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1.
Nat Commun ; 11(1): 3343, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620905

RESUMO

The expanded polyglutamine (polyQ) tract form of ataxin-1 drives disease progression in spinocerebellar ataxia type 1 (SCA1). Although known to form distinctive intranuclear bodies, the cellular pathways and processes that polyQ-ataxin-1 influences remain poorly understood. Here we identify the direct and proximal partners constituting the interactome of ataxin-1[85Q] in Neuro-2a cells, pathways analyses indicating a significant enrichment of essential nuclear transporters, pointing to disruptions in nuclear transport processes in the presence of elevated levels of ataxin-1. Our direct assessments of nuclear transporters and their cargoes confirm these observations, revealing disrupted trafficking often with relocalisation of transporters and/or cargoes to ataxin-1[85Q] nuclear bodies. Analogous changes in importin-ß1, nucleoporin 98 and nucleoporin 62 nuclear rim staining are observed in Purkinje cells of ATXN1[82Q] mice. The results highlight a disruption of multiple essential nuclear protein trafficking pathways by polyQ-ataxin-1, a key contribution to furthering understanding of pathogenic mechanisms initiated by polyQ tract proteins.


Assuntos
Ataxina-1/metabolismo , Núcleo Celular/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Células de Purkinje/metabolismo , Transporte Ativo do Núcleo Celular/genética , Animais , Ataxina-1/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células HeLa , Humanos , Camundongos , Mutação , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Transporte Nucleocitoplasmático/genética , Peptídeos/genética , Ligação Proteica , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/metabolismo , Expansão das Repetições de Trinucleotídeos/genética
2.
Science ; 368(6490): 497-505, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32355025

RESUMO

Androgen deprivation is the cornerstone of prostate cancer treatment. It results in involution of the normal gland to ~90% of its original size because of the loss of luminal cells. The prostate regenerates when androgen is restored, a process postulated to involve stem cells. Using single-cell RNA sequencing, we identified a rare luminal population in the mouse prostate that expresses stemlike genes (Sca1 + and Psca +) and a large population of differentiated cells (Nkx3.1 +, Pbsn +). In organoids and in mice, both populations contribute equally to prostate regeneration, partly through androgen-driven expression of growth factors (Nrg2, Rspo3) by mesenchymal cells acting in a paracrine fashion on luminal cells. Analysis of human prostate tissue revealed similar differentiated and stemlike luminal subpopulations that likewise acquire enhanced regenerative potential after androgen ablation. We propose that prostate regeneration is driven by nearly all persisting luminal cells, not just by rare stem cells.


Assuntos
Androgênios/metabolismo , Próstata/fisiologia , Próstata/cirurgia , Neoplasias da Próstata/cirurgia , Regeneração , Antagonistas de Androgênios/uso terapêutico , Proteína de Ligação a Androgênios/genética , Animais , Antígenos de Neoplasias/genética , Ataxina-1/genética , Diferenciação Celular/genética , Proteínas Ligadas por GPI/genética , Expressão Gênica , Proteínas de Homeodomínio/genética , Humanos , Masculino , Células-Tronco Mesenquimais/fisiologia , Camundongos , Proteínas de Neoplasias/genética , Fatores de Crescimento Neural/genética , Tamanho do Órgão , Organoides/metabolismo , Organoides/fisiologia , Próstata/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Regeneração/genética , Análise de Sequência de RNA , Análise de Célula Única , Trombospondinas/genética , Fatores de Transcrição/genética
3.
Sci Rep ; 10(1): 1557, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005838

RESUMO

A mutant form of the ataxin-1 protein with an expanded polyglutamine (polyQ) tract is the underlying cause of the inherited neurodegenerative disease spinocerebellar ataxia 1 (SCA1). In probing the biophysical features of the nuclear bodies (NBs) formed by polyQ-ataxin-1, we defined ataxin-1 NBs as spherical liquid protein/RNA droplets capable of rapid fusion. We observed dynamic exchange of the ataxin-1 protein into these NBs; notably, cell exposure to a pro-oxidant stress could trigger a transition to slower ataxin-1 exchange, typical of a hydrogel state, which no longer showed the same dependence on RNA or sensitivity to 1,6-hexanediol. Furthermore, we could alter ataxin-1 exchange dynamics either through modulating intracellular ATP levels, RNA helicase inhibition, or siRNA-mediated depletion of select RNA helicases. Collectively, these findings reveal the tunable dynamics of the liquid RNA/protein droplets formed by polyQ-ataxin-1.


Assuntos
Ataxina-1/metabolismo , Gotículas Lipídicas/metabolismo , RNA/metabolismo , Ataxias Espinocerebelares/metabolismo , Animais , Ataxina-1/genética , Linhagem Celular Tumoral , Humanos , Fusão de Membrana , Camundongos , Modelos Moleculares , Mutação/genética , Peptídeos/química , Ligação Proteica , Ataxias Espinocerebelares/genética
4.
Cardiovasc Res ; 116(3): 566-575, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31119267

RESUMO

AIMS: Both progenitor and differentiated cells were previously shown to secrete cardioprotective substances, but so far there has been no direct comparison of the paracrine effects of the two cell types on heart failure. The study sought to compare the paracrine effect of selected progenitors and the corresponding non-progenitor mononuclear cardiac cells on the cardiac function of transgenic heart failure mice. In addition, we aimed to further enhance the paracrine effect of the cells via pretreatment with the heart failure mediator aldosterone. METHODS AND RESULTS: Transgenic heart failure mice were injected with the supernatant of murine cardiac stem cell antigen-1 positive (Sca-1+) and negative (Sca-1-) cells with or without aldosterone pretreatment. Cardiac function was determined using small animal magnetic resonance imaging. In addition, heart failure markers were determined using enzyme-linked immunosorbent assay, RT-PCR, and bead-based multiplexing assay. While only the secretome of aldosterone pretreated Sca-1+ cells led to a significant improvement in cardiac function, N-terminal pro brain natriuretic peptide plasma levels were significantly lower and galectin-1 levels significantly higher in mice that were treated with either kind of secretome compared with untreated controls. CONCLUSION: In this first direct comparison of the paracrine effects of progenitor cells and a heterogeneous population of mononuclear cardiac cells the supernatants of both cell types showed cardioprotective properties which might be of great relevance for endogenous repair. During heart failure raised aldosterone levels might further increase the paracrine effect of progenitor cells.


Assuntos
Ataxina-1/metabolismo , Insuficiência Cardíaca/metabolismo , Miocárdio/metabolismo , Comunicação Parácrina , Células-Tronco/metabolismo , Aldosterona/farmacologia , Animais , Ataxina-1/deficiência , Ataxina-1/genética , Células Cultivadas , Modelos Animais de Doenças , Feminino , Fibrose , Galectina 1/sangue , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Interleucina-12/sangue , Masculino , Camundongos Transgênicos , Miocárdio/patologia , Peptídeo Natriurético Encefálico/sangue , Comunicação Parácrina/efeitos dos fármacos , Fragmentos de Peptídeos/sangue , Fenótipo , Via Secretória , Transdução de Sinais , Células-Tronco/efeitos dos fármacos , Células-Tronco/patologia , Remodelação Ventricular
5.
Nucleosides Nucleotides Nucleic Acids ; 39(1-3): 185-194, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31645175

RESUMO

Trinucleotide repeats are responsible for many genetic diseases. Previous studies have shown that duplex RNAs (dsRNAs) can be used to target expression of a mutant repeat allele while leaving expression of the wild-type allele untouched, creating opportunities for allele-selective inhibition and better therapeutic outcomes. In contrast to successes with other genes, we report here that we cannot achieve allele-selective inhibition when targeting the expanded CAG repeat within Ataxin-1 (ATXN1), the cause of spinal cerebellar ataxia-1 (SCA1). The most likely explanation for this unfavorable outcome is that the mean CAG repeat number within wild-type ATXN1 is relatively high compared to other trinucleotide repeat diseases. Because the wild-type repeat number is high, it is likely that there is poor discrimination between the mutant and wild-type repeat and less opportunity for allele-selective inhibition across the entire spectrum of mutations found in SCA1 patients. Our data support the conclusion that the potential for multiple cooperative binding interactions is a critical factor governing allele-selective recognition of trinucleotide repeat genes by duplex RNAs. These results should be helpful in predicting which diseases and which patients are most likely to benefit from allele-selective targeting of expanded repeats.


Assuntos
Alelos , Ataxina-1/genética , Regulação da Expressão Gênica , Inativação Gênica , Oligonucleotídeos , Repetições de Trinucleotídeos , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Mutação , Interferência de RNA , RNA de Cadeia Dupla/genética
6.
Neurobiol Aging ; 87: 139.e1-139.e7, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31810584

RESUMO

We analyzed the frequency of intermediate alleles (IAs) in the ATXN1, ATXN2, and HTT genes in several neurodegenerative diseases. The study included 1126 patients with Alzheimer's disease (AD), 440 patients with frontotemporal dementia (FTD), and 610 patients with Parkinson's disease. In all cohorts, we genotyped ATXN1 and ATXN2 CAG repeats. In addition, in the FTD cohort, we determined the number of HTT CAG repeats. The frequency of HTT IAs was higher in patients with FTD (6.9%) versus controls (2.9%) and in the C9orf72 expansion noncarriers (7.2%) versus controls (2.9%), although the difference was nonsignificant after correction for multiple testing. Compared with controls, progressive nonfluent aphasia (PNFA) groups showed a significantly higher frequency of HTT IAs (13.6% vs. 2.9% controls). For the ATXN2 gene, we observed an increase in IA frequency in AD cases (AD 4.1% vs. controls 1.8%) and in the behavioral FTD group (4.8% vs. 1.8%). For the ATXN1 gene, we found a significant increase of IAs in patients with PNFA (18.6%) versus controls (6.7%). In conclusion, our work suggests that the HTT and ATXN1 IAS may contribute to PNFA pathogenesis and point to a link between ATXN2 IAS and AD.


Assuntos
Doença de Alzheimer/genética , Ataxina-1/genética , Ataxina-2/genética , Demência Frontotemporal/genética , Proteína Huntingtina/genética , Doença de Parkinson/genética , Repetições de Trinucleotídeos , Proteína C9orf72/genética , Estudos de Coortes , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Expansão das Repetições de Trinucleotídeos
7.
BMC Med Genomics ; 12(1): 145, 2019 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655597

RESUMO

BACKGROUND: Wild-type (wt) polyglutamine (polyQ) regions are implicated in stabilization of protein-protein interactions (PPI). Pathological polyQ expansion, such as that in human Ataxin-1 (ATXN1), that causes spinocerebellar ataxia type 1 (SCA1), results in abnormal PPI. For ATXN1 a larger number of interactors has been reported for the expanded (82Q) than the wt (29Q) protein. METHODS: To understand how the expanded polyQ affects PPI, protein structures were predicted for wt and expanded ATXN1, as well as, for 71 ATXN1 interactors. Then, the binding surfaces of wt and expanded ATXN1 with the reported interactors were inferred. RESULTS: Our data supports that the polyQ expansion alters the ATXN1 conformation and that it enhances the strength of interaction with ATXN1 partners. For both ATXN1 variants, the number of residues at the predicted binding interface are greater after the polyQ, mainly due to the AXH domain. Moreover, the difference in the interaction strength of the ATXN1 variants was due to an increase in the number of interactions at the N-terminal region, before the polyQ, for the expanded form. CONCLUSIONS: There are three regions at the AXH domain that are essential for ATXN1 PPI. The N-terminal region is responsible for the strength of the PPI with the ATXN1 variants. How the predicted motifs in this region affect PPI is discussed, in the context of ATXN1 post-transcriptional modifications.


Assuntos
Ataxina-1/metabolismo , Motivos de Aminoácidos , Animais , Ataxina-1/química , Ataxina-1/genética , Sítios de Ligação , Humanos , Simulação de Acoplamento Molecular , Peptídeos/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Terciária de Proteína , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/patologia
8.
Stem Cell Res Ther ; 10(1): 294, 2019 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547879

RESUMO

INTRODUCTION: Accumulation of vascular smooth muscle cells (VSMCs) within the neointimal region is a hallmark of atherosclerosis and vessel injury. Evidence has shown that Sca-1-positive (Sca-1+) progenitor cells residing in the vascular adventitia play a crucial role in VSMC assemblages and intimal lesions. However, the underlying mechanisms, especially in the circumstances of vascular injury, remain unknown. METHODS AND RESULTS: The neointimal formation model in rats was established by carotid artery balloon injury using a 2F-Forgaty catheter. Most Sca-1+ cells first appeared at the adventitia of the vascular wall. S100B expressions were highest within the adventitia on the first day after vessel injury. Along with the sequentially increasing trend of S100B expression in the intima, media, and adventitia, respectively, the numbers of Sca-1+ cells were prominently increased at the media or neointima during the time course of neointimal formation. Furthermore, the Sca-1+ cells were markedly increased in the tunica media on the third day of vessel injury, SDF-1α expressions were obviously increased, and SDF-1α levels and Sca-1+ cells were almost synchronously increased within the neointima on the seventh day of vessel injury. These effects could effectually be reversed by knockdown of S100B by shRNA, RAGE inhibitor (SPF-ZM1), or CXCR4 blocker (AMD3100), indicating that migration of Sca-1+ cells from the adventitia into the neointima was associated with S100B/RAGE and SDF-1α/CXCR4. More importantly, the intermediate state of double-positive Sca-1+ and α-SMA cells was first found in the neointima of injured arteries, which could be substantially abrogated by using shRNA for S100B or blockade of CXCR4. S100B dose-dependently regulated SDF-1α expressions in VSMCs by activating PI3K/AKT and NF-κB, which were markedly abolished by PI3K/AKT inhibitor wortmannin and enhanced by p65 blocker PDTC. Furthermore, S100B was involved in human umbilical cord-derived Sca-1+ progenitor cells' differentiation into VSMCs, especially in maintaining the intermediate state of double-positive Sca-1+ and α-SMA. CONCLUSIONS: S100B triggered neointimal formation in rat injured arteries by maintaining the intermediate state of double-positive Sca-1+ progenitor and VSMCs, which were associated with direct activation of RAGE by S100B and indirect induction of SDF-1α by activating PI3K/AKT and NF-κB.


Assuntos
Ataxina-1/metabolismo , Lesões das Artérias Carótidas/metabolismo , Mioblastos/metabolismo , Miócitos de Músculo Liso/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Túnica Adventícia/citologia , Túnica Adventícia/fisiologia , Animais , Ataxina-1/genética , Lesões das Artérias Carótidas/patologia , Células Cultivadas , Humanos , Músculo Liso Vascular/citologia , Mioblastos/citologia , Miócitos de Músculo Liso/citologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Regeneração , Subunidade beta da Proteína Ligante de Cálcio S100/genética , Túnica Íntima/citologia , Túnica Íntima/fisiologia
9.
Stem Cells Dev ; 28(22): 1498-1513, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31530214

RESUMO

Cardiac progenitor cells (CPCs) in the adult mammalian heart, as well as exogenous CPCs injected at the border zone of infarcted tissue, display very low differentiation rate into cardiac myocytes and marginal repair capacity in the injured heart. Emerging evidence supports an obligatory metabolic shift from glycolysis to oxidative phosphorylation (OXPHOS) during stem cells differentiation, suggesting that pharmacological modulation of metabolism may improve CPC differentiation and, potentially, healing properties. In this study, we investigated the metabolic transition underlying CPC differentiation toward cardiac myocytes. In addition, we tested whether activators of adenosine monophosphate-activated protein kinase (AMPK), known to promote mitochondrial biogenesis in other cell types would also improve CPC differentiation. Stem cell antigen 1 (Sca1+) CPCs were isolated from adult mouse hearts and their phenotype compared with more mature neonatal rat cardiac myocytes (NRCMs). Under normoxia, glucose consumption and lactate release were significantly higher in CPCs than in NRCMs. Both parameters were increased in hypoxia together with increased abundance of Glut1 (glucose transporter), of the monocarboxylic transporter Mct4 (lactate efflux mediator) and of Pfkfb3 (key regulator of glycolytic rate). CPC proliferation was critically dependent on glucose and glutamine availability in the media. Oxygen consumption analysis indicates that, compared with NRCMs, CPCs exhibited lower basal and maximal respirations with lower Tomm20 protein expression and mitochondrial DNA content. This CPC metabolic phenotype profoundly changed upon in vitro differentiation, with a decrease of glucose consumption and lactate release together with increased abundance of Tnnt2, Pgc-1α, Tomm20, and mitochondrial DNA content. Proliferative CPCs express both alpha1 and -2 catalytic subunits of AMPK that is activated by A769662. However, A769662 or resveratrol (an activator of Pgc-1α and AMPK) did not promote either mitochondrial biogenesis or CPC maturation during their differentiation. We conclude that although CPC differentiation is accompanied with an increase of mitochondrial oxidative metabolism, this is not potentiated by activation of AMPK in these cells.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Traumatismos Cardíacos/metabolismo , Infarto do Miocárdio/metabolismo , Proteínas Quinases/genética , Animais , Ataxina-1/genética , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Glutamina/metabolismo , Glicólise/efeitos dos fármacos , Traumatismos Cardíacos/genética , Traumatismos Cardíacos/patologia , Traumatismos Cardíacos/terapia , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Transportadores de Ácidos Monocarboxílicos/genética , Proteínas Musculares/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Fosfofrutoquinase-2/genética , Pironas/farmacologia , Ratos , Resveratrol/farmacologia , Tiofenos/farmacologia
10.
Cell ; 178(5): 1159-1175.e17, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31442405

RESUMO

Expansion of CAG trinucleotide repeats in ATXN1 causes spinocerebellar ataxia type 1 (SCA1), a neurodegenerative disease that impairs coordination and cognition. While ATXN1 is associated with increased Alzheimer's disease (AD) risk, CAG repeat number in AD patients is not changed. Here, we investigated the consequences of ataxin-1 loss of function and discovered that knockout of Atxn1 reduced CIC-ETV4/5-mediated inhibition of Bace1 transcription, leading to increased BACE1 levels and enhanced amyloidogenic cleavage of APP, selectively in AD-vulnerable brain regions. Elevated BACE1 expression exacerbated Aß deposition and gliosis in AD mouse models and impaired hippocampal neurogenesis and olfactory axonal targeting. In SCA1 mice, polyglutamine-expanded mutant ataxin-1 led to the increase of BACE1 post-transcriptionally, both in cerebrum and cerebellum, and caused axonal-targeting deficit and neurodegeneration in the hippocampal CA2 region. These findings suggest that loss of ataxin-1 elevates BACE1 expression and Aß pathology, rendering it a potential contributor to AD risk and pathogenesis.


Assuntos
Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Ataxina-1/metabolismo , Encéfalo/metabolismo , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Ataxina-1/deficiência , Ataxina-1/genética , Encéfalo/patologia , Região CA2 Hipocampal/metabolismo , Região CA2 Hipocampal/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Feminino , Frequência do Gene , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neurogênese , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Genética , Repetições de Trinucleotídeos/genética , Regulação para Cima
11.
Neurotherapeutics ; 16(4): 999-1008, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31338702

RESUMO

The spinocerebellar ataxias (SCAs) are a group of neurodegenerative disorders inherited in an autosomal dominant fashion. The SCAs result in progressive gait imbalance, incoordination of the limbs, speech changes, and oculomotor dysfunction, among other symptoms. Over the past few decades, significant strides have been made in understanding the pathogenic mechanisms underlying these diseases. Although multiple efforts using a combination of genetics and pharmacology with small molecules have been made towards developing new therapeutics, no FDA approved treatment currently exists. In this review, we focus on SCA1, a common SCA subtype, in which some of the greatest advances have been made in understanding disease biology, and consequently potential therapeutic targets. Understanding of the underlying basic biology and targets of therapy in SCA1 is likely to give insight into treatment strategies in other SCAs. The diversity of the biology in the SCAs, and insight from SCA1 suggests, however, that both shared treatment strategies and specific approaches tailored to treat distinct genetic causes of SCA are likely needed for this group of devastating neurological disorders.


Assuntos
Ataxina-1/genética , Ensaios Clínicos como Assunto/métodos , Sistemas de Liberação de Medicamentos/tendências , Marcação de Genes/tendências , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/terapia , Animais , Ataxina-1/antagonistas & inibidores , Ataxina-1/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Fármacos Atuantes sobre Aminoácidos Excitatórios/administração & dosagem , Fármacos Atuantes sobre Aminoácidos Excitatórios/metabolismo , Marcação de Genes/métodos , Terapia Genética/métodos , Terapia Genética/tendências , Humanos , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/metabolismo , Interferência de RNA/efeitos dos fármacos , Interferência de RNA/fisiologia , Ataxias Espinocerebelares/metabolismo
12.
J Cell Biochem ; 120(10): 18533-18543, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31245874

RESUMO

To explore the formation, morphological characteristics, cell composition, and differentiation potential of cardiomyocyte annulation (cardio-annulation) during in vitro culture of cardiac cells. Cardiac cells were isolated and cultured. A live-cell imaging system was used to observe cardio-annulation. Cardiac troponin-T (cTnT) and vimentin were labeled with double immunofluorescence staining, and coexpressions of cTnT and connexin43 (Cx43), cTnT and nanog, c-kit and nanog, and c-kit and stem cell antigen (sca-1) were detected. The location of various types of cells within the cardio-annulation structure was observed. Adipogenic- and osteogenic-inducing fluids were used separately for in situ induction to detect the multidirectional differentiation potential of cells during the annulation process. After 3 to 6 days, cardiac cells migrated and formed an open or closed annulus with a diameter of 800 to 3500 µm. The annulus wall comprised the medial, middle, and lateral regions. The cells in the medial region were small, abundant, and laminated, while those in the middle region were larger with fewer layers, and those in the lateral region were less abundant, and loosely arranged in a single layer. Cardiomyocytes were distributed mainly on the surface of the medial region; nanog+ , c-kit+ , and sca-1+ cells were located mainly at the bottom of the annulus wall and fibroblasts were located mainly between these layers. The annulus cavity contained a large number of small, round cells, and telocytes. Cx43 was expressed in all cell types, and nanog, c-kit, and sca-1 were coexpressed in the cardio-annulation cells, which possess adipogenic and osteogenic differentiation potential. Cardio-annulation was discovered during an in vitro culture of cardiac cells. The structure contains cardiomyocytes, fibroblasts, telocytes, and abundant stem cells. These results provide insight into the relationship among cardiac cells in vitro.


Assuntos
Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Animais , Animais Recém-Nascidos , Ataxina-1/genética , Ataxina-1/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Conexina 43/genética , Conexina 43/metabolismo , Imunofluorescência , Osteócitos/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Troponina T/genética , Troponina T/metabolismo
13.
PLoS One ; 14(5): e0217394, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31136600

RESUMO

Recently, we showed that imidazole dipeptide such as carnosine contained abundantly in chicken breast meat improves brain function in a double-blind randomized controlled trial. However, the underlying molecular mechanisms remain unknown. Here, we investigated whether carnosine activates intestinal epithelial cells and induces the secretion of factors that activate brain function. We focused on exosomes derived from intestinal epithelial cells as mediators of brain-gut interaction. Results showed that exosomes derived from Caco-2 cells treated with carnosine significantly induced neurite growth in SH-SY5Y cells. To clarify the molecular basis of this finding, we performed integrated analysis of microRNAs (miRNAs) with altered expression in exosomes in response to carnosine treatment and mRNAs with altered expression in target cells in response to exosome treatment to identify related miRNAs and their target genes. The combination of miR-6769-5p and its target gene ATXN1 was found to be involved in the exosome-induced activation of neuronal cells.


Assuntos
Carnosina/farmacologia , Exossomos/efeitos dos fármacos , Exossomos/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Neurônios/metabolismo , Ataxina-1/genética , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células CACO-2 , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Exossomos/genética , Perfilação da Expressão Gênica , Humanos , Mucosa Intestinal/citologia , MicroRNAs/genética , MicroRNAs/metabolismo
14.
Front Immunol ; 10: 819, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068932

RESUMO

Stem Cell Antigen-1 (Sca-1/Ly6A) was the first identified member of the Lymphocyte antigen-6 (Ly6) gene family. Sca-1 serves as a marker of cancer stem cells and tissue resident stem cells in mice. The Sca-1 gene is located on mouse chromosome 15. While a direct homolog of Sca-1 in humans is missing, human chromosome 8-the syntenic region to mouse chromosome 15-harbors several genes containing the characteristic domain known as LU domain. The function of the LU domain in human LY6 gene family is not yet defined. The LY6 gene family proteins are present on human chromosome 6, 8, 11, and 19. The most interesting of these genes are located on chromosome 8q24.3, a frequently amplified locus in human cancer. Human LY6 genes represent novel biomarkers for poor cancer prognosis and are required for cancer progression in addition to playing an important role in immune escape. Although the mechanism associated with these phenotype is not yet clear, it is timely to review the current literature in order to address the critical need for future advancements in this field. This review will summarize recent findings which describe the role of human LY6 genes-LY6D, LY6E, LY6H, LY6K, PSCA, LYPD2, SLURP1, GML, GPIHBP1, and LYNX1; and their orthologs in mice at chromosome 15.


Assuntos
Ataxina-1/genética , Suscetibilidade a Doenças , Linfócitos/imunologia , Linfócitos/metabolismo , Família Multigênica , Neoplasias/etiologia , Neoplasias/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Neoplasias/mortalidade , Neoplasias/patologia , Especificidade de Órgãos
15.
Eur J Neurol ; 26(8): 1130-1136, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30891880

RESUMO

BACKGROUND AND PURPOSE: The expanded repeat length in ATXN1 negatively correlates with age at onset (AAO) of spinocerebellar ataxia type 1 (SCA1) but can explain only part of it, indicating that other factors affect AAO. Some studies have explored the influence of non-causative CAG repeats on the AAO of SCA patients. However, studies on Chinese SCA1 patients regarding candidate modifier factors involved in the variability in AAO are rare. METHODS: In all, 152 Chinese SCA1 patients who were genotyped for ATXN1 and nine other (CAG)n -containing genes were enrolled. Regression analysis was performed to determine the effect of the expanded allele of ATXN1 (linear and quadratic effects) on AAO. Then, different models were used to explore the modulatory effect of nine other (CAG)n -containing genes. RESULTS: Our results verified the negative effect of the expanded allele in ATXN1 by regression analysis. Some (CAG)n -containing genes including TBP, ATN1 and HTT modified AAO with variance ranging from 0.8% to 3.8% and tended to decrease or delay AAO. However, no modifier effects of ATXN2, ATXN3, CACNA1A, ATXN7, KCNN3, RAI1 and normal ATXN1 alleles in trans were detected. CONCLUSION: By using interaction analyses, TBP, ATN1 and HTT were determined to have modifying effects. Our study revealed that differences in modulation may be due to ethnic and geographic diversity across different populations. Furthermore, the variability of AAO was not completely explained by the genetic modifiers examined here, suggesting that other genetic or environmental factors are involved in these diseases.


Assuntos
Alelos , Ataxina-1/genética , Genótipo , Ataxias Espinocerebelares/genética , Expansão das Repetições de Trinucleotídeos/genética , Adolescente , Adulto , Idade de Início , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Ophthalmic Genet ; 40(1): 49-53, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30729852

RESUMO

BACKGROUND: Spinocerebellar ataxia type 1 (SCA1) caused by pathogenic CAG repeat expansion in the ATXN1 is characterized by loss of vision with little fundus abnormalities in some patients. Recently, macular degeneration has been reported to account for the visual symptoms in sporadic cases. MATERIALS AND METHODS: Five consecutive patients diagnosed as SCA1 with supporting genetical evidence were newly referred to ophthalmology department from neurology unit. They underwent ocular examination to assess visual acuity and the structural integrity of the macula using optical coherent tomography (OCT). Full-field and multifocal electroretinogram (ERG) were recorded in some patients. Genetic testing was done by a polymerase chain reaction-based method. RESULTS: Fundus examinations revealed normal optic disc and macula appearance. However, four out of five patients had foveal thinning by OCT. This included three patients who showed reduced visual acuity. Among the three, multifocal ERG was performed in two, which showed reduced amplitudes in the localized foveal area. Full-field ERG showed normal responses in all five patients assessed. Only one patient had normal visual function and normal macular structure. CONCLUSIONS: Macular degeneration with subtle funduscopic alterations, sometimes mimicking occult macular dystrophy, is an important cause of visual loss in SCA1 patients, which could be reliably detected with OCT and multifocal ERGs.


Assuntos
Ataxina-1/genética , Degeneração Macular/complicações , Mutação , Ataxias Espinocerebelares/fisiopatologia , Transtornos da Visão/etiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Transtornos da Visão/patologia , Acuidade Visual
19.
Neurobiol Aging ; 73: 230.e9-230.e17, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30314815

RESUMO

Genomewide association studies (GWASs) have contributed greatly to unraveling the genetic basis of Alzheimer's disease (AD). However, a large amount of "missing heritability" remains. In this exploratory study, we investigated the effect of cytosine-adenine-guanine (CAG) repeats in polyglutamine disease-associated genes (PDAGs) on the risk of AD and its expression. In a cohort of 959 patients diagnosed with AD (Amsterdam Dementia cohort) and 4106 cognitively healthy participants (Leiden 85-plus Study and the Prospective Study of Pravastatin in the Elderly at Risk), we determined the CAG repeat sequences in ATXN1, ATXN2, ATXN3, CACNA1A, ATXN7, TBP, HTT, ATN1, and AR. We did not find a significant association between the risk of AD and variations in CAG repeat numbers of PDAGs. However, we found that differences in CAG repeat numbers in ATXN1, ATXN2, and AR were significantly associated with several clinical and imaging features in AD patients. Specifically, the association between memory performance in patients with AD and the CAG repeat size in the longer ATXN1 allele, and the association between atrophy in the medial temporal lobes and the CAG repeat number in the longer AR allele remained significant after correction for multiple testing. Our findings suggest that repeat polymorphisms in ATXN1 and AR can act as important genetic modifiers of AD, warranting further scrutiny of their role in its missing heritability and pathogenesis.


Assuntos
Doença de Alzheimer/genética , Ataxina-1/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla , Polimorfismo Genético/genética , Receptores Androgênicos/genética , Adenina , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Citosina , Feminino , Guanina , Humanos , Masculino , Pessoa de Meia-Idade , Sequências Repetitivas de Ácido Nucleico , Lobo Temporal/patologia
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