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1.
Neurochem Res ; 48(6): 1864-1888, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36719560

RESUMO

Neuropathic pain is associated with abnormal sensations and/or pain induced by non-painful stimuli, i.e., allodynia causing burning or cold sensation, pinching of pins and needles like feeling, numbness, aching or itching. However, no suitable therapy exists to treat these pain syndromes. Our laboratory explored novel potential therapeutic strategies using a suitable composition of neurotrophic factors and active peptide fragments-Cerebrolysin (Ever Neuro Pharma, Austria) in alleviating neuropathic pain induced spinal cord pathology in a rat model. Neuropathic pain was produced by constrictions of L-5 spinal sensory nerves for 2-10 weeks period. In one group of rats cerebrolysin (2.5 or 5 ml/kg, i.v.) was administered once daily after 2 weeks until sacrifice (4, 8 and 10 weeks). Ag, Cu and Al NPs (50 mg/kg, i.p.) were delivered once daily for 1 week. Pain assessment using mechanical (Von Frey) or thermal (Hot-Plate) nociceptive showed hyperalgesia from 2 weeks until 10 weeks progressively that was exacerbated following Ag, Cu and Al NPs intoxication in nerve lesioned groups. Leakage of Evans blue and radioiodine across the blood-spinal cord barrier (BSCB) is seen from 4 to 10 weeks in the rostral and caudal cord segments associated with edema formation and cell injury. Immunohistochemistry of albumin and GFAP exhibited a close parallelism with BSCB leakage that was aggravated by NPs following nerve lesion. Light microscopy using Nissl stain exhibited profound neuronal damages in the cord. Transmission electron microcopy (TEM) show myelin vesiculation and synaptic damages in the cord that were exacerbated following NPs intoxication. Using ELISA spinal tissue exhibited increased albumin, glial fibrillary acidic protein (GFAP), myelin basic protein (MBP) and heat shock protein (HSP 72kD) upregulation together with cytokines TNF-α, IL-4, IL-6, IL-10 levels in nerve lesion that was exacerbated following NPs intoxication. Cerebrolysin treatment significantly reduced hyperalgesia and attenuated BSCB disruption, edema formation and cellular changes in nerve lesioned group. The levels of cytokines were also restored near normal levels with cerebrolysin treatment. Albumin, GFAP, MABP and HSP were also reduced in cerebrolysin treated group and thwarted neuronal damages, myelin vesiculation and cell injuries. These neuroprotective effects of cerebrolysin with higher doses were also effective in nerve lesioned rats with NPs intoxication. These observations suggest that cerebrolysin actively protects spinal cord pathology and hyperalgesia following nerve lesion and its exacerbation with metal NPs, not reported earlier.


Assuntos
Nanopartículas Metálicas , Neuralgia , Animais , Ratos , Albuminas/metabolismo , Albuminas/farmacologia , Citocinas/metabolismo , Edema/etiologia , Edema/metabolismo , Edema/patologia , Hiperalgesia/metabolismo , Radioisótopos do Iodo , Nanopartículas , Neuralgia/induzido quimicamente , Neuralgia/tratamento farmacológico , Neuralgia/complicações , Medula Espinal/metabolismo , Nanopartículas Metálicas/química
2.
Lab Invest ; 99(7): 958-970, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30760863

RESUMO

The identification of amyloid-ß precursor protein (APP) pathogenic mutations in familial early onset Alzheimer's disease (AD), along with knowledge that amyloid-ß (Aß) was the principle protein component of senile plaques, led to the establishment of the amyloid cascade hypothesis. Down syndrome substantiated the hypothesis, given an extra copy of the APP gene and invariable AD pathology hallmarks that occur by middle age. An abundance of support for the amyloid cascade hypothesis followed. Prion-like protein misfolding and non-Mendelian transmission of neurotoxicity are among recent areas of investigation. Aß-targeted clinical trials have been disappointing, with negative results attributed to inadequacies in patient selection, challenges in pharmacology, and incomplete knowledge of the most appropriate target. There is evidence, however, that proof of concept has been achieved, i.e., clearance of Aß during life, but with no significant changes in cognitive trajectory in AD. Whether the time, effort, and expense of Aß-targeted therapy will prove valuable will be determined over time, as Aß-centered clinical trials continue to dominate therapeutic strategies. It seems reasonable to hypothesize that the amyloid cascade is intimately involved in AD, in parallel with disease pathogenesis, but that removal of toxic Aß is insufficient for an effective disease modification.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/etiologia , Doença de Alzheimer/terapia , Humanos , Terapia de Alvo Molecular
3.
J Neurooncol ; 138(2): 241-250, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29453678

RESUMO

The TNF receptor superfamily member Fn14 is overexpressed by many solid tumor types, including glioblastoma (GBM), the most common and lethal form of adult brain cancer. GBM is notable for a highly infiltrative growth pattern and several groups have reported that high Fn14 expression levels can increase tumor cell invasiveness. We reported previously that the mesenchymal and proneural GBM transcriptomic subtypes expressed the highest and lowest levels of Fn14 mRNA, respectively. Given the recent histopathological re-classification of human gliomas by the World Health Organization based on isocitrate dehydrogenase 1 (IDH1) gene mutation status, we extended this work by comparing Fn14 gene expression in IDH1 wild-type (WT) and mutant (R132H) gliomas and in cell lines engineered to overexpress the IDH1 R132H enzyme. We found that both low-grade and high-grade (i.e., GBM) IDH1 R132H gliomas exhibit low Fn14 mRNA and protein levels compared to IDH1 WT gliomas. Forced overexpression of the IDH1 R132H protein in glioma cells reduced Fn14 expression, while treatment of IDH1 R132H-overexpressing cells with the IDH1 R132H inhibitor AGI-5198 or the DNA demethylating agent 5-aza-2'-deoxycytidine increased Fn14 expression. These results support a role for Fn14 in the more aggressive and invasive phenotype associated with IDH1 WT tumors and indicate that the low levels of Fn14 gene expression noted in IDH1 R132H mutant gliomas may be due to epigenetic regulation via changes in DNA methylation.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Glioma/genética , Glioma/metabolismo , Mutação , Receptor de TWEAK/metabolismo , Biomarcadores Tumorais/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Citocina TWEAK/metabolismo , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Gradação de Tumores , RNA Mensageiro/metabolismo , Estudos Retrospectivos
4.
Am J Forensic Med Pathol ; 38(2): 126-130, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28319470

RESUMO

The pathophysiology of acute-on-chronic subdural hematoma (ACSDH) is complex and incompletely understood. Evidence to date indicates that the overall process is initiated by rotational force with movement of the brain inside the skull, which exerts tensile strain and rupture of bridging veins, leading in turn to acute hemorrhage in the subdural potential space. This is followed by the proliferation of mesenchymal elements with angiogenesis and inflammation, which in turn becomes a substrate for repeated hemorrhage and expansion of the lesion. Given the prevalence of traumatic subdural processes in the forensic setting and the importance of proper assessment of timing, etiology, risk factors, and clinicopathological correlation, we studied 47 patients presenting to the University of Maryland Shock Trauma Center, all of whom underwent craniotomy with resection of the outer membrane due to symptomatic ACSDH. The surgically resected tissue was examined for histopathologic features in all cases. Our findings highlight that ACSDH is a condition precipitated by trauma that affects middle-aged and older adults, is relatively indolent, is unilateral or asymmetric, and has a low in-hospital mortality rate. Pathological analysis demonstrates a substantial outer membrane in all cases with varying degrees of inflammation and organization that cannot be precisely dated as a function of clinical presentation. The extrapolation of adult ACSDH to mixed acute and chronic subdural hemorrhage in the pediatric setting is problematic due to substantial differences in clinical presentation, severity of underlying brain injury, gross and microscopic findings, and outcome.


Assuntos
Hematoma Subdural Agudo/patologia , Hematoma Subdural Crônico/patologia , Acidentes por Quedas/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Craniotomia , Eosinófilos/patologia , Feminino , Escala de Coma de Glasgow , Hematoma Subdural Agudo/cirurgia , Hematoma Subdural Crônico/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Retrospectivos , Ferimentos e Lesões/epidemiologia
5.
J Neural Transm (Vienna) ; 123(2): 107-11, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25608860

RESUMO

Multiple lines of evidence suggest that vascular alterations contribute to Alzheimer's disease (AD) pathogenesis. It is also well established that mitochondrial abnormalities occur early in course of AD. Here, we give an overview of the vascular and mitochondrial abnormalities occurring in AD, including mitochondrial alterations in vascular endothelial cells within the brain, which is emerging as a common feature that bridges cerebral vasculature and mitochondrial metabolism.


Assuntos
Doença de Alzheimer/fisiopatologia , Encéfalo/fisiopatologia , Circulação Cerebrovascular/fisiologia , Mitocôndrias/fisiologia , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Humanos , Mitocôndrias/patologia
6.
Lab Invest ; 95(6): 576-84, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25867769

RESUMO

Chronic traumatic encephalopathy (CTE) has been in the medical literature since the 1920s. It is characterized clinically by diverse neuropsychiatric symptoms, and pathologically by variable degrees of phosphorylated tau accumulation in the brain. The evolving paradigm for the pathogenesis of CTE suggests that concussion or subconcussion from athletic participation initiates a cascade of pathologic events, encompassing neuroinflammation and protein templating with trans-synaptic neurotoxicity. The end result is neurologic and neurobehavioral deterioration, often with self-harm. Although these concepts warrant further investigation, the available evidence permits no conclusions as regards the pathogenesis of the reported findings. Investigations into the role of premorbid or co-morbid neurodegenerative diseases has been limited to date, and in-depth genetic analyses have not been performed. The role of concussion or subconcussion if any, whether and how the condition progresses over time, the extent of phosphorylated tau in clinically normal athletes, the role of phosphorylated tau as a toxic species versus an inert disease response, and whether protein templating has any in vivo relevance remain to be elucidated.


Assuntos
Traumatismos em Atletas , Lesão Encefálica Crônica , Doenças Priônicas , Humanos
7.
J Neurochem ; 130(1): 115-25, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24601954

RESUMO

Development of Alzheimer's disease (AD) has been linked to the de-regulation of estrogen and gonadotropins such as luteinizing hormone (LH). In this study, we found increases in AD pathology in the hippocampi of aged female 3xTg AD mice after ovariectomy that were unable to be reduced by estrogen therapy or down-regulation of serum LH levels. Despite the lack of effect of these treatments on AD pathology, down-regulation of serum LH but not estrogen improved factors associated with neuronal plasticity such as spatial memory, inhibition of glycogen synthase kinase-3 beta, expression of beta-catenin, and brain-derived neurotrophic factor transcription. Contrasting previous studies in younger mice, estrogen replacement was not able to rescue behavioral deficits, reduced glycogen synthase kinase-3 beta inhibition and increased hippocampal phosphorylation of tau. Of critical importance, serum LH was negatively correlated with brain LH in regions associated with spatial memory, and increases in brain LH correlated with cognitive improvement. This paralleled changes in human female AD brains which showed a significant reduction in brain LH mRNA compared to healthy age- and PMI-matched controls. Taken together, these findings should promote further research into the LH-dependent mechanisms associated with AD cognitive deficits as well as the effects of estrogen within the aged brain. In the aged triple transgenic Alzheimer's disease (AD) mouse model (3xAD-Tg), estrogen replacement after ovariectomy does not improve cognitive function, increases phosphorylated Tau levels and decreases inhibition of GSK3 beta. Luprolide acetate rescues ovariectomy-dependent cognitive function, increases signaling events associated with synaptic plasticity including GSK3 beta inhibition, but does not alter AD pathology. In the human AD female brain, luteinizing hormone (LH) mRNA levels are reduced. In the 3XAD-tg model, brain LH protein levels are reduced by ovariectomy and normalized by leuprolide acetate treatment. These treatment-dependent normalization of LH positively correlates with markers of neuroplasticity and cognitive improvement.


Assuntos
Envelhecimento/sangue , Cognição/fisiologia , Regulação para Baixo/fisiologia , Terapia de Reposição de Estrogênios/métodos , Estrogênios/administração & dosagem , Hormônio Luteinizante/sangue , Ovariectomia , Animais , Biomarcadores/sangue , Células Cultivadas , Feminino , Gonadotropinas/sangue , Hipocampo/metabolismo , Camundongos , Camundongos Transgênicos , Ratos , Ratos Sprague-Dawley
8.
Stroke ; 44(12): 3522-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24114458

RESUMO

BACKGROUND AND PURPOSE: Subarachnoid hemorrhage (SAH) can leave patients with memory impairments that may not recover fully. Molecular mechanisms are poorly understood, and no treatment is available. The sulfonylurea receptor 1-transient receptor potential melastatin 4 (Sur1-Trpm4) channel plays an important role in acute central nervous system injury. We evaluated upregulation of Sur1-Trpm4 in humans with SAH and, in rat models of SAH, we examined Sur1-Trpm4 upregulation, its role in barrier dysfunction and neuroinflammation, and its consequences on spatial learning. METHODS: We used Förster resonance energy transfer to detect coassociated Sur1 and Trpm4 in human autopsy brains with SAH. We studied rat models of SAH involving filament puncture of the internal carotid artery or injection of blood into the subarachnoid space of the entorhinal cortex. In rats, we used Förster resonance energy transfer and coimmunoprecipitation to detect coassociated Sur1 and Trpm4, we measured immunoglobulin G extravasation and tumor necrosis α overexpression as measures of barrier dysfunction and neuroinflammation, and we assessed spatial learning and memory on days 7 to 19. RESULTS: Sur1-Trpm4 channels were upregulated in humans and rats with SAH. In rats, inhibiting Sur1 using antisense or the selective Sur1 inhibitor glibenclamide reduced SAH-induced immunoglobulin G extravasation and tumor necrosis α overexpression. In models with entorhinal SAH, rats treated with glibenclamide for 7 days after SAH exhibited better platform search strategies and better performance on incremental and rapid spatial learning than vehicle-treated controls. CONCLUSIONS: Sur1-Trpm4 channels are upregulated in humans and rats with SAH. Channel inhibition with glibenclamide may reduce neuroinflammation and the severity of cognitive deficits after SAH.


Assuntos
Transtornos Cognitivos/metabolismo , Encefalite/metabolismo , Hemorragia Subaracnóidea/metabolismo , Receptores de Sulfonilureias/antagonistas & inibidores , Canais de Cátion TRPM/antagonistas & inibidores , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Transtornos Cognitivos/genética , Transtornos Cognitivos/fisiopatologia , Encefalite/genética , Encefalite/fisiopatologia , Glibureto/farmacologia , Humanos , Aprendizagem em Labirinto/efeitos dos fármacos , Ratos , Hemorragia Subaracnóidea/genética , Hemorragia Subaracnóidea/fisiopatologia , Regulação para Cima/efeitos dos fármacos
9.
J Neuroinflammation ; 10: 127, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24139179

RESUMO

BACKGROUND: The human ß-defensins (hBDs) are a highly conserved family of cationic antimicrobial and immunomodulatory peptides expressed primarily by epithelial cells in response to invasion by bacteria, fungi and some viruses. To date, the most studied members of this family of peptides are hBD-1, -2, and -3. Expression of hBD-1 and -2 has been demonstrated previously in cultured microglia and astrocytes of both mouse and human brain. Unlike inducible hBD-2 and -3, hBD-1 is constitutively expressed and is not generally upregulated by proinflammatory factors. In this study, we investigated whether hBDs, as active components of the innate immune response, are affected by pathological events in the Alzheimer's disease (AD) brain. We assessed the expression of hBD-1, -2, and -3 in tissue obtained at autopsy from AD and age-matched control brains. METHODS: Fixed and frozen choroid plexus and the CA1 region of the hippocampus were obtained at autopsy from individuals diagnosed with AD, or from age-matched control brains without diagnosed neurodegenerative disease. Histopathologically diagnosed AD brain tissue was obtained for our study. Immunocytochemical analysis was performed using affinity purified polyclonal antibodies directed against hBD-1, -2, or -3. TaqMan gene expression assays were used to quantify the mRNA of hBD-1, -2, and -3 in the choroid plexus and hippocampus. Immunocytochemical detection of iron deposits was achieved using a modified Perl's stain for redox-active iron. In vitro experiments were performed on human primary oral epithelial cells to model the human choroid plexus epithelial response to ferric chloride. Cells were then exposed to ferric chloride added to selected wells at 0, 1, or 10 mM concentrations for 24 h at 37°C. Total mRNA was isolated to quantify hBD-1 mRNA expression by RTqPCR. RESULTS: hBD-1 peptide is apparent in astrocytes of the AD hippocampus and hippocampal neurons, notably within granulovacuolar degeneration structures (GVD). A higher level of hBD-1 was also seen in the choroid plexus of AD brain in comparison to age-matched control tissue. Increased expression of hBD-1 mRNA was observed only in the choroid plexus of the AD brain when compared to expression level in age-matched control brain. Redox-active iron was also elevated in the AD choroid plexus and in vitro addition of Fe⁺³Cl3 to cultured epithelial cells induced hBD-1 mRNA expression. CONCLUSIONS: Our findings suggest interplay between hBD-1 and neuroimmunological responses in AD, marked by microglial and astrocytic activation, and increased expression of the peptide within the choroid plexus and accumulation within GVD. As a constitutively expressed component of the innate immune system, we propose that hBD-1 may be of considerable importance early in the disease process. We also demonstrate that increased iron deposition in AD may contribute to the elevated expression of hBD-1 within the choroid plexus. These findings represent a potentially important etiological aspect of Alzheimer's disease neuropathology not previously reported.


Assuntos
Doença de Alzheimer/metabolismo , Biomarcadores/análise , Plexo Corióideo/metabolismo , Hipocampo/metabolismo , beta-Defensinas/biossíntese , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Ferro/metabolismo , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Oxirredução , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
10.
Brain Commun ; 5(4): fcad203, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492487

RESUMO

This scientific commentary refers to 'Key questions for the evaluation of anti-amyloid immunotherapies for Alzheimer's disease', by Liu et al. (https://doi.org/10.1093/braincomms/fcad175).

11.
J Neurochem ; 121(4): 672-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22393900

RESUMO

Fragile X syndrome (FXS) is a developmental disorder caused by the loss of Fragile X Mental Retardation 1 (FMR1) gene function because of a CGG repeat expansion (> 200 repeats) in the gene. The molecular mechanism(s) linking loss of FMR1 function to the molecular pathology and cognitive/behavioral disability remain unclear. Given the critical role of extracellular signal-regulated kinase (ERK) in synaptic plasticity and neurodevelopment, a number of recent studies have investigated ERK phosphorylation under basal conditions or upon mGluR-induction using neuronal and peripheral tissues from Fmr1 knockout mice and peripheral tissues from FXS patients. However, these reports have presented conflicting results. The current study is the first to focus on the levels of ERK phosphorylation in brain tissue from human FXS patients. In both human brain tissue and brain tissue from Fmr1 knockout mice there was significantly increased phosphorylation of MEK1/2 and ERK. Indeed, treating Fmr1 knockout mice with the MEK1/2 inhibitor SL327 abrogated audiogenic seizure activity, a feature of the Fmr1 knockout mice that replicates the symptom in patients with FXS. These findings suggest that activation of the ERK pathway results in some cardinal cognitive and clinical features in FXS patients and likely have profound translational implications.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Síndrome do Cromossomo X Frágil/psicologia , Transdução de Sinais/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminoacetonitrila/análogos & derivados , Aminoacetonitrila/farmacologia , Animais , Western Blotting , Criança , Ativação Enzimática/fisiologia , Feminino , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/genética , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Fosforilação , Inibidores de Proteases/farmacologia , Convulsões/genética , Adulto Jovem
12.
J Pathol ; 224(2): 147-52, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21557219

RESUMO

With each failure of anti-amyloid-ß therapy in clinical trials, new trials are initiated with no hint of slowing down. This may be due, in part, to the fact that the amyloid cascade hypothesis has been so modified over time that it is now impossible to confirm or deny. The hypothesis now states, in effect, that invisible molecules target invisible structures. Still relevant, however, are multiple factors that surely cast some doubt but have either been rationalized or overlooked. Among these are the poor correlation between amyloid-ß deposits and disease, the substantial differences between familial and sporadic disease, pathological assessment that indicates the secondary nature of lesions/proteins/cascades, the fact that soluble species are poorly reproducible laboratory phenomena, and the irrelevance of synaptic assessment to pathological interpretation. Although not yet dogma, the premature addition of mild cognitive impairment as the implied in vivo homologue to the soluble toxin-synapse interaction is also problematic. In either case, the amyloid cascade hypothesis continues to dominate the Alzheimer's disease literature and grant applications. The more the neuroscience community perseverates along these lines in the face of accumulating outcome data to the contrary, the more one is left to wonder whether the hypothesis is too big to fail.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Idoso , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Artefatos , Transtornos Cognitivos/metabolismo , Progressão da Doença , Humanos , Terapia de Alvo Molecular/métodos , Mutação
15.
ScientificWorldJournal ; 2012: 905785, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22606066

RESUMO

It is widely accepted that the brain responds to mechanical trauma and development of most neurodegenerative diseases with an inflammatory sequelae that was once thought exclusive to systemic immunity. Mostly cationic peptides, such as the ß-defensins, originally assigned an antimicrobial function are now recognized as mediators of both innate and adaptive immunity. Herein supporting evidence is presented for the hypothesis that neuropathological changes associated with chronic disease conditions of the CNS involve abnormal expression and regulatory function of specific antimicrobial peptides. It is also proposed that these alterations exacerbate proinflammatory conditions within the brain that ultimately potentiate the neurodegenerative process.


Assuntos
Peptídeos Catiônicos Antimicrobianos/imunologia , Doenças Neurodegenerativas/imunologia , beta-Defensinas/imunologia , Imunidade Adaptativa , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Apoptose , Astrócitos/imunologia , Astrócitos/metabolismo , Encéfalo/imunologia , Encéfalo/metabolismo , Encéfalo/patologia , Proliferação de Células , Doenças do Sistema Nervoso Central/imunologia , Doenças do Sistema Nervoso Central/metabolismo , Doenças do Sistema Nervoso Central/patologia , Quimiotaxia , Plexo Corióideo/imunologia , Plexo Corióideo/metabolismo , Citocinas/imunologia , Células Dendríticas/imunologia , Humanos , Imunidade Inata , Mediadores da Inflamação/imunologia , Microglia/imunologia , Microglia/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Cicatrização , beta-Defensinas/metabolismo
16.
Lab Invest ; 91(12): 1777-86, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21968813

RESUMO

The phosphorylated ribosomal protein S6 (pS6) is associated with the 40S ribosomal subunit in eukaryotes and is thought to have a role in RNA storage, degradation, and re-entry into translation. In this study, we found pS6 localized to granulovacuolar degeneration (GVD) within the pyramidal neurons. Immunohistochemical analysis found that nearly 20-fold more neurons contain pS6-positive granules in Alzheimer's disease (AD) hippocampus compared with age-matched controls. Further, pS6-positive granules were more common in neurons not containing neurofibrillary tangles (NFTs), were never associated with extracellular NFTs or in apoptotic neurons, and contained less RNA than neighboring pyramidal neurons not containing pS6-positive granules. In model systems, pS6 is a specific marker for stress granules, and another stress granule protein, p54/Rck, was also found to be a component of GVD in the current study. Stress granules are transient, intracellular, dense aggregations of proteins and RNAs that accumulate as a stress response, protecting cells from apoptosis and inappropriate transcriptional activity, often described as a form of 'molecular triage.' The RNA oxidation modification 8-hydroxyguanosine (8OHG) is strikingly increased in AD, yet this study reports that those neurons with pS6 granules display reduced RNA oxidation demonstrated by lower levels of 8OHG. Since chronic oxidative stress is central to AD pathogenesis, and RNA is a specific oxidative stress target and is intimately associated with stress granule biogenesis in model systems, we suggest that GVD in human brain parallel stress granules, and may in fact be more representative of early disease pathogenesis than traditionally believed. This proposed origin for GVD as a neuroprotective response, may represent a morphologic checkpoint between cell death and reversible cellular stress that proceeds in the absence of other inclusions.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/patologia , Células Piramidais/patologia , Proteína S6 Ribossômica/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Masculino , Emaranhados Neurofibrilares , Oxirredução , Estresse Oxidativo , Células Piramidais/metabolismo , RNA Ribossômico/metabolismo , Adulto Jovem
17.
J Neural Transm (Vienna) ; 118(1): 23-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20972807

RESUMO

CD3ζ is a subunit of the CD3 molecule that, until recently, appeared restricted to T cells and natural killer cells. However, experimental studies have demonstrated a role of CD3ζ in dendritic outgrowth in the visual system as well as in synaptic plasticity. Given the increasing evidence for uncharacteristic recapitulation of neurodevelopmental processes in neurodegenerative diseases, in this study, we evaluated brains from subjects with Parkinson's disease and Lewy body dementia for evidence of aberrant CD3 expression. Our data shows marked CD3ζ in association with the α-synuclein containing pathological lesions, i.e., Lewy bodies and Lewy neurites, in the brains of subjects with Parkinson's disease and Lewy body dementia. This finding raises the novel concept of CD3 dysregulation in these disorders as a pathogenic factor and also furthers the increasing evidence that the recall of aberrant neurodevelopmental processes underlies the pathogenesis of neurodegenerative diseases.


Assuntos
Complexo CD3/metabolismo , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Feminino , Humanos , Imuno-Histoquímica , Corpos de Lewy/patologia , Corpos de Lewy/ultraestrutura , Masculino , Pessoa de Meia-Idade , alfa-Sinucleína/metabolismo
18.
Cureus ; 13(2): e13537, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33786244

RESUMO

Chordoid gliomas arise near the third ventricle and commonly present around 40 years of age. These rare tumors are non-invasive and often present with headaches and visual disturbances. Contrast enhancement on MRI is typical for these tumors and immunohistochemical (IHC) staining is positive for glial fibrillary acidic protein (GFAP). Surgical resection is the treatment of choice. We present this case of chordoid glioma because of its unique characteristics. The tumor lacked contrast enhancement on MRI and demonstrated juxtanuclear dot-like immunoreactivity for synaptophysin which is a feature not previously reported in the literature. It is important for pathologists and radiologists to be on the lookout for atypical presentations of these rare tumors.

19.
Prog Brain Res ; 266: 211-267, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34689860

RESUMO

Concussive head injury (CHI) often associated with military personnel, soccer players and related sports personnel leads to serious clinical situation causing lifetime disabilities. About 3-4k head injury per 100k populations are recorded in the United States since 2000-2014. The annual incidence of concussion has now reached to 1.2% of population in recent years. Thus, CHI inflicts a huge financial burden on the society for rehabilitation. Thus, new efforts are needed to explore novel therapeutic strategies to treat CHI cases to enhance quality of life of the victims. CHI is well known to alter endogenous balance of excitatory and inhibitory amino acid neurotransmitters in the central nervous system (CNS) leading to brain pathology. Thus, a possibility exists that restoring the balance of amino acids in the CNS following CHI using therapeutic measures may benefit the victims in improving their quality of life. In this investigation, we used a multimodal drug Cerebrolysin (Ever NeuroPharma, Austria) that is a well-balanced composition of several neurotrophic factors and active peptide fragments in exploring its effects on CHI induced alterations in key excitatory (Glutamate, Aspartate) and inhibitory (GABA, Glycine) amino acids in the CNS in relation brain pathology in dose and time-dependent manner. CHI was produced in anesthetized rats by dropping a weight of 114.6g over the right exposed parietal skull from a distance of 20cm height (0.224N impact) and blood-brain barrier (BBB), brain edema, neuronal injuries and behavioral dysfunctions were measured 8, 24, 48 and 72h after injury. Cerebrolysin (CBL) was administered (2.5, 5 or 10mL/kg, i.v.) after 4-72h following injury. Our observations show that repeated CBL induced a dose-dependent neuroprotection in CHI (5-10mL/kg) and also improved behavioral functions. Interestingly when CBL is delivered through TiO2 nanowires superior neuroprotective effects were observed in CHI even at a lower doses (2.5-5mL/kg). These observations are the first to demonstrate that CBL is effectively capable to attenuate CHI induced brain pathology and behavioral disturbances in a dose dependent manner, not reported earlier.


Assuntos
Traumatismos Craniocerebrais , Fármacos Neuroprotetores , Preparações Farmacêuticas , Aminoácidos , Animais , Encéfalo , Fármacos Neuroprotetores/farmacologia , Qualidade de Vida , Ratos , Titânio
20.
Prog Brain Res ; 266: 357-376, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34689864

RESUMO

Spinal cord injury (SCI) is one of the leading causes of disability in Military personnel for which no suitable therapeutic strategies are available till today. Thus, exploration of novel therapeutic measures is highly needed to enhance the quality of life of SCI victims. Previously, topical application of BDNF and GDNF in combination over the injured spinal cord after 90min induced marked neuroprotection. In present investigation, we added CNTF in combination with BDNF and/or GDNF treatment to examine weather the triple combination applied over the traumatic cord after 90 or 120min could thwart cord pathology. Since neurotrophins attenuate nitric oxide (NO) production in SCI, the role of carbon monoxide (CO) production that is similar to NO in inducing cell injury was explored using immunohistochemistry of the constitutive isoform of enzyme hemeoxygenase-2 (HO-2). SCI inflicted over the right dorsal horn of the T10-11 segments by making an incision of 2mm deep and 5mm long upregulated the HO-2 immunostaining in the T9 and T12 segments after 5h injury. These perifocal segments are associated with breakdown of the blood-spinal cord barrier (BSCB), edema development and cell injuries. Topical application of CNTF with BDNF and GDNF in combination (10ng each) after 90 and 120min over the injured spinal cord significantly attenuated the BSCB breakdown, edema formation, cell injury and overexpression of HO-2. These observations are the first to show that CNTF with BDNF and GDNF induced superior neuroprotection in SCI probably by downregulation of CO production, not reported earlier.


Assuntos
Fármacos Neuroprotetores , Traumatismos da Medula Espinal , Fator Neurotrófico Derivado do Encéfalo , Fator Neurotrófico Ciliar , Edema , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Humanos , Fármacos Neuroprotetores/farmacologia , Permeabilidade , Qualidade de Vida , Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Regulação para Cima
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