Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Neurobiol Dis ; 188: 106346, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37931884

RESUMEN

Sprouting of mossy fibers, one of the most consistent findings in tissue from patients with mesial temporal lobe epilepsy, exhibits several uncommon axonal growth features and has been considered a paradigmatic example of circuit plasticity that occurs in the adult brain. Clarifying the mechanisms responsible may provide new insight into epileptogenesis as well as axon misguidance in the central nervous system. Methyl-CpG-binding protein 2 (MeCP2) binds to methylated genomic DNA to regulate a range of physiological functions implicated in neuronal development and adult synaptic plasticity. However, exploring the potential role of MeCP2 in the documented misguidance of axons in the dentate gyrus has not yet been attempted. In this study, a status epilepticus-induced decrease of neuronal MeCP2 was observed in the dentate gyrus (DG). An essential regulatory role of MeCP2 in the development of functional mossy fiber sprouting (MFS) was confirmed through stereotaxic injection of a recombinant adeno-associated virus (AAV) to up- or down-regulate MeCP2 in the dentate neurons. Chromatin immunoprecipitation sequencing (ChIP-seq) was performed to identify the binding profile of native MeCP2 using micro-dissected dentate tissues. In both dentate tissues and HT22 cell lines, we demonstrated that MeCP2 could act as a transcription repressor on miR-682 with the involvement of the DNA methylation mechanism. Further, we found that miR-682 could bind to mRNA of phosphatase and tensin homolog (PTEN) in a sequence specific manner, thus leading to the suppression of PTEN and excessive activation of mTOR. This study therefore presents a novel epigenetic mechanism by identifying MeCP2/miR-682/PTEN/mTOR as an essential signal pathway in regulating the formation of MFS in the temporal lobe epileptic (TLE) mice. SIGNIFICANCE STATEMENT: Understanding the mechanisms that regulate axon guidance is important for a better comprehension of neural disorders. Sprouting of mossy fibers, one of the most consistent findings in patients with mesial temporal lobe epilepsy, has been considered a paradigmatic example of circuit plasticity in the adult brain. Although abnormal regulation of DNA methylation has been observed in both experimental rodents and humans with epilepsy, the potential role of DNA methylation in this well-documented example of sprouting of dentate axon remains elusive. This study demonstrates an essential role of methyl-CpG-binding protein 2 in the formation of mossy fiber sprouting. The underlying signal pathway has been also identified. The data hence provide new insight into epileptogenesis as well as axon misguidance in the central nervous system.


Asunto(s)
Epilepsia del Lóbulo Temporal , Epilepsia , MicroARNs , Animales , Humanos , Ratones , Giro Dentado/metabolismo , Epilepsia del Lóbulo Temporal/metabolismo , Proteína 2 de Unión a Metil-CpG/genética , Proteína 2 de Unión a Metil-CpG/metabolismo , MicroARNs/metabolismo , Fibras Musgosas del Hipocampo , Serina-Treonina Quinasas TOR/metabolismo
2.
Biochem Biophys Res Commun ; 531(3): 275-281, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-32800559

RESUMEN

MicroRNAs (miRNA) are believed to play a crucial role in the cause and treatment of temporal lobe epilepsy (TLE) by controlling gene expression in different stages of the disease. To investigate role of miRNA in the latent stage following status epilepticus, we first compared microRNA expression profiles in mice hippocampus at 1 week after pilocarpine-induced status epilepticus (SE) vs. controls in hippocampal tissues using Exiqon miRCURY LNA™ miRNAs Array. Then, the target genes of altered miRNAs were predicted using both TargetScan 7.1 and miRDB V5, and were further selected by intersecting with another independent mRNA expression profile dataset from the samples at the same time point. We found out 14 common genes as down miRNA target (up-mRNA) and 4 common genes as up miRNA target (down mRNA) in SE mice. miR-669m-3p-TRHR (thyrotropin releasing hormone receptor), miR-669m-3p-B3galt2 (ß-1,3-Galactosyltransferase 2), miR-105-PDPN (Podoplanin) and miR-883b-3p-CLEC-2 (C-type-lectin-like-2) were found to be potential molecular mechanisms to modulate the calcium signaling pathway, glycosylation pathways and chemokine mediated inflammatory processes in mice hippocampus at 1 week after pilocarpine-induced SE, respectively. Our results offered potential novel insights into the cellular events in the mice hippocampus mediated by miRNASs-target genes that shape SE-evoked epileptogenesis.


Asunto(s)
Hipocampo/metabolismo , MicroARNs/metabolismo , Estado Epiléptico/inducido químicamente , Estado Epiléptico/genética , Animales , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Ontología de Genes , Ratones , MicroARNs/genética , Pilocarpina , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reproducibilidad de los Resultados
3.
Neurochem Res ; 44(11): 2590-2605, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31560103

RESUMEN

Increased number of newly-born neurons produced at latent stage after status epilepticus (SE) contribute to aberrant rewiring of hippocampus and are hypothesized to promote epileptogenesis. Although physical training (PT) was reported to cause further increase in neurogenesis after SE, how PT affect their integration pattern is still elusive, whether they integrate into normal circuits or increase aberrant integrations is yet to be determined. To understand this basic mechanism by which PT effects SE and to elaborate the possible role of neuronal integrations in prognosis of SE, we evaluated the effect of 4 weeks of treadmill PT in adult male mice after pilocarpine-induced SE on behavioral and aberrant integrations' parameters. Changes in BDNF gene methylation and its protein level in hippocampus was also measured at latent stage (2-weeks) to explore underlying pathways involved in increasing neurogenesis. Our results demonstrated that although PT increased proliferation and maturation of neurons in dentate gyrus, they showed reduced aberrant integrations into hippocampal circuitry assessed through a decrease in the number of ectopic granular cells, hilar basal dendrites and mossy fiber sprouting as compared to non-exercised SE mice. While SE decreased the percentage methylation of specific CpGs of BDNF gene's promoter, PT did not yield any significant difference in methylation of BDNF CpGs as compared to non-exercised SE mice. In conclusion, PT increases hippocampal neurogenesis through increasing BDNF levels by some pathways other than demethylating BDNF CpGs and causes post SE newly-born neurons to integrate into normal circuits thus resulting in decreased spontaneous recurrent seizures and enhanced spatial memory.


Asunto(s)
Giro Dentado/metabolismo , Hipocampo/metabolismo , Neurogénesis/fisiología , Condicionamiento Físico Animal , Estado Epiléptico/terapia , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Proliferación Celular/fisiología , Islas de CpG , ADN/metabolismo , Metilación de ADN , Giro Dentado/patología , Hipocampo/patología , Masculino , Ratones , Neuronas/metabolismo , Neuronas/patología , Pilocarpina , Estado Epiléptico/inducido químicamente , Estado Epiléptico/metabolismo , Regulación hacia Arriba
4.
J Chem Neuroanat ; 132: 102325, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37595695

RESUMEN

Anesthetics-induced disruption of dentate neurogenesis in the young brain is strongly suggested to contribute to delayed neurocognitive deficit. In postnatal rodents, the neurogenesis of the dentate gyrus (DG) is sequentially derived from the secondary dentate matrix, tertiary dentate matrix and subgranular zone (SGZ). However, the effects of anesthetics on the dentate neurogenesis derived from specific sites are poorly understood. To trace the new cells generated from the postnatal secondary dentate matrix, peak stage of the tertiary dentate matrix and early stage of the SGZ after isoflurane exposure, mice at postnatal day 1 (P1), P7 and P31 were injected with BrdU at 12 h before the exposure. We found that isoflurane exposure significantly reduced the numbers of proliferating cells (1 day old), immature granule cells (21 days old) or mature granule cells (42 days old) derived from the peak stage of the tertiary dentate matrix and postnatal secondary dentate matrix, but not from the SGZ. Quantitative assessment of BrdU-/BrdU+NeuN-positive cells and cleaved caspase-3 level in the DG indicated that the reduction was correlated with cell loss rather than neuronal differentiation. Mechanistically, we demonstrated that the PI3K/Akt/GSK-3ß pathway enriched by mRNA-sequencing is a requirement for the isoflurane-induced loss of 1-day-old proliferating cells generated from the tertiary dentate matrix. In addition, this study demonstrated that P1 and P7 mice, but not P31 mice exposure to isoflurane resulted in subsequent deficits in performance of the tasks of the Morris Water Maze.


Asunto(s)
Isoflurano , Animales , Ratones , Isoflurano/farmacología , Bromodesoxiuridina , Glucógeno Sintasa Quinasa 3 beta , Fosfatidilinositol 3-Quinasas , Neurogénesis
5.
Acta Neurobiol Exp (Wars) ; 82(1): 96-105, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35451427

RESUMEN

Studies on rodents and nonhuman primates suggest that exposure to anesthetics, particularly in the young brain, is associated with neuronal apoptosis as well as hippocampal­dependent cognitive dysfunction. Disruption of the development of dentate gyrus may play an important role in anesthetics­induced neurotoxicity. However, the anesthetics triggered molecular events in the dentate gyrus of the developing brain are poorly understood. By integrating two independent data sets obtained from miRNA­seq and mRNA­seq respectively, this study aims to profile the network of miRNA and potential target genes, as well as relevant events occurring in the dentate gyrus of isoflurane exposed 7­day­old mice. We found that a single four hours exposure to isoflurane yielded 1059 pairs of differently expressed miRNAs/target genes in the dentate gyrus. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis further indicates that dysregulated miRNAs/target genes have far­reaching effects on the cellular pathophysiological events, such as cell apoptosis, axon development, and synaptic transmission. Our results would greatly broaden our functional understanding of the role of miRNA/target gene in the context of anesthetics­induced neurotoxicity.


Asunto(s)
Anestésicos , Isoflurano , MicroARNs , Anestésicos/farmacología , Animales , Giro Dentado , Hipocampo , Isoflurano/toxicidad , Ratones , MicroARNs/genética
6.
Exp Neurol ; 347: 113918, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34748756

RESUMEN

In temporal lobe epilepsy (TLE), abnormal axon guidance and synapse formation lead to sprouting of mossy fibers in the hippocampus, which is one of the most consistent pathological findings in patients and animal models with TLE. Glypican 4 (Gpc4) belongs to the heparan sulfate proteoglycan family, which play an important role in axon guidance and excitatory synapse formation. However, the role of Gpc4 in the development of mossy fibers sprouting (MFS) and its underlying mechanism remain unknown. Using a pilocarpine-induced mice model of epilepsy, we showed that Gpc4 expression was significantly increased in the stratum granulosum of the dentate gyrus at 1 week after status epilepticus (SE). Using Gpc4 overexpression or Gpc4 shRNA lentivirus to regulate the Gpc4 level in the dentate gyrus, increased or decreased levels of netrin-1, SynI, PSD-95, and Timm score were observed in the dentate gyrus, indicating a crucial role of Gpc4 in modulating the development of functional MFS. The observed effects of Gpc4 on MFS were significantly antagonized when mice were treated with L-leucine or rapamycin, an agonist or antagonist of the mammalian target of rapamycin (mTOR) signal, respectively, demonstrating that mTOR pathway is an essential requirement for Gpc4-regulated MFS. Additionally, the attenuated spontaneous recurrent seizures (SRSs) were observed during chronic stage of the disease by suppressing the Gpc4 expression after SE. Altogether, our findings demonstrate a novel control of neuronal Gpc4 on the development of MFS through the mTOR pathway after pilocarpine-induced SE. Our results also strongly suggest that Gpc4 may serve as a promising target for antiepileptic studies.


Asunto(s)
Glipicanos/biosíntesis , Fibras Musgosas del Hipocampo/metabolismo , Pilocarpina/toxicidad , Transducción de Señal/fisiología , Estado Epiléptico/metabolismo , Serina-Treonina Quinasas TOR/biosíntesis , Animales , Células Cultivadas , Glipicanos/antagonistas & inhibidores , Masculino , Ratones , Fibras Musgosas del Hipocampo/efectos de los fármacos , Agonistas Muscarínicos/toxicidad , Transducción de Señal/efectos de los fármacos , Estado Epiléptico/inducido químicamente , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
7.
Brain Behav ; 11(1): e01949, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33201600

RESUMEN

INTRODUCTION: Recent animal studies showed that isoflurane exposure may lead to the disturbance of hippocampal neurogenesis and later cognitive impairment. However, much less is known about the effect of isoflurane exposure on the neurons generated form tertiary dentate matrix, even though a great increase of granule cell population during the infantile period is principally derived from this area. METHODS: To label the new cells originated from the tertiary dentate matrix, the mice were injected with BrdU on postnatal day 6 (P6). Then, the mice were exposed to isoflurane for 4 hr at 1, 8, 21, and 42 days after BrdU injection, and the brains were collected 24 hr later. The loss of newly generated cells/neurons with different developmental stage was assessed by BrdU, BrdU + DCX, BrdU + NeuN, or BrdU + Prox-1 staining, respectively. RESULTS: We found that the isoflurane exposure significantly decreased the numbers of nascent cells (1 day old) and mature neurons (42 days old), but had no effect on the immature (8 days old) and early mature neurons (8 and 21 days old, respectively). CONCLUSION: The results suggested isoflurane exposure exerts the neurotoxic effects on the tertiary dentate matrix-originated cells with an age-defined pattern in mice, which partly explain the cognitive impairment resulting from isoflurane exposure to the young brain.


Asunto(s)
Isoflurano , Animales , Proliferación Celular , Giro Dentado , Proteína Doblecortina , Hipocampo , Isoflurano/toxicidad , Ratones , Neurogénesis , Neuronas
8.
Stem Cell Res ; 49: 102102, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33279798

RESUMEN

In animal models with temporal lobe epilepsy (TLE), the status epilepticus (SE) leads to a dramatic increase in number of newly born neuron in the subgranular zone (SGZ) of dentate gyrus. How the SE confers a modulation in the dentate neurogenesis is mostly unknown. Gadd45b is involved in epigenetic gene activation by DNA demethylation. This study was performed to present a novel mechanism underling SE-induced dentate neurogenesis. A transient induction (12 hrs to 3 days) of Gadd45b was observed in dentate gyrus of mice after pilocarpine-induced SE. Labeling the dividing cells with BrdU, we next found that the induction of Gadd45b was required to increase the rate of cell proliferation in the dentate gyrus at 7 and 14 days after SE. Afterward, the DNA methylation levels for candidate growth factor genes critical for the adult neurogenesis were assayed with Sequenom MassARRAY Analyzer. The results indicated that Gadd45b was necessary for SE-induced DNA demethylation of specific promoters and expression of corresponding genes in the dentate gyrus, including brain-derived neurotrophic factor (BDNF) and fibroblast growth factor-2 (FGF-2). Using Timm staining, we further suggested that SE-induced Gadd45b might contribute to the subsequent mossy fiber sprouting (MFS) in the chronically epileptic hippocampus via epigenetic regulation of dentate neurogenesis at early stage after SE. Together, Gadd45b links pilocarpine-induced SE to epigenetic DNA modification of secreted factors in the dentate gyrus, leading to extrinsic modulation on the neurogenesis.


Asunto(s)
Giro Dentado , Estado Epiléptico , Animales , Antígenos de Diferenciación , Epigénesis Genética , Hipocampo , Ratones , Neurogénesis , Pilocarpina/toxicidad , Estado Epiléptico/inducido químicamente , Estado Epiléptico/genética
9.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 33(2): 99-102, 2008 Feb.
Artículo en Zh | MEDLINE | ID: mdl-18326902

RESUMEN

OBJECTIVE: To prove the existence neurons in the rat corpus callosum, the potential function of these neurons and their connection. METHODS: Immunohistochemistry was used performed to examine the expressions of NeuN, a mature neuron marker,and N-type voltage-dependent valcium channel alpha1-subunit (Cav2.2)in the section of the rat corpus callosum. Horseradish peroxidase (HRP) normal sodium solution (30%), the retrograde tracer,was injected under the frontal forceps of corpus callousm and HRP absorbed by the process of neurons in the brain slices was stained with tetramethyl benzidine. RESULTS: There were some NeuN positive cells in the rat corpus callosum and Cav2.2 was detected in some of these NeuN positive cells.Neurons with positive HRP were found in the rat corpus callosum and some of these neurons connected to the cortex or corpus striatum. CONCLUSION: There are a few neurons in the corpus callosum of adult rats and some of them express Cav2.2. Neurons in the corpus callosum have connections with the brain cortex or corpora striatum.


Asunto(s)
Canales de Calcio Tipo N/biosíntesis , Cuerpo Calloso/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Neuronas/citología , Proteínas Nucleares/biosíntesis , Animales , Cuerpo Calloso/citología , Proteínas de Unión al ADN , Masculino , Vías Nerviosas/fisiología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
10.
Artículo en Inglés | WPRIM | ID: wpr-981599

RESUMEN

Background In mainland China, patients with neovascular age-related macular degeneration (nAMD) have approximately an 40% prevalence of polypoidal choroidal vasculopathy (PCV). This disease leads to recurrent retinal pigment epithelium detachment (PED), extensive subretinal or vitreous hemorrhages, and severe vision loss. China has introduced various treatment modalities in the past years and gained comprehensive experience in treating PCV.Methods A total of 14 retinal specialists nationwide with expertise in PCV were empaneled to prioritize six questions and address their corresponding outcomes, regarding opinions on inactive PCV, choices of anti-vascular endothelial growth factor (anti-VEGF) monotherapy, photodynamic therapy (PDT) monotherapy or combined therapy, patients with persistent subretinal fluid (SRF) or intraretinal fluid (IRF) after loading dose anti-VEGF, and patients with massive subretinal hemorrhage. An evidence synthesis team conducted systematic reviews, which informed the recommendations that address these questions. This guideline used the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach to assess the certainty of evidence and grade the strengths of recommendations. Results The panel proposed the following six conditional recommendations regarding treatment choices. (1) For patients with inactive PCV, we suggest observation over treatment. (2) For treatment-na?ve PCV patients, we suggest either anti-VEGF monotherapy or combined anti-VEGF and PDT rather than PDT monotherapy. (3) For patients with PCV who plan to initiate combined anti-VEGF and PDT treatment, we suggest later/rescue PDT over initiate PDT. (4) For PCV patients who plan to initiate anti-VEGF monotherapy, we suggest the treat and extend (T&E) regimen rather than the pro re nata (PRN) regimen following three monthly loading doses. (5) For patients with persistent SRF or IRF on optical coherence tomography (OCT) after three monthly anti-VEGF treatments, we suggest proceeding with anti-VEGF treatment rather than observation. (6) For PCV patients with massive subretinal hemorrhage (equal to or more than four optic disc areas) involving the central macula, we suggest surgery (vitrectomy in combination with tissue-plasminogen activator (tPA) intraocular injection and gas tamponade) rather than anti-VEGF monotherapy. Conclusions Six evidence-based recommendations support optimal care for PCV patients' management.

11.
Biomed Environ Sci ; 20(3): 198-202, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17672209

RESUMEN

OBJECTIVE: To study the possible effect of tetracycline on protease-resistant activity in vitro and infectivity in vivo of a scrapie strain 263K. METHODS: Scrapie pathogens were incubated with tetracycline at different concentrations for various periods of time and protease-resistant PrP signals were evaluated with proteinase K-treatment and Western blots. The preparations treated with tetracycline were intracerebrally inoculated into golden hamsters and typical TSE manifestations were noted. PrPSc in brain tissues of the infected animals was detected by PrP specific Western blot assays. RESULTS: Protease-resistant PrP was significantly reduced in or removed from the preparations treated with tetracycline in a dose-dependant manner. Compared with the control group after incubated for 53.75 +/- 0.50 days, the preparations treated with 5 mmol/L and 20 mmol/L tetracycline prolonged the incubation time of 61.5 +/- 1.73 and 59.5 +/- 0.58 days (P < 0.05). CONCLUSION: Treatment of scrapie pathogen 263K with tetracycline reduces or removes its protease-resistant activity in vitro.


Asunto(s)
Péptido Hidrolasas/metabolismo , Proteínas PrPSc/metabolismo , Proteínas PrPSc/patogenicidad , Scrapie/patología , Tetraciclina/farmacología , Animales , Encéfalo/patología , Cricetinae , Factores de Tiempo
12.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(3): 396-400, 2007 Jun.
Artículo en Zh | MEDLINE | ID: mdl-17611313

RESUMEN

OBJECTIVE: To observe the effect of ligustrazine on cell proliferation in subventricular zone (SVZ) in rat brain with focal cerebral ischemia reperfusion injury. METHODS: Male SD rats were randomly divided into a normal group,a sham operation group,a ligustrazine treatment group, and a control group. The ligustrazine treatment group and the control group were further divided into 5 subgroups: 1d, 3d, 7d, 14d, and 21d reperfusion after 2h middle cerebral artery occlusion (MCAO). The focal cerebral ischemia-reperfusion model was made by MCAO. S phase cells were labelled with BrdU. Immunohistochemistry method was conducted to detect the BrdU positive cells. The total number of BrdU positive cells in the SVZ was measured. The expression of neuro nitric oxide synthase (nNOS) was detected with Western blot method. RESULTS: There was a significant increase of BrdU positive cells in SVZ of ligustrazine treatment in the 1d and 3d group compared with that of the control group (P<0.01). The total number of BrdU positive cells reached a peak in 7d group and declined afterwards. Cells proliferated also in SVZ on the contralateral side, and peaked at 7d. The nNOS expression of ligustrazine administration after the focal cerebral ischemia-reperfusion decreased at 1d and 3d after the reperfusion compared with that of the control group (P<0.05), and increased at 7d, but with no significant difference compared with that of the control group. CONCLUSION: Ligustrazine may promote the cell proliferation in SVZ of adult rats with ischemia-reperfusion injury by decreasing the nNOS expression.


Asunto(s)
Isquemia Encefálica/fisiopatología , Proliferación Celular/efectos de los fármacos , Ventrículos Cerebrales/patología , Pirazinas/farmacología , Daño por Reperfusión/fisiopatología , Animales , Western Blotting , Ventrículos Cerebrales/metabolismo , Infarto de la Arteria Cerebral Media/fisiopatología , Masculino , Óxido Nítrico Sintasa de Tipo I/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
13.
Biomed Environ Sci ; 18(4): 273-80, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16274110

RESUMEN

OBJECTIVE: To prepare the PrP specific monoclonal antibodies (mAbs) that can be used for the detection of mammalian prions and study of pathogenesis of prion diseases. METHODS: Several BALB/c mice were immunized with recombinant hamster prion protein (HaPrP). Three hybridoma cell lines designated as B7, B9, and B10, secreting monoclonal antibodies against HaPrP, were established by hybridoma technique. The mAbs reactivities were evaluated with ELISA, Western blot, and immunohistochemistry. RESULTS: The mAbs produced by these cell lines reacted well with different recombinant hamster PrP proteins. Western blot analyses showed that mAbs B7 and B9 reacted with PrPSc from the scrapie-infected animals after proteinase K digestion with three glycosylated forms. The mAbs exhibited cross-reactivity with various PrPC from several other mammalian species, including humans and cattles. Immunohistochemistry assays confirmed that mAbs B7 and B9 could recognize not only extracellular but also intracellular PrPsSc. CONCLUSION: The mAbs of prion protein are successfully generated by hybridoma technique and can be applied for the diagnosis of prion associated diseases.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Proteínas PrPC/inmunología , Proteínas PrPSc/inmunología , Animales , Western Blotting , Encéfalo/metabolismo , Línea Celular Tumoral , Cricetinae , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunización , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Proteínas PrPC/genética , Proteínas PrPSc/genética , Proteínas Recombinantes/inmunología
14.
Exp Neurol ; 273: 273-87, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26384773

RESUMEN

Emerging evidence has linked chronic temporal lobe epilepsy to dramatically reduced neurogenesis in the dentate gyrus. However, the profile of different components of neurogenesis in the chronically epileptic hippocampus is still unclear, especially the incorporation of newly generated cells. To address the issue, newly generated cells in the sub-granular zone of the dentate gyrus were labeled by the proliferation marker bromodeoxyuridine (BrdU) or retroviral vector expressing green fluorescent protein 2 months after pilocarpine-induced status epilepticus. The newly generated neurons that extended axons to CA3 area or integrated into memory circuits were visualized by cholera toxin B subunit retrograde tracing, and detecting activation of BrdU(+) cells following a recall of spatial memory test at the chronic stage of TLE. We found that the microenvironment was still able to sustain significant neuronal differentiation of newly generated cells at 2 months post-status epilepticus time-point, and newly added neurons into granular cell layer were still able to integrate into neuronal circuitry, both anatomically and functionally. Quantified analyses of BrdU(+) or Ki-67(+) cells demonstrated that there was a reduced proliferation of progenitor cells and diminished survival of newly generated cells in the epileptic hippocampus. Both decreased levels of neurotrophic factors in the surrounding milieu and cell loss in the CA3 area might contribute the decreased production of new cells and their survival following chronic epilepsy. These results suggest that decreased neurogenesis in the chronically epileptic hippocampus 2 months post status epilepticus is not associated with altered integration of newly generated neurons, and that developing strategies to augment hippocampal neurogenesis in chronic epilepsy might be protective.


Asunto(s)
Hipocampo/patología , Hipocampo/fisiopatología , Vías Nerviosas/fisiología , Neurogénesis/fisiología , Neuronas/fisiología , Estado Epiléptico/patología , Animales , Diferenciación Celular , Movimiento Celular , Toxina del Cólera/metabolismo , Modelos Animales de Enfermedad , Femenino , Estudios de Seguimiento , Ratones , Ratones Endogámicos , Agonistas Muscarínicos , Red Nerviosa/fisiología , Proteínas del Tejido Nervioso/metabolismo , Pilocarpina/toxicidad , Retroviridae/genética , Estado Epiléptico/inducido químicamente , Células Madre , Factores de Tiempo , Transducción Genética
15.
Biomed Environ Sci ; 17(1): 8-20, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15202859

RESUMEN

OBJECTIVE: To expatiate dynamic changes in hamsters infected with scrapie strain 263K, to observe the presence and aggravation of various forms of PrP and PrP(Sc) during incubation period, and to probe primarily the relationship between the onset of clinic manifestations and the presence of different PrP(Sc) forms. METHODS: Hamster-adapted scrapie strain 263K was intracerebrally inoculated into hamsters. Different forms of PrP and PrP(Sc) were monitored dynamically by Western blot and immuno-histochemical assays. The presence of scrapie-associated fibril (SAF) was assayed by electron microscopy analysis (EM) and immuno-golden EM. RESULTS: PrP(Sc) was initially detected in the brain tissues of the animals in 20 days post-inoculation by immunohistochemistry and 40 days with Western blot. Quantitative evaluations revealed that the amounts of PrP and PrP(Sc) in brain tissues increased along with the incubation. Several high and low molecular masses of PrP were seen in the brains of the long-life span infected animals. Deglycosylation assays identified that the truncated PrP in the infected brains showed similar glycosylation patterns as the full-length PrP. The presence of short fragments was seemed to relate with the onset of clinical conditions. CONCLUSION: These results indicate that infectious agents exist and accumulate in central nerve system prior to the onset of the illness. Various molecular patterns of PrP(Sc) may indwell in brain tissues during the infection.


Asunto(s)
Encéfalo/metabolismo , Proteínas PrPC/análisis , Proteínas PrPSc/análisis , Scrapie/metabolismo , Animales , Western Blotting , Encéfalo/ultraestructura , Cricetinae , Modelos Animales de Enfermedad , Femenino , Glicosilación , Inmunohistoquímica , Mesocricetus , Microscopía Electrónica , Proteína PrP 27-30/análisis , Proteína PrP 27-30/metabolismo , Proteínas PrPC/metabolismo , Proteínas PrPSc/metabolismo , Scrapie/patología
16.
Biomed Environ Sci ; 17(1): 65-78, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15202866

RESUMEN

OBJECTIVE: To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.c.), intraperitoneal (i.p.), intragastrical (i.g.), intracardiac and intramuscular (i.m.) approaches. METHODS: Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrP(Sc) deposits, and patterns of PK-resistant PrP were analyzed by HE stain, immnunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) specific IHC. RESULTS: The animals inoculated in i.m. and i.p. ways with crude PrP(Sc) extracts showed clinical signs at the average incubation of 69.2 +/- 2.8 and 65.5 +/- 3.9 days. Inoculation in i.c. and intracardiac ways with fine PrP(Sc) extracts (0.00035 g) caused similar, but relative long incubation of around 90 days. Only one out of eight hamsters challenged in i.g. way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4) with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrP(Sc) deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. CONCLUSION: Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrP(Sc). The neuropathological changes and PrP(Sc) deposits seem to be related with regions and inoculating pathways.


Asunto(s)
Encéfalo/patología , Priones , Scrapie/patología , Administración Oral , Animales , Western Blotting , Encéfalo/metabolismo , Cricetinae , Gliosis/metabolismo , Gliosis/patología , Inmunohistoquímica , Inyecciones Intramusculares , Inyecciones Intraperitoneales , Inyecciones Intraventriculares , Neuronas/enzimología , Neuronas/patología , Fosfopiruvato Hidratasa/metabolismo , Priones/administración & dosificación , Priones/metabolismo , Priones/patogenicidad , Scrapie/metabolismo
17.
Brain Res ; 1493: 1-12, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23165119

RESUMEN

Metabotropic glutamate receptor 5 (mGluR5) is involved in neural stem cell self-renewal, proliferation, differentiation and survival. In this study, we aimed to further determine the role of mGluR5 in the development of hippocampus using mGluR5 deficit (mGluR5(-/-)) and wild type (mGluR5(+/+)) mice at different developmental ages. We showed that the number of BrdU, NeuroD and DCX immunopositive cells was reduced significantly in mGluR5(-/-) than in mGluR5(+/+) mice from postnatal 7 days (P7) to P28, but not at P60. The length and intensity of DCX immunopositive apical dendrites in the dentate gyrus of mGluR5(-/-) mice were much shorter and lower than in mGluR5(+/+) mice respectively at P14, P21 and P28. NeuN immunostaining indicated an accelerated maturation of hippocampal neurons in mGluR5(-/-) mice. When mGluR5(+/+) mice were treated with 2-methyl-6-(phenylethynyl) pyridine (MPEP), a selective antagonist of mGluR5, decreased proliferation of progenitor cells was observed in the hippocampus at early postnatal developmental stages. At P14, there were more BrdU(+) cells in the stratum granulosum and subgranular layer of the dentate gyrus in mGluR5(+/+) than in mGluR5(-/-) mice, but the percentage of BrdU(+)+NeuroD(+)/BrdU(+) in the dentate gyrus did not change significantly between the two genotypes of mice. Western Blot study suggested that programmed neuronal death was p53-dependent apoptosis in the developmental hippocampus in mGluR5(+/+) mice.


Asunto(s)
Hipocampo/citología , Hipocampo/crecimiento & desarrollo , Células-Madre Neurales/citología , Neurogénesis/fisiología , Neuronas/citología , Receptores de Glutamato Metabotrópico/fisiología , Animales , Apoptosis/fisiología , Diferenciación Celular/fisiología , Proliferación Celular , Dendritas/fisiología , Proteína Doblecortina , Antagonistas de Aminoácidos Excitadores/farmacología , Femenino , Genotipo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células-Madre Neurales/fisiología , Neuronas/fisiología , Piridinas/farmacología , Receptor del Glutamato Metabotropico 5 , Receptores de Glutamato Metabotrópico/antagonistas & inhibidores , Receptores de Glutamato Metabotrópico/genética
19.
Chinese Medical Journal ; (24): 2610-2616, 2016.
Artículo en Inglés | WPRIM | ID: wpr-230913

RESUMEN

<p><b>BACKGROUND</b>Polypoidal choroidal vasculopathy (PCV) is characterized by the presence of polyps with or without a branching vascular network and more prevalent among Asians. The aim of this study was to compare the outcomes of conbercept therapy between two different angiographic subtypes of PCV.</p><p><b>METHODS</b>Fifty-eight patients of PCV were classified into two phenotypes according to indocyanine green angiography (ICGA). In Type 1, both feeder and draining vessels are visible on ICGA and network vessels are numerous. In Type 2, neither feeder nor draining vessels are detectable, and the number of network vessels is small. The patients were treated with intravitreal conbercept (IVC) for 3 months. Additional IVC was given at subsequent monthly visits, if needed. The patients were followed up for 12 months, and changes in mean best-corrected visual acuity (BCVA), central retinal thickness (CRT), subretinal fluid (SRF) thickness, pigmented epithelial detachment (PED), hemorrhage, and number of polypoidal lesions were evaluated.</p><p><b>RESULTS</b>The mean BCVA in Type 2 PCV (15.92 ± 9.76 letters) achieved a significantly greater improvement than that in the Type 1 (14.10 ± 9.07 letters) at month 12 (t = 2.37, P< 0.01). Moreover, the mean CRT decrease was numerically greater in Type 2 (120.44 ± 73.81 μm) compared with Type 1 (106.48 ± 72.33 μm) at month 6 (t = 4.31, P< 0.01), and greater in Type 2 (130.21 ± 76.28 μm) compared with Type 1 (111.67 ± 79.57 μm) at month 9 (t = 1.87, P< 0.01). There was no significant difference between the two types for the decrease in SRF thickness, PED height, and regression of polyps from month 3 to 12 (t = 2.97, P > 0.05).</p><p><b>CONCLUSION</b>Classification systems for PCV will show differences in presentation, natural history, or response to anti-vascular endothelial growth factor treatment and might, therefore, provide a new key to the choice of treatment for the disease.</p>


Asunto(s)
Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Coroides , Cirugía General , Neovascularización Coroidal , Cirugía General , Cuidados Posoperatorios , Estudios Retrospectivos , Resultado del Tratamiento , Agudeza Visual , Fisiología
20.
Artículo en Inglés | WPRIM | ID: wpr-277958

RESUMEN

Objective To evaluate the application of a mobile platform-based system in the management of fundus disease in outpatient settings. Methods In the outpatient departments of fundus disease,premature babies requiring eye examination under general anesthesia and adults requiring intraocular surgery were enrolled as the subjects. According to the existing clinical practices,we developed a system that met the requirements of clinical practices and optimized the clinical management. Based on the FileMaker database,the tablet computers were used as the mobile platform and the system could also be run in iPad and PC terminals.Results Since 2013,the system recorded 7500 cases of special examinations. Since July 2015,4100 cases of intravitreal drug injection were also recored in the system. Multiple-point and real-time reservation pattern increased the efficiency and opimize the clinical management. All the clinical data were digitalized. Conclusion The mobile platform-based system can increase the efficacy of examination and other clinical processes and standardize data collection;thus,it is feasible for the clinical practices in outpatient departments of ophthalmology.


Asunto(s)
Adulto , Humanos , Recién Nacido , Computadoras de Mano , Manejo de la Enfermedad , Recien Nacido Prematuro , Pacientes Ambulatorios , Enfermedades de la Retina , Terapéutica
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA