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INTRODUCTION: Neurological soft signs (NSS) are subtle non-localizing sensorimotor abnormalities initially reported as increased in primary headache patients. The aims of this study were confirming with full power NSS increased expression in migraine and, collaterally, determining if psychiatric traits or white matter lesions at brain imaging could influence this result. METHODS: Forty drug-free episodic migraine outpatients (MH) were recruited with 40 matched controls. NSS were determined by the 16-item Heidelberg scale; depression, anxiety and QoL by the HAM-D; the STAI-X1/X2; and the SF36, respectively. The Fazekas scale on brain MR studies was applied in n = 32 MH, unravelling deep white matter signal alterations (DWM). MH characteristics, including the headache disability inventory (HDI), were recorded. RESULTS: NSS were 46% increased in MH vs. controls (p = 0.0001). HAM-D and STAI-X1/X2 were increased in MH, while SF36 was unchanged, but they all failed to influence NSS, just as MH characteristics. NSS scores were increased in MH-DWM + (n = 11, + 85%) vs. MH-DWM - (n = 21, + 27%) vs. controls (p < 0.0001). NSS increased expression in MH was influenced by DWM, while psychiatric traits and headache characteristics failed to do so. DISCUSSION/CONCLUSIONS: NSS are increased in MH and probably not influenced by the affective status, possibly marking a dysfunction within the cerebellar-thalamic-prefrontal circuit that may deserve further attention from the prognostic point of view.
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Migraña sin Aura , Esquizofrenia , Cefalea , Humanos , Imagen por Resonancia Magnética , Examen Neurológico , Calidad de Vida , Esquizofrenia/patologíaRESUMEN
Autophagy is a degradative process playing an important role in removing misfolded or aggregated proteins, clearing damaged organelles, such as mitochondria and endoplasmic reticulum, as well as eliminating intracellular pathogens. The autophagic process is important for balancing sources of energy at critical developmental stages and in response to nutrient stress. Recently, autophagy has been involved in the pathophysiology of neurodegenerative diseases although its beneficial (pro-survival) or detrimental (pro-death) role remains controversial. In the present review, we discuss the role of autophagy following intoxication with trimethyltin (TMT), an organotin compound that induces severe hippocampal neurodegeneration associated with astrocyte and microglia activation. TMT is considered a useful tool to study the molecular mechanisms occurring in human neurodegenerative diseases such as Alzheimer's disease and temporal lobe epilepsy. This is also relevant in the field of environmental safety, since organotin compounds are used as heat stabilizers in polyvinyl chloride polymers, industrial and agricultural biocides, and as industrial chemical catalysts.
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Enfermedades Neurodegenerativas , Compuestos de Trimetilestaño , Autofagia , Hipocampo , Humanos , Enfermedades Neurodegenerativas/inducido químicamente , Compuestos de Trimetilestaño/toxicidadRESUMEN
Protease-activated receptor 1 (PAR1) is a cell surface receptor, which belongs to a family of G protein-coupled receptors and signals in response to multiple extracellular proteases. PAR1 is widely distributed in mammalian cells and tissues, including human glial cells. Within this context, PAR1 may participate to various activities promoted by glial cells. In fact, glia does not represent merely a glue in the nervous system but affects significantly various neuronal functions and activities being also significantly involved in the pathophysiology of various nervous system disorders. In this review, we summarize the current understanding of PAR1 expression and functions within glial cells both in the central and peripheral nervous system.
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Sistema Nervioso Central/metabolismo , Neuroglía/metabolismo , Sistema Nervioso Periférico/metabolismo , Receptor PAR-1/metabolismo , Animales , Astrocitos/metabolismo , Humanos , Receptor PAR-1/genética , Células de Schwann/metabolismoRESUMEN
Protease-activated receptor-1 (PAR1) is the prototypic member of a family of four G-protein-coupled receptors that signal in response to extracellular proteases. In the peripheral nervous system, the expression and/or the role of PARs are still poorly investigated. High PAR1 mRNA expression was found in the rat dorsal root ganglia and the signal intensity of PAR1 mRNA increased in response to sciatic nerve transection. In the sciatic nerve, functional PAR1 receptor was reported at the level of non-compacted Schwann cell myelin microvilli of the nodes of Ranvier. Schwann cells are the principal population of glial cells of the peripheral nervous system which myelinate axons playing an important role during axonal regeneration and remyelination. The present study was undertaken in order to determine if the activation of PAR1 affects the neurotrophic properties of Schwann cells. Our results suggest that the stimulation of PAR1 could potentiate the Schwann cell ability to favour nerve regeneration. In fact, the conditioned medium obtained from Schwann cell cultures challenged with a specific PAR1 activating peptide (PAR1 AP) displays increased neuroprotective and neurotrophic properties with respect to the culture medium from untreated Schwann cells. The proteomic analysis of secreted proteins in untreated and PAR1 AP-treated Schwann cells allowed the identification of factors differentially expressed in the two samples. Some of them (such as macrophage migration inhibitory factor, matrix metalloproteinase-2, decorin, syndecan 4, complement C1r subcomponent, angiogenic factor with G patch and FHA domains 1) appear to be transcriptionally regulated after PAR1 AP treatment as shown by RT-PCR.
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Factores de Crecimiento Nervioso/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Células de Schwann/metabolismo , Proteínas Angiogénicas/genética , Proteínas Angiogénicas/metabolismo , Animales , Células Cultivadas , Complemento C1q/genética , Complemento C1q/metabolismo , Complemento C1r/genética , Complemento C1r/metabolismo , Medios de Cultivo Condicionados/farmacología , Decorina/genética , Decorina/metabolismo , Femenino , Oxidorreductasas Intramoleculares/genética , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/genética , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Factores de Crecimiento Nervioso/farmacología , Regeneración Nerviosa/efectos de los fármacos , Células PC12 , Ratas , Ratas Wistar , Nervio Ciático/citología , Nervio Ciático/metabolismo , Nervio Ciático/fisiología , Sindecano-4/genética , Sindecano-4/metabolismoRESUMEN
In the responsiveness of microglia to toxic stimuli, plasma membrane proteins play a key role. In this study we treated with a synthetic beta amyloid peptide murine microglial cells metabolically differently labelled with stable isotope amino acids (SILAC). The plasma membrane was selectively enriched by a multi-stage aqueous two-phase partition system. We were able to identify by 1D-LC-MS/MS analyses 1577 proteins, most of them are plasma membrane proteins according to the Gene Ontology annotation. An unchanged level of amyloid receptors in this data set suggests that microglia preserve their responsiveness capability to the environment even after 24-h challenge with amyloid peptides. On the other hand, 14 proteins were observed to change their plasma membrane abundance to a statistically significant extent. Among these, we proposed as reliable biomarkers of the inflammatory microglia phenotype in AD damaged tissues MAP/microtubule affinity-regulating kinase 3 (MARK3), Interferon-induced transmembrane protein 3 (IFITM3), Annexins A5 and A7 (ANXA5, ANXA7) and Neuropilin-1 (NRP1), all proteins known to be involved in the inflammation processes and in microtubule network assembly rate.
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Péptidos beta-Amiloides/farmacología , Membrana Celular/metabolismo , Proteínas de la Membrana/metabolismo , Microglía/metabolismo , Proteómica/métodos , Animales , Línea Celular , Membrana Celular/efectos de los fármacos , Marcaje Isotópico , Ratones , Microglía/efectos de los fármacos , RatasRESUMEN
Trimethyltin (TMT) is a highly toxic molecule present as an environmental contaminant causing neurodegeneration particularly of the limbic system both in humans and in rodents. We recently described the occurrence of impairment in the late stages of autophagy in TMT-intoxicated astrocytes. Here we show that similarly to astrocytes also in microglia, TMT induces the precocious block of autophagy indicated by the accumulation of the autophagosome marker, microtubule associated protein light chain 3. Consistent with autophagy impairment we observe in TMT-treated microglia the accumulation of p62/SQSTM1, a protein specifically degraded through this pathway. Lithium has been proved effective in limiting neurodegenerations and, in particular, in ameliorating symptoms of TMT intoxication in rodents. In our in vitro model, lithium displays a pro-survival and anti-inflammatory action reducing both cell death and the proinflammatory response of TMT-treated microglia. In particular, lithium exerts these activities without reducing TMT-induced accumulation of light chain 3 protein. In fact, the autophagic block imposed by TMT is unaffected by lithium administration. These results are of interest as defects in the execution of autophagy are frequently observed in neurodegenerative diseases and lithium is considered a promising therapeutic agent for these pathologies. Thus, it is relevant that this cation can still maintain its pro-survival and anti-inflammatory role in conditions of autophagy block. Copyright © 2016 John Wiley & Sons, Ltd.
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Autofagia/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Litio/farmacología , Microglía , Fármacos Neuroprotectores/farmacología , Compuestos de Trimetilestaño/toxicidad , Animales , Animales Recién Nacidos , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Interleucina-10/inmunología , Masculino , Microglía/efectos de los fármacos , Microglía/inmunología , Microglía/patología , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
Dupuytren's contracture (DC) is a benign fibro-proliferative disease of the hand causing fibrotic nodules and fascial cords which determine debilitating contracture and deformities of fingers and hands. The present study was designed to characterize pro-inflammatory cytokines and growth factors involved in the pathogenesis, progression and recurrence of this disease, in order to find novel targets for alternative therapies and strategies in controlling DC. The expression of pro-inflammatory cytokines and of growth factors was detected by immunohistochemistry in fibrotic nodules and normal palmar fascia resected respectively from patients affected by DC and carpal tunnel syndrome (CTS; as negative controls). Reverse transcription (RT)-PCR analysis and immunofluorescence were performed to quantify the expression of transforming growth factor (TGF)-ß1, interleukin (IL)-1ß and vascular endothelial growth factor (VEGF) by primary cultures of myofibroblasts and fibroblasts isolated from Dupuytren's nodules. Histological analysis showed high cellularity and high proliferation rate in Dupuytren's tissue, together with the presence of myofibroblastic isotypes; immunohistochemical staining for macrophages was completely negative. In addition, a strong expression of TGF-ß1, IL-1ß and VEGF was evident in the extracellular matrix and in the cytoplasm of fibroblasts and myofibroblasts in Dupuytren's nodular tissues, as compared with control tissues. These results were confirmed by RT-PCR and by immunofluorescence in pathological and normal primary cell cultures. These preliminary observations suggest that TGF-ß1, IL-1ß and VEGF may be considered potential therapeutic targets in the treatment of Dupuytren's disease (DD).
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Contractura de Dupuytren/etiología , Interleucina-1beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Estudios de Casos y Controles , Células Cultivadas , Contractura de Dupuytren/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Neurodegenerative diseases (NDs) include a large variety of disorders that affects specific areas of the centralnervous system, leading to psychiatric and movement pathologies. A common feature that characterizes thesedisorders is the neuronal formation and accumulation of misfolded protein aggregates that lead to cell death. Inparticular, different proteinaceous aggregates accumulate to trigger a variety of clinical manifestations: prionprotein (PrPSc) in prion diseases, ß-amyloid (Aß) in Alzheimer's disease (AD), α-synuclein in Parkinson's disease(PD), huntingtin in Huntington's disease (HD), superoxide dismutase and TDP-43 in amyotrophic lateral sclerosis(ALS), tau in tauopathies. Non-motor alterations also occur in several viscera, in particular the gastrointestinaltract. These often precede the onset of motor symptoms by several years. For this reason, dysautonomic changescan be predictive of NDs and their correct recognition is being assuming a remarkable importance. This peculiarfeature led more and more to the concept that neurodegeneration may initiate in the periphery and propagate retrogradelytowards the central nervous system in a prion-like manner. In recent years, a particular attention wasdedicated to the clinical assessment of autonomic disorders in patients affected by NDs. In this respect, experimentalanimal models have been developed to understand the neurobiology underlying these effects as well as toinvestigate autonomic changes in peripheral organs. This review summarizes experimental studies that have beencarried out to understand autonomic symptoms in NDs, with the purpose to provide appropriate tools for comprehensiveand integrated studies.
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The neurobiology of non-motor symptoms in Parkinson's disease (PD) reveals a number of unexpected areas which once were not recognized a priori as part of the neuropathology underlying PD. These areas may belong either to central nervous system or periphery. Among central areas major efforts in the last decade led to recognize a number of brain nuclei as part of the disease spreading or disease onset in PD patients. Unexpectedly recent evidence deriving from pathological studies in PD patients and corroborated by experimental models of PD provided clear evidence that the spinal cord is often recruited in PD pathology. Such an involvement is intriguing since the major degenerative disease of the spinal cord (amyotrophic lateral sclerosis) features the involvement of dopaminergic neurons of the substantia nigra pars compacta, while some environmental (parkinsonism, ALS, and dementia of Guam) and genetic (Kufor-Rakeb syndrome) diseases are known to be characterized by mixed degeneration of pyramidal and extrapyramidal regions. Thus, the clear-cut between degeneration of dopaminergic neurons in the substantia nigra and the loss of pyramidal motor system appears now more as a continuum of degeneration which converge in abnormal activity and cell pathology of motor neurons as a final common pathway. Among motor neurons, visceral efferent cells of the spinal cord are involved and provide a robust neurobiological findings which may justify a variety of non-motor autonomic symptoms which characterize PD. Neurodegeneration in the spinal cord extends to the dorsal horn of the grey matter posing an intriguing link between PD and sensory alterations. The present manuscript reviews the involvement of multiple regions of the spinal cord in PD and experimental parkinsonism in the attempt to provide both a neurobiological background to understand non motor symptoms and to provide the anatomical basis for disease spreading.
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Microglia-mediated inflammation in the central nervous system is a hallmark of the pathogenesis of several neurodegenerative diseases including Alzheimer's disease. Microglial cells activation follows the deposition of amyloid ß fibrils and it is generally considered a triggering factor in the early steps of the onset of Alzheimer's disease. Although the initial engagement of microglia seems to play a neuroprotective role, many lines of evidence indicate that a persistent activation with the production of proinflammatory molecules contributes to dismantle neuronal activity and to induce neuronal loss occurring in neurodegenerative diseases. To date, limited proteomic data are available on activated microglial cells in response to extracellular amyloidogenic peptides. In this study, murine microglial cells have been employed to investigate the effects of amyloid ß peptides in triggering microglial activation. The response was monitored at the proteome level through a two-dimensional gel electrophoresis-based approach. Results show only a limited number of differentially expressed proteins, among these a more acidic species of the cytosolic actin, and the 14-3-3ε protein, found significantly upregulated in Aß-activated cells. 14-3-3ε belongs to a regulatory protein family involved in important cellular processes, including those leading to neurodegenerative diseases, and thus its increased expression suggests a role of this protein in tuning microglia activation.
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Proteínas 14-3-3/metabolismo , Inflamación/metabolismo , Microglía/patología , Proteínas 14-3-3/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides , Proteínas Amiloidogénicas , Animales , Biomarcadores/metabolismo , Línea Celular Transformada , Inflamación/inducido químicamente , Ratones , Microglía/efectos de los fármacos , Microglía/metabolismo , Proteoma/genética , Proteoma/metabolismo , Regulación hacia ArribaRESUMEN
Acute medical complications often prevent patients with stroke from being transferred from stroke units to rehabilitation units, prolonging the occupation of hospital beds and delaying the start of intensive rehabilitation. This study defined incidence, timing, duration and risk factors of these complications during the acute phase of stroke. A retrospective case note review was made of hospital admissions of patients with stroke not associated with other disabling conditions, admitted to a stroke unit over 12 months and requiring rehabilitation for gait impairment. In this cohort, a search was made of hypertension, oxygen de-saturation, fever, and cardiac and pulmonary symptoms requiring medical intervention. Included were 135 patients. Hypertension was the most common complication (16.3%), followed by heart disease (14.8%), oxygen de-saturation (7.4%), fever (6.7%) and pulmonary disease (5.2%). Heart disease was the earliest and shortest complication. Most complications occurred during the first week. Except for hypertension, all complications resolved within 2 weeks.
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Accidente Cerebrovascular/complicaciones , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fiebre/complicaciones , Fiebre/epidemiología , Cardiopatías/complicaciones , Cardiopatías/epidemiología , Unidades Hospitalarias , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Hipoxia/complicaciones , Hipoxia/epidemiología , Enfermedades Pulmonares/complicaciones , Enfermedades Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Transferencia de Pacientes , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Rehabilitación de Accidente Cerebrovascular , Adulto JovenRESUMEN
In contrast with the brain and spinal cord, peripheral nerves possess a striking ability to regenerate after damage. This characteristic of the peripheral nervous system is mainly due to a specific population of glial cells, the Schwann cells. Schwann cells promptly activate after nerve injury, dedifferentiate assuming a repair phenotype, and assist axon regrowth. In general, tissue injury determines the release of a variety of proteases which, in parallel with the degradation of their specific targets, also activate plasma membrane receptors known as protease-activated receptors (PARs). PAR1, the prototypical member of the PAR family, is also known as thrombin receptor and is present at the Schwann cell plasma membrane. This receptor is emerging as a possible regulator of the pro-regenerative capacity of Schwann cells. Here, we summarize the most recent literature data describing the possible contribution of PAR1 and PAR1-activating proteases in regulating the regeneration of peripheral nerves.
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Células de Schwann , Animales , Axones , Ligandos , Neuroglía , Receptor PAR-1 , TrombinaRESUMEN
Thrombotic complications are common in COVID-19 patients, but cerebral venous system involvement, timing after infection, optimal treatment, and long-term outcome are uncertain. We report a case of massive cerebral venous thrombosis and concomitant internal iliac vein thrombosis occurring in the late phase of paucisymptomatic COVID-19 infection. Mild respiratory symptoms, without fever, started 3 weeks before headache and acute neurological deficits. The patient had silent hypoxemia and typical COVID-19 associated interstitial pneumonia. Brain CT scan showed a left parietal hypodense lesion with associated sulcal subarachnoid hemorrhage. CT cerebral venography showed a massive cerebral venous thrombosis involving the right transverse sinus, the right jugular bulb, the superior sagittal sinus, the straight sinus, the vein of Galen, and both internal cerebral veins. Abdominal CT scan showed no malignancy but revealed an asymptomatic right internal iliac vein thrombosis. Both cerebral venous thrombosis and pelvic vein thrombosis were effectively treated with unfractionated heparin started on the day of admission, then shifted to low molecular weight heparin, with a favorable clinical course. Nasopharyngel swab, repeated twice, tested negative for SARS-CoV-2. Serological tests confirmed SARS-CoV-2 infection. Our case supports active surveillance and prevention of thrombotic complications associated with COVID-19, which may affect both peripheral and cerebral venous system. Early initiation of unfractionated heparin may lead to good neurologic outcome.
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Signal transduction pathways, involved in cell cycle and activities, depend on various components including lipid signalling molecules, such as phosphoinositides and related enzymes. Many evidences support the hypothesis that inositol lipid cycle is involved in astrocytes activation during neurodegeneration. Previous studies investigated the pattern of expression of phosphoinositide-specific phospholipase C (PI-PLC) family isoforms in astrocytes, individuating in cultured neonatal rat astrocytes, supposed to be quiescent cells, the absence of some isoforms, accordingly to their well known tissue specificity. The same study was conducted in cultured rat astrocytoma C6 cells and designed a different pattern of expression of PI-PLCs in the neoplastic counterpart, accordingly to literature suggesting a PI signalling involvement in tumour progression. It is not clear the role of PI-PLC isoforms in inflammation; recent data demonstrate they are involved in cytokines production, with special regard to IL-6. PI-PLCs expression in LPS treated neonatal rat astrocytes performed by using RT-PCR, observed at 3, 6, 18 and 24 h intervals, expressed: PI-PLC beta1, beta4 and gamma1 in all intervals analysed; PI-PLC delta1 at 6, 18 and 24 h; PI-PLC delta3 at 6 h after treatment. PI-PLC beta3, delta4 and epsilon, present in untreated astrocytes, were not detected after LPS treatment. Immunocytochemical analysis, performed to visualize the sub-cellular distribution of the expressed isoforms, demonstrated different patterns of localisation at different times of exposure. These observations suggest that PI-PLCs expression and distribution may play a role in ongoing inflammation process of CNS.
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Astrocitos/efectos de los fármacos , Astrocitos/enzimología , Lipopolisacáridos/farmacología , Fosfoinositido Fosfolipasa C/genética , Fosfoinositido Fosfolipasa C/metabolismo , Animales , Animales Recién Nacidos , Astrocitos/citología , Células Cultivadas , Electroforesis en Gel de Agar , Técnica del Anticuerpo Fluorescente , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Isoenzimas/genética , Isoenzimas/metabolismo , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Phosphoinositide specific phospholipase C (PI-PLC) enzymes interfere with the metabolism of inositol phospholipids (PI), molecules involved in signal transduction, a complex process depending on various components. Many evidences support the hypothesis that, in the glia, isoforms of PI-PLC family display different expression and/or sub cellular distribution under non-physiological conditions such as the rat astrocytes activation during neurodegeneration, the tumoural progression of some neoplasms and the inflammatory cascade activation after lipopolysaccharide administration, even if their role remains not completely elucidated. Treatment of a cultured established glioma cell line (C6 rat astrocytoma cell line) induces a modification in the pattern of expression and of sub cellular distribution of PI-PLCs compared to untreated cells. Special attention require PI-PLC beta3 and PI-PLC gamma2 isoforms, whose expression and sub cellular localization significantly differ after U-73122 treatment. The meaning of these modifications is unclear, also because the use of this N-aminosteroid compound remains controversial, inasmuch it has further actions which might contribute to the global effect recorded on the treated cells.
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Astrocitoma/patología , Estrenos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Fosfoinositido Fosfolipasa C/metabolismo , Pirrolidinonas/farmacología , Fracciones Subcelulares/efectos de los fármacos , Animales , Astrocitoma/enzimología , Secuencia de Bases , Línea Celular Tumoral , Cartilla de ADN , Inmunohistoquímica , Microscopía Fluorescente , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Fracciones Subcelulares/enzimologíaRESUMEN
Neurotrophins (NTs) expression was assessed in malignant and non-malignant pleural effusions (inflammatory exudates and transudates). Enzyme-linked immunosorbent assay, in malignant exudates from small and non-small cell lung cancer (SCLC and NSCLC), detected nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3), and their levels are higher as compared with inflammatory and transudative effusions. By immunoblots, in cultured cancer cells coming from malignant pleural effusions, NTs and low- and high-affinity NT receptors were detected in a percentage of SCLC and NSCLC. Proliferation assay demonstrated that BDNF significantly increased cancer cell proliferation in vitro, on the contrary, NT-3 reduced cancer cell growth rate and NGF did not modify cell growth. Moreover, NGF protects cells from death during starvation. These effects are reverted by the addition of NT receptor antagonists. Cultured cancer cells injected into the lung of immunodeficient mice generate lung tumors expressing NTs and NT receptors. These findings suggest that NTs may be able to modulate cancer cell behavior and their growth.
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Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Neurotrofina 3/metabolismo , Derrame Pleural Maligno/metabolismo , Derrame Pleural/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Western Blotting , Factor Neurotrófico Derivado del Encéfalo/sangre , Factor Neurotrófico Derivado del Encéfalo/farmacología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Pulmón/patología , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad , Trasplante de Neoplasias , Factores de Crecimiento Nervioso/sangre , Factores de Crecimiento Nervioso/farmacología , Neurotrofina 3/sangre , Neurotrofina 3/farmacología , Derrame Pleural/genética , Derrame Pleural Maligno/genética , Receptor trkB/metabolismo , Transducción de Señal , Carcinoma Pulmonar de Células Pequeñas/metabolismo , Células Tumorales CultivadasRESUMEN
Schwann cells (SC) are characterized by a remarkable plasticity that enables them to promptly respond to nerve injury promoting axonal regeneration. In peripheral nerves after damage SC convert to a repair-promoting phenotype activating a sequence of supportive functions that drive myelin clearance, prevent neuronal death, and help axon growth and guidance. Regeneration of peripheral nerves after damage correlates inversely with thrombin levels. Thrombin is not only the key regulator of the coagulation cascade but also a protease with hormone-like activities that affects various cells of the central and peripheral nervous system mainly through the protease-activated receptor 1 (PAR1). Aim of the present study was to investigate if and how thrombin could affect the axon supportive functions of SC. In particular, our results show that the activation of PAR1 in rat SC cultures with low levels of thrombin or PAR1 agonist peptides induces the release of molecules, which favor neuronal survival and neurite elongation. Conversely, the stimulation of SC with high levels of thrombin or PAR1 agonist peptides drives an opposite effect inducing SC to release factors that inhibit the extension of neurites. Moreover, high levels of thrombin administered to sciatic nerve ex vivo explants induce a dramatic change in SC morphology causing disappearance of the Cajal bands, enlargement of the Schmidt-Lanterman incisures and calcium-mediated demyelination of the paranodes. Our results indicate thrombin as a novel modulator of SC plasticity potentially able to favor or inhibit SC pro-regenerative properties according to its level at the site of lesion.
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Neurogénesis/efectos de los fármacos , Nódulos de Ranvier/efectos de los fármacos , Células de Schwann/efectos de los fármacos , Trombina/farmacología , Animales , Calcio/metabolismo , Femenino , Masculino , Neuritas/efectos de los fármacos , Células PC12 , Pirroles/farmacología , Quinazolinas/farmacología , Ratas , Ratas Wistar , Receptor PAR-1/metabolismo , Nervio Ciático/efectos de los fármacos , Tapsigargina/farmacologíaRESUMEN
The immunohistochemical profile of neurotrophins and their receptors in the human cranial dura mater was studied by examining certain dural zones in specimens harvested from different regions (frontal, temporal, parietal and occipital). Dural specimens were obtained during neurosurgical operations performed in ten patients for surgical treatment of intracranial lesions (meningiomas, traumas, gliomas, vascular malformations). The dural fragments were taken from the area of the craniotomy at least 8 cm from the lesion as well as from the area in which the meningioma had its dural attachment. Immunohistochemical characterization and distribution of neurotrophins, with their receptors, were analyzed. The concrete role played by these neurotrophic factors in general regulation, vascular permeability, algic responsivity and release of locally active substances in the human dura mater is still controversial. Our study revealed a general structural alteration of dural tissue due to the invasivity of meningiomatous lesions, together with an improved expression of brain derived neurotrophic factor (BDNF) in highly proliferating neoplastic cells and an evident production of nerve growth factor (NGF) in inflammatory cells, suggesting that BDNF has a role in supporting the proliferation rate of neoplastic cells, while NGF is involved in the activation of a chronic inflammatory response in neoplastic areas.
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Duramadre/química , Inmunohistoquímica , Neoplasias Meníngeas/química , Meningioma/química , Factores de Crecimiento Nervioso/análisis , Adulto , Anciano , Factor Neurotrófico Derivado del Encéfalo/análisis , Craneotomía , Duramadre/patología , Duramadre/cirugía , Humanos , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patología , Neoplasias Meníngeas/cirugía , Meningioma/genética , Meningioma/patología , Meningioma/cirugía , Persona de Mediana Edad , Factor de Crecimiento Nervioso/análisis , Factores de Crecimiento Nervioso/genética , ARN Mensajero/análisis , Receptores de Factor de Crecimiento Nervioso/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Protease-activated receptors (PARs) are cleaved and activated by thrombin and other extracellular proteases which are released during tissue trauma and inflammation. PAR-1 is the prototypic member of the PAR family and has been shown to be upregulated in several brain pathologies being expressed by neurons and glial cells. The present experiments show that the administration of the PAR-1 activating peptides (TRAP6 and TFLLR) inhibits the production of the pro-inflammatory cytokines TNF-alpha and IL-6 in microglial cells treated with lipopolysaccharide (LPS) while promoting the release of the anti-inflammatory cytokine IL-10. Conversely, the addition of the specific PAR-2 agonist SLIGRL had no effect on the amount of cytokines released following LPS treatment. Consistent with these data PAR-1, but not PAR-2, stimulation upregulates the expression of the suppressor of cytokine signaling-3 (SOCS-3). The present data support the hypothesis that in microglia PAR-1 may be involved in the regulation of inflammatory reactions modulating the balance between pro- and anti-inflammatory cytokines possibly through SOCS induction.
Asunto(s)
Citocinas/biosíntesis , Microglía/metabolismo , Receptor PAR-1/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Animales , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Lipopolisacáridos/farmacología , Ratones , Microglía/citología , Microglía/efectos de los fármacos , Oligopéptidos/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Receptor PAR-1/agonistas , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
The effect of ST1942, a 2-aminotetraline derivative with anti-inflammatory properties, was evaluated in ischemia/reperfusion injury in CD1 and C57BL/6 mice. ST1942 or saline were injected intraperitoneally 30 min and 6, 24, 36 h after ischemia. Forty-eight hours after ischemia, ST1942 (25 mg/kg) reduced the infarct volume by 50% in CD1 and 61% in C57BL/6 mice. All subsequent data were obtained from the latter strain. The ischemic lesion was significantly reduced by 30% when the first injection was administered 6 h after ischemia, revealing a broad effective window. Degenerating neurons in striatum, cortex and hippocampus of ischemic mice were markedly decreased by ST1942. Also examined was the effect of ST1942 on general and focal neurological deficits for 4 days after ischemia. Mice receiving the drug twice daily showed constantly reduced deficits. We then investigated the cortical mRNA expression of some inflammatory and apoptotic genes by real-time PCR. Forty-eight hours after ischemia ST1942 treatment significantly counteracted ischemia-induced activation of IL-1beta, TNFalpha, and Bax, and enhanced the expression of the antiapoptotic gene, Bcl-2, showing in vivo anti-inflammatory and antiapoptotic actions. The microglial activation/macrophage recruitment in the ischemic lesion was strongly prevented in mice receiving ST1942. In neuron-microglia cocultures, ST1942 significantly counteracted LPS-induced cytotoxicity. Binding data and experiments on microglial cell cultures indicate that the anti-inflammatory effect of ST1942 may be due to its action on 5-HT2B receptors, thus highlighting the possibility that this 5-HT receptor subtype may represent a novel target for neuroprotective drugs in ischemic injury.