RESUMEN
Dysregulation of calcium homeostasis has been hypothesized to play a role in Alzheimer's disease (AD) pathogenesis. Increased calcium levels can impair axonal transport, disrupt synaptic transmission, and ultimately lead to cell death. Given the potential role of calcium dyshomeostasis in AD, there is interest in testing the ability of already approved drugs targeting various calcium channels to affect amyloid pathology and other aspects of disease. The objective of this study was to test the effects of FDA-approved L-type calcium channel antagonist nimodipine on amyloid accumulation and dystrophic neurite formation in 5XFAD mice, a mouse model of amyloid pathology. 5XFAD transgenic mice and non-transgenic littermates were treated with vehicle or nimodipine-containing chow from two to eight months of age, then brains were harvested and amyloid pathology assessed by immunoblot and immunofluorescence microscopy analyses. Nimodipine was well tolerated and crossed the blood brain barrier, as expected, but there was no effect on Aß accumulation or on the relative amount of neuritic dystrophy, as assessed by either immunoblot, dot blot or immunofluorescence imaging of Aß42 and dystrophic neurite marker LAMP1. While we conclude that nimodipine treatment is not likely to improve amyloid pathology or decrease neuritic dystrophy in AD, it is worth noting that nimodipine did not worsen the phenotype suggesting its use is safe in AD patients.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Modelos Animales de Enfermedad , Neuritas/efectos de los fármacos , Distrofias Neuroaxonales/tratamiento farmacológico , Nimodipina/administración & dosificación , Placa Amiloide/tratamiento farmacológico , Administración Oral , Enfermedad de Alzheimer/patología , Animales , Bloqueadores de los Canales de Calcio/administración & dosificación , Femenino , Humanos , Masculino , Ratones , Ratones Transgénicos , Neuritas/patología , Distrofias Neuroaxonales/patología , Placa Amiloide/patologíaRESUMEN
Alzheimer's disease is a multifactorial neurodegenerative condition manifested through acute cognitive decline, amyloid plaque deposits and neurofibrillary tangles. Complete cure for this disease remains elusive as the conventional drugs address only a single molecular target while Alzheimer's disease involves a complex interplay of different sets of molecular targets and signaling networks. In this context, the possibility of employing multi-drug combinations to rescue neurons from the dysregulated metabolic changes is being actively investigated. The present work investigates a poly-herbal formulation, Brahmi Nei that has been traditionally used for anxiolytic disorders and immunomodulatory effects, for its efficiency in ameliorating cognitive decline through a combination of behavioral, biochemical, histopathological, gene and protein expression analyses. Our results reveal that the formulation shows excellent neuroregenerative properties, rescues neurons from inflammatory damage, reduces neuritic plaque deposits and improves working memory in rodent models with scopolamine-induced dementia. The microarray analysis shows that the formulation induces the expression of pro-survival pathways and positively modulates genes involved in memory consolidation, axonal growth and proliferation in a concentration-dependent manner with therapeutic concentrations restoring the normal conditions in the brain of the diseased animals. The neuritic spine morphology confirms the long-term memory potentiation through improved mushroom spine density, increased dendritic length and connectivity. Taken together, our study provides mechanistic evidence to prove that the traditional formulation can be a superior therapeutic strategy to treat cognitive decline when compared to the conventional mono-drug treatment.
Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/tratamiento farmacológico , Enfermedades del Sistema Nervioso Autónomo/psicología , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/psicología , Medicina de Hierbas , Animales , Enfermedades del Sistema Nervioso Autónomo/complicaciones , Axones/efectos de los fármacos , Axones/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Trastornos del Conocimiento/etiología , Dendritas/efectos de los fármacos , Dendritas/ultraestructura , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Composición de Medicamentos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Memoria a Corto Plazo/efectos de los fármacos , Regeneración Nerviosa/efectos de los fármacos , Neuritas/patología , Fitoterapia , Ratas , Ratas WistarRESUMEN
Cortex Mori Radicis extract (CMR) has various pharmacological properties, such as antiinflammatory, antiallergic and antihyperglycemic effects. However, the effects and mechanisms of CMR in the neuroregeneration of diabetic peripheral neuropathy (DPN) are unclear. In the present study, the effects of CMR on neurite outgrowth of dorsal root ganglia (DRG) neurons in diabetic rats were investigated and its underlying mechanisms were explored. SD rats were subjected to a highfat diet with lowdose streptozotocin to induce a Type II diabetes model with peripheral neuropathy. CMR was then applied for four weeks continuously with or without injection of small interfere (si)RNA targeting the transient receptor potential canonical channel 1 (TRPC1) via the tail vein. Blood glucose levels, the number of Nissl bodies, neurite outgrowth and growth cone turning in DRG neurons were evaluated. The expression of TRPC1 protein, Ca2+ influx and activation of the PI3K/AKT signaling pathway were also investigated. The results of the present study showed that CMR significantly lowered blood glucose levels, reversed the loss of Nissl bodies, induced neurite outgrowth and restored the response of the growth cone of DRG neurons in diabetic rats. CMR exerted neurite outgrowthpromoting effects by increasing TRPC1 expression, reducing Ca2+ influx and enhancing AKT phosphorylation. siRNA targeting TRPC1 in the CMR group abrogated its antidiabetic and neuroregenerative effects, suggesting the involvement of TRPC1 in the biological effects of CMR on DPN.
Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Neuropatías Diabéticas/tratamiento farmacológico , Morus , Neuritas/metabolismo , Proyección Neuronal/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Glucemia/efectos de los fármacos , Calcio/metabolismo , Células Cultivadas , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Neuropatías Diabéticas/sangre , Neuropatías Diabéticas/genética , Neuropatías Diabéticas/metabolismo , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/crecimiento & desarrollo , Ganglios Espinales/metabolismo , Masculino , Neuritas/efectos de los fármacos , Neuritas/patología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Cuerpos de Nissl/efectos de los fármacos , Cuerpos de Nissl/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Extractos Vegetales/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Canales Catiónicos TRPC/genética , Canales Catiónicos TRPC/metabolismo , Regulación hacia ArribaRESUMEN
Dystrophic neurites and activated microglia are one of the main neuropathological characteristics of Alzheimer's disease (AD). Although the use of supplements with omega-3 fatty acids has been associated with reduced risk and lessened AD pathology, it still remains elusive whether such a treatment could affect dystrophic neurites (DNs) formation and microglia/macrophage behavior in the early phase of disease. We analyzed the effects of short-term (3 weeks) fish oil supplementation on DNs formation, tau hyperphosphorylation, Amyloid-beta peptide 1-42 (Aß42) levels and microglial/macrophage response to AD pathology in the parietal cortex of 4-month-old 5xFAD mice, a mouse model of AD. The present study shows for the first time that short-term FO supplementation applied in presymptomatic stage of AD, alters the behaviour of microglia/macrophages prompting them to establish a physical barrier around amyloid plaques. This barrier significantly suppresses DNs formation through the reduction of both Aß content and tau hyperphosphorylation. Moreover, the short-term FO treatment neither suppresses inflammation nor enhances phagocytic properties of microglia/macrophages in the response to Aß pathology, the effects most commonly attributed to the fish oil supplementation. Our findings suggest that fish oil consumption may play an important role in modulating microglial/macrophage response and ameliorating the AD pathology in presymptomatic stage of Alzheimer's disease.
Asunto(s)
Enfermedad de Alzheimer/patología , Enfermedades Asintomáticas , Aceites de Pescado/farmacología , Macrófagos/efectos de los fármacos , Microglía/efectos de los fármacos , Neuritas/patología , Lóbulo Parietal/patología , Enfermedad de Alzheimer/inmunología , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Atrofia/prevención & control , Recuento de Células , Citocinas/metabolismo , Suplementos Dietéticos , Modelos Animales de Enfermedad , Macrófagos/inmunología , Ratones , Microglía/patología , Neuritas/efectos de los fármacos , Lóbulo Parietal/efectos de los fármacos , Fragmentos de Péptidos/metabolismo , Fagocitosis/efectos de los fármacos , Fosfoproteínas/metabolismo , Factores de Tiempo , Proteínas tau/metabolismoRESUMEN
MicroRNAs (miRNA) regulate fundamental biological processes, including neuronal plasticity, stress response, and survival. Here, we describe a neuroprotective function of miR-132, the miRNA most significantly downregulated in neurons in Alzheimer's disease. We demonstrate that miR-132 protects primary mouse and human wild-type neurons and more vulnerable Tau-mutant neurons against amyloid ß-peptide (Aß) and glutamate excitotoxicity. It lowers the levels of total, phosphorylated, acetylated, and cleaved forms of Tau implicated in tauopathies, promotes neurite elongation and branching, and reduces neuronal death. Similarly, miR-132 attenuates PHF-Tau pathology and neurodegeneration, and enhances long-term potentiation in the P301S Tau transgenic mice. The neuroprotective effects are mediated by direct regulation of the Tau modifiers acetyltransferase EP300, kinase GSK3ß, RNA-binding protein Rbfox1, and proteases Calpain 2 and Caspases 3/7. These data suggest miR-132 as a master regulator of neuronal health and indicate that miR-132 supplementation could be of therapeutic benefit for the treatment of Tau-associated neurodegenerative disorders.
Asunto(s)
MicroARNs/genética , Transducción de Señal/genética , Tauopatías/genética , Péptidos beta-Amiloides/genética , Animales , Muerte Celular , Ácido Glutámico/toxicidad , Humanos , Ratones , Ratones Transgénicos , MicroARNs/fisiología , Mutación/genética , Degeneración Nerviosa/genética , Degeneración Nerviosa/patología , Neuritas/patología , Neuronas/patología , Cultivo Primario de Células , Procesamiento Proteico-Postraduccional , ARN Largo no Codificante/genética , Proteínas tau/genéticaRESUMEN
The treatment goal in spinal cord injury (SCI) is to repair neurites and suppress cell apoptosis. Panax quinquefolius saponin (PQS) is the major active ingredient of American ginseng and has been demonstrated to have anti-inflammatory and anti-apoptotic roles in various diseases. However, the potential effect of PQS on the pathological process of acute SCI remains unknown. This work tested the effects of PQS on acute SCI and clarified its potential mechanisms. PQS treatment ameliorated the damage to spinal tissue and improved the functional recovery after SCI. PQS treatment inhibited endoplasmic reticulum (ER) stress and the associated apoptosis after acute SCI. PQS further abolished the triglyceride (TG)-induced ER stress and associated apoptosis in neuronal cultures. PQS appears to inhibit the ER-stress-induced neurite injury in PC12 cells. Our results suggest that PQS is a novel therapeutic agent for acute central nervous system injury.
Asunto(s)
Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Neuritas/efectos de los fármacos , Recuperación de la Función/efectos de los fármacos , Saponinas/uso terapéutico , Traumatismos de la Médula Espinal/tratamiento farmacológico , Enfermedad Aguda , Animales , Femenino , Neuritas/metabolismo , Neuritas/patología , Panax/química , Ratas Sprague-Dawley , Saponinas/aislamiento & purificación , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/patologíaRESUMEN
Estrogen receptors (ERs) α and ß are distributed in most tissues of women and men. ERs are bound by estradiol (E2), a natural hormone, and mediate the pleiotropic and tissue-specific effects of E2, such as proliferation of breast epithelial cells or protection and differentiation of neuronal cells. Numerous environmental molecules, called endocrine disrupting compounds, also interact with ERs. Phytoestrogens belong to this large family and are considered potent therapeutic molecules that act through their selective estrogen receptor modulator (SERM) activity. Using breast cancer cell lines as a model of estrogen-dependent proliferation and a stably ER-expressing PC12 cell line as a model of neuronal differentiating cells, we studied the SERM activity of major dietary compounds, such as apigenin, liquiritigenin, daidzein, genistein, coumestrol, resveratrol and zearalenone. The ability of these compounds to induce ER-transactivation and breast cancer cell proliferation and enhance Nerve Growth Factor (NGF) -induced neuritogenesis was assessed. Surprisingly, although all compounds were able to activate the ER through an estrogen responsive element reporter gene, they showed differential activity toward proliferation or differentiation. Apigenin and resveratrol showed a partial or no proliferative effect on breast cancer cells but fully contributed to the neuritogenesis effect of NGF. However, daidzein and zearalenone showed full effects on cellular proliferation but did not induce cellular differentiation. In summary, our results suggest that the therapeutic potential of phytoestrogens can diverge depending on the molecule and the phenotype considered. Hence, apigenin and resveratrol might be used in the development of therapeutics for breast cancer and brain diseases.
Asunto(s)
Neoplasias de las Glándulas Suprarrenales/tratamiento farmacológico , Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Dieta , Neurogénesis/efectos de los fármacos , Feocromocitoma/tratamiento farmacológico , Fitoestrógenos/farmacología , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Neoplasias de las Glándulas Suprarrenales/genética , Neoplasias de las Glándulas Suprarrenales/metabolismo , Neoplasias de las Glándulas Suprarrenales/patología , Animales , Apigenina/farmacología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Relación Dosis-Respuesta a Droga , Receptor alfa de Estrógeno/efectos de los fármacos , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Isoflavonas/farmacología , Células MCF-7 , Proteínas del Tejido Nervioso/metabolismo , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Neuritas/patología , Células PC12 , Feocromocitoma/genética , Feocromocitoma/metabolismo , Feocromocitoma/patología , Ratas , Elementos de Respuesta , Resveratrol , Estilbenos/farmacología , Transcripción Genética/efectos de los fármacos , Transfección , Zearalenona/farmacologíaRESUMEN
Chemotherapy-induced peripheral neuropathy (CIPN) is a major, dose-limiting adverse effect experienced by cancer patients. Advancements in mechanism-based risk mitigation and effective treatments for CIPN can be aided by suitable in vitro assays. To this end, we developed a multiparametric morphology-centered rat dorsal root ganglion (DRG) assay. Morphologic alterations in subcellular structures of neurons and non-neurons were analyzed with an automated microscopy system. Stains for NeuN (a neuron-specific nuclear protein) and Tuj-1 (ß-III tubulin) were used to identify neuronal cell nuclei and neuronal cell bodies/neurites, respectively. Vimentin staining (a component of Schwann cell intermediate filaments) was used to label non-neuronal supporting cells. Nuclei that stained with DAPI, but lacked NeuN represented non-neuronal cells. Images were analyzed following 24 h of continuous exposure to CIPN-inducing agents and 72 h after drug removal to provide a dynamic measure of recovery from initial drug effects. Treatment with bortezomib, cisplatin, eribulin, paclitaxel or vincristine induced a dose-dependent loss of neurite/process areas, mimicking the 'dying back' degeneration of axons, a histopathological hallmark of clinical CIPN in vivo. The IC50 for neurite loss was within 3-fold of the maximal clinical exposure (Cmax) for all five CIPN-inducing drugs, but was >4- or ≥ 28-fold of the Cmax for 2 non-CIPN-inducing agents. Compound-specific effects, eg, neurite fragmentation by cisplatin or bortezomib and enlarged neuronal cell bodies by paclitaxel, were also observed. Collectively, these results support the use of a quantitative, morphologic evaluation and a DRG cell culture model to inform risk and examine mechanisms of CIPN.
Asunto(s)
Antineoplásicos/efectos adversos , Ganglios Espinales/efectos de los fármacos , Neuronas/efectos de los fármacos , Animales , Biomarcadores/metabolismo , Cuerpo Celular/efectos de los fármacos , Cuerpo Celular/metabolismo , Cuerpo Celular/patología , Forma del Núcleo Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Evaluación Preclínica de Medicamentos/métodos , Electroforesis Capilar , Técnica del Anticuerpo Fluorescente , Ganglios Espinales/metabolismo , Ganglios Espinales/patología , Procesamiento de Imagen Asistido por Computador , Cinética , Peso Molecular , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Neuritas/patología , Neuronas/metabolismo , Neuronas/patología , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/metabolismo , Síndromes de Neurotoxicidad/patología , Forma de los Orgánulos/efectos de los fármacos , Tamaño de los Orgánulos/efectos de los fármacos , Enfermedades del Sistema Nervioso Periférico/etiología , Enfermedades del Sistema Nervioso Periférico/metabolismo , Enfermedades del Sistema Nervioso Periférico/patología , RatasRESUMEN
Alzheimer's disease (AD) is the most common cause of dementia; however, available treatments have had limited success. Therefore AD patients are in tremendous need of new pharmacological approaches that may delay or slow the progression of the disease. In addition to the classical neuropathological features, immunological and inflammatory processes are also involved in AD pathogenesis. Naturally occurring compounds, such as Mangifera indica Linn (MGF) extracts have previously been shown to significantly reduce peripheral inflammatory processes. In order to explore the role of MGF in AD central pathology, we have orally treated APP/PS1 mice for 22 weeks. While MGF did not affect amyloid pathology, tau hyperphosphorylation was significantly reduced in the cortex and hippocampus. Also, inflammatory processes, measured by microglia and astrocyte burdens, were diminished in MGF-treated mice. Moreover, neuronal morphological alterations, such as abnormal neurite curvature and dystrophies, highly increased in APP/PS1 mice, were significantly ameliorated by long-term MGF treatment. Reduction of all these pathological features were accompanied by compelling improvements of episodic and spatial memory in APP/PS1 mice treated with MGF. Altogether our data suggest that MGF may provide a useful tool to target different aspects of AD pathology and could lead to more effective future therapeutic or preventive strategies.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/patología , Extractos Vegetales/uso terapéutico , Presenilina-1/metabolismo , Xantonas/uso terapéutico , Enfermedad de Alzheimer/complicaciones , Amiloide/metabolismo , Animales , Trastornos del Conocimiento/complicaciones , Inflamación/complicaciones , Inflamación/tratamiento farmacológico , Inflamación/patología , Mangifera , Ratones , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Neuritas/patología , Extractos Vegetales/farmacología , Xantonas/farmacología , Proteínas tau/metabolismoRESUMEN
In Parkinson's disease (PD), pathological microstructural changes occur and such changes might be detected using diffusion magnetic resonance imaging (dMRI). However, it is unclear whether dMRI improves PD diagnosis or helps differentiating between phenotypes, such as postural instability gait difficulty (PIGD) and tremor dominant (TD) PD. We included 105 patients with PD and 44 healthy controls (HC), all of whom underwent dMRI as part of the prospective Swedish BioFINDER study. Diffusion kurtosis imaging (DKI) and neurite density imaging (NDI) analyses were performed using regions of interest in the basal ganglia, the thalamus, the pons and the midbrain as well as tractography of selected white matter tracts. In the putamen, the PD group showed increased mean diffusivity (MD) (p = .003), decreased fractional anisotropy (FA) (p = .001) and decreased mean kurtosis (MK), compared to HC (p = .024). High MD and a low MK in the putamen were associated with more severe motor and cognitive symptomatology (p < .05). Also, patients with PIGD exhibited increased MD in the putamen compared to the TD patients (p = .009). In the thalamus, MD was increased (p = .001) and FA was decreased (p = .032) in PD compared to HC. Increased MD and decreased FA correlated negatively with motor speed and balance (p < .05). In the superior longitudinal fasciculus (SLF), MD (p = .019) and fiso were increased in PD compared to HC (p = .03). These changes correlated negatively with motor speed (p < .002) and balance (p < .037). However, most of the observed changes in PD were also present in cases with either multiple system atrophy (n = 11) or progressive supranuclear palsy (n = 10). In conclusion, PD patients exhibit microstructural changes in the putamen, the thalamus, and the SLF, which are associated with worse disease severity. However, the dMRI changes are not sufficiently specific to improve the diagnostic work-up of PD. Longitudinal studies should evaluate whether dMRI measures can be used to track disease progression.
Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora/métodos , Sustancia Gris/diagnóstico por imagen , Neuritas/patología , Enfermedad de Parkinson/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Anciano , Estudios de Casos y Controles , Femenino , Sustancia Gris/patología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/patología , Estudios Prospectivos , Putamen/diagnóstico por imagen , Putamen/patología , Parálisis Supranuclear Progresiva/patología , Suecia , Tálamo/diagnóstico por imagen , Tálamo/patología , Sustancia Blanca/patologíaRESUMEN
Neuronal ceroid lipofuscinoses (NCL) are the most commonly inherited progressive encephalopathies of childhood. Pathologically, they are characterized by endolysosomal storage with different ultrastructural features and biochemical compositions. The molecular mechanisms causing progressive neurodegeneration and common molecular pathways linking expression of different NCL genes are largely unknown. We analyzed proteome alterations in the brains of a mouse model of human infantile CLN1 disease-palmitoyl-protein thioesterase 1 (Ppt1) gene knockout and its wild-type age-matched counterpart at different stages: pre-symptomatic, symptomatic and advanced. For this purpose, we utilized a combination of laser capture microdissection-based quantitative liquid chromatography tandem mass spectrometry (MS) and matrix-assisted laser desorption/ionization time-of-flight MS imaging to quantify/visualize the changes in protein expression in disease-affected brain thalamus and cerebral cortex tissue slices, respectively. Proteomic profiling of the pre-symptomatic stage thalamus revealed alterations mostly in metabolic processes and inhibition of various neuronal functions, i.e., neuritogenesis. Down-regulation in dynamics associated with growth of plasma projections and cellular protrusions was further corroborated by findings from RNA sequencing of CLN1 patients' fibroblasts. Changes detected at the symptomatic stage included: mitochondrial functions, synaptic vesicle transport, myelin proteome and signaling cascades, such as RhoA signaling. Considerable dysregulation of processes related to mitochondrial cell death, RhoA/Huntington's disease signaling and myelin sheath breakdown were observed at the advanced stage of the disease. The identified changes in protein levels were further substantiated by bioinformatics and network approaches, immunohistochemistry on brain tissues and literature knowledge, thus identifying various functional modules affected in the CLN1 childhood encephalopathy.
Asunto(s)
Corteza Cerebral/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Lipofuscinosis Ceroideas Neuronales/metabolismo , Proteómica , Tálamo/metabolismo , Animales , Células Cultivadas , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Fibroblastos/metabolismo , Perfilación de la Expresión Génica , Humanos , Captura por Microdisección con Láser , Masculino , Ratones , Mitocondrias , Modelos Neurológicos , Vaina de Mielina/patología , Proteínas del Tejido Nervioso/genética , Neuritas/patología , Lipofuscinosis Ceroideas Neuronales/genética , Lipofuscinosis Ceroideas Neuronales/patología , Lipofuscinosis Ceroideas Neuronales/fisiopatología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Tálamo/patología , Tálamo/fisiopatología , Tioléster Hidrolasas/deficiencia , Tioléster Hidrolasas/genéticaRESUMEN
Neurodegenerative diseases are frequently associated with the loss of synapses and neurons. Senegenin, extracted from the Chinese herb Polygala tenuifolia Willd, was previously found to promote neurite outgrowth and neuronal survival in primary cultured rat cortical neurons. The aim of the present study was to investigate the underlying mechanisms of senegenin-induced neurotrophic effects on rat cortical neurons. Primary cortical rat neurons were treated with various pharmacological antagonists and with or without senegenin, and subjected to MTT and western blot analysis to explore the effects of senegenin on cell survival as well as the activation of signaling pathways. Neurite outgrowth and neuronal survival induced by senegenin were significantly inhibited by A2A receptor antagonist ZM241385 and specific phosphoinositide-3 kinase (PI3K) inhibitor LY294002, but not by tropomyosin receptor kinase A receptor inhibitor K252a, mitogen-activated protein kinase kinase inhibitor PD98059 or protein kinase C inhibitor GÖ6976. Furthermore, senegenin enhanced the phosphorylation of Akt, which was blocked by LY294002. The present study revealed that the PI3K/Akt signaling pathway may be involved in the neurotrophic effects of senegenin.
Asunto(s)
Medicamentos Herbarios Chinos/administración & dosificación , Enfermedades Neurodegenerativas/tratamiento farmacológico , Neuronas/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/biosíntesis , Proteínas Proto-Oncogénicas c-akt/biosíntesis , Animales , Supervivencia Celular/efectos de los fármacos , Cromonas/administración & dosificación , Medicamentos Herbarios Chinos/química , Humanos , Morfolinas/administración & dosificación , Neuritas/efectos de los fármacos , Neuritas/patología , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/patología , Neuronas/patología , Fosfatidilinositol 3-Quinasas/genética , Polygala/química , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-akt/genética , Ratas , Transducción de Señal/efectos de los fármacos , Triazinas/administración & dosificación , Triazoles/administración & dosificaciónRESUMEN
Insufficient production of neurotrophic factors is implicated in the pathogenesis of various neurodegenerative disorders. The aim of the present study was to evaluate the potential of N-propargyl caffeate amide (PACA) to enhance nerve growth factor (NGF)-induced neurite outgrowth and the underlying mechanisms. We discovered that PACA not only potentiated NGF-induced neurite outgrowth but also attenuated 6-hydroxydopamine (6-OHDA) neurotoxicity in dopaminergic PC12 cells and primary rat midbrain neurons. To identify the PACA-binding proteins, we introduced a biotin tag to the covalent PACA-protein adducts via "click chemistry" alkyne-azido cycloaddition. As a result, kelch-like ECH-associated protein 1 (Keap1) was isolated as the predominant protein from PACA treated PC12 cells. We demonstrated that the formation of PACA-Keap1 conjugates induced the nuclear translocation of transcription factor Nrf2 and the expression of antioxidant heme oxygenase-1 (HO-1). Importantly, specific HO-1 inhibitor SnPP diminished the neuroprotective and neuritogenic activities of PACA. Moreover, PACA attenuated 6-OHDA-induced production of neurotoxic reactive oxygen species and reactive nitrogen species. PACA also preserved mitochondrial membrane integrity and enhanced the cellular resistance against 6-OHDA neurotoxicity. These results suggest that PACA may exhibit neuroprotective and neuritogenic activities via activating the Nrf2/HO-1 antioxidant pathway.
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Ácidos Cafeicos/farmacología , Hemo Oxigenasa (Desciclizante)/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Neuritas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Transporte Activo de Núcleo Celular/efectos de los fármacos , Transporte Activo de Núcleo Celular/fisiología , Animales , Ácidos Cafeicos/síntesis química , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Núcleo Celular/patología , Dopamina/metabolismo , Evaluación Preclínica de Medicamentos , Hemo Oxigenasa (Desciclizante)/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/fisiología , Mesencéfalo/efectos de los fármacos , Mesencéfalo/patología , Mesencéfalo/fisiopatología , Neuritas/patología , Neuritas/fisiología , Neuronas/efectos de los fármacos , Neuronas/patología , Neuronas/fisiología , Fármacos Neuroprotectores/síntesis química , Óxido Nítrico/metabolismo , Oxidopamina/toxicidad , Células PC12 , Ratas , Superóxidos/metabolismoRESUMEN
The effect of a 645 nm Light Emitting Diode (LED) light irradiation on the neurite growth velocity of adult Dorsal Root Ganglion (DRG) neurons with peripheral axon injury 4-10 days before plating and without previous injury was investigated. The real amount of light reaching the neurons was calculated by taking into account the optical characteristics of the light source and of media in the light path. The knowledge of these parameters is essential to be able to compare results of the literature and a way to reduce inconsistencies. We found that 4 min irradiation of a mean irradiance of 11.3 mW/cm(2) (corresponding to an actual irradiance reaching the neurons of 83 mW/cm(2)) induced a 1.6-fold neurite growth acceleration on non-injured neurons and on axotomized neurons. Although the axotomized neurons were naturally already in a rapid regeneration process, an enhancement was found to occur while irradiating with the LED light, which may be promising for therapy applications. Dorsal Root Ganglion neurons (A) without previous injury and (B) subjected to a conditioning injury.
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Ganglios Espinales/efectos de la radiación , Terapia por Luz de Baja Intensidad/métodos , Neuritas/efectos de la radiación , Nervio Ciático/lesiones , Células Receptoras Sensoriales/efectos de la radiación , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Ganglios Espinales/patología , Ganglios Espinales/fisiopatología , Terapia por Luz de Baja Intensidad/instrumentación , Vértebras Lumbares , Ratones , Microscopía , Neuritas/patología , Neuritas/fisiología , Distribución Aleatoria , Células Receptoras Sensoriales/patología , Células Receptoras Sensoriales/fisiología , Análisis Espectral , Grabación en VideoRESUMEN
Parkinson's disease (PD) is the second most common neurodegenerative disease. Much data has linked the etiology of PD to a variety of environmental factors. The majority of cases are thought to arise from a combination of genetic susceptibility and environmental factors. Chronic exposures to dietary factors, including meat, have been identified as potential risk factors. Although heterocyclic amines that are produced during high-temperature meat cooking are known to be carcinogenic, their effect on the nervous system has yet to be studied in depth. In this study, we investigated neurotoxic effects of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a highly abundant heterocyclic amine in cooked meat, in vitro. We tested toxicity of PhIP and the two major phase I metabolites, N-OH-PhIP and 4'-OH-PhIP, using primary mesencephalic cultures from rat embryos. This culture system contains both dopaminergic and nondopaminergic neurons, which allows specificity of neurotoxicity to be readily examined. We find that exposure to PhIP or N-OH-PhIP is selectively toxic to dopaminergic neurons in primary cultures, resulting in a decreased percentage of dopaminergic neurons. Neurite length is decreased in surviving dopaminergic neurons. Exposure to 4'-OH-PhIP did not produce significant neurotoxicity. PhIP treatment also increased formation of oxidative damage markers, 4-hydroxy-2-nonenal (HNE) and 3-nitrotyrosine in dopaminergic neurons. Pretreatment with N-acetylcysteine was protective. Finally, treatment with blueberry extract, a dietary factor with known antioxidant and other protective mechanisms, prevented PhIP-induced toxicity. Collectively, our study suggests, for the first time, that PhIP is selectively toxic to dopaminergic neurons likely through inducing oxidative stress.
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Neuronas Dopaminérgicas/efectos de los fármacos , Imidazoles/toxicidad , Animales , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Unión Competitiva , Arándanos Azules (Planta)/química , Supervivencia Celular/efectos de los fármacos , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Imidazoles/metabolismo , Mesencéfalo/citología , Mesencéfalo/embriología , Mesencéfalo/metabolismo , Neuritas/efectos de los fármacos , Neuritas/patología , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/metabolismo , Síndromes de Neurotoxicidad/patología , Síndromes de Neurotoxicidad/prevención & control , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Cultivo Primario de Células , Ratas Sprague-DawleyRESUMEN
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder in which motor neuron (MN) loss in the spinal cord leads to progressive paralysis and death. Cytosolic aggregations in ALS MNs are composed of Tar DNA-binding protein-43 (TDP-43). Genetic analysis has identified more than twenty mutations of TDP-43 in ALS cases. Although accumulating evidence provides several hypotheses of disease mechanism, it is still needed to discover effective cure for ALS. We aimed to reveal cellular phenotypes in ALS MNs for identifying a drug-screening target for ALS using patient-specific induced pluripotent stem cells (iPSCs). To generate patient-specific iPSCs, dermal fibroblasts were obtained by biopsy from ALS patients carrying mutant TDP-43. The fibroblasts were reprogrammed by retrovirus or episomal vectors. Disease-specific iPSCs were differentiated into MNs expressing HB9 and SMI-32. Despite short culture period, ALS MNs recapitulated several disease phenotypes including detergent-insoluble TDP-43, shortened neurites and cellular vulnerability that observed in patient and animal models. Anacardic acid treatment reverted those phenotypes. Disease-specific iPSCs might provide a first step for drug-screening platform for ALS using patient-specific iPSCs.
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Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Evaluación Preclínica de Medicamentos , Células Madre Pluripotentes Inducidas/citología , Neuronas Motoras , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Ácidos Anacárdicos/farmacología , Ácidos Anacárdicos/uso terapéutico , Animales , Diferenciación Celular , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Descubrimiento de Drogas , Humanos , Terapia Molecular Dirigida , Neuronas Motoras/citología , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , Mutación , Neuritas/patología , Estrés OxidativoRESUMEN
BACKGROUND: In order to gain insight into neuroprotective effects of ECa 233, a standardized extract of Centella asiatica, previously demonstrated in animal models of memory impairment induced by transient global ischemia or intracerebroventricular injection of ß-amyloid, the effect of ECa 233 on neurite outgrowth of human IMR-32 neuroblastoma cell line was investigated. METHODS: Cells were seeded and incubated with various concentrations of ECa 233. Morphometric analysis was carried out by a measurement of the longest neurite growth of cells at 24 and 48 h. Contributing signaling pathways possibly involved were subsequently elucidated by western blot analysis. RESULTS: While ECa 233 had only limited effects on cell viability, it significantly enhanced neurite outgrowth of IMR-32 cells at the concentrations of 1-100 µg/ml. Western blot analysis revealed that ECa 233 significantly upregulated the level of activated ERK1/2 and Akt of the treated cells suggesting their involvement in the neuritogenic effect observed, which was subsequently verified by the finding that an addition of their respective inhibitors could reverse the effect of ECa 233 on these cells. CONCLUSIONS: The present study clearly demonstrated neurite outgrowth promoting activity of ECa 233. ERK1/2 and Akt signaling pathways seemed to account for the neurotrophic effect observed. In conjunction with in vivo neuroprotective effect of ECa 233 previously reported, the results obtained support further development of ECa 233 for clinical use in neuronal injury or neurodegenerative diseases.
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Centella/química , Neuritas/efectos de los fármacos , Neuroblastoma/patología , Fármacos Neuroprotectores/farmacología , Extractos Vegetales/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neuritas/enzimología , Neuritas/patología , Neuroblastoma/enzimología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacosRESUMEN
SCOPE: To elucidate the morphological and biochemical in vitro effects exerted by caffeine, taurine, and guarana, alone or in combination, since they are major components in energy drinks (EDs). METHODS AND RESULTS: On human neuronal SH-SY5Y cells, caffeine (0.125-2 mg/mL), taurine (1-16 mg/mL), and guarana (3.125-50 mg/mL) showed concentration-dependent nonenzymatic antioxidant potential, decreased the basal levels of free radical generation, and reduced both superoxide dismutase (SOD) and catalase (CAT) activities, especially when combined together. However, guarana-treated cells developed signs of neurite degeneration in the form of swellings at various segments in a beaded or pearl chain-like appearance and fragmentation of such neurites at concentrations ranging from 12.5 to 50 mg/mL. Swellings, but not neuritic fragmentation, were detected when cells were treated with 0.5 mg/mL (or higher doses) of caffeine, concentrations that are present in EDs. Cells treated with guarana also showed qualitative signs of apoptosis, including membrane blebbing, cell shrinkage, and cleaved caspase-3 positivity. Flow cytometric analysis confirmed that cells treated with 12.5-50 mg/mL of guarana and its combinations with caffeine and/or taurine underwent apoptosis. CONCLUSION: Excessive removal of intracellular reactive oxygen species, to nonphysiological levels (or "antioxidative stress"), could be a cause of in vitro toxicity induced by these drugs.
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Cafeína/farmacología , Bebidas Energéticas , Neuronas/metabolismo , Neuronas/patología , Paullinia/química , Especies Reactivas de Oxígeno/metabolismo , Taurina/farmacología , Antioxidantes/metabolismo , Catalasa/metabolismo , Recuento de Células , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Forma de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Depuradores de Radicales Libres/metabolismo , Humanos , Radical Hidroxilo/metabolismo , Espacio Intracelular/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Modelos Biológicos , Degeneración Nerviosa/patología , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Neuritas/patología , Neuronas/efectos de los fármacos , Neuronas/enzimología , Óxido Nítrico/metabolismo , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/metabolismoRESUMEN
Global hypoxia-ischemia interrupts oxygen delivery and blood flow to the entire brain. Previous studies of global brain hypoxia-ischemia have primarily focused on injury to the cerebral cortex and to the hippocampus. Susceptible neuronal populations also include inhibitory neurons in the thalamic reticular nucleus. We therefore investigated the impact of global brain hypoxia-ischemia on the thalamic circuit function in the somatosensory system of young rats. We used single neuron recordings and controlled whisker deflections to examine responses of thalamocortical neurons to sensory stimulation in rat survivors of 9 min of asphyxial cardiac arrest incurred on postnatal day 17. We found that 48-72 h after cardiac arrest, thalamocortical neurons demonstrate significantly elevated firing rates both during spontaneous activity and in response to whisker deflections. The elevated evoked firing rates persist for at least 6-8 weeks after injury. Despite the overall increase in firing, by 6 weeks, thalamocortical neurons display degraded receptive fields, with decreased responses to adjacent whiskers. Nine minutes of asphyxial cardiac arrest was associated with extensive degeneration of neurites in the somatosensory nucleus as well as activation of microglia in the reticular nucleus. Global brain hypoxia-ischemia during cardiac arrest has a long-term impact on processing and transfer of sensory information by thalamic circuitry. Thalamic circuitry and normalization of its function may represent a distinct therapeutic target after cardiac arrest.
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Asfixia/fisiopatología , Paro Cardíaco/fisiopatología , Corteza Somatosensorial/fisiopatología , Tálamo/lesiones , Tálamo/fisiopatología , Potenciales de Acción/fisiología , Factores de Edad , Animales , Masculino , Vías Nerviosas/crecimiento & desarrollo , Vías Nerviosas/fisiopatología , Neuritas/patología , Ratas , Ratas Sprague-Dawley , Corteza Somatosensorial/crecimiento & desarrollo , Tálamo/crecimiento & desarrollo , Vibrisas/fisiologíaRESUMEN
Selenoprotein P (Sepp1) is an important protein involved in selenium (Se) transport and homeostasis. Severe neurologic dysfunction develops in Sepp1 null mice (Sepp1(-/-)) fed a selenium-deficient diet. Sepp1(-/-) mice fed a selenium-deficient diet have extensive degeneration of the brainstem and thalamus, and even when supplemented with selenium exhibit subtle learning deficits and altered basal synaptic transmission and short-term plasticity in the CA1 region of the hippocampus. The goal of this study was to delineate the regional progression of neurodegeneration in the brain, determine the extent of neuronal cell death, and evaluate neurite structural changes within the hippocampus of Sepp1(-/-) mice. Whole brain serial sections of wild-type and Sepp1(-/-) mice maintained on selenium-deficient or supplemented diets over the course of 12 days from weaning were evaluated with amino cupric silver neurodegeneration stain. The neurodegeneration was present in all regions upon weaning and progressed over 12 days in Sepp1(-/-) mice fed selenium-deficient diet, except in the medial forebrain bundle and somatosensory cortex where the neurodegeneration developed post-weaning. The neurodegeneration was predominantly axonal, however the somatosensory cortex and lateral striatum showed silver-stained neurons. Morphologic analysis of the hippocampus revealed decreased dendritic length and spine density, suggesting that loss of Sepp1 also causes subtle changes in the brain that can contribute to functional deficits. These data illustrate that deletion of Sepp1, and presumably selenium deficiency in the brain, produce both neuronal and axonal degeneration as well as more moderate and potentially reversible neurite changes in the developing brain.