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.

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.

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.

[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.

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.

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.

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.

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.

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.

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.

Imbalanced lipid homeostasis in the conditional Dicer1 knockout mouse epididymis causes instability of the sperm membrane.

During epididymal sperm maturation, the lipid content of the sperm membrane is modified, which facilitates sperm motility and fertility. However, little is known about the mechanisms regulating the maturation process. By generating a conditional knockout (cKO) of Dicer1 in the proximal part of the mouse epididymis, we studied the role of RNA interference in epididymal functions. The Dicer1 cKO epididymis displayed an altered lipid homeostasis associated with a 0.6-fold reduction in the expression of the gene elongation of very long chain fatty acids-like 2, an enzyme needed for production of long-chain polyunsaturated fatty acids (PUFAs). Furthermore, the expression of several factors involved in cholesterol synthesis was up-regulated. Accordingly, the Dicer1 cKO sperm membrane showed a 0.7-fold decrease in long-chain PUFAs, whereas the amount of cholesterol in acrosome-reacted sperm displayed a 1.7-fold increase. The increased cholesterol:PUFA ratio of the sperm membrane caused breakage of the neck and acrosome region and immotility of sperm. Dicer1 cKO mice sperm also displayed reduced ability to bind to and fertilize the oocyte in vitro. This study thus shows that Dicer1 is critical for lipid synthesis in the epididymis, which directly affects sperm membrane integrity and male fertility.

Heat-killed Lactobacillus Reuteri GMNL-263 Prevents Epididymal Fat Accumulation and Cardiac Injury in High-Calorie Diet-Fed Rats.

High-calorie diet-induced obesity leads to cardiomyocyte dysfunction and apoptosis. Impaired regulation of epididymal fat content in obese patients has been known to increase the risk of cardiac injury. In our study, a lactic acid bacteria, Lactobacillus reuteri GMNL-263, was evaluated for its potential to reduce body weight and body fat ratio and to prevent heart injury in rats with high-fat diet-induced obesity. Lactic acid bacteria supplementation restored the cardiac function and decreased the physiological changes in the heart of the obese rats. In addition, the Fas/Fas-associated protein pathway-induced caspase 3/e Poly polymerase mediated apoptosis in the cardiomyocytes of the obese rats was reversed in the Lr263-treated rats. These results reveal that fed with Lr-263 reduces body fat ratio, inhibits caspase 3-mediated apoptosis and restores cardiac function in obese rats through recovery of ejection fraction and fractional shortening. Our results indicated that the administration of Lr263 lactic acid bacteria can significantly down-regulate body fat and prevent cardiomyocyte injury in obese rats.

Hypoxia-induced apoptosis and mechanism of epididymal dysfunction in rats with left-side varicocele.

To investigate the relationship between hypoxia and epididymal dysfunction and the mechanism of epididymal dysfunction in rats with left-side varicocele, a total of 45 male Wistar rats were randomly divided into three groups in average. The expression of hypoxia-inducible factor-1α (HIF-1α) was detected by Western blot and immunohistochemical analysis respectively. HIF-1α was expressed in the experimental group, and the positive rate was significantly higher than that of either the sham or the control group (P < 0.05). The apoptosis index (AI) of epididymal epithelium was higher in the experimental group (7.25 ± 2.56) than that in either the sham (0.52 ± 0.57, P < 0.01) or the control group (0.08 ± 0.13, P < 0.01). Additionally, the levels of sialic acid and carnitine were lower in the experimental group than that in either the sham or the control group (P < 0.05) and were significantly negatively correlated with HIF-1α expression (r = -0.620, P = 0.014, and r = -0.610, P = 0.016 respectively). It is concluded that left-side varicocele could cause epididymal hypoxia and epididymal dysfunction. Moreover, HIF-1α maybe act as useful factor to predict germ cell apoptosis in varicocele.

Nucleoside triphosphate diphosphohydrolase-1 ectonucleotidase is required for normal vas deferens contraction and male fertility through maintaining P2X1 receptor function.

In this work, we report that Entpd1(-/-) mice, deficient for the ectonucleotidase nucleoside triphosphate diphosphohydrolase-1 (NTPDase1), produce smaller litters (27% reduction) compared with wild-type C57BL6 animals. This deficit is linked to reduced in vivo oocyte fertilization by Entpd1(-/-) males (61 ± 11% versus 88 ± 7% for Entpd1(+/+)). Normal epididymal sperm count, spermatozoa morphology, capacitation, and motility and reduced ejaculated sperm number (2.4 ± 0.5 versus 3.7 ± 0.4 million for Entpd1(+/+)) pointed to vas deferens dysfunction. NTPDase1 was localized by immunofluorescence in the tunica muscularis of the vas deferens. Its absence resulted in a major ATP hydrolysis deficiency, as observed in situ by histochemistry and in primary smooth muscle cell cultures. In vitro, Entpd1(-/-) vas deferens displayed an exacerbated contraction to ATP, a diminished response to its non-hydrolysable analog αßMeATP, and a reduced contraction to electrical field stimulation, suggesting altered P2X1 receptor function with a propensity to desensitize. This functional alteration was accompanied by a 3-fold decrease in P2X1 protein expression in Entpd1(-/-) vas deferens with no variation in mRNA levels. Accordingly, exogenous nucleotidase activity was required to fully preserve P2X1 receptor activation by ATP in vitro. Our study demonstrates that NTPDase1 is required to maintain normal P2X1 receptor functionality in the vas deferens and that its absence leads to impaired peristalsis, reduced spermatozoa concentration in the semen, and, eventually, reduced fertility. This suggests that alteration of NTPDase1 activity affects ejaculation efficacy and male fertility. This work may contribute to unveil a cause of infertility and open new therapeutic potentials.

Bupropion treatment increases epididymal contractility and impairs sperm quality with no effects on the epididymal sperm transit time of male rats.

Bupropion is a dopamine (DA) and norepinephrine (NE) reuptake inhibitor used as smoking cessation and antidepressant drug with a lower incidence of male sexual dysfunction. We showed previously that sibutramine, a norepinephrine/serotonine reuptake inhibitor, reduced male rat fertility. As there are no studies evaluating the impact of bupropion treatment on spermatic parameters and male fertility, we evaluated the effects of bupropion treatment (15 and 30 mg kg(-1), 30 days) on sexual behavior, spermatic parameters and fertility of male Wistar rats and on the epididymal duct in vitro contractility. Bupropion 15 mg kg(-1) increased the serum luteinizing hormone level and the epididymal duct contractility, but the sperm quality was not affected. At 30 mg kg(-1) bupropion impaired sperm quality increasing the incidence of non-progressive sperm. The male sexual behavior and fertility were not modified at both bupropion doses. These results, in rats, suggest the importance of studies evaluating the effects of bupropion on the human male sperm quality.

Sonographic appearances of the epididymis in boys with acute testicular torsion but preserved testicular blood flow on color Doppler.

BACKGROUND: Little attention has been given to the sonographic appearances of the epididymis in testicular torsion. OBJECTIVE: To describe the position and morphology of the epididymis in childhood acute testicular torsion when testicular flow is present on color Doppler sonography. MATERIALS AND METHODS: We studied the sonographic findings in boys with clinically and surgically proven acute testicular torsion who were examined sonographically from May 2013 to May 2014 and who had preserved intratesticular flow on color Doppler sonography. We retrospectively evaluated the sonograms with emphasis on the epididymal findings. RESULTS: In all nine boys with confirmed torsion but with preserved intratesticular flow on color Doppler sonography, the epididymal head had an unexpected configuration and size, and no close relationship with the upper pole of the testis. In five of these children the spermatic cord appeared twisted on the affected side. In the remaining four boys the spermatic cord appeared straight. CONCLUSION: The position and morphology of the head of the epididymis were abnormal in all boys with acute testicular torsion but with preserved testicular flow.

A genome-wide analysis of open chromatin in human epididymis epithelial cells reveals candidate regulatory elements for genes coordinating epididymal function.

The epithelium lining the epididymis has a pivotal role in ensuring a luminal environment that can support normal sperm maturation. Many of the individual genes that encode proteins involved in establishing the epididymal luminal fluid are well characterized. They include ion channels, ion exchangers, transporters, and solute carriers. However, the molecular mechanisms that coordinate expression of these genes and modulate their activities in response to biological stimuli are less well understood. To identify cis-regulatory elements for genes expressed in human epididymis epithelial cells, we generated genome-wide maps of open chromatin by DNase-seq. This analysis identified 33,542 epididymis-selective DNase I hypersensitive sites (DHS), which were not evident in five cell types of different lineages. Identification of genes with epididymis-selective DHS at their promoters revealed gene pathways that are active in immature epididymis epithelial cells. These include processes correlating with epithelial function and also others with specific roles in the epididymis, including retinol metabolism and ascorbate and aldarate metabolism. Peaks of epididymis-selective chromatin were seen in the androgen receptor gene and the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which has a critical role in regulating ion transport across the epididymis epithelium. In silico prediction of transcription factor binding sites that were overrepresented in epididymis-selective DHS identified epithelial transcription factors, including ELF5 and ELF3, the androgen receptor, Pax2, and Sox9, as components of epididymis transcriptional networks. Active genes, which are targets of each transcription factor, reveal important biological processes in the epididymis epithelium.

Vitamin A deprivation affects the progression of the spermatogenic wave and initial formation of the blood-testis barrier, resulting in irreversible testicular degeneration in mice.

The blood testis-barrier (BTB) is essential for maintaining homeostasis in the seminiferous epithelium. Although many studies have reported that vitamin A (VA) is required for the maintenance of spermatogenesis, the relationships between the BTB, spermatogenesis and VA have not been elucidated. In this study, we analyzed BTB assembly and spermatogenesis in the testes of mice fed the VA-deficient (VAD) diet from the prepubertal period to adulthood. During the prepubertal period, no changes were observed in the initiation and progression of the first spermatogenic wave in mice fed the VAD diet. However, the numbers of preleptotene/leptotene spermatocytes derived from the second spermatogenic wave onwards were decreased, and initial BTB formation was also delayed, as evidenced by the decreased expression of mRNAs encoding BTB components and VA signaling molecules. From 60 days postpartum, mice fed the VAD diet exhibited apoptosis of germ cells, arrest of meiosis, disruption of the BTB, and dramatically decreased testis size. Furthermore, vacuolization and calcification were observed in the seminiferous epithelium of adult mice fed the VAD diet. Re-initiation of spermatogenesis by VA replenishment in adult mice fed the VAD diet rescued BTB assembly after when the second spermatogenic wave initiated from the arrested spermatogonia reached the preleptotene/leptotene spermatocytes. These results suggested that BTB integrity was regulated by VA metabolism with meiotic progression and that the impermeable BTB was required for persistent spermatogenesis rather than meiotic initiation. In conclusion, consumption of the VAD diet led to critical defects in spermatogenesis progression and altered the dynamics of BTB assembly.