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1.
Front Immunol ; 15: 1401962, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376563

RESUMO

Methylation, a key epigenetic modification, is essential for regulating gene expression and protein function without altering the DNA sequence, contributing to various biological processes, including gene transcription, embryonic development, and cellular functions. Methylation encompasses DNA methylation, RNA methylation and histone modification. Recent research indicates that DNA methylation is vital for establishing and maintaining normal brain functions by modulating the high-order structure of DNA. Alterations in the patterns of DNA methylation can exert significant impacts on both gene expression and cellular function, playing a role in the development of numerous diseases, such as neurological disorders, cardiovascular diseases as well as cancer. Our current understanding of the etiology of neurological diseases emphasizes a multifaceted process that includes neurodegenerative, neuroinflammatory, and neurovascular events. Epigenetic modifications, especially DNA methylation, are fundamental in the control of gene expression and are critical in the onset and progression of neurological disorders. Furthermore, we comprehensively overview the role and mechanism of DNA methylation in in various biological processes and gene regulation in neurological diseases. Understanding the mechanisms and dynamics of DNA methylation in neural development can provide valuable insights into human biology and potentially lead to novel therapies for various neurological diseases.


Assuntos
Metilação de DNA , Epigênese Genética , Doenças do Sistema Nervoso , Humanos , Doenças do Sistema Nervoso/genética , Animais , Regulação da Expressão Gênica
2.
RNA ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379106

RESUMO

Rett syndrome (RTT) is a neurodevelopmental disorder caused by loss-of-function mutations in the methyl CpG binding protein 2 (MECP2) gene. Despite its severe phenotype, studies in mouse models suggest that restoring MeCP2 levels can reverse RTT symptomology. Nevertheless, traditional gene therapy approaches are hindered by MECP2's narrow therapeutic window, complicating the safe delivery of viral constructs without overshooting the threshold for toxicity. The 3' untranslated region (3'UTR) plays a key role in gene regulation, where factors like miRNAs bind to pre-mRNA and fine-tune expression. Given that each miRNA's contribution is modest, blocking miRNA binding may represent a potential therapeutic strategy for diseases with high dosage sensitivity, like RTT. Here, we present a series of site-blocking antisense oligonucleotides (sbASOs) designed to outcompete repressive miRNA binding at the MECP2 3'UTR. This strategy aims to increase MECP2 levels in patients with missense or late-truncating mutations, where the hypomorphic nature of the protein can be offset by increased abundance. Our results demonstrate that sbASOs can elevate MECP2 levels in a dose-dependent manner in SH-SY5Y and patient fibroblast cell lines, plateauing at levels projected to be safe. Confirming in vivo functionality, sbASO administration in wild-type mice led to significant MeCP2 upregulation and the emergence of phenotypes associated with MeCP2 overexpression. In a T158M neural stem cell model of RTT, sbASO treatment significantly increased MECP2 expression and levels of the downstream effector protein, brain-derived neurotrophic factor (BDNF). These findings highlight the potential of sbASO-based therapies for MECP2-related disorders and advocate for their continued development.

3.
EMBO Mol Med ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39402139

RESUMO

Loss-of-function mutations in MECP2 are associated to Rett syndrome (RTT), a severe neurodevelopmental disease. Mainly working as a transcriptional regulator, MeCP2 absence leads to gene expression perturbations resulting in deficits of synaptic function and neuronal activity. In addition, RTT patients and mouse models suffer from a complex metabolic syndrome, suggesting that related cellular pathways might contribute to neuropathogenesis. Along this line, autophagy is critical in sustaining developing neuron homeostasis by breaking down dysfunctional proteins, lipids, and organelles.Here, we investigated the autophagic pathway in RTT and found reduced content of autophagic vacuoles in Mecp2 knock-out neurons. This correlates with defective lipidation of LC3B, probably caused by a deficiency of the autophagic membrane lipid phosphatidylethanolamine. The administration of the autophagy inducer trehalose recovers LC3B lipidation, autophagosomes content in knock-out neurons, and ameliorates their morphology, neuronal activity and synaptic ultrastructure. Moreover, we provide evidence for attenuation of motor and exploratory impairment in Mecp2 knock-out mice upon trehalose administration. Overall, our findings open new perspectives for neurodevelopmental disorders therapies based on the concept of autophagy modulation.

4.
Medicina (B Aires) ; 84 Suppl 3: 45-49, 2024 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-39331775

RESUMO

Rett Syndrome (RTT) is a neurodevelopment disorder which primarily affects females and is caused by pathogenic variants in the MECP2 gene. The disease has a characteristic developmental regression resulting in impairment of expressive language, hand skills, and ambulation that is accompanied by hand stereotypies. The goal of this article it to provide an overview of the diagnosis, natural history, and treatment.


El síndrome de Rett (SR) es un desorden del neurodesarrollo que afecta principalmente a mujeres y es causado por una variante patogénica en el gen MECP2. Esta enfermedad se caracteriza por una regresión del desarrollo que resulta en el deterioro del lenguaje expresivo, habilidades manuales, y deambulación, y está acompañado de estereotipias manuales. El objetivo de este artículo es proporcionar una visión general del diagnóstico, la historia natural y el tratamiento.


Assuntos
Proteína 2 de Ligação a Metil-CpG , Síndrome de Rett , Humanos , Síndrome de Rett/fisiopatologia , Síndrome de Rett/genética , Síndrome de Rett/terapia , Feminino , Proteína 2 de Ligação a Metil-CpG/genética , Mutação
5.
J Am Soc Mass Spectrom ; 35(10): 2308-2314, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39258941

RESUMO

Single-cell proteomics has emerged as a powerful technology for unraveling the complexities of cellular heterogeneity, enabling insights into individual cell functions and pathologies. One of the primary challenges in single-cell proteomics is data generation, where low mass spectral signals often preclude the triggering of MS2 events. This challenge is addressed by Data Independent Acquisition (DIA), a data acquisition strategy that does not depend on peptide ion isotopic signatures to generate an MS2 event. In this study, we present data generated from the integration of DIA single-cell proteomics with a version of the DiagnoMass Proteomic Hub that was adapted to handle DIA data. DiagnoMass employs a hierarchical clustering methodology that enables the identification of tandem mass spectral clusters that are discriminative of biological conditions, thereby reducing the reliance on search engine biases for identifications. Nevertheless, a search engine (in this work, DIA-NN) can be integrated with DiagnoMass for spectral annotation. We used single-cell proteomic data from iPSC-derived neuroprogenitor cell cultures as a test study of this integrated approach. We were able to differentiate between control and Rett Syndrome patient cells to discern the proteomic variances potentially contributing to the disease's pathology. Our research confirms that the DiagnoMass-DIA synergy significantly enhances the identification of discriminative proteomic signatures, highlighting critical biological variations such as the presence of unique spectra that could be related to Rett Syndrome pathology.


Assuntos
Proteômica , Análise de Célula Única , Espectrometria de Massas em Tandem , Humanos , Proteômica/métodos , Análise de Célula Única/métodos , Espectrometria de Massas em Tandem/métodos , Síndrome de Rett , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/química , Proteoma/análise , Ferramenta de Busca , Análise por Conglomerados
6.
Cell Mol Life Sci ; 81(1): 410, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305343

RESUMO

Rett syndrome (RTT) is a neurodevelopmental disorder caused by de novo mutations in the MECP2 gene. Although miRNAs in extracellular vesicles (EVs) have been suggested to play an essential role in several neurological conditions, no prior study has utilized brain organoids to profile EV-derived miRNAs during normal and RTT-affected neuronal development. Here we report the spatiotemporal expression pattern of EV-derived miRNAs in region-specific forebrain organoids generated from female hiPSCs with a MeCP2:R255X mutation and the corresponding isogenic control. EV miRNA and protein expression profiles were characterized at day 0, day 13, day 40, and day 75. Several members of the hsa-miR-302/367 cluster were identified as having a time-dependent expression profile with RTT-specific alterations at the latest developmental stage. Moreover, the miRNA species of the chromosome 14 miRNA cluster (C14MC) exhibited strong upregulation in RTT forebrain organoids irrespective of their spatiotemporal location. Together, our results suggest essential roles of the C14MC and hsa-miR-302/367 clusters in EVs during normal and RTT-associated neurodevelopment, displaying promising prospects as biomarkers for monitoring RTT progression.


Assuntos
Encéfalo , Vesículas Extracelulares , Proteína 2 de Ligação a Metil-CpG , MicroRNAs , Organoides , Síndrome de Rett , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Síndrome de Rett/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Humanos , Organoides/metabolismo , Organoides/patologia , Feminino , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Mutação , Prosencéfalo/metabolismo
7.
Pediatr Neurol ; 161: 28-33, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39255539

RESUMO

BACKGROUND: This study aimed to explore the clinical utility of targeted MECP2 testing in a large cohort of females with neurodevelopmental delays. Our aim was to identify suitable candidates for testing based on prevailing diagnostic criteria. METHODS: Eligible participants with global developmental delay/arrest or regression before age 36 months underwent MECP2 testing. MECP2-positive patients were further categorized based on Rett syndrome (RTT) diagnostic criteria, including typical, atypical, possible, and unclassified, to assess disease typicality and progression with respect to age. RESULTS: Of the 683 patients, 162 (23.7%) were diagnosed with MECP2-related RTT. Global developmental delay was the predominant initial symptom in approximately 75% of the cohort with developmental arrest/regression at testing. Symptoms emerged before age six months in 14 patients (8.6%). The average age at the time of MECP2 testing was 3.7 years, with 31.5% of the patients tested under two years. Of those under two years, 15 were initially categorized into the unclassified group; however, 12 were later reclassified into the typical/atypical RTT groups based on follow-up evaluation. Among the 119 patients monitored beyond age five years, 80% displayed typical RTT symptoms, 10 remained unclassified, and 9.8% had exonic deletions, posing challenges for detection using next-generation sequencing. CONCLUSIONS: Targeted MECP2 testing has emerged as a clinically valuable tool with a high diagnostic yield, including the identification of small deletions. Given that younger patients may not always meet the classic RTT criteria, this study recommends targeted MECP2 testing in younger patients without typical RTT features.

8.
Sci Rep ; 14(1): 20565, 2024 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232000

RESUMO

Studies on MECP2 function and its implications in Rett Syndrome (RTT) have traditionally centered on neurons. Here, using human embryonic stem cell (hESC) lines, we modeled MECP2 loss-of-function to explore its effects on astrocyte (AST) development and dysfunction in the brain. Ultrastructural analysis of RTT hESC-derived cerebral organoids revealed significantly smaller mitochondria compared to controls (CTRs), particularly pronounced in glia versus neurons. Employing a multiomics approach, we observed increased gene expression and accessibility of a subset of nuclear-encoded mitochondrial genes upon mutation of MECP2 in ASTs compared to neurons. Analysis of hESC-derived ASTs showed reduced mitochondrial respiration and altered key proteins in the tricarboxylic acid cycle and electron transport chain in RTT versus CTRs. Additionally, RTT ASTs exhibited increased cytosolic amino acids under basal conditions, which were depleted upon increased energy demands. Notably, mitochondria isolated from RTT ASTs exhibited increased reactive oxygen species and influenced neuronal activity when transferred to cortical neurons. These findings underscore MECP2 mutation's differential impact on mitochondrial and metabolic pathways in ASTs versus neurons, suggesting that dysfunctional AST mitochondria may contribute to RTT pathophysiology by affecting neuronal health.


Assuntos
Astrócitos , Proteína 2 de Ligação a Metil-CpG , Mitocôndrias , Mutação , Neurônios , Espécies Reativas de Oxigênio , Síndrome de Rett , Proteína 2 de Ligação a Metil-CpG/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Mitocôndrias/metabolismo , Astrócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Humanos , Neurônios/metabolismo , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Síndrome de Rett/patologia , Células-Tronco Embrionárias Humanas/metabolismo , Linhagem Celular
9.
Brain ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39300821

RESUMO

MECP2 deficiency causes a broad spectrum of neuropsychiatric disorders that can affect both genders. Rett syndrome is the most common and is characterized by an apparently normal growth period followed by a regression phase in which patients lose most of their previously acquired skills. After this dramatic period, various symptoms progressively appear, including severe intellectual disability, epilepsy, apraxia, breathing abnormalities and motor deterioration. MECP2 encodes for an epigenetic transcription factor that is particularly abundant in the brain; consequently, several transcriptional defects characterize the Rett syndrome brain. The well-known deficiency of several neurotrophins and growth factors, together with the positive effects exerted by Trofinetide, a synthetic analogue of insulin-like growth factor 1, in Rett patients and in mouse models of Mecp2 deficiency, prompted us to investigate the therapeutic potential of nerve growth factor. Initial in vitro studies demonstrated a healing effect of rhNGF on neuronal maturation and activity in cultured Mecp2-null neurons. Subsequently, we designed in vivo studies with clear translational potential using intranasally administered recombinant human GMP-grade NGF (rhNGF) already used in the clinic. Efficacy of rhNGF in vivo in Mecp2-null hemizygous male mice and heterozygous female mice was assessed. General well-being was evaluated by a conventional phenotypic score and motor performance through the Pole and Beam Walking tests, while cognitive function and interaction with the environment were measured by the Novel Object Recognition Test and the Marble Burying test, respectively. At the end of the treatment, mouse cortices were dissected and bulk RNA sequencing was performed to identify the molecular pathways involved in the protective effects of rhNGF. rhNGF exerted positive effects on cognitive and motor functions in both male and female mouse models of Rett syndrome. In male hemizygous mice, which suffer from significantly more severe and rapidly advancing symptoms, the drug's ability to slow the disease's progression was more pronounced. The unbiased research for the molecular mechanisms triggering the observed benefits revealed a strong positive effect on gene sets related to oxidative phosphorylation, mitochondrial structure and function. These results were validated by demonstrating the drug's ability to improve mitochondrial structure and respiration in Mecp2-null cerebral cortices. Furthermore, GO analyses indicated that NGF exerted the expected improvement in neuronal maturation. We conclude that intranasal administration of rhNGF is a non-invasive and effective route of administration for the treatment of Rett syndrome and possibly for other neurometabolic disorders with overt mitochondrial dysfunction.

10.
Mol Autism ; 15(1): 39, 2024 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300547

RESUMO

BACKGROUND: Defective mitochondria and aberrant brain mitochondrial bioenergetics are consistent features in syndromic intellectual disability disorders, such as Rett syndrome (RTT), a rare neurologic disorder that severely affects mainly females carrying mutations in the X-linked MECP2 gene. A pool of CB1 cannabinoid receptors (CB1R), the primary receptor subtype of the endocannabinoid system in the brain, is located on brain mitochondrial membranes (mtCB1R), where it can locally regulate energy production, synaptic transmission and memory abilities through the inhibition of the intra-mitochondrial protein kinase A (mtPKA). In the present study, we asked whether an overactive mtCB1R-mtPKA signaling might underlie the brain mitochondrial alterations in RTT and whether its modulation by systemic administration of the CB1R inverse agonist rimonabant might improve bioenergetics and cognitive defects in mice modeling RTT. METHODS: Rimonabant (0.3 mg/kg/day, intraperitoneal injections) was administered daily to symptomatic female mice carrying a truncating mutation of the Mecp2 gene and its effects on brain mitochondria functionality, systemic oxidative status, and memory function were assessed. RESULTS: mtCB1R is overexpressed in the RTT mouse brain. Subchronic treatment with rimonabant normalizes mtCB1R expression in RTT mouse brains, boosts mtPKA signaling, and restores the defective brain mitochondrial bioenergetics, abnormal peripheral redox homeostasis, and impaired cognitive abilities in RTT mice. LIMITATIONS: The lack of selectivity of the rimonabant treatment towards mtCB1R does not allow us to exclude that the beneficial effects exerted by the treatment in the RTT mouse model may be ascribed more broadly to the modulation of CB1R activity and distribution among intracellular compartments, rather than to a selective effect on mtCB1R-mediated signaling. The low sample size of few experiments is a further limitation that has been addressed replicating the main findings under different experimental conditions. CONCLUSIONS: The present data identify mtCB1R overexpression as a novel molecular alteration in the RTT mouse brain that may underlie defective brain mitochondrial bioenergetics and cognitive dysfunction.


Assuntos
Encéfalo , Modelos Animais de Doenças , Metabolismo Energético , Mitocôndrias , Receptor CB1 de Canabinoide , Síndrome de Rett , Rimonabanto , Animais , Feminino , Camundongos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Proteína 2 de Ligação a Metil-CpG/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Receptor CB1 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/antagonistas & inibidores , Síndrome de Rett/metabolismo , Síndrome de Rett/tratamento farmacológico , Síndrome de Rett/genética , Rimonabanto/farmacologia
11.
Mol Biol Rep ; 51(1): 979, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39269588

RESUMO

BACKGROUND: Rett syndrome (RTT) is a rare neurodevelopmental disorder that primarily affects females and is characterized by a period of normal development followed by severe cognitive, motor, and communication impairment. The syndrome is predominantly caused by mutations in the MECP2. This study aimed to use comprehensive multi-omic analysis to identify the molecular and metabolic alterations associated with Rett syndrome. METHODS AND RESULTS: Transcriptomic and metabolomic profiling was performed using neuron-like cells derived from the fibroblasts of 3 Rett syndrome patients with different MECP2 mutations (R168X, P152R, and R133C) and 1 healthy control. Differential gene expression, alternative splicing events, and metabolite changes were analyzed to identify the key pathways and processes affected in patients with Rett syndrome. Transcriptomic analysis showed there was significant down-regulation of genes associated with the extracellular matrix (ECM) and cytoskeletal components, which was particularly notable in patient P3 (R133C mutation), who had non-random X chromosome inactivation. Additionally, significant changes in microtubule-related gene expression and alternative splicing events were observed, especially in patient P2 (P152R mutation). Metabolomic profiling showed that there were alterations in metabolic pathways, particularly up-regulation of ketone body synthesis and degradation pathways, in addition to an increase in free fatty acid levels. Integrated analysis highlighted the interplay between structural gene down-regulation and metabolic shifts, underscoring the adaptive responses to cellular stress in Rett neurons. CONCLUSION: The present findings provide valuable insights into the molecular and metabolic landscape of Rett syndrome, emphasizing the importance of combining omic data to enlighten the molecular pathophysiology of this syndrome.


Assuntos
Proteína 2 de Ligação a Metil-CpG , Mutação , Neurônios , Síndrome de Rett , Transcriptoma , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Humanos , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Transcriptoma/genética , Feminino , Neurônios/metabolismo , Mutação/genética , Fibroblastos/metabolismo , Perfilação da Expressão Gênica/métodos , Metabolômica/métodos , Metaboloma
12.
Respir Physiol Neurobiol ; 328: 104314, 2024 10.
Artigo em Inglês | MEDLINE | ID: mdl-39117159

RESUMO

Rett syndrome (RTT) is an autism spectrum disorder caused by loss-of-function mutations in the methyl-CPG-binding protein 2 (Mecp2) gene. Frequent apneas and irregular breathing are prevalent in RTT, and also occur in rodent models of the disorder, including Mecp2Bird and Mecp2R168X mice. Sarizotan, a serotonin 5-HT1a and dopamine D2-like receptor agonist, reduces the incidence of apneas and irregular breathing in mouse models of RTT (Abdala et al., 2014). Targeting the 5HT1a receptor alone also improves respiration in RTT mice (Levitt et al., 2013). However, the contribution of D2-like receptors in correcting these respiratory disturbances remains untested. PAOPA, a dopamine D2-like receptor positive allosteric modulator, and quinpirole, a dopamine D2-like receptor orthosteric agonist, were used in conjunction with whole-body plethysmography to evaluate whether activation of D2-like receptors is sufficient to improve breathing disturbances in female heterozygous Mecp2Bird/+ and Mecp2R168X/+ mice. PAOPA did not significantly change apnea incidence or irregularity score in RTT mice. PAOPA also had no effect on the ventilatory response to hypercapnia (7 % CO2). In contrast, quinpirole reduced apnea incidence and irregularity scores and improved the hypercapnic ventilatory response in Mecp2R168X/+ and Mecp2Bird/+ mice, while also reducing respiratory rate. These results suggest that D2-like receptors could contribute to the positive effects of sarizotan in the correction of respiratory abnormalities in Rett syndrome. However, positive allosteric modulation of D2-like receptors alone was not sufficient to evoke these effects.


Assuntos
Modelos Animais de Doenças , Agonistas de Dopamina , Proteína 2 de Ligação a Metil-CpG , Quimpirol , Receptores de Dopamina D2 , Síndrome de Rett , Animais , Síndrome de Rett/tratamento farmacológico , Síndrome de Rett/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D2/agonistas , Agonistas de Dopamina/farmacologia , Feminino , Camundongos , Quimpirol/farmacologia , Proteína 2 de Ligação a Metil-CpG/genética , Respiração/efeitos dos fármacos , Camundongos Transgênicos , Regulação Alostérica/efeitos dos fármacos , Camundongos Endogâmicos C57BL
13.
Int J Mol Sci ; 25(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39125882

RESUMO

Neurotrophins and their receptors are distinctly expressed during brain development and play crucial roles in the formation, survival, and function of neurons in the nervous system. Among these molecules, brain-derived neurotrophic factor (BDNF) has garnered significant attention due to its involvement in regulating GABAergic system development and function. In this review, we summarize and compare the expression patterns and roles of neurotrophins and their receptors in both the developing and adult brains of rodents, macaques, and humans. Then, we focus on the implications of BDNF in the development and function of GABAergic neurons from the cortex and the striatum, as both the presence of BDNF single nucleotide polymorphisms and disruptions in BDNF levels alter the excitatory/inhibitory balance in the brain. This imbalance has different implications in the pathogenesis of neurodevelopmental diseases like autism spectrum disorder (ASD), Rett syndrome (RTT), and schizophrenia (SCZ). Altogether, evidence shows that neurotrophins, especially BDNF, are essential for the development, maintenance, and function of the brain, and disruptions in their expression or signaling are common mechanisms in the pathophysiology of brain diseases.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Neurônios GABAérgicos , Humanos , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Neurônios GABAérgicos/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Receptores de Fator de Crescimento Neural/genética , Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/genética , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/genética , Encéfalo/metabolismo , Encéfalo/crescimento & desenvolvimento
14.
Genes (Basel) ; 15(8)2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39202466

RESUMO

Although long-term survival in Rett syndrome (RTT) has been observed, limited information on older people with RTT exists. We hypothesized that increased longevity in RTT would be associated with genetic variants in MECP2 associated with milder severity, and that clinical features would not be static in older individuals. To address these hypotheses, we compared the distribution of MECP2 variants and clinical severity between younger individuals with Classic RTT (under 30 years old) and older individuals (over 30 years old). Contrary to expectation, enrichment of a severe MECP2 variant (R106W) was observed in the older cohort. Overall severity was not different between the cohorts, but specific clinical features varied between the cohorts. Overall severity from first to last visit increased in the younger cohort but not in the older cohort. While some specific clinical features in the older cohort were stable from the first to the last visit, others showed improvement or worsening. These data do not support the hypothesis that mild MECP2 variants or less overall severity leads to increased longevity in RTT but demonstrate that clinical features change with increasing age in adults with RTT. Additional work is needed to understand disease progression in adults with RTT.


Assuntos
Progressão da Doença , Proteína 2 de Ligação a Metil-CpG , Síndrome de Rett , Síndrome de Rett/genética , Síndrome de Rett/patologia , Humanos , Proteína 2 de Ligação a Metil-CpG/genética , Adulto , Feminino , Adolescente , Adulto Jovem , Masculino , Pessoa de Meia-Idade , Criança , Pré-Escolar , Idoso , Longevidade/genética , Estudos de Coortes , Mutação
15.
Orphanet J Rare Dis ; 19(1): 296, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138481

RESUMO

BACKGROUND: Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder associated with multiple neurologic impairments. Previous studies have shown challenges to the quality of life of individuals with RTT and their caregivers. However, instruments applied to quantify disease burden have not adequately captured the impact of these impairments on affected individuals and their families. Consequently, an international collaboration of stakeholders aimed at evaluating Burden of Illness (BOI) in RTT was organized. METHODS: Based on literature reviews and qualitative interviews with parents of children and adults with RTT, a caregiver questionnaire was constructed to evaluate 22 problems (inclusive of core characteristics, functional impairments, and comorbidities) often experienced with RTT, rated mainly with a 5-level Likert scale. The questionnaire was administered anonymously online to an international sample of 756 caregivers (predominantly parents) of girls and women with RTT. Descriptive statistics were used to identify problems of high frequency and impact on affected individuals and caregivers. Chi-square tests characterized the relationship between problem severity and impact responses, while nonparametric ANOVAs of raw and z-score adjusted scores identified agreement between severity and impact on individual and caregiver. Secondary inferential tests were used to determine the roles of age, clinical type, and country of residence on BOI in RTT. RESULTS: There was variability in reported frequency of problems, with the most prevalent, severe and impactful being those related to the core features of RTT (i.e., communication and fine and gross motor impairments). Chi-square analyses demonstrated interdependence between severity and impact responses, while ANOVAs showed that many problems had disproportionately greater impact than severity, either on affected individuals (e.g., hand stereotypies) or their caregivers (e.g., sleep difficulties, seizures, pain, and behavioral abnormalities). With certain exceptions (e.g., breath-holding, seizures), age, clinical type, or country of residence did not influence these BOI profiles. CONCLUSIONS: Our data demonstrate that core features and related impairments are particularly impactful in RTT. However, problems with mild severity can also have disproportionate impact on affected individuals and, particularly, on their caregivers. Future analyses will examine the role of factors such as treatment outcomes, healthcare services, and healthcare provider's perspectives, in these BOI profiles.


Assuntos
Cuidadores , Efeitos Psicossociais da Doença , Síndrome de Rett , Humanos , Cuidadores/psicologia , Feminino , Inquéritos e Questionários , Adulto , Masculino , Adolescente , Criança , Adulto Jovem , Qualidade de Vida , Pré-Escolar , Pessoa de Meia-Idade
16.
Front Med (Lausanne) ; 11: 1425038, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39135718

RESUMO

Rett syndrome (RTT) and Rett-like syndromes [i.e., CDKL5 deficiency disorder (CDD) and FOXG1-syndrome] represent rare yet profoundly impactful neurodevelopmental disorders (NDDs). The severity and complexity of symptoms associated with these disorders, including cognitive impairment, motor dysfunction, seizures and other neurological features significantly affect the quality of life of patients and families. Despite ongoing research efforts to identify potential therapeutic targets and develop novel treatments, current therapeutic options remain limited. Here the potential of drug repurposing (DR) as a promising avenue for addressing the unmet medical needs of individuals with RTT and related disorders is explored. Leveraging existing drugs for new therapeutic purposes, DR presents an attractive strategy, particularly suited for neurological disorders given the complexities of the central nervous system (CNS) and the challenges in blood-brain barrier penetration. The current landscape of DR efforts in these syndromes is thoroughly examined, with partiuclar focus on shared molecular pathways and potential common drug targets across these conditions.

17.
Curr Issues Mol Biol ; 46(8): 8424-8440, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39194714

RESUMO

Rett syndrome (RTT) is a paediatric neurodevelopmental disorder spanning four developmental stages. This multi-system disorder offers a unique window to explore genotype-phenotype relationships in a disease model. However, genetic prognosticators of RTT have limited clinical value due to the disorder's heterogeneity on multiple levels. This case report used a precision medicine approach to better understand the clinical phenotype of RTT twins with an identical pathogenic MECP2 mutation and discordant neurodevelopmental profiles. Targeted genotyping, objective physiological monitoring of heart rate variability (HRV) parameters, and clinical severity were assessed in a RTT twin pair (5 years 7 months old) with an identical pathogenic MECP2 mutation. Longitudinal assessment of autonomic HRV parameters was conducted using the Empatica E4 wristband device, and clinical severity was assessed using the RTT-anchored Clinical Global Impression Scale (RTT-CGI) and the Multi-System Profile of Symptoms Scale (MPSS). Genotype data revealed impaired BDNF function for twin A when compared to twin B. Twin A also had poorer autonomic health than twin B, as indicated by lower autonomic metrics (autonomic inflexibility). Hospitalisation, RTT-CGI-S, and MPSS subscale scores were used as measures of clinical severity, and these were worse in twin A. Treatment using buspirone shifted twin A from an inflexible to a flexible autonomic profile. This was mirrored in the MPSS scores, which showed a reduction in autonomic and cardiac symptoms following buspirone treatment. Our findings showed that a combination of a co-occurring rs6265 BDNF polymorphism, and worse autonomic and clinical profiles led to a poorer prognosis for twin A compared to twin B. Buspirone was able to shift a rigid autonomic profile to a more flexible one for twin A and thereby prevent cardiac and autonomic symptoms from worsening. The clinical profile for twin A represents a departure from the disorder trajectory typically observed in RTT and underscores the importance of wider genotype profiling and longitudinal objective physiological monitoring alongside measures of clinical symptoms and severity when assessing genotype-phenotype relationships in RTT patients with identical pathogenic mutations. A precision medicine approach that assesses genetic and physiological risk factors can be extended to other neurodevelopmental disorders to monitor risk when genotype-phenotype relationships are not so obvious.

18.
Front Cell Dev Biol ; 12: 1413248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39108836

RESUMO

Rare neurological diseases include a vast group of heterogenous syndromes with primary impairment(s) in the peripheral and/or central nervous systems. Such rare disorders may have overlapping phenotypes, despite their distinct genetic etiology. One unique aspect of rare neurological diseases is their potential common association with altered epigenetic mechanisms. Epigenetic mechanisms include regulatory processes that control gene expression and cellular phenotype without changing the composition of the corresponding DNA sequences. Epigenetic factors include three types of proteins, the "readers, writers, and erasers" of DNA and DNA-bound proteins. Thus, epigenetic impairments of many neurological diseases may contribute to their pathology and manifested phenotypes. Here, we aim to provide a comprehensive review on the general etiology of selected rare neurological diseases, that include Rett Syndrome, Prader-Willi Syndrome, Rubinstein-Taybi Syndrome, Huntington's disease, and Angelman syndrome, with respect to their associated aberrant epigenetic mechanisms.

19.
Med ; 5(10): 1275-1281.e2, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39025065

RESUMO

BACKGROUND: Trofinetide was approved for the treatment of Rett syndrome (RTT) in patients aged ≥2 years based on the results of the 12-week, randomized, phase 3 LAVENDER study. In LILAC, a 40-week, open-label extension study of LAVENDER, trofinetide continued to improve the symptoms of RTT, with a similar safety profile as LAVENDER. Here, we report long-term safety and efficacy results of LILAC-2, a 32-month, open-label extension study. METHODS: Females aged 5-22 years who completed LILAC were eligible to enter LILAC-2. Safety and tolerability were assessed with the incidence of adverse events (AEs). Efficacy was assessed with Rett Syndrome Behaviour Questionnaire (RSBQ) and Clinical Global Impression-Improvement (CGI-I) scores. Caregiver interviews explored the patient's experience with RTT and the efficacy of trofinetide during study participation. FINDINGS: In total, 77 participants were enrolled in LILAC-2. The most common AEs were diarrhea (53.2%), COVID-19 (27.3%), and vomiting (19.5%). The mean (standard error [SE]) change in RSBQ score from LAVENDER baseline to week 104 of LILAC-2 was -11.8 (2.45). The mean (SE) CGI-I score from LILAC baseline to week 12 of LILAC-2 was 3.1 (0.10). Most caregivers (96%; n = 24/25) were satisfied or very satisfied with the benefits of trofinetide. CONCLUSIONS: Long-term treatment with trofinetide continued to improve RTT symptoms, without new safety concerns. Caregivers reported satisfaction with trofinetide related to improvements that were meaningful for their child and themselves. FUNDING: The study was supported by Acadia Pharmaceuticals (San Diego, CA, USA). This study was registered at ClinicalTrials.gov: NCT04776746.


Assuntos
Síndrome de Rett , Humanos , Feminino , Síndrome de Rett/tratamento farmacológico , Adolescente , Criança , Adulto Jovem , Pré-Escolar , Resultado do Tratamento
20.
J Neurodev Disord ; 16(1): 42, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39061009

RESUMO

BACKGROUND: With the advent of the first targeted therapy for Rett Syndrome (RTT), a comprehensive assessment of the journey of RTT is needed to elucidate on present unmet needs in this population. This study characterized females with RTT in the United States and their disease journey with respect to longitudinal treatment patterns, RTT-related outcomes, and changes in disease severity. METHODS: This retrospective cohort study used registry data of females with RTT from the 5211 RTT Natural History Study (RNHS) (November 2015-July 2021). Pharmacological and supportive therapy use, RTT-related outcomes, and RTT severity, as measured by the Clinical Severity Scale and Motor Behavioral Assessment scale, were evaluated following the first RNHS visit. Analyses were conducted overall and in subgroups by RTT type (classic and atypical RTT) and age at first visit (pediatric and adult). RESULTS: A total of 455 females with RTT were included in the study, of whom 90.5% had classic RTT and 79.8% were pediatric individuals. Over a median follow-up of 4 years, use of pharmacological therapies, including prokinetic agents (42.7% vs. 28.3%), and supportive therapies, including physical therapy (87.3% vs. 40.2%) and speech-language therapy (86.8% vs. 23.9%), were more common in pediatric than adult individuals (all p < 0.05). Nearly half (44.6%) of all individuals had a hospital or emergency room visit, with a higher proportion of visits in individuals with classic RTT than atypical RTT and pediatric than adult individuals (both p = 0.001). An increasing trend in clinical severity was observed in pediatric individuals (mean change per year: 0.24; 95% confidence interval [CI]: 0.03, 0.44), while an increasing trend in motor-behavioral dysfunction was observed in pediatric individuals (mean change per year: 1.12; 95% CI: 0.63, 1.60) and those with classic RTT (mean change per year: 0.97; 95% CI: 0.53, 1.41). CONCLUSIONS: Findings from this study highlight the considerable burden of RTT across disease subtype and age. Despite reliance on supportive therapies and healthcare encounters, individuals with RTT experience increasing disease severity and motor-behavioral dysfunction in childhood and adolescence, underscoring the unmet needs of this population and the value of early intervention to manage RTT in the long-term.


Assuntos
Síndrome de Rett , Humanos , Síndrome de Rett/fisiopatologia , Síndrome de Rett/terapia , Síndrome de Rett/complicações , Feminino , Estados Unidos/epidemiologia , Adulto , Criança , Adolescente , Estudos Retrospectivos , Adulto Jovem , Pré-Escolar , Índice de Gravidade de Doença , Sistema de Registros , Lactente , Bases de Dados Factuais
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