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2.
J. optom. (Internet) ; 16(1)January - March 2023. tab, graf
Artigo em Inglês | IBECS | ID: ibc-214433

RESUMO

Purpose: To corroborate whether vessels on the surface of the optic nerve head can provide protection against the loss of underlying axons in subjects with manifest glaucoma.MethodsIn this pilot study, thirty-six glaucomatous eyes with a perimetric defect in the Bjerrum area were included. The retinal nerve fiber layer (RNFL) thickness was measured in each of the sectors of the clock-hour map obtained by Cirrus HD-OCT considering the presence or absence of blood vessels. These sectors were related with their corresponding areas of the retina examined in the visual field using a mathematical model of the retina introduced by Jansonius, in order to determine the values of threshold sensitivity in those areas in the presence or absence of vessels.ResultsWe corroborated the protective role of the blood vessel for peripapillary RNFL thickness of clock-hour 12 despite obtaining a p-value (p = 0.023; w = 228.5) close to the acceptance zone (p ≥ 0.05). The mean ± standard deviation with vessel and without vessel were 70.95 ± 24.35 and 88.46 ± 23.96, respectively. No differences were found between the mean values of threshold sensitivity to the presence or absence of blood vessels in each of the sectors considered.ConclusionsOur findings do not allow us to affirm that there is an association between the presence of a vessel and protection against glaucomatous damage in subjects with an advanced manifestation of the disease. In the future, more extensive studies are needed to study this relationship in subjects with early glaucoma. (AU)


Assuntos
Humanos , Retina , Glaucoma , Fibras Nervosas , Disco Óptico , Projetos Piloto , Astrócitos , Glaucoma de Ângulo Aberto , Campos Visuais , Humor Aquoso , Vasos Sanguíneos
3.
Neurología (Barc., Ed. impr.) ; 35(6): 400-408, jul.-ago. 2020. graf
Artigo em Espanhol | IBECS | ID: ibc-197792

RESUMO

INTRODUCCIÓN: La esclerosis múltiple (EM) es una enfermedad autoinmune desmielinizante del sistema nervioso central (SNC) en la que los astrocitos tienen una participación importante como células inmunes del SNC, aunque su actividad como células presentadoras de antígeno (APC) aún es discutida. DESARROLLO: En la presente revisión se analiza la evidencia existente sobre la participación de los astrocitos en la inflamación del SNC en la EM, así como diversos mecanismos que modifican su actividad en la enfermedad. CONCLUSIONES: Los astrocitos desempeñan un papel trascendental en la patogénesis de la EM, debido a que expresan receptores TLR, así como proteínas del complejo principal de histocompatibilidad (MHC) clase I y II. Además, participan en la regulación de la barrera hematoencefálica (BHE) y la modulación de la actividad de los linfocitos T mediante la producción de citocinas. Futuros estudios deberán enfocarse en el papel de los astrocitos con el objetivo de encontrar nuevos blancos terapéuticos para el tratamiento de la EM


INTRODUCTION: Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system (CNS), in which astrocytes play an important role as CNS immune cells. However, the activity of astrocytes as antigen-presenting cells (APC) continues to be subject to debate. DEVELOPMENT: This review analyses the existing evidence on the participation of astrocytes in CNS inflammation in MS and on several mechanisms that modify astrocyte activity in the disease. CONCLUSIONS: Astrocytes play a crucial role in the pathogenesis of MS because they express toll-like receptors (TLR) and major histocompatibility complex (MHC) class I and II. In addition, astrocytes participate in regulating the blood-brain barrier (BBB) and in modulating T cell activity through the production of cytokines. Future studies should focus on the role of astrocytes in order to find new therapeutic targets for the treatment of MS


Assuntos
Humanos , Esclerose Múltipla/etiologia , Esclerose Múltipla/patologia , Astrócitos/patologia , Inflamação/fisiopatologia
4.
Arch. Soc. Esp. Oftalmol ; 94(9): 449-452, sept. 2019. ilus
Artigo em Espanhol | IBECS | ID: ibc-186225

RESUMO

Introducción: El hamartoma astrocítico retiniano es un tumor benigno generalmente asintomático, asociado o no al complejo de esclerosis tuberosa. La hemorragia vítrea es una rara presentación. Caso clínico: Paciente de 12 años acude por visión de "una mancha negra" en el hemicampo temporal superior del ojo derecho. Refiere un episodio similar hace 2 años. En lámpara de hendidura el polo anterior es normal. En la funduscopia se evidencia una masa de aspecto translúcido blanco-amarillenta peripapilar y hemorragia vítrea peripapilar. Las características de la autofluorescencia, angiografía fluoresceínica y la tomografía de coherencia óptica son compatibles con un hamartoma astrocítico retiniano. Los estudios complementarios (serología y radiografías) y examen clínico completo descartan afectación sistémica asociada. Se procedió a un seguimiento estrecho del paciente hasta reabsorción de la hemorragía vítrea. Conclusión: La hemorragia vítrea es una rara complicación de hamartoma astrocítico retiniano y dificulta la exploración fundoscópica. Debería descartarse afectación sistémica


Introduction: Retinal astrocytic hamartoma is generally an asymptomatic benign tumour that may or may not be associated with the tuberous sclerosis complex. Haemorrhage is a rare presentation. Case report: The case concerns a 12-year-old patient with "a black spot" vision in the upper temporal hemifield of the right eye, who referred a similar episode 2 years ago. The anterior pole was normal in the slit lamp. A mass of translucent white-yellow peri-papillary appearance and vitreous peri-papillary haemorrhage was observed in funduscopy. The autofluorescence, fluorescence angiography, and optical coherence tomography characteristics were all compatible with retinal astrocytic hamartoma. Complementary studies (serology and X-rays) and the complete clinical examination rule out associated systemic involvement. The patient was followed-up closely until the vitreous haemorrhage was reabsorbed. Conclusion: Vitreous haemorrhage is a rare complication of Retinal astrocytic hamartoma and funduscopic exploration is difficult. Systemic involvement should be ruled out


Assuntos
Humanos , Criança , Hamartoma/diagnóstico , Doenças Retinianas/diagnóstico , Hemorragia Vítrea/etiologia , Astrócitos/patologia , Angiofluoresceinografia , Hamartoma/patologia , Doenças Retinianas/patologia , Microscopia com Lâmpada de Fenda , Tomografia de Coerência Óptica
5.
Eur. j. anat ; 23(1): 27-40, ene. 2019. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-181628

RESUMO

An absence of the thyroid hormone during the critical period of brain development causes delayed maturation of glial cells and neurons and decreases the number of hippocampal cells. This study aims to examine the impact of maternal subclinical hypothyroidism (SCH) on pup hippocampus during the prepubertal and pubertal periods by means of assessing the histopathological changes in astrocytes and neurons.Twelve Wistar albino pregnant rats were divided into two groups, Group H and Group C. Group C was designated as the control group and nothing was added to their drinking water. SCH was induced in Group H by administering 6-propyl-2-thiouracil (PTU) at a final concentration of 0.01% in the drinking water of pregnant rats for 21 days. Male pups for each group were divided evenly and evaluated on either day 15 (prepubertal) or 60 (pubertal) (7 pups in each group). At the end of the experimental period, the rats were sacrificed for analysis of brain tissue. Immunoreactivity intensities of MAP-2 and GFAP were evaluated in hippocampus tissue. Thyroid function was determined using ELISA. The structure of hippocampus was evaluated by hematoxylin-eosin staining. Finally, the TUNEL method was utilized to show apoptosis of hippocampus tissue. The results were analyzed statistically.The findings show that maternal SCH causes disruption in hippocampal cytoskeleton and dendritic organization, especially during the pubertal period, as well as a decrease in MAP-2 expression. We observed structural deformation in astrocytes, reduced astrocyte survival and GFAP expression. Finally, we found that the number of neuronal apoptotic cells tended to increase in the pubertal period


No disponible


Assuntos
Animais , Feminino , Ratos , Astrócitos , Cérebro/química , Hipotireoidismo/metabolismo , Hipocampo/química , Proteína Glial Fibrilar Ácida/administração & dosagem , Hipocampo/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Prenhez , Tiouracila/administração & dosagem , Ensaio de Imunoadsorção Enzimática/veterinária , Citoesqueleto , Cérebro/crescimento & desenvolvimento , Hipotireoidismo/veterinária , Morfogênese/efeitos dos fármacos , Imuno-Histoquímica/veterinária
6.
J. physiol. biochem ; 74(4): 539-547, nov. 2018. tab, graf
Artigo em Inglês | IBECS | ID: ibc-179032

RESUMO

The link between obesity-induced systemic inflammation and decreased insulin signalling is well-known. It is also known that peripherally produced inflammatory cytokines can cross the blood-brain barrier, resulting in the release of neurotoxins that can ultimately lead to the demise of central nervous system integrity. A high-mesembrine Sceletium tortuosum extract was recently shown to possess cytoprotective and mild anti-inflammatory properties in monocytes and to target specific p450 enzymes to reduce adrenal glucocorticoid synthesis. This is significant since the aetiology of both obesity and diabetes is linked to inflammation and excess glucocorticoid production. Given the interlinked nature of glucocorticoid action and inflammation, central immunomodulatory effects of two Sceletium tortuosum extracts prepared by different extraction methods were investigated. Human astrocytes were pre-treated for 30 min, before exposure to Escherichia coli lipopolysaccharide for 23.5 h (in the presence of treatment). Cytotoxicity, mitotoxicity and cytokine responses (basally and in response to inflammatory stimulus) were assessed. In addition, total polyphenol content, antioxidant capacity and selected neural enzyme inhibition capacity were assessed for both extracts. The high-mesembrine Sceletium extract exerted cytoprotective and anti-inflammatory effects. In contrast, the high delta7-mesembrenone extract, rich in polyphenols, exhibited potent antioxidant effect, although with relatively higher risk of adverse effects with overdose. We conclude that both Sceletium tortuosum extracts may be employed as either a preventative supplement or complimentary treatment in the context of obesity and diabetes; however, current data also highlights the impact that extraction methods can have on plant product mechanism of action


Assuntos
Humanos , Anti-Inflamatórios não Esteroides/farmacologia , Astrócitos , Alcaloides Indólicos/farmacologia , Mesembryanthemum/química , Extratos Vegetais/farmacologia , Acetilcolinesterase/metabolismo , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/isolamento & purificação , Antioxidantes , Linhagem Celular , Inibidores da Colinesterase , Alcaloides Indólicos/análise , Alcaloides Indólicos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
7.
Arch. Soc. Esp. Oftalmol ; 92(3): 141-144, mar. 2017. ilus
Artigo em Espanhol | IBECS | ID: ibc-160965

RESUMO

INTRODUCCIÓN: La presunta proliferación circunscrita solitaria de los astrocitos retinianos (PPCSAR) es una pequeña lesión solitaria y definida. Caso clínico. Varón de 58 años con una lesión opaca amarillenta inferonasal al disco óptico. La angiofluoresceingrafía mostró hiperfluorescencia leve en fase precoz y tardía. La ecografía no mostró calcificación. La autofluorescencia presentó autofluorescencia moderada. La tomografía de coherencia óptica mostró la masa con una configuración de bola de nieve con superficie lisa. Más de un año después, la lesión se mantuvo sin cambios. DISCUSIÓN: PSCRAP es una lesión benigna estable. Es importante diferenciarla de otras lesiones retinianas blanco-amarillentas


INTRODUCTION: Presumed solitary circumscribed retinal astrocytic proliferation (PSCRAP) is a small defined solitary lesion. Case report. A 58-year-old man had an opaque yellow retinal lesion inferonasal to the optic disc. Fluorescein angiography showed mild early hyperfluorescence and late fluorescence. Ultrasound showed no calcification. Autofluorescence disclosed moderate hyperautofluorescence. Optical coherence tomography showed the mass with a snowball configuration and a smooth surface. More than one year later, the lesion was unchanged. DISCUSSION: PSCRAP is a benign stable lesion. The main importance lies in its differentiation from well-circumscribed yellow-white lesions of the retina


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Astrócitos , Astrocitoma/complicações , Astrocitoma , Hamartoma , Angiofluoresceinografia/instrumentação , Angiofluoresceinografia/métodos , Ultrassonografia/métodos , Angiografia/instrumentação , Angiografia/métodos , Angiografia , Diagnóstico Diferencial
8.
Rev. Soc. Esp. Dolor ; 23(4): 186-190, jul.-ago. 2016. tab
Artigo em Espanhol | IBECS | ID: ibc-154045

RESUMO

La neuromielitis óptica (NMO) o enfermedad de Devic es un trastorno autoinmune, inflamatorio y desmielinizante, que afecta principalmente al nervio óptico y la médula espinal. El cuadro clínico está caracterizado por dolor de tipo neuropático, patrón de pérdida de la visión y aparición de fenómenos visuales positivos, como fosfenos inducidos por movimiento. En lesiones activas se ha demostrado que hay amplificación del dolor, esencialmente por acción excitatoria por niveles excesivos de glutamato. En las lesiones establecidas, la pérdida de los astrocitos representa la generalidad del cuadro. El dolor en la enfermedad de Devic es más frecuente y grave que en la esclerosis múltiple, y tiene un grave impacto en la vida cotidiana. Hay literatura que refiere resultados aislados con carbamazepina. En este caso clínico, se ve claramente el efecto analgésico con disminución de los espasmos dolorosos de carbamazepina y neuromoduladores + opioides fuertes en combinación con psicoterapia para disminuir niveles de ansiedad y depresión y lograr un manejo integral del dolor (AU)


Neuromyelitis optica (NMO) or Devic’s disease is an autoimmune disorder, inflammatory and demyelinating, which mainly affects the optic nerve and spinal cord. The clinical is characterized by neuropathic pain type, pattern of vision loss and the appearance of positive visual phenomena as phosphenes induced movement. In active lesions it has been demonstrated that there is pain amplification excitatory action essentially by excessive levels of glutamate. In established injury, loss of astrocytes represents the generality of pain. Devic’s disease is more frequent and severe than in MS and has a serious impact on daily life. There literature refers isolated carbamazepine results. In this case report clearly shows the analgesic effect with decreased and painful spasms of neuromodulators + carbamazepine strong opioids in combination with psychotherapy to reduce levels of anxiety and depression and achieve a comprehensive pain management (AU)


Assuntos
Humanos , Feminino , Adulto , Neuromielite Óptica/complicações , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/psicologia , Manejo da Dor/métodos , Psicoterapia/métodos , Psicoterapia/tendências , Psicoterapia/instrumentação , Psicoterapia/organização & administração , Psicoterapia/normas , Astrócitos , Astrócitos/patologia , Qualidade de Vida , Carbamazepina/uso terapêutico , Receptores de Neurotransmissores/uso terapêutico , Analgésicos Opioides/uso terapêutico , Espasmo/complicações
9.
An. R. Acad. Farm ; 82(1): 51-67, ene.-mar. 2016. ilus
Artigo em Espanhol | IBECS | ID: ibc-152893

RESUMO

Todos los miembros de las familias de la neuroglía tienen la capacidad de adoptar un estado reactivo ('gliosis' de manera general; 'astrogliosis', 'oligodendrogliosis' y 'microgliosis', en su forma más específica) ante situaciones en que se modifica de manera importante la homeostasis del tejido nervioso y/o la dinámica funcional normal de las neuronas y sus células gliales acompañantes (traumas, intoxicaciones, infecciones, neurodegeneraciones). En este estado reactivo se convierten en 'nuevas células con nuevas funciones' pues cambian de manera importante sus funciones celulares con la expresión de nuevos genes. De esta forma pasan a ser actores principales en el escenario de las nuevas situaciones patológicas del Sistema Nervioso (SN). La activación de las células de neuroglia en principio es beneficiosa, tendente a solucionar los cambios patológicos, pero puede convertirse en perjudicial para el tejido nervioso. Asimismo, en los últimos años, se ha comprobado que también es causa de patología la falta de respuesta reactiva de las distintas células neuróglicas o la involución de estas células. Los estudios sobre estos diferentes tipos de células gliales reactivas han ampliado de manera muy importante los conocimientos que teníamos sobre la patogenia de las enfermedades del SN, y también nos están dando a conocer que pueden ser apoyos fundamentales para definir dianas farmacológicas terapéuticas o crear nuevas terapias celulares que ayuden a controlar el avance de las 'cascadas patogénicas' por la vía de activar la neuroprotección-neurorreparación y/o inhibir la neurotoxicidad-neurodegeneración


All members of the families of the neuroglia have the ability to adopt a reactive state ("gliosis" in general, "astrogliosis" "oligodendrogliosis" and "microgliosis" in its specific form) face to situations where importantly is modified homeostasis of the nervous tissue and / or normal functional dynamics of neurons and their accompanying neuroglial cells (trauma, neurotoxicity, infections, neurodegenerative processes). In this reactive state, neuroglial cells become 'new cells with new functions' because a significant change of their cellular functions occurs, mainly by the expression of new genes. Thus they become major players on the different stage of the new SN pathological situations. Activation of neuroglia cells is initially beneficial, aiming to solve the pathological changes, but it can turn detrimental to nerve tissue. Also, in recent years, it has been found that also the lack of reactive responses or the existence of "maladaptative responses" of the different neuroglial cells as well as the involution or regression of these cells, are important sources of nervous pathology. Studies of these different types of reactive glial cells have significantly expanded the knowledge we had about the pathogenesis of diseases of the SN. Moreover, many studies are revealing that they may be important to define new therapeutic drug targets or create new cell therapies to control the progress of the "pathogenic cascades", through activating neuroprotection-neurorepair and/or inhibiting the neurotoxicity-neurodegeneration


Assuntos
Humanos , Masculino , Feminino , Células Ependimogliais , Sistema Nervoso , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/epidemiologia , Neuroglia , Neuroglia/patologia , Sistema Nervoso/patologia , Tecido Nervoso , Tecido Nervoso/patologia , Gliose/complicações , Gliose/tratamento farmacológico , Gliose/fisiopatologia , Astrócitos , Oligodendroglia
10.
Neurología (Barc., Ed. impr.) ; 30(2): 119-129, mar. 2015. ilus
Artigo em Espanhol | IBECS | ID: ibc-134171

RESUMO

Introducción: Los astrocitos han sido considerados como células de sostén en el SNC. Sin embargo, hoy día se sabe que participan de forma activa en muchas de las funciones del SNC y que pueden tener un papel destacado en las enfermedades neurodegenerativas. Desarrollo: Se revisan las funciones del astrocito en el desarrollo y plasticidad del SNC, en el control sináptico, regulación del flujo sanguíneo, energía y metabolismo, en la barrera hematoencefálica, regulación de los ritmos circadianos, metabolismo lipídico y secreción de lipoproteínas y en la neurogénesis. Asimismo, se revisan sus marcadores y el papel de la astrogliosis. Conclusión: Los astrocitos tienen un papel activo en el SNC. Su conocimiento parece esencial para comprender los mecanismos de las enfermedades neurodegenerativas


Introduction: Astrocytes have been considered mere supporting cells in the CNS. However, we now know that astrocytes are actively involved in many of the functions of the CNS and may play an important role in neurodegenerative diseases. Development: This article reviews the roles astrocytes play in CNS development and plasticity; control of synaptic transmission; regulation of blood flow, energy, and metabolism; formation of the blood-brain barrier; regulation of the circadian rhythms, lipid metabolism and secretion of lipoproteins; and in neurogenesis. Astrocyte markers and the functions of astrogliosis are also described. Conclusion: Astrocytes play an active role in the CNS. A good knowledge of astrocytes is essential to understanding the mechanisms of neurodegenerative diseases


Assuntos
Humanos , Masculino , Feminino , Astrócitos/fisiologia , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/epidemiologia , Neuroglia/fisiologia , Proteína Glial Fibrilar Ácida/fisiologia , Sistema Nervoso Central/lesões , Sistema Nervoso Central/fisiologia , Sistema Nervoso Central/fisiopatologia
11.
An. R. Acad. Farm ; 81(1): 11-18, ene.-mar. 2015. ilus
Artigo em Espanhol | IBECS | ID: ibc-137391

RESUMO

Durante toda su vida, las neuronas están acompañadas por células neurogliales con las que establecen relaciones muy estrechas, tanto morfológicas como funcionales. Los resultados de su estudio en los últimos años han revolucionado los conceptos sobre la funcionalidad del SNC. Clásicamente se describen tres familias de células neurogliales en el SNC, astroglia, oligodendroglia y microglia. Mediante métodos morfológicos e inmunocitoquímicos se han descrito muchos tipos dentro de cada familia, incluyendo algunos de características novedosas, como las células NGR2+, con una gran variedad de efectos fisiológicos y patológicos sobre las neuronas y los circuitos neuronales. En la actualidad, estos elementos se consideran de primordial importancia en todas las teorías desarrolladas para explicar cualquier tipo de proceso fisiológico o patológico en el SNC ya que están implicadas tanto en la neuroprotección/neurorreparación como en la neurodegeneración. La comunicación celular glio-neuronal, neuro-glial y glio-glial, así como la gliotransmisión, son esenciales para llevar a cabo las funciones nerviosas, desde un sencillo reflejo a la función cognoscitiva más sofisticada. La glioplasticidad es un fenómeno que ocurre en paralelo a la neuroplasticidad mediante el cual se optimizan las funciones de los circuitos neuronales. Además, las células gliales tienen la capacidad de activarse pasando a un nuevo estado en el aparecen nuevas funciones (gliosis)


From birth to death, neurons are actively and dynamically accompanied by neuroglial cells in a very close morphological and functional relationship. The results of their study in the last years revolutionized the concepts about the functionality of the CNS. Classically, three families of these cells in the CNS have been classically considered: astroglia, oligodendroglia and microglia. Many types and subtypes have been described by morphological and immunocytochemical methods, including NGR2+ cells, with a wide variety of pathophysiological effects on the neurons and neuronal circuits. Now, all these elements are considered of paramount importance in all proposed theories for explaining any physiological or pathological process in the CNS because they are involved in both, neuroprotection/neurorepair and neurodegeneration. Glio-glial, glio-neuronal and neuro-glial cell signaling pathways and glio-transmission are essential phenomena that support the brain functions, from a simple reflex to the most sophisticated higher mental function. Glioplasticity is a parallel phenomenon to neuroplasticity for optimizing the function of the neuronal circuits. Moreover, they possess the ability to change to a reactive status (gliosis), in which new functions are developed in their relationships with the neurons


Assuntos
Feminino , Humanos , Masculino , Sistema Nervoso Central/fisiopatologia , Neuroglia/fisiologia , Astrócitos/fisiologia , Oligodendroglia/fisiologia , Microglia/fisiologia , Transmissão Sináptica/fisiologia , Degeneração Neural , Gliose , Plasticidade Neuronal/fisiologia
12.
Rev. neurol. (Ed. impr.) ; 59(3): 121-128, 1 ago., 2014. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-125695

RESUMO

Introducción. El fingolimod, un modulador del receptor de la esfingosina-1-fosfato (S1P) dotado de un mecanismo de acción novedoso, fue el primer tratamiento oral aprobado para la esclerosis múltiple remitente recurrente. Su unión a los receptores S1P1 de los linfocitos promueve la retención selectiva de los linfocitos T vírgenes y de memoria central en los tejidos linfoides secundarios, lo que impide su salida hacia el sistema nervioso central (SNC). Asimismo, el fingolimod atraviesa con facilidad la barrera hematoencefálica, y diversos estudios le atribuyen un efecto neuroprotector directo en el SNC. Objetivo. Revisar la información disponible acerca de los efectos centrales del fingolimod. Desarrollo. El desequilibrio entre los procesos lesivos y reparadores constituye un reflejo de la desmielinización crónica, la degeneración axonal y la gliosis, y parece contribuir a la discapacidad que la esclerosis múltiple acarrea. La facilidad con la que el fingolimod atraviesa la barrera hematoencefálica le permite actuar directamente sobre los receptores S1P localizados en las células del SNC. Una vez en el interior del SNC, ocupa los receptores S1P de los oligodendrocitos y de sus células precursoras, de los astrocitos, los microgliocitos y las neuronas, fomentando la remielinización, la neuroprotección y los procesos endógenos de regeneración. La eficacia evidenciada en los ensayos clínicos concuerda con un mecanismo de acción que incluiría efectos directos sobre las células del SNC. Conclusiones. Los datos disponibles indican que la eficacia del fingolimod en el tratamiento de la esclerosis múltiple se debe a su ambivalencia como molécula inmunomoduladora y moduladora directa de los receptores S1P del SNC. Tanto es así que estudios recientes le atribuyen efectos neuroprotectores en varios modelos que suscitan expectativas en torno a su posible aplicación terapéutica en la enfermedad de Alzheimer, el paludismo cerebral y el neuroblastoma, así como en la neuroprotección frente a la radioterapia craneal (AU)


Introduction. Fingolimod, a sphingosine-1-phosphate receptor modulator, was the first oral therapy approved for relapsingremitting multiple sclerosis, and shows a novel mechanism of action. Upon binding to S1P1 receptors in lymphocytes, the selective retention of naïve and central memory T cells in secondary lymphoid tissues is promoted, preventing their egress to the central nervous system (CNS). In addition, fingolimod readily crosses the blood brain barrier, and several reports suggest a direct neuroprotective effect in the CNS. Aim. To review the available data on the central effects of fingolimod. Development. Imbalances between damage and repair processes are a reflection of chronic demyelination, axonal degeneration and gliosis, and seem to contribute to multiple sclerosis associated disability. Given fingolimod readily crosses the blood brain barrier, it can exert its action directly on S1P receptors present in CNS cells. Fingolimod occupies S1P receptors in oligodendrocytes, oligodendrocyte precursor cells, astrocytes, microglial cells and neurons, promoting remyelination, neuroprotection, and endogenous regeneration processes. Efficacy results from clinical trials are consistent with a mechanism of action that includes direct effects in CNS cells. Conclusions. Current evidence suggests that the efficacy of fingolimod in the treatment of Multiple Sclerosis is due to its dual action as an immunomodulatory molecule and as a direct modulator of S1PRs in the CNS. In fact, recent reports propose that fingolimod has neuroprotective effects in several models, and open new avenues of potential therapeutic applications, such as Alzheimer’s disease, cerebral malaria, neuroblastoma and neuroprotection in cranial irradiation (AU)


Assuntos
Humanos , Esfingosina/farmacocinética , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Linfócitos T , Astrócitos , Oligodendroglia , Doenças Desmielinizantes/fisiopatologia , Doenças Neurodegenerativas/fisiopatologia , Microglia , Fármacos Neuroprotetores/farmacocinética
13.
Neurología (Barc., Ed. impr.) ; 29(5): 305-309, jun. 2014.
Artigo em Espanhol | IBECS | ID: ibc-122915

RESUMO

Introducción: La enfermedad de Alzheimer (EA) es una compleja enfermedad neurodegenerativa caracterizada por inflamación, neurotoxicidad, estrés oxidativo y gliosis reactiva. La microglía y los astrocitos no solo actúan como células presentadoras de antígenos, sino que constituyen células efectoras, liberando moléculas proinflamatorias que promueven la excitotoxicidad y la neurodegeneración. Objetivo: En la presente revisión bibliográfica se discute el papel de la glía, específicamente de la microglía y el astrocito en la fisiopatología de la EA y las posibles implicaciones terapéuticas. Desarrollo: La emergente evidencia del papel patogénico y la activación de vías de inflamación a partir de la microglía y el astrocito, los factores neurotóxicos liberados por estas células cuando están activadas, y cómo estos pueden desestabilizar la homeostasis del sistema nervioso central, sostienen la idea de que la inflamación inducida por la glía amplifica la EA. Conclusiones: La inhibición de la inflamación por inactivación de la glía, pudiera reducir la producción de factores que contribuyen con la toxicidad, resultando ser un beneficio clínico. La microglía y el astrocito constituyen blancos terapéuticos en el desarrollo de nuevos fármacos para combatir esta enfermedad. Estrategias terapéuticas diseñadas para contrarrestar el efecto perjudicial de la sobreactivación de estas poblaciones celulares deben ser investigadas


Introduction: Alzheimer (AD) disease is a complex neurodegenerative disease characterised by inflammation, neurotoxicity, oxidative stress, and reactive gliosis. Microglia and astrocytes not only act as antigen-presenting cells, but also function as effector cells releasing pro-inflammatory molecules that promote excitotoxicity and neurodegeneration Objective: In the present review we discuss the role of glia, specifically microglia and astrocytes, in the pathophysiology of AD and possible therapeutic implications. Development: The growing body of evidence suggesting that microglia and astrocytes play a pathogenic role and activate inflammation pathways, the neurotoxic factors released by these cells when activated, and the way these factors may disrupt the homeostasis of the central nervous system all support the hypothesis that glia-induced inflammation exacerbates AD. Conclusions: Inhibiting inflammation by deactivating glial cells may reduce the production of factors which contribute to neurotoxicity, and therefore result in clinical improvement. Microglia and astrocytes are therapeutic targets for the development of new drugs to combat this disease. Therapeutic strategies designed to counter the detrimental effects of overactivation of these cell populations should be investigated


Assuntos
Humanos , Doença de Alzheimer/fisiopatologia , Neuroglia/fisiologia , Microglia/fisiologia , Astrócitos/fisiologia , Neurogênese/fisiologia , Anti-Inflamatórios não Esteroides/uso terapêutico
15.
Eur. j. anat ; 17(1): 23-28, ene. 2013.
Artigo em Inglês | IBECS | ID: ibc-110446

RESUMO

Ecstasy (MDMA) is a popular drug a used recreationally with the rave culture and consumed in a high environment temperature. Repeated and prolonged MDMA ingestion is well known to cause depression, anxiety and aggression. The aim of this study was to evaluate the sub-chronic effects of MDMA on anxiety in Wistar rats and to determine astrocytes density in the rat hippocampus after anxiety. In this study, 28 adult male Wistar rats were used. The animals were distributed randomly in four groups, one sham group (receiving 1 ml/kg 0.9% saline solution) and three experimental groups: Exp. 1 (1.25 mg/kg/day MDMA), Exp. 2 (2.5 mg/kg/day MDMA), and Exp. 3 (5 mg/kg/day MDMA). The animals received Saline or MDMA for a week (sub-chronic period). An Elevated Plus Maze apparatus was used to examine anxiety levels in the rats. 24 h. after the last injection and behavioral test, the rat brains were withdrawn and fixed with 4% paraformaldehyde, and then - after histological processing - the slices of hippocampus were stained with PTAH for astrocytes. Our results showed that MDMA at 2.5 mg/kg/day for a week was most effective in causing anxiety. We found that the number of astrocytes was increased after this period. The greatest increase in astrocyte numbers was observed in the dentate gyrus of the5 mg/kg MDMA group. We concluded that the administration of MDMA over 7 days (sub-chronic period) can cause anxiety and can have an effect on the astrocyte density of the rat hippocampu (AU)


No disponible


Assuntos
Animais , Ratos , Ansiedade/induzido quimicamente , N-Metil-3,4-Metilenodioxianfetamina/farmacocinética , Astrócitos , Ratos , Drogas Desenhadas/farmacocinética , Hipocampo
16.
Trauma (Majadahonda) ; 22(4): 281-288, oct.-dic. 2011. ilus
Artigo em Espanhol | IBECS | ID: ibc-93861

RESUMO

Objetivo: Investigar la capacidad de trasplantes de astrocitos encapsulados en esferas de alginato de recuperar el déficit en la habilidad manual producida por la lesión de la corteza frontal, en ratas adultas. Material y metodología: Se utilizaron ratas Wistar, y se emplearon pruebas conductuales, cultivos celulares, técnica de encapsulación de células y trasplantes. Los animales se condicionaron en un test de habilidad motora fina y se determinó su mano preferente. Se lesionó la corteza frontal contralateral a la mano preferente y se evaluó la efectividad de la lesión mediante el test de conducta. En un grupo de animales lesionados se trasplantó astrocitos encapsulados en esferas de alginato en la cavidad producida por la lesión; en un segundo grupo, se trasplantó tejido cortical fetal; y en un tercer grupo, se implantó esferas de alginato sin células. Resultados: A los tres meses post-trasplante, tanto los animales con trasplantes de astrocitos encapsulados como con trasplantes de tejido cortical mejoraron el déficit motor inducido por la lesión. Los animales con trasplantes de esferas de alginato vacías no experimentaron mejoría. Conclusión: Los trasplantes de astrocitos encapsulados mejoran, a largo plazo, el deficit motor. El alginato indujo efectos secundarios en el huésped (AU)


Objetive: To investigate whether transplants of encapsulated astrocytes in alginate spheres were able to recover the deficit in motor skills produced by frontal cortex lesion, in adult rats. Material and method: Male Wistar rats were used. Behavioral test, tissue culture, astrocyte transplants and immunocytochemical and histological techniques were applied. Animals were conditioned in a paw reaching for food task and the preferred paw determine. Lesion was produced in the frontal cortex contralateral to the preferred paw and the effectiveness of the lesion tested. In one group of lesion animals, encapsulated astrocytes in alginate spheres were implanted in the lesion cavity; in a second group, fetal cortical tissue was used as donor material; while in a third group empty alginate spheres were implanted. Results: Three months after grafting, the rats with encapsulated astrocyte or with fetal cortical tissue transplants ameliorated the lesion-induced motor deficit.The rats with implant of empty alginate spheres showed no improvement. Conclusion: Transplants of encapsulated astrocytes in alginate spheres induce a long- term improvement of motor lesion deficits. The alginate induced long-term side effects on the host (AU)


Assuntos
Animais , Masculino , Astrócitos/transplante , Córtex Pré-Frontal/lesões , Córtex Pré-Frontal , Córtex Motor/lesões , Córtex Motor/cirurgia , Córtex Motor , Aptidão/fisiologia , Comportamento Animal/fisiologia , Imuno-Histoquímica/métodos , Astrócitos , Córtex Pré-Frontal/fisiopatologia , Ratos Wistar/lesões , Ratos Wistar/cirurgia , Modelos Animais , Imuno-Histoquímica/tendências , Imuno-Histoquímica , Análise de Variância
17.
Eur. j. anat ; 15(2): 85-97, mayo 2011. ilus
Artigo em Inglês | IBECS | ID: ibc-108078

RESUMO

Astrocytes play crucial roles in the organization, function and maintenance of neurons and neuronal circuits. Apart from reports on reactive gliosis after auditory/vestibular injuries, few authors have focused their attention on the astroglial cytoarchytecture of the cochlear nuclei (CN). In this qualitative immunohistochemical study, we analyse the distribution of the astrocytic markers glial fibrillary acidic protein (GFAP), glutamine synthetase (GS), and S-100 protein (S-100) in the adult CN of twelve young adult male rats (AU)


No disponible


Assuntos
Animais , Imuno-Histoquímica/métodos , Astrócitos/ultraestrutura , Núcleo Coclear/ultraestrutura , Núcleo Mediodorsal do Tálamo/ultraestrutura , Neuregulina-1/ultraestrutura , Glutamina , Proteínas S100 , Ácido Glutâmico , Ácido gama-Aminobutírico
18.
Actas esp. psiquiatr ; 38(5): 278-284, sept.-oct. 2010. ilus, graf, tab
Artigo em Espanhol | IBECS | ID: ibc-88708

RESUMO

Introducción. La importancia de las células gliales en la función del sistema nervioso y en su patología ha sido objeto de múltiples estudios en los últimos años. Concretamente se debate su papel en la acción de los antipsicóticos. Nuestro estudio analiza la reactividad glial en ratas tratadas con antipsicóticos. Metodología. En un primer estudio ultraestructural del núcleo arcuato del hipotálamo, los animales fueron tratados con clorpromacina durante 40 días, sacrificándose al final del tratamiento y tras 20 días de descanso. En otra serie de estudios, con el microscopio de luz y con técnicas inmunohistoquímicas valoramos la reacción a la proteína glial fibrilar ácida (GFAP) en seis regiones del sistema nervioso central de ratas tratadas con antipsicóticos típicos y atípicos. Resultados. Con el microscopio electrónico, las ratas tratadas mostraron una reducción significativa de las sinapsis axosomáticas sobre las neuronas del núcleo arcuato del hipotálamo, así como un incremento de la presencia glial evidenciable por la mayor cantidad de laminillas de astrocitos. Las modificaciones mencionadas son reversibles, tendiendo a normalizarse en los animales sacrificados a los 20 días de finalizado el tratamiento. En el estudio inmunohistoquímico la reacción astrocitaria fue muy importante en el territorio del núcleo accumbens con todos los antipsicóticos, moderada en la corteza cingular, aunque sólo con los atípicos, y discreta en el resto de las regiones. Conclusiones. Nuestros resultados confirman que las células gliales son diana de los antipsicóticos, lo que ha de contribuir a entender mejor la acción de estos fármacos y el papel de las células gliales en el normal funcionamiento del sistema nervioso y en la enfermedad mental (AU)


Introduction. The importance of the glial cells in the function of the nervous system and in its pathology has been the object of multiple studies in the last years. Specifically, their role in the action of the antipsychoticsis debated. Our study has analyzed glial reactivity in rats treated with antipsychotics. Methodology. In a first ultrastructural study of the arcuate nucleus of the hypothalamus, the animals were treated with chlorpromazine for 40 days, and were sacrificed at the end of the treatment, after 20 days of rest without treatment. In another series of studies, with the light microscope and immunohistochemistry we evaluated the immunoreactivity of the glial fibrillary acidic protein (GFAP) in six regions of the central nervous system ofrats treated with typical and atypical antipsychotics. Results. With the electron microscope, the animals treated with chlorpromazine showed a significant reduction of the axosomatic synapses on the neurons of the hypothalamic arcuate nucleus and an increase of glial presence, as noted by the greater amount of astrocyte processes. The mentioned modifications were reversible, tending to normalize in a group of animals sacrificed 20 days after completion of the treatment. In the immunohistochemical study, the glial reaction was important in the territory of the nucleus accumbens with all the antipsychotics, moderate in the cingulate cortex, although only with atypical antipsychotics, and scarcely significant in the rest of the regions. Conclusions. Our results confirm that the glial cells are targets of the antipsychotic action, and this will allow us to better understand the action of these drugs and the role of the glial cells in the normal function of the nervous system and in the mental disease (AU)


Assuntos
Animais , Ratos , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Antipsicóticos/farmacologia , Psiquiatria/educação , Psiquiatria/métodos , Astrócitos , Astrócitos/patologia , Sistema Nervoso/anatomia & histologia , Sistema Nervoso/patologia , Haloperidol/administração & dosagem , Haloperidol/efeitos adversos , Haloperidol/toxicidade , Clomipramina/administração & dosagem , Clomipramina/efeitos adversos , Clomipramina/toxicidade
20.
Rev. neurol. (Ed. impr.) ; 47(11): 582-587, 1 dic., 2008. ilus
Artigo em Es | IBECS | ID: ibc-71703

RESUMO

Introducción. La epilepsia es uno de los mayores trastornos neurológicos, afectando a cerca del 0,5-2% de la población mundial. Se caracteriza por la aparición de crisis espontáneas de forma recurrente. A pesar de los avances en el entendimiento de la epilepsia, las bases celulares exactas por las que ocurre la epilepsia humana no están claras. Desarrollo. Actualmente, el papel de los astrocitos en la modulación de la actividad neuronal y la transmisión sináptica está consolidado,ya que estas células se han convertido en unos actores importantes en el manejo de la información en el sistema nervioso. Estas características pueden hacen pensar en los astrocitos como elementos que poseen un papel importante, cuanto menos, en la epileptogénesis. Numerosos autores relacionan la rotura de la barrera hematoencefálica con la epilepsia, lo que origina laentrada masiva de albúmina al cerebro, donde ésta sería captada por los astrocitos, convirtiéndose en un factor importante en la alteración de su actividad y desencadenando cambios en ellos que conducirían a la epileptogénesis. Conclusión. A la vista de los datos observados para estos dos factores (astrocitos y albúmina), sin duda debería plantearse la realización de estudios para conocer en profundidad su implicación en la epileptogénesis y su posible uso como dianas terapéuticas


Introduction. Epilepsy is one of the major neurological disorders characterized by spontaneous and recurrentseizures. Despite progress in the understanding of epilepsy, the exact network underlying the seizures is unclear. Development. Actually the role of astrocytes in modulation of neuronal activity and the synaptic transmission is clear, making astrocytes asimportant players in processing of information in the central nervous system. These characteristics make us think that astrocytes have an important role in the epileptogenesis. Disruption of blood brain-barrier let the pass of albumin, and it could uptake into astrocytes. Numerous authors suggest that this can contribute to epileptogenesis. Conclusion. In view thedata obtained from these factors (astrocytes and albumin), future studies will undoubted further to know its relation with epileptogenesis in humans and as therapeutics aims


Assuntos
Humanos , Astrócitos/imunologia , Epilepsia/etiologia , Albuminas/imunologia , Epilepsia/imunologia , Fator de Crescimento Transformador beta/imunologia , Ácido Glutâmico/imunologia , Sinapis/imunologia
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