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PubMed1987

Müllerian inhibiting substance in sex-reversed dogs.

In normal males, Müllerian Inhibiting Substance (MIS), produced by testes during an embryonic critical period, is thought to induce regression of the Müllerian duct system, including the oviducts and uterus. In XX sex-reversed dogs, an apparent contradiction has been reported: The uterus persists in the presence of testes or ovotestes. The objective of this study is to determine whether testes of XX male and ovotestes of true hermaphrodite dogs produce MIS, and to examine the anatomy of Müllerian duct derivatives of affected dogs for evidence of regression. Gonadal samples were tested for MIS activity in a bioassay. The mean MIS activity score of XX males was similar to that of normal XY males and significantly greater than that of normal XX females. The mean MIS activity score of XX true hermaphrodites was intermediate between normal XX females and XY males. Within the true hermaphrodite group, ovotestes in which the proportion of testicular tissue was greater than or equal to 1/2 had higher MIS scores than those in which the proportion of testicular tissue was less than 1/2. XX males had a well-developed epididymis adjacent to each testis, but no oviducts. In true hermaphrodites, the oviduct regressed and an epididymis was present when greater than or equal to 1/2 of the adjacent ovotestis was testicular, and MIS activity in that gonad was high. A few ovotestes with intermediate levels of MIS activity had both an oviduct and an epididymis. Regression of the oviductal portion of the Müllerian duct system was positively correlated to the amount of testicular tissue and the MIS activity of the gonad, as would be predicted by Jost's original hypothesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2005

Identification of immunodominant autoantigens in rat autoimmune orchitis.

Infection and inflammation of the genital tract are amongst the leading causes of male infertility. Experimental autoimmune orchitis (EAO) in the rat serves as a model for the investigation of inflammatory testicular impairment. In this study, experiments were conducted to identify the molecules that are responsible for eliciting the autoimmune attack on the testis. EAO was induced in in-bred Wistar rats by active immunization with testis homogenates (EAO group I). Development of disease was observed using histological techniques and a new non-invasive three-dimensional (3D) imaging technology for in vivo monitoring, termed flat-panel volumetric computed tomography (fpvCT). Examination of control and EAO testes demonstrated the superior image quality of high-resolution fpvCT. A proteomics approach using 2D SDS-PAGE and immunoblotting analysis with EAO sera identified 12 spots. Seven were subsequently identified by mass spectrometry as heat shock proteins 60 (Hsp60) and 70 (Hsp70), disulphide isomerase ER-60, alpha-1-anti-trypsin, heterogeneous nuclear ribonucleoprotein H1 (hnRNP H1), sperm outer dense fibre major protein 2 (ODF-2), and phosphoglycerate kinase 1. Hsp70, ODF-2, hnRNP H1, and ER-60 were identified by all EAO sera studied. To test the capacity of the identified proteins to elicit testicular autoimmune disease, recombinant proteins were used either individually or in combination to immunize rats (EAO group II). In all groups, the incidence of EAO was 25%. Inflammatory-type (ED1+) and resident (ED2+) macrophages, lymphocytes (CD45RA+), and dendritic cells (Ox-62+) were strongly increased in EAO group II animals, comparable to the testes of EAO I rats. Pre-immunization with a low dose of recombinant Hsp 70, hnRNP H1 or ODF-2 before induction of EAO with testis homogenate significantly delayed the onset of EAO but could not prevent disease. The identification of testicular autoantigens will allow a better understanding of disease pathogenesis and could provide a basis for the development of novel therapies for inflammation-based male infertility.

Animals↗
PubMed1996

[The effect of a low molecular weight synthetic humic substance on selected reproductive parameters of male rats].

Influences of the low molecular humic substance HS 1500 on parameters of organs (testis weight, epididymis weight), FSH-, and LH-levels in plasma as well as on the spermatogenesis of male rats were studied. After a daily oral application of 1000 mg/kg b.w. and 2000 mg/kg b.w., respectively over a period of 60 days (40th to 100th day of life) only 2 animals of the high dose group were observed with bilateral testicular atrophy. Despite of the two animals with testicular atrophy no significant differences between treated and control rats were observed with respect to testis morphology and spermatogenesis. There is no evidence whether the differences between the hormone levels and the testicular atrophy revealed is regarded to a HS 1500-effect or not. But otherwise a direct influence of HS 1500 can be ruled out with high certainty. Possibly because of the thin covering layer on the gastrointestinal mucous membrane formed by HS 1500, the absorption of nutritive substances is inhibited. Therefore the growth of sensitive organs like testis and epididymis, in the development period, can be decreased. Nevertheless, even after long time application the spermatogenesis is not influenced.

Administration, Oral↗
PubMed1990

Testicular feminization syndrome in the neonate.

If we see a young, phenotypically female patient with an XY karyotype, it is of great importance to differentiate between the testicular feminization syndrome and gonadal dysgenesis. Patients with testicular feminization will always have normal testes, which are situated either in the ovarian fossa or in the inguinal canal. Patients with gonadal dysgenesis always have streak gonads. The risk of developing a malignancy in an abnormally located testis is very low, certainly before puberty, whereas the risk for dysgenetic gonads to develop a malignancy is high. Testes in patients with testicular feminization have an important endocrine function in puberty, whereas in gonadal dysgenesis patients they do not. For these reasons, in patients with testicular feminization, one should not remove the testes until the completion of puberty, whereas in patients with gonadal dysgenesis removal should be performed immediately upon recognition of the disorder.

Androgen-Insensitivity Syndrome↗
PubMed1996

[Indication for surgery of pediatric testicular and funicular hydroceles in view of natural course].

PURPOSE: The purpose of this study is to confirm the definite indication for surgery of pediatric testicular and funicular hydroceles in view of natural course. METHODS: During the period from 1978 to 1994, we encountered 160 hydroceles in 149 pediatric patients. Patients ages ranged from 5 days after birth to 13 years and the mean follow-up periods was 4.7 years. We investigated the indication for surgery of pediatric hydroceles in six points of view: value of an aspiration of hydroceles, of what testicular or funicular or both, communication, size, age and testicular development. RESULTS: Nevertheless, of 160 hydroceles, 66 (41%) were performed an aspiration of hydroceles, the aspiration of hydrocele was ineffective in the majority of patients. Common hydroceles in neonates and infants required no specific treatment, as the majority of hydrocele resolve spontaneously, however surgical treatment was required for a communicating large hydrocele that had been often attacked by aspiration and appeared at older age. Funicular hydroceles were more difficult to spontaneous healing. Ipsilateral testis manifests a well-developed comparing control material. CONCLUSION: The indication for surgery of pediatric hydroceles were as follows: 1) hydroceles complicated by a inguinal hernia or cryptorchidism, 2) hydroceles appeared at older age and not resolved during 2-3 years over, 3) giant communicating funicular and testicular hydroceles present with an/hindrance for daily life.

Child↗
PubMed1984

Lactosaminoglycans synthesized by mouse male germ cells are fucosylated by an epididymal fucosyltransferase.

We have studied the synthesis of protein-bound carbohydrates in differentiating male germ cells in the mouse. Spermatocytes and spermatids synthesize asparagine-linked and high-molecular-weight glycopeptides as the major classes of protein bound carbohydrates. Asparagine-linked glycopeptides were found to be mainly composed of the complex bi-antennary type as shown by affinity chromatography on concanavalin-A Sepharose; high-molecular-weight glycopeptides were represented by nonfucosylated lactosaminoglycans since they were metabolically labeled with [14C]glucosamine but not with [3H]fucose, did not bind to DEAE-cellulose, and were susceptible to endo-beta-galactosidase. Labeling with galactose oxidase/Na B3H4 technique demonstrated that lactosaminoglycans were present on the surface of differentiating germ cells and of testicular and epididymal spermatozoa. Since lactosaminoglycans from germ cells and testicular spermatozoa were not retained on a column of fucose-binding lectin, it was concluded that these molecules do not contain fucose. On the other hand, epididymal spermatozoa lactosaminoglycans bound to the lectin and therefore contained fucose. A soluble fucosyltransferase, capable of transferring fucose to germ cell lactosaminoglycans, was found to be present in the epididymis but not in the testis. These data show that developing germ cells synthesize nonfucosylated lactosaminoglycans which are probably preserved throughout spermiogenesis. We suggest that these molecules are fucosylated in vivo by a fucosyltransferase secreted by the epididymal epithelium.

Amino Sugars↗
PubMed1980

Blood-testis barrier in men with idiopathic hypogonadotropic eunuchoidism and postpuberal pituiary failure.

Immature-type Sertoli cells in the testes of idiopathic hypogonadotropic eunuchoidism (17-30 years of age) had no specialized junctions. The specialized Sertoli junctions that blocked the penetration of lanthanum were formed six months to two years after hCG treatment (5000 IU twice a week) in patients of hypogonadotropic eunuchoidism. In two patients with postpubertal pituitary failure (one had a ectopic pinealoma, irradiated one year ago, and the other had a pituitary adenoma, hypophysectomized four years ago), the ultrastructural integrity of these Sertoli junctions was maintained. Therefore, it may be suggested that the development of the blood-testis barrier is dependent on gonadotropins, but the maintenance of the blood-testis barrier is not.

Adenoma↗
PubMed1990

Sex differentiation in the hagfish Eptatretus stouti.

A detailed study was made of sex differentiation in three anteroposteriorly distributed body regions of the long gonadal fold in young Pacific hagfish (Eptatretus stouti) from 12.4 to 45 cm in length. In general, the posterior region, adjacent to the cloaca, remained undifferentiated, and only in specimens more than 28 cm long was there development of this region into a differentiated testis. On the other hand, the anterior gonadal region of all specimens under 20 cm developed continually and progressively through stages that included cystic nests of cells derived from the germinal epithelium, acquisition of follicular investments around these cells, growth of these young oocytes and break-up of their original follicular groupings, and, finally, in larger specimens, vitellogenesis. Although the earliest oocytes formed in cyst-like nests of cells, later oocytes were derived individually directly from the germinal epithelium. In larger specimens, in which testicular development occurred in the posterior part of the gonad, the anterior gonad involuted, leaving a thin structure that lacks germ cells. There were numerous exceptions to this general description of events, indicating a certain degree of lability of determination of a particular gonadal region to either male or female differentiation. Some earlier stages of female differentiation could occur in the posterior gonadal region of a few smaller animals. Some posteriorly located ovotestes (differentiated elements of both sexes) developed in a few specimens between 16 and 21 cm in length, but were not seen in larger animals. Some testicular follicles appeared in the anterior gonadal regions of three specimens between 20 and 25 cm in length, but not in specimens larger than that. Three hermaphroditic specimens between 29 and 33 cm in length were found in which there was a well-differentiated testis posteriorly and a well-differentiated ovary (vitellogenic eggs) anteriorly. Questions of hermaphroditism, lability of sex determination, and possible epigenetic influences on these phenomena are taken up in the discussion. Since this study provides the first correlation of stages of sex differentiation with animal length, it forms the basis for experimental approaches in E. stouti to analysis of mechanisms of sex determination and differentiation.

Animals↗
PubMed1995

Sperm, a source of estrogen.

This review article discusses a novel nontraditional site of estrogen synthesis and the potential targets of estrogen action within the male reproductive system. Our laboratories have recently demonstrated that developing spermatids in several species contain aromatase, the cytochrome P450 enzyme responsible for converting androgens into estrogens. The enzyme was localized by immunocytochemistry and the protein's presence was confirmed by Western blot analysis. Northern blot analysis and in situ hybridization were used to corroborate the presence of mRNA for aromatase. It appears that the aromatase message precedes the synthesis of the protein, and the protein remains in the spermatids several days after the message disappears. The enzyme is located along the tail of newly released sperm and is active in the epididymal sperm as well as in the developing germ cells of the testis. This unique discovery is the basis for our overall hypothesis that estrogen, synthesized by sperm, plays a role in the regulation of epididymal function proportional to the number of sperm being transported. The presence of an estrogen source within the ductal lumen is of special importance to the study of epididymal function because the regulatory mechanisms in this region remain unclear, particularly for the efferent ductules and initial segment regions, although estrogen receptors have been identified in the ductal epithelium. An understanding of the role that estrogen plays in the function of the epididymis may provide benefits in several areas including the treatment of abnormalities in epididymal function, the potential development of a male contraceptive, and insight into the causes of adult epididymal lesions induced by neonatal exposure to estrogenic compounds such as diethylstilbestrol.

Animals↗
PubMed1997

Investigation of the potential role of the germ cell complement in control of the expression of transferrin mRNA in the prepubertal and adult rat testis.

Iron is required for the normal development of germ cells during spermatogenesis. Because these cells have no direct access to systemic iron, there exists a shuttle system involving production and secretion of the iron-transporting protein transferrin by the Sertoli cells. Previous reports using cultures of immature Sertoli cells exposed to adult germ cells, or in vivo studies involving germ cell depleted adult rat testes, concluded that production of transferrin by Sertoli cells is modulated by germ cell complement. In the present study we have used in situ hybridisation with cRNA probes directed against the 5' and 3' ends of transferrin mRNA to examine the pattern of expression of transferrin in the immature and adult rat testis. Adult rats were treated with ethane dimethane sulphonate or methoxyacetic acid (MAA) to manipulate their testosterone levels or germ cell complement respectively. Initial findings obtained using the 3' probe showed a decrease in transferrin mRNA associated with round spermatid depletion. However, these data were not confirmed by in situ hybridisation when the 5' probe was used. The specificity of the probes was examined using Northern blotting and the 3' probe was found to hybridise to the germ cell transcript for hemiferrin even under conditions of high stringency. Examination of immature and pubertal rat testes by in situ hybridisation using the 5' transferrin-specific probe found that as early as 14 days of age the level of expression of transferrin mRNA was clearly different between tubules, and the mRNA appeared to be expressed in Leydig cells on and after day 31. In the adult rat testis, maximal expression of transferrin mRNA was found at stages VIII-XIV, calling into question the interpretation of the results of some previous studies showing expression of transferrin mRNA at all stages of the spermatogenic cycle. This stage-specific pattern of expression was not altered by acute germ cell depletion using MAA. However, Northern blot analysis showed a statistically significant increase in transferrin mRNA expression at 7 days after MAA treatment when pachytene spermatocytes were depleted from tubules at all stages of the spermatogenic cycle at which transferrin is normally expressed. In conclusion, we found that transferrin mRNA expression was not modulated by round spermatids as has been reported previously but that meiotic germ cells may influence expression of transferrin at specific stages of the spermatogenic cycle.

Animals↗
PubMed1997

Essential functions of Pax-5 (BSAP) in pro-B cell development.

Pax-5 codes for the transcription factor BSAP which is expressed in all B-lymphoid tissues in addition to the developing central nervous system and testis. Within the B-lymphoid lineage, Pax-5 expression is already detected in the earliest B cell progenitors and persists up to the mature B cell stage. Targeted inactivation of the Pax-5 gene in the mouse germline revealed a differential dependency of fetal and adult B-lymphopoiesis on this transcription factor. Pax-5 is required for the differentiation of the earliest B-lineage-committed precursor cells in the fetal liver. In contrast, B cell development in the adult bone marrow progresses up to an early pro-B cell stage in the absence of Pax-5 function. The expression of CD19, Ig alpha (mb-1) and N-myc is severely reduced in Pax-5-deficient pro-B cells. These BSAP target genes are, however, unlikely to explain the early developmental block based on their known function in B cell development. Moreover, VH-to-DHJH rearrangements at the immunoglobulin heavy-chain locus are approximately 50-fold reduced in Pax-5-deficient pro B-cells, while the DH-to-JH rearrangements occur at a normal frequency. However, the expression of rearranged mu heavy-chain transgenes does not allow Pax-5-deficient pro-B cells to develop further to the pre-B cell stage. Together these data demonstrate therefore that B cell development in the Pax-5 deficient bone marrow is arrested at an early pro-B cell stage which is not yet responsive to pre-B cell receptor signaling.

Animals↗
PubMed2002

Differential expression of the retinoic acid-metabolizing enzymes CYP26A1 and CYP26B1 during murine organogenesis.

We recently cloned the murine homologue of Cyp26B1, a novel retinoic acid (RA)-metabolizing enzyme and showed that its gene expression pattern is unique from that of Cyp26A1 during early embryogenesis. Here, we complete this comparative expression analysis from embryonic day (E) 12 to postnatal stages. Cyp26B1 expression was found in developing tendons and precartilaginous elements and in perichondrium by E14.5, while Cyp26A1 expression was restricted to extremities of rib and vertebral cartilage. Cyp26A1 and Cyp26B1 were expressed, in the distal epithelium and mesenchyme of the limbs and genital tubercle, respectively. High Cyp26B1 expression was found in craniofacial areas undergoing morphogenetic growth, whereas Cyp26A1 message was restricted to the mouth and dental epithelium. Cyp26A1 alone was expressed in the developing neural retina, while both genes were co-expressed in the retinal pigment epithelium. Cyp26B1 was specifically expressed in the developing hindbrain (pons, cerebellum) and forebrain (striatum, hippocampus), with forebrain expression persisting postnatally. In addition, Cyp26B1 was expressed at specific levels of the differentiating upper and lower thoracic spinal cord, adjacent to the cervical and lumbar regions that express the RA-synthesizing enzyme RALDH-2. In viscera, Cyp26B1 transcripts were detected in the developing lung, kidney, spleen, thymus and testis, whereas Cyp26A1 transcripts were found in the diaphragm and outer stomach mesenchyme. Cyp26B1 was also specifically expressed in dermis surrounding the developing hair follicles. Regulated RA metabolism may therefore be required in many developing systems.

Animals↗
PubMed2003

Cryptorchidism and testicular neoplasia.

OBJECTIVE: Traditionally there is a concern about the possibility of developing testicular tumors as a consequence of undescended testis. This study was conducted to investigate the correlation between testicular tumors and undescended testis. METHODS: Medical records of all patients with testicular germ cell cancer were seen and examined at the Princess Basma Teaching Hospital, Jordan University of Science and Technology, Irbid, Jordan, between 1990 and 2000 (group 1) for any evidence of undescended testis. All males with undescended testis attending the infertility clinic during the period 1999-2001 (group 2) were re-evaluated for any evidence of testicular tumors. The operative records of all patients who had surgery for undescended testis during the past 30 years (group 3) were reviewed and the patients were contacted to see if any of them developed testicular tumor as expected. RESULTS: Forty-four patients with testicular germinal cell tumors; mean age at diagnosis were 32.6 years (range 20-50) were identified. All patients had unilateral involvement and none of them were found to have tumors in undescended testis. The tumor was in the scrotum in all patients. None of the 117 infertile patients with undescended testis had clinical or ultrasonic evidence of testicular tumors. Two thousand nine hundred and nineteen patients had an operation for undescended testicle in the past 30 years, average of 97.3 operations annually. Median age at surgery for undescended testis was 7.7 years (range 2-29 years). None of the 2071 patients who were traceable developed testicular tumor. CONCLUSION: We found no evidence to support that patients with undescended testis are at a higher risk than the general population to develop testicular cancer.

Adult↗
PubMed1995

A conserved family of elav-like genes in vertebrates.

A large family of genes encodes proteins with RNA recognition motifs that are presumed to bind RNA and to function in posttranscriptional regulation. Neural-specific members of this family include elav, a gene required for correct differentiation and maintenance of neurons in Drosophila melanogaster, and a related gene, HuD, which is expressed in human neuronal cells. I have identified genes related to elav and HuD in Xenopus laevis, zebrafish, and mouse that define a family of four closely related vertebrate elav-like genes (elrA, elrB, elrC, and elrD) in fish, frogs, and mammals. In addition to protein sequence conservation, a segment of the 3'-untranslated sequence of elrD is also conserved, implying a functional role in elrD expression. In adult frogs, elrC and elrD are exclusively expressed in the brain, whereas elrB is expressed in brain, testis, and ovary. During Xenopus development, elrC and elrD RNAs are detected by late gastrula and late neurula stages, respectively, whereas a nervous system-specific elrB RNA species is expressed by early tadpole stage. Additional elrB transcripts are detected in the ovary and early embryo, demonstrating a maternal supply of mRNA and possibly of protein. These expression patterns suggest a role for different elav-like genes in early development and neuronal differentiation. Surprisingly, elrA is expressed in all adult tissues tested and at all times during development. Thus, the widely expressed elrA is expected to have a related function in all cells.

Amino Acid Sequence↗
PubMed1990

Development of mouse germ cells in cultures of fetal gonads.

Mouse gonadal tissue was studied under various conditions of in vitro culture, with the aim of clarifying some of the somatic-cell influences that regulate the development of germ cells in the mammalian gonad. Gonadal ridges, with or without the adjacent mesonephric region, were removed from mouse embryos 10.5-12.5 days post coitum (dpc). In an organ culture system, the female ridges showed good development, with no masculinization. All germ cells entered meiosis at the expected time. Although some oocytes entered the growth phase, many primordial follicles were observed. 11.5- and 12.5-day male ridges formed testis cords, and the germ cells developed as T-prospermatogonia. In 10.5-day ridges, cells resembling Sertoli cells differentiated but did not form testis cords, and the germ cells entered meiosis. We conclude that full differentiation of the supporting cell lineage was not achieved when culture was begun at 10.5 dpc; our findings suggest that immature Sertoli cells neither form testis cords nor inhibit the entry of germ cells into meiosis. When the ridges were fragmented and cultured in gas-permeable dishes, the somatic cells grew out as a monolayer on which the germ cells rested. Under these conditions male germ cells did not enter meiosis and did not survive for more than a few days. Female germ cells entered meiosis. In contrast to the organ culture system, many of the surviving oocytes entered the growth phase during the second week of culture, reaching diameters of up to 60 microns. This suggests that normal follicular cell investment may play a crucial role in maintaining the oocyte in a state of developmental arrest. The growing oocytes showed the oocyte-specific expression of the enzyme glucose phosphate isomerase. It seems that the initiation and maintenance of both oocyte growth and oocyte-specific gene expression can take place in the absence of normal follicular cell investment.

Animals↗
PubMed2002

The genetics of male undermasculinization.

A review of the genetics of male undermasculinization must encompass a description of the embryology of the genital system. The dimorphism of sex development consequent upon the formation of a testis and the subsequent secretion of hormones to impose a male phenotype is highlighted. Thus, an understanding of the causes of male undermasculinization (manifest as XY sex reversal, complete and partial) includes reviewing the genetic factors which control testis determination and the production and action of testicular hormones. The study of disorders of male sex development has contributed substantially to knowledge of normal male development before birth. This knowledge has been complimented in recent years by the use of targeted murine gene disruption experiments to study the sex phenotype, although murine and human phenotypes are not always concordant. The investigation of disorders associated with male undermasculinization of prenatal onset is described briefly to complete the review.

Animals↗