Intra-abdominal Cryptorchidism Research Articles

Laparoscopic Orchidopexy after 4 Weeks of Testicular Traction with Preservation of Blood Supply: A New Concept for the Treatment of Intra-Abdominal Cryptorchidism: Original Article

Laparoscopic Orchidopexy after 4 Weeks of Testicular Traction with Preservation of Blood Supply: A New Concept for the Treatment of Intra-Abdominal Cryptorchidism: Original Article

Abdominal Cryptorchidism with Complete Dissociation between the Testis and Deferent Duct Mimicking Testicular Regression Syndrome

Complete separation of the deferent duct from the epididymis in cryptorchid testes residing in the abdomen is an extremely rare variant of developmental disorders of the testis and epididymis. Available sources mention only three clinical cases similar to our observations. The unique anatomic aspects of this disorder hamper the correct diagnosis of an intra-abdominal cryptorchid testis. Two boys with nonpalpable left-sided cryptorchidism underwent diagnostic laparoscopy, revealing an intra-abdominally located testis. The epididymis was completely separated from the deferent duct, and the epididymis and testis were supplied by testicular vessels. Exploration of the inguinal canal revealed blind-ending deferent ducts. The testis was brought down through the inguinal canal and fixed in the scrotum in both boys. The follow-up examination at 6 months revealed no signs of testicular atrophy or malposition of the testis in either patient. With our observations in mind, the exclusive use of a transscrotal or transinguinal approach as the initial surgical exploration in the treatment of patients with nonpalpable forms of cryptorchidism may be inappropriate. Careful laparoscopic examination of the abdominal cavity is indispensable in children with suspected testicular regression syndrome or nonpalpable forms of cryptorchidism.

Usefulness of computed tomography for cryptorchidism in bulls.

Cryptorchidism is defined as the failure of the testis to descend into the scrotal position. Bulls with cryptorchidism have problems in both meat quality and husbandry management; thus, it is greatly important to accurately identify the retained testis and remove it during the early stage. Abdominal computed tomography (CT) was performed under general anesthesia in 34 bulls aged 3-9 months with cryptorchidism. All bulls underwent laparoscopic or incision approach for cryptorchidectomy, and 40 testes were dissected. The detection rates of retained testes were 64.5% in the abdominal cavity and 100% in the subcutaneous inguinal region, and the total detection rate was 72.5%. Furthermore, all cases in this study were suspected to have intra-abdominal cryptorchidism in primary care, but CT revealed that 22.5% of cases had cryptorchidism in the subcutaneous inguinal region. The CT value (mean ± standard deviation) of the retained testes was 20.96 ± 7.54 Hounsfield Unit, and the CT value and size of the retained testes showed a positive weak correlation with bovine age. Therefore, there is the demerit that general anesthesia and a huge device are necessary; nevertheless, CT is suggested to be useful in identifying the location of retained testes and selecting an appropriate surgical approach in bulls with cryptorchidism. Moreover, CT findings suggested that the maturation of the retained testes might depend not on the descending process but on age.

Evaluation of Fowler-Stephens orchiopexy for high-level intra-abdominal cryptorchidism: a systematic review and meta-analysis

Evaluation of Fowler-Stephens orchiopexy for high-level intra-abdominal cryptorchidism: a systematic review and meta-analysis

FEAT enhances INSL3 expression in testicular Leydig cells.

FEAT, the protein encoded by methyltransferase-like 13 (METTL13), is aberrantly upregulated in most human cancers and potently drives tumorigenesis in vivo; however, its role in normal tissues remains elusive. Immunoblotting has displayed weak FEAT expression in normal human tissues, including the testis. Here, we found that FEAT is expressed in fetal and adult Leydig cells in the testis. FEAT knockdown using siRNA increased primary cilia formation in MA-10 Leydig tumor cells, accompanied by enhanced 5' adenosine monophosphate-activated protein kinase (AMPK) activation. Immunofluorescence analyses of FEAT-silenced MA-10 cells showed diminished insulin-like factor 3 (INSL3) expression. A male Mettl13+/- mouse developed bilateral intraabdominal cryptorchidism, suggesting defective INSL3 production by fetal Leydig cells. Leydig cells from the mouse showed markedly decreased INSL3 protein by immunohistochemistry. Together, these results suggest that FEAT facilitates the INSL3 production in testicular Leydig cells that is essential for transabdominal testis migration.

Polymorphism of exon 13 lgr8 gene as risk factors for cryptorchidism in children

Cryptorchidism refers to incomplete descend of the testes into the scrotum with the testes located in the normal tracts. The incident is 3-5% among infants born at term. The complications are infertility and testicular cancer. Cryptorchidism has a multifactorial aetiology and the role of exon 13 lgr8 gene polymorphism remains unclear. This study aims to find the frequency polymorphism of exon 13 lgr8 gene in children with cryptorchidism and to prove as a risk factor for cryptorchidism. This study is an observational case control study, conducted at the children’s in two general hospital and one maternity clinic from September 2010 until March 2011, with 31 children cryptorchidism as cases and 31 healthy children as controls who were matched by gestational age and age of the child. Polymorphism of exon 13 lgr8 gene was evaluated by sequencing of PCR results at YAYASAN GENEKA Eijkman Molecular Biology Institution Jakarta. Frequency was analyzed by percentage, polymorphism was analyzed by paired odds ratio and analyzed by computerized programmes, hypothesis with a confidence interval (a) was accepted if p<0,05. This study found a percentage of intraabdominal cryptorchidism of 41,94%, inguinal cryptorchidism of 41,94%, and prescrotal cryptorchidism of 16,12%. This study also found a frequency polymorphismof exon13 lgr8 gene (S337A = 54,84%; P340P = 41,94%; H345P = 61,29%; K346K = 90,32%; Q354K = 16,13%; Q356P = 29,03%; S357S = 48,39%). Polymorphisms S337A (TCA→ GCA) p = <0,001; H345P (CAC → CCC) p = 0,03; Q356P (CAG → CCG) p = 0,004; and S357S (TCT → TCC) p = <0,001 of exon 13 lgr8 gene were found significantly more often in cases. In summary polymorphism S357S is associated with a new marker; polymorphisms S337A; Q356P are associated with an increased risk; polymorphism H345P is associated with an increased risk or new marker of cryptorchidism in boys. This study is expected to be used in the determination of therapeutic decisions, as a guide for prognosis and as a foundation for further studies.

Splenogonadal fusion: Report of four cases and review of the literature

Splenogonadal fusion (SGF) is a rare congenital abnormality that affects children of both genders. Very few cases of SGF have been diagnosed preoperatively. In this study, the surgical findings and laparoscopic treatment of four children with SGF associated with intra-abdominal cryptorchidism are described. Laparoscopy was demonstrated to be the only accurate exploratory procedure for the diagnosis and surgical treatment of SGF with non-palpable testis.

Insulin-Like 3 Signaling Is Important for Testicular Descent but Dispensable for Spermatogenesis and Germ Cell Survival in Adult Mice1

Relaxin family peptide receptor 2 (RXFP2) is the cognate receptor of a peptide hormone insulin-like 3 (INSL3). INSL3 is expressed at high levels in both fetal and adult Leydig cells. Deletion of Insl3 or Rxfp2 genes in mice caused cryptorchidism resulting from a failure of gubernaculum development. Using a novel mouse transgenic line with a knock-in LacZ reporter in the Rxfp2 locus, we detected a robust Rxfp2 expression in embryonic and early postnatal gubernaculum in males and in postmeiotic spermatogenic cells in adult testis. To study the role of INSL3/RXFP2 signaling in male reproduction, we produced a floxed Rxfp2 allele and used the Cre/loxP approach to delete Rxfp2 in different tissues. Using Cre transgene driven by retinoic acid receptor beta promoter, conditional gene targeting in gubernacular mesenchymal cells at early embryonic stages caused high intraabdominal cryptorchidism as in males with a global deletion of Rxfp2. However, when the Rxfp2 was deleted in gubernacular smooth or striated muscle cells, no abnormalities of testicular descent or testis development were found. Specific ablation of Rxfp2 in male germ cells using Stra8-icre transgene did not affect testis descent, spermatogenesis, or fertility in adult males. No significant change in germ cell apoptosis was detected in mutant males. In summary, our data indicate that the INSL3/RXFP2 signaling is important for testicular descent but dispensable for spermatogenesis and fertility in adult males.

Seminoma Arising from Intra-abdominal Cryptorchidism with Ipsilateral Renal Agenesis: A Rare Association.

Unilateral renal agenesis is usually asymptomatic and may be found incidentally during examination for other causes. The incidence of testicular tumors arising from cryptorchidism is well established, but if it is coexistent with ipsilateral renal agenesis, the diagnosis and management becomes a challenge. Only three cases of such association have been reported in literature so far. This association has to be kept in mind when dealing with a case of testicular tumor arising from abdominal cryptorchidism, so that the function of the other kidney can be assessed before surgery, and protection given to it in the event of using radiotherapy in an adjuvant setting.

Laparoscopic Testicular Preservation in Adults with Intra-Abdominal Cryptorchidism: Is It Beneficial?

Purpose. To present the results in a midterm followup of laparoscopic testicular preservation in adults with intra-abdominal cryptorchidism. Methods. We analyzed 14 adult patients with cryptorchidism (19 testes) submitted to transabdominal laparoscopic evaluation and treatment of the condition. Data was collected retrospectively from a prospective database from August 2005 to May 2010. It analyzed patient age, affected side, procedure, mean operative time, mean hospital stay, postoperative testis position, intra- and postoperative complications, presence of malignancy in the removed testis, and midterm outcomes: size of the testis, development of tumors, and fertility. Results. Mean patient age was 29 (18–54) years. Thirteen (68.4%) testes were preserved. There were no intra- or postoperative complications. After a mean followup of 48.7 (20–64) months, all patients submitted to orchiopexy had the organs correctly positioned, although 2 testes were significantly smaller than before the procedure. No patient presented any signs of malignancy during the followup. Fertility was not preserved in bilateral cases. Conclusion. Laparoscopic testicular evaluation and eventual preservation are feasible and safe. In a midterm followup, testicular tumor is not a concern, and unfortunately, fertility may not be preserved in bilateral cases.

2020 INSL3 RECEPTOR RXFP2 IS EXPRESSED ON THE SPERM ACROSOME

You have accessJournal of UrologyInfertility: Physiology, Pathophysiology, Basic Research1 Apr 20112020 INSL3 RECEPTOR RXFP2 IS EXPRESSED ON THE SPERM ACROSOME Daniel DaJusta, Candace F. Granberg, Yi Wang, Shaohua Zhang, Kent Hamra, and Linda A. Baker Daniel DaJustaDaniel DaJusta Dallas, TX More articles by this author , Candace F. GranbergCandace F. Granberg Dallas, TX More articles by this author , Yi WangYi Wang Dallas, TX More articles by this author , Shaohua ZhangShaohua Zhang Dallas, TX More articles by this author , Kent HamraKent Hamra Dallas, TX More articles by this author , and Linda A. BakerLinda A. Baker Dallas, TX More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2248AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Insulin-3 (INSL3) and its receptor, RXFP2 (aka LGR8), are key mediators in testicular descent due to their action on the fetal gubernaculum. Insl3 or Rxfp2 knockout mice demonstrate bilateral intra-abdominal cryptorchidism and infertility. The RXFP2 receptor mRNA has been demonstrated in pachytene spermatocytes, but the function and localization of the protein in spermatogenesis has not been further documented. We sought to investigate whether adult sperm express the RXFP2 receptor. METHODS Sperm were extracted from the cauda epididymis of reproductive age WT mice and from human ejaculated sperm. Sperm in standard medium was capacitated with calcium and sodium bicarbonate for 1 hour. To assess permeabilized (fixed) sperm, capacitated sperm were air dried on slides for 20 minutes, fixed in 4% paraformaledhyde and washed in PBS. Anti-RXFP2 rabbit polyclonal antibody 1:150 was incubated followed by red fluorescent anti-rabbit donkey antibody 1:1000. Green fluorescent acrosome staining was performed with FITC labeled Anti-Peanut Agglutinin antibody (PNA-FITC) followed by DAPI blue nuclear counterstaining. To assess non-permeabilized (live) sperm, capacitated sperm were centrifuged and resuspended in PBS with anti-RXFP2 rabbit polyclonal antibody 1:150. Again, sperm were centrifuged and resuspended in PBS with anti-rabbit donkey antibody 1:1000. PNA-FITC was then added for acrosome staining. Finally, 50μl of the sperm solution was slide mounted with DAPI counterstain. Control experiments omitted the primary antibody. Images were acquired with a Nikon Eclipse fluorescent microscope using NIS-Elements Br 2.30 software. RESULTS The acrosomes of capacitated adult WT mice sperm and human ejaculated sperm in both permeabilized and non-permeabilized state stained positive for RXFP2 (Figure 1). CONCLUSIONS The RXFP2 protein is localized to the acrosome of mature spermatozoa in mice and human. Given this observation, we speculate a possible new role for the INSL3-RXFP2 signaling system in acrosomal functions. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e807-e808 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Daniel DaJusta Dallas, TX More articles by this author Candace F. Granberg Dallas, TX More articles by this author Yi Wang Dallas, TX More articles by this author Shaohua Zhang Dallas, TX More articles by this author Kent Hamra Dallas, TX More articles by this author Linda A. Baker Dallas, TX More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

The development and anatomy of the gubernaculum in Hoxa11 knockout mice

Background The gubernaculum is central to testicular descent, with recent evidence suggesting that it elongates to the scrotum like a limb bud. Homeobox (Hox) genes involved in limb bud outgrowth are expressed within the gubernaculum. Mice with homozygous Hoxa11 gene deletions have bilateral cryptorchidism. This study investigated the precise anatomical effects of Hoxa11 mutation on the mouse gubernaculum. Methods The pelvises of postnatal mice (n = 46; days 1-10) with Hoxa11 knockout (n = 19), heterozygotes (n = 11), and wild-type (n = 16) mice were serially sectioned and stained with hematoxylin and eosin. Immunohistochemistry was performed for the presence of desmin. Results Hoxa11 mutant mice had intraabdominal cryptorchid testes and highly convoluted vas deferentia. The gubernacular bulbs were abnormal, with no “outgrowth” and persistence of the prenatal “swelling reaction.” Desmin immunostaining revealed the lack of undifferentiated mesenchymal cells usually seen as a “swirl” within the bulb and decreased formation of cremaster muscle. Conclusions Hoxa11 may be involved in forming the growth center seen as the “swirl” of mesenchyme within the gubernacular bulb, consistent with these cells being required for gubernacular elongation during testicular descent. Hoxa11 mutations may well contribute to failure of gubernacular migration in boys with cryptorchidism.

Bilateral abdominal cryptorchidism with large left testicular seminoma and failed right urogenital union

This is a case report of a 32-year-old male with bilateral intra-abdominal cryptorchidism. A large seminoma had developed on the left testis with paraaortic lymph nodes metastasis. The tumour was excised easily. The right testis was found just inside the deep inguinal ring, without the vas deferens in the spermatic cord. The patient requested orchidopexy despite the well-explained risk of cancer development. Therefore, a second right groin incision was performed. In the right inguinal canal, there was a normal-looking vas deferens that ended in an atrophic nubbin of fibrous tissue without an epididymis. This is the sixth case in the literature of failed urogenital union resulting in complete separation of testis and vas deferens. The patient underwent orchidopexy and had four cycles of chemotherapy, which led to complete remission of the metastasis. This case highlights the fact that an impalpable undescended testis and finding of blind-end vas deferentia are not enough to establish the diagnosis of vanished testis. The decision to undergo orchiectomy in cases of bilateral cryptorchidism after puberty is also discussed. In our opinion, the choice should be made by the patient after a discussion of the risk for cancer development in the salvaged testis.

Loss of Insl3: A Potential Predisposing Factor for Testicular Torsion

The testicular hormone Insl3 is critical for mouse gubernacular development. Knockout mice exhibit bilateral intra-abdominal cryptorchidism with absent gubernaculum. Prior studies described torsion of the vas deferens in Insl3 mutant mice. We performed a detailed anatomical analysis of the vas deferens and testis in Insl3 mutant mice to characterize associated anomalies further. Insl3 wild-type (Insl3(+/+)), heterozygous (Insl3(+/-)) and knockout (Insl3(-/-)) male mice were examined either prepubertally (postnatal day 23) or in adulthood (postnatal day 90 or later). The macroscopic appearance, characteristics, and mobility of the testes and spermatic cord were recorded. We examined 56 prepubertal and 33 adult mice (175 testes, 28 [20:8] Insl3(+/+), 97 [60:37] Insl3(+/-), 50 [32:18] Insl3(-/-)). Unlike normal Insl3(+/+) testes, 94% of Insl3(-/-) testes were located intra-abdominally at all ages. Delayed descent occurred in Insl3((+/-)) testes, since 37% of postnatal day 23 and 8% of P90 or later testes were intra-abdominal. Vas elongation/convolution and spermatic cord twisting were noted in 65% of Insl3(-/-), 27% of Insl3((+/-)) and 0% of Insl3(+/+) testes. While all Insl3(+/+) testes were normal, 5% of Insl3((+/-)) and 32% of Insl3(-/-) testes showed significant testicular pathology, including torsion, atrophy and vanished testis, which statistically increased with age. Poorly formed gubernacula and increased testicular mobility in Insl3 mutant mice result in spermatic cord anomalies, delayed/absent testicular descent and subsequent testicular torsion in a gene dose dependent manner. Prepubertal testicular torsion in the mutant mice predisposes to testicular atrophy and vanishing testes in adulthood. Thus, Insl3 is a candidate signaling molecule in human delayed testicular descent and torsion.

The effect of diethylstilbestrol on inducing abdominal cryptorchidism and relevant genetic expression in rats

To study the effect of diethylstilbestrol (DES) at different doses on transabdominal testicular descent in rats and the expression of INSL3 in the testis and HOXA10 in the gubernaculum. Fifty E13.5 (embryonic day 13.5) pregnant female SD rats were randomly divided into five groups that received a subcutaneous injection of DMSO, 2.5, 5.0, 10.0 and 20.0 mg/kg DES (group A, B, C, D and E), respectively. Male offspring were killed at E19.5, and then fetal mortality, the degree of transabdominal testicular ascent (DTA) was determined by a stereomicroscope. The mRNA expressions of INSL3 in the testis and HOXA10 in the gubernaculum were determined by RT-PCR. The expression of INSL3 protein was determined by Western blotting. Male fetal mortality in group A, B, C, D, and E were 3.57%, 6.90%, 12.00%, 19.23% and 36.36%, respectively, which showed a dose-effect relationship between DES and the male fatal mortality (r=0.999, P<0.01). DTA in group B, C, D and E were (23.7+/-1.7) U, (38.8+/-1.9) U, (49.3+/-1.8) U and (58.6+/-2.1) U that were significantly larger than that in group A [(8.5+/-1.3) U] (q=46.12, 88.53, 120.44 and 141.37, respectively, P<0.01). There was also a dose-effect relationship between DES and DTA. In group B, C, D, and E, the expression of INSL3 mRNA were 0.9570+/-0.1490, 0.6760+/-0.1380, 0.0170+/-0.0040 and 0.0013+/-0.0003, respectively; the expressions of INSL3 protein were 0.8360+/-0.1520, 0.5310+/-0.1070, 0.0140+/-0.0020 and 0.0011+/-0.0003, respectively, which were significantly larger than the expression of INSL3 mRNA (1.801+/-0.126) and INSL3 protein (1.612+/-0.134) in group A (qmRNA=40.4840, 52.4402, 83.1585 and 82.0582, respectively, and qprotein=38.6151, 52.2747, 77.2756 and 76.1983, respectively, P<0.01). The expression of HOXA10 mRNA in group A, B, C, D, and E were 0.945+/-0.125, 0.940+/-0.119, 0.656+/-0.115, 0.544+/-0.118 and 0.463+/-0.114, respectively. Compared with the expression of HOXA10 mRNA in group A, the expression of group B was not significantly different (q=0.2213, P>0.05), those in other groups were down-regulated significantly (q=12.4304, 17.2477 and 20.2789, respectively, P<0.01). DES inhibited transabdominal testicular descent dose-dependently via down-regulating the expression of INSL3. HOXA10 may play no role in low-dosage DES induced intra-abdominal cryptorchidism, but down-regulated HOXA10 mRNA was involved in high-dosage DES induced ones.

INSL3/RXFP2 Signaling in Testicular Descent

Mutations of the insulin-like peptide 3 (INSL3) hormone or its receptor, RXFP2, cause intraabdominal cryptorchidism in male mice. Specific RXFP2 expression in mouse gubernacula was detected at embryonic day 14.5 and markedly increased after birth in the developing cremaster muscle, as well as in the epididymis and testicular Leydig and germ cells. INSL3 treatment stimulated cell proliferation of embryonic gubernacular and Leydig cells, implicating active INSL3-mediated signaling. The transcription factor SOX9, a known male sex determination factor, upregulated the activity of the RXFP2 promoter. INSL3 is sufficient to direct the first transabdominal phase of testicular descent in the absence of hypothalamic-pituitary-gonadal axis signaling or Hoxa10, although these factors are important for inguinoscrotal testicular descent. Similarly, conditional ablation of the androgen receptor gene in gubernacular cells resulted in disruption of inguinoscrotal descent. We performed mutation screening of INSL3 and RXFP2 in human patients with cryptorchidism and control subjects from different populations in Europe and the USA. Several missense mutations were described in both the INSL3 and RXFP2 genes. A novel V39G INSL3 mutation in a patient with cryptorchidism was identified; however, the functional analysis of the mutant peptide did not reveal compromised function. In more than 2000 patients and controls analyzed to date, the T222P RXFP2 mutation is the only one strongly associated with the mutant phenotype. The T222P mutant receptor, when transfected into 293T cells, had severely decreased cell membrane expression, providing the basis for the functional deficiency of this mutation.

A Case Report: An Adult With Omental Incarceration of a Testicle, an Unexpected Finding at Herniorraphy

Inguinal herniorraphy is the most common surgical procedure in the United States. Intra-abdominal testicles and cryptorchidism can be seen in children with widely patent processus vaginalis. Testicular torsion is a surgical emergency that can be corrected without sacrificing the testicle if treated early and appropriately. No previous case has been reported with an adult's testicle having become incarcerated in the omentum contained within an indirect inguinal hernia sac simulating a possible testicular torsion.

Effects of laparoscopic division of spermatic vessels on histological changes of testes: long-term observation in the model of prepubertal rat

Laparoscopic Fowler-Stephens and Palomo procedures are now commonly performed in children with high positioned intra-abdominal cryptorchidism and varicocele, respectively. During the procedures, the spermatic vessels are ligated and therefore the question of risk related to testicular atrophy is often raised. The long-term follow-up of the histology after the procedures is rare. In this study, we simulated a laparoscopic spermatic vessels clipping and division (SVCD) in a prepubertal rat model, and examined the histological alterations of the testes with regard to spermatogenic arrest between prepuberty and middle age. Thirty-day-old Wistar rats divided randomly into three groups underwent laparoscopic sham operation, unilateral SVCD and unilateral SVCD with additional contralateral orchiectomy, respectively. Histological investigations observed on semithin and paraffin sections were performed at seven different postoperative intervals between day 9 and day 540. We defined partial, most and complete spermatogenic arrest of the seminiferous tubules to correspond with mild, severe spermatogenic arrest and atrophy, respectively. Laparoscopic SVCD induced testicular spermatogenic arrest in a total of 85% of the operated testes with different severity; 27% of operated testes with mild or severe spermatogenic arrest were seen between puberty and middle age (day 45-540 postoperative), and their size was only slightly reduced. Of the operated testes, 51% showed atrophic signs with a striking decrease in size, and their contralateral testes revealed in all cases mild or severe spermatogenic arrest started as early as day 45 postoperatively. Parallel to the spermatogenic arrest, Leydig cell hyperplasia developed frequently in impaired testes, especially in those without contralateral testes, finally reaching a typical adenoma size. Laparoscopic SVCD in prepubertal rats could disturb spermatogenesis with differing severity in most cases. This impairment could persist from peripuberty to middle age, and even involve the contralateral testes, in the case of operated testes and show complete spermatogenic arrest. This study showed that laparoscopic SVCD may have high risk in compromising the operated testis.

Over Expression of Insulin-Like 3 Does Not Prevent Cryptorchidism in GNRHR or HOXA10 Deficient Mice

Insulin-like 3 hormone is critical for the induction of growth and differentiation of gubernacular ligaments during embryonic testicular descent. Mice with mutation of insulin-like 3 or its receptor show high intra-abdominal cryptorchidism. We tested whether transgenic over expression of Insl3 can reverse inguinoscrotal cryptorchidism in mice deficient in Gnrhr or Hoxa10 genes. Hoxa10 and Gnrhr deficient mice were intercrossed with Insl3 transgenic mice. The phenotype of the mutant mice and expression of the genes involved in testicular descent were analyzed. Using quantitative reverse transcriptase-polymerase chain reaction we evaluated expression of the genes in neonatal gubernacular cells on INSL3 (Phoenix Pharmaceuticals, Belmont, California) and testosterone stimulation. Transgenic over expression of Insl3 failed to restore normal testicular descent in Hoxa10 or Gnrhr deficient males. Histological evaluation did not reveal any differences in Insl3 transgenic gubernacula in either mutant. In mutant females Insl3 over expression resulted in transabdominal descent of the ovaries to the low abdominal position with the subsequent development of inguinal hernia. Expression of androgen receptor, insulin-like 3 receptor and Hoxa10 was not affected after incubation of neonatal gubernacular cells with insulin-like 3 or androgen. The results suggest that insulin-like 3 is sufficient to direct the first transabdominal phase of testicular descent in the absence of hypothalamic-pituitary-gonadal axis signaling or Hoxa10 but their presence is important for inguinoscrotal testicular descent.

Effects of orchiopexy on congenitally cryptorchid insulin-3 knockout mice.

Insulin-3 (Insl3) knockout mice exhibit isolated, bilateral, high intra-abdominal cryptorchidism. If left in this position until adulthood, these testes will deteriorate to the Sertoli-cell-only state, leading to infertility in 100%. We examined the effect of orchiopexy in this genetically engineered animal model. A total of 160 testes from 80 male offspring of Insl3 F crosses underwent either no orchiopexy (29 testes), sham surgery (25 testes), 1-stage Fowler-Stephens scrotal orchiopexy (57 testes) or primary orchiopexy into a low abdominal, subcutaneous pouch (49 testes). A group of postoperative mice underwent fertility testing 3 months postoperatively. At 6 to 9 months postoperatively the testes were harvested and histologically analyzed. Testes were atrophic in 100% (25 of 25) of the sham group, 91% (52 of 57) of the Fowler-Stephens orchiopexy group and 33% (16 of 49) of the subcutaneous pouch group (testis weight less than 50 mg.). Fertility testing was done in 30 mice (sham 5, Fowler-Stephens orchiopexy 17 and subcutaneous pouch 8). Infertility was secondary to bilateral testicular atrophy (sham 5 of 5, Fowler-Stephens orchiopexy 13 of 17), spermatogenic maturation arrest (subcutaneous pouch 8 of 8) and ductal obstruction [normal spermatogenesis with epididymis devoid of sperm] (Fowler-Stephens orchiopexy 2 of 17). Fertility with normal spermatogenesis was observed in 2 of 17 Fowler-Stephens orchiopexy mice, both of which were Insl3 knockout mice. Intrascrotal orchiopexy can rescue these congenitally cryptorchid Insl3 knockout testes from their intra-abdominal fate of Sertoli-cell-only and lead to fertility. The results suggest that orchiopexy has a crucial and central role in preservation of spermatogenesis.