RESUMO
Prokineticin receptor 2 (PROKR2) encodes for a G-protein-coupled receptor that can bind PROK1 and PROK2. Mice lacking Prokr2 have been shown to present abnormal olfactory bulb formation as well as defects in GnRH neuron migration. Patients carrying mutations in PROKR2 typically present hypogonadotropic hypogonadism, anosmia/hyposmia or Kallmann Syndrome. More recently variants in PROKR2 have been linked to several other endocrine disorders. In particular, several patients with pituitary disorders have been reported, ranging from mild phenotypes, such as isolated growth hormone deficiency, to more severe ones, such as septo-optic dysplasia. Here we summarize the changing landscape of PROKR2-related disease, the variants reported to date, and discuss their origin, classification and functional assessment.
Assuntos
Síndrome de Kallmann , Neuropeptídeos , Camundongos , Animais , Neuropeptídeos/metabolismo , Síndrome de Kallmann/genética , Genótipo , Receptores Acoplados a Proteínas G/genética , Fenótipo , Receptores de Peptídeos/genéticaRESUMO
OBJECTIVE: Kallmann's syndrome (KS) is characterized by hypogonadotropic hypogonadism and olfactory disorders. The complementary exams for evaluating of patients with hypogonadotrophic hypogonadism are important for the diagnosis and management of these patients. PATIENTS: We performed a well-established olfactory Sniffin' Stick test (SST) on 17 adult patients with KS and brain magnetic resonance imaging (MRI) to evaluate olfactory structures and further analysis by Freesurfer, a software for segmentation and volumetric evaluation of brain structures. We compared the Freesurfer results with 34 healthy patients matched for age and sex and performed correlations between the data studied. RESULTS: More than half of the patients with KS reported preserved smell but had olfactory disorders in the SST. In the MRI, 16 patients showed changes in the olfactory groove, the olfactory bulb-tract complex was altered in all of them and 52% had symmetrical structural changes. Interestingly, the pituitary gland was normal in only 29%. Regarding correlations, symmetrical changes in the olfactory structures were related to anosmia in 100%, while asymmetric changes induced anosmia in only 50% (p = .0294). In Freesurfer's assessment, patients with KS, compared to controls, had lower brainstem volume. In those with aplastic anterior olfactory sulcus, the brainstem volume was lower than in hypoplasia (p = .0333). CONCLUSIONS: Olfactory assessment and MRI proved to be important auxiliary tools for the diagnosis and management of patients with KS. New studies are needed to confirm the decrease in brainstem volume found by the Freesurfer software in patients with KS. Further studies are needed to confirm the decrease in brainstem volume found by the Freesurfer software in patients with KS.
Assuntos
Hipogonadismo , Síndrome de Kallmann , Síndrome de Klinefelter , Transtornos do Olfato , Adulto , Humanos , Síndrome de Kallmann/diagnóstico , Olfato , Anosmia/patologia , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/patologia , Hipogonadismo/diagnóstico , Encéfalo/patologiaRESUMO
Abstract Epiphysiolysis is a relatively common disease in the adolescent population (9-16 years); however, it is rare in the adult population. It is characterized by non-traumatic proximal femur slipping. When it occurs in this population it is associated with some disease that slows sexual development and physis closure, such as endocrine diseases or brain tumors. The aim of the present study is to report a case of epiphysiolysis in a 22-year-old patient with hypogonadotropic hypogonadism. There are only 63 cases reported in the world literature on epiphysiolysis in the adult population.
Resumo A epifisiólise é uma doença relativamente comum na população adolescente (de 9-16 anos), entretanto rara na população adulta. Se caracteriza pelo escorregamento metáfiso-epifisário do fêmur proximal não-traumático. Quando ocorre nessa população, está associada a alguma doença que retarda o desenvolvimento sexual e fechamento fisário, como doenças endocrinológicas ou tumores cerebrais. O objetivo do presente estudo é relatar um caso de epifisiólise numa paciente com 22 anos de idade e hipogonadismo hipogonadotrófico. Existem apenas 63 casos relatados na literatura mundial sobre epifisiólise na população adulta.
Assuntos
Humanos , Feminino , Adulto , Síndrome de Kallmann , Epifise Deslocada , Cabeça do FêmurRESUMO
CONTEXT: Congenital hypogonadotropic hypogonadism (CHH) is a rare condition caused by GnRH deficiency. Several genes have been associated with the pathogenesis of CHH, but most cases still remain without a molecular diagnosis. The advent of next-generation sequencing (NGS) has allowed the simultaneous genotyping of several regions, faster, making possible the extension of the genetic knowledge of CHH. OBJECTIVE: Genetic characterization of a large cohort of Brazilian CHH patients. DESIGN AND PATIENTS: A cohort of 130 unrelated patients (91 males, 39 females) with CHH (75 normosmic CHH, 55 Kallmann syndrome) was studied using a panel containing 36 CHH-associated genes. RESULTS: Potential pathogenic or probably pathogenic variants were identified in 43 (33%) CHH patients. The genes ANOS1, FGFR1 and GNRHR were the most frequently affected. A novel homozygous splice site mutation was identified in the GNRH1 gene and a deletion of the entire coding sequence was identified in SOX10. Deleterious variants in the IGSF10 gene were identified in two patients with reversible normosmic CHH. Notably, 6.9% of the patients had rare variants in more than one gene. Rare variants were also identified in SPRY4, IL17RD, FGF17, IGSF1 and FLRT3 genes. CONCLUSIONS: This is a large study of the molecular genetics of CHH providing new genetic findings for this complex and heterogeneous genetic condition. NGS has been shown to be a fast, reliable and effective tool in the molecular diagnosis of congenital CHH and being able to targeting clinical genetic testing in the future.
Assuntos
Hipogonadismo/congênito , Hipogonadismo/genética , Mutação , Adulto , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Brasil/epidemiologia , Proteínas de Transporte/genética , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Testes Genéticos , Glicoproteínas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/epidemiologia , Imunoglobulinas/genética , Síndrome de Kallmann/diagnóstico , Síndrome de Kallmann/epidemiologia , Síndrome de Kallmann/genética , Fator de Transcrição MSX1/genética , Masculino , Proteínas de Membrana/genética , Fatores de Transcrição Otx/genética , Linhagem , Receptores de Grelina/genética , Ribonucleoproteínas/genética , Ubiquitina-Proteína Ligases , Adulto JovemAssuntos
Síndrome de Kallmann/complicações , Síndrome de Kallmann/patologia , Transtornos dos Movimentos/etiologia , Tratos Piramidais/patologia , Adulto , Imagem de Tensor de Difusão , Proteínas da Matriz Extracelular/genética , Humanos , Imageamento Tridimensional , Síndrome de Kallmann/diagnóstico por imagem , Síndrome de Kallmann/genética , Masculino , Córtex Motor/diagnóstico por imagem , Transtornos dos Movimentos/diagnóstico por imagem , Mutação/genética , Proteínas do Tecido Nervoso/genética , Desempenho Psicomotor/fisiologia , Tratos Piramidais/diagnóstico por imagemRESUMO
Introducción: El hipogonadismo hipogonadotrófico asociado a alteraciones del olfato (HHAAO), esuna variante de hipogonadismo hipogonadotrófico, que se asocian a un defecto en la hipófisis o en elhipotálamo, obedeciendo a una falta de hormonas que en condiciones normales estimulan a los ovarioso los testículos.Casos clínicos: Este protocolo se originó a partir de pacientes que consultaron por alteraciones del olfato, desde octubre de 2013 hasta octubre de 2014, de30 pacientes entre 6 a 16 años, se detectaron 3 mujeres menores de 15 años de edad; que presentaron anosmia constatada por olfatometría y ausencia debulbos olfatorios en resonancia magnética nuclear. Una paciente presentó hipoacusia...
Introduction: The hypogonadotropic hypogonadism associated with disturbances of smell (HHAAO),is a variant of hypogonadotropic hypogonadism, which are associated to a defect in thepituitary or hypothalamus, obeying a lack of hormonesthat normally stimulate the ovaries or thetesticles. Clinical case: This originated from patients who consulted for disorders of smell, from October 2013to October 2014, 30 patients aged 6-16 years were detected, 3 women under 15 years of age; they hadanosmia proven by olfactometry and absence of olfactory bulbs in Nuclear Magnetic Resonance. Onepatient had hearing lost...
Introdução: O hipogonadismo hipogonadotrófico associada a distúrbios do olfato (HHAAO), é uma variante de hipogonadismo hipogonadotrófico, que estão associados a um defeito na hipófise ou hipotálamo,obedecendo a uma falta de hormônios que normalmente estimulam os ovários ou os testículos.Caso clínico: Este provenientes de pacientes que consultaram para distúrbios do olfato, a partir de outubro 2013 a outubro de 2014, 30 pacientes comida de entre 6-16 anos foram detectados, três mulheres com menos de 15 anos de idade; eles tinha manosmia comprovada por olfatometria e ausência de bulbos olfatórios em Ressonância Magnética Nuclear.Um paciente apresentou perda auditiva...
Assuntos
Humanos , Adolescente , Feminino , Criança , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/etiologia , Protocolos Clínicos , Deficiências do Desenvolvimento/diagnóstico , Hipogonadismo/complicações , Hipogonadismo/congênito , Hipogonadismo/diagnóstico , Puberdade Tardia/diagnóstico , Síndrome de Kallmann/diagnósticoRESUMO
OBJECTIVE: To investigate the role of KAL1 abnormalities in Brazilian patients with Kallmann syndrome. DESIGN: In vitro experiments. SETTING: Academic medical center. PATIENT(S): One hundred fifteen Brazilian patients (98 men) with Kallmann syndrome. INTERVENTION(S): Peripheral blood leukocytes were used to obtain DNA. MAIN OUTCOME MEASURE(S): Direct sequencing and multiplex ligation-dependent probe amplification were used to identify KAL1 abnormalities. RESULT(S): We identified four KAL1 mutations (p.Met1?, p.Ala33Glyfs, p.Arg257*, and p.Trp462*) and two multiple exon deletions (exons 1-2 and 3-14) in six new male patients. Overall, 17 KAL1 defects (14.8%) were identified in the entire cohort of patients with Kallmann syndrome, including previously studied cases. KAL1-mutated patients presented with a more severe reproductive and nonreproductive phenotype (synkinesia, renal malformations, cryptorchidism, and anatomic olfactory abnormalities) in comparison with patients without KAL1 mutations. Intragenic deletions were one of the most often encountered defects (29.4%). These deletions can be missed by polymerase chain reaction (PCR) due to Yq11.2 KAL1 pseudogene (KALP) spurious amplification. CONCLUSION(S): These results indicate that intragenic multiexon deletions are one of the most frequent KAL1 abnormalities, which can be more accurately detected by multiplex ligation-dependent probe amplification. In addition, KAL1 sequencing results should be interpreted with caution, and stringency conditions of the PCR reaction should be adjusted to avoid pseudogene amplification.
Assuntos
Análise Mutacional de DNA/métodos , Proteínas da Matriz Extracelular/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Síndrome de Kallmann/genética , Reação em Cadeia da Polimerase Multiplex , Proteínas do Tecido Nervoso/genética , Adulto , Automação , Sequência de Bases , Análise Mutacional de DNA/instrumentação , Feminino , Frequência do Gene , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Humanos , Síndrome de Kallmann/diagnóstico , Síndrome de Kallmann/epidemiologia , Masculino , Mutação/genética , Mutação/fisiologia , Prevalência , Pseudogenes/genéticaRESUMO
Kallmann syndrome is characterized by hypogonadotropic hypogonadism and anosmia/hyposmia. The hypogonadotropic hypogonadism is due to deficiency of gonadotropin-releasing hormone, caused by a defect in the migration of neurons synthesizing gonadotropin-releasing hormone, and anosmia/hyposmia is related to the absence or hypoplasia of the olfactory bulb and tracts. Some patients may have other associated abnormalities such as renal agenesis, cleft palate, dental agenesis, synkinesis, shortening of metacarpal, sensory neural hearing loss and seizures. The aim of this paper is to present an updated review of the clinical and molecular basis, highlighting the relevance of knowledge of phenotypic variants in Kallmann syndrome.
Assuntos
Síndrome de Kallmann/genética , Humanos , Síndrome de Kallmann/diagnóstico , FenótipoAssuntos
Humanos , Masculino , Feminino , Recém-Nascido , Aberrações Cromossômicas , Deleção Cromossômica , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda , Diagnóstico , Hibridização in Situ Fluorescente , Síndrome de Angelman/diagnóstico , Síndrome de Kallmann/diagnóstico , Síndrome de Prader-Willi/diagnóstico , Síndrome de Smith-Magenis/diagnóstico , Síndrome de Williams/diagnósticoRESUMO
O hipogonadismo hipogonadotrófico isolado (HHI) congênito caracteriza-se pela falta completa ou parcial de desenvolvimento puberal em decorrência de defeitos na migração, síntese, secreção ou ação do hormônio liberador de gonadotrofinas (GnRH). Baixas concentrações de esteroides sexuais e valores reduzidos ou inapropriadamente normais de gonadotrofinas hipofisárias (LH e FSH) definem, do ponto de vista laboratorial, essa condição clínica. A secreção dos demais hormônios hipofisários encontra-se normal, bem como a ressonância magnética de região hipotalâmica-hipofisária, demonstrando a ausência de uma causa anatômica. Alterações olfatórias, como anosmia ou hiposmia, podem estar associadas ao HHI, caracterizando a síndrome de Kallmann. Uma lista crescente de genes está envolvida na etiologia do HHI, sugerindo a heterogeneidade e a complexidade da base genética dessa condição. Distúrbios na rota de migração dos neurônios secretores de GnRH e dos neurônios olfatórios formam a base clínico-patológica da síndrome de Kallmann. Mutações nos genes KAL1, FGFR1/FGF8, PROK2/PROKR2, NELF, CHD7, HS6ST1 e WDR11 foram associadas a defeitos de migração neuronal, causando a síndrome de Kallmann. É notável que defeitos nos genes FGFR1, FGF8, PROKR2, CHD7 e WDR11 foram também associados ao HHI sem alterações olfatórias (HHI normósmico), porém em menor frequência. Adicionalmente, defeitos nos KISS1R, TAC3/TACR3 e GNRH1/GNRHR foram descritos exclusivamente em pacientes com HHI normósmico. Neste trabalho, revisaremos as características clínicas, hormonais e genéticas do HHI.
Congenital isolated hypogonadotropic hypogonadism (IHH) is characterized by partial or complete lack of pubertal development due to defects in migration, synthesis, secretion or action of gonadotropin-releasing hormone (GnRH). Laboratory diagnosis is based on the presence of low levels of sex steroids, associated with low or inappropriately normal levels of pituitary gonadotropins (LH and FSH). Secretion of other pituitary hormones is normal, as well magnetic resonance imaging of the hypothalamohypophyseal tract, which shows absence of an anatomical defects. When IHH is associated with olfactory abnormalities (anosmia or hyposmia), it characterizes Kallmann syndrome. A growing list of genes is involved in the etiology of IHH, suggesting the heterogeneity and complexity of the genetic bases of this condition. Defects in olfactory and GnRH neuron migration are the etiopathogenic basis of Kallmann syndrome. Mutations in KAL1, FGFR1/FGF8, PROK2/PROKR2, NELF, CHD7, HS6ST1 and WDR11 are associated with defects in neuronal migration, leading to Kallmann syndrome. Notably, defects in FGFR1, FGF8, PROKR2, CHD7 and WDR11 are also associated with IHH, without olfactory abnormalities (normosmic IHH), although in a lower frequency. Mutations in KISS1R, TAC3/TACR3 and GNRH1/GNRHR are described exclusively in patients with normosmic IHH. In this paper, we reviewed the clinical, hormonal and genetic aspects of IHH.
Assuntos
Humanos , Hormônio Liberador de Gonadotropina/genética , Hipogonadismo/genética , Síndrome de Kallmann/genética , Mutação/genética , Movimento Celular/genética , Hormônio Liberador de Gonadotropina , Hipogonadismo/congênito , NeurôniosRESUMO
CONTEXT: Necdin activates GNRH gene expression and is fundamental for the development, migration, and axonal extension of murine GNRH neurons. In humans, necdin plays a potential role in the hypogonadotropic hypogonadism phenotype in patients with Prader-Willi syndrome. AIM: To investigate necdin gene (NDN) variants in patients with isolated hypogonadotropic hypogonadism (IHH). PATIENTS AND METHODS: We studied 160 Brazilian patients with IHH, which includes 92 with Kallmann syndrome and 68 with normosmic IHH. Genomic DNA was extracted and the single NDN exon was amplified and sequenced. To measure GNRH transcriptional activity, luciferase reporter plasmids containing GNRH regulatory regions were transiently transfected into GT1-7 cells in the presence and absence of overexpressed wild-type or mutant necdin. RESULTS: A heterozygous variant of necdin, p.V318A, was identified in a 23-year-old male with Kallmann syndrome. The p.V318A was also present in affected aunt and his father and was absent in 100 Brazilian control subjects. Previous FGFR1 gene analysis revealed a missense mutation (p.P366L) in this family. Functional studies revealed a minor difference in the activation of GNRH transcription by mutant protein compared with wild type in that a significant impairment of the necdin protein activity threshold was observed. CONCLUSION: A rare variant of necdin (p.V318A) was described in a family with Kallmann syndrome associated with a FGFR1 mutation. Familial segregation and in vitro analysis suggested that this non-synonymous variant did not have a direct causative role in the hypogonadism phenotype. NDN mutations are not a frequent cause of congenital IHH.
Assuntos
Hipogonadismo/genética , Síndrome de Prader-Willi/genética , Animais , Sequência de Bases , Brasil , Análise Mutacional de DNA , Feminino , Humanos , Hipogonadismo/congênito , Síndrome de Kallmann/genética , Masculino , Camundongos , Proteínas do Tecido Nervoso , Proteínas Nucleares , Linhagem , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genéticaRESUMO
OBJECTIVES: To measure olfactory bulbs and sulci using dedicated magnetic resonance imaging (MRI) sequences and specific measurement tools in Kallmann syndrome (KS) patients with a well-established genotype and phenotype, as well as correlate MRI findings with a clinical smell test. METHODS: MRI was performed in 21 patients with KS and 16 healthy volunteers; olfactory dysfunction was assessed using the Smell Identification Test (UPSIT), a qualitative suprathreshold olfaction test. Coronal turbo spin echo T2-weighted and volumetric T1-weighted gradient echo sequences were acquired in a 1.5T system. ImageJ software was used to obtain olfactory bulb volumes and olfactory sulcus depths and lengths. Data were analyzed with SPSS 15.0 and the Kappa index was used to evaluate the agreement between the UPSIT and MRI. RESULTS: The UPSIT showed 14 patients with anosmia and 6 with moderate hyposmia. Eighteen patients (85%) presented altered rhinencephalon structures in the MRI. Sixteen patients (76%) presented olfactory bulb aplasia (14/16 bilaterally), and these patients presented a total of 16 aplastic sulci. There was moderate agreement between the MRI quantitative evaluation and the UPSIT (overall Kappa = 0.55), but when considering the presence of aplastic bulbs and anosmia, we found almost perfect agreement (Kappa = 0.87). Three patients had normal rhinencephalon structures, including one with a KAL1 gene mutation. CONCLUSION: Olfactory bulb and sulcus aplasia were the most common findings in KS patients. We objectively demonstrated agreement between MRI findings and the smell test, especially the presence of bulb aplasia and anosmia. Therefore, our findings help ascertain MRI accuracy in the diagnosis of KS, differentiating patients with hypogonadotropic hypogonadism with an apparently normal or difficult to evaluate sense of smell.
Assuntos
Técnicas de Diagnóstico Neurológico , Síndrome de Kallmann/diagnóstico por imagem , Imageamento por Ressonância Magnética , Bulbo Olfatório/diagnóstico por imagem , Olfato/fisiologia , Adolescente , Adulto , Criança , Humanos , Síndrome de Kallmann/complicações , Síndrome de Kallmann/epidemiologia , Síndrome de Kallmann/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/etiologia , Bulbo Olfatório/fisiopatologia , Radiografia , Adulto JovemRESUMO
Pulsatile secretion of Gonadotropin-Releasing Hormone (GnRH) by the hipothalamus and its action on the pituitary gland is a complex process involving many pre and post natal events. For example, migration of GnRH neurons from the olfactory placode, GnRH release and signalling, normal anterior pituitary development and function are all needed to allow GnRH to stimulate pulsaltile pituitary secretion of follicle-stimulating hormone (FSH) and liteinizing hormone (LH). Hypogonadotropic hypogonadism can be the result of absent or inadequate GnRH secretion or action. Abnormalities in gonadotropin hormone release and function can arise from mutations in a variety of genes implicated in hypogonadotropic hypogonadism is continually growing. A given genotype at a single locus cannot reliably predict the phenotypic manifestations in any given member of affected families. Thus, the identification and characterization of these mutations are providing important information about the reproductive axis in humans and may result in improved treatment and counselling for patients with infertility.
Assuntos
Humanos , Hormônio Liberador de Gonadotropina/biossíntese , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina , Fertilidade , Hormônio Foliculoestimulante , Gonadotropinas/biossíntese , Gonadotropinas/genética , Gonadotropinas , Hipogonadismo/genética , Hormônio Luteinizante , Mutação , Hipófise , Reprodução , Síndrome de Kallmann/genéticaRESUMO
Congenital isolated hypogonadotropic hypogonadism (IHH) is characterized by partial or complete lack of pubertal development due to defects in migration, synthesis, secretion or action of gonadotropin-releasing hormone (GnRH). Laboratory diagnosis is based on the presence of low levels of sex steroids, associated with low or inappropriately normal levels of pituitary gonadotropins (LH and FSH). Secretion of other pituitary hormones is normal, as well magnetic resonance imaging of the hypothalamohypophyseal tract, which shows absence of an anatomical defects. When IHH is associated with olfactory abnormalities (anosmia or hyposmia), it characterizes Kallmann syndrome. A growing list of genes is involved in the etiology of IHH, suggesting the heterogeneity and complexity of the genetic bases of this condition. Defects in olfactory and GnRH neuron migration are the etiopathogenic basis of Kallmann syndrome. Mutations in KAL1, FGFR1/FGF8, PROK2/PROKR2, NELF, CHD7, HS6ST1 and WDR11 are associated with defects in neuronal migration, leading to Kallmann syndrome. Notably, defects in FGFR1, FGF8, PROKR2, CHD7 and WDR11 are also associated with IHH, without olfactory abnormalities (normosmic IHH), although in a lower frequency. Mutations in KISS1R, TAC3/TACR3 and GNRH1/GNRHR are described exclusively in patients with normosmic IHH. In this paper, we reviewed the clinical, hormonal and genetic aspects of IHH.
Assuntos
Hormônio Liberador de Gonadotropina/genética , Hipogonadismo/genética , Síndrome de Kallmann/genética , Mutação/genética , Movimento Celular/genética , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Hipogonadismo/congênito , Neurônios/metabolismoRESUMO
Kallmann syndrome (KS), characterized by the association of hypogonadotropic hypogonadism and anosmia, may present many other phenotypic abnormalities, including neurologic features as involuntary movements, called mirror movements (MM). MM etiology probably involves a complex mechanism comprising corticospinal tract abnormal development associated with deficient contralateral motor cortex inhibitory system. In this study, in order to address previous hypotheses concerning MM etiology, we identified and quantified white matter (WM) alterations in 21 KS patients, comparing subjects with and without MM and 16 control subjects, using magnetization transfer ratio (MTR) and T2 relaxometry (R2). Magnetization transfer and T2 double-echo images were acquired in a 1.5 T system. MTR and R2 were calculated pixel by pixel to initially create individual maps, and then, group average maps, co-registered with MNI305 stereotaxic coordinate system. After analysis of selected regions of interest, we demonstrated areas with higher T2 relaxation time and lower MTR values in KS patients, with and without MM, differently involving corticospinal tract projection, frontal lobes and corpus callosum. Higher MTR was observed only in pyramidal decussation when compared in both groups of patients with controls. In conclusion, we demonstrated that patients with KS have altered WM areas, presenting in a different manner in patients with and without MM. These data suggest axonal loss or disorganization involving abnormal pyramidal tracts and other associative/connective areas, relating to the presence or absence of MM. We also found a different pattern of alteration in pyramidal decussation, which can represent the primary area of neuronal disarrangement.
Assuntos
Encéfalo/patologia , Síndrome de Kallmann/patologia , Imageamento por Ressonância Magnética , Transtornos dos Movimentos/patologia , Fibras Nervosas Mielinizadas/fisiologia , Adolescente , Adulto , Criança , Humanos , Processamento de Imagem Assistida por Computador , Síndrome de Kallmann/complicações , Masculino , Pessoa de Meia-Idade , Movimento , Transtornos dos Movimentos/complicaçõesRESUMO
O sistema da procineticina desempenha um papel importante na migração dos neurônios secretores de GnRH e na neurogênese do bulbo olfatório. Camundongos com ablação dos genes que codificam a procineticina 2 (PROK2) e seu receptor (PROKR2) apresentaram fenótipos semelhantes ao da síndrome de Kallmann descrita em humanos. Mutações inativadoras nos genes PROK2 e PROKR2 foram identificadas em pacientes com hipogonadismo hipogonadotrófico isolado. Com base nestes achados, investigamos a presença de alterações estruturais nos genes PROK2 e PROKR2 em 107 pacientes brasileiros (63 com síndrome de Kallmann e 47 com hipogonadismo hipogonadotrófico isolado normósmico). Cem indivíduos brasileiros que relataram desenvolvimento puberal normal foram utilizados como grupo controle. As regiões codificadoras dos genes PROK2 e PROKR2 foram amplificadas utilizando-se oligonucleotídeos intrônicos específicos, seguida de purificação enzimática e sequenciamento automático. Duas mutações no gene PROK2 foram identificadas: a mutação p.G100fsX121 em homozigose presente em dois irmãos com síndrome de Kallmann; e a mutação p.I55fsX56 em heterozigose identiificada em um paciente com HHIn. Quatro mutações foram identificadas no gene PROKR2 (p.R80C, p.Y140X, p.L173R e p.R268C) em cinco pacientes com síndrome de Kallmann e um paciente com HHIn. Essas mutações não foram encontradas no grupo controle. As mutações do tipo missense, p.R80C, p.L173R e p.R268C foram identificadas em heterozigose. Mutações nos genes FGFR1, GnRHR, KiSS-1 e GPR54 foram excluídas nesses pacientes. O paciente portador da mutação p.R268C do PROKR2 apresentou deleção dos exons 1 e 2 do gene KAL1. Adicionalmente, as mutações p.R80C e p.R268C foram identificadas em heterozigose em parentes de primeiro grau assintomáticos dos casos índices. A nova mutação p.Y140X do PROKR2, única alteração em homozigose, foi identificada em um paciente com micropênis, criptorquidia bilateral, anosmia e palato ogival. Os pais deste...
Physiological activation of the prokineticin pathway has a critical role in olfactory bulb morphogenesis and GnRH secretion. Knock-out mice for genes that encode prokineticin 2 (PROK2) and the prokineticin receptor 2 (PROKR2) exhibited a phenotype similar to the Kallmann syndrome (KS). Inactivating mutations in PROK2 and PROKR2 have been identified in patients with isolated hypogonadotropic hypogonadism. Based on these findings, we investigated the presence of inactivating mutations of the genes PROK2 and PROKR2 in Brazilian patients with isolated hypogonadotropic hypogonadism associated or not with olfactory abnormalities and performed in vitro studies of the new identified mutations. We studied 107 patients with HH (63 with Kallmann syndrome and 44 with normosmic HH) and 100 control individuals. The coding regions of PROK2 and PROKR2 were amplified by polymerase chain reaction followed by enzymatic purification and direct automatic sequencing. In PROK2, two known frameshift mutations were identified. Two brothers with Kallmann syndrome harbored the homozygous p.G100fsX121 mutation, whereas one male with normosmic HH harbored the heterozygous p.I55fsX56 mutation. In PROKR2, four distinct mutations (p.R80C, p.Y140X, p.L173R and p.R268C) were identified in five patients with Kallmann syndrome and in one patient with normosmic HH. These mutations were not found in the control group. The p.R80C and p.R268C missense mutations were identified in heterozygous state in the HH patients and in their asymptomatic first-degree relatives. The p.L173R was also identified in heterozygous state. In addition, no mutations of FGFR1, GnRHR, KiSS-1 or GPR54 were identified in these patients. The patient with the PROKR2 mutation p.R268C also has a deletion of the exon 1 and 2 in the gene KAL1. Notably, the new nonsense mutation (p.Y140X) was identified in homozygous state in an anosmic boy with micropenis, bilateral cryptorchidism and high-arched palate. His asymptomatic...
Assuntos
Bulbo Olfatório/citologia , Genes , Hormônio Liberador de Gonadotropina , Hipogonadismo , Síndrome de Kallmann , MutaçãoRESUMO
Por considerar infrecuentes los síndromes de aicardi, de Kallmann y de sturge-Weber, la leucodistrofia metacromática y la malformación de la vena de Galeno con síndrome de hipotensión endocraneana, en este artículo se describe un caso de cada una de estas enfermedades con los hallazgos imaginológicos y un resumen teórico de cada uno de ellos.
Assuntos
Humanos , Síndrome de Kallmann , Leucodistrofia Metacromática , Síndrome de Sturge-Weber , Malformações da Veia de GalenoRESUMO
BACKGROUND AND PURPOSE: There are 2 main hypotheses concerning the cause of mirror movements (MM) in Kallmann syndrome (KS): abnormal development of the primary motor system, involving the ipsilateral corticospinal tract; and lack of contralateral motor cortex inhibitory mechanisms, mainly through the corpus callosum. The purpose of our study was to determine white and gray matter volume changes in a KS population by using optimized voxel-based morphometry (VBM) and to investigate the relationship between the abnormalities and the presence of MM, addressing the 2 mentioned hypotheses. MATERIALS AND METHODS: T1-weighted volumetric images from 21 patients with KS and 16 matched control subjects were analyzed with optimized VBM. Images were segmented and spatially normalized, and these deformation parameters were then applied to the original images before the second segmentation. Patients were divided into groups with and without MM, and a t test statistic was then applied on a voxel-by-voxel basis between the groups and controls to evaluate significant differences. RESULTS: When considering our hypothesis a priori, we found that 2 areas of increased gray matter volume, in the left primary motor and sensorimotor cortex, were demonstrated only in patients with MM, when compared with healthy controls. Regarding white matter alterations, no areas of altered volume involving the corpus callosum or the projection of the corticospinal tract were demonstrated. CONCLUSION: The VBM study did not show significant white matter changes in patients with KS but showed gray matter alterations in keeping with a hypertrophic response to a deficient pyramidal decussation in patients with MM. In addition, gray matter alterations were observed in patients without MM, which can represent more complex mechanisms determining the presence or absence of this symptom.
Assuntos
Encéfalo/patologia , Lateralidade Funcional/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Síndrome de Kallmann/diagnóstico , Imageamento por Ressonância Magnética/métodos , Córtex Motor/patologia , Transtornos dos Movimentos/diagnóstico , Tratos Piramidais/patologia , Adolescente , Adulto , Criança , Corpo Caloso/patologia , Dominância Cerebral/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Inibição Neural/fisiologia , Exame Neurológico , Tamanho do Órgão/fisiologia , Córtex Somatossensorial/fisiologiaRESUMO
CONTEXT: Physiological activation of the prokineticin pathway has a critical role in olfactory bulb morphogenesis and GnRH secretion in mice. OBJECTIVE: To investigate PROK2 and PROKR2 mutations in patients with hypogonadotropic hypogonadism (HH) associated or not with olfactory abnormalities. DESIGN: We studied 107 Brazilian patients with HH (63 with Kallmann syndrome and 44 with normosmic HH) and 100 control individuals. The coding regions of PROK2 and PROKR2 were amplified by PCR followed by direct automatic sequencing. RESULTS: In PROK2, two known frameshift mutations were identified. Two brothers with Kallmann syndrome harbored the homozygous p.G100fsX121 mutation, whereas one male with normosmic HH harbored the heterozygous p.I55fsX56 mutation. In PROKR2, four distinct mutations (p.R80C, p.Y140X, p.L173R, and p.R268C) were identified in five patients with Kallmann syndrome and in one patient with normosmic HH. These mutations were not found in the control group. The p.R80C, p.L173R, and p.R268C missense mutations were identified in the heterozygous state in the HH patients and in their asymptomatic first-degree relatives. In addition, no mutations of FGFR1, KAL1, GnRHR, KiSS-1, or GPR54 were identified in these patients. Notably, the new nonsense mutation (p.Y140X) was identified in the homozygous state in an anosmic boy with micropenis, bilateral cryptorchidism, and high-arched palate. His asymptomatic parents were heterozygous for this severe defect. CONCLUSION: We expanded the repertoire of PROK2 and PROKR2 mutations in patients with HH. In addition, we show that PROKR2 haploinsufficiency is not sufficient to cause Kallmann syndrome or normosmic HH, whereas homozygous loss-of-function mutations either in PROKR2 or PROK2 are sufficient to cause disease phenotype, in accordance with the Prokr2 and Prok2 knockout mouse models.