ANA CLAUDIA LATRONICO XAVIER
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Clínica Médica, Faculdade de Medicina - Docente
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
15 resultados
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Agora exibindo 1 - 10 de 15
- Genotype-Phenotype Correlations in Central Precocious Puberty Caused by MKRN3 Mutations (vol 106, pg 1041, 2021)(2021) SERAPHIM, C. E.; CANTON, A. P. M.; MONTENEGRO, L.; PIOVESAN, M. R.; MACEDO, D. B.; CUNHA, M.; GUIMARAES, A.; RAMOS, C. O.; BENEDETTI, A. F. F.; LEAL, De Castro A.; GAGLIARDI, P. C.; ANTONINI, S. R.; GRYNGARTEN, M.; ARCARI, A. J.; ABREU, A. P.; KAISER, U. B.; SORIANO-GUILLEN, L.; ESCRIBANO-MUNOZ, A.; CORRIPIO, R.; I, J. Labarta; TRAVIESO-SUAREZ, L.; V, N. Ortiz-Cabrera; ARGENTE, J.; MENDONCA, B. B.; BRITO, V. N.; LATRONICO, A. C.
- The Congenital and Acquired Mechanisms Implicated in the Etiology of Central Precocious Puberty(2023) BRITO, Vinicius N.; CANTON, Ana P. M.; SERAPHIM, Carlos Eduardo; ABREU, Ana Paula; MACEDO, Delanie B.; MENDONCA, Berenice B.; KAISER, Ursula B.; ARGENTE, Jesus; LATRONICO, Ana ClaudiaThe etiology of central precocious puberty (CPP) is multiple and heterogeneous, including congenital and acquired causes that can be associated with structural or functional brain alterations. All causes of CPP culminate in the premature pulsatile secretion of hypothalamic GnRH and, consequently, in the premature reactivation of hypothalamic-pituitary-gonadal axis. The activation of excitatory factors or suppression of inhibitory factors during childhood represent the 2 major mechanisms of CPP, revealing a delicate balance of these opposing neuronal pathways. Hypothalamic hamartoma (HH) is the most well-known congenital cause of CPP with central nervous system abnormalities. Several mechanisms by which hamartoma causes CPP have been proposed, including an anatomical connection to the anterior hypothalamus, autonomous neuroendocrine activity in GnRH neurons, trophic factors secreted by HH, and mechanical pressure applied to the hypothalamus. The importance of genetic and/or epigenetic factors in the underlying mechanisms of CPP has grown significantly in the last decade, as demonstrated by the evidence of genetic abnormalities in hypothalamic structural lesions (eg, hamartomas, gliomas), syndromic disorders associated with CPP (Temple, Prader-Willi, Silver-Russell, and Rett syndromes), and isolated CPP from monogenic defects (MKRN3 and DLK1 loss-of-function mutations). Genetic and epigenetic discoveries involving the etiology of CPP have had influence on the diagnosis and familial counseling providing bases for potential prevention of premature sexual development and new treatment targets in the future. Global preventive actions inducing healthy lifestyle habits and less exposure to endocrine-disrupting chemicals during the lifespan are desirable because they are potentially associated with CPP.
- Prevalence of Deleterious Variants in MC3R in Patients With Constitutional Delay of Growth and Puberty(2023) DUCKETT, Katie; WILLIAMSON, Alice; KINCAID, John W. R.; RAINBOW, Kara; CORBIN, Laura J.; MARTIN, Hilary C.; EBERHARDT, Ruth Y.; HUANG, Qin Qin; HURLES, Matthew E.; HE, Wen; BRAUNER, Raja; DELANEY, Angela; DUNKEL, Leo; GRINSPON, Romina P.; HALL, Janet E.; HIRSCHHORN, Joel N.; HOWARD, Sasha R.; LATRONICO, Ana C.; JORGE, Alexander A. L.; MCELREAVEY, Ken; MERICQ, Veronica; MERINO, Paulina M.; PALMERT, Mark R.; PLUMMER, Lacey; REY, Rodolfo A.; REZENDE, Raissa C.; SEMINARA, Stephanie B.; SALNIKOV, Kathryn; BANERJEE, Indraneel; LAM, Brian Y. H.; PERRY, John R. B.; TIMPSON, Nicholas J.; CLAYTON, Peter; CHAN, Yee-Ming; ONG, Ken K.; O'RAHILLY, StephenContext The melanocortin 3 receptor (MC3R) has recently emerged as a critical regulator of pubertal timing, linear growth, and the acquisition of lean mass in humans and mice. In population-based studies, heterozygous carriers of deleterious variants in MC3R report a later onset of puberty than noncarriers. However, the frequency of such variants in patients who present with clinical disorders of pubertal development is currently unknown. Objective This work aimed to determine whether deleterious MC3R variants are more frequently found in patients clinically presenting with constitutional delay of growth and puberty (CDGP) or normosmic idiopathic hypogonadotropic hypogonadism (nIHH). Methods We examined the sequence of MC3R in 362 adolescents with a clinical diagnosis of CDGP and 657 patients with nIHH, experimentally characterized the signaling properties of all nonsynonymous variants found and compared their frequency to that in 5774 controls from a population-based cohort. Additionally, we established the relative frequency of predicted deleterious variants in individuals with self-reported delayed vs normally timed menarche/voice-breaking in the UK Biobank cohort. Results MC3R loss-of-function variants were infrequent but overrepresented in patients with CDGP (8/362 [2.2%]; OR = 4.17; P = .001). There was no strong evidence of overrepresentation in patients with nIHH (4/657 [0.6%]; OR = 1.15; P = .779). In 246 328 women from the UK Biobank, predicted deleterious variants were more frequently found in those self-reporting delayed (aged & GE;16 years) vs normal age at menarche (OR = 1.66; P = 3.90E-07). Conclusion We have found evidence that functionally damaging variants in MC3R are overrepresented in individuals with CDGP but are not a common cause of this phenotype.
- Clinical and Genetic Characterization of Familial Central Precocious Puberty(2023) TINANO, Flavia Rezende; CANTON, Ana Pinheiro Machado; MONTENEGRO, Luciana R.; LEAL, Andrea de Castro; FARIA, Aline G.; SERAPHIM, Carlos E.; BRAUNER, Raja; JORGE, Alexander A.; MENDONCA, Berenice B.; ARGENTE, Jesus; BRITO, Vinicius N.; LATRONICO, Ana ClaudiaContext Central precocious puberty (CPP) can have a familial form in approximately one-quarter of the children. The recognition of this inherited condition increased after the identification of autosomal dominant CPP with paternal transmission caused by mutations in the MKRN3 and DLK1 genes. Objective We aimed to characterize the inheritance and estimate the prevalence of familial CPP in a large multiethnic cohort; to compare clinical and hormonal features, as well as treatment response to GnRH analogs (GnRHa), in children with distinct modes of transmission; and to investigate the genetic basis of familial CPP. Methods We retrospectively studied 586 children with a diagnosis of CPP. Patients with familial CPP (n = 276) were selected for clinical and genetic analysis. Data from previous studies were grouped, encompassing sequencing of MKRN3 and DLK1 genes in 204 patients. Large-scale parallel sequencing was performed in 48 individuals from 34 families. Results The prevalence of familial CPP was estimated at 22%, with a similar frequency of maternal and paternal transmission. Pedigree analyses of families with maternal transmission suggested an autosomal dominant inheritance. Clinical and hormonal features, as well as treatment response to GnRHa, were similar among patients with different forms of transmission of familial CPP. MKRN3 loss-of-function mutations were the most prevalent cause of familial CPP, followed by DLK1 loss-of-function mutations, affecting, respectively, 22% and 4% of the studied families; both affected exclusively families with paternal transmission. Rare variants of uncertain significance were identified in CPP families with maternal transmission. Conclusion We demonstrated a similar prevalence of familial CPP with maternal and paternal transmission. MKRN3 and DLK1 loss-of-function mutations were the major causes of familial CPP with paternal transmission.
- Novel MKRN3 Missense Mutations Associated With Central Precocious Puberty Reveal Distinct Effects on Ubiquitination(2023) MAGNOTTO, John C.; MANCINI, Alessandra; BIRD, Keisha; MONTENEGRO, Luciana; TUTUNCULER, Filiz; PEREIRA, Sidney A.; SIMAS, Vitoria; GARCIA, Leonardo; ROBERTS, Stephanie A.; MACEDO, Delanie; MAGNUSON, Melissa; GAGLIARDI, Priscila; MAURAS, Nelly; WITCHEL, Selma F.; CARROLL, Rona S.; LATRONICO, Ana Claudia; KAISER, Ursula B.; ABREU, Ana PaulaContext Loss-of-function mutations in the maternally imprinted genes, MKRN3 and DLK1, are associated with central precocious puberty (CPP). Mutations in MKRN3 are the most common known genetic etiology of CPP. Objective This work aimed to screen patients with CPP for MKRN3 and DLK1 mutations and analyze the effects of identified mutations on protein function in vitro. Methods Participants included 84 unrelated children with CPP (79 girls, 5 boys) and, when available, their first-degree relatives. Five academic medical institutions participated. Sanger sequencing of MKRN3 and DLK1 5 ' upstream flanking and coding regions was performed on DNA extracted from peripheral blood leukocytes. Western blot analysis was performed to assess protein ubiquitination profiles. Results Eight heterozygous MKRN3 mutations were identified in 9 unrelated girls with CPP. Five are novel missense mutations, 2 were previously identified in patients with CPP, and 1 is a frameshift variant not previously associated with CPP. No pathogenic variants were identified in DLK1. Girls with MKRN3 mutations had an earlier age of initial pubertal signs and higher basal serum luteinizing hormone and follicle-stimulating hormone compared to girls with CPP without MRKN3 mutations. Western blot analysis revealed that compared to wild-type MKRN3, mutations within the RING finger domain reduced ubiquitination whereas the mutations outside this domain increased ubiquitination. Conclusion MKRN3 mutations were present in 10.7% of our CPP cohort, consistent with previous studies. The novel identified mutations in different domains of MKRN3 revealed different patterns of ubiquitination, suggesting distinct molecular mechanisms by which the loss of MRKN3 results in early pubertal onset.
- Intra-individual Variability of Serum Aldosterone and Implications for Primary Aldosteronism Screening(2023) MACIEL, Ana Alice W.; FREITAS, Thais C.; FAGUNDES, Gustavo F. C.; PETENUCI, Janaina; VILELA, Leticia A. P.; BRITO, Luciana P.; GOLDBAUM, Tatiana S.; ZERBINI, Maria Claudia N.; LEDESMA, Felipe L.; TANNO, Fabio Y.; SROUGI, Victor; CHAMBO, Jose L.; PEREIRA, Maria Adelaide A.; COELHO, Fernando M. A.; CAVALCANTE, Aline C. B. S.; CARNEVALE, Francisco C.; PILAN, Bruna; PIO-ABREU, Andrea; V, Joao Silveira; CONSOLIM-COLOMBO, Fernanda M.; BORTOLOTTO, Luiz A.; LATRONICO, Ana Claudia; V, Maria Candida B. Fragoso; DRAGER, Luciano F.; MENDONCA, Berenice B.; ALMEIDA, Madson Q.Context Primary aldosteronism (PA) screening relies on an elevated aldosterone to renin ratio with a minimum aldosterone level, which varies from 10 to 15 ng/dL (277-415.5 pmol/L) using immunoassay. Objective To evaluate intra-individual coefficient of variation (CV) of aldosterone and aldosterone to direct renin concentration ratio (A/DRC) and its impact on PA screening. Methods A total of 671 aldosterone and DRC measurements were performed by the same chemiluminescence assays in a large cohort of 216 patients with confirmed PA and at least 2 screenings. Results The median intra-individual CV of aldosterone and A/DRC was 26.8% and 26.7%. Almost 40% of the patients had at least one aldosterone level <15 ng/dL, 19.9% had at least 2 aldosterone levels <15 ng/dL, and 16.2% had mean aldosterone levels <15 ng/dL. A lower cutoff of 10 ng/dL was associated with false negative rates for PA screening of 14.3% for a single aldosterone measurement, 4.6% for 2 aldosterone measurements, and only 2.3% for mean aldosterone levels. Considering the minimum aldosterone, true positive rate of aldosterone thresholds was 85.7% for 10 ng/dL and 61.6% for 15 ng/dL. An A/DRC >2 ng/dL/mu IU/mL had a true positive rate for PA diagnosis of 94.4% and 98.4% when based on 1 or 2 assessments, respectively. CV of aldosterone and A/DRC were not affected by sex, use of interfering antihypertensive medications, PA lateralization, hypokalemia, age, and number of hormone measurements. Conclusion Aldosterone concentrations had a high CV in PA patients, which results in an elevated rate of false negatives in a single screening for PA. Therefore, PA screening should be based on at least 2 screenings with concomitant aldosterone and renin measurements.
- Intra-individual Variability of Serum Aldosterone and Implications for Primary Aldosteronism Screening (Nov, dgac679, 2022)(2023) MACHEI, A. A. W.; FREITAS, T. C.; FAGUNDES, G. F. C.; PETENUCI, J.; VILELA, L. A. P.; BRITO, L. P.; GOLDBAUM, T. S.; ZERBINI, M. C. N.; LEDESMA, F. L.; YANNO, F. Y.; SROUGI, V; CHAMBO, J. L.; PEREIRA, M. A. A.; COELHO, F. M. A.; CAVALCANTE, A. C. B. S.; CARNEVALE, F. C.; PILAN, B.; PIO-ABREU, A.; V, J. Silveira; CONSOLIM-COLOMBO, F. M.; BORTOLOTTO, L. A.; LATRONICO, A. C.; V, M. C. B. Fragoso; DRAGER, L. F.; MENDONCA, B. B.; ALMEIDA, M. Q.
- SIN3A defects associated with syndromic congenital hypogonadotropic hypogonadism: an overlap with Witteveen-Kolk syndrome(2023) SCHNOLL, Caroline; KREPISCHI, Ana Cristina Victorino; RENCK, Alessandra Covallero; AMATO, Lorena Guimaraes Lima; KULIKOWSKI, Leslie Domenici; DANTAS, Naiara Castelo Branco; COSTA, Elaine Maria Frade; MENDONCA, Berenice Bilharinho; LATRONICO, Ana Claudia; JORGE, Alexander Augusto de Lima; SILVEIRA, Leticia Ferreira GontijoIntroduction: Congenital hypogonadotropic hypogonadism (CHH) is a rare condition caused by GnRH deficiency. More than 40 genes have been associated with the pathogenesis of CHH, but most cases still remain without a molecular diagnosis. Mutations involving the same gene (e.g. FGFR1, PROK2/PROKR2, CHD7) were found to cause normosmic CHH and Kallmann syndrome, with and without associated phenotypes, illustrating the coexistence of CHH with signs of other complex syndromes. The Witteveen-Kolk syndrome (WITKOS), caused by defects of the SIN3A gene, is a heterogeneous disorder characterized by distinctive facial features, microcephaly, short stature, delayed cognitive and motor development. Although micropenis and cryptorchidism have been reported in this syndrome, WITKOS has not been formally associated with CHH so far. Patients and Methods: A man with Kallmann syndrome (KS) associated with mild syndromic features (S1) and a boy with global developmental delay, syndromic short stature, micropenis and cryptorchidism (S2), in whom common genetic defects associated with CHH and short stature had been previously excluded, were studied by either chromosomal microarray analysis (CMA) or whole exome sequencing (WES). Results: Rare SIN3A pathogenic variants were identified in these two unrelated patients with CHH phenotypic features. A 550 kb deletion at 15q24.1, including the whole SIN3A gene, was identified in S1, and a SIN3A nonsense rare variant (p.Arg471*) was detected in S2. Conclusion: These findings lead us to propose a link between SIN3A defects and CHH, especially in syndromic cases, based on these two patients with overlapping phenotypes of WITKOS and CHH.
- Familial central precocious puberty due to DLK1 deficiency: novel genetic findings and relevance of serum DLK1 levels(2023) MONTENEGRO, Luciana; SERAPHIM, Carlos; TINANO, Flavia; PIOVESAN, Maiara; CANTON, Ana P. M.; MCELREAVEY, Ken; BRABANT, Severine; BORIS, Natalia P.; MAGNUSON, Melissa; CARROLL, Rona S.; KAISER, Ursula B.; ARGENTE, Jesus; BARRIOS, Vicente; BRITO, Vinicius N.; BRAUNER, Raja; LATRONICO, Ana ClaudiaBackground: Several rare loss-of-function mutations of delta-like noncanonical notch ligand 1 (DLK1) have been described in non-syndromic children with familial central precocious puberty (CPP). Objective: We investigated genetic abnormalities of DLK1 gene in a French cohort of children with idiopathic CPP. Additionally, we explored the pattern of DLK1 serum levels in patients with CPP and in healthy children at puberty, as well as in wild-type female mice. Patients and Methods: Genomic DNA was obtained from 121 French index cases with CPP. Automated sequencing of the coding region of the DLK1 gene was performed in all cases. Serum DLK1 levels were measured by enzyme linked immunosorbent assay (ELISA) in 209 individuals, including 191 with normal pubertal development and in female mice during postnatal pubertal maturation. Results: We identified 2 rare pathogenic DLK1 allelic variants: A stop gain variant (c.372C>A; p.Cys124X) and a start loss variant (c.2T>G; p.Met1?, or p.0) in 2 French girls with CPP. Mean serum DLK1 levels were similar between healthy children and idiopathic CPP children. In healthy individuals, DLK1 levels correlated with pubertal stage: In girls, DLK1 decreased between Tanner stages III and V, whereas in boys, DLK1 decreased between Tanner stages II and V (P =.008 and.016, respectively). Serum levels of Dlk1 also decreased in wild-type female mice. Conclusions: Novel loss-of-function mutations in DLK1 gene were identified in 2 French girls with CPP. Additionally, we demonstrated a pattern of dynamic changes in circulating DLK1 serum levels in humans and mice during pubertal stages, reinforcing the role of this factor in pubertal timing.
- Molecular basis of normal and pathological puberty: from basic mechanisms to clinical implications(2023) ARGENTE, Jesus; DUNKEL, Leo; KAISER, Ursula B.; LATRONICO, Ana C.; LOMNICZI, Alejandro; SORIANO-GUILLEN, Leandro; TENA-SEMPERE, ManuelPuberty is a major maturational event; its mechanisms and timing are driven by genetic determinants, but also controlled by endogenous and environmental cues. Substantial progress towards elucidation of the neuroendocrine networks governing puberty has taken place. However, key aspects of the mechanisms responsible for the precise timing of puberty and its alterations have only recently begun to be deciphered, propelled by epidemiological data suggesting that pubertal timing is changing in humans, via mechanisms that are not yet understood. By integrating basic and clinical data, we provide a comprehensive overview of current advances on the physiological basis of puberty, with a particular focus on the roles of kisspeptins and other central transmitters, the underlying molecular and endocrine mechanisms, and the pathways involved in pubertal modulation by nutritional and metabolic cues. Additionally, we have summarised molecular features of precocious and delayed puberty in both sexes, as revealed by clinical and genetic studies. This Review is a synoptic up-to-date view of how puberty is controlled and of the pathogenesis of major pubertal alterations, from both a clinical and translational perspective. We also highlight unsolved challenges that will seemingly concentrate future research efforts in this active domain of endocrinology.