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1.
Res Sq ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38746402

RESUMO

Background X-linked Dystonia-Parkinsonism(XDP) is an adult-onset neurodegenerative disorder that results in the loss of striatal medium spiny neurons (MSNs). XDP is associated with disease-specific mutations in and around the TAF1 gene. This study highlights the utility of directly reprogrammed MSNs from fibroblasts of affected XDP individuals as a platform that captures cellular and epigenetic phenotypes associated with XDP-related neurodegeneration. In addition, the current study demonstrates the neuroprotective effect of SAK3 currently tested in other neurodegenerative diseases. Methods XDP fibroblasts from three independent patients as well as age- and sex-matched control fibroblasts were used to generate MSNs by direct neuronal reprogramming using miRNA-9/9*-124 and thetranscription factors CTIP2 , DLX1 -P2A- DLX2 , and MYT1L . Neuronal death, DNA damage, and mitochondrial health assays were carried out to assess the neurodegenerative state of directly reprogrammed MSNs from XDP patients (XDP-MSNs). RNA sequencing and ATAC sequencing were performed to infer changes in the transcriptomic and chromatin landscapesof XDP-MSNs compared to those of control MSNs (Ctrl-MSNs). Results Our results show that XDP patient fibroblasts can be successfully reprogrammed into MSNs and XDP-MSNs display several degenerative phenotypes, including neuronal death, DNA damage, and mitochondrial dysfunction, compared to Ctrl-MSNs reprogrammed from age- and sex-matched control individuals' fibroblasts. In addition, XDP-MSNs showed increased vulnerability to TNFα -toxicity compared to Ctrl-MSNs. To dissect the altered cellular state in XDP-MSNs, we conducted transcriptomic and chromatin accessibility analyses using RNA- and ATAC-seq. Our results indicate that pathways related to neuronal function, calcium signaling, and genes related to other neurodegenerative diseases are commonly altered in XDP-MSNs from multiple patients. Interestingly, we found that SAK3, a T-type calcium channel activator, that may have therapeutic values in other neurodegenerative disorders, protected XDP-MSNs from neuronal death. Notably, we found that SAK3-mediated alleviation of neurodegeneration in XDP-MSNs was accompanied by gene expression changes toward Ctrl-MSNs.

2.
Cell Stem Cell ; 29(6): 918-932.e8, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35659876

RESUMO

Tau is a microtubule-binding protein expressed in neurons, and the equal ratios between 4-repeat (4R) and 3-repeat (3R) isoforms are maintained in normal adult brain function. Dysregulation of 3R:4R ratio causes tauopathy, and human neurons that recapitulate tau isoforms in health and disease will provide a platform for elucidating pathogenic processes involving tau pathology. We carried out extensive characterizations of tau isoforms expressed in human neurons derived by microRNA-induced neuronal reprogramming of adult fibroblasts. Transcript and protein analyses showed that miR neurons expressed all six isoforms with the 3R:4R isoform ratio equivalent to that detected in human adult brains. Also, miR neurons derived from familial tauopathy patients with a 3R:4R ratio altering mutation showed increased 4R tau and the formation of insoluble tau with seeding activity. Our results collectively demonstrate the utility of miRNA-induced neuronal reprogramming to recapitulate endogenous tau regulation comparable with the adult brain in health and disease.


Assuntos
MicroRNAs , Tauopatias , Adulto , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neurônios/metabolismo , Isoformas de Proteínas/metabolismo , Tauopatias/metabolismo , Tauopatias/patologia , Proteínas tau/metabolismo
3.
Methods Mol Biol ; 2239: 77-100, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33226614

RESUMO

MicroRNAs (miRNAs), miR-9/9*, and miR-124 (miR-9/9*-124) display fate-reprogramming activities when ectopically expressed in human fibroblasts by erasing the fibroblast identity and evoking a pan-neuronal state. In contrast to induced pluripotent stem cell-derived neurons, miRNA-induced neurons (miNs) retain the biological age of the starting fibroblasts through direct fate conversion and thus provide a human neuron-based platform to study cellular properties inherent in aged neurons and model adult-onset neurodegenerative disorders using patient-derived cells. Furthermore, expression of neuronal subtype-specific transcription factors in conjunction with miR-9/9*-124 guides the miNs to distinct neuronal fates, a feature critical for modeling disorders that affect specific neuronal subtypes. Here, we describe the miR-9/9*-124-based neuronal reprogramming protocols for the generation of several disease-relevant neuronal subtypes: striatal medium spiny neurons, cortical neurons, and spinal cord motor neurons.


Assuntos
Reprogramação Celular/genética , MicroRNAs/metabolismo , Neurônios Motores/citologia , Neurogênese/genética , Fatores de Transcrição/metabolismo , Linhagem Celular , Células Cultivadas , Senescência Celular/genética , Corpo Estriado/citologia , Corpo Estriado/metabolismo , Meios de Cultura/química , Fibroblastos/citologia , Fibroblastos/metabolismo , Vetores Genéticos , Humanos , Lentivirus/genética , MicroRNAs/genética , Neurônios Motores/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Medula Espinal/citologia , Medula Espinal/metabolismo , Fatores de Transcrição/genética
4.
Elife ; 92020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32851975

RESUMO

Retinoic acid-related orphan receptor beta (RORß) is a transcription factor (TF) and marker of layer 4 (L4) neurons, which are distinctive both in transcriptional identity and the ability to form aggregates such as barrels in rodent somatosensory cortex. However, the relationship between transcriptional identity and L4 cytoarchitecture is largely unknown. We find RORß is required in the cortex for L4 aggregation into barrels and thalamocortical afferent (TCA) segregation. Interestingly, barrel organization also degrades with age in wildtype mice. Loss of RORß delays excitatory input and disrupts gene expression and chromatin accessibility, with down-regulation of L4 and up-regulation of L5 genes, suggesting a disruption in cellular specification. Expression and binding site accessibility change for many other TFs, including closure of neurodevelopmental TF binding sites and increased expression and binding capacity of activity-regulated TFs. Lastly, a putative target of RORß, Thsd7a, is down-regulated without RORß, and Thsd7a knock-out alone disrupts TCA organization in adult barrels.


Assuntos
Neurônios , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares , Córtex Somatossensorial , Animais , Antígenos de Superfície/química , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Feminino , Masculino , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Neurônios/química , Neurônios/citologia , Neurônios/metabolismo , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/química , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Córtex Somatossensorial/química , Córtex Somatossensorial/citologia , Córtex Somatossensorial/metabolismo , Córtex Somatossensorial/fisiologia , Tálamo/química , Tálamo/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/genética
5.
Autism ; 23(5): 1096-1105, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30244587

RESUMO

Children with autism spectrum disorders appear to be at a higher risk of having obesity than their typically developing peers. Although it has been recommended that healthcare providers speak to children with autism spectrum disorders about the potential health risks of unhealthy weight, no previous research has explored how healthcare providers communicate with them about this topic. The purpose of this study was to explore children's perspectives and experiences of discussing weight-related topics in healthcare consultations. Eight children were interviewed, and an interpretive phenomenological analysis informed the research approach and analysis of the data. Results indicated that weight-related discussions with healthcare providers were often met with trepidation, anxiety, anger, and frustration. Children also expressed that they experienced weight stigma in clinical visits and everyday interactions. Weight stigma was often (unwittingly) projected by healthcare providers during appointments and had debilitating effects on children. Finally, higher weights emerged as a repetitive/restricted interest, and children reported body image challenges regarding their higher weights. Frameworks and tools that are specific to the needs and abilities of children with autism spectrum disorders are needed for healthcare providers to foster positive conversations about weight-related topics in an effort to promote lifelong wellness.


Assuntos
Atitude Frente a Saúde , Transtorno do Espectro Autista , Imagem Corporal , Comunicação em Saúde , Sobrepeso , Relações Profissional-Paciente , Preconceito de Peso , Adolescente , Criança , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Estigma Social
6.
Mol Autism ; 9: 59, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30498564

RESUMO

Background: Pioglitazone is a promising compound for treatment of core autism spectrum disorder (ASD) symptoms as it targets multiple relevant pathways, including immune system alterations. Objective: This pilot study aimed to elucidate the maximum tolerated dose, safety, preliminary evidence of efficacy, and appropriate outcome measures in autistic children ages 5-12 years old. Methods: We conducted a 16-week prospective cohort, single blind, single arm, 2-week placebo run-in, dose-finding study of pioglitazone. Twenty-five participants completed treatment. A modified dose finding method was used to determine safety and dose response among three dose levels: 0.25 mg/kg, 0.5 mg/kg, and 0.75 mg/kg once daily. Results: Maximum tolerated dose: there were no serious adverse events (SAEs) and as such the maximum tolerated dose within the range tested was 0.75 mg/Kg once daily.Safety: overall, pioglitazone was well tolerated. Two participants discontinued intervention due to perceived non-efficacy and one due to the inability to tolerate interim blood work. Three participants experienced mild neutropenia.Early evidence of efficacy: statistically significant improvement was observed in social withdrawal, repetitive behaviors, and externalizing behaviors as measured by the Aberrant Behavior Checklist (ABC), Child Yale-Brown Obsessive Compulsive Scale (CY-BOCS), and Repetitive Behavior Scale-Revised (RBS-R). Forty-six percent of those enrolled were deemed to be global responders. Conclusions and relevance: Pioglitazone is well-tolerated and shows a potential signal in measures of social withdrawal, repetitive, and externalizing behaviors. Randomized controlled trials using the confirmed dose are warranted. Trial registration: ClinicalTrials.gov, NCT01205282. Registration date: September 20, 2010.


Assuntos
Transtorno Autístico/tratamento farmacológico , Pioglitazona/administração & dosagem , Criança , Feminino , Humanos , Masculino , Projetos Piloto , Pioglitazona/efeitos adversos , Pioglitazona/farmacocinética , Pioglitazona/uso terapêutico
7.
Autism Res ; 11(11): 1500-1510, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30273978

RESUMO

Children with autism spectrum disorder (ASD) are at a higher risk of having obesity than their typically developing peers. Although it has been recommended that health care providers (HCPs) speak to caregivers and children about the risk of higher weights, no research has examined how HCPs communicate weight-related information. Furthermore, there is a dearth of evidence regarding how to approach and deliver optimal weight-related discussions among children with ASD and their caregivers. Given these knowledge gaps, 21 in-depth interviews were conducted with children with ASD, their caregivers, and HCPs. Using a qualitative analytic approach, data from interviews were analyzed thematically. Results suggest that HCPs at times projected weight stigma during clinical encounters, which did not motivate children and caregivers to work toward work loss or wellness. HCPs also described reticence in engaging families in weight-related conversations due to limited training, and lack of clinical tools to guide these conversations. All stakeholders identified a need to work together to establish a therapeutic partnership to discuss weight-related issues without blame or shame. The combination of strength-based communication approaches, establishing a strong therapeutic partnership, and development of clinical tools facilitating weight-related discussions for HCPs outlined in this article are potential vehicles to foster successful weight-related discussions while promoting lifelong wellness. Autism Research 2018, 11: 1500-1510. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Children with autism spectrum disorder (ASD) are at a higher risk of having obesity. Yet, it is unknown how healthcare providers (HCPs) should deliver weight-related information. Findings suggest children and caregivers experienced weight stigma and were uncomfortable discussing weight-related issues. HCPs identified that they did not have sufficient training, and did not feel confident identifying/addressing weight issues. Tools are needed to facilitate weight-related discussions among children, caregivers and HCPs.


Assuntos
Atitude do Pessoal de Saúde , Transtorno do Espectro Autista/complicações , Cuidadores/psicologia , Comunicação em Saúde/métodos , Obesidade Infantil/complicações , Encaminhamento e Consulta , Adolescente , Transtorno do Espectro Autista/psicologia , Criança , Feminino , Humanos , Entrevistas como Assunto , Masculino , Obesidade Infantil/psicologia , Obesidade Infantil/terapia
8.
J Am Acad Child Adolesc Psychiatry ; 56(10): 849-856.e6, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28942807

RESUMO

OBJECTIVE: A previous study reported on a 16-week placebo-controlled, randomized clinical trial (RCT) of metformin for weight stabilization in 61 children and adolescents 6 to 17 years old with autism spectrum disorder who were prescribed atypical antipsychotics. The present study describes the results of a 16-week open-label extension. METHOD: Fifty-two participants from the acute trial (85%) entered the extension; 22 had been on metformin during the initial RCT and 30 had been on placebo. Participants were re-titrated to 500 mg twice a day (6- to 9-year-olds) or 850 mg twice a day (10- to 17-year-olds) during the open-label extension. Primary outcome measure was change in body mass index (BMI) z-score after 16 weeks; secondary outcomes were change in additional body composition and metabolic parameters. RESULTS: After 16 weeks of open-label treatment, participants initially taking placebo during the RCT had lower BMI z-scores (mean 16-week change -0.10, p = .004). Statistically significant improvements also were noted in secondary body composition measures (weight z-score and BMI and weight percentile) but not in metabolic variables. Participants who initially had been taking metformin during the 16-week RCT maintained prior decreases in BMI z-scores but did not have additional weight loss. Three participants discontinued treatment because of an adverse event. No significant changes were noted on metabolic measures, although the decrease in hemoglobin A1c was large (∼1 mmol) and consistent across the acute and open-label phases. CONCLUSION: Metformin can be effective for decreasing weight gain associated with atypical antipsychotic use and maintaining prior improvement in children and adolescents with autism spectrum disorder. Clinical trial registration information-Treatment of Overweight Induced by Antipsychotic Medication in Young People With Autism Spectrum Disorders (ASD); http://clinicaltrials.gov/; NCT01825798.


Assuntos
Antipsicóticos/efeitos adversos , Transtorno do Espectro Autista/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Sobrepeso/tratamento farmacológico , Adolescente , Antipsicóticos/uso terapêutico , Criança , Feminino , Humanos , Masculino , Sobrepeso/induzido quimicamente , Resultado do Tratamento
9.
JAMA Psychiatry ; 73(9): 928-37, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27556593

RESUMO

IMPORTANCE: Atypical antipsychotic medications are indicated for the treatment of irritability and agitation symptoms in children with autism spectrum disorder (ASD). Unfortunately, these medications are associated with weight gain and metabolic complications that are especially troubling in children and with long-term use. OBJECTIVE: To evaluate the efficacy of metformin for weight gain associated with atypical antipsychotic medications in children and adolescents with ASD (defined in the protocol as DSM-IV diagnosis of autistic disorder, Asperger disorder, or pervasive developmental disorder not otherwise specified), aged 6 to 17 years. DESIGN, SETTING, AND PARTICIPANTS: A 16-week, double-blind, placebo-controlled, randomized clinical trial was conducted at 4 centers in Toronto, Ontario, Canada; Columbus, Ohio; Pittsburgh, Pennsylvania; and Nashville, Tennessee. In all, 209 potential participants were screened by telephone, 69 individuals provided consent, and 61 participants were randomized to receive metformin or placebo between April 26, 2013, and June 24, 2015. INTERVENTIONS: Metformin or matching placebo titrated up to 500 mg twice daily for children aged 6 to 9 years and 850 mg twice daily for those 10 to 17 years. MAIN OUTCOMES AND MEASURES: The primary outcome measure was change in body mass index (BMI) z score during 16 weeks of treatment. Secondary outcomes included changes in additional body composition and metabolic variables. Safety, tolerability, and efficacy analyses all used a modified intent-to-treat sample comprising all participants who received at least 1 dose of medication. RESULTS: Of the 61 randomized participants, 60 participants initiated treatment (45 [75%] male; mean [SD] age, 12.8 [2.7] years). Metformin reduced BMI z scores from baseline to week 16 significantly more than placebo (difference in 16-week change scores vs placebo, -0.10 [95% CI, -0.16 to -0.04]; P = .003). Statistically significant improvements were also noted in secondary body composition measures (raw BMI, -0.95 [95% CI, -1.46 to -0.45] and raw weight, -2.73 [95% CI, -4.04 to -1.43]) but not in metabolic variables. Overall, metformin was well tolerated. Five participants in the metformin group discontinued treatment owing to adverse events (agitation, 4; sedation, 1). Participants receiving metformin vs placebo experienced gastrointestinal adverse events during a significantly higher percentage of treatment days (25.1% vs 6.8%; P = .005). CONCLUSIONS AND RELEVANCE: Metformin may be effective in decreasing weight gain associated with atypical antipsychotic use and is well tolerated by children and adolescents with ASD. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01825798.


Assuntos
Antipsicóticos/efeitos adversos , Antipsicóticos/uso terapêutico , Transtorno do Espectro Autista/tratamento farmacológico , Metformina/uso terapêutico , Sobrepeso/induzido quimicamente , Sobrepeso/tratamento farmacológico , Adolescente , Índice de Massa Corporal , Criança , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Análise de Intenção de Tratamento , Masculino , Metformina/efeitos adversos , Aumento de Peso/efeitos dos fármacos
10.
Can J Psychiatry ; 53(6): 392-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18616860

RESUMO

OBJECTIVES: To explore the prevalence of mathematics disorder (MD) relative to reading disorders (RD) in school-age children with attention-deficit hyperactivity disorder (ADHD) and examine the effects of age, sex, cooccurring conduct disorder (CD), and ADHD subtype on this comorbidity. METHODS: Participants were school-age children (n = 476) with confirmed DSM-IV diagnosis of ADHD. The assessment included semistructured parent and teacher interviews and standardized measures of intelligence, academic attainment, and language abilities. Based on the presence or absence of concurrent learning disorders, we compared the emerging 4 groups: ADHD-only, ADHD + MD, ADHD + RD, and ADHD + MD + RD. RESULTS: Overall prevalence of comorbid ADHD + MD was 18.1%. Age, sex, ADHD subtypes, or comorbid CD did not affect the frequency of MD. Children with concurrent ADHD and either MD or RD attained lower IQ, language, and academic scores than those with ADHD alone. Children with ADHD + MD + RD were more seriously impaired and demonstrated distinct deficits in receptive and expressive language. CONCLUSION: MDs are relatively common in school-age children with ADHD and are frequently associated with RDs. Children with ADHD + MD + RD are more severely impaired. These deficits simply cannot be explained as consequences of ADHD and might have unique biological underpinnings, with implications for diagnostic classification and therapeutic interventions.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Deficiências da Aprendizagem/diagnóstico , Deficiências da Aprendizagem/epidemiologia , Matemática , Logro , Criança , Comorbidade , Transtorno da Conduta/diagnóstico , Transtorno da Conduta/epidemiologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Avaliação Educacional , Humanos , Prevalência
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