RESUMEN
Levetiracetam (LEV) is being used by women with reproductive-age epilepsy at a significantly higher rate. The purpose of the study was to assess how levetiracetam treatment during pregnancy affected the offspring's weight and cerebellum. Forty pregnant rats were divided into two groups (I, II). Two smaller groups (A, B) were created from each group. The rats in group I were gavaged with approximately 1.5 mL/day of distilled water either continuously during pregnancy (for subgroup IA) or continuously during pregnancy and 14 days postpartum (for subgroup IB). The rats in group II were gavaged with about 1.5 mL/day of distilled water (containing 36 mg levetiracetam) either continuously during pregnancy (for subgroup IA) or continuously during pregnancy and 14 days postpartum (for subgroup IB). After the work was completed, the body weight of the pups in each group was recorded, and their cerebella were analyzed histologically and morphometrically. Following levetiracetam treatment, the offspring showed decreased body weight and their cerebella displayed delayed development and pathological alterations. These alterations manifested as, differences in the thicknesses of the layers of cerebellar cortex as compared to the control groups; additionally, their cells displayed cytoplasmic vacuolation, nuclear alterations, fragmented rough endoplasmic reticulum and lost mitochondrial cristae. Giving levetiracetam to pregnant and lactating female rats had a negative impact on the body weight and cerebella of the offspring. Levetiracetam should be given with caution during pregnancy and lactation.
Asunto(s)
Anticonvulsivantes , Corteza Cerebelosa , Levetiracetam , Animales , Levetiracetam/farmacología , Femenino , Embarazo , Ratas , Anticonvulsivantes/toxicidad , Anticonvulsivantes/farmacología , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/patología , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/patología , Piracetam/análogos & derivados , Piracetam/farmacología , Ratas WistarRESUMEN
The cerebellum has a long, protracted developmental period that spans from the embryonic to postnatal periods; as a result, it is more sensitive to intrauterine and postnatal insults like nutritional deficiencies. Folate is crucial for foetal and early postnatal brain development; however, its effects on cerebellar growth and development are unknown. The aim of this study was to examine the effects of maternal folate intake on the histomorphology and cell density of the developing cerebellum. Twelve adult female rats (rattus norvegicus) were randomly assigned to one of four premixed diet groups: standard (2 mg/kg), folate-deficient (0 mg/kg), folate-supplemented (8 mg/kg) or folate supra-supplemented (40 mg/kg). The rats started their diets 14 days before mating and consumed them throughout pregnancy and lactation. On postnatal days 1, 7, 21 and 35, five pups from each group were sacrificed, and their brains were processed for light microscopic analysis. Histomorphology and cell density of the external granule, molecular, Purkinje and internal granule layers were obtained. The folate-deficient diet group had smaller, dysmorphic cells and significantly lower densities of external granule, molecular, Purkinje and internal granule cells. Although the folate-enriched groups had greater cell densities than the controls, the folate-supplemented group had considerably higher cell densities than the supra-supplemented group. The folate supra-supplemented group had ectopic Purkinje cells in the internal granule cell layer. These findings imply that a folate-deficient diet impairs cellular growth and reduces cell density in the cerebellar cortex. On the other hand, folate supplementation increases cell densities, but there appears to be an optimal dose of supplementation since excessive folate levels may be detrimental.
Asunto(s)
Animales Recién Nacidos , Corteza Cerebelosa , Ácido Fólico , Animales , Femenino , Ácido Fólico/administración & dosificación , Ácido Fólico/farmacología , Ratas , Embarazo , Recuento de Células , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/crecimiento & desarrollo , Corteza Cerebelosa/patología , Efectos Tardíos de la Exposición Prenatal/patología , Suplementos Dietéticos , Deficiencia de Ácido Fólico/patología , Ratas Sprague-Dawley , Dieta , Masculino , Factores de Edad , Neuronas/efectos de los fármacos , Neuronas/patologíaRESUMEN
Genetic differences in cerebellar sensitivity to alcohol (EtOH) influence EtOH consumption phenotype in animal models and contribute to risk for developing an alcohol use disorder in humans. We previously determined that EtOH enhances cerebellar granule cell (GC) tonic GABAAR currents in low EtOH consuming rodent genotypes, but suppresses it in high EtOH consuming rodent genotypes. Moreover, pharmacologically counteracting EtOH suppression of GC tonic GABAAR currents reduces EtOH consumption in high alcohol consuming C57BL/6J (B6J) mice, suggesting a causative role. In the low EtOH consuming rodent models tested to date, EtOH enhancement of GC tonic GABAAR currents is mediated by inhibition of neuronal nitric oxide synthase (nNOS) which drives increased vesicular GABA release onto GCs and a consequent enhancement of tonic GABAAR currents. Consequently, genetic variation in nNOS expression across rodent genotypes is a key determinant of whether EtOH enhances or suppresses tonic GABAAR currents, and thus EtOH consumption. We used behavioral, electrophysiological, and immunocytochemical techniques to further explore the relationship between EtOH consumption and GC GABAAR current responses in C57BL/6N (B6N) mice. B6N mice consume significantly less EtOH and achieve significantly lower blood EtOH concentrations than B6J mice, an outcome not mediated by differences in taste. In voltage-clamped GCs, EtOH enhanced the GC tonic current in B6N mice but suppressed it in B6J mice. Immunohistochemical and electrophysiological studies revealed significantly higher nNOS expression and function in the GC layer of B6N mice compared to B6Js. Collectively, our data demonstrate that despite being genetically similar, B6N mice consume significantly less EtOH than B6J mice, a behavioral difference paralleled by increased cerebellar nNOS expression and opposite EtOH action on GC tonic GABAAR currents in each genotype.
Asunto(s)
Consumo de Bebidas Alcohólicas/fisiopatología , Alcoholismo/fisiopatología , Depresores del Sistema Nervioso Central/farmacología , Corteza Cerebelosa , Fenómenos Electrofisiológicos , Etanol/farmacología , Óxido Nítrico Sintasa de Tipo I , Receptores de GABA-A , Animales , Conducta Animal/fisiología , Depresores del Sistema Nervioso Central/administración & dosificación , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/metabolismo , Modelos Animales de Enfermedad , Fenómenos Electrofisiológicos/efectos de los fármacos , Fenómenos Electrofisiológicos/fisiología , Etanol/administración & dosificación , Masculino , Ratones , Ratones Endogámicos C57BL/genética , Óxido Nítrico Sintasa de Tipo I/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo I/metabolismo , Receptores de GABA-A/efectos de los fármacos , Receptores de GABA-A/fisiología , Especificidad de la EspecieRESUMEN
The brain functions can be reversibly modulated by the action of general anesthetics. Despite a wide number of pharmacological studies, an extensive analysis of the cellular determinants of anesthesia at the microcircuits level is still missing. Here, by combining patch-clamp recordings and mathematical modeling, we examined the impact of sevoflurane, a general anesthetic widely employed in the clinical practice, on neuronal communication. The cerebellar microcircuit was used as a benchmark to analyze the action mechanisms of sevoflurane while a biologically realistic mathematical model was employed to explore at fine grain the molecular targets of anesthetic analyzing its impact on neuronal activity. The sevoflurane altered neurotransmission by strongly increasing GABAergic inhibition while decreasing glutamatergic NMDA activity. These changes caused a notable reduction of spike discharge in cerebellar granule cells (GrCs) following repetitive activation by excitatory mossy fibers (mfs). Unexpectedly, sevoflurane altered GrCs intrinsic excitability promoting action potential generation. Computational modelling revealed that this effect was triggered by an acceleration of persistent sodium current kinetics and by an increase in voltage dependent potassium current conductance. The overall effect was a reduced variability of GrCs responses elicited by mfs supporting the idea that sevoflurane shapes neuronal communication without silencing neural circuits.
Asunto(s)
Anestésicos por Inhalación/farmacología , Sevoflurano/farmacología , Transmisión Sináptica/efectos de los fármacos , Animales , Biomarcadores , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/fisiología , Modelos Biológicos , Neuronas/efectos de los fármacos , Neuronas/fisiología , Neurotransmisores/metabolismo , Técnicas de Placa-Clamp , Ratas , Potenciales Sinápticos/efectos de los fármacos , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Sofosbuvir is a promising antiviral drug against chronic hepatitis C virus. Although it is characterized by its high efficacy, its adverse effects on nervous tissue are still unclear. Saffron is known for its neuroprotective property. This is a biochemical, histological and immunohistochemical study of the effect of sofosbuvir on the cerebellar cortex of rat and the possible ameliorating role of saffron's aqueous extract. Twenty-four adult male Wistar albino rats were equally divided into four groups; control, saffron extract-treated, sofosbuvir-treated (41.1 mg/kg/day for 6 weeks) and group concomitantly treated with saffron extract and sofosbuvir. Sofosbuvir-treated group recorded a significant increase in cerebellar malondialdehyde level coupling with a significant decrease in tissue glutathione and superoxide dismutase. Light microscopy revealed reduced number of Purkinje cells. The granular layer depicted many granular cells and Bergmann astrocytes with nuclear and cytoplasmic alterations. Electron microscopy revealed disorganized molecular layer with disarranged myelinated axons and disrupted mitochondria. Few shrunken Purkinje cells showed electron-dense cytoplasm and rarefied nuclei, indistinct nuclear envelope and dilated perinuclear space, areas of vacuolated cytoplasm, fragmented rough endoplasmic reticulum and few dark mitochondria. Some axons with tiny mitochondria were detected. A significant upregulation in immunohistochemical expression of GFAP-positive astrocytes was recorded. Concomitant administration of saffron extract significantly improved all studied parameters. Saffron extract is beneficial in ameliorating sofosbuvir-induced cerebellar morphological changes mainly through its antioxidant and neuroprotective properties.
Asunto(s)
Antivirales/farmacología , Corteza Cerebelosa/efectos de los fármacos , Crocus , Extractos Vegetales/farmacología , Sofosbuvir/farmacología , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Corteza Cerebelosa/metabolismo , Glutatión/metabolismo , Masculino , Malondialdehído/metabolismo , Células de Purkinje/efectos de los fármacos , Células de Purkinje/metabolismo , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismoRESUMEN
RNA-sequencing (RNA-seq) analysis of gene expression and alternative splicing should be routine and robust but is often a bottleneck for biologists because of different and complex analysis programs and reliance on specialized bioinformatics skills. We have developed the '3D RNA-seq' App, an R shiny App and web-based pipeline for the comprehensive analysis of RNA-seq data from any organism. It represents an easy-to-use, flexible and powerful tool for analysis of both gene and transcript-level gene expression to identify differential gene/transcript expression, differential alternative splicing and differential transcript usage (3D) as well as isoform switching from RNA-seq data. 3D RNA-seq integrates state-of-the-art differential expression analysis tools and adopts best practice for RNA-seq analysis. The program is designed to be run by biologists with minimal bioinformatics experience (or by bioinformaticians) allowing lab scientists to analyse their RNA-seq data. It achieves this by operating through a user-friendly graphical interface which automates the data flow through the programs in the pipeline. The comprehensive analysis performed by 3D RNA-seq is extremely rapid and accurate, can handle complex experimental designs, allows user setting of statistical parameters, visualizes the results through graphics and tables, and generates publication quality figures such as heat-maps, expression profiles and GO enrichment plots. The utility of 3D RNA-seq is illustrated by analysis of data from a time-series of cold-treated Arabidopsis plants and from dexamethasone-treated male and female mouse cortex and hypothalamus data identifying dexamethasone-induced sex- and brain region-specific differential gene expression and alternative splicing.
Asunto(s)
Empalme Alternativo , Arabidopsis/metabolismo , Corteza Cerebelosa/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Hipotálamo/metabolismo , RNA-Seq/métodos , ARN/genética , Animales , Arabidopsis/efectos de los fármacos , Corteza Cerebelosa/efectos de los fármacos , Frío , Biología Computacional/métodos , Dexametasona/farmacología , Glucocorticoides/farmacología , Hipotálamo/efectos de los fármacos , Ratones , ARN/metabolismo , Programas InformáticosRESUMEN
BACKGROUND: The excessive exposure to silver nanoparticles (Ag-NPs) has raised concerns about their possible risks to the human health. The brain is a highly vulnerable organ to nano-silver harmfulness. The aim of this work was to evaluate the impacts of Ag-NPs exposure on the cerebellar cortex of rats. METHODS: Rats were assigned to: Control, vehicle control and Ag-NP-exposed groups (at doses of 10 mg and 30 mg/kg/day). Samples were processed for light and electron microscopy examinations. Immunohistochemical localization of c-Jun N-terminal kinase (JNK), nuclear factor kappa beta (NF-κB) and calbindin D28k (CB) proteins was performed. Analyses of expression of DNA damage inducible transcript 4 (Ddit4), flavin containing monooxygenase 2 (FMO2) and thioredoxin-interacting protein (Txnip) genes were done. Serum levels of inflammatory cytokines were also measured. RESULTS: Ag-NPs enhanced apoptosis as evident by upregulation of Ddit4 gene expressions and JNK protein immune expressions. Alterations of redox homeostasis were verified by enhancement of Txnip and FMO2 gene expressions, favoring the activation of inflammatory responses by increasing NF-κB protein immune expressions and serum inflammatory mediator levels. Another cytotoxic effect was the reduction of immune expressions of the calcium regulator CB. CONCLUSION: Ag-NPs exposure provoked biochemical, cellular and molecular changes of rat cerebellar cortex in a dose-dependent manner.
Asunto(s)
Corteza Cerebelosa/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Plata/toxicidad , Animales , Apoptosis/efectos de los fármacos , Biomarcadores/metabolismo , Masculino , FN-kappa B/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas WistarRESUMEN
Single-cell RNA sequencing (scRNA-seq) has become an empowering technology to profile the transcriptomes of individual cells on a large scale. Early analyses of differential expression have aimed at identifying differences between subpopulations to identify subpopulation markers. More generally, such methods compare expression levels across sets of cells, thus leading to cross-condition analyses. Given the emergence of replicated multi-condition scRNA-seq datasets, an area of increasing focus is making sample-level inferences, termed here as differential state analysis; however, it is not clear which statistical framework best handles this situation. Here, we surveyed methods to perform cross-condition differential state analyses, including cell-level mixed models and methods based on aggregated pseudobulk data. To evaluate method performance, we developed a flexible simulation that mimics multi-sample scRNA-seq data. We analyzed scRNA-seq data from mouse cortex cells to uncover subpopulation-specific responses to lipopolysaccharide treatment, and provide robust tools for multi-condition analysis within the muscat R package.
Asunto(s)
Perfilación de la Expresión Génica/métodos , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Transcriptoma , Animales , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/metabolismo , Análisis por Conglomerados , Biología Computacional , Simulación por Computador , Lipopolisacáridos/efectos adversos , Masculino , Ratones , Modelos Estadísticos , ARN Citoplasmático Pequeño , Transducción de Señal , Programas InformáticosRESUMEN
In humans, pyruvate dehydrogenase complex (PDC) deficiency impairs brain energy metabolism by reducing the availability of the functional acetylCoA pool. This "hypometabolic defect" results in congenital lactic acidosis and abnormalities of brain morphology and function, ranging from mild ataxia to profound psychomotor retardation. Our previous study showed reduction in total cell number and dendritic arbors in the cerebellar Purkinje cells in systemic PDCdeficient mice. Phenylbutyrate has been shown to increase PDC activity in cultured fibroblasts from PDCdeficient patients. Hence, we investigated the effects of postnatal (days 235) phenylbutyrate administration on the cerebellar Purkinje cell population in PDCdeficient female mice. Histological analyses of different regions of cerebellar cortex from the brainspecific PDCdeficient salineinjected mice revealed statistically significant reduction in the Purkinje cell density and increased cell size of the individual Purkinje cell soma compared to control PDCnormal, salineinjected group. Administration of phenylbutyrate to control mice did not cause significant changes in the Purkinje cell density and cell size in the studied regions. In contrast, administration of phenylbutyrate variably lessened the ill effects of PDC deficiency on Purkinje cell populations in different areas of the cerebellum. Our results lend further support for the possible use of phenylbutyrate as a potential treatment for PDC deficiency.
Asunto(s)
Encéfalo/efectos de los fármacos , Neuronas/efectos de los fármacos , Fenilbutiratos/farmacología , Células de Purkinje/efectos de los fármacos , Animales , Corteza Cerebelosa/efectos de los fármacos , Cerebelo/efectos de los fármacos , Modelos Animales de Enfermedad , Ratones Transgénicos , Fenilbutiratos/metabolismo , Células de Purkinje/citologíaRESUMEN
N-methyl-D-aspartate receptors (NMDARs) are expressed in granule cell and involve in mossy fiber-granule cell (MF-GC) synaptic transmission in cerebellar cortex. In the absence GABAA receptor activity, we here studied the role of NMDARs during the facial stimulation evoked MF-GC synaptic transmission in urethane-anesthetized mice using electrophysiological recording technique and pharmacological methods. Our results showed that facial stimuli train (20â¯Hz, 5 pulses) evoked 5 field potential responses (N1-N5) in mouse cerebellar granular layer, which identified MF-GC synaptic transmission. Blocking NMDARs induced significant depression in the amplitude of N2 to N5, accompanied with significant decrease in pulse ratios, area under the curve (AUC) and half-width of N1. A selective GluN2A antagonist, PEAQX (10 µM) also produced significant depression in the amplitude of N2 to N5, and decreases in pulse ratios. However, a selective GluN2B antagonist, TCN-237 (10 µM) did not significantly attenuate the facial stimuli train-induced mossy fiber-granule cell synaptic transmission. Application of NMDA (1⯵M) produced increases in the AUC and half-width of Ron, as well the amplitude and AUC of Roff, which was reversed by following application of PEAQX. Our present results indicated that NMDARs, especially GluN2A contribute to the facial stimulation-evoked MF-GC synaptic transmission, suggesting that the NMDARs play an important role during the lateral sensory information synaptic transmission in the cerebellar granular layer in vivo in mice.
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Corteza Cerebelosa/fisiología , Neuronas/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Transmisión Sináptica/fisiología , Animales , Corteza Cerebelosa/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/farmacología , Ratones , Ratones Endogámicos ICR , N-Metilaspartato/farmacología , Neuronas/efectos de los fármacos , Estimulación Física , Quinoxalinas/farmacología , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Transmisión Sináptica/efectos de los fármacos , Valina/análogos & derivados , Valina/farmacología , Vibrisas/fisiologíaRESUMEN
BACKGROUND: Diabetes mellitus is the disease, termed either by insulin paucity or resistance and hyperglycemia. The selection of the cerebellum was built on its specific functions. The aim of this study was to investigate a comparison between the possible therapeutic effects of MSCs and curcumin against fluctuations in the cerebellar cortex of STZ-induced diabetic albino rats. MATERIALS AND METHODS: Forty rats were divided into five groups: control, sham control, streptozotocin-induced diabetes, diabetes and MSCs administered and diabetes and curcumin administered. Light microscopic (H&E), immune-histochemical; Glial fibrillary acidic protein (GFAP), real-time PCR; phospholipase-C (PLC) and α-synuclein, histomorphometric analysis, oxidative / anti-oxidatants; malondialdehyde (MDA)/ superoxide dismutase (SOD) glutathione (GSH) and were made. RESULTS: The histopathological examination of the STZ-induced diabetic rats revealed alterations in the molecular, purkinje and granular layers. Abnormal organizations, vacuolation, patchy loss of purkinje cells were detected. Some purkinje cells migrated into the granular layer.Hemorrhage in pia mater outspreading to cerebellar layers is discerned. Purkinje cells showed karyorrhexis. The mean value of area percentage for GFAP immune- reactivity revealed 360 % significant increase compared to that of the control group. Also, MDA level was significantly increased while the SOD and GSH levels were significantly lower when compared to the control group. Meanwhile, mean values of PLC demonstrated significant decrease, while α-synuclein levels displayed a significant increment in the diabetic group. Administration of curcumin and MSCs extremely ameliorated the previous alterations. CONCLUSION: the deleterious alterations on the cerebellar cortex induced by diabetes were obviously improved when treated with either MSCs or curcumin.
Asunto(s)
Corteza Cerebelosa/efectos de los fármacos , Curcumina/farmacología , Diabetes Mellitus Experimental/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Células Madre Mesenquimatosas , Fosfolipasas de Tipo C/metabolismo , alfa-Sinucleína/metabolismo , Animales , Glucemia/metabolismo , Corteza Cerebelosa/metabolismo , Glutatión/metabolismo , Masculino , Malondialdehído/metabolismo , Estrés Oxidativo/efectos de los fármacos , Células de Purkinje/efectos de los fármacos , Células de Purkinje/metabolismo , Ratas , Transducción de Señal/efectos de los fármacos , Superóxido Dismutasa/metabolismoRESUMEN
The mechanism of cognitive dysfunction in diabetes is still unclear. Recently, studies have shown that the cerebellum is involved in cognition. Furthermore, diabetes-induced cerebellar alterations is related to vascular changes. Therefore, we aimed to explore the roles of vascular function in diabetes-induced cerebellar damage and motor learning deficits. Type 1 diabetes was induced by a single injection of streptozotocin in Sprague-Dawley rats. Motor learning was assessed by beam walk test and beam balance test. The pathological changes of the cerebellum were assessed by Hematoxylin and eosin staining and Nissl staining. Apoptosis was evaluated by anti-caspase-3 immunostaining. Protein expression was evaluated by western blotting and double immunofluorescence. Our results have shown that motor learning was impaired in diabetic rats, coupled with damaged Purkinje cells and decreased capillary density in the cerebellum. In addition, the protein expression of neuronal NOS, inducible NOS, endothelial NOS, total nitric oxide, vascular endothelial growth factor and its cognate receptor Flk-1 was decreased in the cerebellum. Gastrodin treatment ameliorated neuronal damage and restored protein expression of relevant factors. Arising from the above, it is suggested that vascular dysfunction and NO signaling deficits in the cerebellum may be the underlying mechanism of early manifestations of cognitive impairment in diabetes, which could be ameliorated by gastrodin intervention.
Asunto(s)
Conducta Animal/efectos de los fármacos , Alcoholes Bencílicos/uso terapéutico , Disfunción Cognitiva/tratamiento farmacológico , Glucósidos/uso terapéutico , Locomoción/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/enzimología , Corteza Cerebelosa/patología , Disfunción Cognitiva/epidemiología , Diabetes Mellitus Experimental/complicaciones , Endotelio Vascular/efectos de los fármacos , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/metabolismo , Células de Purkinje/efectos de los fármacos , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
The spontaneous activity pattern of cortical neurons in dissociated culture is characterized by burst firing that is highly synchronized among a wide population of cells. The degree of synchrony, however, is excessively higher than that in cortical tissues. Here, we employed polydimethylsiloxane (PDMS) elastomers to establish a novel system for culturing neurons on a scaffold with an elastic modulus resembling brain tissue, and investigated the effect of the scaffold's elasticity on network activity patterns in cultured rat cortical neurons. Using whole-cell patch clamp to assess the scaffold effect on the development of synaptic connections, we found that the amplitude of excitatory postsynaptic current, as well as the frequency of spontaneous transmissions, was reduced in neuronal networks grown on an ultrasoft PDMS with an elastic modulus of 0.5 kPa. Furthermore, the ultrasoft scaffold was found to suppress neural correlations in the spontaneous activity of the cultured neuronal network. The dose of GsMTx-4, an antagonist of stretch-activated cation channels (SACs), required to reduce the generation of the events below 1.0 event per min on PDMS substrates was lower than that for neurons on a glass substrate. This suggests that the difference in the baseline level of SAC activation is a molecular mechanism underlying the alteration in neuronal network activity depending on scaffold stiffness. Our results demonstrate the potential application of PDMS with biomimetic elasticity as cell-culture scaffold for bridging the in vivo-in vitro gap in neuronal systems.
Asunto(s)
Encéfalo/efectos de los fármacos , Corteza Cerebelosa/efectos de los fármacos , Neuronas/metabolismo , Andamios del Tejido/química , Animales , Encéfalo/metabolismo , Técnicas de Cultivo de Célula , Corteza Cerebelosa/metabolismo , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacología , Elasticidad/efectos de los fármacos , Elastómeros/química , Elastómeros/farmacología , Péptidos y Proteínas de Señalización Intercelular/farmacología , Neuronas/efectos de los fármacos , Ratas , Venenos de Araña/farmacologíaRESUMEN
Cardiac arrest (CA) yields poor neurological outcomes. Salubrinal (Sal), an endoplasmic reticulum (ER) stress inhibitor, has been shown to have neuroprotective effects in both in vivo and in vitro brain injury models. This study investigated the neuroprotective mechanisms of Sal in postresuscitation brain damage in a rodent model of CA. In the present study, rats were subjected to 6 min of CA and then successfully resuscitated. Either Sal (1 mg/kg) or vehicle (DMSO) was injected blindly 30 min before the induction of CA. Neurological status was assessed 24 h after CA, and the cortex was collected for analysis. As a result, we observed that, compared with the vehicle-treated animals, the rats pretreated with Sal exhibited markedly improved neurological performance and cortical mitochondrial morphology 24 h after CA. Moreover, Sal pretreatment was associated with the following: (1) upregulation of superoxide dismutase activity and a reduction in maleic dialdehyde content; (2) preserved mitochondrial membrane potential; (3) amelioration of the abnormal distribution of cytochrome C; and (4) an increased Bcl-2/Bax ratio, decreased cleaved caspase 3 upregulation, and enhanced HIF-1α expression. Our findings suggested that Sal treatment improved neurological dysfunction 24 h after CPR (cardiopulmonary resuscitation), possibly through mitochondrial preservation and stabilizing the structure of HIF-1α.
Asunto(s)
Lesiones Encefálicas/tratamiento farmacológico , Corteza Cerebelosa/efectos de los fármacos , Cinamatos/farmacología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Paro Cardíaco/fisiopatología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Tiourea/análogos & derivados , Aldehídos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/fisiopatología , Reanimación Cardiopulmonar , Caspasa 3/metabolismo , Corteza Cerebelosa/metabolismo , Corteza Cerebelosa/fisiopatología , Corteza Cerebelosa/ultraestructura , Citocromos c/metabolismo , Paro Cardíaco/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Microscopía Electrónica de Transmisión , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa-1/metabolismo , Tiourea/farmacologíaRESUMEN
Intracerebellar administration of cannabinoid agonists impairs cerebellum-dependent delay eyeblink conditioning (EBC) in rats. It is not known whether the cannabinoid-induced impairment in EBC is found with shorter interstimulus intervals (ISI), longer ISIs, or with trace EBC. Moreover, systemic administration of cannabinoid agonists does not impair trace EBC, suggesting that cannabinoid receptors within the cerebellum are not involved in trace EBC. To more precisely assess the effects of cannabinoids on cerebellar learning mechanisms the current study examined the effects of the cannabinoid agonist WIN55,212-2 (WIN) infusion into the area of the cerebellar cortex necessary for EBC (the eyeblink microzone) in rats during short delay (250 ms CS), long delay (750 ms CS), and trace (250 ms CS, 500 ms trace interval) EBC. WIN was infused into the eyeblink microzone 30 min before pretraining sessions and five EBC training sessions, followed by five EBC training sessions without infusions to assess recovery from drug effects and savings. WIN had no effect on spontaneous blinks or non-associative responses to the CS or US during the pretraining sessions. Short and long delay EBC were impaired by WIN but trace EBC was unaffected. The results indicate that trace EBC is mediated by mechanisms that are resistant to cannabinoid agonists.
Asunto(s)
Parpadeo/efectos de los fármacos , Agonistas de Receptores de Cannabinoides/farmacología , Corteza Cerebelosa/efectos de los fármacos , Condicionamiento Clásico/efectos de los fármacos , Condicionamiento Palpebral/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Benzoxazinas/farmacología , Agonistas de Receptores de Cannabinoides/administración & dosificación , Masculino , Morfolinas/farmacología , Naftalenos/farmacología , Ratas , Ratas Long-Evans , Factores de TiempoRESUMEN
OBJECTIVE: The cerebellum is involved in cognitive processing and emotion control. Cerebellar alterations could explain symptoms of schizophrenia spectrum disorder (SZ) and bipolar disorder (BD). In addition, literature suggests that lithium might influence cerebellar anatomy. Our aim was to study cerebellar anatomy in SZ and BD, and investigate the effect of lithium. METHODS: Participants from 7 centers worldwide underwent a 3T MRI. We included 182 patients with SZ, 144 patients with BD, and 322 controls. We automatically segmented the cerebellum using the CERES pipeline. All outputs were visually inspected. RESULTS: Patients with SZ showed a smaller global cerebellar gray matter volume compared to controls, with most of the changes located to the cognitive part of the cerebellum (Crus II and lobule VIIb). This decrease was present in the subgroup of patients with recent-onset SZ. We did not find any alterations in the cerebellum in patients with BD. However, patients medicated with lithium had a larger size of the anterior cerebellum, compared to patients not treated with lithium. CONCLUSION: Our multicenter study supports a distinct pattern of cerebellar alterations in SZ and BD.
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Antimaníacos/efectos adversos , Trastorno Bipolar/patología , Corteza Cerebelosa/patología , Compuestos de Litio/efectos adversos , Esquizofrenia/patología , Adulto , Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/tratamiento farmacológico , Corteza Cerebelosa/diagnóstico por imagen , Corteza Cerebelosa/efectos de los fármacos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/tratamiento farmacológico , Adulto JovenRESUMEN
CONTEXT: Fucoidan, a sulphated polysaccharide extracted from brown algae [Fucus vesiculosus Linn. (Fucaceae)], has multiple biological activities. OBJECTIVE: The effects of fucoidan on Ca2+ responses of rat neurons and its probable mechanisms with focus on glutamate receptors were examined. MATERIALS AND METHODS: The neurons isolated from the cortex and hippocampi of Wistar rats in postnatal day 1 were employed. The intracellular Ca2+ responses triggered by various stimuli were measured in vitro by Fura-2/AM. Fucoidan at 0.5 mg/mL or 1.5 mg/mL was applied for 3 min to determine its effects on Ca2+ responses. RT-PCR was used to determine the mRNA expression of neuron receptors treated with fucoidan at 0.5 mg/mL for 3 h. RESULTS: The Ca2+ responses induced by NMDA were 100% suppressed by fucoidan, and those induced by Bay K8644 90% in the cortical neurons. However, fucoidan has no significant effect on the Ca2+ responses of cortical neurons induced by AMPA or quisqualate. Meanwhile, the Ca2+ responses of hippocampal neurons induced by glutamate, ACPD or adrenaline, showed only a slight decrease following fucoidan treatment. RT-PCR assays of cortical and hippocampal neurons showed that fucoidan treatment significantly decreased the mRNA expression of NMDA-NR1 receptor and the primer pair for l-type Ca2+ channels, PR1/PR2. DISCUSSION AND CONCLUSIONS: Our data indicate that fucoidan suppresses the intracellular Ca2+ responses by selectively inhibiting NMDA receptors in cortical neurons and l-type Ca2+ channels in hippocampal neurons. A wide spectrum of fucoidan binding to cell membrane may be useful for designing a general purpose drug in future.
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Canales de Calcio Tipo L/metabolismo , Calcio/metabolismo , Neuronas/efectos de los fármacos , Polisacáridos/farmacología , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Ácido 3-piridinacarboxílico, 1,4-dihidro-2,6-dimetil-5-nitro-4-(2-(trifluorometil)fenil)-, Éster Metílico/farmacología , Animales , Células Cultivadas , Corteza Cerebelosa/citología , Corteza Cerebelosa/efectos de los fármacos , Agonistas de Aminoácidos Excitadores/farmacología , Ácido Glutámico/farmacología , Hipocampo/citología , Hipocampo/efectos de los fármacos , N-Metilaspartato/farmacología , Neuronas/metabolismo , Ratas , Ratas Wistar , Receptores AMPA/metabolismo , Receptores de Glutamato/metabolismo , Receptores de N-Metil-D-Aspartato/biosíntesis , Receptores de N-Metil-D-Aspartato/metabolismoRESUMEN
BACKGROUND: Danggui Buxue Tang (DBT) is a historical Chinese herbal decoction, and which has more than 800 years of applications. This herbal decoction solely contains two materials: Astragali Radix (AR) and Angelicae Sinensis Radix (ASR) at a weight ratio of 5:1. Clinically, DBT aims to improve anemia syndrome. In complementary and alternative medicine theory, the cause of neurodegenerative disease is proposed to be related with anemia. In line to this notion, low levels of hemoglobin and red blood cell have been reported in patients suffering from Alzheimer's disease (AD), a chronic neurodegenerative disease caused by ß-amyloid peptide (Aß) accumulation. Therefore, we would like to probe the neuroprotective functions of this ancient herbal formula in vitro. METHOD: The neuroprotective effects of DBT in the Aß-induced cell death were detected in cultured cortical neurons by multiple techniques, i.e. confocal and western blot. RESULTS: In the cultures, application of DBT reduced Aß-induced apoptosis rate in a dose-dependent manner. In Aß-treated cortical neurons, the expression ratio of Bcl2 to Bax was altered by DBT. In parallel, application of DBT markedly suppressed the Aß-induced expressions of apoptotic markers, i.e. cleaved-caspase 3/9 and PARP. CONCLUSION: Taken these results, DBT shows promising protective effects against Aß-induced stress or insult in cultured neurons.
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Apoptosis/efectos de los fármacos , Planta del Astrágalo/química , Corteza Cerebelosa/citología , Medicamentos Herbarios Chinos/farmacología , Neuronas/efectos de los fármacos , Sustancias Protectoras/farmacología , Enfermedad de Alzheimer/fisiopatología , Péptidos beta-Amiloides/metabolismo , Angelica sinensis/química , Animales , Muerte Celular/efectos de los fármacos , Células Cultivadas , Corteza Cerebelosa/efectos de los fármacos , Humanos , Neuronas/citología , RatasRESUMEN
Backgroud: Alzheimer disease is an age-related severe neurodegenerative pathology. The level of the third endogenous gas, hydrogen sulfide (H2S), is decreased in the brain of Alzheimer's disease (AD) patients compared with the brain of the age-matched normal individuals; also, plasma H2S levels are negatively correlated with the severity of AD. Recently, we have demonstrated that systemic H2S injections are neuroprotective in an early phase of preclinical AD. OBJECTIVES: This study focuses on the possible neuroprotection of a chronic treatment with an H2S donor and sulfurous water (rich of H2S) in a severe transgenic 3×Tg-AD mice model. METHOD: 3×Tg-AD mice at 2 different ages (6 and 12 months) were daily treated intraperitoneally with an H2S donor and sulfurous water (rich of H2S) for 3 months consecutively. We investigated the cognitive ability, brain morphological alterations, amyloid/tau cascade, excitotoxic, inflammatory and apoptotic responses. RESULTS: Three months of treatments with H2S significantly protected against impairment in learning and memory in a severe 3×Tg-AD mice model, at both ages studied, and reduced the size of Amyloid ß plaques with preservation of the morphological picture. This neuroprotection appeared mainly in the cortex and hippocampus, associated with reduction in activity of c-jun N-terminal kinases, extracellular signal-regulated kinases and p38, which have an established role not only in the phosphorylation of tau protein but also in the inflammatory and excitotoxic response. CONCLUSION: Our findings indicate that appropriate treatments with various sources of H2S, might represent an innovative approach to counteract early and severe AD progression in humans.
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Enfermedad de Alzheimer/tratamiento farmacológico , Sulfuro de Hidrógeno/farmacología , Factores de Edad , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/metabolismo , Modelos Animales de Enfermedad , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , MAP Quinasa Quinasa 7/metabolismo , MAP Quinasa Quinasa Quinasa 3/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Transgénicos , Placa Amiloide/metabolismo , Proteínas tau/metabolismoRESUMEN
BACKGROUND: Olive oil is a food additive and used in many biological studies as a solvent for other chemicals, including drugs. AIM: The present study aimed to investigate the effects of olive oil on rats' cerebellum structure and motor function. MATERIALS AND METHODS: Male rats were randomly divided into two groups orally receiving distilled water and olive oil (1 ml/kg/day). At the end of week 4, motor function was assessed in the rotarod test. The cerebellum was removed for stereo-logical assessment. Data were analyzed using a two-way repeated measures ANOVA for rotarod test and Kruskal-Wallis and Mann-Whitney U test for quantitative histological parameters. RESULTS: Performance of the olive oil-treated rats in fixed and accelerating speed rotarod was better and their riding time (endurance) was greater compared to the control group (p<0.05). However, no significant difference was found between the two groups regarding the total volume of the cerebellar hemisphere, its cortex, and deep cerebellar nuclei. The total number of the Purkinje, Bergman, and Golgi of the granular layer as well as neurons of the deep cerebellar nuclei was 26 - 36% higher in the olive oil-treated rats than in the distilled water treated group (p<0.03). CONCLUSION: The study findings suggest that olive oil has neuroprotective effects on the cerebellum and induces better performance of the rats in the rotarod.