospermia in homozygotes.

  • spink2 deficiency causes infertility by inducing sperm defects in heterozygotes and Azoospermia in homozygotes
    Embo Molecular Medicine, 2017
    Co-Authors: Zine-eddine Kherraf, Thomas Karaouzene, Guillaume Martinez, Emeline Lambert, Christelle Borel, Marie Christoukent, Amir Amiriyekta, Alexandra Vargas, Beatrice Dorphin
    Abstract:

    Azoospermia, characterized by the absence of spermatozoa in the ejaculate, is a common cause of male infertility with a poorly characterized etiology. Exome sequencing analysis of two azoospermic brothers allowed the identification of a homozygous splice mutation in SPINK2, encoding a serine protease inhibitor believed to target acrosin, the main sperm acrosomal protease. In accord with these findings, we observed that homozygous Spink2 KO male mice had Azoospermia. Moreover, despite normal fertility, heterozygous male mice had a high rate of morphologically abnormal spermatozoa and a reduced sperm motility. Further analysis demonstrated that in the absence of Spink2, protease-induced stress initiates Golgi fragmentation and prevents acrosome biogenesis leading to spermatid differentiation arrest. We also observed a deleterious effect of acrosin overexpression in HEK cells, effect that was alleviated by SPINK2 coexpression confirming its role as acrosin inhibitor. These results demonstrate that SPINK2 is necessary to neutralize proteases during their cellular transit toward the acrosome and that its deficiency induces a pathological continuum ranging from oligoasthenoteratozoospermia in heterozygotes to Azoospermia in homozygotes.

Heung Jae Park - One of the best experts on this subject based on the ideXlab platform.

  • what is the indication of varicocelectomy in men with nonobstructive Azoospermia
    Urology, 2007
    Co-Authors: Heung Jae Park
    Abstract:

    Objectives To investigate the effect of microsurgical varicocelectomy in nonobstructive azoospermic patients. The surgical outcomes were correlated with the histopathologic patterns of testicular specimens. Methods A total of 19 nonobstructive azoospermic men who underwent testicular biopsy and varicocelectomy were included in the study. In 15 patients, unilateral varicocelectomy was performed, and in 4, bilateral varicocelectomy was performed. An inguinal approach with a microsurgical technique was used. Postoperative semen analyses were performed in each patient 3 months after varicocelectomy. Results Testicular histologic examination revealed hypospermatogenesis in 3 patients, maturation arrest in 6, and germ cell aplasia in 10. After a mean follow-up of 7.4 months, motile sperm in the ejaculate was identified in 7 (36.4%) of the nonobstructive azoospermic patients. Of these 7 patients, 2 had hypospermatogenesis, 4 had maturation arrest, and 1 had Sertoli cell-only syndrome. All 7 patients had improvement in their sperm concentration and motility (0.36 × 10 6 /mL and 47.1%, respectively). However, 2 of these 7 patients with motile sperm after varicocelectomy had recurrence of the azoospermic state at their second postoperative semen analysis. Pregnancy was achieved by natural intercourse for 1 of the men (5.3%) with hypospermatogenesis. Conclusions Microsurgical varicocelectomy may offer patients with nonobstructive Azoospermia an opportunity to have sperm in their ejaculate and even the possibility of natural conception. Microsurgical varicocelectomy can be considered a viable option in selective patients with nonobstructive Azoospermia and varicocele, instead of the less cost effective and more bothersome assisted reproductive techniques.

Sherman J Silber - One of the best experts on this subject based on the ideXlab platform.

  • karyotyping of infertile males and their icsi offspring
    2018
    Co-Authors: Sherman J Silber
    Abstract:

    A massive summary of karyotyping results in newborn populations, reviewed by Van Assche, was published to determine to what extent chromosomal abnormalities could be responsible for the diagnosis of Azoospermia. It revealed an incidence of balanced translocations in a normal newborn population of 0.25%. A similar review of 7876 men with infertility undergoing karyotyping revealed an incidence of balanced translocations of 1.3%, more than four times that found in normal newborns [1–3]. When the analysis is restricted to men with oligospermia (i.e., less than 20 million per mL), some type of autosomal chromosome anomaly, either balanced Robertsonian translocations, balanced reciprocal translocations, balanced inversions, or extra markers, is found in 3% of patients. In azoospermic men, the incidence of such translocations was less than in patients with severe oligospermia but still greater than 1%. Sex chromosomal anomalies, such as Klinefelter’s syndrome, were found in more than 5% of azoospermic men and in 1.6% of oligospermic men. It is known that Klinefelter’s (XXY) occurs in 1/1000 (0.1%) of newborns. If 0.5% of men have Azoospermia, we would expect 5% of azoospermic men to have XXY Klinefelter’s.

  • chromosomal abnormalities in embryos derived from testicular sperm extraction
    Fertility and Sterility, 2003
    Co-Authors: Sherman J Silber, T Escudero, K Lenahan, Iman Abdelhadi, Zaid Kilani, Santiago Munne
    Abstract:

    Abstract Objective To compare the rate of chromosome abnormalities in embryos obtained from karyotypically normal patients with nonobstructive Azoospermia undergoing testicular sperm extraction (TESE) to those from patients undergoing intracytoplasmic sperm injection (ICSI) with ejaculated sperm. Design Retrospective analysis. Setting IVF centers. Patient(s) Male partners had either nonobstructive zoospermia or oligospermia. Intervention(s) Preimplantation genetic diagnosis. Chromosome enumeration was performed by fluorescence in situ hybridization (FISH). Embryos classified as abnormal were reanalyzed to study mosaicism. Main outcome measure(s) Chromosome abnormalities in embryos. Result(s) Embryos from ICSI cycles with ejaculated sperm (group 1) were 41.8% normal, 26.2% aneuploid, and 26.5% mosaic. In contrast, the embryos from ICSI cycles with TESE for nonobstructive Azoospermia (group 2) were 22% normal, 17% aneuploid, and 53% mosaic. The difference in mosaicism rate between the two groups of embryos was highly significant. Conclusion(s) The present study results indicate a high incidence of mosaicism in embryos derived from TESE in men with a severe deficit in spermatogenesis. Sperm derived from TESE for nonobstructive Azoospermia may have a higher rate of compromised or immature centrosome structures leading to mosaicism in the embryo.

  • normal pregnancies resulting from testicular sperm extraction and intracytoplasmic sperm injection for Azoospermia due to maturation arrest
    Fertility and Sterility, 1996
    Co-Authors: Sherman J Silber, Andre Van Steirteghem, Zsolt Nagy, Jiaen Liu, H Tournaye
    Abstract:

    Objective To see whether testicular sperm extraction could be used to perform intracytoplasmic sperm injection (ICSI) for men with nonobstructive Azoospermia caused by maturation arrest. Design Uncontrolled prospective trial of an attempt to find occasional elongated spermatids or spermatozoa in testes of azoospermic patients with maturation arrest and to use these haploid cells for ICSI. Setting European university-based center for reproductive medicine and private American community hospital. Patients Thirty-eight azoospermic males without obstruction and with biopsy-documented maturation arrest, seven of whom elected, with their wives, to undergo scrotal exploration and testicular sperm extraction with ICSI in an attempt to become pregnant. Interventions Histologic evaluation of spermatid development in 38 patients with azoospermic maturation arrest. Testicular sperm extraction with ICSI in seven random volunteers from this group. Main Outcome Measures Presence or absence of mature spermatids in the testis biopsy specimen of patients with azoospermic maturation arrest. Fertilization, cleavage, and pregnancy after testicular sperm extraction and ICSI in patients with azoospermic maturation arrest. Results All seven patients with azoospermic maturation arrest had occasional sperm found with testicular sperm extraction. Five had sufficient numbers (between 6 and 30) for ICSI, and those five had ETs. In four, the partners became pregnant. In all 38 patients examined, the maturation defect was in meiosis rather than in spermiogenesis. Conclusion Nonobstructive Azoospermia caused by maturation arrest may be treated with testicular sperm extraction with ICSI apparently as successfully as Sertoli cell only.

  • recent concepts in the management of infertility because of non obstructive Azoospermia
    Human Reproduction, 1995
    Co-Authors: Herman Tournaye, Sherman J Silber, Jiaen Liu, Michel Camus, Anita Goossens, P Nagy, A Van Steirteghem, Paul Devroey
    Abstract:

    Testicular biopsy has been widely used for the diagnosis of male infertility. Since the introduction of intracytoplasmic sperm injection (ICSI), spermatozoa recovered from a testicular biopsy specimen can be successfully used for establishing pregnancies. A few spermatozoa may be recovered from a wet preparation of a testicular biopsy, not only in obstructive azoospermic patients, but also in many patients with non-obstructive Azoospermia. In 36 out of 38 non-obstructive azoospermic patients sperm cells were recovered from a testicular biopsy specimen. However in two patients, spermatozoa could not be found after further preparation of the biopsy specimens for ICSI. In the remaining 32 patients, a normal fertilization rate of 56.8 % per succesfully injected oocyte was obtained after ICSI of testicular spermatozoa. In 84% of patients, embryos were replaced with an overall pregnancy rate of 28.9% per testicular biopsy or 34.3% per embryo transfer. The results clearly indicate that at present an excisional testicular biopsy should be offered to all azoospermic patient, irrespective of concentration of follicle stimulating hormone, testicular size or medical history.

E Becht - One of the best experts on this subject based on the ideXlab platform.

  • induction of spermatogenesis in men with Azoospermia or severe oligoteratoasthenospermia after antegrade internal spermatic vein sclerotherapy for the treatment of varicocele
    Asian Journal of Andrology, 2006
    Co-Authors: Vassilis Poulakis, Nikolaos Ferakis, Rachelle De Vries, U Witzsch, E Becht
    Abstract:

    Aim: To evaluate the treatment outcome of antegrade internal spermatic vein sclerotherapy in men with non-obstructive Azoospermia or severe oligoteratoasthenospermia (OTA) as a result of varicocele. Methods: Between September 1995 and January 2004, 47 patients (mean age 33.8 ± 6.3 years) underwent antegrade internal spermatic vein sclerotherapy for the treatment of varicocele with Azoospermia (14 patients) or severe OTA (33 patients). Testicular core biopsy was also performed in complete azoospermic patients who provided informed consent. The outcome was assessed in terms of improvement in semen parameters and conception rate. Results: Forty-two (89.4%) of 47 patients had bilateral varicocele. Serum follicle stimulating hormone (FSH) did not differ between patients with Azoospermia and severe OTA. After the follow-up of 24.8 ± 9.2 months, significant improvement was noted in mean sperm concentration, motility and morphology in 35 patients (74.5%). Comparison between groups during the follow-up revealed significantly higher values of sperm concentration, motility and normal morphology in the severe OTA group. Pregnancy was achieved in 14 cases (29.8%). Testicular histopathology of the azoospermic patients with postoperative induction of spermatogenesis revealed maturation arrest at spermatid stage, Sertoli-cell-only (SCO) with focal spermatogenesis or hypospermatogenesis. None of the patients with pure SCO pattern or maturation arrest at spermatocyte stage achieved spermatogenesis after the treatment. Preoperative serum FSH levels didn't relate to treatment outcome. Conclusion: Antegrade internal spermatic vein sclerotherapy is an easy and effective treatment for symptomatic varicocele. It can significantly reverse testicular dysfunction and improve spermatogenesis in men with severe OTA, as well as induce sperm production in men with Azoospermia, improving pregnancy rates in subfertile couples.