Epididymidal Spermatozoa Research Articles

Multiple ageing effects on testicular/epididymal germ cells lead to decreased male fertility in mice

In mammals, females undergo reproductive cessation with age, whereas male fertility gradually declines but persists almost throughout life. However, the detailed effects of ageing on germ cells during and after spermatogenesis, in the testis and epididymis, respectively, remain unclear. Here we comprehensively examined the in vivo male fertility and the overall organization of the testis and epididymis with age, focusing on spermatogenesis, and sperm function and fertility, in mice. We first found that in vivo male fertility decreased with age, which is independent of mating behaviors and testosterone levels. Second, overall sperm production in aged testes was decreased; about 20% of seminiferous tubules showed abnormalities such as germ cell depletion, sperm release failure, and perturbed germ cell associations, and the remaining 80% of tubules contained lower number of germ cells because of decreased proliferation of spermatogonia. Further, the spermatozoa in aged epididymides exhibited decreased total cell numbers, abnormal morphology/structure, decreased motility, and DNA damage, resulting in low fertilizing and developmental rates. We conclude that these multiple ageing effects on germ cells lead to decreased in vivo male fertility. Our present findings are useful to better understand the basic mechanism behind the ageing effect on male fertility in mammals including humans.

Biallelic mutations in RNA-binding protein ADAD2 cause spermiogenic failure and non-obstructive azoospermia in humans.

What are some pathogenic mutations for non-obstructive azoospermia (NOA) and their effects on spermatogenesis? Biallelic missense and frameshift mutations in ADAD2 disrupt the differentiation of round spermatids to spermatozoa causing azoospermia in humans and mice. NOA is the most severe cause of male infertility characterized by an absence of sperm in the ejaculate due to impairment of spermatogenesis. In mice, the lack of the RNA-binding protein ADAD2 leads to a complete absence of sperm in epididymides due to failure of spemiogenesis, but the spermatogenic effects of ADAD2 mutations in human NOA-associated infertility require functional verification. Six infertile male patients from three unrelated families were diagnosed with NOA at local hospitals in Pakistan based on infertility history, sex hormone levels, two semen analyses and scrotal ultrasound. Testicular biopsies were performed in two of the six patients. Adad2 mutant mice (Adad2Mut/Mut) carrying mutations similar to those found in NOA patients were generated using the CRISPR/Cas9 genome editing tool. Reproductive phenotypes of Adad2Mut/Mut mice were verified at 2 months of age. Round spermatids from the littermates of wild-type (WT) and Adad2Mut/Mut mice were randomly selected and injected into stimulated WT oocytes. This round spermatid injection (ROSI) procedure was conducted with three biological replicates and >400 ROSI-derived zygotes were evaluated. The fertility of the ROSI-derived progeny was evaluated for three months in four Adad2WT/Mut male mice and six Adad2WT/Mut female mice. A total of 120 Adad2Mut/Mut, Adad2WT/Mut, and WT mice were used in this study. The entire study was conducted over 3 years. Whole-exome sequencing was performed to detect potentially pathogenic mutations in the six NOA-affected patients. The pathogenicity of the identified ADAD2 mutations was assessed and validated in human testicular tissues and in mouse models recapitulating the mutations in the NOA patients using quantitative PCR, western blotting, hematoxylin-eosin staining, Periodic acid-Schiff staining, and immunofluorescence. Round spermatids of WT and Adad2Mut/Mut mice were collected by fluorescence-activated cell sorting and injected into stimulated WT oocytes. The development of ROSI-derived offspring was evaluated in the embryonic and postnatal stages. Three recessive mutations were identified in ADAD2 (MT1: c.G829T, p.G277C; MT2: c.G1192A, p.D398N; MT3: c.917_918del, p.Q306Rfs*43) in patients from three unrelated Pakistani families. MT1 and MT2 dramatically reduced the testicular expression of ADAD2, likely causing spermiogenesis failure in the NOA patients. Immunofluorescence analysis of the Adad2Mut/Mut male mice with the corresponding MT3 mutation showed instability and premature degradation of the ADAD2 protein, resulting in the spermiogenesis deficiency phenotype. Through ROSI, the Adad2Mut/Mut mice could produce pups with comparable embryonic development (46.7% in Adad2Mut/Mut versus 50% in WT) and birth rates (21.45 ± 10.43% in Adad2Mut/Mut versus 27.5 ± 3.536% in WT, P = 0.5044) to WT mice. The Adad2WT/Mut progeny from ROSI (17 pups in total via three ROSI replicates) did not show overt developmental defects and had normal fertility. N/A. This is a preliminary report suggesting that ROSI can be an effective treatment for infertile Adad2Mut/Mut mice. Further assisted reproductive attempts need to be carefully examined in humans during clinical trials. Our work provides functional evidence that mutations in the ADAD2 gene are deleterious and cause consistent spermiogenic defects in both humans and mice. In addition, preliminary results show that ROSI can help Adad2Mut/Mut to produce biological progeny. These findings provide valuable clues for genetic counselling on the ADAD2 mutants-associated infertility in human males. This work was supported by the National Natural Science Foundation of China (32000587, U21A20204, and 32061143006), and the National Key Research and Developmental Program of China (2019YFA0802600 and 2021YFC2700202). This work was also supported by Institute of Health and Medicine, Hefei Comprehensive National Science Center, Hefei, China. The authors declare no competing interests.

An Approach for Investigating Sexual Maturity in Wild Boar Males: Testosterone and 17β-Estradiol Analysis.

Simple SummaryWild boar numbers have increased constantly over the last three decades, as have their related conflicts with modern society. For this reason, wild boars have become a frequent topic of discussion. This article describes and explains the concentrations of the two main sexual steroids, testosterone and estradiol, as well as our effort to define threshold levels to recognize the sexual maturation of wild boar males and differentiate between immature and adult boars. With the help of additional analyses on spermatozoa and morphological data, it was shown that prepubertal boars at 8 months of age could be clearly differentiated from postpubertal boars, showing significantly lower concentrations of hormones. Wild boar males older than 11 months of age, in contrast, presented hormonal values like adults. Before the completion of their first year, wild boars are physiologically able to reproduce and may take part in reproduction. The high hormonal concentrations at the end of the breeding season suggest that the mating period could last longer than usually supposed, shifting farrowing into the summer.Analyses of sexual steroid hormones in wild boars are rarely described. Testosterone (T) and 17β-estradiol (E2) concentrations are useful to recognize sexual maturation. As threshold values for this species are unknown, additional parameters are required. A total of 127 blood samples from wild boar males were collected to measure T and E2. Age and weight were recorded. Thirty-one epididymides were sampled too. Males were sorted into pre-and postpubertal groups based on the absence/presence of spermatozoa in epididymides and on morphological data following previous results. Forty-four males were prepubertal: the mean age and weight were 10 months and 23 kg, respectively. They showed no spermatozoa. The mean concentrations of T and E2 were 1.2 ± 1.2 ng/mL and 39.7 ± 120.3 pg/mL, respectively. Sixty-six males were postpubertal, twenty-nine of which presented spermatozoa. Their mean concentration of T was 7.6 ± 6.3 ng/mL and E2 was 664.3 ± 250.4 pg/mL. Seventeen samples could not be defined; the hormone concentrations between the two groups suggested a transitional phase consistent with puberty. Wild boars before 12 months of age had high hormone levels like older boars, indicating that they could attempt to reproduce. Hormones at the end of the mating season (January) were high so that reproduction could occur thereafter, shifting farrowing from spring to summer.

Ontogeny of TRα1 expression in the mouse testis and epididymis during postnatal development.

Thyroid hormone (T3 ) acts on the testis via thyroid hormone receptor alpha 1 (TRα1), though the cellular localization of TRα1 in testis remains controversial. Studies on the presence of TRα1 in the epididymis are also lacking. The present study, therefore, examined the cellular localization and expression pattern of TRα1 in testis and epididymis of Parkes mice during postnatal development. Immunohistochemical results showed localization of TRα1 in interstitial and tubular compartments of the testis all through the development. On postnatal day (PND) 14, only leptotene spermatocytes showed TRα1-immunoreactivity in the testis, while at PND 28, 42, and 90, a diverse staining pattern for TRα1 was seen in almost all the seminiferous tubules mainly in leptotene spermatocytes, round and elongating spermatids, and in Leydig cells. Further, qRT-PCR and immunoblot analyses showed that TRα1 was expressed in the testis at the transcript as well as protein level throughout the postnatal development. TRα1 was also seen in principal cells of the epididymis, with maximal expression at PND 90. TRα1 was also present in cauda epididymidal spermatozoa of adult mice at PND 90. The results suggest that TRα1 is expressed in the testis and epididymis and that it may help to regulate the spermatogenic process and male fertility.

Paternal cadmium exposure increases the susceptibility to diet-induced testicular injury and spermatogenic disorders in mouse offspring.

The impairments of gestational cadmium (Cd) exposure on testicular development and male fertility in offspring have been reported. Here, we investigated the effect of paternal low-concentration cadmium exposure on testicular development and spermatogenesis in offspring. Five-week-old male mice were exposed to cadmium chloride (100mg/L) in drinking water for 20 weeks. Results presented that Cd did not affect the testicular histology and sperm count in mice. After mating with untreated females, pregnant mice and pups were then evaluated. No significant difference in the rate for successful pregnancy and the body weight of pups was observed in Cd-exposed mice compared to the controls. Male offspring were given with a chow and high-fat diet from postnatal day (PND) 35 to PND70. Our data indicated that high-fat diet obviously decreased No. of sperm in epididymides of adult offspring due to paternal Cd exposure. Testicular histology revealed that the percentage of seminiferous tubules in stages IX-XII and the atypical residual bodies positive tubules in CdH (paternal cadmium exposure and pubertal high-fat diet) group were higher than these in CdC (paternal cadmium exposure and pubertal chow diet) group. Further analysis demonstrated that high-fat diet markedly accelerated testicular apoptosis, as determined by TUNEL assay and immunostaining for cleaved caspase-3, in male offspring due to paternal Cd exposure. Collectively, high-fat diet exacerbates the damage of testicular development and spermatogenesis in offspring due to paternal cadmium exposure.

Rosmarinic acid reverses the effects of metronidazole-induced infertility in male albino rats.

Rosmarinic acid (RA) is a natural antioxidant that has many biological activities. In the present study we investigated the potential of RA to reverse the negative effects of the widely used antibiotic and antiprotozoal agent metronidazole (MTZ), which is known to induce reversible male infertility. Two doses of RA (5 and 15mg kg-1) were studied in sexually mature rats with and without MTZ-induced infertility. Rats were intraperitoneally injected with 5mg kg-1 RA or 15mg kg-1 RA (in distilled water) and, 45min later, they were intraperitoneally injected with 40mg kg-1 MTZ (in distilled water). Cauda epididymidal sperm suspensions were used to assess sperm count, motility and morphology. Histological and ultrastructural studies were performed on the testes and cauda epididymidis. In rats in which infertility was not induced, neither dose of RA affected the parameters assessed. However, in sexually mature rats in which infertility was induced by 40mg kg-1 MTZ, RA at both 5 and 15mg kg-1 ameliorated the damaging effects of MTZ on final bodyweight (30 days later), sperm motility and morphology. Only 5mg kg-1 RA, and not 15mg kg-1 RA, improved the harmful effects of MTZ on the sperm count and testis ultrastructure. The findings of the present study have considerable clinical implications and suggest a possible use for RA to reverse the negative effects of MTZ on male fertility, the male reproductive system and spermatogenesis.

Aspects of Male Reproductive Toxic Effects of Quassia amara L.: Histopathological and Ultrastructural Study in Mouse

Quassia amara is a Brazilian medicinal plant traditionally used as an herbal remedy for a variety of diseases. Quassin is the major secondary chemical compound in it, which is under investigation as an anti-malarial compound. There are preliminary studies implicating Q. amara in male reproductive toxicity. Hence, this elaborate study was undertaken to find the male reproductive toxic effects of Q. amara and quassin. Methanolic extract of Q. amara bark and quassin were administered to male mice for 35 days. The cauda epididymidal sperm, testis and epididymis were subjected to analysis adopting light and transmission electron microscopy. Sperm counts, motility and viability decreased. The incidence of sperm with abnormal morphologies increased. There was premature loss of germ cells from the seminiferous tubules, which correlated with Sertoli cell pathology. The Leydig cells were vacuolated, suggesting a hypo-androgen status. The epididymis indicated severe histopathological changes, including reflection of a mitogenic / tumorigenic effect of Q. amara . Thus, this study indicates that Q. amara , when applied as a therapeutic, could be severely toxic to male reproductive mechanisms and the principal mechanism of action appears to be through Leydig cells. Quassin, the major secondary metabolite responsible for the therapeutic potential of Q. amara , is also the one causative of the male reproductive toxic effects. Thus, this study substantiates the claim that Q. amara is toxic to male reproductive system.

Aspects of Male Reproductive Toxic Effects of Quassia amara L.: Histopathological and Ultrastructural Study in Mouse

Quassia amara is a Brazilian medicinal plant traditionally used as an herbal remedy for a variety of diseases. Quassin is the major secondary chemical compound in it, which is under investigation as an anti-malarial compound. There are preliminary studies implicating Q. amara in male reproductive toxicity. Hence, this elaborate study was undertaken to find the male reproductive toxic effects of Q. amara and quassin. Methanolic extract of Q. amara bark and quassin were administered to male mice for 35 days. The cauda epididymidal sperm, testis and epididymis were subjected to analysis adopting light and transmission electron microscopy. Sperm counts, motility and viability decreased. The incidence of sperm with abnormal morphologies increased. There was premature loss of germ cells from the seminiferous tubules, which correlated with Sertoli cell pathology. The Leydig cells were vacuolated, suggesting a hypo-androgen status. The epididymis indicated severe histopathological changes, including reflection of a mitogenic/tumorigenic effect of Q. amara . Thus, this study indicates that Q. amara , when applied as a therapeutic, could be severely toxic to male reproductive mechanisms and the principal mechanism of action appears to be through Leydig cells. Quassin, the major secondary metabolite responsible for the therapeutic potential of Q. amara , is also the one causative of the male reproductive toxic effects. Thus, this study substantiates the claim that Q. amara is toxic to male reproductive system.

Abnormal pairing of X and Y sex chromosomes during meiosis I in interspecific hybrids of Phodopus campbelli and P. sungorus.

Hybrid sterility plays an important role in the maintenance of species identity and promotion of speciation. Male interspecific hybrids from crosses between Campbell's dwarf hamster (Phodopus campbelli) and the Djungarian hamster (P. sungorus) exhibit sterility with abnormal spermatogenesis. However, the meiotic phenotype of these hybrids has not been well described. In the present work, we observed the accumulation of spermatocytes and apoptosis of spermatocyte-like cells in the testes of hybrids between P. campbelli females and P. sungorus males. In hybrid spermatocytes, a high frequency of asynapsis of X and Y chromosomes during the pachytene-like stage and dissociation of these chromosomes during metaphase I (MI) was observed. No autosomal univalency was observed during pachytene-like and MI stages in the hybrids; however, a low frequency of synapsis between autosomes and X or Y chromosomes, interlocking and partial synapsis between autosomal pairs, and γ-H2AFX staining in autosomal chromatin was observed during the pachytene-like stage. Degenerated MI-like nuclei were frequently observed in the hybrids. Most of the spermatozoa in hybrid epididymides exhibited head malformation. These results indicate that the pairing of X and Y chromosomes is more adversely affected than that of autosomes in Phodopus hybrids.

Inhibin B as a Marker of Sertoli Cell Damage and Spermatogenic Disturbance in the Rat

This study was designed to determine the effects of Compound A on spermatogenesis including assessment of inhibin B levels and on fertility in the male rat over a 15 to 19 weeks treatment and a 19 weeks treatment-free period in control and 30, 60, and 180 mg/kg dose groups (n = 22/group). Compound A in a dose-dependent manner induced various degrees of spermatogenic alterations compatible with Sertoli cells being the primary target, for example, inter- and intracellular Sertoli cell vacuolization and altered cellular morphology followed by germ cell degeneration and marked reduction of epididymidal sperm numbers. Blood-testis barrier remained intact (electron microscopy and hyperosmotic fixation test) until germ cells disappeared. Mating behavior and weights of androgen-dependent prostate and seminal vesicles remained unaffected. Inhibin B levels correlated only with moderate to severe spermatogenic alterations. Ten animals with inhibin B levels below detection limit were encountered and five of these animals were fertile in week 19 but following 19 weeks without treatment, another five animals were rendered infertile and inhibin B levels remained undetectable. In the rat, inhibin B only reflects major spermatogenic alterations and markedly reduced inhibin B levels might indicate irreversibility of these alterations and even infertility.

241 METHYLATION PROFILE OF XIST GENE EXON 1 IN BOVINE SPERMATOGENIC CELLS

Mammalian embryos undergo two waves of genome reprogramming, the first in the zygote, when paternal and maternal genomes are demethylated and, shortly thereafter, remethylated, and the second in the primordial germ cells. It is believed that remethylation is reestablished in male germ cells before birth; however, it is not clear when and how this process occurs in the bovine. Thus, this work aimed to verify whether epigenetic reprogramming occurs during spermatogenesis by evaluating the methylation profile of XIST gene exon 1 in different spermatogenic cells. Spermatocytes, elongated spermatids, and spermatozoa from the epididymis head and tail were collected from bovine testes obtained from a slaughterhouse. The DNA was extracted from the collected cells and treated with bisulfite. The treated DNA was amplified through nested PCR, and the product was inserted on a vector and cloned in bacteria. The plasmid DNA was extracted and sequenced. The sequences of the experiment were compared with the sequence of XIST gene from GenBank, and those that presented a bisulfite conversion rate of ≥95% and a homology of ≥97% with the sequence from GenBank were used. To compare the methylation pattern among groups, the total percentage of methylated CpG was calculated in each replicate and each group. The methylation pattern was compared using Kruskal-Wallis and Mann–Whitney tests because the data did not show normality. All data were compared using the Prophet Program, version 5.0 (1996; BBN Systems and Technologies, Cambridge, MA, USA), and are shown as the mean ± SEM. The significance level used was P < 0.05. The spermatocytes, elongated spermatids, and spermatozoa from the epididymis head and tail groups presented 15.70 ± 14.54%, 1.96 ± 1.96%, 74.09 ± 6.78%, and 45.09 ± 20.19% of methylation, respectively. The epididymis head group was more methylated than the spermatocyte and elongated spermatid groups (P < 0.01). When arranged in two groups, one with spermatocytes and elongated spermatids, and the other with epididymidal spermatozoa, and compared, it was observed that the methylation level was different (P < 0.01) between them. These results suggest that epigenetic reprogramming is still occurring during spermatozoa formation.

Modification of the Testicular Function in Laboratory Male Mice during Social Interactions: Effect of Female Presence

The count of spermatozoa in both caudal epididymides, percentage of abnormal spermatozoon heads and of mobile spermatozoa, body weight, weights of the testes and caudal epididymides were evaluated in adult inbred males (PT and CBA/Lac) kept with females for 5 days. Male mice of the same genotypes and age separated from females served as controls. In males kept with females, the weights of the testes increased in PT male mice, the percentage of rapidly mobile spermatozoa increased in CBA/Lac mice, and body weights decreased in males of both genotypes. The morphometric and spermatogenic parameters in laboratory mice were modulated by the presence of a female, but the effect was determined by the male genotype.

Die Quetschung des Samenstrangs eignet sich beim Kaninchen nicht zur Ausschaltung der Hodenfunktion

The aim of this study was to evaluate the effect of three different methods for squeezing of the spermatic cord as bloodless castration in rabbits according to the "Burdizzo"-method used for ruminants. In 18 anaesthetized male rabbits (group 1-3) spermatic cords were squeezed twice using three different methods according to Burdizzo: using a Pean haemostat for 3 minutes (group 1, n=10) or 10 minutes (group 2, n=4) or by use of a Doyen intestine clamp for 3 minutes (group 3, n=4). Seven males serving as controls underwent surgical castration under general anaesthesia. Animals were daily examined until day 7, and on days 14 and 90. Blood samples for testosterone measurement were taken on days 1 and 90. On day 90, all animals of groups 1-3 were surgically neutered and testis examined histologically in comparison with group 4. A swelling of the squeezing site was obvious in all animals of group 1-3 which was - like pain reaction - most obvious in group 1. Temporary changes in testicular consistency, as well as inflammation signs were observed in testes, epididymides and spermatic cords. During the course of the study, testes size increased (p<0.0001) independently of the group. Testosterone was within the physiological range in group 1-3 and differed significantly from group 4 (p=0.0002). Histology revealed normal spermatogenesis and fully elongated sperm in testes and epididymides. None of the three bloodless methods used led to testicular shrinking, basal testosterone concentration and disturbed spermatogenesis which would be a suitable marker for testicular atrophy indicating castration. Although bloodless castration seems to be an interesting alternative to surgery in rabbits, none of the methods used was successful in inducing castration effects.

Effects of radiographic contrast media on domestic cat epididymidal sperm

Laparoscopic artificial insemination has an important role in felid conservation but it is costly and includes surgical risk. Therefore, radiographic contrast medium combined with non-surgical transcervical AI to verify intrauterine gamete placement could be a viable alternative. Gamete-rescued fresh and frozen-thawed sperm were extended with one of two commercial contrast media (nonionic and ionic), with osmolarity adjusted to 320–330 mOsm, or feline optimized culture medium (control). Percent motility, forward progression status, and acrosomal integrity were recorded every 30 min for 4 h. Sperm penetration abilities were assessed by coincubating treated sperm with conspecific in vitro matured oocytes for 18 to 20 h, and presumptive zygotes and embryos were fixed and stained to determine sperm penetration and fertilization rate. There was reduced motility and acrosomal integrity in frozen-thawed versus fresh sperm (P < 0.05). Neither radiographic contrast medium induced adverse effects on fresh sperm motility relative to control medium (P > 0.05), but motility of frozen-thawed sperm decreased when treated with nonionic radiographic contrast medium compared to control medium (P < 0.05). There were no differences in acrosomal integrity between radiographic contrast and control media in fresh (P > 0.05) or frozen sperm (P > 0.05). Neither radiographic contrast media decreased the numbers of morphologically normal sperm (P > 0.05) or reduced the ability of domestic cat sperm to penetrate (P > 0.05) or fertilize (P > 0.05) conspecific oocytes. Ionic radiographic contrast medium can be added to fresh or frozen-thawed domestic cat sperm with no adverse effect on motility, morphology, acrosomal integrity or oocyte penetration rates, and thus may be used to facilitate further development of transcervical AI procedures.

Antioxidant Defence System of Boar Cauda Epididymidal Spermatozoa and Reproductive Tract Fluids

Antioxidants secreted by the reproductive tract protect spermatozoa against the toxic effects of reactive oxygen species (ROS) after ejaculation. This study aimed at characterizing the level of antioxidant protection in boar cauda epididymidal spermatozoa and fluids of the cauda epididymidis, vesicular and prostate glands. Also, this study investigated the effect of a 5-h period of dialysis on the antioxidant capacity of boar seminal plasma. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione transferase (GST) and phospholipid hydroperoxide glutathione peroxidase (PHGPx) activities were monitored in the cauda epididymidal spermatozoa or reproductive tract fluids. Also, the concentrations of total glutathione (GSH + GSSG), L-ergothioneine (ERT) and l-ascorbate and the total antioxidant status (TAS) of the fluids were measured. It was found that the cauda epididymidal spermatozoa exhibited high SOD activity and relatively low activity of PHGPx. The relative amounts of GPx, GR and GST activities in the cauda epididymidal spermatozoa were negligible, whereas CAT activity was undetectable. Greater SOD activity was found in the fluids of the cauda epididymidis and prostate gland. Furthermore, the prostate gland fluid appeared to be the main source of CAT activity in the seminal plasma, whereas the highest level of GPx activity was derived from the cauda epididymidal fluid. The reproductive tract fluids exhibited negligible amounts of GR and GST activities. It seemed that the significant amounts of GSH + GSSG, ERT and L-ascorbate in the reproductive tract fluids could have an ameliorative effect on the level of TAS in the seminal plasma. Dialysis had a marked effect on the total antioxidant capacity of the seminal plasma, which was manifested in greater activity of SOD and GPx. The findings of this study confirmed that the scavenging potential of the seminal plasma is dependent on the contributions of different antioxidants, originating in various fluids of boar reproductive tract.

Pubertal cadmium exposure impairs testicular development and spermatogenesis via disrupting testicular testosterone synthesis in adult mice

Cadmium (Cd) is a well-known testicular toxicant. However, the effects of pubertal Cd exposure on testicular development and spermatogenesis remained to be elucidated. The present study investigated the effects of pubertal Cd exposure on testicular development and spermatogenesis. Male CD-1 mice were intraperitoneally injected with CdCl(2) (1mg/kg) daily from postnatal day 35 (PND35) to PND70. As expected, pubertal Cd exposure significantly decreased the number of spermatozoa in epididymides. In addition, pubertal Cd exposure markedly reduced the weights of testes, epididymides and prostate and seminal vesicle in adult mice. A significant decrease in serum and testicular testosterone (T) was observed in mice exposed to Cd during puberty. Moreover, pubertal Cd exposure markedly reduced mRNA and protein levels of testicular StAR, P450scc, P450(17alpha) and 17beta-HSD. Taken together, these results suggest that the decreased testicular T synthesis might partially contribute to pubertal Cd-induced impairment on testicular development and spermatogenesis in mice.

Impact of experimental diabetes and insulin replacement on epididymal secretory products and sperm maturation in albino rats

The present study is aimed to explore the impact of experimental diabetes and insulin replacement on epididymal secretory products, sperm count, motility, and fertilizing ability in albino rats. Prepubertal and adult male Wistar strain rats were made diabetic with a single intraperitoneal injection of streptozotocin (STZ), at 120 and 65 mg/kg body weight for prepubertal and adult rats, respectively. After 3 days of STZ administration, insulin was given to a group of diabetic rats at a dose of 3 U/100 g body weight, subcutaneously and killed after 20 days of treatment. STZ-diabetes significantly reduced the epididymal tissue concentrations of testosterone, androgen-binding protein, sialic acid, glycerylphosphoryl choline, and carnitine, suggesting its adverse effects on the secretory activity and concentrating capacity of epididymal epithelium. Impaired cauda epididymidal sperm motility and fertility (in vivo) of STZ-diabetic rats imply the defective sperm maturation. Insulin replacement prevented these changes either partially or completely. From the above findings, it is evident that STZ-diabetes has an adverse effect on sperm maturation, which may be due to the decrease in the bioavailability of testosterone and epididymal secretory products.

Effect of 1-(2, 4-dichlorobenzyl)-1H-indazole-3-carboxylic acid (DICA) on the sex organs of the male laboratory mouse.

Oral administration (50 mg/kg body weight/day, for 28 days) of 1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxylic acid (DICA) induced significant reduction in testicular weight with suppression of spermatogenesis. The seminiferous tubules were devoid of spermatozoa and contained only Sertoli cells, spermatogonia, spermatocytes and several multinucleated giant cells. The Leydig cells, however, remained unaffected in treated animals. The drug also induced significant decrease in the levels of testicular RNA and protein; DNA level, however, remained unaltered. Epididymis in DICA-treated mice presented normal histology except that the lumen contained sperm debris; cauda epididymidal spermatozoa were immotile and often fragmented. DICA treatment caused no change in the level of fructose in the seminal vesicle. DICA-induced alterations were reversible and within 56 days of drug withdrawal the reproductive organs returned to their normal state.

Prostaglandin F2 alpha-induced changes in the sex organs of the male laboratory mouse.

Administration (3 mg/kg body weight/day, for 21 days) of prostaglandin F2 alpha (PGF2 alpha) caused marked suppression of spermatogenesis and significant reduction in the weights of the testis, epididymis and accessory sex glands. The seminiferous tubules were devoid of spermatozoa and contained only Sertoli cells, spermatogonia, spermatocytes and occasionally spermatids; several multinucleated giant cells were observed in the lumen of the tubules. The Leydig cells were atrophied. The levels of RNA, DNA and protein in the testis were, however, unaffected by drug therapy. In drug-treated mice the epididymal epithelium presented a degenerate appearance; the lumen was generally devoid of spermatozoa and contained mainly exfoliated immature germ cells and sperm debris; cauda epididymidal spermatozoa, when present, were immotile and fragmented. PGF2 alpha treatment also caused significant decrease in the levels of sialic acid in the caput and cauda epididymides and of fructose in the seminal vesicle. The results suggest that the regressive changes induced by PGF2 alpha in the reproductive organs of the mouse are due to the interference with the secretion of androgen. The alterations induced in the reproductive organs by administration of PGF2 alpha were reversible and 56 days after drug withdrawal the organs returned to their normal state.

Effect of 1-p-Chlorobenzyl-1H-Indazol-3-Carboxylic Acid (AF 1312/TS) on the Sex Organs of the Male Laboratory Mouse

Oral administration (500 mg/kg body weight/day, for 28 days) of 1-p-chlorobenzyl-1H-indazol-3-carboxylic acid (AF 1312/TS) induced suppression of spermatogenesis without adversely affecting the Leydig cells. The seminiferous tubules were almost depopulated and contained only Sertoli cells and spermatogonia. The drug also induced significant decrease in the levels of testicular RNA and protein; DNA level, however, remained unaltered. Regressive histological changes were also noted in the epididymides of drug-treated mice. Cauda epididymidal spermatozoa from drug-treated mice were immotile and fragmented. AF 1312/TS caused no alteration in the level of fructose in the seminal vesicle. The drug-induced alterations were reversible, and 56 days after drug withdrawal the reproductive organs returned to their pretreatment state. The results suggest that AF 1312/TS selectively suppresses spermatogenesis without interfering with the endocrine functions of the testis.