Association between occupational testicular radiation exposure and lower male sex ratio of offspring among orthopedic surgeons.

BACKGROUND: Exposure to occupational radiation can lower the male sex ratio. However, specific radiation exposure to the testes has not been evaluated. OBJECTIVE: This study aimed to examine the association between testicular radiation exposure and lower male sex ratio in children. METHODS: A comprehensive questionnaire survey was administered to 62 full-time male doctors with children aged < 10 years at 5 hospitals. Based on the possibility of testicular radiation exposure 1 year before the child's birth, participants were assigned to 3 groups as follows: RT (orthopedic surgery), RNT (cardiology/neurosurgery), and N (others). Intergroup differences in the proportion of female children were ascertained, and the female sex ratio (number of female/total number) of each group was compared against the standard value of 0.486. Multivariate logistic regression analysis with a generalized estimating equation was used to model the effects on the probability of female birth while controlling for the correlation among the same fathers. RESULTS: The study population included 62 fathers and 109 children, 49 were female: 19/27, 11/30, and 19/52 in the RT, RNT, and N group, respectively; the RT group had the highest proportion of females (p = 0.009). The p values for comparisons with the standard sex ratio (0.486) were 0.02, 0.19, and 0.08 for the RT, RNT, and N groups, respectively. Based on the N group, the adjusted odds ratios for the child to be female were 4.40 (95% confidence interval 1.60-2.48) and 1.03 (0.40-2.61) for the RT and RNT groups, respectively. CONCLUSIONS: Our results imply an association between testicular radiation exposure and low male sex ratio of offspring. Confirmatory evidence is needed from larger studies which measure the pre-conceptional doses accumulated in various temporal periods, separating out spermatogonial and spermatid effects.

Valproic acid during pregnancy decrease the number of spermatogenic cells and testicular volume in the offspring of mice: Stereological quantification.

Valproic acid (VPA) is a drug used to treat epilepsy, bipolar disorders and headaches. As a secondary effect, this antiepileptic drug can cause a decrease in androgens and gonadotropins, and dose-dependent testicular defects, such as reduction of testicular weights, sperm motility and degeneration of the seminiferous tubules. In offspring exposed to VPA, its effects have not been evaluated, so the study aimed to determine the morphological effects of the use of VPA along testicular development in mice. 30 adult female BALB/c mice were crossed and divided by age, with embryos of 12.5 days post coitum (dpc), fetuses of 17.5 dpc and male mice 6 weeks postnatal. In each case, the pregnant mouse received 600 mg/kg of VPA, making up the VPA groups, or 0.3 mL of 0.9% physiological solution for the control groups, from the beginning to the end of the pregnancy, orally.t. A morpho-quantitative analysis was carried out on the gonadal development of the male offspring. In the groups treated with VPA, at all ages studied they had lower testicular volume. At 12.5 dpc, they showed less testicular development in the form of sex cords, with fewer gonocytes and somatic cells. At 17.5 dpc, they presented greater interstitial space, fewer spermatogonial, sustentacular Sertoli, peritubular and interstitial Leydig cells. At 6 weeks postnatal, they presented fewer spermatogonia, pachytene spermatocytes, elongated spermatids, sustentacular Sertoli and interstitial Leydig cells, with statistically significant differences. In conclusion, prenatal exposure to VPA causes histopathological alterations in the offspring of mice in testicular development, from the embryonic stage to 6 weeks postnatal.

The Microtubule Cytoskeleton during the Early Drosophila Spermiogenesis.

Sperm elongation and nuclear shaping in Drosophila largely depends on the microtubule cytoskeleton that in early spermatids has centrosomal and non-centrosomal origins. We report here an additional γ-tubulin focus localized on the anterior pole of the nucleus in correspondence of the apical end of the perinuclear microtubules that run within the dense complex. The perinuclear microtubules are nucleated by the pericentriolar material, or centriole adjunct, that surrounds the basal body and are retained to play a major role in nuclear shaping. However, we found that both the perinuclear microtubules and the dense complex are present in spermatids lacking centrioles. Therefore, the basal body or the centriole adjunct seem to be dispensable for the organization and assembly of these structures. These observations shed light on a novel localization of γ-tubulin and open a new scenario on the distribution of the microtubules and the organization of the dense complex during early Drosophila spermiogenesis.

Experimental induction and mathematical modeling of Ca2+ dynamics in rat round spermatids.

Cytosolic Ca2+ concentration ([Ca2+ ]) has an important role in spermatozoa and hence it regulates fertilization. In male germinal cells, there are indirect evidences that this ion could regulate physiological processes in spermatogenesis. Since little is known about Ca2+ homeostasis in spermatogenic cells, in this work we propose a mathematical model that accounts for experimental [Ca2+ ] dynamics triggered by blockade of the SERCA transport ATPase with thapsigargin in round rat spermatids, without external Ca2+ and with different extracellular lactate concentrations. The model included three homogeneous calcium compartments and Ca2+-ATPase activities sensitive and insensitive to thapsigargin, and it adjusted satisfactorily the experimental calcium dynamic data. Moreover, an extended version of the model satisfactorily adjusted the stationary states of calcium modulated by extracellular lactate, which is consistent with the participation of a low affinity lactate transporter and further lactate metabolism in these cells. Further studies and modeling would be necessary to shed some light into the relation between Ca2+-lactate-ATP homeostasis and cell-cell interactions in the seminiferous tubules that are expected to modulate Ca2+ dynamics by hormonal factors or energetic substrates in meiotic and postmeiotic spermatogenic cells.

Blocking the Bromodomains Function Contributes to Disturbances in Alga Chara vulgaris Spermatids Differentiation.

Bromodomain containing (BRD) proteins play an essential role in many cellular processes. The aim of this study was to estimate activity of bromodomains during alga Chara vulgaris spermatids differentiation. The effect of a bromodomain inhibitor, JQ1 (100 µM), on the distribution of individual stages of spermatids and their ultrastructure was studied. The material was Feulgen stained and analysed in an electron microscope. JQ1 caused shortening of the early stages of spermiogenesis and a reverse reaction at the later stages. Additionally, in the same antheridium, spermatids at distant developmental stages were present. On the ultrastructural level, chromatin fibril system disorders and significantly distended endoplasmic reticulum (ER) cisternae already at the early stages were observed. Many autolytic vacuoles were also visible. The ultrastructural disturbances intensified after prolonged treatment with JQ1. The obtained data show that JQ1 treatment led to changes in the spermatid number and disturbances in chromatin condensation and to cytoplasm reduction. The current studies show some similarities between C. vulgaris and mammals spermiogenesis. Taken together, these results suggest that JQ1 interferes with the spermatid differentiation on many interdependent levels and seems to induce ER stress, which leads to spermatid degeneration. Studies on the role of bromodomains in algae spermiogenesis have not been conducted so far.

The aryl hydrocarbon receptor mediates sex ratio distortion in the embryos sired by TCDD-exposed male mice.

Many reports describe an association between preconceptional paternal exposure to environmental chemicals, including the persistent organic pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) with an increased number of female offspring. We chronically treated wild-type C57BL/6 male mice with TCDD to investigate a role for the aryl hydrocarbon receptor (AHR) transcription factor. These mice had a 14 % lower male:female sex ratio than control mice, which was not observed in TCDD-treated Ahr knock out mice. AHR target genes Cyp1a1 and Ahrr were upregulated in the liver and testis of WT mice and Ahr expression was higher in the epididymis (2-fold) and liver (18-fold) than in whole testis tissue. The AHR protein was localized to round spermatids, elongating spermatids, and Leydig cells in the testis of WT mice. These studies demonstrate AHR involvement in the sex ratio distortion of TCDD-exposed males and the need for evaluating the molecular and genetic mechanism of this process.

Pomegranate Seeds Extract Possesses a Protective Effect against Tramadol-Induced Testicular Toxicity in Experimental Rats.

Tramadol is a centrally acting opioid analgesic that is extensively used. The chronic exposure to tramadol induces oxidative stress and toxicity especially for patients consuming it several times a day. Previously, we and others reported that tramadol induces testicular damage in rats. This study was conducted to investigate the possible protective effect of pomegranate seed extract (PgSE) against tramadol-induced testicular damage in adult and adolescent rats. Male rats were orally treated with tramadol or in a combination with PgSE for three weeks. Testes were then dissected and analyzed. Histological and ultrastructural examinations indicated that tramadol induced many structural changes in the testes of adult and adolescent rats including hemorrhage of blood vessels, intercellular spaces, interstitial vacuoles, exfoliation of germ cells in lumen, cell apoptosis, chromatin degeneration of elongated spermatids, and malformation of sperm axonemes. Interestingly, these abnormalities were not observed in tramadol/PgSE cotreated rats. The morphometric analysis revealed that tramadol disrupted collagen metabolism by elevating testicular levels of collagen fibers but that was protected in tramadol/PgSE cotreatment at both ages. In addition, DNA ploidy revealed that S phase of the cell cycle was diminished when adult and adolescent rats were treated with tramadol. However, the S phase had a normal cell population in the cotreated adult rats, but adolescent rats had a lower population than controls. Furthermore, the phytochemistry of PgSE revealed a high content of total polyphenols and total flavonoids within this extract; besides, the DPPH free radical scavenging activity was high. In conclusion, this study indicated that PgSE has a prophylactic effect against tramadol-induced testicular damage in both adult and adolescent ages, although the tramadol toxicity was higher in adolescent age to be completely protected. This prophylactic effect might be due to the high antioxidant compounds within the pomegranate seeds.

Arsenic influences spermatogenesis by disorganizing the elongation of spermatids in adult male mice.

Arsenic (As) has become a major problem in maintaining the environment and human health due to its wide application in the production of agriculture and industry. Many studies indicate that As can affect spermatogenesis process and lower sperm quality. However, the undergoing molecular mechanism is unclear. For this, forty-eight 8-week old adult male mice were divided into four groups of twelve each, which were administrated to 0, 0.2, 2, 20 ppm As2O3 in their drinking water respectively for six months. The results showed that As treatment reduced sperm counts and increased the sperm malformation ratio of mice. Interestingly, both the amounts of round and elongated spermatids, and the ratios of spermatids elongation were decreased significantly by As exposure. Furthermore, the structure of Chromatoid Body (CB) which presents a typical nebulous shape in round spermatids after spermatogenesis arrested, and the mRNA expression levels of gene TDRD1, TDRD6 and TDRD7 related to CB were changed by arsenic. Again, the mRNA and protein expression levels of the markers DDX25 and CRM1 in haploid periods of spermatogenesis and the associated proteins HMG2, PGK2, and H4 with DDX25 regulation were declined significantly with As treatment. Taken together; it reveals that As interferes with spermatogenesis by disorganizing the elongation of spermatids. H4, HMG2 and PGK2 are regulated by DDX25 which interacts with CRM1 and may play a vital role in spermatogenesis disorder induced by As exposure, which maybe provides one of the underlying mechanisms for As-induced male reproductive toxicity.

Effects of a mixture of low doses of atrazine and benzo[a]pyrene on the rat seminiferous epithelium either during or after the establishment of the blood-testis barrier in the rat seminiferous tubule culture model.

Atrazine (ATZ), a widely used agricultural pesticide and benzo[a]pyrene (BaP), a ubiquitous environmental human carcinogen can induce alterations of spermatogenesis. In the present study, we showed first that our seminiferous tubule culture model, in bicameral chambers, allowed the settlement of the blood-testis barrier (BTB) in 8-day-old male rat cultures and the differentiation of spermatogonia into round spermatids.The effect of a mixture of 1 µg/L of ATZ and 1 µg/L of BaP was then investigated either during or after the establishment of the BTB by using 8- or 20-22-day-old rats. Cultures were performed over a 3-week period. Our results show that claudin-11 and connexin 43 two proteins of the BTB, were impaired by the mixture which also reduced the number of round spermatids (the direct precursors of spermatozoa), by targeting the middle to late pachytene spermatocytes. These effects were observed in 8- and 20-22-day -old rat seminiferous tubule cultures. However, the decrease of the number of round spermatids was faster and more marked in the 8-day- than in the 20-22-day -old rat seminiferous tubule cultures. Our study emphasizes the possible influence of the age of an individual on the effect of (a) toxicant(s) on spermatogenesis.

Protective effects of Anthocleista djalonensis A. Chev root extracts against induced testicular inflammation and impaired spermatogenesis in adult rats.

This study was designed to explore the protective effects of methanol (Meth, 200 mg kg-1 body wt) and aqueous ethanol (Eth-OH, 200 mg kg-1 body wt) extracts of Anthocleista djalonensis roots on testicular inflammation induced by lipopolysaccharide (LPS, 5 mg/kg body wt) and depletion of tubular germ cells induced by busulfan (15 mg/kg body wt) in rats after 60 days of oral administration. As expected, LPS stimulation of the animals significantly increased serum and intra-testicular interleukin-6 and serum nitrite levels which were significantly inhibited in the Eth-OH + LPS and Meth + LPS animals. The increase in testicular and not serum myeloperoxidase activity that was induced by LPS treatment was synergistically increased in the Eth-OH + LPS animals, whereas it was inhibited in the Meth + LPS animals compared to LPS-treated animals. Furthermore, the administration of the Eth-OH or Meth extracts protected against busulfan-induced depletion of tubular germ cells and promotes the re-population of the seminiferous tubules with germ cells (spermatogonia, spermatocytes and round spermatids) at different stages of development. The extracts were found to contain 7'-oxaspiro [cyclopropane-1,4'-tricyclo [3.3.1.0 (6,8)] nonan-2'-one], cis,cis-7,10-hexadecadienal, hexadecanoic acid, methyl ester, hexadecanoic acid, ethyl ester, 9,12-octadecadienoic acid, methyl ester, and 9,12-octadecadienoic acid (Z,Z)-) which may partly explain the observed anti-inflammatory effects. In conclusion, Meth extracts of A. djanonesis have better anti-inflammatory effects than the Eth-OH extract for the management of impaired testicular function due to inflammation. However both extracts exhibited protective effect on the histology of the testis allowing for the recovery of spermatogenesis.

Transgenerational sperm DNA methylation epimutation developmental origins following ancestral vinclozolin exposure.

A number of environmental factors from nutrition to toxicants have been shown to promote the epigenetic transgenerational inheritance of disease and phenotypic variation. This requires alterations in the germline (sperm or egg) epigenome. Previously, the agricultural fungicide vinclozolin was found to promote the transgenerational inheritance of sperm differential DNA methylation regions (DMRs) termed epimutations that help mediate this epigenetic inheritance. The current study was designed to investigate the developmental origins of the transgenerational DMRs during gametogenesis. Male control and vinclozolin lineage F3 generation rats were used as a source of embryonic day 13 (E13) primordial germ cells, embryonic day 16 (E16) prospermatogonia, postnatal day 10 (P10) spermatogonia, adult pachytene spermatocytes, round spermatids, caput epididymal spermatozoa, and caudal sperm. The DMRs between the control versus vinclozolin lineage samples were determined for each developmental stage. The top 100 statistically significant DMRs for each stage were compared. The developmental origins of the caudal epididymal sperm DMRs were assessed. The chromosomal locations and genomic features of the different stage DMRs were investigated. In addition, the DMR associated genes were identified. Previous studies have demonstrated alterations in the DMRs of primordial germ cells (PGCs). Interestingly, the majority of the DMRs identified in the current study for the caudal sperm originated during the spermatogenic process in the testis. A cascade of epigenetic alterations initiated in the PGCs appears to be required to alter the epigenetic programming during spermatogenesis to modify the sperm epigenome involved in the transgenerational epigenetic inheritance phenomenon.

The effects of hexaconazole and epoxiconazole enantiomers on metabolic profile following exposure to zebrafish (Danio rerio) as well as the histopathological changes.

Hexaconazole and epoxiconazole are the worldwidely used fungicides. However, limited information is known about the toxicological effects of their enantiomers on aquatic organisms. In this study, zebrafish were separately exposed to 100 and 1000 µgL-1 hexaconazole and epoxiconazole enantiomers for 21 d 1H NMR-based metabolomics analysis showed that the exposure of low and high dose of hexaconazole enantiomers altered energy metabolism, lipid metabolism and amino acid metabolism of zebrafish, with the different metabolic profiles resulted from the same dose of (+)-hexaconazole and (-)-hexaconazole. Similar to hexaconazole enantiomers, the metabolic profiles, including the changes related to energy metabolism, lipid metabolism and amino acid metabolism, were demonstrated in low and high dose epoxiconazole enantiomers treatment groups. There are differences in the metabolic profiles of zebrafish between exposed to (+)-epoxiconazole and (-)-epoxiconazole of the same dose. The results of histological examination revealed that the exposure of both enantiomers for hexaconazole and epoxiconazole resulted in the similar histopathological changes. The exposure of hexaconazole and epoxiconazole enantiomers at low and high dose resulted the vacuolization and swell in the liver of the female and male zebrafish. Compared to female zebrafish, more liver damage was found in male zebrafish in the hexaconazole enantiomers exposure groups. The reduction of spermatids was observed in hexaconazole and epoxiconazole enantiomers treatment groups of both doses. Hexaconazole enantiomers exposure of low and high dose resulted the increase in the number of mature eggs, while such effect was not observed in epoxiconazole enantiomers exposure groups. Hexaconazole and epoxiconazole enantiomers exposure resulted in no changes in brains of female and male zebrafish. As a result, both triazole-based chiral bactericides, hexaconazole and epoxiconazole, have similar toxicological effects but their mechanisms of action are not exactly the same. The above results will play an important part in making the differences in toxic effects of hexaconazole and epoxiconazole enantiomers clear. What's more, it is an indispensable part for an integrated environmental risk assessment.

Differential cell death decisions in the testis: evidence for an exclusive window of ferroptosis in round spermatids.

Oxidative stress is a major aetiology in many pathologies, including that of male infertility. Recent evidence in somatic cells has linked oxidative stress to the induction of a novel cell death modality termed ferroptosis. However, the induction of this iron-regulated, caspase-independent cell death pathway has never been explored outside of the soma. Ferroptosis is initiated through the inactivation of the lipid repair enzyme glutathione peroxidase 4 (GPX4) and is exacerbated by the activity of arachidonate 15-lipoxygenase (ALOX15), a lipoxygenase enzyme that facilitates lipid degradation. Here, we demonstrate that male germ cells of the mouse exhibit hallmarks of ferroptosis including; a caspase-independent decline in viability following exposure to oxidative stress conditions induced by the electrophile 4-hydroxynonenal or the ferroptosis activators (erastin and RSL3), as well as a reciprocal upregulation of ALOX15 and down regulation of GPX4 protein expression. Moreover, the round spermatid developmental stage may be sensitized to ferroptosis via the action of acyl-CoA synthetase long-chain family member 4 (ACSL4), which modifies membrane lipid composition in a manner favourable to lipid peroxidation. This work provides a clear impetus to explore the contribution of ferroptosis to the demise of germline cells during periods of acute stress in in vivo models.

Effect of Fe and Cd Co-Exposure on Testicular Steroid Metabolism, Morphometry, and Spermatogenesis in Mice.

The mechanism of testicular toxicity of simultaneous multiple exposures to metals is poorly understood. Previous studies reported that the toxic effect of cadmium (Cd) is modified by tissue concentration of iron (Fe). Using the mice (Mus musculus) model in the present study, we demonstrated that combined Cd (25 mg kg-1 bw) and Fe (100 mg kg-1 bw) treatment increased both Cd and Fe testicular concentrations much more than separate exposures to either of the metals. Intratesticular Cd and Fe concentrations were inversely correlated (r = - 0.731, p < 0.05) on administration of Fe but not on combined exposure to both metals when they were positively correlated (versus Cd; r = 0.793, versus Fe; r = 0.779, p < 0.05). Additionally, Cd + Fe treatment increased testicular lipid peroxidation and depleted intratestesticular testosterone, cholesterol and glutathione concentrations much more than their separate treatment. This was also associated with decreased activity of the germ cell marker, testicular lactate dehydrogenase, and increased testicular myeloperoxidase activity. These changes resulted in decreased seminiferous epithelial height, tubular diameter, germ cell (spermatogonia, spermatocytes, and spermatids) numbers, and severe tissue damage. In conclusion, Cd + Fe intake have synergistic toxic effects on testicular steroid formation and spermatogenesis due to the high testicular concentrations of both metals.

Abolition of prenatal lipopolysaccharide-induced reproductive disorders in rat male offspring by fulvestrant.

During prenatal and early postnatal periods of development, multiple environmental factors have profound and long-lasting effects on the immune and reproductive functions. The aim of this study was to investigate the effects of maternal lipopolysaccharide (LPS) exposure (50 mg/kg, i.p.) at day 12 of pregnancy and estradiol antagonist treatment (fulvestrant, 1.5 mg/kg, s.c. in neck) at postnatal days 5-14 (PND5-14) with high estradiol levels on reproductive parameters in adult rat males. Serum steroid concentrations were measured in male offspring at PND80 by ELISA. Body, testis weights and ano-genital distance (AGD) were recorded at different stages of postnatal development. Testis was also processed to cytohistological studies at PND80. Our results demonstrate that body weight was decreased from PND14 to 30 after prenatal LPS treatment and was increased after fulvestrant treatment. AGD was decreased after prenatal LPS treatment and was increased after fulvestrant injections. Testis weight, testosterone level, seminiferous tubule diameter, and number of Sertoli and spermatid cells were also decreased in rats exposed prenatally to LPS and were restored to the normal control level after fulvestrant treatment. According to results, we can conclude that the development of sexual disorders in males after prenatal immune stress is potentiated by estradiol during the pre-pubertal period.

Evaluation of an in vitro mouse testis organ culture system for assessing male reproductive toxicity.

BACKGROUND: Development of an in vitro system capable of producing mature sperm remains a challenging goal, with only few successes reported. Such a system, could be used to test agents for potential toxicity to the male reproductive system; to explore this, we exposed immature mouse testis fragments in culture to ethinylestradiol (EE), a well-known testicular toxicant in vivo. METHODS: Testis fragments from postnatal day 5 mice were cultured in Albumax I medium. After 24 hr of culture, fragments were treated with 0.01, 0.1 or 1 nM EE, then harvested after 20 days in culture and examined for histology or gene expression measures by quantitative PCR. RESULTS: There was substantial variability between fragments in the degree of spermatogenesis observed. The percentage of seminiferous tubules containing any dead germ cells increased as a result of EE exposure in a dose dependent fashion. This was accompanied with a decreased percentage of tubules with round spermatids. Expression of estrogen receptor 1, cytochrome P450, family 11, subfamily a, and polypeptide 1 also was reduced, depending on the dose. CONCLUSION: These gene expression changes in the testis fragments are similar to those seen after animals have been exposed to EE. Gene expression changes in testis fragments are encouraging, but the variability across samples will need to be reduced for this in vitro system to become a generally applicable method for assessing testicular toxicants.

Induction of spermiation using Ovaprim™ with topical gill method in the silver rasbora (Rasbora argyrotaenia).

The main obstacles on silver rasbora (Rasbora argyrotaenia) culture are having the limited number of broodstock and spawning depending on the season. The purpose of this study was to determine the effect of different dosage of Ovaprim™ induction by topical gill method to silver rasbora spermiation in order to continue the production out of its reproduction season with an optimum dose. A total of 30 male fish with a weight of 7.78 ±â€¯0.20 g and length 4.11 ±â€¯0.31 cm was used in this research. Topical gill treatments of Ovaprim™ were administered with following doses; 0.15 µl/g, 0.25 µl/g, 0.35 µl/g, 0.45 µl/g and 0.55 µl/g body weight. Milt volume, sperm concentration, sperm motility, and sperm viability parameters were observed in this study to understand the optimum dose of Ovaprim™ for male silver rasbora breeders. Spermiation induction of silver rasbora using Ovaprim™ with topical gill method has been successfully carried out, indicating an increase (P < 0.05) in milt volume, sperm concentration, sperm motility, and sperm viability. According to results a dose of Ovaprim™ is recommended to be used the 0.25 µl/g body weight in the spermiation induction of silver rasbora.

Dynein 1 supports spermatid transport and spermiation during spermatogenesis in the rat testis.

In the mammalian testis, spermatogenesis is dependent on the microtubule (MT)-specific motor proteins, such as dynein 1, that serve as the engine to support germ cell and organelle transport across the seminiferous epithelium at different stages of the epithelial cycle. Yet the underlying molecular mechanism(s) that support this series of cellular events remain unknown. Herein, we used RNAi to knockdown cytoplasmic dynein 1 heavy chain (Dync1h1) and an inhibitor ciliobrevin D to inactivate dynein in Sertoli cells in vitro and the testis in vivo, thereby probing the role of dynein 1 in spermatogenesis. Both treatments were shown to extensively induce disruption of MT organization across Sertoli cells in vitro and the testis in vivo. These changes also perturbed the transport of spermatids and other organelles (such as phagosomes) across the epithelium. These changes thus led to disruption of spermatogenesis. Interestingly, the knockdown of dynein 1 or its inactivation by ciliobrevin D also perturbed gross disruption of F-actin across the Sertoli cells in vitro and the seminiferous epithelium in vivo, illustrating there are cross talks between the two cytoskeletons in the testis. In summary, these findings confirm the role of cytoplasmic dynein 1 to support the transport of spermatids and organelles across the seminiferous epithelium during the epithelial cycle of spermatogenesis.

Generation of haploid spermatids from chicken embryonal primordial germ cells.

In vitro production of functional spermatids has special significance in the research of spermatogenesis and the treatment of male infertility. Primordial germ cells (PGCs) are the precursors of oocyte and sperm, which generate the totipotent cells. Studies have shown that PGCs have the potential ability to develop meiotic spermatids in vitro. Here we have shown that retinoic acid (RA) leads to PGC differentiation, and SCF can improve the efficiency of induction. We indicate an efficient approach to produce haploid spermatids from chicken PGCs in the presence of RA and stem cell factor (SCF). Real-time RT-PCR assays showed that RA and SCF induced a remarkable increase in expression of SYCP1, ACR, BOULE and DCM1 of meiotic germ cells and haploid germ cells, respectively. DNA content assays revealed that RA and SCF induced a remarkable increase of haploid cells. This study provides a theoretical basis and a great animal model for spermatogenesis study.

Protective effect of Nigella sativa oil against acetamiprid induced reproductive toxicity in male rats.

The present study was designed to investigate the adverse reproductive effects of acetamiprid, besides the possible protective role of Nigella sativa oil (NSO), as a potential antioxidant agent. Thirty-two male Wistar rats were allocated into four equal groups of eight, control (CRL), acetamiprid (ACMP, 27 mg/kg), Nigella sativa oil (NSO, 0.5 ml/kg) and in combination (ACMP + NSO). The experimental animals were dosed by gavage (5 days per week) for 45 consecutive days. Body weight gain, reproductive organs weights, sperm characteristics, testosterone, and thiobarbutiric acid-reactive substances (TBARS) levels were investigated. The obtained results showed that ACMP decreased significantly (p < 0.001) the body weight gain and the absolute weights of reproductive organs (testes, epididymis, and seminal vesicles). Furthermore, significant alterations at least (p < 0.01) in semen characteristics were noted in ACMP group as evidenced by a decline in spermatids number, sperm count, sperm motility, and testosterone level with an increase in abnormal and dead sperm and TBARS level. Treatment with NSO alone may stimulate spermatogenesis, increased significantly (p < 0.001) spermatids number and the weight of seminal vesicles. On the other hand, the co-administration of NSO along with ACMP can mitigate more efficiently and modulate in certain cases the adverse effects induced by ACMP on reproductive organs weights, semen quality, testosterone, and TBARS levels (at least p < 0.001). This obvious protective role of NSO against ACMP induced reproductive toxicity may be due to its antioxidant properties and ability to reduce TBARS levels as shown in this work.