Ginkgo biloba supplement abates lead-induced endothelial and testicular dysfunction in Wistar rats via up-regulation of Bcl-2 protein expression, pituitary-testicular hormones and down-regulation of oxido-inflammatory reactions.

BACKGROUND: Apoptotic and oxido-inflammatory pathways have been found to be up-regulated in lead acetate poisoning which has been associated to endothelial and testicular dysfunctions. It is yet uncertain, nevertheless, if treatment with Ginkgo biloba supplements (GBS), a flavonoid-rich natural product can lessen the adverse effects of lead on endothelial and testicular functions. This study investigated the impact of Ginkgo biloba supplementation on lead-induced endothelial and testicular dysfunctions. METHODS: The animals were treated with GBS (50 mg/kg and 100 mg/kg orally) for 14 days following oral exposure to lead acetate (25 mg/kg) for 14 days. After euthanasia, blood samples, epididymal sperm, testes, and aorta were collected. The quantities of the hormones (testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH), as well as the anti-apoptotic, oxidative, nitrergic, inflammatory markers, were then determined using immunohistochemistry, ELISA, and conventional biochemical methods. RESULTS: GBS reduced lead-induced oxidative stress by increasing the levels of the antioxidant enzymes catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD), while lowering malondialdehyde (MDA) in endothelium and testicular cells. Normal testicular weight was restored by GBS which also decreased endothelial endothelin-I and increased nitrite levels. TNF-α and IL-6 were decreased while Bcl-2 protein expression was enhanced. Lead-induced alterations in reproductive hormones (FSH, LH, and testosterone) were also restored to normal. CONCLUSION: According to our result, using Ginkgo biloba supplement prevented lead from causing endothelial and testicular dysfunction by raising pituitary-testicular hormone levels, boosting Bcl-2 protein expression and lowering oxidative and inflammatory stress in the endothelium and testes.

GGN Promotes Tumorigenesis by Regulating Proliferation and Apoptosis in Colorectal Cancer.

Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. GGN is a germ cell-specific gene, but its function in CRC has been rarely reported to date. The aim of this study was to investigate the potential role of GGN in CRC tumorigenesis. Therefore, in this study, we examined the expression of GGN in CRC cell lines and tissues and its effects on cellular proliferation and apoptosis. We then explored the underlying mechanism. Our results showed that GGN was significantly overexpressed in both CRC cell lines and tissues. Silencing GGN robustly inhibited proliferation of CRC cells, and it also promoted apoptosis of CRC cells. Moreover, knockdown of GGN inhibited the expression of p-Akt in CRC cells. Taken together, these results showed that knockdown of GGN inhibits proliferation and promotes apoptosis of CRC cells through the PI3K/Akt signaling pathway. Our findings revealed for the first time a potential oncogenic role for GGN in CRC progress. This finding may provide a unique perspective on how a germ cell-specific gene might serve as a biomarker, or even as a therapeutic target, for CRC.

Sexual dimorphism in postnatal gonadotrophin levels in infancy reflects diverse maturation of the ovarian and testicular hormone synthesis.

BACKGROUND: The postnatal gonadotrophin surge is sexually dimorphic: FSH levels predominate in girls and LH levels in boys. However, in preterm (PT) girls, both gonadotrophin levels are higher than in PT boys. OBJECTIVE: To evaluate how gonadal maturation contributes to the sex differences in FSH and LH. DESIGN: Monthly follow-up of 58 full-term (FT, 29 boys) and 67 PT (33 boys) infants from 1 week (D7) to 6 months of age (M1-M6). Analyses were also carried out according to postmenstrual (PM) age in PT infants. METHODS: Urinary LH, FSH, oestradiol (E2), testosterone (T) and serum inhibin B (InhB) levels. RESULTS: High gonadotrophin levels in PT girls abruptly decreased (P < .001) by M2, corresponding to a PM age of 38-42 weeks, and LH levels fell below the levels found in boys. This decrease was parallel to a steep increase in E2 levels (P < .001), and, from M4 to M6, LH and E2 correlated positively in PT girls (P < .01). T levels in PT boys increased earlier than E2 levels in PT girls. In addition, InhB levels were high in PT boys already at D7, in contrast to low InhB in PT girls. InhB and FSH correlated negatively in the whole group (P < .001). CONCLUSIONS: Ovarian hormone synthesis is immature and incapable of responding to gonadotrophin stimulus before 38-42 PM weeks in PT girls, which may explain their highly elevated FSH and LH levels. The higher InhB levels in boys compared to girls may explain sexual dimorphism in FSH levels.

Increased expression of GGN promotes tumorigenesis in bladder cancer and is correlated with poor prognosis.

Bladder cancer has shown great challenge for people's life. Traditional therapeutics against bladder cancer including surgery could not bring much benefit for patients, particularly for the late stage patients. So it is necessary to keep in mind why and how bladder cancer cells survive in our body. In this study, we explored the function and the molecular mechanism of GGN gene in bladder cancer. GGN was shown to be expressed at a high level in bladder cancer tissues compared to the control and was associated with the unsatisfactory survival rate of patients. GGN was also expressed abundantly in bladder cancer cell lines such as T24, 5637 and BIU87. Then GGN was knocked down in 5637 cells and T24 cells at both RNA and protein level. In accordance, aberrant growth and proliferation were demonstrated in bladder cancer cells. The ability of migration and invasion of bladder cancer cells was also inhibited. The in vivo data further proved that the xenograft tumor growth was dramatically suppressed by GGN knockdown. Then we demonstrated that the level of IκB, bax and truncated caspase3 was upregulated after GGN was knocked down in 5637 cells. In contrast, expression level of NFκB, IKK, c-Myc, cyclin D1 and Bcl-2 was reduced. Further, the phosphorylation level of IκB was also downregulated. These data suggest that NFκB/caspase3-mediated apoptosis signaling was regulated by GGN. Conclusively, GGN played a tumor-promoting role in bladder cancer through regulation of NFκB/caspase3-mediated apoptosis signaling. This study provides a new clue for the treatment of patients with bladder cancer.

Negative effects of bisphenol A on testicular functions in albino rats and their abolitions with Tribulus terristeris L

ABSTRACT This study was conducted to find out the ameliorative properties of Tribulus terristeris L (TT) on BPA induced spermatotoxicity in male albino rats. Mature male albino rats were divided into five groups, Group A was taken as control for comparison group, whereas the other four groups namely B(vehicle control), C (toxic), D (preventive control) and Group E (amelioration group) received distilled water, olive oil, BPA, TT, and (TT + BPA) respectively. Macroscopic results revealed decreased body weight of rats, weight of testes, and the relative tissue weight index (RTWI) in BPA induced group. Hormonal (testosterone) assay results revealed the decreased values of BPA treated group. Microscopic examination of testis of BPA treated rats showed reduction in leydig cells, decreased diameter of seminiferous tubules and low values of Johnsen's scoring. Histological examination showed discontinuity and irregularity of basement membrane and sloughing of the germinal cell linage. Group E showed the body weights of rats, weight of testes, RTWI, and increased, while reduced level of testosterone, reduced number of Leydig cells, decreased diameter of seminiferous tubules and low values of Johnsen's scoring were restored near to normal. These results demonstrate that TT might be beneficial in combating the spermatotoxicity, induced by BPA.

Peri-pubertal exposure to testicular hormones organizes response to novel environments and social behaviour in adult male rats.

Previous research has shown that exposure to testicular hormones during the peri-pubertal period of life has long-term, organizational effects on adult sexual behaviour and underlying neural mechanisms in laboratory rodents. However, the organizational effects of peri-pubertal testicular hormones on other aspects of behaviour and brain function are less well understood. Here, we investigated the effects of manipulating peri-pubertal testicular hormone exposure on later behavioural responses to novel environments and on hormone receptors in various brain regions that are involved in response to novelty. Male rodents generally spend less time in the exposed areas of novel environments than females, and this sex difference emerges during the peri-pubertal period. Male Lister-hooded rats (Rattus norvegicus) were castrated either before puberty or after puberty, then tested in three novel environments (elevated plus-maze, light-dark box, open field) and in an object/social novelty task in adulthood. Androgen receptor (AR), oestrogen receptor (ER1) and corticotropin-releasing factor receptor (CRF-R2) mRNA expression were quantified in the hypothalamus, hippocampus and medial amygdala. The results showed that pre-pubertally castrated males spent more time in the exposed areas of the elevated-plus maze and light-dark box than post-pubertally castrated males, and also confirmed that peri-pubertal hormone exposure influences later response to an opposite-sex conspecific. Hormone receptor gene expression levels did not differ between pre-pubertally and post-pubertally castrated males in any of the brain regions examined. This study therefore demonstrates that testicular hormone exposure during the peri-pubertal period masculinizes later response to novel environments, although the neural mechanisms remain to be fully elucidated.

[Study on the association between maternal urinary phthalate metabolites and testicular steroid hormones in the cord blood in a Chinese population].

OBJECTIVE: The purposes of our study were to investigate the association between maternal urinary phthalate metabolites and the levels of inhibin B (INHB) and insulin-like factor 3 (INSL3) in the cord blood in a Chinese pregnant population. METHODS: Maternal urine samples in the third trimester of pregnancy of 69 participants were collected and stored, and the samples of cord blood (10 ml) were collected at delivery between June 2011 and September 2012 in a comprehensive hospital of gynecology and obstetrics in Tianjin, China.Four phthalate metabolites, monomethyl phthalate (MMP), monoethyl phthalate (MEP), monobutyl phthalate (MBP), and mono-2-ethylhexyl phthalate (MEHP) were measured in the urine samples using liquid chromatography-tandem mass spectrometry. The levels of INHB, INSL3 in the cord blood were tested by ELISA. Associations of phthalate exposure with INHB and INSL3 levels were determined by spearman correlation and multiple regression model analysis. RESULTS: The median concentrations of observed metabolites in descending order were 49.74 µg/L for MMP, 24.96 µg/L for MEHP, 19.52 µg/L for MEP and 17.73 µg/L for MBP. The median concentrations of INHB and INSL3 were 89.09 and 106.21 ng/L.Significant negative associations between INHB and MMP(ß' = -0.252), MEP(ß' = -0.363) or the sum value (∑PAEs) (ß' = -0.346) were found by the multiple regression model analysis. For INSL3, only the sum value (ß' = -0.313) was inversely significantly associated with the levels of INSL3 in the cord blood. CONCLUSIONS: Maternal urinary phthalate metabolites were associated with INHB and INSL3 in the cord blood in a Chinese population.

Production of transgenic mice expressing tumor virus A under ovarian­specific promoter 1 control using testis­mediated gene transfer.

The aim of the present study was to produce transgenic mice expressing tumor virus A (TVA) in the ovary under ovarian specific promoter 1 (OSP1) control. A transgenic mouse model was established in which TVA, an avian retroviral receptor gene driven by OSP1, was selectively expressed in the ovary. A recombinant plasmid containing TVA cDNA and an OSP1 promoter was constructed. The DNA fragment was repeatedly injected into male mouse testes at multiple sites. At 4­7, 7­10 and 10­13 weeks following the final injection, two DNA­injected male mice were mated with four wild­type female mice to produce transgenic mice. The transgenic positive rate in mouse F1 offspring was 39.69%. When the positive F1 individuals were mated with wild­type Imprinting Control Region mice (PxW) or with positive F1 individuals (PxP), the F2 individuals had a transgenic rate of 12.44%. The transgenic rates in the F1 offspring, produced following mating at the three time intervals, were 55.71 (39/70), 30.77 (4/13) and 18.75% (9/48), respectively. The transgenic rates of the F2 offspring decreased with the age of the F1 offspring, from 26.67% when PxP were mated at 6­8 weeks of age to 6.52% when PxW were mated at 5­6 months of age. The results indicate a high efficiency of gene transfer to F1 offspring using testis­mediated gene transfer (TMGT). The transgenic rate in the F2 offspring was lower than that in the F1 offspring. The results reveal that TMGT is suitable for creating transgenic animals among F1 offspring. Semi­quantitative reverse transcription-polymerase chain reaction results showed that TVA was expressed in the mice ovaries. The results demonstrate the importance of using the replication­competent avian sarcoma­leukosis virus long terminal repeat with a splice acceptor­TVA system in ovarian tumorigenesis research.

Gonadal hormone dependent developmental plasticity of catecholamine:ß2-adrenoceptor signaling complex in male rat thymus: putative implications for thymopoiesis.

The study was undertaken considering that: i) androgens affect ß2-adrenoceptor (AR)-mediated catecholamine (CA) action in many tissues; and ii) peripubertal changes in both circulating androgen and thymic CA levels are implicated in rat thymic involution. Its aims were to: i) explore putative effects of the late prepubertal orchidectomy on thymic CA:ß2-AR complex in young adult rats, and ii) delineate the direct effects of testicular hormone withdrawal on the CA:ß2-AR complex from those elicited secondarily through altered influence of this complex components on each other's availability. Upon showing that prepubertal orchidectomy augmented the efficacy of thymopoiesis through increasing the thymocyte surface density of Thy-1, whose expression is negatively regulated by ß2-AR-mediated signaling, we examined the effects of orchidectomy and 14-day-long propranolol (PROP) treatment in orchidectomized (ORX) and sham-ORX rats on thymic norepinephrine (NE) concentration and metabolism and ß2-AR expression. Orchidectomy, despite an increase in the average NE amount per thymocyte and total thymocyte NE content, diminished thymic NE concentration. This decrease reflected the diminished density of CA-synthesizing nerve fibers, CD68+ macrophages, cortical (aminopeptidase A+), and medullary (UEA-1+) thymic epithelial cells (TECs) and their CA content (probably due to lessened TH expression accompanied by increased MAO-A expression). Moreover, orchidectomy decreased the surface ß2-AR expression on thymocytes, CD68+ macrophages and OX-62+ dendritic cells, but increased its expression on the TECs. In sham-ORX rats, PROP reduced thymic NE concentration by diminishing TH expression in the thymic cells. Additionally, PROP in thymocytes and thymic stromal cells diminished and enhanced the ß2-AR mRNA expression, respectively. However, in ORX rats PROP did not significantly affect CA(NE):ß2-AR complex components. This indicated that prepubertal orchidectomy affects ability of young adult rats to respond to ß-AR blockade by altering thymic NE and ß2-AR availability. Collectively, the results showed that testicular hormones contribute to alterations in thymus/thymopoiesis during the critical peripubertal period by shaping modulatory sympathetic influence and CA autocrine/paracrine action within the organ.

Loss of GGN leads to pre-implantation embryonic lethality and compromised male meiotic DNA double strand break repair in the mouse.

The integrity of male germ cell genome is critical for the correct progression of spermatogenesis, successful fertilization, and proper development of the offspring. Several DNA repair pathways exist in male germ cells. However, unlike somatic cells, key components of such pathways remain largely unidentified. Gametogenetin (GGN) is a testis-enriched protein that has been shown to bind to the DNA repair protein FANCL via yeast-two-hybrid assays. This finding and its testis-enriched expression pattern raise the possibility that GGN plays a role in DNA repair during spermatogenesis. Herein we demonstrated that the largest isoform GGN1 interacted with components of DNA repair machinery in the mouse testis. In addition to FANCL, GGN1 interacted with the critical component of the Fanconi Anemia (FA) pathway FANCD2 and a downstream component of the BRCA pathway, BRCC36. To define the physiological function of GGN, we generated a Ggn null mouse line. A complete loss of GGN resulted in embryonic lethality at the very earliest period of pre-implantation development, with no viable blastocysts observed. This finding was consistent with the observation that Ggn mRNA was also expressed in lower levels in the oocyte and pre-implantation embryos. Moreover, pachytene spermatocytes of the Ggn heterozygous knockout mice showed an increased incidence of unrepaired DNA double strand breaks (DSBs). Together, our results suggest that GGN plays a role in male meiotic DSB repair and is absolutely required for the survival of pre-implantation embryos.

Members of the murine Pate family are predominantly expressed in the epididymis in a segment-specific fashion and regulated by androgens and other testicular factors.

BACKGROUND: Spermatozoa leaving the testis are not able to fertilize the egg in vivo. They must undergo further maturation in the epididymis. Proteins secreted to the epididymal lumen by the epithelial cells interact with the spermatozoa and enable these maturational changes, and are responsible for proper storage conditions before ejaculation. The present study was carried out in order to characterize the expression of a novel Pate (prostate and testis expression) gene family, coding for secreted cysteine-rich proteins, in the epididymis. METHODS: Murine genome databases were searched and sequence comparisons were performed to identify members of the Pate gene family, and their expression profiles in several mouse tissues were characterized by RT-PCR. Alternate transcripts were identified by RT-PCR, sequencing and Northern hybridization. Also, to study the regulation of expression of Pate family genes by the testis, quantitative (q) RT-PCR analyses were performed to compare gene expression levels in the epididymides of intact mice, gonadectomized mice, and gonadectomized mice under testosterone replacement treatment. RESULTS: A revised family tree of Pate genes is presented, including a previously uncharacterized Pate gene named Pate-X, and the data revealed that Acrv1 and Sslp1 should also be considered as members of the Pate family. Alternate splicing was observed for Pate-X, Pate-C and Pate-M. All the Pate genes studied are predominantly expressed in the epididymis, whereas expression in the testis and prostate is notably lower. Loss of androgens and/or testicular luminal factors was observed to affect the epididymal expression of several Pate genes. CONCLUSIONS: We have characterized a gene cluster consisting of at least 14 expressed Pate gene members, including Acrv1, Sslp1 and a previously uncharacterized gene which we named Pate-X. The genes code for putatively secreted, cysteine-rich proteins with a TFP/Ly-6/uPAR domain. Members of the Pate gene cluster characterized are predominantly expressed in the murine epididymis, not in the testis or prostate, and are regulated by testicular factors. Similar proteins are present in venoms of several reptiles, and they are thought to mediate their effects by regulating certain ion channels, and are thus expected to have a clinical relevance in sperm maturation and epididymal infections.

Antimüllerian hormone (AMH) not only a marker for prediction of ovarian reserve.

The main characteristics of the Antimüllerian hormone from the points of view of biochemistry, molecular genetics, physiological functions and importance for diagnostics in reproductive endocrinology and related biomedical fields are reviewed. The role of the hormone in male and female development, its participation in oocyte maturation including selection of a dominant follicle are summarized, as well as its changes under various pathological situations in both sexes. The physiological changes of serum AMH leves in the life span in both sexes and their alterations under various pathological conditions are provided, too.

Influence of gonadal hormones on endocrine activity of gonadotroph cells in the adenohypophysis of male lambs during the postnatal transition to puberty.

Using histomorphological and functional criteria we describe the feedback mechanisms which could play a role in the regulation of the gonadotrophic axis during the postnatal transition to puberty in male lambs. The working hypothesis was that the testicular factors change the peripheral levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) by influencing the synthesis rate and storage of LH and FSH in adenohypophyseal gonadotroph cells of weanling and weaned pubertal lambs. The examination was made in (i) 9-week-old infantiles, suckling lambs undergoing weaning, testis-intact (TEI) and orchidectomised (ORCHX) at the 6th week of age, and (ii) 16-week-old pubertal lambs TEI and ORCHX at the 12th week of age (n=5 per group). Changes in gonadotrophs were assayed with hybridohistochemistry, immunohistochemistry and radioimmunoassay. The percentage of the adenohypophyseal area (PA) occupied by cells containing LHß-mRNA and FSHß-mRNA and peripheral levels of both gonadotrophins were lower (P<0.01) in the 16-week-old TEI lambs in comparison with the 9-week-old ones. The PA occupied by cells immunoreactive for LHß was lower (P<0.01), whereas in the case of FSH was greater (P<0.001) in the 16-week-old lambs. After orchidectomy the PA occupied by gonadotrophs stained for LHß-mRNA was greater (P<0.01) in 16-week-old lambs. The PA occupied by LHß-labelled cells was lower (P<0.05) in the 9-week-old ORCHX lambs, whereas in 16-week-old ones was higher (P<0.05) in comparison with the TEI lambs. The circulating LH was greater (P<0.01) in the ORCHX 9- and 16-week-old lambs compared to the TEI ones. The PA occupied by cells containing FSHß-mRNA and the plasma FSH concentration were greater (P<0.001) after orchidectomy in lambs from both age stages. The PA occupied by FSHß-labelled cells was greater (P<0.01) in the 9-week-old ORCHX lambs, whereas in 16-week-old ones was lower (P<0.05) compared to the lambs from TEI groups. In conclusion, in infantile lambs testicular factors may play inhibitory role in regulating FSH synthesis rate, storage and release in contrast to the stimulatory role in regulating LH storage reflected by the inhibitory role in regulating LH release. In lambs at the beginning of puberty, testicular factors may play inhibitory role in regulating LH synthesis rate, storage and release in contrast to the stimulatory role in regulating FSH storage reflected by the inhibitory role in regulating FSH synthesis rate and release. The effects of testicular hormones on the gonadotrophin storage, i.e. releasable pools in adenohypophyseal cells, are specific for both LH and FSH in lambs during the postnatal transition to puberty. Thus, the initiation of puberty in male sheep is a function of change of the inhibitory role of gonadal factors in regulating FSH storage to the stimulatory one and the stimulatory role of gonadal factors in regulating LH storage to the inhibitory one.

p-MAPK1/3 and DUSP6 regulate epididymal cell proliferation and survival in a region-specific manner in mice.

A fully developed, functional epididymis is important for male fertility. In particular, it is apparent that without the most proximal region, the initial segment (IS), infertility results. Therefore, it is important to understand the development and regulation of this crucial epididymal region. We have previously shown that many functions of the IS are regulated by luminal fluid factors/lumicrine factors from the testis. This study provides evidence that lumicrine factors activated the ERK pathway only in epithelial cells of the IS from Postnatal Day (P) 14 to P19 and sustained this activation into adulthood. The activated ERK pathway promoted cell proliferation and differentiation in the developing IS, although in the adult, its role was switched to maintain cell survival. To understand further the regulation of cell proliferation in the IS, we examined the role of DUSP6, an MAPK1/3 (ERK1/2) preferred phosphatase that is also regulated by lumicrine factors in the IS. Utilizing Dusp6(-/-) mice, our studies, surprisingly, revealed that Dusp6 was a major regulator of cell proliferation in the caput and corpus regions, whereas components of the ERK pathway, together with PTEN and SRC, were the major regulators of cell proliferation in the IS. We hypothesize that region-specific regulation of cell proliferation is caused by differences in the balance of activities between pro- and antiproliferation signaling pathway components for each epididymal region. An understanding of the mechanisms of cell proliferation may provide clues as to why the epididymis rarely succumbs to cancer.

Late hormonal function after testicular torsion.

INTRODUCTION: Testicular torsion may be an important cause of male infertility. We aimed to investigate the late hormonal function in patients with testicular ischemia/reperfusion injury of the testis after orchidectomy or detorsion. METHODS: Twenty patients (mean age, 13.6 years) were prospectively evaluated at a mean of 5 years after testicular torsion. The serum follicle-stimulating hormone, luteinizing hormone (before and after gonadotropin-releasing hormone stimulation), testosterone, and inhibin B were measured. Fifteen age-matched adolescents without evidence of endocrine disease were used as controls for inhibin B values. Data are quoted as mean +/- SEM. RESULTS: Twelve patients were treated with detorsion and orchidopexy, and 8 underwent orchidectomy. Serum follicle-stimulating hormone, luteinizing hormone, and testosterone were all within the reference range. Inhibin B levels were significantly reduced in the 2 groups compared with the controls (34.5 +/- 5.2 vs 63.9 +/- 12.8 pg/mL, P = .02), but were not significantly different between the orchidectomy group and the group that underwent detorsion (41.3 +/- 9.7 vs 30.4 +/- 5.9 pg/mL, P = .41). CONCLUSION: Hormonal testicular function can be compromised after testicular torsion, although the type of surgery (orchidectomy or orchidopexy) does not seem to change the effect of this ischemia/reperfusion injury.

Effects of maternal exposure to low doses of DES on testicular steroidogenesis and spermatogenesis in male rat offspring.

Our previous studies have demonstrated that prenatally administered diethylstilbestrol (DES) impairs testicular endocrine function in male offspring. The present study examined whether maternal DES treatment influences testicular steroidogenesis and spermatogenesis. DES was injected subcutaneously at 0.5 or 1.5 microg/kg/day (DES 0.5 and 1.5 groups, respectively) into pregnant SD rats on days 7-21 of gestation. Male offspring in the DES 0.5 and 1.5 groups were autopsied at 1, 3, 6 and 15 weeks after birth. At 1 week, DES treatment did not lead to a change in the volume of P450scc-positive cells (Leydig cells), suggesting that DES has no inhibitory effect on the development of Leydig cells. DES administration disrupted luteinizing hormone receptor (LHr) expression and exerted inhibitory effects on signal transduction from LHr to steroidogenic acute regulatory protein (StAR) in testicular steroidogenesis (P<0.05), although there were no changes in the mRNA expression levels of steroidogenic enzymes, such as P450scc, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and P450(17 alpha), which may have caused a decrease in the plasma testosterone level. DES treatment did not disrupt the cycle of spermatogenesis but did upregulate the expression levels of androgen receptor (AR) mRNA in both DES groups at 15 weeks (P<0.05). These results indicate that maternal DES treatment disrupts steroidogenesis but induces a high level of AR mRNA expression to counteract the low levels of testosterone during spermatogenesis.

Characterization of gametogenetin 1 (GGN1) and its potential role in male fertility through the interaction with the ion channel regulator, cysteine-rich secretory protein 2 (CRISP2) in the sperm tail.

Cysteine-rich secretory protein 2 (CRISP2) is a testis-enriched protein localized to the sperm acrosome and tail. CRISP2 has been proposed to play a critical role in spermatogenesis and male fertility, although the precise function(s) of CRISP2 remains to be determined. Recent data have shown that the CRISP domain of the mouse CRISP2 has the ability to regulate Ca(2+) flow through ryanodine receptors (RyR) and to bind to MAP kinase kinase kinase 11 (MAP3K11). To further define the biochemical pathways within which CRISP2 is involved, we screened an adult mouse testis cDNA library using a yeast two-hybrid assay to identify CRISP2 interacting partners. One of the most frequently identified CRISP2-binding proteins was gametogenetin 1 (GGN1). Interactions occur between the ion channel regulatory region within the CRISP2 CRISP domain and the carboxyl-most 158 amino acids of GGN1. CRISP2 does not bind to the GGN2 or GGN3 isoforms. Furthermore, we showed that Ggn1 is a testis-enriched mRNA and the protein first appeared in late pachytene spermatocytes and was up-regulated in round spermatids before being incorporated into the principal piece of the sperm tail where it co-localized with CRISP2. These data along with data on RyR and MAP3K11 binding define the CRISP2 CRISP domain as a protein interaction motif and suggest a role for the GGN1-CRISP2 complex in sperm tail development and/or motility.

Neuroendocrine changes with reproductive aging in women.

Aging has dramatic effects on the reproductive system in women. Undoubtedly, the most notable changes in the neuroendocrine axis arise from the loss of ovarian function, and thus, the loss of negative feedback on the hypothalamus and pituitary. Progressive decreases in inhibin B and inhibin A result in an early increase in follicle-stimulating hormone (FSH), which initially maintains folliculogenesis and estradiol secretion. Over time, regular ovulatory cycles give way to inconsistent folliculogenesis and ovulation, dramatic swings in estradiol and gonadotropin levels, and markedly irregular cycles. Changes in estrogen positive feedback may contribute to cycle disruption. Studies in younger and older postmenopausal women indicate that changes in the neuroendocrine axis occur with aging that are independent of the changing ovarian hormonal milieu of the menopausal transition. Luteinizing hormone and FSH decrease progressively after the menopause, as does gonadotropin-releasing hormone (GnRH) pulse frequency. However, the overall amount of GnRH increases with aging, consistent with a significant degree of adaptability in the aging brain in women, and suggesting that aging alters pituitary responsiveness to GnRH. Estrogen negative feedback is not altered by aging; studies of the effects of aging on estrogen positive feedback are ongoing.

Loss of ovarian reserve after uterine artery embolization: a randomized comparison with hysterectomy.

BACKGROUND: Ovarian failure as a complication of uterine artery embolization (UAE) for symptomatic uterine fibroids has raised concerns about this new treatment modality. METHODS: We investigated the occurrence of ovarian reserve reduction in a randomized trial comparing UAE and hysterectomy by measuring follicle stimulating hormone (FSH) and anti-Mullerian hormone (AMH). A total of 177 pre-menopausal women with menorrhagia due to uterine fibroids were included (UAE:n=88; hysterectomy:n=89). FSH and AMH were measured at baseline and at several time-points during the 24 months follow-up period. Follow-up AMH levels were also compared to the expected decrease due to ovarian ageing during the observational period. RESULTS: FSH increased significantly compared to baseline in both groups after 24 months follow-up (within group analysis: UAE:+12.1; P=0.001; hysterectomy:+16.3; P<0.0001). No differences in FSH values between the groups were found (P=0.32). At 24 months after treatment the number of patients with FSH levels>40 IU/l was 14/80 in the UAE group and 17/73 in the hysterectomy group (relative risk=0.75; P=0.37). AMH was measured in 63 patients (UAE: n=30; hysterectomy: n=33). After treatment AMH levels remained significantly decreased during the entire follow-up period only in the UAE group compared to the expected AMH decrease due to ageing. No differences were observed between the groups. CONCLUSIONS: This study shows that both UAE and hysterectomy affect ovarian reserve. This results in older women becoming menopausal after the intervention. Therefore, the application of UAE in women who still wish to conceive should only be considered after appropriate counselling.

Mullerian Inhibiting Substance is an ovarian growth factor of emerging clinical significance.

OBJECTIVE: To examine Mullerian Inhibiting Substance (MIS) as an emerging diagnostic marker of ovarian function. DESIGN: Medline review of published studies pertaining to the role of MIS in assessing ovarian aging, predicting response to ovulation induction in preparation for in vitro fertilization, assessing risk of developing ovarian hyperstimulation (OHSS) before ovulation induction, and diagnosis of polycystic ovarian disease (PCOS). RESULT(S): The majority of published studies to date support a role for MIS as a marker of ovarian reserve. Specific cut-off values are dependent upon the particular assay used. Mullerian Inhibiting Substance may offer value in assessing risk of OHSS and diagnosis of PCOS. CONCLUSION(S): Potential advantages of MIS compared with other conventional markers of ovarian reserve include: 1) MIS is the earliest marker to change with age; 2) it has the least intercycle variability; 3) it has the least intracycle variability; and 4) it may be informative if randomly obtained during the cycle. Widespread clinical use of MIS may await the availability of an international standard for MIS so that results using different assays may be reliably compared.