On the descent of the epididymo-testicular unit, cryptorchidism, and prevention of infertility

Résumé Cette revue complète traite en profondeur les progrès réalisés dans la compréhension des mécanismes moléculaires à la base de la cryptorchidie, une pathologie fréquente décrite pour la première fois aux environs de 1786 par John Hunter. La première partie est. centrée sur la physiologie, l’embryologie et l’histologie de la descente épididymo-testiculaire. Durant les 20 dernières années, la descente épididymo-testiculaire est. devenue la victime de dessins schématiques associés à un rejet injustifié de données histologiques valides. Cette partie discute aussi les rôles qu’ont dans la descente épididymo-testiculaire l’hormone libérant les gonadotrophines, les facteurs de croissance fibroblastiques, l’hormone antimüllérienne, les androgènes, l’inhibine B, et l’insuline-like 3. La seconde partie aborde l’étiologie et l’histologie, ainsi que l’importance de la minipuberté pour un développement normal de la fertilité. Un regard critique est. porté sur les recommandations cliniques actuelles qui conseillent la seule orchidopexie précoce comme le meilleur traitement possible. Finalement, en combinant les informations issues de la physiologie classique et la production des données génomiques les plus en pointe dans un tableau complet, l’importance du traitement hormonal dans la prévention de l’infertilité induite par la cryptorchidie est soulignée

Insulin 3-like hormone and its role in epididymo-testicular descent

PURPOSE: The role of insulin 3-like (Insl3) hormone signaling in the testicular descent process has been demonstrated. The purpose of the present study was to evaluate epididymal development in Insl3-deficient mice. MATERIALS AND METHODS: Heterozygous and homozygous Insl3 mutants of a mixed CD1 X 129/Sv genetic background were generated by breeding Insl3-/- females with Insl3+/- males, and their genotypes were determined by polymerase chain reaction. On the first postnatal day, newborn males were sacrificed, embedded in paraffin, and cut in 4 µm sections. Sections were stained with hematoxylin/eosin and immunoreacted with anti-± actin antibody. RESULTS: An analysis of stained sections indicated an arrest in the development of the epididymis in all homozygous mice. The cauda and corpus of the epididymis were undersized. Compared to the heterozygous epididymis, the homozygous epididymis had fewer peritubular layers and dwarfish musculature. We confirmed this with immunostaining with monoclonal antibodies against ± -smooth muscle actin. CONCLUSION: Defective development of the smooth musculature in the epididymis of Insl3 homozygous mutant mice, combined with its high intraabdominal undescended position, supports previous observations regarding the importance of intact epididymis morphology and function for descent of the epididymo-testicular unit

Decreased expression of FGFR1, SOS1, RAF1 genes in cryptorchidism

In recent years, several genes were found to be involved in the process of epididymo-testicular descent, the most frequently cited ones include INSL3, HOXA10, GNRHR, and KAL1. In this study, we analyzed the differences in gene expression profiles between cryptorchid and descended testes. In particular, we analyzed expression of all recently published genes known to be associated with undescended testis

Early successful orchidopexy does not prevent from developing azoospermia

INTRODUCTION: The incidence of Ad spermatogonia (stem cells for fertility) was assessed in 20 cryptorchid patients, all of whom had a successful orchidopexy in childhood but developed azoospermia following puberty. MATERIALS AND METHODS: From a cohort of 231 patients who had a semen analysis following successful orchidopexy 20 patients (9%) had azoospermia. The patients were classified into 2 groups according to the time of surgery: A = < 21 months of age (n = 5, mean = 10.7 &plusmn; 8.6 months) and B = during childhood (n = 15, mean = 10.1 &plusmn; 3 years). Nine of the 20 patients (45%) had bilateral cryptorchidism: A = 1 and B = 8. Testicular biopsies were performed during orchidopexy and analyzed with semi-thin technique. The number of Ad spermatogonia and entire number of germ cells was determined. The patients' semen analyses were evaluated at least twice; FSH and testosterone plasma values were estimated. RESULTS: In group A, all patients had germ cells at the time of surgery (mean = 1.04 &plusmn; 1.4 germ cells per tubular cross section); only 6 patients in group B (40%) had no germ cells (mean = 0.17 &plusmn; 0.4); A vs. B, p = 0.0133. Importantly, Ad spermatogonia were absent in the entire study population. The plasma FSH of 16 patients (80%) was abnormal [median = 16.35 IU/L (Interquartile range of sample - IQR 9.075-27.85 95% CI, 3-53)] while the plasma testosterone of all the patients was normal. CONCLUSIONS: The most severe cause of infertility in cryptorchid patients cannot be mitigated by an early successful surgery alone

Testicular gene expression in cryptorchid boys at risk of azoospermia

Despite timely and successful surgery, 32% of patients with bilateral and 10% with unilateral cryptorchidism will develop azoospermia. Cryptorchid boys at risk of azoospermia display a typical testicular histology of impaired mini-puberty at the time of the orchidopexy. During mini-puberty increased gonadotropin and testosterone secretion stimulate transformation of gonocytes into Ad spermatogonia. In azoospermia risk group this transformation is to a great extent impaired. This study aimed to analyze data on whole genome expression signatures of undescended testes at risk of developing azoospermia. Twenty-three testicular biopsies from 22 boys were analyzed (19 testes from 18 boys with cryptorchidism) and 4 contralateral descended testes from patients with testicular agenesis. Expression profiling identified 483 genes not or under-expressed in the azoospermia risk group compared with the control and LAZR groups. Annotated loci were associated with spermatogenesis. Other significant genes were cellular defense response genes and hormone controlled loci involved in spermatogenesis. Some genes transcribed in normal adult meiotic and post-meiotic germ cells are activated in healthy juvenile Ad spermatogonia. Thus, molecular events initiating the testicular expression program at the onset of puberty and maintaining it during adulthood occur very early in prepubertal testes. This molecular event is to a great extent impaired in HAZR group lacking Ad spermatogonia (stem cells for spermatozoa) indicating impaired mini puberty

Intestinal biopsy is not always required to diagnose celiac disease: a retrospective analysis of combined antibody tests

Abstract Background The objective of this study was to compare celiac disease (CD)– specific antibody tests to determine if they could replace jejunal biopsy in patients with a high pretest probability of CD. Methods This retrospective study included sera from 149 CD patients and 119 controls, all with intestinal biopsy. All samples were analyzed for IgA and IgG antibodies against native gliadin (ngli) and deamidated gliadin peptides (dpgli), as well as for IgA antibodies against tissue transglutaminase and endomysium. Results Tests for dpgli were superior to ngli for IgG antibody determination: 68% vs. 92% specificity and 79% vs. 85% sensitivity for ngli and dpgli, respectively. Positive (76% vs. 93%) and negative (72% vs. 83%) predictive values were also higher for dpgli than for ngli. Regarding IgA gliadin antibody determination, sensitivity improved from 61% to 78% with dpgli, while specificity and positive predictive value remained at 97% (P Conclusion Antibody tests for dpgli yielded superior results compared with ngli. A combination of three or four antibody tests including IgA anti-tissue transglutaminase and/or IgA anti- endomysium permitted diagnosis or exclusion of CD without intestinal biopsy in a high proportion of patients (78%). Jejunal biopsy would be necessary in patients with discordant antibody results (22%). With this two-step procedure, only patients with no CD-specific antibodies would be missed.</p

Gubernaculum, antsėklidžio ir sėklidės nusileidimas: literatūros apžvalga

Cryptorchidism is a common disorder in boys that has been widely studied both experimentally and clinically. The role of the gubernaculum, a mesenchymal tissue extending from the fetal testis and epididymis to the developing scrotum, is still unclear. Even the name is debated: ‘gubernaculum epididymis’ or ‘gubernaculum testis’. This review does not aim to provide a global overview of competing theories on testicular descent, but focuses on the role of the gubernaculum in epididymo-testicular descent. We identified four major pitfalls of gubernaculum research: the role of the gubernaculum, of insulin-like peptide 3, anti-Müllerian hormone, and androgens. The major critical issues were that the gubernaculum plays a guiding role for the epididymis, descending prior to the testis and expanding the inguinal canal; insulin-like peptide 3 is not as important for the process of descent in humans as the rate of insulin-like peptide 3 mutations is low; anti-Müllerian hormone plays no significant role in epididymo-testicular descent; androgens and gonadotropins play a crucial role in epididymo-testicular descent. The role of the epididymis in the complex process of gubernaculum, epididymis, and testis migration is underestimated and should be included in future research