Delay in puberty indices of Wistar rats caused by Cadmium. Focus on the redox system in reproductive organs.

Puberty is a transitional period from juvenile stage to adulthood, followed by the functional maturation of gonads and reproductive organs. This period is sensitive to environmental pollutants like cadmium (Cd), a heavy metal that represents a serious health risk. Cd is an endocrine disruptor that interferes with reproduction by causing oxidative stress in the reproductive organs, affecting the sexual function and decreasing testosterone (T) levels. However, little research has been done on the effects of Cd on puberty markers and antioxidant systems. In this study, we evaluated the effects of Cd on puberty markers: preputial separation, testes descent and T levels, and the antioxidant activity (SOD, CAT, GSH/GSSG and TAC) in the seminal vesicles, testis and epididymis. Male Wistar pups were treated with 1 mg/kg Cd or saline solution by i.p. injection from day 1 to 35; the other treatment was administrated for 49 days. At the end of treatment, the animals were sacrificed, and the tissues of interest dissected, weighed and prepared for the respective assays. Cd treated rats from birth to puberty showed a delay onset in the puberty markers and a low weight in reproductive organs. Also, Cd induced differential effects on the redox system in reproductive organs and decreased T levels, these effects played a pivotal role in the delay of puberty markers onset (testes descent and preputial separation), affecting the development and sexual maturity of the male rats.

Bisphenol S alters development of the male mouse mammary gland and sensitizes it to a peripubertal estrogen challenge.

Humans are exposed to estrogenic chemicals in food and food packaging, personal care products, and other industrial and consumer goods. Bisphenol A (BPA), a well-studied xenoestrogen, is known to alter development of estrogen-sensitive organs including the brain, reproductive tract, and mammary gland. Bisphenol S (BPS; 4,4'-sulfonyldiphenol), which has a similar chemical structure to BPA, is also used in many consumer products, but its effects on estrogen-sensitive organs in mammals has not been thoroughly examined. Here, we quantified the effects of perinatal exposures to BPS on the male mouse mammary gland. In our first study, pregnant CD-1 mice were orally exposed to BPS (2 or 200 µg/kg/day) starting on pregnancy day 9 through lactation day 20, and male mammary glands were evaluated on embryonic day 16, prior to puberty, and in early adulthood. We observed modest changes in tissue organization in the fetal gland, and significant increases in growth of the gland induced by developmental BPS exposure in adulthood. In our second study, pregnant CD-1 mice were orally exposed to BPS (2, 200 or 2000 µg/kg/day) starting on pregnancy day 9 through lactational day 2. After weaning, the male pups were administered either oil (vehicle) or an estrogen challenge (1 µg ethinyl estradiol/kg/day) for ten days starting prior to puberty. After the 10-day estrogen challenge, we examined hormone-sensitive outcomes including anogenital index (AGI), weight of the seminal vesicles, and morphological parameters of the mammary gland. Although AGI and seminal vesicle weight were not affected by BPS, we observed dose-specific effects on the response of male mammary glands to the peripubertal estrogen challenge. Because male mammary glands are structurally less developed compared to females, they may provide a simple model tissue to evaluate the effects of putative xenoestrogens.

Quantitative (stereological) study of the epididymis and seminal vesicle in the rat from young to old.

There is a scarcity of morphometric data on the developmental and ageing changes in the epididymis and seminal vesicle in young and old rats. Eighty-six normal male Sprague-Dawley rats were randomly sampled from a cohort of animals aged 1-36 months (7-9 animals each age group). The epididymis and seminal vesicle (with the closely attached coagulating gland) were removed, and methacrylate resin-embedded sections were prepared for quantitative study of key histological structures by light microscopy. Stereological methods (point counting and optical disector) were used to estimate the total volumes of sperm mass, secretion (glandular lumen) and other structures and the number of spermatozoa. The results showed that the rapid growth of the reproductive organs was between 1 and 4 months of age. The epididymis stored the largest volume of sperm mass or number of spermatozoa at 12 months of age, but thereafter until 36 months of age, the sperm storage did not markedly diminish. The volume of secretion stored in the seminal vesicular gland declined by more than 35% from a plateau at 12-18 months until 36 months of age while that in the coagulating gland declined by more than 30% from a plateau at 18-24 months until 36 months of age.

Junctional adhesion molecule A: expression in the murine epididymal tract and accessory organs and acquisition by maturing sperm.

STUDY QUESTION: Is junctional adhesion molecule A (JAM-A), a sperm protein essential for normal motility, expressed in the murine post-testicular pathway and involved in sperm maturation? SUMMARY ANSWER: JAM-A is present in the prostate and seminal vesicles and in all three regions of the epididymis where it is secreted in epididymosomes in the luminal fluid and can be delivered to sperm in vitro. WHAT IS KNOWN ALREADY: JAM-A shares with the plasma membrane Ca2+ATPase 4 (PMCA4, the major Ca2+ efflux pump in murine sperm) a common interacting partner, CASK (Ca2+/CaM-dependent serine kinase). JAM-A, like PMCA4, plays a role in Ca2+ regulation, since deletion of Jam-A results in significantly elevated intracellular Ca2+ levels and reduced sperm motility. Recently, PMCA4 was reported to be expressed in the epididymis and along with CASK was shown to be in a complex on epididymosomes where it was transferred to sperm. Because of the association of JAM-A with CASK in sperm and because of the presence of PMCA4 and CASK in the epididymis, the present study was performed to determine whether JAM-A is expressed in the epididymis and delivered to sperm during their maturation. STUDY DESIGN, SIZE, DURATION: The epididymides, prostate and seminal vesicles were collected from sexually mature C57BL/6J and Institute for Cancer Research mice and antibodies specific for JAM-A and Ser285 -phosphorylated JAM-A (pJAM-A) were used for the analysis. Tissues, sperm and epididymal luminal fluid (ELF) were studied. Epididymosomes were also isolated for study. Caput and caudal sperm were co-incubated with ELF individually to determine their abilities to acquire JAM-A in vitro. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sections of all three regions of the epididymis were subjected to indirect immunofluorescence analysis. Epididymal tissues, fluid, sperm, prostate and seminal vesicle tissues were analyzed for JAM-A and/or pJAM-A via western blotting analysis. The relative amounts of JAM-A and pJAM-A among epididymal tissues, ELF and sperm were detected by western blot via quantification of band intensities. Epididymosomes were isolated by ultracentrifugation of the ELF after it was clarified to remove cells and tissue fragments, and the proteins western blotted for JAM-A and pJAM-A, and exosomal biochemical markers. FACS analysis was used to quantify the amount of JAM-A present on caput and caudal sperm, as well as the amount of JAM-A acquired in vitro after their co-incubation with ELF. MAIN RESULTS AND THE ROLE OF CHANCE: Western blots revealed that JAM-A is expressed in all three regions of the epididymis, the prostate and seminal vesicles. As confirmed by indirect immunofluorescence, a western blot showed that JAM-A has a higher expression in the corpus and caudal regions, where it is significantly (P < 0.01) more abundant than in the caput. Both JAM-A and Ser285-phosphorylated JAM-A (pJAM-A) are secreted into the ELF where it is highest in the distal regions. In the ELF, both JAM-A and pJAM-A were detected in epididymosomes. Western blotting of sperm proteins showed a significant (P < 0.01) increase of JAM-A and pJAM-A in caudal, compared with caput, sperm. Flow-cytometric analysis confirmed the increase in JAM-A in caudal sperm where it was 1.4-fold higher than in caput ones. Co-incubation of caput and caudal sperm with ELF demonstrated ~2.3- and ~1.3-fold increases, respectively, in JAM-A levels indicating that epididymosomes transfer more JAM-A to caput sperm that are less saturated with the protein than caudal ones. LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: First, although the ELF was clarified prior to ultracentrifugation for epididymosome isolation, we cannot rule out contamination of the epididymosomal proteins by those from epididymal epithelial cells. Second, the JAM-A detected in the prostate and seminal vesicles might not necessarily be secreted from those organs and may only be present within the tissues, where it would be unable to impact sperm in the ejaculate. WIDER IMPLICATIONS OF THE FINDINGS: Although performed in the mouse the study has implications for humans, as the highly conserved JAM-A is a signaling protein in human sperm. There is physiological significance to the finding that JAM-A, which regulates sperm motility and intracellular Ca2+, exists in elevated levels in the cauda where sperm gain motility and fertilizing ability. The study suggests that the acquisition of JAM-A in the epididymal tract is involved in the mechanism by which sperm gain their motility during epididymal maturation. This increased understanding of sperm physiology is important for aspects of ART. STUDY FUNDING AND COMPETING INTEREST(S): The work was supported by NIH-RO3HD073523 and NIH-5P20RR015588 grants to P.A.M.-D. The authors declare there are no conflicts of interests.

Impact of titanium dioxide on androgen receptors, seminal vesicles and thyroid hormones of male rats: possible protective trial with aged garlic extract.

The aim of this study was to evaluate the effect of titanium dioxide (TiO2 ), a widely produced and consumed pigment in various food products, on the post-natal development of male albino rat seminal vesicle and thyroid hormones, as well as to evaluate the ameliorative effect of aged garlic extract (AGE) on TiO2 -induced alterations. Forty male rat pups (3 weeks old) were divided into four equal groups. The 1st group received distilled water orally (control group), 2nd group was given 2 ml kg-1 AGE, 3rd group was administered TiO2 (5 g kg-1 BW) day after day for 65 days, and the 4th group administered AGE 6 hr prior to TiO2 gavage. TiO2 -exposed rats showed nonsignificant changes in the serum testosterone, TSH, T3 and T4 , while serum glucose showed a significant decrease. Androgen receptor (AR) mRNA expression was significantly down-regulated and weak signal of AR immune labelling. Histopathologically, the epithelium cell lining of seminal vesicles showed focal areas of necrosis and fibrous tissue with the prominent fibrous stroma of the atrophied glands. Meanwhile, AGE supplementation ameliorated the deleterious effects of TiO2 intoxication through protecting the tissues from oxidative stress caused by TiO2 . In summary, oral administration of TiO2 resulted in abnormal developmental events in male rat seminal vesicle and AGE able to reduce TiO2 toxicity.

Postnatal expression of bone morphogenetic proteins and their receptors in the mouse testis.

TGF-beta superfamily members including bone morphogenetic proteins (BMPs) and their receptors (BMPR-1A, -1B and -2) have been shown to be important for reproductive function in both males and females, while information on the role of BMPs in males is limited. Functional studies on select BMPs and BMP receptors have demonstrated vital roles for these proteins in somatic and germ cell proliferation, steroidogenesis and overall fertility. In order to gain insight into the importance of these genes during postnatal reproductive development in males, our study was undertaken to specify the distribution of BMP and BMPR mRNA in male reproductive and steroidogenic tissues and quantify these genes in the testis using the mouse as our model. We screened testis at two, four, six and eight weeks of age for the expression of ten BMPs and three BMP receptors using RT-qPCR. All three BMP receptor mRNAs - Bmpr1a, Bmpr1b and Bmpr2, and ten BMP mRNAs - Bmp2, Bmp3, Bmp3b, Bmp4, Bmp5, Bmp6, Bmp7, Bmp8a, Bmp8b and Bmp15 were expressed in mouse testis at all stages screened. Testicular expression of genes varied within age groups and at specific developmental stages. Our study establishes an extensive BMP system in mouse reproductive and steroidogenic tissues.

Cloning, sequence characterization, and expression patterns of members of the porcine TSSK family.

Testis-specific serine kinases (TSSKs) are a family of serine/threonine kinases highly expressed in the testes that are responsible for regulating many spermatogenesis-related protein activities. Mutations in this family have a positive relationship with oligospermia and azoospermia in human and mouse. Here, five members of the TSSK family from a Banna mini-pig inbred line (BMI) were cloned, sequenced, and characterized. The full-length coding sequences of BMI TSSKs varied from 807 (TSSK3) to 1095 bp (TSSK1) and encoded 268 to 364 amino acids with molecular weights in the range 30.11 to 41.34 kDa. Following comparison with TSSK4 genes in other species, BMI TSSK4 was found to contain three alternatively spliced variants, inform1, inform 3, and inform 4. BMI TSSK1 and TSSK2 are co-localized on the Sus scrofa chromosome (SSC) 14, and consist of a single exon; TSSK3, TSSK4, and TSSK6 are on SSC6, SSC7, and SSC2, and consist of two, four, and one exon, respectively. Multiple protein sequence alignment and phylogenetic analysis showed that the regions spanning the S_TKc domains were more conserved between pig and other animals: with TSSK1 and TSSK2 and TSSK3 and TSSK6 displaying the greatest degree of homology across species, and the TSSK4 protein clearly distinct from other members. Multi-tissue RT-PCR showed BMI TSSK1, TSSK3, and TSSK4 were only expressed in the testes and seminal vesicle, TSSK2 was confined to testes only, while TSSK6 was expressed widely in adult tissues but was highest in the testes.

Prolonged exposure to acetaminophen reduces testosterone production by the human fetal testis in a xenograft model.

Most common male reproductive disorders are linked to lower testosterone exposure in fetal life, although the factors responsible for suppressing fetal testosterone remain largely unknown. Protracted use of acetaminophen during pregnancy is associated with increased risk of cryptorchidism in sons, but effects on fetal testosterone production have not been demonstrated. We used a validated xenograft model to expose human fetal testes to clinically relevant doses and regimens of acetaminophen. Exposure to a therapeutic dose of acetaminophen for 7 days significantly reduced plasma testosterone (45% reduction; P = 0.025) and seminal vesicle weight (a biomarker of androgen exposure; 18% reduction; P = 0.005) in castrate host mice bearing human fetal testis xenografts, whereas acetaminophen exposure for just 1 day did not alter either parameter. Plasma acetaminophen concentrations (at 1 hour after the final dose) in exposed host mice were substantially below those reported in humans after a therapeutic oral dose. Subsequent in utero exposure studies in rats indicated that the acetaminophen-induced reduction in testosterone likely results from reduced expression of key steroidogenic enzymes (Cyp11a1, Cyp17a1). Our results suggest that protracted use of acetaminophen (1 week) may suppress fetal testosterone production, which could have adverse consequences. Further studies are required to establish the dose-response and treatment-duration relationships to delineate the maximum dose and treatment period without this adverse effect.

ß-CateninC429S mice exhibit sterility consequent to spatiotemporally sustained Wnt signalling in the internal genitalia.

Wnt/ß-catenin signalling regulates numerous developmental and homeostatic processes. Ctnnb1 (also known as ß-catenin) is the only protein that transmits signals from various Wnt ligands to downstream genes. In this study, we report that our newly established mouse strain, which harbours a Cys429 to Ser missense mutation in the ß-catenin gene, exhibited specific organ defects in contrast to mice with broadly functioning Wnt/ß-catenin signalling. Both homozygous mutant males and females produced normal gametes but were infertile because of abnormal seminal vesicle and vaginal morphogenesis. An ins-TOPGAL transgenic reporter spatiotemporally sustained Wnt/ß-catenin signalling during the corresponding organogenesis. Therefore, ß-catenin(C429S) should provide new insights into ß-catenin as a universal component of Wnt/ß-catenin signal transduction.

Hormone-induced and DNA demethylation-induced relief of a tissue-specific and developmentally regulated block in transcriptional elongation.

Genome-wide studies have revealed that genes commonly have a high density of RNA polymerase II just downstream of the transcription start site. This has raised the possibility that genes are commonly regulated by transcriptional elongation, but this remains largely untested in vivo, particularly in vertebrates. Here, we show that the proximal promoter from the Rhox5 homeobox gene recruits polymerase II and begins elongating in all tissues and cell lines that we tested, but it only completes elongation in a tissue-specific and developmentally regulated manner. Relief of the elongation block is associated with recruitment of the elongation factor P-TEFb, the co-activator GRIP1, the chromatin remodeling factor BRG1, and specific histone modifications. We provide evidence that two mechanisms relieve the elongation block at the proximal promoter: demethylation and recruitment of androgen receptor. Together, our findings support a model in which promoter proximal pausing helps confer tissue-specific and developmental gene expression through a mechanism regulated by DNA demethylation-dependent nuclear hormone receptor recruitment.

Galactosyltransferase 4 is a major control point for glycan branching in N-linked glycosylation.

Protein N-glycosylation is a common post-translational modification that produces a complex array of branched glycan structures. The levels of branching, or antennarity, give rise to differential biological activities for single glycoproteins. However, the precise mechanism controlling the glycan branching and glycosylation network is unknown. Here, we constructed quantitative mathematical models of N-linked glycosylation that predicted new control points for glycan branching. Galactosyltransferase, which acts on N-acetylglucosamine residues, was unexpectedly found to control metabolic flux through the glycosylation pathway and the level of final antennarity of nascent protein produced in the Golgi network. To further investigate the biological consequences of glycan branching in nascent proteins, we glycoengineered a series of mammalian cells overexpressing human chorionic gonadotropin (hCG). We identified a mechanism in which galactosyltransferase 4 isoform regulated N-glycan branching on the nascent protein, subsequently controlling biological activity in an in vivo model of hCG activity. We found that galactosyltransferase 4 is a major control point for glycan branching decisions taken in the Golgi of the cell, which might ultimately control the biological activity of nascent glycoprotein.

Maternal LPS exposure during pregnancy impairs testicular development, steroidogenesis and spermatogenesis in male offspring.

Lipopolysaccharide (LPS) is associated with adverse developmental outcomes including embryonic resorption, fetal death, congenital teratogenesis and fetal growth retardation. Here, we explored the effects of maternal LPS exposure during pregnancy on testicular development, steroidogenesis and spermatogenesis in male offspring. The pregnant mice were intraperitoneally injected with LPS (50 µg/kg) daily from gestational day (GD) 13 to GD 17. At fetal period, a significant decrease in body weight and abnormal Leydig cell aggregations were observed in males whose mothers were exposed to LPS during pregnancy. At postnatal day (PND) 26, anogenital distance (AGD), a sensitive index of altered androgen action, was markedly reduced in male pups whose mothers were exposed to LPS daily from GD13 to GD 17. At PND35, the weight of testes, prostates and seminal vesicles, and serum testosterone (T) level were significantly decreased in LPS-treated male pups. At adulthood, the number of sperm was significantly decreased in male offspring whose mothers were exposed to LPS on GD 13-17. Maternal LPS exposure during gestation obviously diminished the percent of seminiferous tubules in stages I-VI, increased the percent of seminiferous tubules in stages IX-XII, and caused massive sloughing of germ cells in seminiferous tubules in mouse testes. Moreover, maternal LPS exposure significantly reduced serum T level in male mice whose mothers were exposed to LPS challenge during pregnancy. Taken together, these results suggest that maternal LPS exposure during pregnancy disrupts T production. The decreased T synthesis might be associated with LPS-induced impairments for spermatogenesis in male offspring.

Pharmacologic profiles of investigational kisspeptin/metastin analogues, TAK-448 and TAK-683, in adult male rats in comparison to the GnRH analogue leuprolide.

Kisspeptin/metastin, a hypothalamic peptide, plays a pivotal role in controlling gonadotropin-releasing hormone (GnRH) neurons, and we have shown that continuous subcutaneous administration of kisspeptin analogues suppresses plasma testosterone in male rats. This study examined pharmacologic profiles of investigational kisspeptin analogues, TAK-448 and TAK-683, in male rats. Both analogues showed high receptor-binding affinity and potent and full agonistic activity for rat KISS1R, which were comparable to natural peptide Kp-10. A daily subcutaneous injection of TAK-448 and TAK-683 (0.008-8µmol/kg) for consecutive 7 days initially induced an increase in plasma luteinizing hormone and testosterone levels; however, after day 7, plasma hormone levels and genital organ weights were reduced. Continuous subcutaneous administrations of TAK-448 (≥10pmol/h, ca. 0.7nmol/kg/day) and TAK-683 (≥30pmol/h, ca. 2.1nmol/kg/day) induced a transient increase in plasma testosterone, followed by abrupt reduction of plasma testosterone to castrate levels within 3-7 days. This profound testosterone-lowering effect was sustained throughout 4-week dosing periods. At those dose levels, the weights of the prostate and seminal vesicles were reduced to castrate levels. These suppressive effects of kisspeptin analogues were more rapid and profound than those induced by the GnRH agonist analogue leuprolide treatment. In addition, TAK-683 reduced plasma prostate specific antigen (PSA) in the JDCaP androgen-dependent prostate cancer rat model. Thus, chronic administration of kisspeptin analogues may hold promise as a novel therapeutic approach for suppressing reproductive functions and hormone-related diseases such as prostate cancer. Further studies are warranted to elucidate clinical significance of TAK-448 and TAK-683.

Modulation of lipocalin-type prostaglandin D2 synthase expression in catfish seminal vesicles by thyroid disrupting agents and hormones.

Thyroid hormones play crucial role in several biological processes including reproduction. Disruption of normal thyroid status by environmental contaminants can cause severe impairment in reproductive functions. In our previous study, we reported down-regulation of a protein in seminal vesicular fluid of air-breathing catfish, Clarias gariepinus during experimentally induced hyperthyroidism. N-terminal amino acid sequence analysis followed by search in sequence database denoted it to be lipocalin-type prostaglandin D2 synthase (ptgds-b). In the present study, we cloned full-length cDNA of ptgds-b based on the N-terminal amino acid sequence. Surprisingly, Northern blot as well as RT-PCR analysis demonstrated the presence of ptgds-b transcript predominantly in seminal vesicles and developing testis. Further, ptgds-b mRNA significantly decreased in seminal vesicles following L-thyroxine overdose while there was an increased expression of ptgds-b after depletion of thyroid hormone by thiourea and withdrawal of the treatments reverted this effect. Treatment of catfish with human chorionic gonadotropin and estradiol significantly reduced ptgds-b expression. Taken together, we report ptgds-b as a thyroid hormone regulated protein in the seminal vesicles in addition to gonadotropin and estradiol. Further studies might explain the exclusive presence of ptgds-b in seminal vesicles and developing testis yet present data evaluated it as a putative biomarker for thyroid hormone disruption.

AZD3514: a small molecule that modulates androgen receptor signaling and function in vitro and in vivo.

Continued androgen receptor (AR) expression and signaling is a key driver in castration-resistant prostate cancer (CRPC) after classical androgen ablation therapies have failed, and therefore remains a target for the treatment of progressive disease. Here, we describe the biological characterization of AZD3514, an orally bioavailable drug that inhibits androgen-dependent and -independent AR signaling. AZD3514 modulates AR signaling through two distinct mechanisms, an inhibition of ligand-driven nuclear translocation of AR and a downregulation of receptor levels, both of which were observed in vitro and in vivo. AZD3514 inhibited testosterone-driven seminal vesicle development in juvenile male rats and the growth of androgen-dependent Dunning R3327H prostate tumors in adult rats. Furthermore, this class of compound showed antitumor activity in the HID28 mouse model of CRPC in vivo. AZD3514 is currently in phase I clinical evaluation.

Photoperiod history-dependent responses to intermediate day lengths engage hypothalamic iodothyronine deiodinase type III mRNA expression.

Perihypothalamic thyroid hormone signaling features prominently in the seasonal control of reproductive physiology. Triiodothyronine (T(3)) signaling stimulates gonadal development, and decrements in T(3) signaling are associated with gonadal regression. Type 3 iodothyronine deiodinase (DIO3) converts the prohormone thyroxine (T(4)) into biologically inactive 3,3',5'-triiodothyronine, and in long-day breeding Siberian hamsters exposure to long (LD) and short (SD) photoperiods, respectively, inhibit and stimulate hypothalamic dio3 mRNA expression. Reproductive responses to intermediate-duration photoperiods (IntD) occur in a history-dependent manner; IntDs are interpreted as inhibitory only when preceded by longer photoperiods. Because dio3 expression has only been evaluated under LD or SD photoperiods, it is not known whether hypothalamic dio3 encodes absolute photoperiod duration or the reproductive interpretation of photoperiod. Male Siberian hamsters with and without a prior history of LD were exposed to IntD photoperiods, and hypothalamic dio3 mRNA expression was measured 6 wk later. Hamsters with a LD photoperiod history exhibited gonadal regression in IntD and a marked upregulation of hypothalamic dio3 expression, whereas in hamsters without prior exposure to LD, gonadal responses to IntD were absent, and dio3 expression remained low. Patterns of deiodinase expression in hamsters maintained in chronic IntD photoperiods did not appear to reflect feedback effects of gonadal status. Hypothalamic expression of dio3 does not exclusively reflect ambient photoperiod, but rather the context-dependent reproductive interpretation of photoperiod. Neuroendocrine mechanisms that compare current and prior photoperiods, which permit detection of directional changes in day length, occur either upstream, or at the level, of hypothalamic dio3 expression.

Screening for in vivo (anti)estrogenic and (anti)androgenic activities of Tropaeolum majus L. and its effect on uterine contractility.

ETHNOPHARMACOLOGICAL RELEVANCE: Tropaeolum majus L. (Tropaeolaceae) is a medicinal herb popularly used in Brazil for treatment of inflammatory and cardiovascular diseases. Despite some published data on its efficacy, there are still few toxicological data describing the safety of this plant. The aim of this study was to evaluate the (anti)estrogenic and (anti)androgenic activity of the hydroethanolic extract obtained from Tropaeolum majus L. (HETM), as well as its possible effects on uterine contractility. MATERIALS AND METHODS: Three experimental protocols were performed, (a) uterotrophic assay, (b) Hershberger assay and (c) an ex vivo test to investigate the effects of maternal administration of HETM on uterine contractility at the end of pregnancy. In all protocols three doses of the HETM were administered to Wistar rats: 3, 30 and 300mg/kg. RESULTS: In vivo tests for detection of (anti)androgenic and (anti)estrogenic activities did not show any significant alterations. Similarly, no alterations were observed on uterine contractility induced by oxytocin and arachidonic acid. CONCLUSIONS: HETM was unable to produce (anti)estrogenic or (anti)androgenic activities in the short-term in vivo screening assays performed. In addition, there was no evidence that HETM can affect uterine contractility following gestational exposure of rats.

Gonadal status of male recipient mice influences germ cell development in immature buffalo testis tissue xenograft.

Growth and development of immature testis xenograft from various domestic mammals has been shown in mouse recipients; however, buffalo testis xenografts have not been reported to date. In this study, small fragments of testis tissue from 8-week-old buffalo calves were implanted subcutaneously onto the back of immunodeficient male mouse recipients, which were either castrated or left intact (non-castrated). The xenografts were retrieved and analyzed 12 and 24 weeks later. The grafted tissue survived and grew in both types of recipient with a significant increase in weight and seminiferous tubule diameter. Recovery of grafts from intact recipients 24 weeks post-grafting was significantly lower than that from the castrated recipients. Seminal vesicle indices and serum testosterone levels were lower in castrated recipients at both collection time points in comparison to the intact recipients and non-grafted intact mouse controls. Pachytene spermatocytes were the most advanced germ cells observed in grafts recovered from castrated recipients 24 weeks post-grafting. Complete spermatogenesis, as indicated by the presence of elongated spermatids, was present only in grafts from intact recipients collected 24 weeks post-grafting. However, significant number of germ cells with DNA damage was also detected in these grafts as indicated by TUNEL assay. The complete germ cell differentiation in xenografts from intact recipients may be attributed to efficient Sertoli cell maturation. These results suggest that germ cell differentiation in buffalo testis xenograft can be completed by altering the recipient gonadal status.

[Effect of radio-ecological conditions in the ChNPP exclusion zone on morphofunctional state and responsiveness of organs and tissues of laboratory animals].

The state of hematopoietic, reproductive and endocrine systems of the organisms of male rats and their offspring in generations (F0-F1-F2) was studied, and the sensitivity of an organism to the action of carcinogen (Af mice) after a stay in the ChNPP exclusion zone was analyzed. It was ascertained that the most significant changes of the morphofunctional state of the animals were observed in the II generation (F2), which remained for a long period under the conditions of radioactive contamination. We have revealed an increased number of leukocytes, neutrophils, lymphocytes, and, especially, monocytes as against while the decrease in the number of erythrocytes and haemoglobin content; the decrease of thyroid function and cortical layer of the adrenals as opposed to while the increase in the relative weight of testes and their epididymides and the decrease in the number of spermatocytes and spermatozoa in the testis tissue. The exposure of Af mice in the exclusion zone increases the processes of mutagenesis and carcinogenesis, and changes the organism response to standardized action of chemical carcinogen. The increase in the exposure time of animals intensifies metabolic processes in a cell and increases their sensitivity to the action of xenobiotics.

Social cues of sperm competition influence accessory reproductive gland size in a promiscuous mammal.

Theory predicts that males should increase overall investment in ejaculate expenditure with increasing levels of sperm competition. Since ejaculate production is costly, we may expect males to tailor their reproductive investment according to anticipated levels of sperm competition. Here, we investigate plasticity in ejaculate investment in response to cues of population average levels of sperm competition in a promiscuous mammal, the bank vole (Myodes glareolus). We manipulated the social experience of experimental subjects during sexual development via differential exposure to the odour of rival males, to simulate conditions associated with relatively high or low average levels of sperm competition. Males exposed to a high level of competition developed larger major accessory reproductive glands (seminal vesicles) than those that experienced a low level of competition, suggesting that an increased investment in the production of copulatory plugs and/or mating rate may be beneficial at relatively high sperm competition levels. However, investment in sperm production, testis size and sperm motility were not altered according to social experience. Our findings emphasize the importance of non-sperm components of the ejaculate in mammalian postcopulatory sexual selection, and add to the growing evidence linking plasticity in reproductive traits to social cues of sperm competition.