Voluntary Exercise Attenuates Hyperhomocysteinemia, But Does not Protect Against Hyperhomocysteinemia-Induced Testicular and Epididymal Disturbances.

The hyperhomocysteinemia (HHcy) is toxic to the cells and associated with several diseases. Clinical studies have shown changes in plasma concentrations of Hcy after physical exercise. This study aimed to assess the effect of HHcy on testis, epididymis and sperm quality and to investigate whether voluntary exercise training protects this system against damage caused by HHcy in Swiss mice. In this study, 48 mice were randomly distributed in the control, HHcy, physical exercise, and HHcy combined with physical exercise groups. HHcy was induced by daily administration of dl-homocysteine thiolactone via gavage throughout the experimental period. Physical exercise was performed through voluntary running on the exercise wheels. The plasma concentrations of homocysteine (Hcy) and testosterone were determined. The testes and epididymis were used to assess the sperm count, histopathology, lipoperoxidation, cytokine levels, testicular cholesterol, myeloperoxidase, and catalase activity. Spermatozoa were analyzed for morphology, acrosome integrity, mitochondrial activity, and motility. In the testes, HHcy increased the number of abnormal seminiferous tubules, reduced the tubular diameter and the height of the germinal epithelium. In the epididymis, there was tissue remodeling in the head region. Ultimately, voluntary physical exercise training reduced plasma Hcy concentration but did not attenuate HHcy-induced testicular and epididymal disturbances.

High-fructose diet during puberty alters the sperm parameters, testosterone concentration, and histopathology of testes and epididymis in adult Wistar rats.

The consumption of fructose has increased in children and adolescents and is partially responsible for the high incidence of metabolic diseases. The lifestyle during postnatal development can result in altered metabolic programming, thereby impairing the reproductive system and fertility during adulthood. Therefore, the aim of this study was to evaluate the effect of a high-fructose diet in the male reproductive system of pubertal and adult rats. Male Wistar rats (30 d old) were assigned to four different groups: Fr30, which received fructose (20%) in water for 30 d and were euthanized at postnatal day (PND) 60; Re-Fr30, which received fructose (20%) for 30 d and were euthanized at PND 120; and two control groups C30 and Re-C30, which received water ad libitum and were euthanized at PND 60 and 120, respectively. Fructose induced an increase in abnormal seminiferous tubules with epithelial vacuoles, degeneration, and immature cells in the lumen. Moreover, Fr30 rats showed altered spermatogenesis and daily sperm production (DSP), as well as increased serum testosterone concentrations. After discontinuing high-fructose consumption, DSP and sperm number decreased significantly. We observed tissue remodeling in the epididymis, with a reduction in stromal and epithelial compartments that might have influenced sperm motility. Therefore, we concluded that fructose intake in peripubertal rats led to changes in the reproductive system observed both during puberty and adulthood.

The essential role of intraflagellar transport protein IFT81 in male mice spermiogenesis and fertility.

Intraflagellar transport (IFT) is an evolutionarily conserved mechanism that is indispensable for the formation and maintenance of cilia and flagella; however, the implications and functions of IFT81 remain unknown. In this study, we disrupted IFT81 expression in male germ cells starting from the spermatocyte stage. As a result, homozygous mutant males were completely infertile and displayed abnormal sperm parameters. In addition to oligozoospermia, spermatozoa presented dysmorphic and nonfunctional flagella. Histological examination of testes from homozygous mutant mice revealed abnormal spermiogenesis associated with sloughing of germ cells and the presence of numerous multinucleated giant germ cells (symblasts) in the lumen of seminiferous tubules and epididymis. Moreover, only few elongated spermatids and spermatozoa were seen in analyzed cross sections. Transmission electron microscopy showed a complete disorganization of the axoneme and para-axonemal structures such as the mitochondrial sheath, fibrous sheath, and outer dense fibers. In addition, numerous vesicles that contain unassembled microtubules were observed within developing spermatids. Acrosome structure analysis showed normal appearance, thus excluding a crucial role of IFT81 in acrosome biogenesis. These observations showed that IFT81 is an important member of the IFT process during spermatogenesis and that its absence is associated with abnormal flagellum formation leading to male infertility. The expression levels of several IFT components in testes, including IFT20, IFT25, IFT27, IFT57, IFT74, and IFT88, but not IFT140, were significantly reduced in homozygous mutant mice. Overall, our study demonstrates that IFT81 plays an essential role during spermatogenesis by modulating the assembly and elongation of the sperm flagella.

Chronic sleep loss disrupts blood-testis and blood-epididymis barriers, and reduces male fertility.

Sleep loss increases blood-brain barrier permeability. As the blood-brain barrier and the blood-tissue barriers in the reproductive tract (blood-testis and blood-epididymis barriers) share common characteristics, we hypothesized that sleep restriction may also modify their barrier function. Previous reports showed that sleep loss decreased sperm viability and progressive fast mobility, which may be a consequence of altered blood-testis and blood-epididymis barrier. Therefore, we quantified changes in blood-testis and blood-epididymis barrier after sleep loss and related them to male fertility. Adult male Wistar rats were sleep restricted using the multiple-platform technique in a protocol of 20 hr daily sleep deprivation plus 4 hr of sleep recovery in the home-cage. At the 10th day, barrier permeability assays were performed with Na-fluorescein, 10 kDa Cascade blue-dextrans and Evans blue, and the expression of tight junction proteins, actin and androgen receptor was quantified. At the 10th day of sleep restriction and after sleep recovery days 1-7, males were placed with sexually receptive females, sexual behaviour was tested, and the percentage of pregnancies was calculated. Sleep restriction increased the barrier permeability to low- and high-molecular-weight tracers, and decreased the expression of tight junction proteins, actin and androgen receptor. Concomitantly, sleep restriction reduced the percentage of ejaculating males and the number of pregnancies. Sleep recovery for 2-3 days progressively re-established fertility, as indicated by a higher percentage of ejaculating males and impregnated females. In conclusion, chronic sleep loss alters fertility concomitantly with the disruption of the blood-tissue barriers at the reproductive tract, the mechanism involves androgen signalling.

Taurine Increases Spermatozoa Quality and Function in Asthenospermia Rats Impaired by Ornidazole.

Asthenospermia has been considered as one of the crucial causes of male infertility, which was closely related to epididymal dysfunction. Lots of documents have revealed that taurine palys an important role in male reproduction, including antioxidation, membrane stabilization, stimulation of sexual hormone secretion and elevation of sperm quality. The objective of this study was to expose the effect of taurine on spermatozoa quality and function in ornidazole-induced asthenospermia rats. We found that taurine treatment could obviously recover the decline of cauda epididymal sperm count, viability and motility, and the elevation of sperm abnormality in asthenospermia animals. Spermatozoa acrosin, LDH-X, SDH and CCO activities of model rats also were notably increased by taurine administration. The present data indicated that taurine could raise spermatozoa quality and function by elevating mitochondrial energy metabolism. Notably, taurine supplementation markedly raised serum GnRH, LH and T levels in asthenospermia rays, suggesting taurine rescued asthenosperm by means of stimulating hypothalamic-pituitary-testicular axis secretion. We also found that concentrations of asthenospermia epididymal carnitine, SA, α-Glu and ACP, and mRNA expression levels of MMP7 and IDO2 were significantly rised by taurine administration, indicating taurine may protect epididymal epithelium structure, improve secretion activity, and maintain intraluminal microenvironment homeostasis. Finally, the present results showed taurine effectively increased cauda epididymal SOD, GSH and γ-GT levels in model rats, reduced ROS and MDA production, suggesting epididymal antioxidant ability of asthenospermia rats could be elevated by taurine treatment. To sum up, our results indicated that taurine can promote spermatozoa quality and function in ornidazole-induced asthenospermia rats by facilitating epididymal epithelium secretion and luminal microenvironment homeostasis.

Spermatogenesis disorder caused by T-2 toxin is associated with germ cell apoptosis mediated by oxidative stress.

T-2 toxin is an unavoidable contaminant in human food, animal feeds, and agricultural products. T-2 toxin has been found to impair male reproductive function. But, few data is available that reveals the reproductive toxicity mechanism. In the study, male Kunming mice were orally administrated with T-2 toxin at the doses of 0, 0.5, 1 or 2 mg/kg body weight for 28 days. The body and reproductive organs weight, the concentration, malformation rate and ultrastructure of sperm in cauda epididymis were detected. Oxidative stress biomarkers and apoptosis were also measured in testes. Histological change of testes was performed by H&E and TUNEL staining. T-2 toxin down-regulated body and reproductive organs (testis, epididymis and seminal vesicle) weight, sperm concentration, increased sperm malformation rate and damaged the ultrastructure of sperm and structure of testes. T-2 toxin treatment increased the reactive oxygen species (ROS) and malondialdehyde content, while, decreased the total anti-oxidation capacity (T-AOC) and the superoxide dismutase activity in testes. T-2 toxin exposure increased the TUNEL-positive germ cells, the activities and mRNA expressions of caspase-3, caspase-8 and caspase-9, the mRNA expression of Bax, and inhibited the Bcl-2 mRNA expression. Furthermore, the expressions of caspase-3, caspase-8 caspase-9 and Bax were positively correlated with ROS level, but negatively correlated with T-AOC in testis. In summary, T-2 toxin caused spermatogenesis disorder associated with the germ cell apoptosis medicated by oxidative stress, impairing the male reproductive function.

Prospective analysis of factors predicting feasibility & success of longitudinal intussusception vasoepididymostomy in men with idiopathic obstructive azoospermia.

BACKGROUND & OBJECTIVES: : Microsurgical reconstruction for idiopathic obstructive azoospermia is a challenging procedure, and selection of appropriate patients is important for successful outcomes. This prospective study was done to evaluate the ability of scrotal ultrasound measurements to predict the surgical feasibility and determine factors that could predict a patent anastomosis following vaso-epididymal anastomosis (VE) in men with idiopathic obstructive azoospermia. METHODS: : In this prospective study, men diagnosed with idiopathic obstructive azoospermia, scheduled for a longitudinal intussusception VE, underwent a scrotal ultrasound measurement of testicular and epididymal dimensions. During surgery, site and type of anastomosis, presence of sperms in the epididymal fluid and technical satisfaction with the anastomosis were recorded. All men where VE could be performed were followed up for appearance of sperms in the ejaculate. Ultrasound parameters were compared between men who had a VE versus those with negative exploration. Predictive factors were compared between men with or without a patent anastomosis. RESULTS: : Thirty four patients were included in the study conducted between September 2014 and August 2016 and a VE was possible in only 19 (55%) patients. Of these 19 patients, six had a patent anastomosis with one pregnancy. Preoperative ultrasound measurements could not identify patients where a VE could not be performed. Motile sperm in the epididymal fluid was the only significant predictor of a successful anastomosis. INTERPRETATION & CONCLUSION: : Forty five per cent of men planned for a VE for idiopathic obstructive azoospermia could not undergo a reconstruction. Ultrasound assessment of testicular and epididymal dimensions could not predict the feasibility of performing a VE. The presence of motile sperms in the epididymal fluid was the only significant predictor of a patent VE in our study.

Lack of androgen receptor SUMOylation results in male infertility due to epididymal dysfunction.

Androgen receptor (AR) is regulated by SUMOylation at its transactivation domain. In vitro, the SUMOylation is linked to transcriptional repression and/or target gene-selective regulation. Here, we generated a mouse model (ArKI) in which the conserved SUMO acceptor lysines of AR are permanently abolished (ArK381R, K500R). ArKI males develop normally, without apparent defects in their systemic androgen action in reproductive tissues. However, the ArKI males are infertile. Their spermatogenesis appears unaffected, but their epididymal sperm maturation is defective, shown by severely compromised motility and fertilization capacity of the sperm. Fittingly, their epididymal AR chromatin-binding and gene expression associated with sperm maturation and function are misregulated. AR is SUMOylated in the wild-type epididymis but not in the testis, which could explain the tissue-specific response to the lack of AR SUMOylation. Our studies thus indicate that epididymal AR SUMOylation is essential for the post-testicular sperm maturation and normal reproductive capability of male mice.

Experimental exposure to gasohol impairs sperm quality with recognition of the classification pattern of exposure groups by machine learning algorithms.

Contamination caused by leakage at gas stations leads to possible exposure of the general population when in contact with contaminated water and soil. The present study aimed to evaluate the reproductive effects of exposure of adult male rats to gasohol and evaluate the performance of machine learning (ML) algorithms for pattern recognition and classification of the exposure groups. Rats were orally exposed to 0 (control), 16 (EA), 160 (EB), or 800 mg kg-1 bw day-1 of gasohol (EC), for 30 consecutive days. Sperm quality of the groups exposed to two higher doses was reduced in comparison to the control group. The sperm parameters decreased were: daily sperm production, sperm number in the caput/corpus epididymis, progressive motility, mitochondrial activity, and acrosomal membrane integrity. Sperm transit time in the epididymis cauda and sperm isolated head were increased in EB and EC. Sertoli cells number was decreased in these groups, but their support capacity was maintained. ML methods were used to identify patterns between samples of control and exposure groups. The results obtained by ML methods were very promising, obtaining about 90% of accuracy. It was concluded that the exposure of rats to different doses of gasohol impair spermatogenesis and sperm quality, with a recognizable classification pattern of exposure groups at ML.

[Oxidative stress induces damage to epididymal epithelial tight junction protein ZO-1 and impairs epididymal function in varicocele rats].

OBJECTIVE: To investigate oxidative stress-mediated damage to the epididymal epithelial tight junction protein ZO-1 and its impact on epididymal function in varicocele rats. METHODS: We randomly divided 45 male adolescent SD rats into three groups of equal number: sham operation (left renal vein exposed and isolated), experimental (left renal vein constricted and collaterals of the left spermatic vein fully ligated), and treatment (60-day intragastric administration of vitamin E at 150 mg/kg/d after modeling). At 60 days after modeling, we observed the histological changes in the left epididymis, detected the expressions of ZO-1 and other tight junction-related proteins by real-time quantitative PCR, immunohistochemistry, immunofluorescence staining and Western blotting, determined sperm motility, and measured the levels of superoxide dismutase (SOD), total antioxidant capacity (T-AOC), methylene dioxyamphetamine (MDA) and α-glucosidase (α-Glu) in the epididymal tissue of the rats. RESULTS: Compared with the rats of the sham operation group, those of the experimental group showed disorganized epithelial structure and decreased number of epithelial cells in the left epididymis, with some epithelial cells desquamated into the lumen. The expression of ZO-1 was significantly lower in the experimental than in the sham operation group (P < 0.05) but markedly upregulated after VE treatment (P < 0.05). In comparison with the sham operation group, the animals in the experimental group exhibited remarkably increased content of MDA in the epididymal tissue (ï¼»0.41 ± 0.05ï¼½ vs ï¼»1.21 ± 0.18ï¼½ nmol/mg prot, P < 0.05) but decreased levels of SOD (ï¼»814.65 ± 73.64ï¼½ vs ï¼»298.62 ± 67.84ï¼½ U/mg prot, P < 0.05), T-AOC (ï¼»0.84 ± 0.07ï¼½ vs ï¼»0.24 ± 0.04ï¼½ nmol/mg prot, P < 0.05) and α-Glu (ï¼»11.72 ± 2.72ï¼½ vs ï¼»5.82 ± 1.24ï¼½ U/mg prot, P < 0.05). VE treatment, however, remarkably reduced the content of MDA (ï¼»0.69 ± 0.12ï¼½ nmol/mg prot) and elevated the levels of SOD (ï¼»497.73 ± 48.03ï¼½ U/mg prot), T-AOC (ï¼»0.42 ± 0.06ï¼½ nmol/mg prot) and α-Glu (ï¼»9.11 ± 1.91ï¼½ U/mg prot) as compared with those in the experimental group (all P < 0.05). The percentage of progressively motile sperm was significantly lower in the experimental than in the sham operation group (ï¼»31.33 ± 6.32ï¼½% vs ï¼»71.21 ± 5.21ï¼½%, P < 0.05), but markedly increased after VE treatment (ï¼»60.68 ± 5.31ï¼½%, P < 0.05). CONCLUSIONS: Varicocele reduces the expression of the EETJ protein ZO-1 and impairs epididymal function via oxidative stress, while vitamin E can effectively upregulate the ZO-1 expression and improve epididymal function by decreasing oxidative stress in the epididymis of varicocele rats.

[Impact of subchronic exposure to low-dose nano-nickel oxide on the reproductive function and offspring of male rats].

OBJECTIVE: To investigate the influence of subchronic exposure to low-dose subchronic nano-nickel oxide (NNO) on the reproductive function of male rats and embryonic development of the pregnant rats. METHODS: Fifty normal healthy male SD rats weighing 180－220 g were randomly divided into five groups of equal number, negative control, 4 mg/ml micro-nickel oxide (MNO), and 0.16, 0.8 and 4 mg/ml NNO, those of the latter four groups exposed to MNO or NNO by non-contact intratracheal instillation once every 3 days for 60 days, and then all mated with normal adult female rats in the ratio of 1∶2. After the female animals were confirmed to be pregnant, the males were sacrificed and the weights of the body, testis and epididymis obtained, followed by calculation of the visceral coefficients, determination of epididymal sperm concentration and viability and the nickel contents in the blood and semen by atomic fluorescence spectrometry. The female rats were killed on the 20th day of gestation for counting of the implanted fertilized eggs and live, dead and resorbed fetuses. RESULTS: After 60 days of exposure, the rats of the NNO groups showed no statistically significant differences from those of the negative control and MNO groups in the weights of the body, testis and epididymis or visceral coefficients. Compared with the negative control group, the animals of the 0.8 and 4 mg/ml NNO groups exhibited markedly decreased sperm concentration (ï¼»9.36 ± 0.98ï¼½ vs ï¼»7.49 ± 1.46ï¼½ and ï¼»6.30 ± 1.36ï¼½ ×106/ml, P < 0.05) and viable sperm (ï¼»85.35 ± 9.16ï¼½% vs ï¼»68.26 ± 16.63ï¼½% and ï¼»65.88 ± 14.68ï¼½ %, P < 0.05), increased morphologically abnormal sperm (ï¼»8.30 ± 2.47ï¼½% vs ï¼»13.99 ± 4.87ï¼½% and ï¼»15.38 ± 8.86ï¼½ %, P < 0.05), and elevated rate of dead and resorbed fetuses (1.18% vs 6.89% and 7.37%, P < 0.05), blood nickel content (ï¼»0.13 ± 0.16ï¼½ vs ï¼»0.52 ± 0.34ï¼½ and ï¼»0.82 ± 0.44ï¼½ mg/L, P < 0.05) and semen nickel content (ï¼»0.08 ± 0.13ï¼½ vs ï¼»0.35 ± 0.23ï¼½ and ï¼»0.63 ± 0.61ï¼½ mg/L, P < 0.05). The nickel level in the semen was correlated significantly with that in the blood (r = 0.912, P <0.01), negatively with the rate of viable sperm (r = －0.879, P <0.01) and positively with the percentage of morphologically abnormal sperm (r = －0.898, P <0.01). CONCLUSIONS: Sixty-day exposure to nano-nickel oxide at 0.8 and 4 mg/ml can produce reproductive toxicity in male rats and result in fetal abnormality in the females, while that at 0.16 mg/ml has no significant toxic effect on the reproductive function of the males.

Slc26a3 deficiency is associated with epididymis dysplasia and impaired sperm fertilization potential in the mouse.

Members of the solute carrier 26 (SLC26) family have emerged as important players in mediating anions fluxes across the plasma membrane of epithelial cells, in cooperation with the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. Among them, SLC26A3 acts as a chloride/bicarbonate exchanger, highly expressed in the gastrointestinal, pancreatic and renal tissues. In humans, mutations in the SLC26A3 gene were shown to induce congenital chloride-losing diarrhea (CLD), a rare autosomal recessive disorder characterized by life-long secretory diarrhea. In view of some reports indicating subfertility in some male CLD patients together with SLC26-A3 and -A6 expression in the male genital tract and sperm cells, we analyzed the male reproductive parameters and functions of SLC26A3 deficient mice, which were previously reported to display CLD gastro-intestinal features. We show that in contrast to Slc26a6, deletion of Slc26a3 is associated with severe lesions and abnormal cytoarchitecture of the epididymis, together with sperm quantitative, morphological and functional defects, which altogether compromised male fertility. Overall, our work provides new insight into the pathophysiological mechanisms that may alter the reproductive functions and lead to male subfertility in CLD patients, with a phenotype reminiscent of that induced by CFTR deficiency in the male genital tract.

Epididymal more than testicular abnormalities are associated with the occurrence of antisperm antibodies as evaluated by the MAR test.

STUDY QUESTION: Is there any association between mixed antiglobulin reaction (MAR) test positivity and clinical features or genital tract ultrasound (US) parameter values in males of infertile and fertile couples? STUDY ANSWER: In males of infertile and fertile couples MAR test positivity was associated with clinical and US features suggestive of chronic epididymal inflammation. WHAT IS KNOWN ALREADY: MAR test positivity has been more often reported in males of infertile couples than in fertile men. A positive MAR test has been detected in men with a history of testicular or post-testicular damage. No previous study has reported US alterations related to MAR test positivity. This is the first study that has systematically evaluated associations between a positive MAR test and clinical, seminal and US characteristics of the entire male genital tract. STUDY DESIGN, SIZE, DURATION: This cross-sectional analysis included 109 fertile men and 699 consecutive subjects seeking medical care for couple infertility from September 2012 to September 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: All subjects underwent, in our outpatient clinic, a complete physical, endocrine, scrotal and transrectal US evaluation and semen analysis (including sIL-8) on the same day. Of the 699 males of infertile couples, 181 (age 38.6 ± 6.6 years) had an assessable MAR test, whereas the test was assessable in all 109 fertile men (age 36.6 ± 5.2 years). The associations among MAR test positivity and the other studied parameters were investigated on a caseload of 290 men (patients + fertile men) and in the two cohorts of males of infertile and fertile couples. MAIN RESULTS AND THE ROLE OF CHANCE: Of the 181 men of infertile couples studied, 20 (11%) had a positive MAR test, including 12 (6.6%) who had a MAR test ≥ 50%, which is considered as a pathological threshold according to the WHO. Of the 109 fertile men, four (3.7%) had a positive MAR test, of which one (0.9%) had a MAR test ≥ 50%. MAR test positivity was therefore found more often in men of infertile couples (P < 0.05). In the entire caseload (n = 290) of males of both infertile and fertile couples, no correlations between MAR test positivity and seminal characteristics were observed. A positive MAR test was associated with epididymal US abnormalities, particularly with the mean size of the epididymal body and tail (both P < 0.0001), and in infertile men, a positive MAR test was also associated with an abnormal epididymal echotexture. In addition, subjects with a positive MAR test more frequently showed a history of epididymitis and high sIL-8 levels. Considering endocrine parameters, only a positive correlation between MAR test positivity and LH levels was observed, even after adjusting for age and life-style factors (adj. r = 0.232, P < 0.0001), while no associations with testosterone and FSH levels were found. LIMITATIONS, REASONS FOR CAUTION: Antisperm antibodies (ASA) were detected in this study by using the SpermMAR test IgG, but other tests are available. In addition, for technical reasons, the MAR test is not assessable in subjects with severe oligo-astheno-zoospermia and, therefore, this test may lead to an intrinsic selection bias. Finally, owing to the cross-sectional nature of the study, neither a causality hypothesis nor mechanistic models can be inferred. WIDER IMPLICATIONS OF THE FINDINGS: First, our results indicate that MAR test positivity is associated with clinical and US signs suggestive of chronic epididymal inflammation and not testicular damage. Hence, when investigating a subject with a positive MAR test, the epididymis and not just the testis should be evaluated. Furthermore, MAR test positivity was more often detected in males of infertile couples than in fertile men, but it was not associated with conventional semen parameter values. Our data support a role of ASA in couple infertility, regardless of the conventional sperm analysis. How ASA affects couple fertility needs to be addressed by further studies. STUDY FUNDING/COMPETING INTEREST(S): Grants were received from the Ministry of University and Scientific Research (SIR project to F.L., protocol number: RBSI14LFMQ). There are no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Case Report: Filaria or Megasperm? A Cause of an Ultrasonographic "Filarial Dance Sign".

Bancroftian filariasis can cause genital abnormalities related to chronic inflammation and obstruction of the afferent lymphatic vessels, and may demonstrate a "filarial dance sign" on scrotal ultrasound with mobile echogenic particles observed. We present a patient with a positive "filarial dance sign," travel within Latin America, and negative filarial serology.

Alteration of transporter activities in the epididymides of infertile initial segment-specific Pten knockout mice.

A fully functional initial segment, the most proximal region of the epididymis, is important for male fertility. Our previous study generated a mouse model to investigate the importance of initial segment function in male fertility. In that model, phosphatase and tensin homolog (Pten) was conditionally removed from the initial segment epithelium, which resulted in epithelial de-differentiation. When spermatozoa progressed through the de-differentiated epithelial duct, they developed angled flagella, suggesting compromised sperm maturation, which eventually resulted in male infertility. To understand the molecular mechanisms, by which PTEN regulates epididymal sperm maturation, we compared the transcriptome profile of the initial segment between controls and initial segment-specific Pten knockouts and revealed that water, ion, and organic solute transporter activities were one of the top molecular and cellular functions altered following loss of Pten. Alteration in protein levels and localization of several transporters following loss of Pten were also observed by immunofluorescence analysis. Epithelial cells of the initial segment from knockouts were more permeable to fluorescein isothiocyanate-dextran (4000 Da) compared to controls. Interestingly, conditional deletion of Pten from other organs also resulted in changes in transporter activity, suggesting a common role of PTEN in regulation of transporter activity. Taken together, our data support the hypothesis that loss of Pten from the initial segment epithelium results in changes in the transporting and permeability characteristics of the epithelium, which in turn altered the luminal fluid microenvironment that is so important for sperm maturation and male fertility.

SLC9A3 Protein Is Critical for Acrosomal Formation in Postmeiotic Male Germ Cells.

Solute carrier family 9 isoform 3 (SLC9A3), a Na⁺/H⁺ exchanger, regulates the transepithelial absorption of Na⁺ and water and is primarily expressed on the apical membranes of the intestinal epithelium, renal proximal tubule, epididymis, and vas deferens. Loss of the Slc9a3 allele in mice enhances intestinal fluid and causes diarrhoea as a consequence of diminished Na⁺ and HCO3- absorption. Hence, the loss also causes male infertility and reveals the abnormal dilated lumen of the rete testis and calcification in efferent ductules. However, whether loss of Slc9a3 alleles also disrupts mammalian spermatogenesis remains unknown. First, through immunoblotting, we determined that SLC9A3 is highly expressed in the murine testis compared with the small intestine, epididymis, and vas deferens. During murine spermatogenesis, SLC9A3 is specifically expressed in the acrosome region of round, elongating, and elongated spermatids through immunostaining. Furthermore, SLC9A3 signals are enriched in the acrosome of mature sperm isolated from the vas deferens. In Slc9a3 knockout (KO) mice, compared with the same-aged controls, the number of spermatids on the testicular section of the mice progressively worsened in mice aged 20, 35, and 60 days. Sperm isolated from the epididymis of Slc9a3 KO mice revealed severe acrosomal defects. Our data indicated that SLC9A3 has a vital role in acrosomal formation during spermiogenesis.

Sleep restriction in Wistar rats impairs epididymal postnatal development and sperm motility in association with oxidative stress.

Good sleep quality has a direct effect on the activity of the neuroendocrine-reproductive control axis and oxidative stress. Thus, the aim of the present study was to evaluate whether sleep restriction (SR) during the peripubertal period impaired the postnatal development of the epididymis in Wistar rats. After 21 days SR (18h per day), epididymides were collected on Postnatal Day (PND) 62 for evaluation of oxidative stress markers, inflammatory profile, sperm count and histopathological and stereological analyses; in addition, the motility of spermatozoa from the vas deferens was examined. SR significantly increased lipid peroxidation and glutathione levels in the caput and cauda epididymidis, and increased levels of total radical-trapping antioxidant potential in the caput epididymidis only. Neutrophil migration to the caput or corpus epididymidis was decreased by SR, and the size of the luminal compartment in the 2A region and the epithelial compartment in the 5A/B region was also decreased. In these regions, there was an increase in the size of the interstitial compartment. The percentage of immotile spermatozoa was higher in the SR group. In conclusion, SR affects epididymal postnatal development, as well as sperm motility, in association with increased oxidative stress and a decrease in the size of the epithelial compartment in the cauda epididymidis.

Spermaurin, an La1-like peptide from the venom of the scorpion Scorpio maurus palmatus, improves sperm motility and fertilization in different mammalian species.

STUDY QUESTION: Is it possible to identify original compounds that are able to enhance sperm motility from the venom of the scorpion Scorpio maurus palmatus? SUMMARY ANSWER: We identified a potent disulfide-rich peptide (DRP) of 73 amino acids that significantly improved the motility of fresh and frozen-thawed sperm in different mammalian species, including human, and improved fertilization outcome in mouse IVF experiments. WHAT IS KNOWN ALREADY: Any disturbance of sperm motility has a strong impact on fertilization and can lead to subfertility or infertility. Significant efforts have, therefore,  been made to identify pharmacological drugs that might improve sperm motility. Such compounds are particularly useful in azoospermia to improve testicular sperm extraction and in the domain of cryopreservation because the motility of frozen-thawed sperm is reduced. STUDY DESIGN, SIZE, DURATION: This was a basic science/medical research study aimed at identifying original compounds from a library of venoms able to enhance mammalian sperm motility, including human. We first identified in the venom of a scorpion S. m. palmatus a fraction able to potently activate sperm motility. We next purified and characterized the compound by liquid chromatography, mass spectrometry and peptide synthesis. Finally, the potency and toxicity of both purified and synthetic versions of the identified compound on sperm motility were assessed using different in vitro tests in different mammalian species. PARTICIPANTS/MATERIALS, SETTING, METHODS: For human sperm, biological samples were collected from normozoospermic donors and subfertile patients attending a reproduction department for diagnostic semen analysis. Testicular sperm was collected from cynomolgus monkeys (Macaca fascicularis) euthanized for the needs of specific authorized research projects. The peptide was also tested on bovine and mouse epidydimal sperm. We measured different sperm motility parameters with a computer-assisted sperm analysis system in the presence or absence of the peptide. MAIN RESULTS AND THE ROLE OF CHANCE: Size exclusion chromatography enabled us to isolate a fraction of the venom of S. m. palmatus able to increase sperm motility. By liquid chromatography and mass spectrometry, a peptide comprising 73 amino acids with 4 disulfide bridges was identified as responsible for the biological activity and called 'spermaurin'. The identity of spermaurin was confirmed by chemical synthesis. We showed that the peptide increased the motility of fresh and frozen-thawed human sperm. We observed that the potency of the peptide was higher on fresh ejaculated spermatozoa with a low motility, achieving a 100% increase of curvilinear velocity in poorly performing sperm. We also demonstrated that peptide is effective on bovine and mouse fresh epididymal, bovine frozen-thawed ejaculated and fresh non-human primate testicular sperm. Finally, in mouse IVF, the production of 2-cell embryos was increased by 24% when sperm were treated with the peptide. LIMITATIONS, REASONS FOR CAUTION: This work is an in vitro evaluation of the ability of spermaurin to improve sperm motility parameters. Another limitation of this study is the small number of human sperm samples tested with the natural (n = 36) and synthetic (n = 12) peptides. Moreover, the effect of the peptide on IVF outcome was only tested in mouse and further tests with human and bovine gametes are required to confirm and extend this result in other mammalian species. WIDER IMPLICATIONS OF THE FINDINGS: This work confirms our initial study showing that venoms represent an interesting source of molecules that are able to modify sperm physiology. Moreover, this work presents the first demonstrated biological action of a venom peptide from the scorpion S. m. palmatus with sequence similarities to La1 peptide from Liocheles australasiae (Wood scorpion), a widespread family of DRPs. LARGE SCALE DATA: Not applicable. STUDY FUNDING/COMPETING INTEREST(S): This work is part of the project 'LAB COM-14 LAB7 0004 01-LIPAV', funded by the program LabCom 2014 from the French Research Agency (ANR). Dr Arnoult reports grants from IMV Technologies during the conduct of the study. In addition, Drs Arnoult, Martinez, Ray and Schmitt have a patent EP16305642.7 pending containing some of the information presented in this manuscript.

The Effects of l-Carnitine Against Cyclophosphamide-Induced Injuries in Mouse Testis.

In order to explore the possibility of l-carnitine (LC) as a protector of male fertility in chemotherapy, we observed the damage of cyclophosphamide (CTX) to Sertoli cells and the protective effect of LC on the testis Sertoli cells from such damage in this study. Healthy adult male mice were divided into three groups: chemotherapy group were injected intraperitoneally with the CTX; protective agent group were injected both LC and CTX; control group mice were injected only with isochoric physiological saline; all once a day for 5 days. After 5 days, the mice were, respectively, killed at 24 hr after the last injection. The testis and epididymis were removed. Epididymis was for sperm analysis immediately, and immunohistochemistry, RT-PCR and Western blot for the assessments of occludin, glial cell-derived neurotrophic factor (GDNF) and TGF-ß3 mRNA and protein expression. The sperm analysis of epididymis showed that CTX can significantly decrease sperm count and motility; and administration of LC resulted in significant recovery of the sperm count and sperm motility. Compared with control group, the expressions of occludin and GDNF decreased and the expression of TGF-ß3 increased significantly (p < 0.05) in the CTX group. In the LC + CTX group, the expressions of occludin and GDNF were higher than those of the CTX group and similar to those of the control group; the TGF-ß3 expression was lower (p < 0.05) than that of the CTX group and similar to that of the control group. The results of this study showed that CTX could damage the spermatogenesis and reduce the expression of occludin and GDNF, and increase the expression of TGF-ß3 in testis of mouse, which indicates CTX's damage or efficacy to testis Sertoli cells. LC could protect the Sertoli cells of testis from these damages caused by CTX, and promote or protect the spermatogenesis. In conclusion, this study provides meaningful information about the possible damage to male fertility by chemotherapeutics and potential of LC in the protection of male fertility during chemotherapy.

Relationship between Undescended Testis Position and Prevalence of Testicular Appendices, Epididymal Anomalies, and Patency of Processus Vaginalis.

OBJECTIVES: To assess the incidence of testicular appendices (Tas), epididymal anomalies (EAs), and processus vaginalis (PV) patency in patients with undescended testis (UT) according to testicular position and to compare them with human fetuses. METHODS: We studied 85 patients (108 testes) with cryptorchidism and compared the features with those of 15 fetuses (30 testes) with scrotal testes. We analyzed the relationships among the testis and epididymis, patency of PV, and the presence of TAs. We used the Chi-square test for statistical analysis (p < 0.05). RESULTS: In 108 UT, 72 (66.66%) had PV patent, 67 (62.03%) had TAs, and 39 (36.12%) had EAs. Of the 108 UT, 14 were abdominal (12.96%; 14 had PV patency, 9 TAs, and 7 EAs); 81 were inguinal (75%; 52 had PV patency, 45 TAs, and 31 EAs), and 13 were suprascrotal (12.03%; 6 had PV patency, 13 TAs, and 1 EAs). The patency of PV was more frequently associated with EAs (p = 0.00364). The EAs had a higher prevalence in UT compared with fetuses (p = 0.0005). CONCLUSIONS: Undescended testis has a higher risk of anatomical anomalies and the testes situated in abdomen and inguinal canal have a higher risk of presenting patency of PV and EAs.