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2.
Mol Psychiatry ; 29(1): 186-196, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38102483

RESUMO

Autism spectrum disorder (ASD) comprises a large group of neurodevelopmental conditions featuring, over a wide range of severity and combinations, a core set of manifestations (restricted sociality, stereotyped behavior and language impairment) alongside various comorbidities. Common and rare variants in several hundreds of genes and regulatory regions have been implicated in the molecular pathogenesis of ASD along a range of causation evidence strength. Despite significant progress in elucidating the impact of few paradigmatic individual loci, such sheer complexity in the genetic architecture underlying ASD as a whole has hampered the identification of convergent actionable hubs hypothesized to relay between the vastness of risk alleles and the core phenotypes. In turn this has limited the development of strategies that can revert or ameliorate this condition, calling for a systems-level approach to probe the cross-talk of cooperating genes in terms of causal interaction networks in order to make convergences experimentally tractable and reveal their clinical actionability. As a first step in this direction, we have captured from the scientific literature information on the causal links between the genes whose variants have been associated with ASD and the whole human proteome. This information has been annotated in a computer readable format in the SIGNOR database and is made freely available in the resource website. To link this information to cell functions and phenotypes, we have developed graph algorithms that estimate the functional distance of any protein in the SIGNOR causal interactome to phenotypes and pathways. The main novelty of our approach resides in the possibility to explore the mechanistic links connecting the suggested gene-phenotype relations.


Assuntos
Transtorno do Espectro Autista , Predisposição Genética para Doença , Transtornos do Neurodesenvolvimento , Fenótipo , Humanos , Transtorno do Espectro Autista/genética , Predisposição Genética para Doença/genética , Transtornos do Neurodesenvolvimento/genética , Redes Reguladoras de Genes/genética , Transtorno Autístico/genética , Estudos de Associação Genética/métodos , Proteoma/genética
3.
Sci Adv ; 9(48): eadh2726, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38019906

RESUMO

Copy number variations at 7q11.23 cause neurodevelopmental disorders with shared and opposite manifestations. Deletion causes Williams-Beuren syndrome featuring hypersociability, while duplication causes 7q11.23 microduplication syndrome (7Dup), frequently exhibiting autism spectrum disorder (ASD). Converging evidence indicates GTF2I as key mediator of the cognitive-behavioral phenotypes, yet its role in cortical development and behavioral hallmarks remains largely unknown. We integrated proteomic and transcriptomic profiling of patient-derived cortical organoids, including longitudinally at single-cell resolution, to dissect 7q11.23 dosage-dependent and GTF2I-specific disease mechanisms. We observed dosage-dependent impaired dynamics of neural progenitor proliferation, transcriptional imbalances, and highly specific alterations in neuronal output, leading to precocious excitatory neuron production in 7Dup, which was rescued by restoring physiological GTF2I levels. Transgenic mice with Gtf2i duplication recapitulated progenitor proliferation and neuronal differentiation defects alongside ASD-like behaviors. Consistently, inhibition of lysine demethylase 1 (LSD1), a GTF2I effector, was sufficient to rescue ASD-like phenotypes in transgenic mice, establishing GTF2I-LSD1 axis as a molecular pathway amenable to therapeutic intervention in ASD.


Assuntos
Transtorno do Espectro Autista , Fatores de Transcrição TFIII , Fatores de Transcrição TFII , Camundongos , Animais , Humanos , Transtorno do Espectro Autista/genética , Variações do Número de Cópias de DNA , Proteômica , Comportamento Social , Fenótipo , Camundongos Transgênicos , Diferenciação Celular/genética , Histona Desmetilases/genética , Fatores de Transcrição TFIII/genética , Fatores de Transcrição TFII/genética
4.
Transl Psychiatry ; 12(1): 520, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36539399

RESUMO

Brain organoids are becoming increasingly relevant to dissect the molecular mechanisms underlying psychiatric and neurological conditions. The in vitro recapitulation of key features of human brain development affords the unique opportunity of investigating the developmental antecedents of neuropsychiatric conditions in the context of the actual patients' genetic backgrounds. Specifically, multiple strategies of brain organoid (BO) differentiation have enabled the investigation of human cerebral corticogenesis in vitro with increasing accuracy. However, the field lacks a systematic investigation of how closely the gene co-expression patterns seen in cultured BO from different protocols match those observed in fetal cortex, a paramount information for ensuring the sensitivity and accuracy of modeling disease trajectories. Here we benchmark BO against fetal corticogenesis by integrating transcriptomes from in-house differentiated cortical BO (CBO), other BO systems, human fetal brain samples processed in-house, and prenatal cortices from the BrainSpan Atlas. We identified co-expression patterns and prioritized hubs of human corticogenesis and CBO differentiation, highlighting both well-preserved and discordant trends across BO protocols. We evaluated the relevance of identified gene modules for neurodevelopmental disorders and psychiatric conditions finding significant enrichment of disease risk genes especially in modules related to neuronal maturation and synapsis development. The longitudinal transcriptomic analysis of CBO revealed a two-step differentiation composed of a fast-evolving phase, corresponding to the appearance of the main cell populations of the cortex, followed by a slow-evolving one characterized by milder transcriptional changes. Finally, we observed heterochronicity of differentiation across BO models compared to fetal cortex. Our approach provides a framework to directly compare the extent of in vivo/in vitro alignment of neurodevelopmentally relevant processes and their attending temporalities, structured as a resource to query for modeling human corticogenesis and the neuropsychiatric outcomes of its alterations.


Assuntos
Benchmarking , Córtex Cerebral , Humanos , Encéfalo , Neurogênese , Organoides
5.
Cell Rep ; 39(1): 110615, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35385734

RESUMO

Mutations in the chromodomain helicase DNA-binding 8 (CHD8) gene are a frequent cause of autism spectrum disorder (ASD). While its phenotypic spectrum often encompasses macrocephaly, implicating cortical abnormalities, how CHD8 haploinsufficiency affects neurodevelopmental is unclear. Here, employing human cerebral organoids, we find that CHD8 haploinsufficiency disrupted neurodevelopmental trajectories with an accelerated and delayed generation of, respectively, inhibitory and excitatory neurons that yields, at days 60 and 120, symmetrically opposite expansions in their proportions. This imbalance is consistent with an enlargement of cerebral organoids as an in vitro correlate of patients' macrocephaly. Through an isogenic design of patient-specific mutations and mosaic organoids, we define genotype-phenotype relationships and uncover their cell-autonomous nature. Our results define cell-type-specific CHD8-dependent molecular defects related to an abnormal program of proliferation and alternative splicing. By identifying cell-type-specific effects of CHD8 mutations, our study uncovers reproducible developmental alterations that may be employed for neurodevelopmental disease modeling.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Megalencefalia , Transtorno do Espectro Autista/genética , Transtorno Autístico/genética , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Haploinsuficiência/genética , Humanos , Megalencefalia/genética , Fatores de Transcrição/genética
6.
Science ; 375(6582): eabe8244, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35175820

RESUMO

Convergent evidence associates exposure to endocrine disrupting chemicals (EDCs) with major human diseases, even at regulation-compliant concentrations. This might be because humans are exposed to EDC mixtures, whereas chemical regulation is based on a risk assessment of individual compounds. Here, we developed a mixture-centered risk assessment strategy that integrates epidemiological and experimental evidence. We identified that exposure to an EDC mixture in early pregnancy is associated with language delay in offspring. At human-relevant concentrations, this mixture disrupted hormone-regulated and disease-relevant regulatory networks in human brain organoids and in the model organisms Xenopus leavis and Danio rerio, as well as behavioral responses. Reinterrogating epidemiological data, we found that up to 54% of the children had prenatal exposures above experimentally derived levels of concern, reaching, for the upper decile compared with the lowest decile of exposure, a 3.3 times higher risk of language delay.


Assuntos
Disruptores Endócrinos/toxicidade , Transtornos do Desenvolvimento da Linguagem/epidemiologia , Transtornos do Neurodesenvolvimento/epidemiologia , Efeitos Tardios da Exposição Pré-Natal , Transcriptoma/efeitos dos fármacos , Animais , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/genética , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Pré-Escolar , Estrogênios/metabolismo , Feminino , Fluorocarbonos/análise , Fluorocarbonos/toxicidade , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Ontologia Genética , Humanos , Locomoção/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Transtornos do Neurodesenvolvimento/genética , Organoides , Fenóis/análise , Fenóis/toxicidade , Ácidos Ftálicos/análise , Ácidos Ftálicos/toxicidade , Gravidez , Medição de Risco , Hormônios Tireóideos/metabolismo , Xenopus laevis , Peixe-Zebra
8.
Sci Rep ; 11(1): 18043, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508139

RESUMO

Interferons (IFNs) are key cytokines involved in alerting the immune system to viral infection. After IFN stimulation, cellular transcriptional profile critically changes, leading to the expression of several IFN stimulated genes (ISGs) that exert a wide variety of antiviral activities. Despite many ISGs have been already identified, a comprehensive network of coding and non-coding genes with a central role in IFN-response still needs to be elucidated. We performed a global RNA-Seq transcriptome profile of the HCV permissive human hepatoma cell line Huh7.5 and its parental cell line Huh7, upon IFN treatment, to define a network of genes whose coordinated modulation plays a central role in IFN-response. Our study adds molecular actors, coding and non-coding genes, to the complex molecular network underlying IFN-response and shows how systems biology approaches, such as correlation networks, network's topology and gene ontology analyses can be leveraged to this aim.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fatores Reguladores de Interferon/genética , Interferons/metabolismo , Biologia de Sistemas/métodos , Transcriptoma , Sítios de Ligação , Linhagem Celular Tumoral , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes , Humanos , Fatores Reguladores de Interferon/metabolismo , Interferons/farmacologia , Neoplasias Hepáticas , Motivos de Nucleotídeos , Ligação Proteica
9.
Hum Mol Genet ; 30(13): 1175-1187, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33601422

RESUMO

Synaptic dysfunction and cognitive decline in Huntington's disease (HD) involve hyperactive A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10). To identify the molecular mechanisms through which ADAM10 is associated with synaptic dysfunction in HD, we performed an immunoaffinity purification-mass spectrometry (IP-MS) study of endogenous ADAM10 in the brains of wild-type and HD mice. We found that proteins implicated in synapse organization, synaptic plasticity, and vesicle and organelles trafficking interact with ADAM10, suggesting that it may act as hub protein at the excitatory synapse. Importantly, the ADAM10 interactome is enriched in presynaptic proteins and ADAM10 co-immunoprecipitates with piccolo (PCLO), a key player in the recycling and maintenance of synaptic vesicles. In contrast, reduced ADAM10/PCLO immunoprecipitation occurs in the HD brain, with decreased density of synaptic vesicles in the reserve and docked pools at the HD presynaptic terminal. Conditional heterozygous deletion of ADAM10 in the forebrain of HD mice reduces active ADAM10 to wild-type level and normalizes ADAM10/PCLO complex formation and synaptic vesicle density and distribution. The results indicate that presynaptic ADAM10 and PCLO are a relevant component of HD pathogenesis.


Assuntos
Proteína ADAM10/metabolismo , Proteínas do Citoesqueleto/metabolismo , Doença de Huntington/metabolismo , Neuropeptídeos/metabolismo , Vesículas Sinápticas/metabolismo , Proteína ADAM10/genética , Animais , Western Blotting , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Humanos , Doença de Huntington/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Terminações Pré-Sinápticas/metabolismo , Ligação Proteica , Mapas de Interação de Proteínas/genética , Proteômica/métodos , Vesículas Sinápticas/ultraestrutura , Sinaptossomos/metabolismo , Espectrometria de Massas em Tandem/métodos
10.
Mol Autism ; 11(1): 69, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912338

RESUMO

The complex pathophysiology of autism spectrum disorder encompasses interactions between genetic and environmental factors. On the one hand, hundreds of genes, converging at the functional level on selective biological domains such as epigenetic regulation and synaptic function, have been identified to be either causative or risk factors of autism. On the other hand, exposure to chemicals that are widespread in the environment, such as endocrine disruptors, has been associated with adverse effects on human health, including neurodevelopmental disorders. Interestingly, experimental results suggest an overlap in the regulatory pathways perturbed by genetic mutations and environmental factors, depicting convergences and complex interplays between genetic susceptibility and toxic insults. The pervasive nature of chemical exposure poses pivotal challenges for neurotoxicological studies, regulatory agencies, and policy makers. This highlights an emerging need of developing new integrative models, including biomonitoring, epidemiology, experimental, and computational tools, able to capture real-life scenarios encompassing the interaction between chronic exposure to mixture of substances and individuals' genetic backgrounds. In this review, we address the intertwined roles of genetic lesions and environmental insults. Specifically, we outline the transformative potential of stem cell models, coupled with omics analytical approaches at increasingly single cell resolution, as converging tools to experimentally dissect the pathogenic mechanisms underlying neurodevelopmental disorders, as well as to improve developmental neurotoxicology risk assessment.


Assuntos
Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/fisiopatologia , Interação Gene-Ambiente , Transtorno do Espectro Autista/epidemiologia , Predisposição Genética para Doença , Humanos , Fatores de Risco , Revisões Sistemáticas como Assunto
11.
Stem Cell Reports ; 13(5): 847-861, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31607568

RESUMO

The regulation of the proliferation and polarity of neural progenitors is crucial for the development of the brain cortex. Animal studies have implicated glycogen synthase kinase 3 (GSK3) as a pivotal regulator of both proliferation and polarity, yet the functional relevance of its signaling for the unique features of human corticogenesis remains to be elucidated. We harnessed human cortical brain organoids to probe the longitudinal impact of GSK3 inhibition through multiple developmental stages. Chronic GSK3 inhibition increased the proliferation of neural progenitors and caused massive derangement of cortical tissue architecture. Single-cell transcriptome profiling revealed a direct impact on early neurogenesis and uncovered a selective role of GSK3 in the regulation of glutamatergic lineages and outer radial glia output. Our dissection of the GSK3-dependent transcriptional network in human corticogenesis underscores the robustness of the programs determining neuronal identity independent of tissue architecture.


Assuntos
Córtex Cerebral/citologia , Quinase 3 da Glicogênio Sintase/metabolismo , Neurogênese , Neurônios/citologia , Organoides/citologia , Linhagem Celular , Proliferação de Células , Córtex Cerebral/metabolismo , Deleção de Genes , Quinase 3 da Glicogênio Sintase/genética , Humanos , Neurônios/metabolismo , Organoides/metabolismo , Transcriptoma
12.
Dev Biol ; 455(1): 100-111, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31283922

RESUMO

During development, ribosome biogenesis and translation reach peak activities, due to impetuous cell proliferation. Current models predict that protein synthesis elevation is controlled by transcription factors and signalling pathways. Developmental models addressing translation factors overexpression effects are lacking. Eukaryotic Initiation Factor 6 (eIF6) is necessary for ribosome biogenesis and efficient translation. eIF6 is a single gene, conserved from yeasts to mammals, suggesting a tight regulation need. We generated a Drosophila melanogaster model of eIF6 upregulation, leading to a boost in general translation and the shut-down of the ecdysone biosynthetic pathway. Indeed, translation modulation in S2 cells showed that translational rate and ecdysone biosynthesis are inversely correlated. In vivo, eIF6-driven alterations delayed Programmed Cell Death (PCD), resulting in aberrant phenotypes, partially rescued by ecdysone administration. Our data show that eIF6 triggers a translation program with far-reaching effects on metabolism and development, stressing the driving and central role of translation.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Ecdisona/biossíntese , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Iniciação de Peptídeos/genética , Biossíntese de Proteínas/genética , Animais , Animais Geneticamente Modificados , Apoptose/genética , Linhagem Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Discos Imaginais/crescimento & desenvolvimento , Discos Imaginais/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
13.
PLoS Genet ; 13(1): e1006552, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28056084

RESUMO

Ribosomopathies are a family of inherited disorders caused by mutations in genes necessary for ribosomal function. Shwachman-Diamond Bodian Syndrome (SDS) is an autosomal recessive disease caused, in most patients, by mutations of the SBDS gene. SBDS is a protein required for the maturation of 60S ribosomes. SDS patients present exocrine pancreatic insufficiency, neutropenia, chronic infections, and skeletal abnormalities. Later in life, patients are prone to myelodisplastic syndrome and acute myeloid leukemia (AML). It is unknown why patients develop AML and which cellular alterations are directly due to the loss of the SBDS protein. Here we derived mouse embryonic fibroblast lines from an SbdsR126T/R126T mouse model. After their immortalization, we reconstituted them by adding wild type Sbds. We then performed a comprehensive analysis of cellular functions including colony formation, translational and transcriptional RNA-seq, stress and drug sensitivity. We show that: 1. Mutant Sbds causes a reduction in cellular clonogenic capability and oncogene-induced transformation. 2. Mutant Sbds causes a marked increase in immature 60S subunits, limited impact on mRNA specific initiation of translation, but reduced global protein synthesis capability. 3. Chronic loss of SBDS activity leads to a rewiring of gene expression with reduced ribosomal capability, but increased lysosomal and catabolic activity. 4. Consistently with the gene signature, we found that SBDS loss causes a reduction in ATP and lactate levels, and increased susceptibility to DNA damage. Combining our data, we conclude that a cell-specific fragile phenotype occurs when SBDS protein drops below a threshold level, and propose a new interpretation of the disease.


Assuntos
Homeostase , Fenótipo , Proteínas/genética , Subunidades Ribossômicas Maiores de Eucariotos/genética , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Transformação Celular Neoplásica , Dano ao DNA , Fibroblastos/metabolismo , Ácido Láctico/metabolismo , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo
14.
Hepatology ; 63(2): 418-27, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26517016

RESUMO

UNLABELLED: Chronic hepatitis C virus (HCV) infection may progress to cirrhosis and hepatocellular carcinoma (HCC). Recently, two genetic variants, DEPDC5 rs1012068 and MICA rs2596542, were associated with the onset of HCC in Asian subjects with chronic HCV infection. The aim of the present study was to analyze whether DEPDC5 and MICA genetic variants were associated with liver disease progression in European subjects with chronic HCV infection. In a Northern Italian discovery cohort (n = 477), neither DEPDC5 rs1012068 nor MICA rs2596542 were associated with HCC (n = 150). However, DEPDC5 rs1012068 was independently associated with cirrhosis (n = 300; P = 0.049). The association of rs1012068 with moderate to severe fibrosis was confirmed in an independent cross-sectional German cohort (n = 415; P = 0.006). Furthermore, DEPDC5 rs1012068 predicted faster fibrosis progression in a prospective cohort (n = 247; P = 0.027). Next, we examined the distribution of nonsynonymous DEPDC5 variants in the overall cross-sectional cohort (n = 912). The presence of at least one variant increased the risk of moderate/severe fibrosis by 54% (P = 0.040). To understand the molecular mechanism underlying the genetic association of DEPDC5 variants with fibrosis progression, we performed in vitro studies on immortalized hepatic stellate cells (LX-2). In these cells, down-regulation of DEPDC5 resulted in increased expression of ß-catenin and production of its target matrix metallopeptidase 2 (MMP2), a secreted enzyme involved in fibrosis progression. CONCLUSION: DEPDC5 variants increase fibrosis progression in European subjects with chronic HCV infection. Our findings suggest that DEPDC5 down-regulation may contribute to HCV-related fibrosis by increasing MMP2 synthesis through the ß-catenin pathway.


Assuntos
Carcinoma Hepatocelular/etiologia , Progressão da Doença , Hepatite C Crônica/complicações , Hepatite C Crônica/genética , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , Proteínas Repressoras/genética , Estudos Transversais , Feminino , Proteínas Ativadoras de GTPase , Variação Genética , Alemanha , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Suíça , População Branca
15.
PLoS One ; 10(9): e0138546, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26405760

RESUMO

Hepatitis C virus (HCV) variants characterized by genomic deletions in the structural protein region have been sporadically detected in liver and serum of hepatitis C patients. These defective genomes are capable of autonomous RNA replication and are packaged into infectious viral particles in cells co-infected with the wild-type virus. The prevalence of such forms in the chronically HCV-infected population and the impact on the severity of liver disease or treatment outcome are currently unknown. In order to determine the prevalence of HCV defective variants and to study their association with clinical characteristics, a screening campaign was performed on pre-therapy serum samples from a well-characterized cohort of previously untreated genotype 1 HCV-infected patients who received treatment with PEG-IFNα and RBV. 132 subjects were successfully analyzed for the presence of defective species exploiting a long-distance nested PCR assay. HCV forms with deletions predominantly affecting E1, E2 and p7 proteins were found in a surprising high fraction of the subjects (25/132, 19%). Their presence was associated with patient older age, higher viral load and increased necroinflammatory activity in the liver. While the presence of circulating HCV carrying deletions in the E1-p7 region did not appear to significantly influence sustained virological response rates to PEG-IFNα/RBV, our study indicates that the presence of these subgenomic HCV mutants could be associated with virological relapse in patients who did not have detectable viremia at the end of the treatment.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/virologia , Fígado/patologia , Deleção de Sequência , Proteínas Virais/genética , Adulto , Fatores Etários , Idoso , Feminino , Genótipo , Hepatite C Crônica/sangue , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/patologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Fígado/virologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Prevalência , Proteínas Recombinantes/uso terapêutico , Recidiva , Ribavirina/uso terapêutico , Proteínas do Envelope Viral/genética , Carga Viral
16.
Neurobiol Aging ; 36(1): 492-504, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25085783

RESUMO

Amyotrophic lateral sclerosis (ALS) is a disease of variable severity in terms of speed of progression of the disease course. We found a similar variability in disease onset and progression of 2 familial ALS mouse strains, despite the fact that they carry the same transgene copy number and express the same amount of mutant SOD1G93A messenger RNA and protein in the central nervous system. Comparative analysis of 2 SOD1G93A mouse strains highlights differences associated with the disease severity that are unrelated to the degree of motor neuron loss but that appear to promote early dysfunction of these cells linked to protein aggregation. Features of fast progressing phenotype are (1) abundant protein aggregates containing mutant SOD1 and multiple chaperones; (2) low basal expression of the chaperone alpha-B-crystallin (CRYAB) and ß5 subunits of proteasome; and (3) downregulation of proteasome subunit expression at disease onset. In contrast, high levels of functional chaperones such as cyclophillin-A and CRYAB, combined with delayed alteration of expression of proteasome subunits and the sequestration of TDP43 into aggregates, are features associated with a more slowly progressing pathology. These data support the hypothesis that impairment of protein homeostasis caused by low-soluble chaperone levels, together with malfunction of the proteasome degradation machinery, contributes to accelerate motor neuron dysfunction and progression of disease symptoms. Therefore, modulating the activity of these systems could represent a rational therapeutic strategy for slowing down disease progression in SOD1-related ALS.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Fenótipo , Superóxido Dismutase/metabolismo , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/terapia , Animais , Sistema Nervoso Central/metabolismo , Ciclofilina A/metabolismo , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Camundongos Transgênicos , Chaperonas Moleculares , Terapia de Alvo Molecular , Neurônios Motores/patologia , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Índice de Gravidade de Doença , Superóxido Dismutase/genética
17.
PLoS One ; 9(8): e106022, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25171251

RESUMO

BACKGROUND AND AIMS: The PNPLA3 I148M sequence variant favors hepatic lipid accumulation and confers susceptibility to hepatic fibrosis and hepatocellular carcinoma. The aim of this study was to estimate the effect size of homozygosity for the PNPLA3 I148M variant (148M/M) on the fibrosis progression rate (FPR) and the interaction with age at infection in chronic hepatitis C (CHC). METHODS: FPR was estimated in a prospective cohort of 247 CHC patients without alcohol intake and diabetes, with careful estimation of age at infection and determination of fibrosis stage by Ishak score. RESULTS: Older age at infection was the strongest determinant of FPR (p<0.0001). PNPLA3 148M/M was associated with faster FPR in individuals infected at older age (above the median, 21 years; -0.64±0.2, n = 8 vs. -0.95±0.3, n = 166 log10 FPR respectively; p = 0.001; confirmed for lower age thresholds, p<0.05), but not in those infected at younger age (p = ns). The negative impact of PNPLA3 148M/M on fibrosis progression was more marked in subjects at risk of altered hepatic lipid metabolism (those with grade 2-3 steatosis, genotype 3, and overweight; p<0.05). At multivariate analysis, PNPLA3 148M/M was associated with FPR (incremental effect 0.08±0.03 log10 fibrosis unit per year; p = 0.022), independently of several confounders, and there was a significant interaction between 148M/M and older age at infection (p = 0.025). The association between 148M/M and FPR remained significant even after adjustment for steatosis severity (p = 0.032). CONCLUSIONS: We observed an interaction between homozygosity for the PNPLA3 I148M variant and age at infection in determining fibrosis progression in CHC patients.


Assuntos
Hepatite C Crônica/genética , Lipase/genética , Cirrose Hepática/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Adolescente , Adulto , Fatores Etários , Idoso , Progressão da Doença , Fígado Gorduroso/complicações , Fígado Gorduroso/genética , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Hepatite C Crônica/complicações , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Adulto Jovem
18.
Front Immunol ; 5: 128, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24734033

RESUMO

Primary biliary cirrhosis (PBC) is an uncommon autoimmune disease with a homogeneous clinical phenotype that reflects incomplete disease concordance in monozygotic (MZ) twins. We have taken advantage of a unique collection consisting of genomic DNA and mRNA from peripheral blood cells of female MZ twins (n = 3 sets) and sisters of similar age (n = 8 pairs) discordant for disease. We performed a genome-wide study to investigate differences in (i) DNA methylation (using a custom tiled four-plex array containing tiled 50-mers 19,084 randomly chosen methylation sites), (ii) copy number variation (CNV) (with a chip including markers derived from the 1000 Genomes Project, all three HapMap phases, and recently published studies), and/or (iii) gene expression (by whole-genome expression arrays). Based on the results obtained from these three approaches we utilized quantitative PCR to compare the expression of candidate genes. Importantly, our data support consistent differences in discordant twins and siblings for the (i) methylation profiles of 60 gene regions, (ii) CNV of 10 genes, and (iii) the expression of 2 interferon-dependent genes. Quantitative PCR analysis showed that 17 of these genes are differentially expressed in discordant sibling pairs. In conclusion, we report that MZ twins and sisters discordant for PBC manifest particular epigenetic differences and highlight the value of the epigenetic study of twins.

19.
Int J Mol Sci ; 15(5): 7213-24, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24776764

RESUMO

The interleukin 28B (IL28B) rs12979860 polymorphism is associated with treatment outcome in hepatitis C virus (HCV) genotype 1 and 4 patients. Its association with the histological features of chronic hepatitis C and disease severity needs further clarifications. To assess the correlation between IL28B genotype, HCV genotype and liver biopsy findings in untreated patients. MATERIALS AND METHODS: Pre-treatment liver biopsies from 335 HCV Caucasian patients (59% males, age 50 years) enrolled in the MIST study were staged for fibrosis and inflammation according to the METAVIR and the Ishak scoring systems; steatosis was dichotomized as <5% or ≥5%. IL28B was typed by Taqman Single Nucleotide Polymorphism (SNP) genotyping assay. HCV genotype was 1 in 151 (45%), 2 in 99 (30%), 3 in 50 (15%) and 4 in 35 (10%) patients. IL28B genotype was CC in 117 (34%), CT in 166 (49%) and TT in 52 (15%). At univariate analysis, the IL28B CC genotype was associated with severe portal inflammation in HCV-1 patients (CC vs. CT/TT: 86% vs. 63%, p = 0.005), severe lobular inflammation in HCV-2 patients (CC vs. CT/TT: 44% vs. 23%, p = 0.03), and less fatty infiltration in HCV-1 patients (CC vs. CT/TT: 72% vs. 51%, p = 0.02). Despite the lack of any association between IL28B and fibrosis stage, in HCV-3 patients IL28B CC correlated with METAVIR F3-F4 (CC vs. CT/TT: 74% vs. 26%, p = 0.05). At multivariate analysis, the genotype CC remained associated with severe portal inflammation in HCV-1, only (Odds Ratio (OR): 95% Confidence Interval (CI): 3.24 (1.23-8.51)). IL28B genotype is associated with the histological features of chronic hepatitis C in a HCV genotype dependent manner, with CC genotype being independently associated with severe portal inflammation.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/genética , Hepatite C Crônica/patologia , Interleucinas/genética , Fígado/patologia , Fígado/virologia , Adulto , Idoso , Estudos de Coortes , Fígado Gorduroso/complicações , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Humanos , Inflamação/complicações , Interferons , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Adulto Jovem
20.
Antivir Ther ; 19(8): 747-53, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24523350

RESUMO

BACKGROUND: In patients with chronic HCV infection, an association between IL28B genotype and insulin-resistance (IR), known predictors of sustained virological response (SVR) to pegylated interferon (PEG-IFN) and ribavirin (RBV) therapy, has been reported. The aim of this study was to investigate the association of IR and IL28B genotype in two cohorts of well-characterized HCV patients. METHODS: A total of 480 non-diabetic HCV patients were analysed: 391 patients who received PEG-IFN/RBV in the MIST study and 89 previously reported patients followed at a metabolic liver diseases centre (Division of Internal Medicine, Fondazione IRCCS Ospedale Maggiore Policlinico, Milan, Italy). All were tested for IL28B rs12979860 single nucleotide polymorphism by real-time PCR and had IR measured by HOMA-IR. Staging of liver disease through liver biopsy was available for all patients. RESULTS: Overall, 164 patients (34%) were IL28B CC. Mean HOMA-IR values (±sd) did not differ according to IL28B genotype, being respectively 1.14 ±0.79 in CC versus 1.14 ±0.78 in CT/TT (P=1.0) in the first, and 2.4 ±1.0 versus 2.5 ±1.0 (P=0.7) in the second cohort. HOMA-IR>2 was not associated with IL28B genotype: 16/132 (12%) CC versus 31/259 (12%) CT/TT (P=1.0) in the first cohort and 16/32 (50%) versus 37/57 (65%; P=0.18) in the second. This held true also when using different HOMA cutoffs (>2.5, >3.0, >3.5 and >4.0). In the MIST cohort, HOMA-IR>2 did not influence treatment outcome, SVR rates being 28/47 (60%) in HOMA-IR>2 versus 214/344 (62%) in HOMA-IR≤2 (P=0.8). IL28B genotype was a strong predictor of SVR: 84% (111/132) in CC versus 51% (131/259) in CT/TT patients (P<0.0001). CONCLUSIONS: In two cohorts of non-diabetic HCV patients where IL28B genotype predicted treatment outcome, we found no association between IL28B genotype and HOMA-IR.


Assuntos
Genótipo , Hepatite C Crônica/genética , Hepatite C Crônica/metabolismo , Resistência à Insulina , Interleucinas/genética , Adulto , Idoso , Alelos , Antivirais/uso terapêutico , Estudos de Coortes , Feminino , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferons , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
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