Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 231
Filtrar
1.
Biochem Biophys Res Commun ; 704: 149596, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38430697

RESUMO

PHD finger protein 7 (Phf7) is a member of the PHF family proteins, which plays important roles in spermiogenesis. Phf7 is expressed in the adult testes and its deficiency causes male infertility. In this study, we tried to find the causal relationship between Phf7 deficiency and reduced growth retardation which were found in null knock-out (Phf7-/-) mice. Phf7-/- mice were born normally in the Mendelian ratio. However, the Phf7-/- males showed decreased body weight gain, bone mineral density, and bone mineral content compared to those in wild-type (WT) mice. Histological analysis for tibia revealed increased number of osteoclast cells in Phf7-/- mice compared with that in WT mice. When we analyzed the expressions for marker genes for the initial stage of osteoclastogenesis, such as receptor activator of nuclear factor kappa B (Rank) in tibia, there was no difference in the mRNA levels between Phf7-/- and WT mice. However, the expression of tartrate-resistant acid phosphatase (Trap), a mature stage marker gene, was significantly higher in Phf7-/- mice than in WT mice. In addition, the levels of testosterone and dihydrotestosterone (DHT), more potent and active form of testosterone, were significantly reduced in the testes of Phf7-/- mice compared to those in WT mice. Furthermore, testicular mRNA levels for steroidogenesis marker genes, namely Star, Cyp11a1, Cyp17a1 and 17ß-hsd, were significantly lower in Phf7-/- mice than in WT mice. In conclusion, these results suggest that Phf7 deficiency reduces the production of male sex hormones and thereby impairs associated bone remodeling.


Assuntos
Hormônios Testiculares , Animais , Masculino , Camundongos , Remodelação Óssea , Osteoclastos/metabolismo , RNA Mensageiro/metabolismo , Hormônios Testiculares/metabolismo , Testosterona/metabolismo
2.
J Trace Elem Med Biol ; 79: 127216, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37224746

RESUMO

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.


Assuntos
Hormônios Testiculares , Testículo , Ratos , Animais , Masculino , Ratos Wistar , Ginkgo biloba/metabolismo , Regulação para Baixo , Regulação para Cima , Hormônios Testiculares/metabolismo , Hormônios Testiculares/farmacologia , Chumbo/metabolismo , Antioxidantes/metabolismo , Testosterona , Estresse Oxidativo , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , Glutationa/metabolismo , Suplementos Nutricionais , Sementes/metabolismo
3.
BMC Med ; 20(1): 399, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266662

RESUMO

BACKGROUND: Reduced androgen action during early fetal development has been suggested as the origin of reproductive disorders comprised within the testicular dysgenesis syndrome (TDS). This hypothesis has been supported by studies in rats demonstrating that normal male development and adult reproductive function depend on sufficient androgen exposure during a sensitive fetal period, called the masculinization programming window (MPW). The main aim of this study was therefore to examine the effects of manipulating androgen production during different timepoints during early human fetal testis development to identify the existence and timing of a possible window of androgen sensitivity resembling the MPW in rats. METHODS: The effects of experimentally reduced androgen exposure during different periods of human fetal testis development and function were examined using an established and validated human ex vivo tissue culture model. The androgen production was reduced by treatment with ketoconazole and validated by treatment with flutamide which blocks the androgen receptor. Testicular hormone production ex vivo was measured by liquid chromatography-tandem mass spectrometry or ELISA assays, and selected protein markers were assessed by immunohistochemistry. RESULTS: Ketoconazole reduced androgen production in testes from gestational weeks (GW) 7-21, which were subsequently divided into four age groups: GW 7-10, 10-12, 12-16 and 16-21. Additionally, reduced secretion of testicular hormones INSL3, AMH and Inhibin B was observed, but only in the age groups GW 7-10 and 10-12, while a decrease in the total density of germ cells and OCT4+ gonocytes was found in the GW 7-10 age group. Flutamide treatment in specimens aged GW 7-12 did not alter androgen production, but the secretion of INSL3, AMH and Inhibin B was reduced, and a reduced number of pre-spermatogonia was observed. CONCLUSIONS: This study showed that reduced androgen action during early development affects the function and density of several cell types in the human fetal testis, with similar effects observed after ketoconazole and flutamide treatment. The effects were only observed within the GW 7-14 period-thereby indicating the presence of a window of androgen sensitivity in the human fetal testis.


Assuntos
Hormônios Testiculares , Testículo , Humanos , Masculino , Androgênios/farmacologia , Androgênios/metabolismo , Flutamida/farmacologia , Flutamida/metabolismo , Cetoconazol/metabolismo , Cetoconazol/farmacologia , Receptores Androgênicos/metabolismo , Hormônios Testiculares/metabolismo , Hormônios Testiculares/farmacologia , Testosterona/farmacologia
4.
Pathol Oncol Res ; 25(4): 1621-1626, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30721393

RESUMO

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.


Assuntos
Apoptose , Carcinogênese/patologia , Proliferação de Células , Neoplasias Colorretais/patologia , Hormônios Testiculares/metabolismo , Carcinogênese/metabolismo , Ciclo Celular , Movimento Celular , Neoplasias Colorretais/metabolismo , Humanos , Células Tumorais Cultivadas
5.
Clin Endocrinol (Oxf) ; 89(1): 85-92, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29668033

RESUMO

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.


Assuntos
Gonadotropinas/urina , Hormônio Luteinizante/metabolismo , Ovário/metabolismo , Hormônios Testiculares/metabolismo , Testículo/metabolismo , Estradiol/urina , Feminino , Hormônio Foliculoestimulante/urina , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro/metabolismo , Recém-Nascido Prematuro/urina , Inibinas/urina , Hormônio Luteinizante/urina , Masculino , Ovário/patologia , Hormônios Testiculares/urina , Testículo/patologia
6.
Gene ; 652: 7-15, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29412153

RESUMO

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.


Assuntos
Caspase 3/genética , Regulação Neoplásica da Expressão Gênica , NF-kappa B/genética , RNA Interferente Pequeno/genética , Hormônios Testiculares/genética , Neoplasias da Bexiga Urinária/terapia , Animais , Apoptose , Caspase 3/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Humanos , Camundongos , Camundongos Nus , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Análise de Sobrevida , Hormônios Testiculares/antagonistas & inibidores , Hormônios Testiculares/metabolismo , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/mortalidade , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
7.
Mol Med Rep ; 9(3): 955-60, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24366307

RESUMO

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.


Assuntos
Técnicas de Transferência de Genes , Vírus Oncogênicos/genética , Regiões Promotoras Genéticas/genética , Hormônios Testiculares/genética , Testículo/metabolismo , Animais , Feminino , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Hormônios Testiculares/metabolismo
8.
J Neuroimmunol ; 265(1-2): 20-35, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24157129

RESUMO

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.


Assuntos
Catecolaminas/metabolismo , Receptores Adrenérgicos beta/metabolismo , Transdução de Sinais/fisiologia , Hormônios Testiculares/metabolismo , Timo/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Epiteliais/metabolismo , Glutamil Aminopeptidase/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/metabolismo , Orquiectomia , Lectinas de Plantas/metabolismo , Propranolol/farmacologia , Ratos , Receptores Adrenérgicos beta/genética , Transdução de Sinais/efeitos dos fármacos , Timócitos/efeitos dos fármacos , Timócitos/metabolismo , Timo/citologia , Timo/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo
9.
PLoS One ; 8(2): e56955, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23451117

RESUMO

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.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA/fisiologia , Hormônios Testiculares/metabolismo , Animais , Células Cultivadas , Reparo do DNA/genética , Desenvolvimento Embrionário/genética , Feminino , Imunoprecipitação , Masculino , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Hormônios Testiculares/genética
10.
Reproduction ; 141(1): 37-46, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20956578

RESUMO

The testes are essential endocrine regulators of fetal masculinization and male development and are, themselves, subject to hormonal regulation during gestation. This review focuses, primarily, on this latter control of testicular function. Data available suggest that, in most mammalian species, the testis goes through a period of independent function before the fetal hypothalamic-pituitary-gonadal axis develops at around 50% of gestation. This pituitary-independent phase coincides with the most critical period of fetal masculinization. Thereafter, the fetal testes appear to become pituitary hormone-dependent, concurrent with declining Leydig cell function, but increasing Sertoli cell numbers. The two orders of mammals most commonly used for these types of studies (rodents and primates) appear to represent special cases within this general hypothesis. In terms of testicular function, rodents are born 'early' before the pituitary-dependent phase of fetal development, while the primate testis is dependent upon placental gonadotropin released during the pituitary-independent phase of development.


Assuntos
Feto/metabolismo , Hormônios/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Transdução de Sinais , Testículo/metabolismo , Animais , Animais Recém-Nascidos , Humanos , Sistema Hipotálamo-Hipofisário/embriologia , Recém-Nascido , Células Intersticiais do Testículo/metabolismo , Masculino , Hormônios Hipofisários/metabolismo , Hormônios Placentários/metabolismo , Células de Sertoli/metabolismo , Espermatozoides/metabolismo , Hormônios Testiculares/metabolismo , Testículo/embriologia
11.
Int J Androl ; 34(6 Pt 1): 624-32, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21114676

RESUMO

Mouse gametogenetin (Ggn) is a testis-enriched gene that encodes multiple spliced transcripts giving rise to three predicted protein isoforms: GGN1, GGN2 and GGN3. Of these, GGN1 has been linked to germ cell development. Based on the spatial and temporal expression pattern of GGN1 during mouse spermatogenesis, it has been proposed as a candidate human infertility gene. Here, we report the localization of GGN1 in the human testis and ovary compared with the mouse orthologue. Within the testis, GGN1 was confined to pachytene spermatocytes and spermatids. During mid-prophase GGN1 redistributes from a solely cytoplasmic localization to both cytoplasmic and nuclear in late prophase spermatocytes and round spermatids, and is ultimately incorporated into the sperm tail. Within both mouse and human ovaries, GGN1 was localized within granulosa cells. Lower levels of expression were observed in mouse oocytes and the cumulus cells. Furthermore, to define the level of sequence variation in the fertile population and to assess the potential for an association with male infertility, we sequenced the coding region of human GGN in 100 idiopathic oligospermic infertile and 100 control men. Fifteen genetic variants were identified, of which 10 had not previously been reported. No significant associations with fertility status were observed, suggesting that variance in the GGN gene are not a common cause of oligospermic infertility in Australian men.


Assuntos
Ovário/metabolismo , Hormônios Testiculares/metabolismo , Testículo/metabolismo , Sequência de Aminoácidos , Animais , Austrália , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
12.
Endocrinology ; 151(8): 4018-23, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20555023

RESUMO

The hypothalamic-pituitary-gonadal (HPG) axis is involved in both the regulation of growth of the developing testis and in controlling spermatogenic and steroidogenic activity in the adult testis. Here, we develop a novel testicular xenografting model to examine to which degree testicular growth and function are controlled by intra- and extratesticular factors. Two or eight halves of neonatal Djungarian hamster testes were implanted into intact, hemicastrated, or castrated nude mouse recipients, and the development of the grafts under reduced or increased competition of testicular tissue was monitored and analyzed. We hypothesized that the outgrowth of the testicular grafts is influenced by the total amount of testicular tissue present in a host and that less testicular tissue in a host would result in more extended outgrowth of the grafts. Our results reveal that the hypothesis is wrong, because implanted hamster testis tissue irrespectively of the grafting condition grows to a similar size revealing an intrinsic mechanism for testicular growth. In contrast, similar size of seminal vesicle as bio-indicator of androgen levels in all hosts revealed that the steroidogenic activity is independent from the mass of testicular tissue and that steroid levels are extrinsically regulated by the recipient's HPG axis. We propose that the model of testicular xenografting provides highly valuable options to explore testicular growth and endocrine regulation of the HPG axis.


Assuntos
Modelos Teóricos , Hormônios Testiculares/fisiologia , Testículo/anatomia & histologia , Testículo/crescimento & desenvolvimento , Testículo/transplante , Animais , Animais Recém-Nascidos , Peso Corporal , Células Cultivadas , Cricetinae , Sistema Endócrino/fisiologia , Masculino , Camundongos , Camundongos Nus , Orquiectomia , Tamanho do Órgão/fisiologia , Phodopus , Hormônios Testiculares/metabolismo , Testículo/fisiologia , Transplante Heterólogo
13.
Inhal Toxicol ; 21(10): 803-11, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19653803

RESUMO

We investigated the effects of nanoparticle-rich diesel exhaust (NR-DE) on reproductive function. Eight-week-old male F344 rats were divided into 12 experimental groups and exposed to either whole NR-DE at low (15.37 microg/m(3), 2.27 x 10(5) particles/cm(3)), middle (36.35 microg/m(3), 5.11 x 10(5) particles/cm(3)), or high (168.84 microg/m(3), 1.36 x 10(6) particles/cm(3)) concentrations or clean air for 4, 8, or 12 weeks (5 hours/day, 5 days/week). NR-DE exposure for 4 or 8 weeks did not affect body weight; however, body weight was significantly decreased in rats exposed to low- or high- concentration NR-DE for 12 weeks compared to the control group. Relative weights of testes, epididymides, seminal vesicles, and prostate had increased non-significantly in all NR-DE-exposed rats at 4, 8, and 12 weeks. Adrenal gland relative weights were significantly increased at 4 weeks in rats exposed to low-concentration NR-DE. Plasma luteinizing hormone and follicle stimulating hormone concentrations did not change significantly. Plasma testosterone concentrations were significantly increased after exposure to low- or middle-concentration NR-DE for 4 or 8 weeks compared to controls. Plasma immunoreactive (ir-) inhibin concentrations were significantly increased after exposure to high-concentration NR-DE for 4 weeks or middle- or high-concentration NR-DE for 12 weeks compared to controls. Testicular testosterone concentrations were significantly increased at 4, 8, and 12 weeks after exposure to low-concentration NR-DE compared to controls. In contrast, with exposure to low- or high-concentration NR-DE, testicular ir-inhibin concentrations were significantly greater than in controls, but only at 4 weeks. These results suggest that NR-DE inhalation disrupts the endocrine activity of the male reproductive system.


Assuntos
Nanopartículas/toxicidade , Hormônios Testiculares/metabolismo , Testículo/efeitos dos fármacos , Emissões de Veículos/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Radioimunoensaio , Ratos , Ratos Endogâmicos F344 , Testículo/metabolismo , Testículo/patologia
14.
Reproduction ; 135(6): 751-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18502891

RESUMO

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.


Assuntos
Glicoproteínas/análise , Cauda do Espermatozoide/química , Hormônios Testiculares/análise , Testículo/química , Acrossomo/química , Acrossomo/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting/métodos , Western Blotting/métodos , Moléculas de Adesão Celular , Clonagem Molecular , Engenharia Genética , Glicoproteínas/genética , Glicoproteínas/metabolismo , Imuno-Histoquímica , Masculino , Proteínas de Membrana , Camundongos , Dados de Sequência Molecular , Ligação Proteica , Motilidade dos Espermatozoides/fisiologia , Cauda do Espermatozoide/metabolismo , Espermátides/química , Espermátides/metabolismo , Espermatócitos/química , Espermatócitos/metabolismo , Espermatogênese/fisiologia , Hormônios Testiculares/genética , Hormônios Testiculares/metabolismo , Testículo/metabolismo , Técnicas do Sistema de Duplo-Híbrido
15.
Semin Reprod Med ; 25(5): 344-51, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17710730

RESUMO

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.


Assuntos
Envelhecimento/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Ovário/metabolismo , Reprodução/fisiologia , Hormônio Antimülleriano , Estrogênios/metabolismo , Retroalimentação Fisiológica , Feminino , Hormônio Foliculoestimulante/metabolismo , Glicoproteínas/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Inibinas/metabolismo , Hormônio Luteinizante/metabolismo , Ciclo Menstrual/metabolismo , Pós-Menopausa/metabolismo , Progesterona/metabolismo , Hormônios Testiculares/metabolismo
16.
Andrologia ; 39(3): 93-100, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17683469

RESUMO

The prenatal differentiation of male and female gonads of the mouse was investigated both morphologically and immunohistochemically. Sexual dimorphism could be detected as early as 12 days post-coitum (dpc) by the appearance of the primary elements of the tunica albuginea and positive immunoreactivity for anti-Muellerian hormone in the Sertoli cells of the male gonad. Male germ cells passed two waves of mitotic activity, a first wave between 12 and 14 dpc, which is followed by apoptosis of the old germ cell generation, and a second wave between 17 and 20 dpc. Oct-4 was expressed as a juxtanuclear ring in the cytoplasm of germ cells up to 17 dpc. Subsequently, it was down-regulated and completely disappeared in 20 dpc full-term fetuses. By contrast, M2A antigen revealed only a weak immunoreaction in some germ cells of 14 dpc gonads, but exhibited strong signals in all germ cells of 20 dpc full-term fetuses. Therefore, we postulate that, in the mouse, prenatal germ cells represent two populations: the first is immunopositive for Oct-4 and disappeared in full-term fetuses, whereas the second appeared in 14 dpc and is immunopositive for M2A antigen.


Assuntos
Diferenciação Celular/fisiologia , Ovário/embriologia , Testículo/embriologia , Animais , Hormônio Antimülleriano , Apoptose , Feminino , Células Germinativas/citologia , Glicoproteínas/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Fator 3 de Transcrição de Octâmero/metabolismo , Ovário/metabolismo , Diferenciação Sexual/fisiologia , Hormônios Testiculares/metabolismo , Testículo/metabolismo
17.
Endocrinology ; 148(8): 3704-10, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17495005

RESUMO

Testicular Leydig cells produce testosterone and provide the hormonal environment required for male virilization and spermatogenesis. In utero, fetal Leydig cells (FLCs) are necessary for the development of the Wolffian duct and male external genitalia. Steroidogenic factor 1 (Sf1) is a transcriptional regulator of hormone biosynthesis genes, thus serving a central role in the Leydig cell. Desert hedgehog (Dhh), a Sertoli cell product, specifies the FLC lineage in the primordial gonad through a paracrine signaling mechanism. Postnatally, FLCs are replaced in the testis by morphologically distinct adult Leydig cells (ALCs). To study a putative interaction between Sf1 and Dhh, we crossed Sf1 heterozygous mutant mice with Dhh homozygous null mice to test the function of these two genes in vivo. All of the compound Sf1(+/-); Dhh(-/-) mutants failed to masculinize and were externally female. However, embryonic gonads contained anastomotic testis cords with Sertoli cells and germ cells, indicating that sex reversal was not attributable to a fate switch of the early gonad. Instead, external feminization was attributable to the absence of differentiated FLCs in XY compound mutant mice. ALCs also failed to develop, suggesting either a dependence of ALCs on the prenatal establishment of Leydig cell precursors or that Sf1 and Dhh are both required for ALC maturation. In summary, this study provides genetic evidence that combinatorial expression of the paracrine factor Dhh and nuclear transcription factor Sf1 is required for Leydig cell development.


Assuntos
Proteínas Hedgehog/metabolismo , Proteínas de Homeodomínio/metabolismo , Células Intersticiais do Testículo/fisiologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Testículo/embriologia , Testículo/fisiologia , Fatores de Transcrição/metabolismo , Animais , Hormônio Antimülleriano , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Transtornos do Desenvolvimento Sexual , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Células Germinativas/citologia , Células Germinativas/fisiologia , Glicoproteínas/metabolismo , Proteínas Hedgehog/genética , Proteínas de Homeodomínio/genética , Células Intersticiais do Testículo/citologia , Masculino , Mesonefro/embriologia , Mesonefro/fisiologia , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Mitose , Gravidez , Receptores Citoplasmáticos e Nucleares/genética , Diferenciação Sexual/fisiologia , Fator Esteroidogênico 1 , Hormônios Testiculares/metabolismo , Testículo/citologia , Fatores de Transcrição/genética
18.
Toxicol Appl Pharmacol ; 221(1): 95-101, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17442358

RESUMO

The effects on the hypothalamus-pituitary-testicular axis of the well-known antispermatogenic drug lonidamine (LND) has not been elucidated so far. In the present study, the possible changes of the testicular steroid hormones were evaluated in immature mice for a better characterization of the LND adverse effects both in its use as antitumoral agent and male contraceptive. Male CD1 mice were orally treated on postnatal day 28 (PND28) with LND single doses (0 or 100 mg/kg b.w.) and euthanized every 24 h from PND29 to PND32, on PND35 and on PND42 (1 and 2 weeks after the administration, respectively). Severe testicular effects were evidenced in the LND treated groups, including: a) significant testis weight increase, 24 h and 48 h after dosing; b) sperm head counts decrease (more than 50% of the control) on PND29-32; c) damage of the tubule morphology primarily on the Sertoli cell structure and germ cell exfoliation. All these reproductive endpoints were recovered on PND42. At the same time, a significant impairment of the testicular steroid balance was observed in the treated mice, as evidenced by the decrease of testosterone (T) and androstenedione (ADIONE) and the increase of 17OH-progesterone (17OH-P4) on the first days after dosing, while the testicular content of 17beta-estradiol (E2) was unchanged. The hormonal balance was not completely restored afterwards, as levels of T, ADIONE and 17OH-P4 tended to be higher in the treated mice than in the controls, on PND35 and PND42. These data showed for the first time that LND affects intratesticular steroids in experimental animals. However further data are needed both to elucidate the mechanism responsible for the impairment of these metabolic pathways and to understand if the androgens decrease observed after LND administration could be partially involved in the testicular damage.


Assuntos
Indazóis/toxicidade , Hormônios Testiculares/metabolismo , Testículo/efeitos dos fármacos , Fatores Etários , Androstenodiona/metabolismo , Animais , Antiespermatogênicos/administração & dosagem , Antiespermatogênicos/toxicidade , Ensaio de Imunoadsorção Enzimática , Estradiol/metabolismo , Hidroxiprogesteronas/metabolismo , Indazóis/administração & dosagem , Intubação Gastrointestinal , Masculino , Camundongos , Microscopia de Polarização , Tamanho do Órgão/efeitos dos fármacos , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/patologia , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/patologia , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/patologia , Testículo/metabolismo , Testículo/patologia , Testosterona/metabolismo , Fatores de Tempo
19.
J Clin Endocrinol Metab ; 92(5): 1796-802, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17327387

RESUMO

CONTEXT: The strong relationship between serum anti-Müllerian hormone (AMH) levels and the number of antral follicles supports the use of AMH measurements as a quantitative marker of the ovarian follicular status. Yet, it still is unclear whether the aptitude of an individual follicle to produce AMH reflects its reproductive competence. OBJECTIVE: This study examined the possible relationship between serum or follicular fluid (FF) AMH concentrations and the fate of the ensuing oocytes and embryos obtained by in vitro fertilization-embryo transfer conducted in monodominant follicle cycles. DESIGN AND SETTING: We conducted a prospective study at the University of Paris XI, Assistance Publique-Hôpitaux de Paris, Institut National de la Santé et de la Recherche Médicale U782. PATIENTS: Patients included 118 infertile in vitro fertilization-embryo transfer candidates. INTERVENTIONS: Concentrations of AMH, progesterone, and estradiol were measured in the serum on cycle d 3 and on the day of oocyte pickup (dOPU), and in FF. Cycles were sorted into three sets of three distinct groups according to whether serum d 3, serum dOPU, and FF AMH concentrations were 30th centile or below (low AMH), between the 31st and the 70th centiles (average AMH), or above the 70th centile (high AMH) of measurements. MAIN OUTCOME MEASURE: Clinical pregnancy and embryo implantation rates were assessed. RESULTS: Clinical pregnancy rates (5.7, 20.0, and 39.5%, respectively; P < 0.002) and embryo implantation rates (11.8, 30.8, and 65.4, respectively; P <0.001) were markedly different among the low, moderate, and high FF AMH groups but not among the serum (d 3 or dOPU) AMH groups. Fertilization rates and embryo morphology remained similar irrespective of AMH concentrations in the serum or in FF. Incidentally, FF AMH concentrations were negatively correlated with FF progesterone (r = -0.27; P <0.003) and FF estradiol (r = -0.21; P <0.02) concentrations. CONCLUSIONS: Concentrations of AMH in the FF, but not in the serum, constitute a useful follicular marker of embryo implantation and are negatively related to FF progesterone and estradiol concentrations.


Assuntos
Implantação do Embrião/fisiologia , Embrião de Mamíferos/metabolismo , Fertilização In Vitro , Líquido Folicular/metabolismo , Fase Folicular/metabolismo , Glicoproteínas/metabolismo , Folículo Ovariano/metabolismo , Hormônios Testiculares/metabolismo , Adulto , Hormônio Antimülleriano , Estradiol/sangue , Estradiol/metabolismo , Feminino , Líquido Folicular/química , Glicoproteínas/análise , Glicoproteínas/sangue , Humanos , Modelos Logísticos , Folículo Ovariano/diagnóstico por imagem , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez , Progesterona/sangue , Progesterona/metabolismo , Hormônios Testiculares/análise , Hormônios Testiculares/sangue , Ultrassonografia
20.
Anat Histol Embryol ; 36(1): 24-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17266663

RESUMO

Anti Müllerian Hormone, AMH, is believed to be the main agent in the freemartin syndrome. Supposing an active role of freemartin gonads in AMH secretion, in the present study, we aimed at investigating the presence and the localization of AMH producing cells either in fetal or in adult freemartin gonads. Our finding of positive AMH cells in a 26-week-old freemartin fetus indicates an active role of masculinized freemartin gonads in AMH secretion. However, the positive reaction, limited to few cells grouped in 'nests' in proximity to testis cord-like structures, supports a chimeric origin of such cells, migrated from the male co-twin. No adult freemartin, irrespective from the degree of masculinization, showed any AMH positive cell.


Assuntos
Bovinos/embriologia , Freemartinismo/embriologia , Glicoproteínas/metabolismo , Hormônios Testiculares/metabolismo , Animais , Hormônio Antimülleriano , Bovinos/metabolismo , Diferenciação Celular , Feminino , Feto , Freemartinismo/metabolismo , Imuno-Histoquímica/veterinária , Masculino , Ovário/metabolismo , Gravidez , Testículo/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...