RESUMO
Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene SRY is present in many cases, the etiology is unknown in most SRY-negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms' tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families (P = 4.4 × 10-6), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations (P < 1.8 × 10-4). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and Wt1Arg495Gly/Arg495Gly XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor ß-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.
Assuntos
Transtornos Testiculares 46, XX do Desenvolvimento Sexual/metabolismo , Testículo/metabolismo , Proteínas WT1/metabolismo , Transtornos Testiculares 46, XX do Desenvolvimento Sexual/genética , Transtornos Testiculares 46, XX do Desenvolvimento Sexual/patologia , Animais , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Camundongos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Testículo/crescimento & desenvolvimento , Testículo/patologia , Proteínas WT1/química , Proteínas WT1/genética , Dedos de Zinco , beta Catenina/genética , beta Catenina/metabolismoRESUMO
BACKGROUND: IGF1R gene mutations have been associated with varying degrees of intrauterine and postnatal growth retardation, and microcephaly. OBJECTIVE: To identify and characterize IGF1R gene variations in a cohort of 28 Argentinean children suspected of having IGF-1 insensitivity, who were selected on the basis of the association of pre/postnatal growth failure and microcephaly. METHODS: The coding sequence and flanking intronic regions of IGF1R gene were amplified and directly sequenced. Functional characterization was performed by two in vitro assays: 1) [Methyl-(3) H] thymidine incorporation into DNA in fibroblast cell primary cultures from patients and controls treated with IGF-1 for 16-24 h. 2) PI3K/Akt pathway was evaluated with phospho-Akt (Ser473) STAR ELISA Kit (Millipore) in fibroblast cultures from patients and controls stimulated with IGF-1 for 10 min. Prepubertal clinical and GH-IGF-1 axis evaluation was followed up. RESULTS: We identified three novel heterozygous missense mutations in three unrelated patients, de novo p.Arg1256Ser, de novo p.Asn359Tyr and p.Tyr865Cys. In control cells, proliferation assay showed that IGF-1 significantly induced DNA synthesis at 20 h and Akt phosphorylation assay that it significantly stimulated phosphorylation after 10 min (P < 0·05 by anova and Bonferroni Tests). However, no significant increase was observed in any of the three patient fibroblasts in both functional studies. GH therapy growth response in two patients was inconsistent. CONCLUSION: These variations led to failure of the IGF1R function causing pre- and postnatal growth retardation and microcephaly. Microcephaly should be considered in the evaluation of SGA patients, because it seems to favour the frequency of detection of IGF1R mutations.
Assuntos
Transtornos do Crescimento/genética , Microcefalia/genética , Mutação , Receptores de Somatomedina/genética , Adulto , Argentina , Biópsia , Criança , Pré-Escolar , Estudos de Coortes , DNA/genética , Análise Mutacional de DNA , Feminino , Retardo do Crescimento Fetal/genética , Fibroblastos/metabolismo , Variação Genética , Heterozigoto , Hormônio do Crescimento Humano/metabolismo , Humanos , Lactente , Fator de Crescimento Insulin-Like I/metabolismo , Íntrons , Masculino , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1RESUMO
StAR facilitates cholesterol entry into the mitochondria as part of the transduceosome complex. Recessive mutations in the gen STAR cause classic and nonclassic congenital lipoid adrenal hyperplasia. The aim of the study was to analyze the molecular consequences of a novel heterozygous STAR mutation in a 46,XY patient with ambiguous genitalia and adrenal insufficiency. We found a de novo heterozygous IVS-2A>G STAR mutation and the reported heterozygous p.G146A SF1 polymorphism with normal CYP11A1, FDXR, FDX1, VDAC1 and TSPO genes. RT-PCR and sequencing from patient's testicular RNA showed a -exon2 transcript and the wild-type (WT) transcript. Both 37 kDa precursor and 30 kDa mature protein were detected in COS-7 cell transfected with mutant and WT plasmids. Immunofluorescence showed almost no co-localization of mitochondria and mutant protein (delta22-59StAR). Delta22-59StAR activity was 65±13% of WT. Cotransfection with WT and delta22-59StAR plasmids reduced WT activity by 62.0% ± 13.9. Novel splice-junction heterozygous STAR mutation (IVS-2A>G) resulted in the in-frame loss of amino acids 22 to 59 in the N-terminal mitochondrial targeting signal. A misfolded p.G22_L59delStAR might interfere with WT StAR activity by blocking the transduceosome complex, causing an autosomal dominant form of StAR deficiency, explaining the clinical phenotype.
Assuntos
Hiperplasia Suprarrenal Congênita/genética , Transtorno 46,XY do Desenvolvimento Sexual/genética , Mutação/genética , Fosfoproteínas/genética , Insuficiência Adrenal/genética , Animais , Células COS , Chlorocebus aethiops , Humanos , Recém-Nascido , Masculino , Linhagem , Fenótipo , Polimorfismo Genético , Reação em Cadeia da Polimerase em Tempo RealRESUMO
BACKGROUND: Persistent müllerian duct syndrome (PMDS) is characterized by the persistence of müllerian duct derivatives in otherwise normally virilized 46,XY males. Biallelic mutations of the anti-müllerian hormone (AMH) and AMH receptor type 2 (AMHR2) genes lead to PMDS type 1 and 2, respectively. AIM: The aims of the study were to report the clinical, hormonal, and genetic findings in a patient with PMDS and discuss surgical strategies to achieve successful orchidopexy. RESULTS: A 4-year-old boy was evaluated after the incidental finding of müllerian derivates during laparoscopy for nonpalpable gonads. Karyotype was 46,XY and laboratory tests revealed normal serum gonadotropin and androgen levels but undetectable serum AMH levels. PMDS was suspected. Molecular analysis revealed a novel variant c.902_929del in exon 5 and a previously reported mutation (c.367C>T) in exon 1 of the AMH gene. Successful orchidopexy was performed in two sequential surgeries in which the müllerian duct structure was preserved and divided to protect the vascular supply to the gonads. Histological evaluation of the testicular biopsy showed mild signs of dysgenesis. Doppler ultrasound showed blood flow in both testes positioned in the scrotum 1.5 years after surgery. CONCLUSION: PMDS is a rare entity that requires a high index of suspicion (from surgeons) when evaluating a patient with bilateral cryptorchidism. Surgical treatment is challenging and long-term follow-up is essential. Histological evaluation of the testis deserves further investigation.
Assuntos
Transtorno 46,XY do Desenvolvimento Sexual , Laparoscopia , Masculino , Humanos , Pré-Escolar , Hormônio Antimülleriano/genética , Transtorno 46,XY do Desenvolvimento Sexual/genética , Transtorno 46,XY do Desenvolvimento Sexual/cirurgia , Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Mutação/genéticaRESUMO
Niemann-Pick type C (NP-C) is a rare, autosomal recessive disorder. At least 95% of all the cases with this disease are due to mutations in the NPC1 gene. The clinical signs and symptoms of NP-C are classified into visceral, neurological and psychiatric. Our aim is to report the clinical findings, molecular results and filipin staining of 4 patients. The age of onset, expressed as median and range, was 0.2 (0.08-4.0) years and the age of diagnosis was 4.0 (2.5-8.9) years. Neurological and/or visceral manifestations were presented in our patients. Foamy cells in bone marrow biopsy were found in two patients. Through a molecular analysis of NPC1 gene, one non-reported (novel) and 4 previously described mutations were found. The filipin staining showed a positive pattern in all the patients. The diagnostic confirmation of these pediatric patients means a contribution to the casuistry of this disease in Argentina.
Niemann-Pick tipo C (NP-C) es una enfermedad poco frecuente, con un patrón de herencia autosómico recesivo. Al menos el 95% de los casos se producen por mutaciones en el gen NPC1. Los signos y síntomas clínicos de NP-C se clasifican en viscerales, neurológicos y psiquiátricos. En este trabajo presentamos los hallazgos clínicos, los resultados moleculares y la tinción con filipina de 4 pacientes con NP-C. La edad de presentación de los primeros síntomas, expresada como mediana y rango, fue de 0.2 años (0.08-4.0) años y la edad del diagnóstico fue 4.0 (2.5-8.9) años. Los pacientes presentaron manifestaciones neurológicas y / o viscerales. Se encontraron células espumosas en la biopsia de médula ósea en 2 pacientes. El análisis molecular del gen NPC1 encontró 1 variante nueva y 4 previamente publicadas. La tinción de filipina mostró un patrón positivo en todos los pacientes. La confirmación diagnóstica de este grupo de pacientes pediátricos significa un aporte a la casuística de esta enfermedad en Argentina.
Assuntos
Doença de Niemann-Pick Tipo C , Argentina , Criança , Filipina , Humanos , Lactente , Mutação , Doença de Niemann-Pick Tipo C/diagnóstico , Doença de Niemann-Pick Tipo C/genética , Doença de Niemann-Pick Tipo C/psicologiaRESUMO
Recent reports indicate an increase in Leydig cell tumor (LCT) incidence. Radical orchiectomy is the standard therapy in children and adults, although it entails physical and psychosocial side effects. Testis-sparing surgery can be a consideration for benign LCT of 2.5 cm or less in size. Malignant LCTs respond poorly to conventional chemotherapy, so new treatment modalities are needed. In this study, we observed increased histidine decarboxylase expression and pro-angiogenic potential in LCT surgically resected from pediatric patients (fetal to pubertal) vs control samples from patients without endocrine or metabolic disorders which were collected at necropsy. We, therefore, evaluated for the first time the antitumor efficacy of two histidine decarboxylase inhibitors (α-methyl-dl-histidine dihydrochloride (α-MHD) and epigallocatechin gallate (EGCG)), alone and combined with carboplatin, in two preclinical models of LCT. MA-10 and R2C Leydig tumor cells, representing two different LCT subtypes, were used to generate syngeneic and xenograft mouse LCT models, respectively. In the syngeneic model, monotherapy with α-MHD effectively reduced tumor growth and angiogenesis. In the xenografts, which showed co-expression of histidine decarboxylase and CYP19, the combination of EGCG plus carboplatin was the most effective therapy, leading to LCT growth arrest and undetectable levels of plasmatic estradiol. Testicular and body weights remained unaltered. On the basis of this study, histidine decarboxylase may emerge as a novel pharmacological target for LCT treatment.
Assuntos
Tumor de Células de Leydig , Neoplasias Testiculares , Animais , Aromatase , Carboplatina , Estradiol , Histidina , Histidina Descarboxilase/genética , Humanos , Tumor de Células de Leydig/metabolismo , Tumor de Células de Leydig/patologia , Tumor de Células de Leydig/cirurgia , Masculino , Camundongos , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patologia , Neoplasias Testiculares/cirurgiaRESUMO
Background: Differences/disorders of sex development (DSD) are congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical. Objective: The aim of this study is to report the histological characteristics and immunoexpression patterns of gonadal parenchyma in patients with 46,XX testicular and ovotesticular DSD, with a focus on the detection of germ cell malignancies. Design: Inclusion criteria were SRY-negative 46,XX testicular and ovotesticular DSD with available samples from gonadal biopsy or gonadectomy for the review of histological findings. Gonadal histology was assessed on hematoxylin and eosin-stained sections and immunohistochemical analysis. Histopathological criteria from the last World Health Organization classification of urogenital tumors were used to identify undifferentiated gonadal tissue, gonadoblastoma, and dysgerminoma. Results: Median age at first histological evaluation of gonadal samples was 1.46 years (range: 0.16-16 years). Totally 15 patients were classified as ovotesticular and only 1 as testicular DSD. Most individuals had bilateral ovotestes (12/15). No histological alterations were found in the ovarian parenchyma, while signs of dysgenesis were seen in all cases of testicular parenchyma. In 4/15 ovotesticular DSD, a prepubertal biopsy failed to identify ovarian parenchyma. We detected early prepubertal preinvasive and invasive malignancies in this cohort (five patients had undifferentiated gonadal tissue, five gonadoblastoma, and one dysgerminoma). Conclusion: 46,XX disorders of gonadal development are historically considered at a low risk for germ cell cancer, and the need for assessment of gonadal histology has been questioned. The finding of early germ cell malignancies in our cohort brings awareness and needs further research.
Assuntos
Transtornos do Desenvolvimento Sexual , Disgerminoma , Gonadoblastoma , Neoplasias Embrionárias de Células Germinativas , Neoplasias Ovarianas , Transtornos Ovotesticulares do Desenvolvimento Sexual , Transtornos do Desenvolvimento Sexual/diagnóstico , Disgerminoma/genética , Feminino , Gonadoblastoma/genética , Gonadoblastoma/patologia , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Ovarianas/patologia , Transtornos Ovotesticulares do Desenvolvimento Sexual/diagnóstico , Transtornos Ovotesticulares do Desenvolvimento Sexual/genéticaRESUMO
Several reports in humans as well as transgenic mouse models have shown that estrogens play an important role in male reproduction and fertility. Estrogen receptor alpha (ERα) and beta (ERß) are expressed in different male tissues including the brain. The estradiol-binding protein GPER1 also mediates estrogen action in target tissues. In human testes a minimal ERα expression during prepuberty along with a marked pubertal up-regulation in germ cells has been reported. ERß expression was detected mostly in spermatogonia, primary spermatocytes, and immature spermatids. In Sertoli cells ERß expression increases with age. The aromatase enzyme (cP450arom), which converts androgens to estrogens, is widely expressed in human tissues (including gonads and hypothalamus), even during fetal life, suggesting that estrogens are also involved in human fetal physiology. Moreover, cP450arom is expressed in the early postnatal testicular Leydig cells and spermatogonia. Even though the aromatase complex is required for estrogen synthesis, its biological relevance is also related to the regulation of the balance between androgens and estrogens in different tissues. Knockout mouse models of aromatase (ArKO) and estrogen receptors (ERKOα, ERKOß, and ERKOαß) provide an important tool to study the effects of estrogens on the male reproductive physiology including the gonadal axis. High basal serum FSH levels were reported in adult aromatase-deficient men, suggesting that estrogens are involved in the negative regulatory gonadotropin feedback. However, normal serum gonadotropin levels were observed in an aromatase-deficient boy, suggesting a maturational pattern role of estrogen in the regulation of gonadotropin secretion. Nevertheless, the role of estrogens in primate testis development and function is controversial and poorly understood. This review addresses the role of estrogens in gonadotropin secretion and testicular physiology in male humans especially during childhood and puberty.
Assuntos
Estrogênios/farmacologia , Regulação da Expressão Gênica no Desenvolvimento , Gonadotropinas/metabolismo , Puberdade , Testículo/fisiologia , Animais , Humanos , Masculino , Testículo/efeitos dos fármacosRESUMO
Objective: The aim of this study was the molecular characterization of the AR gene as the cause of 46,XY disorder in our population. Methods: We studied 41, non related, 46,XY disorder of sexual differentiation index cases, having characteristics consistent with androgen insensivity syndrome (AIS). Genomic DNA was isolated from peripheral blood leukocytes of all patients and 25 family members from 17 non-related families. Results: The AR gene analysis revealed an abnormal sequence in 58.5% of the index patients. All of the complete AIS (CAIS) cases were genetically confirmed, while in the partial form (PAIS) a mutation in AR was detected in only 13 (43.3%). Molecular studies revealed other affected or carrier relatives in 87% of the index cases. The AR mutations were found spread along the whole coding sequence, with a higher prevalence in the ligand binding domain. Nine out of 23 (39%) AR mutations were novel. In 17% of patients with detected AR mutations, somatic mosaicism was detected in leucocyte DNA. In our cohort, long-term follow up gender dysphoria, raised as male or female, was not found. Finally, in suspected PAIS, the identification of AR mutation occurred significantly less than in CAIS patients. Conclusion: Improved knowledge of the components of the AR complex and signaling network might contribute to long term outcome and genetic counseling in AIS patients.
Assuntos
Síndrome de Resistência a Andrógenos/genética , Síndrome de Resistência a Andrógenos/fisiopatologia , Receptores Androgênicos/genética , Análise de Sequência de DNA , Adolescente , Síndrome de Resistência a Andrógenos/patologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mosaicismo , Linhagem , Fenótipo , Centros de Atenção TerciáriaRESUMO
Uterine receptivity and embryo implantation are two main processes that need a finely regulated balance between pro-inflammatory and tolerogenic mediators to allow a successful pregnancy. The neuroimmune peptide vasoactive intestinal peptide (VIP) is a key regulator, and it is involved in the induction of regulatory T cells (Tregs), which are crucial in both processes. Here, we analyzed the ability of endogenous and exogenous VIP to sustain a tolerogenic microenvironment during the peri-implantation period, particularly focusing on Treg recruitment. Wild-type (WT) and VIP-deficient mice [heterozygous (HT, +/-), knockout (KO, -/-)], and FOXP3-knock-in-GFP mice either pregnant or in estrus were used. During the day of estrus, we found significant histological differences between the uterus of WT mice vs. VIP-deficient mice, with the latter exhibiting undetectable levels of FOXP3 expression, decreased expression of interleukin (IL)-10, and vascular endothelial growth factor (VEGF)c, and increased gene expression of the Th17 proinflammatory transcription factor RORγt. To study the implantation window, we mated WT and VIP (+/-) females with WT males and observed altered FOXP3, VEGFc, IL-10, and transforming growth factor (TGF)ß gene expression at the implantation sites at day 5.5 (d5.5), demonstrating a more inflammatory environment in VIP (+/-) vs. VIP (+/+) females. A similar molecular profile was observed at implantation sites of WT × WT mice treated with VIP antagonist at d3.5. We then examined the ability GFP-sorted CD4+ cells from FOXP3-GFP females to migrate toward conditioned media (CM) obtained from d5.5 implantation sites cultured in the absence/presence of VIP or VIP antagonist. VIP treatment increased CD4+FOXP3+ and decreased CD4+ total cell migration towards implantation sites, and VIP antagonist prevented these effects. Finally, we performed adoptive cell transfer of Tregs (sorted from FOXP3-GFP females) in VIP-deficient-mice, and we observed that FOXP3-GFP cells were mainly recruited into the uterus/implantation sites compared to all other tested tissues. In addition, after Treg transfer, we found an increase in IL-10 expression and VEGFc in HT females and allowed embryo implantation in KO females. In conclusion, VIP contributes to a local tolerogenic response necessary for successful pregnancy, preventing the development of a hostile uterine microenvironment for implantation by the selective recruitment of Tregs during the peri-implantation period.
Assuntos
Implantação do Embrião/imunologia , Placenta/imunologia , Linfócitos T Reguladores/imunologia , Útero/imunologia , Peptídeo Intestinal Vasoativo/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Microambiente Celular , Feminino , Fatores de Transcrição Forkhead/imunologia , Interleucina-10/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Gravidez , Fator A de Crescimento do Endotélio Vascular/imunologiaRESUMO
Leydig-cell tumours (LCTs) are rare endocrine tumours of the testicular interstitium, with recent increased incidence. Symptoms include precocious puberty in children; and erectile dysfunction, infertility and/or gynaecomastia, in adults. So far, scientific evidence points to aromatase (CYP19) overexpression and excessive oestrogen and insulin-like growth factor (IGF) -1 production as responsible for Leydig-cell tumourigenesis. LCTs are usually benign; however, malignant LCTs respond poorly to chemo/radiotherapy, highlighting the need to identify novel targets for treatment. Herein, we investigated the potential role of the histamine receptor H4 (HRH4) as a therapeutic target for LCTs using R2C rat Leydig tumour cells, a well-documented in vitro model for Leydigioma. Also, we studied for the first time the expression of CYP19, IGF-1R, oestrogen receptor (ER) α, ERß, androgen receptor (AR) and HRH4 in human prepubertal LCTs versus normal prepubertal testes (NPTs). HRH4 agonist treatment inhibited steroidogenesis and proliferation in R2C cells and also negatively affected their pro-angiogenic capacity in vitro and in vivo, as assessed by evaluating the proliferative activity of human umbilical vein endothelial cells and by means of the quail chorioallantoic membrane assay, respectively. Moreover, E2 and IGF-1 inhibited HRH4 mRNA and protein levels. In human prepubertal LCTs, CYP19, IGF-1R, ERα and ERß were overexpressed compared with NPTs. In contrast, HRH4 staining was weak in LCTs, but moderate/strong and confined to the interstitium in NPTs. Importantly, HRH4 was absent or barely detectable in seminiferous tubules or germ cells. Overall, our results point to HRH4 as a novel therapeutic target in LCTs.
Assuntos
Antineoplásicos/farmacologia , Guanidinas/farmacologia , Agonistas dos Receptores Histamínicos/farmacologia , Imidazóis/farmacologia , Tumor de Células de Leydig/tratamento farmacológico , Receptores Histamínicos H4/agonistas , Neoplasias Testiculares/tratamento farmacológico , Tioureia/análogos & derivados , Fatores Etários , Inibidores da Angiogênese/farmacologia , Animais , Aromatase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Coturnix/embriologia , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lactente , Tumor de Células de Leydig/metabolismo , Tumor de Células de Leydig/patologia , Masculino , Terapia de Alvo Molecular , Neovascularização Patológica , Ratos , Receptor IGF Tipo 1 , Receptores Androgênicos/metabolismo , Receptores Histamínicos H4/metabolismo , Receptores de Somatomedina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Inibidores da Síntese de Esteroides/farmacologia , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patologia , Tioureia/farmacologiaRESUMO
CONTEXT: The mechanisms of postnatal adrenal zonation remain unclear. OBJECTIVE: To provide a clue for a possible role of estrogens in adrenarche, we studied the expression of estrogen receptor (ER)alpha, ERbeta, G protein-coupled receptor (GPR)30, and cP450aromatase (cP450arom) in human adrenal tissue. DESIGN: Human adrenal tissue was collected from three postnatal age groups (Grs): Gr 1, younger than 3 months (n = 12), fetal zone involution; Gr 2, 3 months to 6 yr (n = 17), pre-adrenarche; and Gr 3, older than 6-20 yr (n = 12), post-adrenarche period. RESULTS: ERbeta mRNA in Grs 1 and 3 was higher than in Gr 2 (P < 0.05). By immunohistochemistry and laser capture microdissection followed by RT-PCR, ERbeta was expressed in zona reticularis and fetal zone, GPR30 in zona glomerulosa (ZG) and adrenal medulla, while ERalpha mRNA and protein were undetectable. cP450arom mRNA in Gr 3 was higher than in Grs 1 and 2 (P < 0.05), and localized to ZG and adrenal medulla by laser capture microdissection. cP450arom Immunoreactivity was observed in adrenal medulla in the three Grs and in subcapsular ZG of Gr 3. Double-immunofluorescence studies revealed that cP450arom and chromogranin A only colocalize in adrenal medulla of subjects younger than 18 months. In these samples, exon 1.b-derived transcript was 3.5-fold higher, while exon 1.a-, 1.c-, and 1.d-derived transcripts were 3.3-, 1.9-, and 1.7-fold lower, respectively, than in subjects older than 6 yr. CONCLUSIONS: Our results suggest that estrogens produced locally in adrenal medulla would play a role in zona reticularis functional differentiation through ERbeta. The cP450arom and GPR30 expression in subcapsular ZG, colocalizing with a high-cell proliferation index, previously reported, suggests a local GPR30-dependent estrogen action in proliferation and migration of progenitor adrenal cells.
Assuntos
Córtex Suprarrenal/crescimento & desenvolvimento , Medula Suprarrenal/crescimento & desenvolvimento , Adrenarca/fisiologia , Aromatase/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Adolescente , Córtex Suprarrenal/citologia , Córtex Suprarrenal/enzimologia , Medula Suprarrenal/citologia , Medula Suprarrenal/enzimologia , Adulto , Aromatase/genética , Criança , Pré-Escolar , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Éxons , Imunofluorescência , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Humanos , Lactente , Puberdade/fisiologia , RNA Mensageiro/metabolismoRESUMO
P450 aromatase (P450Aro), involved in androgen to estrogen conversion, is encoded by the CYP19 gene. P450Aro c655G>A mutation described in heterozygous form in a girl and in homozygous form in an adult male with P450Aro deficiency results in an aberrant splicing due to disruption of a donor splice site. A truncated inactive protein would be expected if intron5 is retained. Surprisingly, the girl described with this mutation showed spontaneous breast development and pubertal estradiol (E2) levels suggesting residual P450Aro activity (AA). Formerly, we postulate the in frame E5 skipping as a consequence of this mutation generating a protein with some degree of activity. When P450Aro mRNA expression was analysed from patient's lymphocytes, an aberrant spliced mRNA lacking E5 (-E5mRNA) was detected, suggesting an association between E5 skipping and the presence of the mutation. Splicing assays in Y1 cells confirmed this association. -Ex5 cDNA expression in Y1 cells resulted in an inactive protein that could not explain patient's phenotype. Exon 5 might be predicted as a poorly defined exon suggesting a susceptibility to splicing mutations and physiological alternative splicing (AS) events. Therefore, -Ex5mRNA was assessed as a natural occurring alternative transcript in normal human steroidogenic tissues. As P450Aro -E5mRNA expression was detected in human term placenta, prepubertal testis and prepubertal adrenal, we might speculate that AS of P450Aro coding region would occur in humans and would be involved in the complex AA regulation. Furthermore, tissue specific regulation of AS might suggest low expression of +E5mRNA from the c655G>A allele explaining residual AA evidenced in the affected girl.
Assuntos
Processamento Alternativo/genética , Aromatase/genética , Estrogênios/biossíntese , Éxons/genética , Mutação/genética , Sequência de Aminoácidos , Animais , Aromatase/deficiência , Estradiol/sangue , Feminino , Humanos , Masculino , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Desenvolvimento Sexual/genéticaRESUMO
Abstract Niemann-Pick type C (NP-C) is a rare, autosomal recessive disorder. At least 95% of all the cases with this disease are due to mutations in the NPC1 gene. The clinical signs and symptoms of NP-C are classified into visceral, neurological and psychiatric. Our aim is to report the clinical findings, molecular results and filipin staining of 4 patients. The age of onset, expressed as median and range, was 0.2 (0.08-4.0) years and the age of diagnosis was 4.0 (2.5-8.9) years. Neurological and/or visceral manifestations were presented in our patients. Foamy cells in bone marrow biopsy were found in two patients. Through a molecular analysis of NPC1 gene, one non-reported (novel) and 4 previously described mutations were found. The filipin staining showed a positive pattern in all the patients. The diagnostic confirmation of these pediatric patients means a contribution to the casuistry of this disease in Argentina.
Resumen Niemann-Pick tipo C (NP-C) es una enfermedad poco frecuente, con un patrón de herencia au tosómico recesivo. Al menos el 95% de los casos se producen por mutaciones en el gen NPC1. Los signos y síntomas clínicos de NP-C se clasifican en viscerales, neurológicos y psiquiátricos. En este trabajo presentamos los hallazgos clínicos, los resultados moleculares y la tinción con filipina de 4 pacientes con NP-C. La edad de presentación de los primeros síntomas, expresada como mediana y rango, fue de 0.2 años (0.08-4.0) años y la edad del diagnóstico fue 4.0 (2.5-8.9) años. Los pacientes presentaron manifestaciones neurológicas y / o vis cerales. Se encontraron células espumosas en la biopsia de médula ósea en 2 pacientes. El análisis molecular del gen NPC1 encontró 1 variante nueva y 4 previamente publicadas. La tinción de filipina mostró un patrón positivo en todos los pacientes. La confirmación diagnóstica de este grupo de pacientes pediátricos significa un aporte a la casuística de esta enfermedad en Argentina.
RESUMO
We hypothesized that DNA methylation is involved in human adrenal functional zonation. mRNAs expression and methylation pattern of RARB, NR4A1 and HSD3B2 genes in human adrenal tissues (HAT) and in pediatric virilizing adrenocortical tumors (VAT) were analyzed. For analysis of the results samples were divided into 3 age groups according to FeZ involution, pre and post-adrenarche ages. In all HAT, similar RARB mRNA was found including microdissected zona reticularis (ZR) and zona fasciculata, but HSD3B2 and NR4A1 mRNAs were lower in ZR (p < 0.05). NR4A1 and RARB promoters remained unmethylated in HAT and VAT. No adrenal zone-specific differences in NR4A1 methylation were observed. In summary, RARB was not associated with ZR-specific downregulation of HSD3B2 in postnatal human adrenocotical zonation. DNA methylation would not be involved in NR4A1 adrenocortical cell-type specific downregulation. Lack of CpG islands in HSD3B2 suggested that HSD3B2 ZR-specific downregulation would not be directly mediated by DNA methylation.
Assuntos
Córtex Suprarrenal/citologia , Androgênios/metabolismo , Metilação de DNA/genética , Regulação para Baixo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Progesterona Redutase/genética , Receptores do Ácido Retinoico/genética , Adolescente , Neoplasias do Córtex Suprarrenal/genética , Criança , Pré-Escolar , Ilhas de CpG/genética , Regulação da Expressão Gênica , Humanos , Lactente , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Progesterona Redutase/metabolismo , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico/metabolismo , Adulto JovemRESUMO
Androgen insensitivity syndrome (AIS) is a hereditary condition in patients with a 46,XY karyotype in which loss-of-function mutations of the androgen receptor (AR) gene are responsible for defects in virilization. The aim of this study was to investigate the consequences of the lack of AR activity on germ cell survival and the degree of testicular development reached by these patients by analyzing gonadal tissue from patients with AIS prior to Sertoli cell maturation at puberty. Twenty-three gonads from 13 patients with AIS were assessed and compared to 18 testes from 17 subjects without endocrine disorders. The study of the gonadal structure using conventional microscopy and the ultrastructural characteristics of remnant germ cells using electron microscopy, combined with the immunohistochemical analysis of specific germ cell markers (MAGE-A4 for premeiotic germ cells and of OCT3/4 for gonocytes), enabled us to carry out a thorough investigation of germ cell life in an androgen-insensitive microenvironment throughout prepuberty until young adulthood. Here, we show that germ cell degeneration starts very early, with a marked decrease in number after only 2 years of life, and we demonstrate the permanence of gonocytes in AIS testis samples until puberty, describing 2 different populations. Additionally, our results provide further evidence for the importance of AR signaling in peritubular myoid cells during prepuberty to maintain Sertoli and spermatogonial cell health and survival.
Assuntos
Síndrome de Resistência a Andrógenos/patologia , Puberdade/metabolismo , Puberdade/fisiologia , Síndrome de Resistência a Andrógenos/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Criança , Pré-Escolar , Células Germinativas/metabolismo , Humanos , Imuno-Histoquímica , Lactente , Masculino , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Proteínas de Transporte de Cátions Orgânicos/genética , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Espermatogônias/metabolismo , Espermatogônias/patologia , Testículo/metabolismo , Testículo/patologiaRESUMO
Programmed cell death and proliferation are evolutionary conserved processes that play a major role during normal development and homeostasis. In the testis, during the fetal and newborn periods, they might determine final adult size and fertility potential. In the present study, we have measured the relative number of testicular cells in apoptosis and in active proliferation in the seminiferous cords and in the interstitium, at different age periods of prepubertal testicular development in humans. Testes from 44 prepubertal subjects without endocrine and metabolic abnormalities were collected at necropsy. They were divided in three age groups (Gr): Gr 1, newborn (1- to 21-d-old neonates), n = 18, mean (+/-SD) age 0.3 +/- 0.23 months; Gr 2, post natal activation (1- to 6-month-old infants), n = 13, mean age 3.93 +/- 1.90 months; and Gr 3, early childhood period (1- to <6-yr-old boys), n = 13, mean age 31.5 +/- 18.9 months. Apoptosis was detected in 5- microm tissue sections using a modified terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay and cell proliferation was assessed by Ki-67 immunohistochemistry. Evaluation of apoptosis was confirmed by estimation of active caspase-3. Mean (+/-SD) testicular weight was 0.38 +/- 0.20, 0.54 +/- 0.35, and 0.51 +/- 0.11 g in Gr 1, Gr 2, and Gr 3, respectively. In Gr 1, there was a significant positive correlation between age and testis weight (P = 0.02). Mean (+/-SD) germ cell apoptotic index, AI, (% of apoptotic cells out of total cell number) was 15.0 +/- 6.60, 27.0 +/- 8.80 and 33.4 +/- 11.4 in Gr 1, Gr 2, and Gr 3, respectively. In Sertoli cells, it was 6.60 +/- 4.07, 22.0 +/- 14.0 and 27.5 +/- 19.8, respectively. In interstitial cells, it was 10.2 +/- 6.38, 18.0 +/- 6.70 and 25.7 +/- 15.5, respectively. In the three types of cells, AI in Gr 1 was significantly lower than in Gr 2 or Gr 3 (P < 0.05). Mean (+/-SD) germ cell proliferation index, PI, was 18.6 +/- 13.0, 10.0 +/- 6.50 and 10.9 +/- 6.24% in Gr 1, Gr 2, and Gr 3, respectively. In Sertoli cells and in interstitial cells PI was similar in the three age groups. The PI/AI ratio was used to compare relative differences among age groups. The PI/AI ratio of germ cells, Sertoli cells and interstitial cells in Gr 1 was significantly higher than in Gr 2 or Gr 3 (P < 0.05). It is concluded that, in normal subjects, there is a vigorous growth of the testis during the newborn period with subsequent stabilization during the first years of prepuberty. This cell growth seems to be mainly mediated by decreased apoptosis. The factors that modulate apoptosis of testicular cells are not known, but it is remarkable that this change takes place before the testosterone peak of the post natal gonadal activation of the first trimester of life. These changes taking place during the newborn period might be important to define testicular function in adults.
Assuntos
Apoptose , Divisão Celular , Espermatozoides/citologia , Testículo/citologia , Testículo/crescimento & desenvolvimento , Envelhecimento , Caspase 3 , Caspases/análise , Pré-Escolar , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Lactente , Recém-Nascido , Antígeno Ki-67/análise , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/enzimologia , Masculino , Tamanho do Órgão , Puberdade , Células de Sertoli/citologia , Células de Sertoli/enzimologia , Espermatozoides/enzimologiaRESUMO
The histamine H4 receptor (HRH4), discovered only 13 years ago, is considered a promising drug target for allergy, inflammation, autoimmune disorders and cancer, as reflected by a steadily growing number of scientific publications and patent applications. Although the presence of HRH4 has been evidenced in the testis, its specific localization or its role has not been established. Herein, we sought to identify the possible involvement of HRH4 in the regulation of Leydig cell function. We first evaluated its expression in MA-10 Leydig tumor cells and then assessed the effects of two HRH4 agonists on steroidogenesis and proliferation. We found that HRH4 is functionally expressed in MA-10 cells, and that its activation leads to the inhibition of LH/human chorionic gonadotropin-induced cAMP production and StAR protein expression. Furthermore, we observed decreased cell proliferation after a 24-h HRH4 agonist treatment. We then detected for the sites of HRH4 expression in the normal rat testis, and detected HRH4 immunostaining in the Leydig cells of rats aged 7-240 days, while 21-day-old rats also presented HRH4 expression in male gametes. Finally, we evaluated the effect of HRH4 activation on the proliferation of normal progenitor and immature rat Leydig cell culture, and both proved to be susceptible to the anti-proliferative effect of HRH4 agonists. Given the importance of histamine (2-(1H-imidazol-4-yl)ethanamine) in human (patho)physiology, continued efforts are directed at elucidating the emerging properties of HRH4 and its ligands. This study reveals new sites of HRH4 expression, and should be considered in the design of selective HRH4 agonists for therapeutic purposes.
Assuntos
Proliferação de Células , Células Intersticiais do Testículo/metabolismo , Progesterona/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Histamínicos/metabolismo , Animais , Western Blotting , Bucladesina/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Gonadotropina Coriônica/farmacologia , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Guanidinas/farmacologia , Agonistas dos Receptores Histamínicos/farmacologia , Imuno-Histoquímica , Indóis/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Microscopia Confocal , Oximas/farmacologia , Fosfoproteínas/metabolismo , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/agonistas , Receptores Histamínicos H4 , Testículo/metabolismo , Tioureia/análogos & derivados , Tioureia/farmacologiaRESUMO
CONTEXT: Steroid acute regulatory (StAR) protein is a mitochondria-targeted protein that is part of the transduceosome complex crucial for transport of cholesterol to mitochondria. Recessive mutations cause classic and nonclassic congenital lipoid adrenal hyperplasia. OBJECTIVE: The aim of this study was to report the clinical, hormonal, genetic, and functional data of a novel heterozygous mutation in the StAR gene found in a 46,XY patient with ambiguous genitalia and neonatal severe steroidogenic deficiency. PATIENT: Undetectable serum steroids with high ACTH and plasma renin activity but normal acute GnRH response were found in infancy. After gonadectomy (at 3 yr of age), serum LH and testosterone were undetectable, whereas FSH was normal but increased slowly afterward. Estrogen replacement therapy, started at 10.2 yr of age, suppressed gonadotropins (for 2 yr). However, after 1 month off estrogens, the patient showed castrated levels. At 11.9 yr old, after fludrocortisone withdrawal because of hypertension, plasma renin activity and aldosterone remained normal, suggesting mineralocorticoid recovery by a StAR-independent mechanism. RESULTS: We found a de novo heterozygous IVS-2A>G StAR mutation and the reported heterozygous p.G146A SF1 polymorphism with normal CYP11A1, FDXR, FDX1, VDAC1, and TSPO genes. The mutant StAR transcript lacked exon 2, resulting in the in-frame loss of amino acids 22 to 59 in the N-terminal mitochondrial targeting signal. In vitro, the mutant protein exhibited reduced StAR activity in a dominant-negative manner and almost no mitochondria localization. CONCLUSIONS: A misfolded p.G22_L59del StAR might interfere with wild-type StAR activity by blocking the transduceosome complex, causing an autosomal dominant form of StAR deficiency, explaining the clinical phenotype. We speculated that estrogen might have modulated mineralocorticoid function and pubertal maturation in a human natural model lacking endogenous steroid production.
Assuntos
Hiperplasia Suprarrenal Congênita/genética , Transtorno 46,XY do Desenvolvimento Sexual/genética , Mitocôndrias/metabolismo , Mutação de Sentido Incorreto , Fosfoproteínas/genética , Sinais Direcionadores de Proteínas/genética , Animais , Células COS , Criança , Chlorocebus aethiops , Transtornos do Desenvolvimento Sexual/genética , Feminino , Genes Dominantes/genética , Humanos , Recém-Nascido , Masculino , Mutação de Sentido Incorreto/fisiologia , Linhagem , Polimorfismo de Nucleotídeo Único/fisiologia , Estrutura Terciária de Proteína/genética , Transporte Proteico/genéticaRESUMO
In humans, steroidogenic factor 1 (NR5A1/SF-1) mutations have been reported to cause gonadal dysgenesis, with or without adrenal failure, in both 46,XY and 46,XX individuals. We have previously reported extreme within-family variability in affected 46,XY patients. Even though low ovarian reserve with preserved fertility has been reported in females harboring NR5A1 gene mutations, fertility has only been observed in one reported case in affected 46,XY individuals. A kindred with multiple affected members presenting gonadal dysgenesis was studied. Four 46,XY individuals presented severe hypospadias at birth, one of them associated with micropenis and cryptorchidism. The other 3 developed spontaneous male puberty, and 1 has fathered 5 children. Four 46,XX patients presented premature ovarian failure (one of them was not available for the study) or high follicle-stimulating hormone levels. Mutational analysis of the NR5A1 gene revealed a novel heterozygous mutation, c.938GâA, predicted to cause a p.Arg313Hys amino acid change. A highly conserved amino acid of the ligand-binding domain of the mature protein is affected, predicting abnormal protein function. We confirm that preserved fertility can be observed in patients with a 46,XY disorder of sex development due to heterozygous mutations in the NR5A1 gene.