Science versus clinical adventurism in treatment of azoospermia

Multiple signaling pathways in Sertoli cells: recent findings in spermatogenesis

The functions of Sertoli cells in spermatogenesis have attracted much more attention recently. Normal spermatogenesis depends on Sertoli cells, mainly due to their influence on nutrient supply, maintenance of cell junctions, and support for germ cells' mitosis and meiosis. Accumulating evidence in the past decade has highlighted the dominant functions of the MAPK, AMPK, and TGF-β/Smad signaling pathways during spermatogenesis. Among these pathways, the MAPK signaling pathway regulates dynamics of tight junctions and adherens junctions, proliferation and meiosis of germ cells, proliferation and lactate production of Sertoli cells; the AMPK and the TGF-β/Smad signaling pathways both affect dynamics of tight junctions and adherens junctions, as well as the proliferation of Sertoli cells. The AMPK signaling pathway also regulates lactate supply. These signaling pathways combine to form a complex regulatory network for spermatogenesis. In testicular tumors or infertile patients, the activities of these signaling pathways in Sertoli cells are abnormal. Clarifying the mechanisms of signaling pathways in Sertoli cells on spermatogenesis provides new insights into the physiological functions of Sertoli cells in male reproduction, and also serves as a pre-requisite to identify potential therapeutic targets in abnormal spermatogenesis including testicular tumor and male infertility.

Potential consequences of clinical application of artificial gametes: a systematic review of stakeholder views

BACKGROUND

Recent progress in the formation of artificial gametes, i.e. gametes generated from progenitors or somatic cells, has led to scientific and societal discussion about their use in medically assisted reproduction. In animals, live births have already been achieved using artificial gametes of varying (cell type) sources and biological research seems to be progressing steadily toward clinical application in humans. Artificial gametes could potentially help not only infertile heterosexual couples of reproductive age of which one or both partners lacks functional gametes, but also post-menopausal women and same-sex couples, to conceive a child who will be genetically related to them. But as clinical application of these new technologies may have wider societal consequences, a proactive consideration of the possible impact seems timely and important. This review aims to contribute to this by providing a systematic overview of the potential consequences of clinical application of artificial gametes anticipated by different stakeholders.

METHODS

The electronic database 'Medline/Pubmed' was systematically searched with medical subject heading terms (MesH) for articles published in English between January 1970 and December 2013. Articles were selected based on eligibility and reference lists of eligible studies were hand searched. The reported potential consequences of clinical application of artificial gametes were extracted from the articles and were grouped into categories by content analysis. Per category, we noted which stakeholders referred to which potential consequences, based on author affiliations and, if applicable, study participants.

RESULTS

The systematic search yielded 2424 articles, and 84 studies were included after screening. Nine positive consequences, 21 specific consequences requiring consideration and 22 recommendations referring to clinical application of artificial gametes were documented. All positive consequences, consequences requiring consideration and recommendations could be categorized under the following eight objectives to be safeguarded during clinical application of artificial gametes: (i) timing the implementation of new treatments correctly, (ii) meeting 'plausible demands of patients', (iii) improving and safeguarding public health, (iv) promoting the progress of medical science in the interest of future patients, (v) providing treatments that are morally acceptable for the general public, (vi) controlling medical practice, (vii) offering treatments that allow acquisition of informed consent and (viii) funding treatments fairly. Professionals specialized in biomedical science, science journalists and professionals specialized in ethics all addressed these eight objectives on artificial gametes, whereas professionals specialized in law or political science addressed seven objectives. Although one study reported on the perspective of parents of under-aged patients on three objectives, the perspectives of patients themselves were not reported by the reviewed literature.

CONCLUSION

Of course, clinical introduction of artificial gametes should only be considered on the basis of reassuring outcomes of appropriate preclinical effectiveness and safety studies. In addition, potential users' views on the desirability and acceptability of artificial gametes should be studied before clinical introduction. A societal debate including all stakeholders is needed to determine the relative importance of all arguments in favor of and against the introduction of artificial gametes into clinical practice. More broadly, establishing pre-implementation processes for new medical techniques is relevant for all fields of medicine.

Congenital anomalies of the mesonephric duct and fertility

Agenesia of deferential duct and the others congenital malformations of mesonephronical duct are often encountering condition in andrological practice. This study presents the possibilities of reproductive medicine to restore the male fertility and concentrates on biological and clinical aspects of malformations of mesonephronic duct like factors for excretory male infertility. The investigations including 104 patients (mean age 30.25+/-1.91 years old) with congenital anomalies of mesonephronical duct with: Agenesia of mesonephronical derivates - case with unilateral agenesia of the deferent duct, kidney and left urether (n=1); Dysgenesia of the epididymis (n=5); Cysts of the epididymis (n=47); Agenesia of the deferential duct (n=48); Aplasia of the eja-culatorial duct (n=3). The following methods were used: open testicular biopsy by Vilar; objective findings in situ operation; bilateral epididymo - and deferentovesiculography; morphological specimens of the testicular and epididymal tissues; enzymohistochemical analysis of testicular specimens; the ejaculates and morphological analysis of spermatozoa were assessed for quality parameters by the standard protocol; enzymocytological research of spermatozoa in seminal fluid; biochemical analysis of seminal fluid fructose and citric acid concentrations; radioimmunoassay for measurements of blood FSH and testosterone concentration.

RESULTS

Most often observed localization of the malformations of mesonephronic canal is bilateral at 54.81%. The testicular specimens proved preserved testicular architecture and spermatogenesis, and the epididymal slides showed dilatation of the epididymal tubules, which were overfilled with a lot of spermatozoa. The strongest expression of the enzymichistochemical NADH-TR reactions is in the Sertoli cells. We observed spermatozoa with disrup-ted configuration among which the abnormalities in sperm head and acrosome were predominated. The biochemical analysis of seminal fluid proves normal citric acid and low or lack of fructose concentration in seminal fluid. There were no breaches in endocrine regulation of the reproductive process. Patients with congenital anomalies of mesonephronic canal have preserving fertility in 31.73%. There are morpho-functional disorders of the testes, epididymis and seminal ducts in 68.27%.

CONCLUSION

There are normal spermatogenesis but definite sterility. These results necessitate an application of plastic reconstructive operation for recovery of fertilizing ability of the patients, or their involvement in ICSI programme.

Developmental potential of elongating and elongated spermatids obtained after in-vitro maturation of isolated round spermatids

BACKGROUND

Round spermatid injections are associated with disappointing clinical outcomes, and although these cells have been shown to mature into late spermatids in vitro, the developmental potential of such gametes remains to be demonstrated.

METHODS

Round spermatids were isolated from 12 testicle samples of patients with obstructive azoospermia, hypoplasia, complete maturation arrest, and incomplete Sertoli cell-only syndrome. They were cultured for 7 days at 32 degrees C, 5% CO(2)in air, in microdrops of Vero cell-conditioned medium containing 10% synthetic serum substitute.

RESULTS

From the 238 round spermatids cultured, 25.2% attained the elongating and 5.5% the elongated spermatid stage (3-4 days per step). Relatively higher maturation rates were found in cases with obstructive azoospermia, but differences were significant only for elongated spermatids (9.3%). No differences were found in maturation rates between cases with non-obstructive azoospermia (4.3% of elongated spermatids). Experimental microinjections with elongating and elongated spermatids revealed a low fertilization rate (40.9%) but a normal blastocyst formation rate (60%).

CONCLUSIONS

Late spermatids resulting from in-vitro culture of round spermatids in conditioned medium, either in controls in cases with a spermiogenetic block, appeared able to successfully fertilize the human oocyte and elicit normal embryo development.