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1.
Comput Intell Neurosci ; 2022: 8168396, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35676969

RESUMEN

In recent years, significant advances in the development of computer vision technology have produced many platforms and systems that combine computer technology and sports-assisted training, including intelligent systems that are integrated with golf training and instruction. However, the existing intelligent systems for golf-assisted teaching usually use three-dimensional depth information, which will significantly increase the cost of intelligent systems. In this paper, the extraction of golf club slope is carried out on the basis of golf sport video capture using a common monocular camera in order to match the club slope information with the professional coach swing video information. At the same time, in order to facilitate the interframe matching, the joint point information is complemented using the projection approximation point algorithm, and the segmentation of the swing video is performed using the complemented human hand joints and the fixed characteristics of the golf swing. Then, in order to solve the problem that human joints will have the same joint angle under different movements, the human limb joint angles are defined and then the swing movements in the user video frames are evaluated.


Asunto(s)
Golf , Algoritmos , Fenómenos Biomecánicos , Humanos , Articulaciones , Movimiento
2.
Cell Stem Cell ; 28(5): 923-937.e4, 2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-33675690

RESUMEN

Adult neurogenesis plays critical roles in maintaining brain homeostasis and responding to neurogenic insults. However, the adult mammalian spinal cord lacks an intrinsic capacity for neurogenesis. Here we show that spinal cord injury (SCI) unveils a latent neurogenic potential of NG2+ glial cells, which can be exploited to produce new neurons and promote functional recovery after SCI. Although endogenous SOX2 is required for SCI-induced transient reprogramming, ectopic SOX2 expression is necessary and sufficient to unleash the full neurogenic potential of NG2 glia. Ectopic SOX2-induced neurogenesis proceeds through an expandable ASCL1+ progenitor stage and generates excitatory and inhibitory propriospinal neurons, which make synaptic connections with ascending and descending spinal pathways. Importantly, SOX2-mediated reprogramming of NG2 glia reduces glial scarring and promotes functional recovery after SCI. These results reveal a latent neurogenic potential of somatic glial cells, which can be leveraged for regenerative medicine.


Asunto(s)
Neuroglía , Traumatismos de la Médula Espinal , Animales , Neurogénesis , Recuperación de la Función , Médula Espinal
3.
J Neurosci ; 41(9): 2024-2038, 2021 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-33468570

RESUMEN

DYT1 dystonia is a hereditary neurologic movement disorder characterized by uncontrollable muscle contractions. It is caused by a heterozygous mutation in Torsin A (TOR1A), a gene encoding a membrane-embedded ATPase. While animal models provide insights into disease mechanisms, significant species-dependent differences exist since animals with the identical heterozygous mutation fail to show pathology. Here, we model DYT1 by using human patient-specific cholinergic motor neurons (MNs) that are generated through either direct conversion of patients' skin fibroblasts or differentiation of induced pluripotent stem cells (iPSCs). These human MNs with the heterozygous TOR1A mutation show reduced neurite length and branches, markedly thickened nuclear lamina, disrupted nuclear morphology, and impaired nucleocytoplasmic transport (NCT) of mRNAs and proteins, whereas they lack the perinuclear "blebs" that are often observed in animal models. Furthermore, we uncover that the nuclear lamina protein LMNB1 is upregulated in DYT1 cells and exhibits abnormal subcellular distribution in a cholinergic MNs-specific manner. Such dysregulation of LMNB1 can be recapitulated by either ectopic expression of the mutant TOR1A gene or shRNA-mediated downregulation of endogenous TOR1A in healthy control MNs. Interestingly, downregulation of LMNB1 can largely ameliorate all the cellular defects in DYT1 MNs. These results reveal the value of disease modeling with human patient-specific neurons and indicate that dysregulation of LMNB1, a crucial component of the nuclear lamina, may constitute a major molecular mechanism underlying DYT1 pathology.SIGNIFICANCE STATEMENT Inaccessibility to patient neurons greatly impedes our understanding of the pathologic mechanisms for dystonia. In this study, we employ reprogrammed human patient-specific motor neurons (MNs) to model DYT1, the most severe hereditary form of dystonia. Our results reveal disease-dependent deficits in nuclear morphology and nucleocytoplasmic transport (NCT). Most importantly, we further identify LMNB1 dysregulation as a major contributor to these deficits, uncovering a new pathologic mechanism for DYT1 dystonia.


Asunto(s)
Técnicas de Reprogramación Celular/métodos , Distonía Muscular Deformante/metabolismo , Lamina Tipo B/metabolismo , Neuronas Motoras/metabolismo , Adolescente , Adulto , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular/fisiología , Células Cultivadas , Distonía Muscular Deformante/genética , Femenino , Fibroblastos , Humanos , Células Madre Pluripotentes Inducidas , Masculino , Persona de Mediana Edad , Chaperonas Moleculares/genética , Neuronas Motoras/patología , Células-Madre Neurales , Adulto Joven
4.
Mol Neurodegener ; 15(1): 61, 2020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-33087140

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is an adult-onset mental disorder with aging as a major risk factor. Early and progressive degeneration of basal forebrain cholinergic neurons (BFCNs) contributes substantially to cognitive impairments of AD. An aging-relevant cell model of BFCNs will critically help understand AD and identify potential therapeutics. Recent studies demonstrate that induced neurons directly reprogrammed from adult human skin fibroblasts retain aging-associated features. However, human induced BFCNs (hiBFCNs) have yet to be achieved. METHODS: We examined a reprogramming procedure for the generation of aging-relevant hiBFCNs through virus-mediated expression of fate-determining transcription factors. Skin fibroblasts were obtained from healthy young persons, healthy adults and sporadic AD patients. Properties of the induced neurons were examined by immunocytochemistry, qRT-PCR, western blotting, and electrophysiology. RESULTS: We established a protocol for efficient generation of hiBFCNs from adult human skin fibroblasts. They show electrophysiological properties of mature neurons and express BFCN-specific markers, such as CHAT, p75NTR, ISL1, and VACHT. As a proof-of-concept, our preliminary results further reveal that hiBFCNs from sporadic AD patients exhibit time-dependent TAU hyperphosphorylation in the soma and dysfunctional nucleocytoplasmic transport activities. CONCLUSIONS: Aging-relevant BFCNs can be directly reprogrammed from human skin fibroblasts of healthy adults and sporadic AD patients. They show promises as an aging-relevant cell model for understanding AD pathology and may be employed for therapeutics identification for AD.


Asunto(s)
Enfermedad de Alzheimer , Prosencéfalo Basal , Técnicas de Reprogramación Celular/métodos , Neuronas Colinérgicas , Envejecimiento/metabolismo , Envejecimiento/patología , Fibroblastos , Humanos
5.
Eur Respir J ; 54(2)2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31151959

RESUMEN

INTRODUCTION: Traditional thoracic ultrasound (TUS) is often the initial tool used to help diagnose malignant pleural effusion (MPE). Ultrasound elastography, a relatively new technique, has been used to differentiate malignant disease from benign disease by evaluating tissue "stiffness". However, no studies evaluating the efficacy of ultrasound elastography for diagnosing MPE are available. We assessed the value of ultrasound elsatography for diagnosing MPE prospectively. METHODS: All 244 enrolled patients were divided into a development set and a validation set in chronological order. The cut-off elasticity index was established using a receiver operating characteristic curve constructed from the continuous data of the patients in the development set. The diagnostic performance of ultrasound elastography was compared with that of TUS in the validation set. RESULTS: In the development set, the mean elasticity index (47.25 kPa) was the optimal cut-off. In the validation set, pleural ultrasound elastography had a sensitivity of 83.64%, a specificity of 90.67%, a positive predictive value of 86.79%, a negative predictive value of 88.31%, a positive likelihood ratio of 8.96 and a negative likelihood ratio of 0.18 for diagnosing MPE. The sensitivity of ultrasound elastography was significantly higher (p=0.006) than that of TUS (60%). CONCLUSION: Pleural ultrasound elastography is a better technique than TUS for differentiating MPE from benign pleural disease.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Derrame Pleural Maligno/diagnóstico por imagen , Derrame Pleural/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Elasticidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Sensibilidad y Especificidad , Adulto Joven
6.
Stem Cell Reports ; 11(5): 1156-1170, 2018 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30318292

RESUMEN

Neuronal subtype is largely fixed in the adult mammalian brain. Here, however, we unexpectedly reveal that adult mouse striatal neurons can be reprogrammed into dopaminergic neuron-like cells (iDALs). This in vivo phenotypic reprogramming can be promoted by a stem cell factor (SOX2), three dopaminergic neuron-enriched transcription regulators (NURR1, LMX1A, and FOXA2), and a chemical compound (valproic acid). Although the site of action of the reprogramming factors remains to be determined, immunohistochemistry and genetic lineage mappings confirm striatal neurons as the cell origin for iDALs. iDALs exhibit electrophysiological properties stereotypical to endogenous dopaminergic rather than striatal neurons. Together, these results indicate that neuronal phenotype can be reengineered even in the adult brain, implicating a therapeutic strategy for neurological diseases.


Asunto(s)
Envejecimiento/fisiología , Reprogramación Celular , Cuerpo Estriado/citología , Neuronas Dopaminérgicas/citología , Potenciales de Acción , Animales , Biomarcadores/metabolismo , Proliferación Celular , Células HEK293 , Humanos , Ventrículos Laterales/citología , Ratones Transgénicos , Neuroglía/citología , Neuroglía/metabolismo , Fenotipo
7.
Nat Commun ; 8(1): 1668, 2017 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-29162814

RESUMEN

Adult neurogenesis persists in the rodent dentate gyrus and is stimulated by chronic treatment with conventional antidepressants through BDNF/TrkB signaling. Ketamine in low doses produces both rapid and sustained antidepressant effects in patients. Previous studies have shed light on post-transcriptional synaptic NMDAR mediated mechanisms underlying the acute effect, but how ketamine acts at the cellular level to sustain this anti-depressive function for prolonged periods remains unclear. Here we report that ketamine accelerates differentiation of doublecortin-positive adult hippocampal neural progenitors into functionally mature neurons. This process requires TrkB-dependent ERK pathway activation. Genetic ablation of TrkB in neural stem/progenitor cells, or pharmacologic disruption of ERK signaling, or inhibition of adult neurogenesis, each blocks the ketamine-induced behavioral responses. Conversely, enhanced ERK activity via Nf1 gene deletion extends the response and rescues both neurogenic and behavioral deficits in mice lacking TrkB. Thus, TrkB-dependent neuronal differentiation is involved in the sustained antidepressant effects of ketamine.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Ketamina/farmacología , Células-Madre Neurales/metabolismo , Receptor trkB/metabolismo , Analgésicos/farmacología , Animales , Conducta Animal/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Femenino , Hipocampo/citología , Masculino , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Células-Madre Neurales/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/fisiología , Receptor trkB/genética
8.
Front Mol Neurosci ; 10: 359, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29163034

RESUMEN

In vitro generation of motor neurons (MNs) is a promising approach for modeling motor neuron diseases (MNDs) such as amyotrophic lateral sclerosis (ALS). As aging is a leading risk factor for the development of neurodegeneration, it is important to recapitulate age-related characteristics by using MNs at pathogenic ages. So far, cell reprogramming through induced pluripotent stem cells (iPSCs) and direct reprogramming from primary fibroblasts are two major strategies to obtain populations of MNs. While iPSC generation must go across the epigenetic landscape toward the pluripotent state, directly converted MNs might have the advantage of preserving aging-associated features from fibroblast donors. In this study, we confirmed that human iPSCs reset the aging status derived from their old donors, such as telomere attrition and cellular senescence. We then applied a set of transcription factors to induce MNs from either primary fibroblasts or iPSC-derived neural progenitor cells. The results revealed that directly reprogrammed MNs, rather than iPSC-derived MNs, maintained the aging hallmarks of old donors, including extensive DNA damage, loss of heterochromatin and nuclear organization, and increased SA-ß-Gal activity. iPSC-derived MNs did not regain those aging memories from old donors. Collectively, our study indicates rejuvenation in the iPSC-based model, as well as aging maintenance in direct reprogramming of MNs. As such, the directly reprogrammed MNs may be more suitable for modeling the late-onset pathogenesis of MNDs.

9.
Cell Rep ; 14(1): 115-128, 2016 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-26725112

RESUMEN

Subtype-specific neurons obtained from adult humans will be critical to modeling neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS). Here, we show that adult human skin fibroblasts can be directly and efficiently converted into highly pure motor neurons without passing through an induced pluripotent stem cell stage. These adult human induced motor neurons (hiMNs) exhibit the cytological and electrophysiological features of spinal motor neurons and form functional neuromuscular junctions (NMJs) with skeletal muscles. Importantly, hiMNs converted from ALS patient fibroblasts show disease-specific degeneration manifested through poor survival, soma shrinkage, hypoactivity, and an inability to form NMJs. A chemical screen revealed that the degenerative features of ALS hiMNs can be remarkably rescued by the small molecule kenpaullone. Taken together, our results define a direct and efficient strategy to obtain disease-relevant neuronal subtypes from adult human patients and reveal their promising value in disease modeling and drug identification.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Técnicas de Reprogramación Celular , Fibroblastos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Neuronas Motoras/metabolismo , Unión Neuromuscular/metabolismo , Adulto , Esclerosis Amiotrófica Lateral/patología , Animales , Fibroblastos/patología , Humanos , Células Madre Pluripotentes Inducidas/patología , Ratones , Neuronas Motoras/patología , Unión Neuromuscular/patología
10.
Oncol Lett ; 10(1): 543-549, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26171066

RESUMEN

The aim of the present study was to elucidate the molecular mechanisms of fibroblast growth factor receptor 3 (FGFR3) activation via overexpression or mutation of the FGFR3 target gene in bladder cancer (BC). The transcription profile data GSE41035, which included 18 BC samples, containing 3 independent FGFR3 short hairpin (sh)RNA, and 6 control samples, containing enhanced green fluorescent protein (EGFP) shRNA, were obtained from the National Center of Biotechnology Information Gene Expression Omnibus database. The Limma package with multiple testing correction was used to identify differentially expressed genes (DEGs) between FGFR3 knockdown and control samples. Gene ontology (GO) and pathway enrichment analysis were conducted in order to investigate the DEGs at the functional level. In addition, differential co-expression analysis was employed to construct a gene co-expression network. A total of 196 DEGs were acquired, of which 101 were downregulated and 95 were upregulated. In addition, a gene signature was identified linking FGFR3 signaling with de novo sterol biosynthesis and metabolism using GO and pathway enrichment analysis. Furthermore, the present study demonstrated that the genes NME2, CCNB1 and H2AFZ were significantly associated with BC, as determined by the protein-protein interaction network of DEGs and co-expressed genes. In conclusion, the present study revealed the involvement of FGFR3 in the regulation of sterol biosynthesis and metabolism in the maintenance of BC; in addition, the present study provided a novel insight into the molecular mechanisms of FGFR3 in BC. These results may therefore contribute to the theoretical guidance into the detection and therapy of BC.

11.
Stem Cell Reports ; 4(5): 780-94, 2015 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-25921813

RESUMEN

Glial cells can be in vivo reprogrammed into functional neurons in the adult CNS; however, the process by which this reprogramming occurs is unclear. Here, we show that a distinct cellular sequence is involved in SOX2-driven in situ conversion of adult astrocytes to neurons. This includes ASCL1(+) neural progenitors and DCX(+) adult neuroblasts (iANBs) as intermediates. Importantly, ASCL1 is required, but not sufficient, for the robust generation of iANBs in the adult striatum. These progenitor-derived iANBs predominantly give rise to calretinin(+) interneurons when supplied with neurotrophic factors or the small-molecule valproic acid. Patch-clamp recordings from the induced neurons reveal subtype heterogeneity, though all are functionally mature, fire repetitive action potentials, and receive synaptic inputs. Together, these results show that SOX2-mediated in vivo reprogramming of astrocytes to neurons passes through proliferative intermediate progenitors, which may be exploited for regenerative medicine.


Asunto(s)
Astrocitos/metabolismo , Encéfalo/metabolismo , Reprogramación Celular , Factores de Transcripción SOXB1/metabolismo , Animales , Astrocitos/citología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Calbindina 2/metabolismo , Proteína Doblecortina , Inmunohistoquímica , Interneuronas/citología , Interneuronas/metabolismo , Ratones , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neuronas/citología , Neuronas/metabolismo , Técnicas de Placa-Clamp , Factores de Transcripción SOXB1/genética
12.
Tumori ; 101(1): 117-22, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25702669

RESUMEN

AIMS AND BACKGROUND: Bladder carcinoma (BC) is one of the most common malignant cancers worldwide. Several genes related to the mechanism of BC have been studied in recent years, but the current understanding of BC is still rather limited. This study aimed to find new differentially expressed genes (DEGs) associated with the occurrence and development of BC. METHODS: In this work, we downloaded gene expression data from Gene Expression Omnibus under accession number GSE27448, which included 10 GeneChips from urinary BC tissues and 5 from normal tissues. DEGs were identified by the LIMMA package in R. Then the protein-protein interactions (PPIs) networks were analyzed with the database of Search Tool for the Retrieval of Interacting Genes, and gene ontology (GO) was applied to explore the underlying function of the DEGs using the Database for Annotation, Visualization and Integrated Discovery. RESULTS: A total of 2,068 DEGs were found between BC and normal tissues. These genes were involved in 49 functional clusters. The top 10 highest degree nodes, such as POLR2F/2H (DNA directed RNA polymerase II polypeptide F/polypeptide H) and RPS14/15 (ribosomal protein S14/S15), were proven to be hub nodes in the PPIs network. ITGA7 (integrin, alpha 7), GRB14 (growth factor receptor-bound protein 14), CDC20 (cell division cycle 20) and PSMB1 (proteasome subunit, beta type, 1) were significant DEGs identified in the functional clusters. CONCLUSIONS: Genes such as POLR2F/2H, RPS14/15, ITGA7, GRB14, CDC20 and PSMB1 were forecast to play important roles in the occurrence and progression of BC.


Asunto(s)
Biología Computacional , Perfilación de la Expresión Génica , Oncogenes , Neoplasias de la Vejiga Urinaria/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Antígenos CD/genética , Proteínas Cdc20/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Cadenas alfa de Integrinas/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Complejo de la Endopetidasa Proteasomal/genética , ARN Polimerasa II/genética , Proteínas Ribosómicas/genética
13.
Development ; 141(22): 4267-78, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25344074

RESUMEN

Various combinations of cardiogenic transcription factors, including Gata4 (G), Hand2 (H), Mef2c (M) and Tbx5 (T), can reprogram fibroblasts into induced cardiac-like myocytes (iCLMs) in vitro and in vivo. Given that optimal cardiac function relies on distinct yet functionally interconnected atrial, ventricular and pacemaker (PM) cardiomyocytes (CMs), it remains to be seen which subtypes are generated by direct reprogramming and whether this process can be harnessed to produce a specific CM of interest. Here, we employ a PM-specific Hcn4-GFP reporter mouse and a spectrum of CM subtype-specific markers to investigate the range of cellular phenotypes generated by reprogramming of primary fibroblasts. Unexpectedly, we find that a combination of four transcription factors (4F) optimized for Hcn4-GFP expression does not generate beating PM cells due to inadequate sarcomeric protein expression and organization. However, applying strict single-cell criteria to GHMT-reprogrammed cells, we observe induction of diverse cellular phenotypes, including those resembling immature forms of all three major cardiac subtypes (i.e. atrial, ventricular and pacemaker). In addition, we demonstrate that cells induced by GHMT are directly reprogrammed and do not arise from an Nxk2.5(+) progenitor cell intermediate. Taken together, our results suggest a remarkable degree of plasticity inherent to GHMT reprogramming and provide a starting point for optimization of CM subtype-specific reprogramming protocols.


Asunto(s)
Diferenciación Celular/fisiología , Inducción Embrionaria/fisiología , Fibroblastos/citología , Corazón/embriología , Miocitos Cardíacos/fisiología , Factores de Transcripción/metabolismo , Potenciales de Acción/fisiología , Análisis de Varianza , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cartilla de ADN/genética , Fibroblastos/metabolismo , Fibroblastos/fisiología , Factor de Transcripción GATA4/genética , Factor de Transcripción GATA4/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/metabolismo , Inmunohistoquímica , Factores de Transcripción MEF2/genética , Factores de Transcripción MEF2/metabolismo , Ratones , Miocitos Cardíacos/citología , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismo , Factores de Transcripción/genética
14.
Nat Cell Biol ; 15(10): 1164-75, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24056302

RESUMEN

Adult differentiated cells can be reprogrammed into pluripotent stem cells or lineage-restricted proliferating precursors in culture; however, this has not been demonstrated in vivo. Here, we show that the single transcription factor SOX2 is sufficient to reprogram resident astrocytes into proliferative neuroblasts in the adult mouse brain. These induced adult neuroblasts (iANBs) persist for months and can be generated even in aged brains. When supplied with BDNF and noggin or when the mice are treated with a histone deacetylase inhibitor, iANBs develop into electrophysiologically mature neurons, which functionally integrate into the local neural network. Our results demonstrate that adult astrocytes exhibit remarkable plasticity in vivo, a feature that might have important implications in regeneration of the central nervous system using endogenous patient-specific glial cells.


Asunto(s)
Astrocitos/citología , Reprogramación Celular/genética , Células-Madre Neurales/citología , Animales , Proliferación Celular , Proteína Ácida Fibrilar de la Glía/genética , Ratones , Ratones Transgénicos , Microscopía Confocal , Neuronas/citología , Regiones Promotoras Genéticas/genética , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Factores de Transcripción/metabolismo
15.
Nat Commun ; 4: 2183, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23873306

RESUMEN

Cell fate can be reprogrammed by modifying intrinsic and extrinsic cues. Here we show that two small molecules (forskolin and dorsomorphin) enable the transcription factor Neurogenin 2 (NGN2) to convert human fetal lung fibroblasts into cholinergic neurons with high purity (>90%) and efficiency (up to 99% of NGN2-expressing cells). The conversion is direct without passing through a proliferative progenitor state. These human induced cholinergic neurons (hiCN) show mature electrophysiological properties and exhibit motor neuron-like features, including morphology, gene expression and the formation of functional neuromuscular junctions. Inclusion of an additional transcription factor, SOX11, also efficiently converts postnatal and adult skin fibroblasts from healthy and diseased human patients to cholinergic neurons. Taken together, this study identifies a simple and highly efficient strategy for reprogramming human fibroblasts to subtype-specific neurons. These findings offer a unique venue for investigating the molecular mechanisms underlying cellular plasticity and human neurodegenerative diseases.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Neuronas Colinérgicas/efectos de los fármacos , Colforsina/farmacología , Fibroblastos/efectos de los fármacos , Proteínas del Tejido Nervioso/genética , Pirazoles/farmacología , Pirimidinas/farmacología , Factores de Transcripción SOXC/genética , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Adulto , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular , Neuronas Colinérgicas/citología , Neuronas Colinérgicas/metabolismo , Feto , Fibroblastos/citología , Fibroblastos/metabolismo , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Pulmón/citología , Pulmón/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Unión Neuromuscular/citología , Unión Neuromuscular/metabolismo , Cultivo Primario de Células , Factores de Transcripción SOXC/metabolismo , Factores de Tiempo
16.
Mol Cell Neurosci ; 56: 39-49, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23511190

RESUMEN

Rates of synapse formation and elimination change over the course of postnatal development, but little is known of molecular mechanisms that mediate this developmental switch. Here, we report that the dendritic RNA-binding protein fragile X mental retardation protein (FMRP) bidirectionally and cell autonomously regulates excitatory synaptic function, which depends on developmental age as well as function of the activity-dependent transcription factor myocyte enhancer factor 2 (MEF2). The acute postsynaptic expression of FMRP in CA1 neurons of hippocampal slice cultures (during the first postnatal week, P6-P7) promotes synapse function and maturation. In contrast, the acute expression of FMRP or endogenous FMRP in more mature neurons (during the second postnatal week; P13-P16) suppresses synapse number. The ability of neuronal depolarization to stimulate MEF2 transcriptional activity increases over this same developmental period. Knockout of endogenous MEF2 isoforms causes acute postsynaptic FMRP expression to promote, instead of eliminate, synapses onto 2-week-old neurons. Conversely, the expression of active MEF2 in neonatal neurons results in a precocious FMRP-dependent synapse elimination. Our findings suggest that FMRP and MEF2 function together to fine tune synapse formation and elimination rates in response to neuronal activity levels over the course of postnatal development.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Regulación del Desarrollo de la Expresión Génica , Factores de Transcripción MEF2/metabolismo , Sinapsis/metabolismo , Animales , Región CA1 Hipocampal/citología , Región CA1 Hipocampal/crecimiento & desarrollo , Región CA1 Hipocampal/metabolismo , Potenciales Postsinápticos Excitadores , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Factores de Transcripción MEF2/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/metabolismo , Neuronas/fisiología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sinapsis/fisiología , Transcripción Genética
17.
Cell Signal ; 25(1): 206-13, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23000344

RESUMEN

Here we studied the cellular mechanisms of ursolic acid's anti-bladder cancer ability by focusing on endoplasmic reticulum stress (ER stress) signaling. We show that ursolic acid induces a significant ER stress response in cultured human bladder cancer T24 cells. ER stress inhibitor salubrinal, or PERK silencing, diminishes ursolic acid-induced anti-T24 cell effects. Salubrinal inhibits ursolic acid-induced CHOP expression, Bim ER accumulation and caspase-3 activation in T24 cells. Ursolic acid induces IRE1-TRAF2-ASK1 signaling complex formation to activate pro-apoptotic ASK1-JNK signaling. We suggest that ER stress contributes to ursolic acid's effects against bladder cancer cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , MAP Quinasa Quinasa Quinasa 5/metabolismo , Triterpenos/farmacología , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Caspasa 3/metabolismo , Línea Celular Tumoral , Cinamatos/farmacología , Endorribonucleasas/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Transducción de Señal/efectos de los fármacos , Factor 2 Asociado a Receptor de TNF/metabolismo , Tiourea/análogos & derivados , Tiourea/farmacología , Factor de Transcripción CHOP/metabolismo , Neoplasias de la Vejiga Urinaria , eIF-2 Quinasa/antagonistas & inhibidores , eIF-2 Quinasa/genética , eIF-2 Quinasa/metabolismo , Ácido Ursólico
18.
Urol Int ; 90(3): 259-62, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23052323

RESUMEN

INTRODUCTION: Statins are cholesterol-lowering drugs that are widely used to prevent and treat atherosclerotic cardiovascular disease. It was found that statins can be associated with the occurrence of prostate cancer. However, no consensus has been concluded. MATERIALS AND METHODS: In the present study, we provide a refined meta-analysis on the association between statins and prostate cancers. Our objective is to offer a congruent recognition of the impact of statins on prostate cancer. RESULTS: Our refined analysis has included seven previous publications from the years 2005 to 2010. CONCLUSIONS: Based on the results, we concluded that there were associations for statin usage in preventing prostate cancer (OR 1.195, 95% CI 1.018-1.403, p = 0.029). Different from previous meta-analyses, our positive conclusion is primarily based on the recent new published literature, which supported the efficiency of statin use to control prostate cancer. More specific efforts for excluding the influence of other factors are crucial in further assessment of the efficiency of statin use.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Neoplasias de la Próstata/prevención & control , Humanos , Incidencia , Modelos Lineales , Masculino , Oportunidad Relativa , Neoplasias de la Próstata/epidemiología , Factores de Tiempo
19.
J Phys Chem B ; 116(29): 8412-22, 2012 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-22283547

RESUMEN

The amyloid-ß protein (Aß) oligomers are believed to be the main culprits in the cytoxicity of Alzheimer's disease (AD) and p3 peptides (Aß17-42 fragments) are present in AD amyloid plaques. Many small-molecule or peptide-based inhibitors are known to slow down Aß aggregation and reduce the toxicity in vitro, but their exact modes of action remain to be determined since there has been no atomic level of Aß(p3)-drug oligomers. In this study, we have determined the structure of Aß17-42 trimers both in aqueous solution and in the presence of five small-molecule inhibitors using a multiscale computational study. These inhibitors include 2002-H20, curcumin, EGCG, Nqtrp, and resveratrol. First, we used replica exchange molecular dynamics simulations coupled to the coarse-grained (CG) OPEP force field. These CG simulations reveal that the conformational ensemble of Aß17-42 trimer can be described by 14 clusters with each peptide essentially adopting turn/random coil configurations, although the most populated cluster is characterized by one peptide with a ß-hairpin at Phe19-Leu31. Second, these 14 dominant clusters and the less-frequent fibril-like state with parallel register of the peptides were subjected to atomistic Autodock simulations. Our analysis reveals that the drugs have multiple binding modes with different binding affinities for trimeric Aß17-42 although they interact preferentially with the CHC region (residues 17-21). The compounds 2002-H20 and Nqtrp are found to be the worst and best binders, respectively, suggesting that the drugs may interfere at different stages of Aß oligomerization. Finally, explicit solvent molecular dynamics of two predicted Nqtrp-Aß17-42 conformations describe at atomic level some possible modes of action for Nqtrp.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/química , Simulación del Acoplamiento Molecular , Fragmentos de Péptidos/antagonistas & inhibidores , Fragmentos de Péptidos/química , Multimerización de Proteína/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Enfermedad de Alzheimer/metabolismo , Secuencia de Aminoácidos , Péptidos beta-Amiloides/metabolismo , Humanos , Datos de Secuencia Molecular , Fragmentos de Péptidos/metabolismo , Conformación Proteica/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/química
20.
Neuron ; 66(2): 191-7, 2010 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-20434996

RESUMEN

Fragile X syndrome (FXS), the most common genetic form of mental retardation and autism, is caused by loss-of-function mutations in an RNA-binding protein, Fragile X Mental Retardation Protein (FMRP). Neurons from patients and the mouse Fmr1 knockout (KO) model are characterized by an excess of dendritic spines, suggesting a deficit in excitatory synapse elimination. In response to neuronal activity, myocyte enhancer factor 2 (MEF2) transcription factors induce robust synapse elimination. Here, we demonstrate that MEF2 activation fails to eliminate functional or structural excitatory synapses in hippocampal neurons from Fmr1 KO mice. Similarly, inhibition of endogenous MEF2 increases synapse number in wild-type but not Fmr1 KO neurons. MEF2-dependent synapse elimination is rescued in Fmr1 KO neurons by acute postsynaptic expression of wild-type but not RNA-binding mutants of FMRP. Our results reveal that active MEF2 and FMRP function together in an acute, cell-autonomous mechanism to eliminate excitatory synapses.


Asunto(s)
Espinas Dendríticas/metabolismo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Hipocampo/metabolismo , Factores Reguladores Miogénicos/metabolismo , Sinapsis/metabolismo , Animales , Espinas Dendríticas/genética , Potenciales Postsinápticos Excitadores/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Factores de Transcripción MEF2 , Ratones , Ratones Noqueados , Microscopía de Fluorescencia por Excitación Multifotónica , Potenciales Postsinápticos Miniatura/genética , Factores Reguladores Miogénicos/genética , Red Nerviosa/metabolismo , Plasticidad Neuronal/genética , Neuronas/metabolismo , Técnicas de Cultivo de Órganos , Técnicas de Placa-Clamp , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Sinapsis/genética , Transcripción Genética/genética , Transfección
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