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1.
Biol Pharm Bull ; 43(11): 1687-1692, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132313

RESUMO

Several studies show that maternal conventional cigarette smoking during pregnancy has been associated with reduced sperm concentration in sons. The development of heat-not-burn (HnB) tobacco has gained a growing following. However, the effects of prenatal HnB tobacco smoking on male offspring are as yet unknown. Pregnant CD-1 mice were exposed to I-Quit-Ordinary-Smoking (IQOS) (HnB tobacco) aerosol from heat sticks, mainstream smoke from 3R4F (conventional cigarettes) or clean air, using a whole-body exposure system. Adult male offspring mice were divided into six groups: control (5- and 15-weeks-old offspring), IQOS (5 and 15-weeks-old) and 3R4F (5 and 15-weeks-old). Spermatogenesis, sperm characteristics, serum testosterone, and seminiferous tubule morphology were evaluated. Prenatal IQOS exposure increased abnormal seminiferous tubule morphology and decreased sperm production at 5 weeks, but 3R4F exposure did not. Prenatal exposure to IQOS aerosol delays sexual maturation of male offspring or adversely affects the male testicular function of the offspring more than smoke from a combustion cigarette.


Assuntos
Nicotiana/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Túbulos Seminíferos/anormalidades , Produtos do Tabaco/toxicidade , Fumar Tabaco/efeitos adversos , Aerossóis , Animais , Modelos Animais de Doenças , Feminino , Temperatura Alta , Humanos , Masculino , Exposição Materna/efeitos adversos , Camundongos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/patologia , Túbulos Seminíferos/efeitos dos fármacos , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Testosterona/sangue , Nicotiana/química
2.
FASEB J ; 33(8): 9075-9086, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31084574

RESUMO

As the major somatic cell type, Sertoli cells undergo active proliferation and play essential roles to establish testis cord at fetal stage. They also function to maintain germ cell development throughout the life of testicular development. However, the significance of Sertoli cell number for testis cord development and gonocyte fate is still unclear. Nuclear protein ataxia-telangiectasia (NPAT, also known as p220), a substrate of cyclin E/cyclin-dependent kinase 2, is well known as a regulator of cell proliferation through regulating histone expression. To study the role of NPAT during Sertoli cell development, we generated a mouse strain carrying conditional floxed Npat alleles, when crossing with anti-Müllerian hormone-cre, leading to the specific deletion of Npat in Sertoli cells. Npat disruption in Sertoli cells inhibited the programmed proliferation of fetal Sertoli cells resulting in disruption of developing testis cords, and subsequent postnatal mutant testes were severely hypoplastic. Germ cells, which are presumed to be in quiescent status during perinatal stage, exited G0 phase arrest and re-enter mitotic cell cycle prematurely. Of particular note, some germ cells possessed the meiotic signal in Npat-deficient testes. Our data thus indicates that the function of Npat-dependent Sertoli cells is essential at multiple steps in testis development, and this study also identifies Sertoli cells as a major regulator of germ cell development, which are required to maintain a local growth niche to repress premature mitosis and meiosis of gonocytes.-Jiang, X., Yin, S., Fan, S., Bao, J., Jiao, Y., Ali, A., Iqbal, F., Xu, J., Zhang, Y., Shi, Q. Npat-dependent programmed Sertoli cell proliferation is indispensable for testis cord development and germ cell mitotic arrest.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Nucleares/metabolismo , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Testículo/embriologia , Testículo/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Proliferação de Células/genética , Proliferação de Células/fisiologia , Feminino , Masculino , Meiose/genética , Meiose/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitose/genética , Mitose/fisiologia , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Gravidez , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/embriologia , Túbulos Seminíferos/metabolismo , Espermatogênese/genética , Espermatogênese/fisiologia , Espermatozoides/citologia , Espermatozoides/metabolismo , Testículo/citologia
3.
Urology ; 116: 176-179, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29548867

RESUMO

Hermaphroditism is known as ovotesticular disorder of sex development. A 14-year-old boy was admitted with right acute scrotum. Exploration revealed tunica rupture and hematoma, with no viable tissue. After 1 month, he was admitted again with left hemiscrotal pain. Microscopic examination of the left gonad demonstrated foci of hemorrhagic cysts, primordial follicles, and regions of seminiferous tubules. We preserved a testicular tissue and the ovarian part was extracted completely. Long-term follow-up with his hormonal profile is reported. This is a case of ovotesticular disorder presented with acute scrotum and we also tried to reduce long-term hormone therapy, with preservation of testicular part.


Assuntos
Dor Aguda/diagnóstico , Folículo Ovariano/cirurgia , Transtornos Ovotesticulares do Desenvolvimento Sexual/diagnóstico , Escroto/fisiopatologia , Dor Aguda/etiologia , Adolescente , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Folículo Ovariano/anormalidades , Transtornos Ovotesticulares do Desenvolvimento Sexual/complicações , Transtornos Ovotesticulares do Desenvolvimento Sexual/cirurgia , Escroto/cirurgia , Túbulos Seminíferos/anormalidades
4.
Dev Growth Differ ; 58(7): 600-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27385512

RESUMO

Zfp318, a mouse gene with a Cys2/His2 zinc finger motif, is mainly expressed in germ cells in the testis. It encodes two alternative transcripts, which regulate androgen receptor-mediated transcriptional activation or repression by overexpression of them. However, the role of Zfp318 is still obscure in vivo, especially in spermatogenesis. To elucidate the role of Zfp318 during gamete production, we established a knockout mouse line. Zfp318-null male mice exhibited infertility, whereas Zfp318-null female mice displayed normal fertility. ZFP318 was expressed during multiple stages of spermatogenesis, from spermatocytes to round spermatids. The nuclei of secondary spermatocytes showed high levels of expression. Histological analysis and quantitative analysis of DNA content showed decreased numbers of both spermatids in the seminiferous tubules and mature spermatozoa in the epididymides of Zfp318-null mice. These results suggest that Zfp318 is expressed as a functional protein in testicular germ cells and plays an important role in meiosis during spermatogenesis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Infertilidade Masculina/genética , Meiose/genética , Espermatogênese/genética , Dedos de Zinco , Animais , Proteínas de Ligação a DNA/genética , Feminino , Infertilidade Masculina/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/metabolismo , Espermátides/metabolismo , Espermátides/patologia , Espermatócitos/metabolismo , Espermatócitos/patologia
5.
Am J Clin Pathol ; 136(6): 872-80, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22095372

RESUMO

Of patients with cryptorchidism, 5% have no palpable gonad. Physical examination or scrotal exploration demonstrates tissue nubbins or small nodules that constitute the vanishing testis syndrome. At the University of Chicago Hospitals (Chicago, IL; 2004-2008), 30 surgical pathology specimens from 29 patients with this clinical diagnosis underwent scrotal exploration. Histologic and immunohistochemical comparison was done with 7 fetal testes, 8 surgically removed nonneoplastic testes, and 2 cryptorchid testes. Routine histologic studies showed no seminiferous tubules in 18 cases (60%), fibrosis in all (100%), calcifications in 16 (53%), and hemosiderin deposits in 9 (30%). In 12 cases with seminiferous tubules (40%), there were Sertoli cells only. Scrotal exploration in such cases is clinically driven and results in the removal of any tissue present. Although published studies suggest the risk for future tumor development is low, possibly absent, the definitive removal of a testicle is established by an awareness of the histologic spectrum exhibited by testicular remnants.


Assuntos
Criptorquidismo/patologia , Testículo/patologia , Adolescente , Criança , Pré-Escolar , Criptorquidismo/cirurgia , Células Germinativas , Humanos , Lactente , Masculino , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/citologia , Túbulos Seminíferos/patologia , Testículo/embriologia , Testículo/cirurgia
6.
Anat Rec (Hoboken) ; 292(4): 595-603, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19301269

RESUMO

We have recently shown that Lgr4 knock-out (LGR4KO) male mice are infertile due to a developmental defect of the reproductive tract. Spermatozoa do not reach the epididymis and accumulate at the rete testis and efferent ducts (ED). We have proposed that in LGR4KO, ED might fail to connect resulting in blind-ended tubes that preclude the normal transit of sperm cells. To explore this possibility, we reconstructed the three-dimensional (3D) structure of the organ from serial microphotographs. The resulting model allowed to individualize and follow each ED from the testis up to the epididymis, and to display the spatial distribution of their content. The transit of spermatozoa is indeed blocked in LGR4KO mice but, contrary to the expectation, the ducts connect normally to each other, forming a single tube that flows into the epididymis, as in the wild-type animals. In the KO however, transit of the sperm is abruptly blocked at the same level syncytial-like aggregates appear in the luminal space. The model also allowed calculating, for the first time, morphometric parameters of the mouse ED, such as total volume, surface, radius, and length. These data unambiguously showed that ED in the mutant mouse are dramatically shortened and less convoluted than in the wild-type animal, providing an explanation to the phenotype observed in LGR4KO. Combined with in situ immunodetection or RNA in situ hybridization, 3D reconstruction of serial histological sections will provide an efficient mean to study expression profiles in organs which do not lend themselves to whole-mount studies.


Assuntos
Receptores Acoplados a Proteínas G/genética , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/citologia , Espermatogênese/genética , Testículo/anormalidades , Testículo/citologia , Animais , Epididimo/anormalidades , Epididimo/citologia , Epididimo/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Infertilidade Masculina/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Modelos Anatômicos , Túbulos Seminíferos/metabolismo , Espermatozoides/citologia , Espermatozoides/fisiologia , Testículo/metabolismo
7.
Basic Clin Pharmacol Toxicol ; 99(2): 128-32, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16918713

RESUMO

Prenatal or early postnatal exposure to some synthetic chemicals may affect the later reproductive system of the offspring. There may also be unique responses observed due to exposure to combinations of chemicals that are not observed when the chemicals are present individually. 1,1-Dichloro-2,2 bis (p-chlorophenyl) ethylene (p,p'-DDE) is a persistent metabolite of DDT and tributyltin (TBT) compounds are used primarily as antifouling agents, as they exert biocidal actions. p,p'-DDE and TBT are ubiquitously distributed in the environment. Oral p,p'-DDE and TBT intake through marine products is demonstrated to be high in Japan. Consequently, the foetus and neonate are supposed to be exposed much more to p,p'-DDE and TBT via the maternal body. Therefore, effects of perinatal exposure to p,p'-DDE and/or TBT on the reproductive system after maturation have been investigated in rat male offspring of dams orally administered 125 ppm p,p'-DDE (approximately 10 mg/kg) and 25 ppm TBT (approximately 2 mg/kg) during the gestational and lactational period. In this study, growth retardation attributed to TBT has sustained in rat male offspring after perinatal exposure. However, perinatal exposure to p,p'-DDE and TBT failed to affect the male reproductive organs and sperm parameters in matured male offspring.


Assuntos
Diclorodifenil Dicloroetileno/toxicidade , Genitália Masculina/efeitos dos fármacos , Exposição Materna , Compostos de Trialquitina/toxicidade , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Diclorodifenil Dicloroetileno/administração & dosagem , Feminino , Hormônio Foliculoestimulante/sangue , Genitália Masculina/anormalidades , Transtornos do Crescimento/induzido quimicamente , Inseticidas/administração & dosagem , Inseticidas/toxicidade , Hormônio Luteinizante/sangue , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Distribuição Aleatória , Ratos , Ratos Wistar , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/efeitos dos fármacos , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/anormalidades , Espermatozoides/efeitos dos fármacos , Testosterona/sangue , Compostos de Trialquitina/administração & dosagem
8.
Endocrinology ; 146(2): 613-23, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15539561

RESUMO

Fetal exposure of male rats to di (n-butyl) phthalate (DBP) induces testicular changes remarkably similar to testicular dysgenesis syndrome in humans; these include induction of focal areas of dysgenetic tubules in otherwise normal testes. In searching for the fetal origins of the latter, we used image analysis to show that exposure to 500 mg/kg DBP [embryonic day (E)13.5-20.5)] caused abnormal aggregation of Leydig cells centrally in the fetal testis. This aggregation was not due to increase in Leydig cell number, and Leydig cell size was significantly reduced in DBP-exposed animals, as were testosterone levels and immunoexpression of P450 side-chain cleavage enzyme. The Leydig cell aggregates did not exhibit evidence of focal proliferation at E17.5-19.5. Using confocal microscopy and Leydig (3beta-hydroxysteroid dehydrogenase) and Sertoli (anti-Mullerian hormone) cell-specific markers, we show that fetal Leydig cell aggregates in DBP-exposed animals trap isolated Sertoli cells within them at E21.5. These areas of intermingled cells are still apparent on postnatal d 4, after cessation of DBP treatment, when they may form misshapen seminiferous cords that trap (intratubular) Leydig cells within them. These centrally located dysgenetic tubules contain germ cells in early puberty, but by adulthood they are Sertoli cell only, implying that presence of intratubular Leydig cells interferes with spermatogenesis. It is concluded that DBP-induced fetal Leydig cell aggregation may be a key event in formation of focal dysgenetic areas in the testis, and identification of the mechanisms underlying these events may give new insights into the fetal origins of testicular dysgenesis syndrome disorders in the human.


Assuntos
Anormalidades Induzidas por Medicamentos/patologia , Antagonistas de Androgênios/toxicidade , Dibutilftalato/toxicidade , Células Intersticiais do Testículo/patologia , Túbulos Seminíferos/anormalidades , Animais , Agregação Celular/efeitos dos fármacos , Feminino , Hiperplasia , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Túbulos Seminíferos/patologia
9.
Biol Reprod ; 71(1): 104-16, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14985244

RESUMO

The hypogonadic rat is characterized by male sterility, reduced female fertility, and renal hypoplasia controlled by a single recessive allele (hgn) on chromosome 10. Plasma testosterone is low and levels of gonadotropins are high in adult male hgn/hgn rats, indicating that the cause of hypogonadism lies within the testis itself. We found that the postnatal growth of the seminiferous tubules was severely affected. Here we describe the details of postnatal testicular pathogenesis of the hgn/ hgn rats. In these rats, gonadal sex determination and initial differentiation of each type of testicular cell occur, but proliferation, differentiation, and maturation of these cells during postnatal testicular development is severely affected. Postnatal pathological changes include reduced proliferation and apoptotic cell death of Sertoli cells, abnormal mitosis and cell death of gonocytes, reduced deposition of extracellular matrix proteins into the basal lamina, lack of the formation of an outer basal lamina, formation of multiple layers of undifferentiated peritubular cells, and the delayed appearance and islet conformation of adult-type Leydig cells. Apoptotic cell death of Sertoli cells and disappearance of FSH receptor mRNA expression indicate that this mutant rat is a useful model for Sertoli cell dysfunction. The abnormalities listed above might be caused by defective interactions between Sertoli cells and other types of testicular cells. Because the results presented here strongly indicate that a normal allele for hgn encodes a factor playing a critical role in testicular development, the determination of the gene responsible for hgn and the analysis of early alterations of gene expression caused by mutations in this gene would provide important information on the mechanisms of testicular development.


Assuntos
Anormalidades Múltiplas/etiologia , Hipogonadismo/complicações , Hipogonadismo/genética , Túbulos Seminíferos/anormalidades , Testículo/anormalidades , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Apoptose , Contagem de Células , Divisão Celular , Proteínas do Citoesqueleto/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Histocitoquímica , Hipogonadismo/metabolismo , Hipogonadismo/patologia , Hipogonadismo/fisiopatologia , Imuno-Histoquímica , Masculino , Ratos , Ratos Mutantes , Receptores do FSH/metabolismo , Túbulos Seminíferos/metabolismo , Túbulos Seminíferos/patologia , Coloração e Rotulagem , Testículo/metabolismo , Testículo/patologia , Distribuição Tecidual
10.
Hum Reprod ; 18(7): 1383-94, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12832361

RESUMO

BACKGROUND: The disorders comprising human 'testicular dysgenesis syndrome' (TDS) may be increasing in incidence. TDS originates in fetal life but the mechanisms are not known, and discerning them requires an animal model. METHODS AND RESULTS: The study investigated whether male rats exposed in utero to dibutyl phthalate [DBP; 500 mg/kg on gestational days (GD) 13-21] would provide a suitable model for human TDS. DBP induced a high rate (>60%) of cryptorchidism (mainly unilateral), hypospadias, infertility and testis abnormalities, similar to those in human TDS. Cell-specific immunohistochemistry and confocal microscopy were used to track development of Sertoli [anti-Müllerian hormone (AMH), Wilm's tumour (WT-1) protein, p27(kip)], Leydig [3beta-hydroxysteroid dehydrogenase (3beta-HSD)], germ (DAZL protein) and peritubular myoid (smooth muscle actin) cells from fetal life to adulthood. In scrotal and cryptorchid testes of DBP-exposed males, areas of focal dysgenesis were found that contained Sertoli and Leydig cells, and gonocytes and partially formed testicular cords; these dysgenetic areas were associated with Leydig cell hyperplasia at all ages. Suppression ( approximately 90%) of testicular testosterone levels on GD 19 in DBP-exposed males, coincident with delayed peritubular myoid cell differentiation, may have contributed to the dysgenesis. Double immunohistochemistry using WT-1 (expressed in all Sertoli cells) and p27(kip) (expressed only in mature Sertoli cells) revealed immature Sertoli cells in dysgenetic areas. DBP-exposed animals also exhibited Sertoli cell-only (SCO) tubules, sporadically in scrotal and predominantly in cryptorchid, testes, or foci of SCO within normal tubules in scrotal testes. In all SCO areas the Sertoli cells were immature. Intratubular Leydig cells were evident in DBP-exposed animals and, where these occurred, Sertoli cells were immature and spermatogenesis was absent. Abnormal Sertoli cell-gonocyte interaction was evident at GD 19 in DBP-exposed rats coincident with appearance of multinucleated gonocytes, although these disappeared by postnatal day 10 during widespread loss of germ cells. CONCLUSIONS: Abnormal development of Sertoli cells, leading to abnormalities in other cell types, is our hypothesized explanation for the abnormal changes in DBP-exposed animals. As the testicular and other changes in DBP-exposed rats have all been reported in human TDS, DBP exposure in utero may provide a useful model for defining the cellular pathways in TDS.


Assuntos
Dibutilftalato , Modelos Animais de Doenças , Ratos Wistar , Doenças Testiculares/patologia , Testículo/anormalidades , Fatores Etários , Animais , Peso Corporal , Feminino , Humanos , Hiperplasia , Células Intersticiais do Testículo/patologia , Masculino , Tamanho do Órgão , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/patologia , Células de Sertoli/patologia , Espermatozoides/patologia , Doenças Testiculares/induzido quimicamente , Testículo/patologia , Testosterona/sangue
11.
Reprod Toxicol ; 15(3): 317-26, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11390175

RESUMO

The current study examines the actions of methoxychlor and its estrogenic metabolite, 2, 2-bis-(p-hydroxyphenyl)-1, 1, 1-trichloroethane (HPTE), on seminiferous cord formation and growth of the developing rat testis. The developing testis in the embryonic and early postnatal period is likely more sensitive to hormonally active agents than at later stages of development. Embryonic day 13 (E13) testis organ cultures were treated with either 0.2, 2, or 20 microM methoxychlor or 1, 3, 6, 15, 30, or 60 microM HPTE to examine effects on cord formation. No concentration of methoxychlor completely inhibited cord formation. However, cord formation was abnormal with the presence of a reduced number of cords and appearance of "swollen" cords at the 2 and 20 microM concentrations of methoxychlor. The swollen cords were due to an increase in the number of cells in a cord cross section and reduction of interstitial cell numbers between cords. Treatment of embryonic day 13 (E13) testes with HPTE caused abnormal cord formation at the 3 microM and 6 microM concentrations, and completely inhibited cord formation at the 15, 30, and 60 microM concentrations. In addition to the estrogenic metabolite HTPE, methoxychlor can also be metabolized into anti-androgenic compounds. Therefore, to determine the spectrum of potential actions of methoxychlor on testis development, different concentrations of estradiol, testosterone, and an anti-androgen (flutamide) were utilized to determine their effects on E13 testis organ culture morphology. Estradiol (1 microM) and flutamide (0.1microM) both inhibited seminiferous cord formation in E13 testis organ cultures. Therefore, methoxychlor may be acting through the androgen and/or estrogen receptors to elicit its actions on seminiferous cord formation. Reverse transcription polymerase chain reaction (PCR) (RT-PCR) confirmed the presence of estrogen receptor alpha (ERalpha) mRNA from embryonic day 14 (E14) through postnatal day 5 (P5) while estrogen receptor beta (ERbeta) mRNA did not appear until approximately E16 of testis development. Androgen receptor (AR) expression was present from E14 through P5 of testis development, but at apparently reduced levels at E14 and E16. Immunohistochemical analysis localized ERalpha to the cells of the seminiferous cords at E14 though P5 while ERbeta was present in cells of the interstitium at E16 and P0. Androgen receptor was localized to germ and interstitial cells. The effects of methoxychlor, HPTE, estradiol, and testosterone on cell growth of perinatal testes was determined with a thymidine incorporation assay in postnatal day zero (P0) testis cell cultures. Methoxychlor (0.002, 0.02, and 0.2 microM) and HPTE (2 and 20 microM) stimulated thymidine incorporation in P0 testis cell cultures in a similar manner to estradiol (0.01, 0.1, and 1 microM). In addition, testosterone (0.1 microM) also stimulated thymidine incorporation in P0 testis cultures. Observations suggest that methoxychlor and its metabolite HPTE can alter normal embryonic testis development and growth. The actions of methoxychlor and HPTE are likely mediated in part through the steroid receptors confirmed to be present in the developing testis.


Assuntos
Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Antagonistas de Estrogênios/toxicidade , Inseticidas/toxicidade , Metoxicloro/toxicidade , Fenóis/toxicidade , Túbulos Seminíferos/efeitos dos fármacos , Animais , Primers do DNA/química , Relação Dose-Resposta a Droga , Estradiol/toxicidade , Receptor beta de Estrogênio , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Flutamida/toxicidade , Masculino , Técnicas de Cultura de Órgãos , Gravidez , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genética , Receptores de Estrogênio/biossíntese , Receptores de Estrogênio/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/crescimento & desenvolvimento , Testosterona/toxicidade , Timidina/metabolismo
12.
Endocrinology ; 142(6): 2435-42, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356692

RESUMO

Aromatization of androgens is a key step in estrogen production, and it regulates the delicate balance between estrogens and androgens in the gonads and sex steroid target tissues. In the present study, we generated transgenic mice (AROM(+)) bearing the human ubiquitin C promoter/human P450 aromatase fusion gene. AROM(+) male mice are characterized by an imbalance in sex hormone metabolism, resulting in elevated serum E(2) concentrations, combined with significantly reduced testosterone and FSH levels, and elevated levels of PRL and corticosterone. AROM(+) males present a multitude of severe structural and functional alterations in the reproductive organs, such as cryptorchidism associated with Leydig cell hyperplasia, dysmorphic seminiferous tubules, and disrupted spermatogenesis. The males also have small or rudimentary accessory sex glands with abnormal morphology; a prominent prostatic utricle with squamous epithelial metaplasia, and edema in the ejaculatory ducts and vas deferens. In addition, the abdominal muscle wall is thin, and the adrenal glands are enlarged, with cortical hyperplasia. Some of the abnormalities, such as undescended testes and undeveloped prostate, resemble those observed in animals exposed perinatally to high levels of exogenous estrogen, indicating that the elevated aromatase activity results in excessive estrogen exposure during early phases of development. Some of the disorders in the reproductive organs, furthermore, can be explained by the fact that AROM(+) males are hypoandrogenic, and have elevated levels of serum PRL and corticosterone. Thus, the AROM(+) mouse model provides a novel tool to investigate the consequences of a prolonged increase in conversion of androgens to estrogens which results in complex hormonal disturbances altering the structure and function of various male reproductive organs.


Assuntos
Aromatase/genética , Expressão Gênica , Músculos Abdominais/anormalidades , Córtex Suprarrenal/patologia , Animais , Corticosterona/sangue , Criptorquidismo/enzimologia , Criptorquidismo/genética , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Genitália Masculina/anormalidades , Humanos , Hiperplasia , Células Intersticiais do Testículo/patologia , Masculino , Camundongos , Camundongos Transgênicos , Prolactina/sangue , Regiões Promotoras Genéticas , Próstata/anormalidades , Proteínas Recombinantes de Fusão , Túbulos Seminíferos/anormalidades , Espermatogênese/genética , Testosterona/sangue , Ubiquitinas/genética
13.
Fertil Steril ; 72(3): 467-71, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10519618

RESUMO

OBJECTIVE: To evaluate the use of percutaneous testicular sperm aspiration in the assessment of azoospermia and its association with seminiferous tubule microliths. DESIGN: Case report. SETTING: Tertiary care fertility center in a university hospital. PATIENT(S): Male undergoing infertility evaluation. INTERVENTION(S): Testicular biopsy and percutaneous testicular aspiration. MAIN OUTCOME MEASURE(S): Serum hormone analysis, sperm concentration in semen, spermatogenesis in samples from testicular biopsies and aspirations, and microlith composition. RESULT(S): A patient presented for infertility evaluation with a history of severe oligospermia that progressed to azoospermia. The serum testosterone concentration (357 ng/dL) and LH concentration (9.2 mIU/mL) were normal and the serum FSH concentration (18.3 mIU/mL) was elevated. Testicular biopsy results indicated spermatogenic hypoplasia with limited spermatozoa. Seminiferous tubules obtained by percutaneous testicular aspiration were structurally aberrant, with multiple diverticula. Microliths averaging 120 microm in diameter were observed within and blocking the seminiferous tubules. The microliths were composed of calcium phosphate (hydroxyapatite) in both the core and peripheral regions. Electron microscopy revealed a high degree of collagen-like material within the peripheral zone. CONCLUSION(S): The presence of seminiferous tubule microliths is associated with the development of azoospermia. In patients with a low incidence of seminiferous tubule microliths and aberrant seminiferous tubule architecture, percutaneous testicular aspiration may provide a diagnostic advantage over testicular biopsy.


Assuntos
Calcinose/diagnóstico , Oligospermia/etiologia , Túbulos Seminíferos/anormalidades , Doenças Testiculares/diagnóstico , Adulto , Biópsia , Calcinose/complicações , Calcinose/patologia , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Concentração de Íons de Hidrogênio , Hormônio Luteinizante/sangue , Masculino , Microscopia Eletrônica , Oligospermia/patologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatogênese , Doenças Testiculares/complicações , Doenças Testiculares/patologia , Testículo/patologia , Testosterona/sangue
14.
Eur J Endocrinol ; 140(1): 62-5, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10037254

RESUMO

A 4-year-old boy with an undescending left testis, penoscrotal hypospadia and bilateral microphthalmia was admitted to our hospital. Chromosome analysis revealed a karyotype of 46, XX del(x)(p2 2,31) and the sex-determining region of the Y chromosome (SRY) was negative. The right testis was located in the scrotum and a left cystic ovary-like gonad, a salpinx and a unicorn uterus were found in the left inguinal canal. Histologically the gonad was an ovotestis in which primordial follicles covered infantile seminiferous tubules. Microphthalmia is observed in some congenital syndromes caused by interstitial deletion of the X chromosome. This case suggested that the short arm of the X chromosome was involved in the differentiation of the gonad. Very closely located follicles and infantile seminiferous tubules indicated that induction of meiosis in the fetus was controlled by the local microenvironment in follicles and seminiferous tubules, and not by the systemic hormonal condition.


Assuntos
Transtornos do Desenvolvimento Sexual/genética , Hipospadia/genética , Microftalmia/genética , Criança , Transtornos do Desenvolvimento Sexual/cirurgia , Feminino , Deleção de Genes , Humanos , Hipospadia/cirurgia , Cariotipagem , Masculino , Microftalmia/cirurgia , Folículo Ovariano/anormalidades , Folículo Ovariano/cirurgia , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/cirurgia , Aberrações dos Cromossomos Sexuais/genética , Uretra/cirurgia
15.
An. Fac. Med. Univ. Fed. Pernamb ; 44(2): 122-5, 1999. ilus
Artigo em Português | LILACS | ID: lil-265627

RESUMO

Microlitíase testicular (MT) é uma condição rara, entretanto, vem sendo diagnosticada com maior frequência. Ela é caracterizada pela presença de múltiplas e pequenas calcificações intratesticulares. A etiologia é desconhecida, mas tem sido observada estar associada a uma variedade diferente de condições urológicas, entre elas varicocele e cisto do epidídimo como no presente relato. A associação de MT a neoplasias malignas e a subfertilidade/infertilidade, descrita na literatura, sugere a necessidade do acompanhamento regular (anual ou semestral) do testículo por ultra-som de alta resolução (7,5MHz). O achado incidental de MT associado à varicocele e cisto de epidídimo requer a inclusão desse paciente no protocolo de avaliação ultra-sonográfica periódica


Assuntos
Humanos , Masculino , Criança , Epididimo/fisiopatologia , Doenças Testiculares , Varicocele/cirurgia , Túbulos Seminíferos/anormalidades
16.
Chromosome Res ; 6(4): 285-94, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9688518

RESUMO

Three male mice with trisomy 19 induced by a Robertsonian translocation system were used for the study of meiotic prophase cells and germ cell differentiation. Present in these males were two Robertsonian chromosomes each with a chromosome 19 arm in common, two acrocentric chromosomes corresponding to the second arms of the two Rbs and one acrocentric chromosome 19. These five chromosomes showed a wide range of meiotic pairing configurations. One particular observation was the formation of a true double synaptonemal complex (SC) with three lateral axes and two central elements, which joined the three chromosomes 19 together. Integration of the acrocentric chromosome 19 in a complex pentavalent configuration was seen in 45% of the pachytene nuclei. The proportion of spermatocytes showing association between a quadrivalent and the acrocentric no. 19 was 26%. In 29% of the nuclei, the acrocentric no. 19 was free, integrated or associated with the XY complex, paired with the X chromosome or associated with a bivalent. Finally, in 57% of pachytene cells, the meiotic multivalents or the free univalent 19 were associated with the proximal part of the X chromosome or integrated in the sex chromatin. Therefore, the question arises with regard to the fate of these spermatocytes. The testicular histology shows an arrest of germ cell development at the spermatocyte stage. Several mechanisms seem to be the cause of germ cell depletion in a sequence of different, impaired developmental processes.


Assuntos
Meiose/fisiologia , Espermatócitos/fisiologia , Complexo Sinaptonêmico/fisiologia , Translocação Genética , Trissomia/fisiopatologia , Animais , Diploide , Heterozigoto , Cariotipagem , Masculino , Meiose/genética , Camundongos , Microscopia Eletrônica , Não Disjunção Genética , Prófase/genética , Prófase/fisiologia , Túbulos Seminíferos/anormalidades , Homologia de Sequência do Ácido Nucleico , Espermatogênese , Complexo Sinaptonêmico/genética , Testículo/anormalidades , Testículo/citologia , Trissomia/genética
17.
J Reprod Fertil ; 113(1): 91-3, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9713381

RESUMO

An adult male house muck shrew with an XXY sex chromosome constitution was found in a laboratory-bred colony. Maternal origin of the additional X chromosome was demonstrated. The external appearance of the animal was normal, but the testes were small and displayed a high density of interstitial cells. The seminiferous tubules were narrow and contained only Sertoli cells.


Assuntos
Aberrações dos Cromossomos Sexuais/patologia , Musaranhos/genética , Testículo/anormalidades , Cromossomo X , Animais , Masculino , Tamanho do Órgão , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/patologia , Testículo/patologia
18.
Development ; 124(22): 4595-603, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9409676

RESUMO

Spermatogenic cells synthesize a unique 70-kDa heat shock protein (HSP70-2) during prophase of meiosis I, and targeted disruption of the Hsp70-2 gene has shown that this protein is required for spermatogenic cell differentiation in adult mice. HSP70-2 is associated with synaptonemal complexes formed between paired homologous chromosomes during meiotic prophase. The present study focuses on the nearly synchronous first wave of spermatogenesis in 12- to 28-day old juvenile mice to determine more precisely when HSP70-2 is required and what meiotic processes are affected by its absence. Spermatogenesis in homozygous mutant mice (Hsp70-2[-/-]) proceeded normally until day 15 when increasing numbers of pachytene spermatocytes became apoptotic and differentiation of cells beyond the pachytene stage began to falter. Synaptonemal complexes assembled in Hsp70-2(-/-) mice and spermatocytes developed through the final pachytene substage. However, synaptonemal complexes failed to desynapse and normal diplotene spermatocytes were not observed. Metaphase spermatocytes were not seen in tissue sections from testes of Hsp70-2(-/-) mice, and expression of mRNAs and antigens characteristic of late pachytene spermatocytes (e.g., cyclin A1) and development of spermatids did not occur. Thus, HSP70-2 is required for synaptonemal complex desynapsis, and its absence severely impairs the transition of spermatogenic cells through the late meiotic stages and results in apoptosis beginning with the first wave of germ cell development in juvenile mice.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Espermatócitos/metabolismo , Animais , Apoptose , Sequência de Bases , Diferenciação Celular , Primers do DNA/genética , Proteínas de Choque Térmico HSP70/genética , Masculino , Meiose , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/metabolismo , Espermatócitos/ultraestrutura , Espermatogênese/genética , Espermatogênese/fisiologia , Complexo Sinaptonêmico/fisiologia , Testículo/anormalidades , Testículo/metabolismo
19.
Pediatr Med Chir ; 18(5 Suppl): 41-4, 1996.
Artigo em Italiano | MEDLINE | ID: mdl-9045223

RESUMO

A range of epididymal and vasal anomalies (EVA), varying from ductal patency aberrations to abnormal attachments of the epidydimis to the testis or even complete absence, exists in boys with cryptorchidism, but there are few studies of normal controls for comparison. In the present study anatomy of testicular-epididymal relationships were recorded in 517 cryptorchid patients (423 unilateral and 94 bilateral) and in 192 boys who underwent inguinal exploration for inguinal hernia or hydrocele. The postmortem anatomic relationship of the testis and epididymis in 50 adults was also examined. The operative findings were divided into two groups: simple variants of normal and forms of complete anatomic disconnection of the spermatic ducts (EVA). We were unable to find EVA in the control groups. In contrast EVA was present in the 20% of cryptorchid patients. The incidence was 16.5% in unilateral cryptorchidism and 26% in bilateral cases, in 17% of whom the EVA was bilateral. According to the literature and our previous study azoospermia is present in about 18-20% of adults operated upon in childhood for bilateral cryptorchidism. Our present study may suggest that azoospermia in adults operated on for bilateral cryptorchidism could be partially related to some forms of bilateral occlusion or interruption of the spermatic ducts.


Assuntos
Criptorquidismo/complicações , Epididimo/anormalidades , Oligospermia/etiologia , Adulto , Criança , Epididimo/anatomia & histologia , Humanos , Masculino , Túbulos Seminíferos/anormalidades
20.
Urol Int ; 52(2): 118-20, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8178376

RESUMO

We report a case of pericentric inversion of chromosome 9 associated with Sertoli-cell-only tubule. The literature is reviewed, and the hormonal profile and testicular histology are discussed.


Assuntos
Inversão Cromossômica , Cromossomos Humanos Par 9 , Túbulos Seminíferos/anormalidades , Células de Sertoli/patologia , Adulto , Aberrações Cromossômicas , Transtornos Cromossômicos , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Masculino , Túbulos Seminíferos/patologia
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