Development Of Testicles Research Articles

Subnutrition in different pregnancy stages affects IGF-1 serum concentration, its receptor expression and testicular morphology in pubertal male rats

In order to study the effects of subnutrition during different pregnancy stages on testicle development and its impact on both, IGF-1 serum concentration and its receptor production in Sertoli, Leydig and myoid cells, twenty-four primiparous female Wistar rats (331.9 ± 12.4 g body weight) were mated by the same male rat. Four groups were established: (CC) fed ad libitum during the entire pregnancy, (RC) restricted for days 0–10 of pregnancy, restricted from day 11 of pregnancy till parturition and (CR) restricted during the entire pregnancy (RR). All males from all groups were fed without restrictions since birth until puberty at day 40. During restriction stages, animals were offered 50% of the ad libitum daily food intake. Both, body and testicular weight were affected depending on which pregnancy stage the treatment was applied. On the other hand, IGF-1 production and the total Sertoli cell number was lower at day 40 if the treatment had been applied during either the entire pregnancy or in the second half. IGF-1 receptor expression was affected in Leydig cells if restriction was applied, regardless of which restricted group was studied. However, in myoid cells IGF-1 receptor expression increased when treatment was applied during the entire pregnancy. In conclusion, subnutrition in the different pregnancy stages affects body development, testicular weight and testicular morphology in pubertal male rats.

Perineal Ectopic Testis in One and A Half Year Old Child As A Rare Congenital Anomaly: A Case Report

Ectopic testis is described as an abnormality of testicle development in which one or both testicles aren’t descending through the testicle normal pathways. Among all newborns with undescended testis, only 1% are diagnosed as ectopic testis. In this case, an 18 months old boy was presented to hospital with chief complaint of impalpable testis dextra. Phsical examination showed the right testis was not palpable in the scrotum and perineum. Ultrasonography examination showed a right testis in the perineum with normal volume and vascularization. Right orchidopexy was performed to correct the location of the testis. Early diagnostic of ectopic testis must be done through anamnesis, physical examination, and advanced examination. Limited faciliiesy and lack of parental knowledge make the patients come late to health facility. The conclusion of this study is knowledge among parents and skills of health workers concerning congenital anomaly especially undescensus testis should be improved.

Multipathway synergy promotes testicular transition from growth to spermatogenesis in early-puberty goats

BackgroundThe microscopic process of postnatal testicular development in early-puberty animals is poorly understood. Therefore, in this study, 21 male Yiling goats with average ages of 0, 30, 60, 90, 120, 150 and 180 days old (each age group comprised three goats) were used to study the changes in organs, tissues and transcriptomes during postnatal testicle development to obtain a broad and deep insight into the dynamic process of testicular transition from growth to spermatogenesis in early-puberty animals.ResultsThe inflection point of testicular weight was at 119 days postpartum (dpp), and the testicular weight increased rapidly from 119 dpp to 150 dpp. Spermatozoa were observed in the testis at 90 dpp by using haematoxylin–eosin staining. We found from the transcriptome analysis of testes that the testicular development of Yiling goat from birth to 180 dpp experienced three stages, namely, growth, transition and spermatogenesis stages. The goats in the testicular growth stage (0–60 dpp) showed a high expression of growth-related genes in neurogenesis, angiogenesis and cell junction, and a low expression of spermatogenesis-related genes. The goats aged 60–120 dpp were in the transitional stage which had a gradually decreased growth-related gene transcription levels and increased spermatogenesis-related gene transcription levels. The goats aged 120–180 dpp were in the spermatogenesis stage. At this stage, highly expressed spermatogenesis-related genes, downregulated testicular growth- and immune-related genes and a shift in the focus of testicular development into spermatogenesis were observed. Additionally, we found several novel hub genes, which may play key roles in spermatogenesis, androgen synthesis and secretion, angiogenesis, cell junction and neurogenesis. Moreover, the results of this study were compared with previous studies on goat or other species, and some gene expression patterns shared in early-puberty mammals were discovered.ConclusionsThe postnatal development of the testis undergoes a process of transition from organ growth to spermatogenesis. During this process, spermatogenesis-related genes are upregulated, whereas neurogenesis-, angiogenesis-, cell junction-, muscle- and immune-related genes are downregulated. In conclusion, the multipathway synergy promotes testicular transition from growth to spermatogenesis in early-puberty goats and may be a common rule shared by mammals.

Assessment of immunocontraceptive vaccine for population control: evaluation of a recombinant fusion GnRH vaccine in mice

Abstract Gonadotropin-releasing hormone (GnRH) plays a pivotal role in regulating the reproductive endocrine system. Accumulated lines of evidence indicated that GnRH immunocontraception vaccine is a potential tool for control and management of animal population. However, the poor immunogenicity of GnRH peptide has limited its efficacy and field application. In the present study, a modified antigen, containing 8 GnRH repeats and immunostimulatory fusion protein, was formulated an oil-based MONTANIDE™ ISA 206 VG adjuvant to enhance the immunogenicity of the GnRH vaccine. The vaccine was vaccinated in 4-week-old male ICR mice (n = 10) and boosted twice, 4 and 8 weeks, respectively after the primary immunization. Mice injected with saline served as the unimmunized control (n = 10). Results demonstrated that the serum GnRH-specific antibody in vaccinated mice was significantly (p < 0.05) increased 5 weeks, peaked at 12 weeks, and remained high until 18 weeks after the primary immunization. In comparison with the control, vaccinated mice had significantly (p < 0.05) reduced serum testosterone concentration (0.856 ± 0.411 v.s. 160.77 ± 1. 865 ng/ml) and hampered development of testicles (weight and spermatogenesis) at 24 weeks after the primary immunization. Finally, a mating test indicated that the conception rate of female mice housed with vaccinated and unvaccinated males was 29% and 75%, respectively. The recombinant GnRH vaccine may be a potential approach for controlling animal population through immunocontraception.

Embryonic Exposure to Bisphenol A Impairs Primordial Germ Cell Migration without Jeopardizing Male Breeding Capacity.

A large amount of chemicals are released to the environment each year. Among them, bisphenol A (BPA) is of utmost concern since it interferes with the reproductive system of wild organisms due to its capacity to bind to hormone receptors. Additionally, BPA epigenotoxic activity is known to affect basic processes during embryonic life. However, its effects on primordial germ cells (PGCs) proliferation and migration, both mechanisms being crucial for gametogenesis, remain unknown. To investigate the effects of BPA on PGCs migration and eventual testicle development, zebrafish embryos were exposed to 100, 2000 and 4000 µg/L BPA during the first 24 h of development. Vasa immunostaining of PGCs revealed that exposure to 2000 and 4000 µg/L BPA impaired their migration to the genital ridge. Two pivotal genes of PGCs migration (cxcr4b and sdf1a) were highly dysregulated in embryos exposed to these doses, whereas DNA methylation and epigenetic marks in PGCs and their surrounding somatic cells were not altered. Once embryos reached adulthood, the morphometric study of their gonads revealed that, despite the reduced number of PGCs which colonized the genital ridges, normal testicles were developed. Although H3K9ac decreased in the sperm from treated fishes, it did not affect the progeny development.

Reproductive characteristics of wild boar males (Sus scrofa) under different environmental conditions

The wild boar population has been on a permanent increase over the last decades, causing conflicts with the requirements of modern human society. Existing effort to stabilize wild boar numbers generally fails with one of the causes being the high reproductive potential of wild boar. The aim of this study was to assess the onset of sexual maturity in wild boar males with regard to age, physical frame and environmental conditions on the basis of testicle development and sperm production. This study assessed the dimensions of gonads and the occurrence of sperm in boars caught during common hunts. Environmental conditions were found as an important factor for growth and sexual maturity of wild boar males. The body weight was a more important factor for sperm production than the age of young wild boar males. The weight threshold for sperm production in the testes was 29 kg of live weight, which corresponds to 6 months of age on average. This study has proven that environmental conditions are a significant factor affecting the physical development of male wild boars, more specifically the growth rate of their body frames and the onset of sexual maturity. In a better quality environment boars grow faster and enter puberty at an earlier age. Poor food supply and/or high hunting pressure result in slower body and testicular growth, as well as the production of sperm at a later age (approx. 2-3 months later).

Endocrine disruptive compounds and male reproduction

Abstract Endocrine disruptors (EDs) are chemical substances that affect physiological processes in the organism via hormonal regulation. The EDs are present in the environment and objects of everyday use. They are often detected in food, particularly released from packaging of canned food, but also from plastic water bottles, and they are also found in cosmetics and fertilizers. They are commonly detected in children's toys, banknotes, receipts and many more objects. Permanent and long-term utilization of EDs has harmful effects on human reproductive health mainly by interference with sex hormone synthesis and mechanism of action. The endocrine disruptors show many negative effects on male reproductive system. Any change during synthesis or activity of sex hormones can cause abnormal reproduction, including developmental anomalies of the sexual system, disruption of testicular development or deterioration of sperm quality. Mainly the impact on the development of testicles in prenatal and early postnatal period can be crucial for reproductive health in males. This review provides an overview of the EDs and their possible impact on reproductive health in males with focus on sperm quality and development of testicles.

Characterization and evolution analysis of Wt1 and StAR genes in Andrias davidianus

Wt1 and StAR are two multifunctional genes that play an important role in sexual differentiation, especially in development of testicles and spermatogenesis, but the studies of amphibians are rare. In this study, we have cloned and characterized the complete cDNA of Wt1 and StAR in Andrias davidianus. The Wt1 has two isoforms, encoding 416 aa or 419 aa protein with a conserved zinc finger structure region. The StAR encodes 287 aa protein with a conserved domain containing putative lipid binding sites. The two genes showed high homology among amphibians by phylogenetic analysis. Molecular evolution analysis indicated that Wt1 gene underwent positive selection, while StAR gene showed no positive selection. Tissue expression patterns revealed that Wt1 expression was higher in liver, moderate in testis and kidney, low in the rest of the tissues, while StAR expression was higher in testis, moderate in kidney and brain, low in the rest of the tissues. Moreover, compared to female and reversal-female, Wt1 and StAR both showed higher expression level in male and reversal-male. Our results suggest the important role of Wt1 and StAR in sexual development of Andrias davidianus, and also provide information for functional study of amphibian Wt1 and StAR.

Influence of chronic intrauterine hypoxia on development of testicles of newborns

Influence of chronic intrauterine hypoxia on development of testicles of newborns

Investigating the relationship between precocious puberty and obesity: a cross-sectional study in Shanghai, China

ObjectivesObesity is reported to be closely relevant to early sexual development but the relationship between sexual precocity and obesity or central obesity is still inconsistent, especially in boys. We aimed...

Changes in plasma steroid hormones and gonadal histology associated with sexual maturation in wild southern hake (Merluccius australis)

A detailed study of gametes development and characterization of plasma sex steroid hormones during the maturation cycle was performed for the first time in the southern hake (Merluccius australis). Fish were caught in the inland waters of the Reloncaví Sound, Interior Sea of Chiloé, Chile. Samples of gonads and blood were collected for histology and sex steroid hormone (17 β-estradiol, 11-ketotestosterone and 17,20 βdihydroxy-4-pregnen-3-one) analysis, respectively. Sex steroid hormone quantification was performed using enzyme-immunoassay (ELISA). Results showed that M. australis males and females have asynchronous development of testicles and ovaries, in all stages of maturation. Most spawning fish were found during the spring months. Regarding the sex steroid hormones, serological fluctuations of 17 β-estradiol and 11- ketotestosterone were found during gonadal maturation of M. australis. These hormones are the main hormones responsible for vitelogenesis and spermatogenesis processes, respectively. Conversely, 17,20 β-dihydroxy-4- pregnen-3-one did not show any serological fluctuation in females and males. Further studies involving gonadotropins, 17,20 β,21-trihydroxy-4-pregnen-3-one and vitellogenin quantification are required in order to obtain a more complete description of the reproductive physiology of wild and farmed M. australis.

CLINICAL AND ANATOMICAL ASPECTS OF TESTICLE DESCENT INTO THE SCROTUM

By means of morphological methods of examination it was found that gubernaculum of the testis, which rudiments appear at the beginning of the 6th week of embryogenesis, plays a leading role in the testicle descent into the scrotum. Accelerated formation of gubernaculum of the testis in 5-8 monthold fetuses which is proved by the prevalence of smooth muscular cells over the elements of the connective tissue, is one of the main factors of heterochrony in the testicle development and their further descent into the scrotum. The ventral protrusion of the peritoneum vaginal process appears at the end of the 8th week of embryogenesis; formation of the process is prior to caudal displacement of the testes. The fusion of the visceral plate of the peritoneum vaginal process with protein membrane of the testis and over testis occurs in 6-7 month-old fetuses. Disorders in the process of fusion of the layers of processus vaginalis peritonei in 9-10-month-old fetuses may be anatomic precondition of congenital inguinoscrotal hernia development.

The possible role of zinc in the etiopathogenesis of endometriosis

Purpose of investigation: Aim of the study was to evaluate the possible involvement of zinc in the complex pathogenic process behind the onset and perpetuation of endometriotic lesions. To study the level of zinc serum between a group of patients affected by endometriosis and a group of healthy patients. Materials and Methods: The study included 86 women: 42 patients whose histodiagnosis had revealed pelvic endometriosis and 44 healthy patients. The authors measured the serum zinc concentration for all patients. Results: The group of patients with endometriosis presented serum zinc concentration of 1,010 ± 59.24 μg/l. The observation group presented a serum zinc concentration of 1,294 ± 62.22 μg/l. Conclusion: The results showed that serum zinc levels in women with endometriosis are decreased and this seems to actually confirm that this micro-element can possibly affect the multifactorial pathogenesis of the disease. As a matter of fact, zinc interferes with many biological processes, among which inflammation and immunity, which seem to be the base of the development of the lesions. Therefore, the authors believe that this hypothesis requires more attention and further investigation to determine its reasonableness. If the results are confirmed, this study opens up future prospects as for the treatment of endometriosis, taking into account also the role of zinc in the onset of male sterility and the development of testicles. Zinc could in fact be used as marker to detect women at high risk of endometriosis and for the elaboration of a new treatment for sterility, from which these women often suffer.

Multinucleated cells are involved in normal development and apoptosis in mouse testes

Multinucleated cells are present in impaired spermatogenesis and in the senescent testis. Following accumulating evidence from our previous studies on the identification of multinucleated cells during normal testicle development, the current study further investigated the possible mechanism and role of these multinucleated cells. Healthy male Kunming mice were used in the present study. The association between multinucleated cells and cell apoptosis were analyzed using TUNEL analysis and immunohistochemistry. The results showed that multinucleated cells are widespread in the testicular tissue of seminiferous tubules on postnatal days 23, 27, 30, 33, 36, 40, 47, 50 and 54 suggesting that these cells are involved in the process of normal development of mouse testis. Histochemical analysis revealed a lack of proliferating cell nuclear antigen, cyclin D1 protein expression in multinucleated cells, suggesting that these cells are not involved in the G1 and S phases of the cell cycle and cell proliferation. Increased expression of Bax and caspase 3 was detected, revealing that multinucleated cells may be associated with cell apoptosis during testicular development. To the best of our knowledge, this study demonstrated for the first time that multinucleated cells are present during normal testicular development and may be associated with spermatogonial stem cell apoptosis. Therefore, multinucleated cells may be important in the spermatogenesis process.

Growth and development peculiarities of testicles in postpubertal period in inbred mice lines PT and CBA/Lac

The goal of this study is to perform a comparative genetic investigation of testicle development during the postpubescence period (from days 70 to 90 of life) in the inbred mice lines PT and CBA/Lac. Interlinear differences in the body and testicular weight, serum testosterone concentration, number of epididymal spermatozoa, area of testicular epithelium, semeniferous tubule lumen, and insulae of Leydig cells were analyzed. It was found that the morphological and histomorphometric parameters of testicles in males from the PT line compared to the males of the CBA/Lac line did not reach a definitive stage with the end of the post-pubescence period and kept on developing until day 90 of life. Therefore, genetic differences remain in the postpubertal testicular development of laboratory mice.

An association study of 20 candidate genes with cryptorchidism in Siberian Husky dogs

Cryptorchidism (CO) as a common developmental defect in purebred dogs causes health concerns of reduced fertility and increases risk of testicular malignancies. A total of 49 single nucleotide polymorphisms (SNPs) discovered from 20 candidate genes was investigated to analyse their associations with CO in Siberian Huskies. The sibling-transmission disequilibrium test on 38 discordant full-sibs revealed seven SNPs in the collagen type II alpha 1 (COL2A1) gene were significantly (p < 0.05) or suggestively (p < 0.10) associated with CO. Further analyses showed that only one SNP (rs23358342) in this gene remained suggestively significant (p < 0.1) on a data set of full-sibs with additional related dogs, but not significant on all 156 Siberian Huskies. Based on the statistical results and the involvement of COL2A1 in the testicle development and descent, we could not exclude COL2A1 as a potential candidate gene for CO in Siberian Huskies. Further studies are necessary to clarify these results from our relatively small sample size.

Reproducción del pez erizo, Diodon holocanthus (Pisces: Diodontidae) en la plataforma continental del Pacífico Central Mexicano

Diodon holocanthus is an important economic and ecological species of the demersal fish community, caught as bycatch from local shrimp fishery. The reproductive biology of this long-spine porcupinefish has not yet been described, and reproductive season, the sex ratio, length distribution, length at first gonad maturity, and the gonad macro and microscopic features are described. A total of 400 organisms, ranging from 5.0 to 40.3 cm (average 18.4 cm) total length, were caught from the continental shelf of the Central Mexican Pacific, from December 1995 and December 1998. Sex ratio was 1:0.86 females to males (n = 253). The length at which 50% of the individuals showed maturing gonads was 19.7 cm for females and 20.1 cm for males. Length of the smallest organism with ripe gonads was 12.2 cm for females and 13 cm for males. Four gonadal maturation stages were found in both sexes, and five oocyte development phases were identified. The oocyte development pattern is of asynchronous type, which means the species can reproduce several times a year. Testicle development is lobular type, as in most teleost fishes. Monthly mean values of the gonad-somatic index suggest the reproduction activity peaks in June, and September-December.

Effect of a gonadotropin-releasing factor vaccine on follicle-stimulating hormone and luteinizing hormone concentrations and on the development of testicles and the expression of boar taint in male pigs

The objective of this study was to determine the effect of using a gonadotropin-releasing factor (GnRF) vaccine on follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations in plasma, the size of testicles, and the expression of boar taint in male pigs. Vaccinated pigs were compared with surgically castrated pigs and entire males. Pigs were randomly assigned to three treatment groups: surgically castrated during the first week of life (T01, n = 274), immunized twice during the fattening period with a GnRF vaccine, the first when 13 to 14 wk of age and the second when 20 to 21 wk of age (T02, n = 280), and entire males (T03, n = 56). From a subgroup of both T01 and T02 and from all pigs of group T03, blood samples were collected immediately before second vaccination (T02) and again before slaughter at either 24 to 25 or 26 to 27 wk of life to determine the plasma concentrations of LH and FSH. Testicles were removed after slaughter and their size was determined. Meat and fat samples from all pigs of T02 and T03 as well as 25% of the pigs of T01 were examined with the cold cooking and fat melting test. Immediately before the second vaccination (T02 only), LH and FSH concentrations were not significantly different between T02 and T03. However, LH and FSH concentrations were significantly higher in T01 compared with T02 and T03. Before the first slaughter date, LH and FSH concentrations were significantly lower in T02 than in T03. Testicle size was significantly lower in T02 compared with that in T03. In T02, 98% (235 of 239) of the samples were rated negative for boar taint by the cooking test, whereas in T03, 94% (48 of 51) were rated positive. In the fat melting test, 97% of T02 were rated negative and 3% (7 pigs) were rated positive, including the pigs tested positive in the cold cooking test. In T03, 94% were rated positive. All pigs (7 of 239) in T02 that were positive for boar taint in the cooking or melting test and that were tested had androstenone and skatole concentrations in backfat below threshold levels of 1 μg/g and 0.2 μg/g, respectively.

EFFECTS OF ZERANOL IMPLANTATION ON GROWTH, FEED CONVERSION, TESTICULAR DEVELOPMENT AND BEHAVIORAL TRAITS OF YOUNG BULLS FED FOR SLAUGHTER

An experiment was conducted to determine whether implantation with zeranol would reduce the aggressive behavior and probability of producing dark-cutting carcasses that characterize slaughter bulls. Thirty-six bull calves were allocated to each of four treatments – nonimplanted bulls, steers castrated at an average age of 101 d, bulls implanted with 36 mg zeranol at an average of 101, 170, 263 and 319 d of age and bulls implanted on the latter three dates only. The results reported include observations of weight gains, linear measurements, scrotal circumferences, serum testosterone concentrations, feed consumption, feed efficiency ratios and behavioral traits. Bulls exceeded steers in weight gain during a feedlot test and in body length after 140 d on feed, but neither implantation treatment significantly affected the growth of bulls. Feed consumption and conversion efficiency were lower in steers than in bulls, but were not significantly affected by implantation. Scrotal circumference measurements and serum testosterone concentrations suggested that implantation reduced testicle development during the preweaning and early postweaning periods, but that this effect diminished or disappeared during the later postweaning period. Implantation depressed aggressive and sexual activity between days 111 and 155 of the feedlot test. When evaluated at 13–14 mo of age, both implanted groups reacted to preslaughter mixing of nonfamiliar animals with equivalent head bunting to, but less mounting activity than, nonimplanted bulls. At 15–16 mo of age, however, the implanted bulls exhibited more head bunting than nonimplanted bulls, and the early implanted group exhibited fully equivalent mounting activity to nonimplanted bulls. The dark-cutting carcass condition was associated with mounting activity during preslaughter lairage. Key words: Slaughter bull, zeranol, growth, linear measurements, testicular development, behavior

Influence of Dietary Cadmium Level and Supplemental Zinc on Cadmium Toxicity in the Bovine 1 2 3

Growth rate, feed consumption, water intake, and testicle development decreased progressively as the concentration of Cd in the diet increased. Blood hemoglobin decreased slightly when 40 to 160 ppm Cd in the diet were consumed, but increased sharply when higher levels of Cd (640 and 2560 ppm) were fed. Calves fed 640 or 2560 ppm Cd exhibited unthrifty appearance; rough hair coat; severe body dehydration; dry and scaly skin; loss of hair; mouth lesions; edematous, shrunken, and scaly scrotum; sore and enlarged joints; impaired sight; and liver and kidney damage. Feeding 40 to 160 ppm of Cd from 9 to 20 weeks of age resulted in few clinical symptoms. There was 100% mortality in calves given 2560 ppm Cd, with death occurring in 2 to 8 weeks. At the 640 ppm level there was some mortality. When Cd was removed from the diet, a very severely affected calf recovered to normal appearance with a substantial quantity of live, but mostly abnormal, sperm later obtained from the epididymis. The data suggest that addition of zinc partially offset the effects of Cd on calf performance. Kidneys and livers contained the highest concentration of Cd.