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1.
J Neuroinflammation ; 19(1): 193, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35897073

RESUMO

BACKGROUND: Herbicides are environmental contaminants that have gained much attention due to the potential hazards they pose to human health. Glyphosate, the active ingredient in many commercial herbicides, is the most heavily applied herbicide worldwide. The recent rise in glyphosate application to corn and soy crops correlates positively with increased death rates due to Alzheimer's disease and other neurodegenerative disorders. Glyphosate has been shown to cross the blood-brain barrier in in vitro models, but has yet to be verified in vivo. Additionally, reports have shown that glyphosate exposure increases pro-inflammatory cytokines in blood plasma, particularly TNFα. METHODS: Here, we examined whether glyphosate infiltrates the brain and elevates TNFα levels in 4-month-old C57BL/6J mice. Mice received either 125, 250, or 500 mg/kg/day of glyphosate, or a vehicle via oral gavage for 14 days. Urine, plasma, and brain samples were collected on the final day of dosing for analysis via UPLC-MS and ELISAs. Primary cortical neurons were derived from amyloidogenic APP/PS1 pups to evaluate in vitro changes in Aß40-42 burden and cytotoxicity. RNA sequencing was performed on C57BL/6J brain samples to determine changes in the transcriptome. RESULTS: Our analysis revealed that glyphosate infiltrated the brain in a dose-dependent manner and upregulated TNFα in both plasma and brain tissue post-exposure. Notably, glyphosate measures correlated positively with TNFα levels. Glyphosate exposure in APP/PS1 primary cortical neurons increases levels of soluble Aß40-42 and cytotoxicity. RNAseq revealed over 200 differentially expressed genes in a dose-dependent manner and cell-type-specific deconvolution analysis showed enrichment of key biological processes in oligodendrocytes including myelination, axon ensheathment, glial cell development, and oligodendrocyte development. CONCLUSIONS: Collectively, these results show for the first time that glyphosate infiltrates the brain, elevates both the expression of TNFα and soluble Aß, and disrupts the transcriptome in a dose-dependent manner, suggesting that exposure to this herbicide may have detrimental outcomes regarding the health of the general population.


Assuntos
Doença de Alzheimer , Glicina , Herbicidas , Fator de Necrose Tumoral alfa , Animais , Encéfalo , Cromatografia Líquida , Citocinas/genética , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Espectrometria de Massas em Tandem , Glifosato
2.
Acta Neuropathol ; 142(2): 279-294, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33978814

RESUMO

Evidence indicates that tau hyper-phosphorylation and subsequent neurofibrillary tangle formation contribute to the extensive neuronal death in Alzheimer's disease (AD) and related tauopathies. Recent work has identified that increased tau acetylation can promote tau phosphorylation. Tau acetylation occurs at lysine 280 resulting from increased expression of the lysine acetyltransferase p300. The exact upstream mechanisms mediating p300 expression remain elusive. Additional work highlights the role of the epigenome in tau pathogenesis, suggesting that dysregulation of epigenetic proteins may contribute to acetylation and hyper-phosphorylation of tau. Here, we identify and focus on the histone-binding subunit of the Nucleosome Remodeling and Deacetylase (NuRD) complex: Retinoblastoma-Binding Protein 7 (Rbbp7). Rbbp7 chaperones chromatin remodeling proteins to their nuclear histone substrates, including histone acetylases and deacetylases. Notably, Rbbp7 binds to p300, suggesting that it may play a role in modulating tau acetylation. We interrogated Rbbp7 in post-mortem brain tissue, cell lines and mouse models of AD. We found reduced Rbbp7 mRNA expression in AD cases, a significant negative correlation with CERAD (neuritic plaque density) and Braak Staging (pathogenic tau inclusions) and a significant positive correlation with post-mortem brain weight. We also found a neuron-specific downregulation of Rbbp7 mRNA in AD patients. Rbbp7 protein levels were significantly decreased in 3xTg-AD and PS19 mice compared to NonTg, but no decreases were found in APP/PS1 mice that lack tau pathology. In vitro, Rbbp7 overexpression rescued TauP301L-induced cytotoxicity in immortalized hippocampal cells and primary cortical neurons. In vivo, hippocampal Rbbp7 overexpression rescued neuronal death in the CA1 of PS19 mice. Mechanistically, we found that increased Rbbp7 reduced p300 levels, tau acetylation at lysine 280 and tau phosphorylation at AT8 and AT100 sites. Collectively, these data identify a novel role of Rbbp7, protecting against tau-related pathologies, and highlight its potential as a therapeutic target in AD and related tauopathies.


Assuntos
Acetilação , Neurônios/patologia , Proteína 7 de Ligação ao Retinoblastoma/metabolismo , Tauopatias/patologia , Proteínas tau/metabolismo , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Camundongos , Neurônios/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Proteína 7 de Ligação ao Retinoblastoma/genética
3.
Hippocampus ; 31(5): 469-480, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33586848

RESUMO

While total white matter hyperintensity (WMH) volume on magnetic resonance imaging (MRI) has been associated with hippocampal atrophy, less is known about how the regional distribution of WMH volume may differentially affect the hippocampus in healthy aging. Additionally, apolipoprotein E (APOE) ε4 carriers may be at an increased risk for greater WMH volumes and hippocampal atrophy in aging. The present study sought to investigate whether regional WMH volume mediates the relationship between age and hippocampal volume and if this association is moderated by APOE ε4 status in a group of 190 cognitively healthy adults (APOE ε4 status [carrier/non-carrier] = 59/131), ages 50-89. Analyses revealed that temporal lobe WMH volume significantly mediated the relationship between age and average bilateral hippocampal volume, and this effect was moderated by APOE ε4 status (-0.020 (SE = 0.009), 95% CI, [-0.039, -0.003]). APOE ε4 carriers, but not non-carriers, showed negative indirect effects of age on hippocampal volume through temporal lobe WMH volume (APOE ε4 carriers: -0.016 (SE = 0.007), 95% CI, [-0.030, -0.003]; APOE ε4 non-carriers: .005 (SE = 0.006), 95% CI, [-0.006, 0.017]). These findings remained significant after additionally adjusting for sex, years of education, hypertension status and duration, cholesterol status, diabetes status, Body Mass Index, history of smoking, and the Wechsler Adult Intelligence Scale-IV Full Scale IQ. There were no significant moderated mediation effects for frontal, parietal, and occipital lobe WMH volumes, with or without covariates. Our findings indicate that in cognitively healthy older adults, elevated WMH volume regionally localized to the temporal lobes in APOE ε4 carriers is associated with reduced hippocampal volume, suggesting greater vulnerability to brain aging and the risk for Alzheimer's disease.


Assuntos
Doença de Alzheimer , Substância Branca , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
4.
Biol Open ; 10(1)2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-32878879

RESUMO

The organic anion transporter Adenosine triphosphate binding cassette subfamily C member 1 (ABCC1), also known as MRP1, has been demonstrated in murine models of Alzheimer's disease (AD) to export amyloid beta (Abeta) from the endothelial cells of the blood-brain barrier to the periphery, and that pharmaceutical activation of ABCC1 can reduce amyloid plaque deposition in the brain. Here, we show that ABCC1 is not only capable of exporting Abeta from the cytoplasm of human cells, but also that its overexpression significantly reduces Abeta production and increases the ratio of alpha- versus beta-secretase mediated cleavage of the amyloid precursor protein (APP), likely via indirect modulation of alpha-, beta- and gamma-secretase activity.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Expressão Gênica , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Linhagem Celular , Ativação Enzimática , Perfilação da Expressão Gênica , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteólise , Transcriptoma
5.
Neurol Genet ; 6(4): e468, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32754643

RESUMO

OBJECTIVE: Description of a new variant of the glutamine-fructose-6-phosphate transaminase 1 (GFPT1) gene causing congenital myasthenic syndrome (CMS) in 3 children from 2 unrelated families. METHODS: Muscle biopsies, EMG, and whole-exome sequencing were performed. RESULTS: All 3 patients presented with congenital hypotonia, muscle weakness, respiratory insufficiency, head lag, areflexia, and gastrointestinal dysfunction. Genetic analysis identified a homozygous frameshift insertion in the GFPT1 gene (NM_001244710.1: c.686dupC; p.Arg230Ter) that was shared by all 3 patients. In one of the patients, inheritance of the variant was through uniparental disomy (UPD) with maternal origin. Repetitive nerve stimulation and single-fiber EMG was consistent with the clinical diagnosis of CMS with a postjunctional defect. Ultrastructural evaluation of the muscle biopsy from one of the patients showed extremely attenuated postsynaptic folds at neuromuscular junctions and extensive autophagic vacuolar pathology. CONCLUSIONS: These results expand on the spectrum of known loss-of-function GFPT1 mutations in CMS12 and in one family demonstrate a novel mode of inheritance due to UPD.

6.
Genes (Basel) ; 11(6)2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486318

RESUMO

Canine idiopathic pulmonary fibrosis (CIPF) is a chronic fibrotic lung disease that is observed at a higher frequency in the West Highland White Terrier dog breed (WHWT) and may have molecular pathological overlap with human lung fibrotic disease. We conducted a genome-wide association study (GWAS) in the WHWT using whole genome sequencing (WGS) to discover genetic variants associated with CIPF. Saliva-derived DNA samples were sequenced using the Riptide DNA library prep kit. After quality controls, 28 affected, 44 unaffected, and 1,843,695 informative single nucleotide polymorphisms (SNPs) were included in the GWAS. Data were analyzed both at the single SNP and gene levels using the GEMMA and GATES methods, respectively. We detected significant signals at the gene level in both the cleavage and polyadenylation specific factor 7 (CPSF7) and succinate dehydrogenase complex assembly factor 2 (SDHAF2) genes (adjusted p = 0.016 and 0.024, respectively), two overlapping genes located on chromosome 18. The top SNP for both genes was rs22669389; however, it did not reach genome-wide significance in the GWAS (adjusted p = 0.078). Our studies provide, for the first time, candidate loci for CIPF in the WHWT. CPSF7 was recently associated with lung adenocarcinoma, further highlighting the potential relevance of our results because IPF and lung cancer share several pathological mechanisms.


Assuntos
Doenças do Cão/genética , Estudos de Associação Genética , Fibrose Pulmonar Idiopática/genética , Proteínas com Motivo de Reconhecimento de RNA/genética , Animais , Doenças do Cão/patologia , Cães , Predisposição Genética para Doença , Humanos , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/veterinária , Proteínas Mitocondriais/genética , Poliadenilação/genética , Polimorfismo de Nucleotídeo Único/genética
7.
Brain Behav Immun Health ; 5: 100084, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-34589859

RESUMO

The inflammatory response is an immune defense engaged immediately after injury or infection. Chronic inflammation can be deleterious for various health outcomes and is characterized by high levels of pro-inflammatory markers such as C-reactive protein (CRP), interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-α). A large body of research demonstrates these inflammatory markers are responsive to stress and quality of social relationships throughout the lifespan. For example, the quality of the early parental bond predicts various health outcomes and may be driven by changes in immune function. Epigenetic processes, such as DNA methylation, may be one mechanism by which early social experiences shape immune functioning. The present study used a monozygotic twin difference design to assess if mother-reported emotional availability at 1 year and 2.5 years predicted immune gene methylation at 8 years of age. Further, we assessed if inflammation gene methylation was related to general health problems (e.g. infections, allergies, etc.). We found that mother-reported emotional availability at 1 year, but not 2.5 years, was related to methylation of various immune genes in monozygotic twins. Furthermore, twin pairs discordant in health problems have more difference in immune gene methylation compared to twin pairs concordant for health problems, suggesting that methylation of immune genes may have functional consequences for general health. These results suggest that the emotional component of attachment quality during infancy contributes to immune epigenetic profiles in childhood, which may influence general health.

8.
Behav Genet ; 49(4): 399-414, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30949922

RESUMO

Recent studies of autism spectrum disorder (ASD) and childhood apraxia of speech (CAS) have resulted in conflicting conclusions regarding the comorbidity of these disorders on phenotypic grounds. In a nuclear family with two dually affected and one unaffected offspring, whole-exome sequences were evaluated for single nucleotide and indel variants and CNVs. The affected siblings but not the unaffected sibling share a rare deleterious compound heterozygous mutation in WWOX, implicated both in ASD and motor control. In addition, one of the affected children carries a rare deleterious de novo mutation in the ASD candidate gene RIMS1. The two affected children but not their unaffected sibling inherited deleterious variants with relevance for ASD and/or CAS. WWOX, RIMS1, and several of the genes harboring the inherited variants are expressed in the brain during prenatal and early postnatal development. Results suggest compound heterozygosity as a cause of ASD and CAS, pleiotropic gene effects, and potentially additional, complex genetic effects.


Assuntos
Transtorno do Espectro Autista/genética , Transtorno Fonológico/genética , Proteínas Supressoras de Tumor/genética , Oxidorredutase com Domínios WW/genética , Adolescente , Adulto , Transtorno do Espectro Autista/etiologia , Criança , Variações do Número de Cópias de DNA/genética , Exoma/genética , Família , Feminino , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Pleiotropia Genética/genética , Predisposição Genética para Doença/genética , Humanos , Masculino , Herança Multifatorial/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Irmãos , Transtorno Fonológico/etiologia , Proteínas Supressoras de Tumor/metabolismo , Oxidorredutase com Domínios WW/metabolismo , Sequenciamento do Exoma/métodos
9.
PLoS Genet ; 14(9): e1007589, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30188888

RESUMO

Canine malignant melanoma, a significant cause of mortality in domestic dogs, is a powerful comparative model for human melanoma, but little is known about its genetic etiology. We mapped the genomic landscape of canine melanoma through multi-platform analysis of 37 tumors (31 mucosal, 3 acral, 2 cutaneous, and 1 uveal) and 17 matching constitutional samples including long- and short-insert whole genome sequencing, RNA sequencing, array comparative genomic hybridization, single nucleotide polymorphism array, and targeted Sanger sequencing analyses. We identified novel predominantly truncating mutations in the putative tumor suppressor gene PTPRJ in 19% of cases. No BRAF mutations were detected, but activating RAS mutations (24% of cases) occurred in conserved hotspots in all cutaneous and acral and 13% of mucosal subtypes. MDM2 amplifications (24%) and TP53 mutations (19%) were mutually exclusive. Additional low-frequency recurrent alterations were observed amidst low point mutation rates, an absence of ultraviolet light mutational signatures, and an abundance of copy number and structural alterations. Mutations that modulate cell proliferation and cell cycle control were common and highlight therapeutic axes such as MEK and MDM2 inhibition. This mutational landscape resembles that seen in BRAF wild-type and sun-shielded human melanoma subtypes. Overall, these data inform biological comparisons between canine and human melanoma while suggesting actionable targets in both species.


Assuntos
Melanoma/genética , Melanoma/veterinária , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/veterinária , Animais , Ciclo Celular/genética , Proliferação de Células/genética , Hibridização Genômica Comparativa , Análise Mutacional de DNA , Doenças do Cão/genética , Cães , Feminino , Masculino , Melanoma/sangue , Melanoma/patologia , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo , Transdução de Sinais/genética , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/patologia , Análise Serial de Tecidos
10.
Hum Genet ; 137(6-7): 459-470, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29955957

RESUMO

Congenital inner ear malformations affecting both the osseous and membranous labyrinth can have a devastating impact on hearing and language development. With the exception of an enlarged vestibular aqueduct, non-syndromic inner ear malformations are rare, and their underlying molecular biology has thus far remained understudied. To identify molecular factors that might be important in the developing inner ear, we adopted a family-based trio exome sequencing approach in young unrelated subjects with severe inner ear malformations. We identified two previously unreported de novo loss-of-function variants in GREB1L [c.4368G>T;p.(Glu1410fs) and c.982C>T;p.(Arg328*)] in two affected subjects with absent cochleae and eighth cranial nerve malformations. The cochlear aplasia in these affected subjects suggests that a developmental arrest or problem at a very early stage of inner ear development exists, e.g., during the otic pit formation. Craniofacial Greb1l RNA expression peaks in mice during this time frame (E8.5). It also peaks in the developing inner ear during E13-E16, after which it decreases in adulthood. The crucial function of Greb1l in craniofacial development is also evidenced in knockout mice, which develop severe craniofacial abnormalities. In addition, we show that Greb1l-/- zebrafish exhibit a loss of abnormal sensory epithelia innervation. An important role for Greb1l in sensory epithelia innervation development is supported by the eighth cranial nerve deficiencies seen in both affected subjects. In conclusion, we demonstrate that GREB1L is a key player in early inner ear and eighth cranial nerve development. Abnormalities in cochleovestibular anatomy can provide challenges for cochlear implantation. Combining a molecular diagnosis with imaging techniques might aid the development of individually tailored therapeutic interventions in the future.


Assuntos
Surdez/genética , Doenças do Labirinto/genética , Proteínas de Neoplasias/genética , Proteínas/genética , Proteínas de Peixe-Zebra/genética , Animais , Surdez/fisiopatologia , Modelos Animais de Doenças , Orelha Interna/crescimento & desenvolvimento , Orelha Interna/fisiopatologia , Células Epiteliais/patologia , Gânglios Parassimpáticos/crescimento & desenvolvimento , Gânglios Parassimpáticos/fisiopatologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Doenças do Labirinto/fisiopatologia , Proteínas de Membrana , Camundongos , Camundongos Knockout , Peixe-Zebra
11.
PLoS One ; 13(6): e0198256, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29870545

RESUMO

Enzastaurin is a Protein Kinase C-ß selective inhibitor that was developed to treat cancers. Protein Kinase C-ß is an important enzyme for a variety of neuronal functions; in particular, previous rodent studies have reported deficits in spatial and fear-conditioned learning and memory with lower levels of Protein Kinase C-ß. Due to Enzastaurin's mechanism of action, the present study investigated the consequences of Enzastaurin exposure on learning and memory in 12-month-old Fischer-344 male rats. Rats were treated daily with subcutaneous injections of either vehicle or Enzastaurin, and behaviorally tested using the spatial reference memory Morris Water Maze. Rats treated with Enzastaurin exhibited decreased overnight retention and poorer performance on the latter testing day, indicating a mild, but significant, memory impairment. There were no differences during the probe trial indicating that all animals were able to spatially localize the platform to the proper quadrant by the end of testing. RNA isolated from the hippocampus was analyzed using Next Generation Sequencing (Illumina). No statistically significant transcriptional differences were noted. Our findings suggest that acute Enzastaurin treatment can impair hippocampal-based learning and memory performance, with no effects on transcription in the hippocampus. We propose that care should be taken in future clinical trials that utilize Protein Kinase C-ß inhibitors, to monitor for possible cognitive effects, future research should examine if these effects are fully reversible.


Assuntos
Envelhecimento/metabolismo , Comportamento Animal/efeitos dos fármacos , Indóis/efeitos adversos , Transtornos da Memória , Memória/efeitos dos fármacos , Proteína Quinase C beta/antagonistas & inibidores , Envelhecimento/genética , Animais , Indóis/farmacologia , Masculino , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/enzimologia , Proteína Quinase C beta/genética , Proteína Quinase C beta/metabolismo , Ratos , Ratos Endogâmicos F344
12.
J Appl Physiol (1985) ; 124(6): 1529-1540, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29543133

RESUMO

Aerobic (AE) and resistance exercise (RE) elicit unique adaptations in skeletal muscle that have distinct implications for health and performance. The purpose of this study was to identify the unique transcriptome response of skeletal muscle to acute AE and RE. In a counterbalanced, crossover design, six healthy, recreationally active young men (27 ± 3 yr) completed acute AE (40 min of cycling, ∼70% maximal HR) and RE [8 sets, 10 reps, ∼65% 1-repetition maximum (1RM)], separated by ∼1 wk. Muscle biopsies (vastus lateralis) were obtained before and at 1 and 4 h postexercise. Whole transcriptome RNA sequencing (HiSeq2500; Illumina) was performed on cDNA synthesized from skeletal muscle RNA. Sequencing data were analyzed using HTSeq, and differential gene expression was identified using DESeq2 [adjusted P value (FDR) <0.05, >1.5-fold change from preexercise]. RE resulted in a greater number of differentially expressed genes at 1 (67 vs. 48) and 4 h (523 vs. 221) compared with AE. We identified 348 genes that were differentially expressed only following RE, whereas 48 genes were differentially expressed only following AE. Gene clustering indicated that AE targeted functions related to zinc interaction, angiogenesis, and ubiquitination, whereas RE targeted functions related to transcription regulation, cytokine activity, cell adhesion, kinase activity, and the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. ESRRG and TNFSRF12A were identified as potential targets related to the specific response of skeletal muscle to AE and RE, respectively. These data describe the early postexercise transcriptome response of skeletal muscle to acute AE and RE and further highlight that different forms of exercise stimulate unique molecular activity in skeletal muscle. NEW & NOTEWORTHY Whole transcriptome RNA sequencing was used to determine the early postexercise transcriptome response of skeletal muscle to acute aerobic (AE) and resistance exercise (RE) in untrained individuals. Although a number of shared genes were stimulated following both AE and RE, several genes were uniquely responsive to each exercise mode. These findings support the need for future research focused to better identify the role of exercise mode as it relates to targeting specific cellular skeletal muscle abnormalities.


Assuntos
Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Transcriptoma , Adulto , Voluntários Saudáveis , Humanos , Masculino , Treinamento Resistido , Sequenciamento do Exoma , Adulto Jovem
13.
Am J Hum Genet ; 101(5): 716-724, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29100085

RESUMO

DHX30 is a member of the family of DExH-box helicases, which use ATP hydrolysis to unwind RNA secondary structures. Here we identified six different de novo missense mutations in DHX30 in twelve unrelated individuals affected by global developmental delay (GDD), intellectual disability (ID), severe speech impairment and gait abnormalities. While four mutations are recurrent, two are unique with one affecting the codon of one recurrent mutation. All amino acid changes are located within highly conserved helicase motifs and were found to either impair ATPase activity or RNA recognition in different in vitro assays. Moreover, protein variants exhibit an increased propensity to trigger stress granule (SG) formation resulting in global translation inhibition. Thus, our findings highlight the prominent role of translation control in development and function of the central nervous system and also provide molecular insight into how DHX30 dysfunction might cause a neurodevelopmental disorder.


Assuntos
Deficiências do Desenvolvimento/genética , Mutação de Sentido Incorreto/genética , RNA Helicases/genética , Adenosina Trifosfatases/genética , Adolescente , Aminoácidos/genética , Linhagem Celular , Linhagem Celular Tumoral , Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Feminino , Células HEK293 , Humanos , Deficiência Intelectual/genética , Masculino , RNA/genética
14.
J Neurosci ; 36(42): 10750-10758, 2016 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-27798130

RESUMO

Ventral regions of the medulla oblongata of the brainstem are populated by astrocytes sensitive to physiological changes in PCO2/[H+]. These astrocytes respond to decreases in pH with elevations in intracellular Ca2+ and facilitated exocytosis of ATP-containing vesicles. Released ATP propagates Ca2+ excitation among neighboring astrocytes and activates neurons of the brainstem respiratory network triggering adaptive increases in breathing. The mechanisms linking increases in extracellular and/or intracellular PCO2/[H+] with Ca2+ responses in chemosensitive astrocytes remain unknown. Fluorescent imaging of changes in [Na+]i and/or [Ca2+]i in individual astrocytes was performed in organotypic brainstem slice cultures and acute brainstem slices of adult rats. It was found that astroglial [Ca2+]i responses triggered by decreases in pH are preceded by Na+ entry, markedly reduced by inhibition of Na+/HCO3- cotransport (NBC) or Na+/Ca2+ exchange (NCX), and abolished in Na+-free medium or by combined NBC/NCX blockade. Acidification-induced [Ca2+]i responses were also dramatically reduced in brainstem astrocytes of mice deficient in the electrogenic Na+/HCO3- cotransporter NBCe1. Sensitivity of astrocytes to changes in pH was not affected by inhibition of Na+/H+ exchange or blockade of phospholipase C. These results suggest that in pH-sensitive astrocytes, acidification activates NBCe1, which brings Na+ inside the cell. Raising [Na+]i activates NCX to operate in a reverse mode, leading to Ca2+ entry followed by activation of downstream signaling pathways. Coupled NBC and NCX activities are, therefore, suggested to be responsible for functional CO2/H+ sensitivity of astrocytes that contribute to homeostatic regulation of brain parenchymal pH and control of breathing. SIGNIFICANCE STATEMENT: Brainstem astrocytes detect physiological changes in pH, activate neurons of the neighboring respiratory network, and contribute to the development of adaptive respiratory responses to the increases in the level of blood and brain PCO2/[H+]. The mechanisms underlying astroglial pH sensitivity remained unknown and here we show that in brainstem astrocytes acidification activates Na+/HCO3- cotransport, which brings Na+ inside the cell. Raising [Na+]i activates the Na+/Ca2+ exchanger to operate in a reverse mode leading to Ca2+ entry. This identifies a plausible mechanism of functional CO2/H+ sensitivity of brainstem astrocytes, which play an important role in homeostatic regulation of brain pH and control of breathing.


Assuntos
Astrócitos/efeitos dos fármacos , Dióxido de Carbono/farmacologia , Hidrogênio/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Astrócitos/metabolismo , Bicarbonatos/metabolismo , Sinalização do Cálcio , Exocitose , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Ratos , Respiração , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sódio/metabolismo , Simportadores de Sódio-Bicarbonato/antagonistas & inibidores , Simportadores de Sódio-Bicarbonato/genética , Simportadores de Sódio-Bicarbonato/metabolismo , Trocador de Sódio e Cálcio/antagonistas & inibidores , Trocador de Sódio e Cálcio/metabolismo
16.
Hum Mutat ; 37(8): 812-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27068579

RESUMO

Although there are nearly 100 different causative genes identified for nonsyndromic hearing loss (NSHL), Sanger sequencing-based DNA diagnostics usually only analyses three, namely, GJB2, SLC26A4, and OTOF. As this is seen as inadequate, there is a need for high-throughput diagnostic methods to detect disease-causing variations, including single-nucleotide variations (SNVs), insertions/deletions (Indels), and copy-number variations (CNVs). In this study, a targeted resequencing panel for hearing loss was developed including 79 genes for NSHL and selected forms of syndromic hearing loss. One-hundred thirty one presumed autosomal-recessive NSHL (arNSHL) patients of Western-European ethnicity were analyzed for SNVs, Indels, and CNVs. In addition, we established a straightforward variant classification system to deal with the large number of variants encountered. We estimate that combining prescreening of GJB2 with our panel leads to a diagnosis in 25%-30% of patients. Our data show that after GJB2, the most commonly mutated genes in a Western-European population are TMC1, MYO15A, and MYO7A (3.1%). CNV analysis resulted in the identification of causative variants in two patients in OTOA and STRC. One of the major challenges for diagnostic gene panels is assigning pathogenicity for variants. A collaborative database collecting all identified variants from multiple centers could be a valuable resource for hearing loss diagnostics.


Assuntos
Predisposição Genética para Doença , Perda Auditiva Neurossensorial/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação , Análise de Sequência de DNA/métodos , Conexina 26 , Conexinas/genética , Variações do Número de Cópias de DNA , Exoma , Proteínas Ligadas por GPI/genética , Perda Auditiva Neurossensorial/genética , Humanos , Mutação INDEL , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Membrana/genética , Miosina VIIa , Miosinas/genética , Polimorfismo de Nucleotídeo Único
17.
Hypertens Res ; 39(1): 8-18, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26490086

RESUMO

We have previously demonstrated that angiotensin-converting enzyme (ACE) inhibition with enalapril produces persistent effects that protect against future nitric oxide synthase (NOS) inhibitor (L-arginine methyl ester, L-NAME)-induced cardiac dysfunction and outer wall collagen deposition in spontaneously hypertensive rats (SHR). In the present study, we dissect the cytokine/chemokine release profile during NOS inhibition, its correlation to pathological cardiac remodeling and the impact of transient ACE inhibition on these effects. Adult male SHR were treated with enalapril (E+L) or tap water (C+L) for 2 weeks followed by a 2-week washout period. Rats were then subjected to 0, 3, 7 or 10 days of L-NAME treatment. The temporal response to NOS inhibition was evaluated by measuring arterial pressure, cardiac remodeling and cytokine/chemokine levels. L-NAME equivalently increased blood pressure and myocardial and vascular injury in C+L and E+L rats. However, pulse pressure (PP) was only transiently altered in C+L rats. The levels of several inflammatory mediators were increased during L-NAME treatment. However, interleukin-6 (IL-6) and IL-10 and monocyte chemoattractant protein-1 were uniquely increased in C+L hearts; whereas IL-4 and fractalkine were only elevated in E+L hearts. By days 7 and 10 of L-NAME treatment, there was a significant increase in the cardiac density of macrophages and proliferating cells, respectively only in C+L rats. Although myocardial injury was similar in both treatment groups, PP was not changed and there was a distinct cardiac chemokine/cytokine signature in rats previously treated with enalapril that may be related to the lack of proliferative response and macrophage infiltration in these hearts.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores Enzimáticos/farmacologia , Miocardite/patologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , Pressão Arterial/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quimiocina CCL2/sangue , Quimiocinas , Citocinas/metabolismo , Progressão da Doença , Enalapril/farmacologia , Interleucina-10/sangue , Interleucina-6/sangue , Macrófagos/efeitos dos fármacos , Masculino , Miocardite/induzido quimicamente , Miocardite/prevenção & controle , Ratos , Ratos Endogâmicos SHR
18.
Genome Res ; 25(11): 1646-55, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26232412

RESUMO

Canine transmissible venereal tumor (CTVT) is a parasitic cancer clone that has propagated for thousands of years via sexual transfer of malignant cells. Little is understood about the mechanisms that converted an ancient tumor into the world's oldest known continuously propagating somatic cell lineage. We created the largest existing catalog of canine genome-wide variation and compared it against two CTVT genome sequences, thereby separating alleles derived from the founder's genome from somatic mutations that must drive clonal transmissibility. We show that CTVT has undergone continuous adaptation to its transmissible allograft niche, with overlapping mutations at every step of immunosurveillance, particularly self-antigen presentation and apoptosis. We also identified chronologically early somatic mutations in oncogenesis- and immune-related genes that may represent key initiators of clonal transmissibility. Thus, we provide the first insights into the specific genomic aberrations that underlie CTVT's dogged perseverance in canids around the world.


Assuntos
Doenças do Cão/genética , Cães/genética , Estudos de Associação Genética , Tumores Venéreos Veterinários/genética , Animais , Apoptose , Autoantígenos/genética , Proteínas Adaptadoras de Sinalização CARD/genética , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Linhagem da Célula/genética , Colágeno Tipo XI/genética , Proteínas de Ligação a DNA/genética , Doenças do Cão/diagnóstico , Variação Genética , Genoma , Fatores de Troca do Nucleotídeo Guanina/genética , Proteoglicanas de Heparan Sulfato/genética , Proteínas dos Microfilamentos/genética , Mutação , Miotonina Proteína Quinase/genética , Filogenia , Análise de Componente Principal , Análise de Sequência de DNA , Tumores Venéreos Veterinários/diagnóstico
19.
PLoS One ; 10(7): e0131797, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26176221

RESUMO

A 3-year-old female patient presenting with an unknown syndrome of a neonatal progeroid appearance, lipodystrophy, pulmonary hypertension, cutis marmorata, feeding disorder and failure to thrive was investigated by whole-genome sequencing. This revealed a de novo, heterozygous, frame-shift mutation in the Caveolin1 gene (CAV1) (p.Phe160X). Mutations in CAV1, encoding the main component of the caveolae in plasma membranes, cause Berardinelli-Seip congenital lipodystrophy type 3 (BSCL). Although BSCL is recessive, heterozygous carriers either show a reduced phenotype of partial lipodystrophy, pulmonary hypertension, or no phenotype. To investigate the pathogenic mechanisms underlying this syndrome in more depth, we performed next generation RNA sequencing of peripheral blood, which showed several dysregulated pathways in the patient that might be related to the phenotypic progeroid features (apoptosis, DNA repair/replication, mitochondrial). Secondly, we found a significant down-regulation of known Cav1 interaction partners, verifying the dysfunction of CAV1. Other known progeroid genes and lipodystrophy genes were also dysregulated. Next, western blotting of lysates of cultured fibroblasts showed that the patient shows a significantly decreased expression of wild-type CAV1 protein, demonstrating a loss-of-function mutation, though her phenotype is more severe that other heterozygotes with similar mutations. This phenotypic variety could be explained by differences in genetic background. Indications for this are supported by additional rare variants we found in AGPAT2 and LPIN1 lipodystrophy genes. CAV1, AGPAT2 and LPIN1 all play an important role in triacylglycerol (TAG) biosynthesis in adipose tissue, and the defective function in different parts of this pathway, though not all to the same extend, could contribute to a more severe lipoatrophic phenotype in this patient. In conclusion, we report, for the first time, an association of CAV1 dysfunction with a syndrome of severe premature aging and lipodystrophy. This may contribute to a better understanding of the aging process and pathogenic mechanisms that contribute to premature aging.


Assuntos
Caveolina 1/genética , Retardo do Crescimento Fetal/genética , Lipodistrofia Generalizada Congênita/genética , Progéria/genética , Aciltransferases/genética , Pré-Escolar , Códon sem Sentido , Feminino , Retardo do Crescimento Fetal/patologia , Mutação da Fase de Leitura , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lipodistrofia Generalizada Congênita/patologia , Fenótipo , Fosfatidato Fosfatase/genética , Progéria/patologia , Análise de Sequência de RNA , Índice de Gravidade de Doença
20.
Cancer Med ; 4(6): 871-86, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25720842

RESUMO

The primary objective of the study was to evaluate the feasibility and safety of a process which would utilize genome-wide expression data from tumor biopsies to support individualized treatment decisions. Current treatment options for recurrent neuroblastoma are limited and ineffective, with a survival rate of <10%. Molecular profiling may provide data which will enable the practitioner to select the most appropriate therapeutic option for individual patients, thus improving outcomes. Sixteen patients with neuroblastoma were enrolled of which fourteen were eligible for this study. Feasibility was defined as completion of tumor biopsy, pathological evaluation, RNA quality control, gene expression profiling, bioinformatics analysis, generation of a drug prediction report, molecular tumor board yielding a treatment plan, independent medical monitor review, and treatment initiation within a 21 day period. All eligible biopsies passed histopathology and RNA quality control. Expression profiling by microarray and RNA sequencing were mutually validated. The average time from biopsy to report generation was 5.9 days and from biopsy to initiation of treatment was 12.4 days. No serious adverse events were observed and all adverse events were expected. Clinical benefit was seen in 64% of patients as stabilization of disease for at least one cycle of therapy or partial response. The overall response rate was 7% and the progression free survival was 59 days. This study demonstrates the feasibility and safety of performing real-time genomic profiling to guide treatment decision making for pediatric neuroblastoma patients.


Assuntos
Terapia de Alvo Molecular/métodos , Recidiva Local de Neoplasia/terapia , Neuroblastoma/terapia , Adolescente , Antineoplásicos/uso terapêutico , Criança , Pré-Escolar , Doença Crônica , Estudos de Viabilidade , Feminino , Perfilação da Expressão Gênica/métodos , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Terapia de Alvo Molecular/efeitos adversos , Segurança do Paciente , Estudos Prospectivos , RNA Neoplásico/genética , Análise de Sequência de RNA/métodos , Tempo para o Tratamento , Resultado do Tratamento , Adulto Jovem
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