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1.
J Neurochem ; 155(3): 313-326, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31853971

RESUMEN

One of the neuropathological hallmarks of the tauopathies is the formation of neuronal cytoplasmic inclusions and fibrils of microtubule-associated tau protein (tau). The phosphorylation of Thr175 of tau (pThr175 tau) appears to be sufficient for fibril formation in vitro and in vivo, but the mechanism by which this initiates fibril formation is unknown. Using transient transfections of tau mutants into HEK293T cells, we determined that the phosphorylation of Thr175 leads to exposure of the tau N-terminal phosphatase-activating domain (PAD). The exposed PAD is known to interact with protein phosphatase-1 (PP1) resulting in glycogen synthase kinase 3ß (GSK3ß) activation. In vivo, a single traumatic controlled cortical injury in rats also resulted in the phosphorylation of Thr175 and increased exposure of tau PAD followed by pathological tau fibril formation. Taken together, these data suggest that neurotoxicity may be precipitated by phosphorylation at Thr175 and subsequent tau PAD exposure, GSK3ß activation and tau fibril formation. Cover Image for this issue: doi: 10.1111/jnc.14767.


Asunto(s)
Amiloide/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Treonina/metabolismo , Proteínas tau/metabolismo , Animales , Femenino , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Células HEK293 , Humanos , Fosforilación/fisiología , Ratas , Ratas Sprague-Dawley
2.
Brain ; 141(5): 1320-1333, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29562314

RESUMEN

See Fratta and Isaacs (doi:10.1093/brain/awy091) for a scientific commentary on this article.The RNA binding proteins TDP-43 (encoded by TARDBP) and hnRNP A1 (HNRNPA1) are each mutated in certain amyotrophic lateral sclerosis cases and are often mislocalized in cytoplasmic aggregates within motor neurons of affected patients. Cytoplasmic inclusions of TDP-43, which are accompanied by a depletion of nuclear TDP-43, are observed in most amyotrophic lateral sclerosis cases and nearly half of frontotemporal dementia cases. Here, we report that TDP-43 binds HNRNPA1 pre-mRNA and modulates its splicing, and that depletion of nuclear TDP-43 results in increased inclusion of a cassette exon in the HNRNPA1 transcript, and consequently elevated protein levels of an isoform containing an elongated prion-like domain, referred to as hnRNP A1B. Combined in vivo and in vitro approaches demonstrated greater fibrillization propensity for hnRNP A1B, which drives protein aggregation and is toxic to cells. Moreover, amyotrophic lateral sclerosis patients with documented TDP-43 pathology showed neuronal hnRNP A1B cytoplasmic accumulation, indicating that TDP-43 mislocalization may contribute to neuronal vulnerability and loss via altered HNRNPA1 pre-mRNA splicing and function. Given that TDP-43 and hnRNP A1 each bind, and thus modulate, a third of the transcriptome, our data suggest a much broader disruption in RNA metabolism than previously considered.


Asunto(s)
Empalme Alternativo/genética , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Proteínas de Unión al ADN/metabolismo , Ribonucleoproteína Nuclear Heterogénea A1/genética , Agregación Patológica de Proteínas/metabolismo , Empalme Alternativo/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Muerte Celular/genética , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , Proteínas de Unión al ADN/genética , Dactinomicina/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Células HEK293 , Células HeLa , Ribonucleoproteína Nuclear Heterogénea A1/metabolismo , Humanos , Inmunoprecipitación , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/metabolismo , Mutación/genética , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Oligopéptidos/genética , Oligopéptidos/metabolismo , Sitios de Empalme de ARN/efectos de los fármacos , Sitios de Empalme de ARN/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Médula Espinal/patología , Transfección
3.
Explor Res Clin Soc Pharm ; 11: 100312, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37576805

RESUMEN

Background: Community pharmacists are expected to uphold ethical duties to patients and society while maintaining independent businesses or fulfilling expectations of corporate owners. Canadian pharmacy colleges provide only indirect guidance on the retail setting of the profession. Little is known about whether pharmacists identify ethical issues in retail pharmacy or around the sales of non-drug products. Objective: This study sought to examine pharmacists' perceptions of their roles in health promotion, the factors that influence the selection of front-of-store products, and ethical issues relating to their dual roles as health care providers and retailers. Methods: In 2020, 25 Canadian pharmacists participated in semi-structured phone interviews. Interviews were audio-recorded, anonymized, transcribed verbatim, and thematically analyzed using qualitative methods. Results: Almost all participants described their role primarily as a health care provider, though some described themselves as 50-50 health care providers and retailers. Most staff pharmacists reported little control over front-of-store product selection. Where participants reported some control, external factors such as business viability and profitability impacted their choices, though some reported selecting products based on the needs of their patient community or their personal beliefs. The dominant tensions described stemmed from participants' dual roles as health care providers and retailers, though specific issues and situations were varied, ranging corporate targets, to service provision, to the sales of unproven or unhealthy products. Participants suggested solutions to the issues they described, ranging from a complete overhaul of the licensing structure of community pharmacies, down to one-on-one conversations with patients. Conclusion: Our findings suggest that the retail setting of community pharmacy produces unique ethical tensions: the imposition of retail sales standards and targets are commonplace, and business viability is a primary driving force in front-of-store product selection. Clear guidance from Canadian pharmacy colleges and legislators to address these tensions and issues may be necessary.

4.
Front Cell Neurosci ; 16: 851563, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35431812

RESUMEN

Introduction: Recent studies have implicated changes in the blood-central nervous system barriers (BCNSB) in amyotrophic lateral sclerosis (ALS). The objective of this scoping review is to synthesize the current evidence for BCNSB structure and functional abnormalities in ALS studies and propose how BCNSB pathology may impact therapeutic development. Methods: A literature search was conducted using Ovid Medline, EMBASE, and Web of Science, from inception to November 2021 and limited to entries in English language. Simplified search strategy included the terms ALS/motor neuron disease and [BCNSB or blood-brain barrier (BBB) or blood-spinal cord barrier (BSCB)]. Henceforth, BCNSB is used as a term that is inclusive of the BBB and BSCB. Four independent reviewers conducted a title and abstract screening, hand-searched the reference lists of review papers, and performed a full text review of eligible studies. Included studies were original peer-reviewed full text publications, evaluating the structure and function of the BCNSB in preclinical models of ALS, clinical ALS, or postmortem human ALS tissue. There was no restriction on study design. The four reviewers independently extracted the data. Results: The search retrieved 2,221 non-duplicated articles and 48 original studies were included in the synthesis. There was evidence that the integrity of the BCNSB is disrupted throughout the course of the disease in rodent models, beginning prior to symptom onset and detectable neurodegeneration. Increased permeability, pharmacoresistance with upregulated efflux transporters, and morphological changes in the supporting cells of the BCNSB, including pericytes, astrocytes, and endothelial cells were observed in animal models. BCNSB abnormalities were also demonstrated in postmortem studies of ALS patients. Therapeutic interventions targeting BCNSB dysfunction were associated with improved motor neuron survival in animal models of ALS. Conclusion: BCNSB structural and functional abnormalities are likely implicated in ALS pathophysiology and may occur upstream to neurodegeneration. Promising therapeutic strategies targeting BCNSB dysfunction have been tested in animals and can be translated into ALS clinical trials.

5.
J Neuroimaging ; 31(5): 879-892, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34473386

RESUMEN

BACKGROUND AND PURPOSE: Identification of changesin brain microstructure following mild traumatic brain injury (mTBI) could be instrumental in understanding the underlying pathophysiology. The purpose of this study was to apply neurite orientation dispersion and density imaging (NODDI) to a rodent model of mTBI to determine whether microstructural changes could be detected immediately following injury. METHODS: Fifteen adult male Wistar rats were scanned on a Bruker 9.4 Tesla small animal MRI using a multi-shell acquisition (30 b = 1000 s/mm2 and 60 b = 2000 s/mm2 ). Nine animals experienced a single closed head controlled cortical impact followed by NODDI from 1 to 4 h post injury. Region of interest analysis focused on the corpus callosum and hippocampus. A mixed analysis of variance (ANOVA) was used to determine statistically significant interactions in neurite density index (NDI), orientation dispersion index (ODI), fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity. Follow up repeated-measures ANOVAs were used to determine individual changes over time. RESULTS: NDI showed a significant increase in the hippocampus and corpus callosum following injury, while ODI showed increases in the corpus callosum. No significant changes were observed in the sham control animals. No changes were found in FA, MD, AD, or RD. Histological analysis revealed increased glial fibrillary acidic protein staining relative to controls in both the hippocampus and corpus callosum, with evidence of activated astrocytes in these regions. CONCLUSIONS: Changes in NODDI metrics were detected as early as 1 h following mTBI. No changes were detected with conventional diffusion tensor imaging (DTI) metrics, suggesting that NODDI provides greater sensitivity to microstructural changes than conventional DTI.


Asunto(s)
Conmoción Encefálica , Imagen de Difusión Tensora , Animales , Encéfalo , Conmoción Encefálica/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Masculino , Neuritas , Ratas , Ratas Wistar , Roedores
6.
Appl Immunohistochem Mol Morphol ; 28(7): 562-565, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31652146

RESUMEN

Many disorders of the central nervous system are characterized by both axonal pathology and demyelination. In assessing this concurrent pathology, techniques for staining axons or myelin are frequently used separately. Here we report the development of a combined immunohistochemical and tinctorial staining technique in which we have modified the Luxol fast blue myelin stain to be used in conjunction with a diaminobenzidine-based immunohistochemical stain for high molecular weight neurofilament (SMI-31). This modification of staining will have utility in experimental neuropathology laboratories investigating demyelination and axonal damage in human tissue and animal models.


Asunto(s)
Axones/metabolismo , Inmunohistoquímica/métodos , Filamentos Intermedios/metabolismo , Vaina de Mielina/metabolismo , Médula Espinal/metabolismo , Coloración y Etiquetado/métodos , Esclerosis Amiotrófica Lateral , Animales , Axones/patología , Humanos , Indoles , Filamentos Intermedios/patología , Vaina de Mielina/patología , Ratas , Ratas Sprague-Dawley , Médula Espinal/patología
7.
Sci Rep ; 9(1): 19928, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31882736

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a devastating progressive neurodegenerative disease with no known etiology. The formation of pathological protein inclusions, including RNA-binding proteins such as TDP-43 and rho guanine nucleotide exchange factor (RGNEF) are a hallmark of ALS. Despite intensive research, the mechanisms behind protein aggregate formation in ALS remains unclear. We have investigated the role of metabolic stress in protein aggregate formation analyzing how it is relevant to the co-aggregation observed between RGNEF and TDP-43 in motor neurons of ALS patients. Metabolic stress was able to induce formation of micronuclei, small nuclear fragments, in cultured cells. Notably, we observed the formation TDP-43 protein inclusions within micronuclei that co-aggregate with RGNEF and can be released to the cytoplasm. We observed that the leucine-rich domain of RGNEF is critical for its interaction with TDP-43 and localization in micronuclei. Finally, we described that micronuclei-like structures can be found in brain and spinal cord of ALS patients. This work is the first description of protein inclusion formation within micronuclei which also is linked with a neurodegenerative disease. The formation of TDP-43 inclusions within micronuclei induced by metabolic stress is a novel mechanism of protein aggregate formation which may have broad relevance for ALS and other neurodegenerative diseases.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Proteínas de Unión al ADN/metabolismo , Esclerosis Amiotrófica Lateral/genética , Animales , Western Blotting , Proteínas de Unión al ADN/genética , Femenino , Técnica del Anticuerpo Fluorescente , Células HEK293 , Humanos , Inmunoprecipitación , Cuerpos de Inclusión/metabolismo , Neuronas Motoras/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Médula Espinal/metabolismo
8.
Acta Neuropathol Commun ; 7(1): 170, 2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31703746

RESUMEN

Although it has been suggested that the co-expression of multiple pathological proteins associated with neurodegeneration may act synergistically to induce more widespread neuropathology, experimental evidence of this is sparse. We have previously shown that the expression of Thr175Asp-tau (tauT175D) using somatic gene transfer with a stereotaxically-injected recombinant adeno-associated virus (rAAV9) vector induces tau pathology in rat hippocampus. In this study, we have examined whether the co-expression of human tauT175D with mutant human TDP-43 (TDP-43M337V) will act synergistically. Transgenic female Sprague-Dawley rats that inducibly express mutant human TDP-43M337V using the choline acetyltransferase (ChAT) tetracycline response element (TRE) driver with activity modulating tetracycline-controlled transactivator (tTA) were utilized in these studies. Adult rats were injected with GFP-tagged tau protein constructs in a rAAV9 vector through bilateral stereotaxic injection into the hippocampus. Injected tau constructs were: wild-type GFP-tagged 2N4R human tau (tauWT; n = 8), GFP-tagged tauT175D 2N4R human tau (tauT175D, pseudophosphorylated, toxic variant, n = 8), and GFP (control, n = 8). Six months post-injection, mutant TDP-43M337V expression was induced for 30 days. Behaviour testing identified motor deficits within 3 weeks after TDP-43 expression irrespective of tau expression, though social behaviour and sensorimotor gating remained unchanged. Increased tau pathology was observed in the hippocampus of both tauWT and tauT175D expressing rats and tauT175D pathology was increased in the presence of cholinergic neuronal expression of human TDP-43M337V. These data indicate that co-expression of pathological TDP-43 and tau protein exacerbate the pathology associated with either individual protein.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Hipocampo/metabolismo , Hipocampo/fisiología , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Proteínas tau/metabolismo , Animales , Conducta Animal , Proteínas de Unión al ADN/toxicidad , Modelos Animales de Enfermedad , Femenino , Técnicas de Transferencia de Gen , Humanos , Actividad Motora , Ratas Sprague-Dawley , Ratas Transgénicas , Médula Espinal/metabolismo , Médula Espinal/patología , Proteínas tau/toxicidad
9.
Front Neurosci ; 12: 259, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29731706

RESUMEN

Approximately 50-60% of all patients with amyotrophic lateral sclerosis (ALS) will develop a deficit of frontotemporal function, ranging from frontotemporal dementia (FTD) to one or more deficits of neuropsychological, speech or language function which are collectively known as the frontotemporal spectrum disorders of ALS (ALS-FTSD). While the neuropathology underlying these disorders is most consistent with a widespread alteration in the metabolism of transactive response DNA-binding protein 43 (TDP-43), in both ALS with cognitive impairment (ALSci) and ALS with FTD (ALS-FTD; also known as MND-FTD) there is evidence for alterations in the metabolism of the microtubule associated protein tau. This alteration in tau metabolism is characterized by pathological phosphorylation at residue Thr175 (pThr175 tau) which in vitro is associated with activation of GSK3ß (pTyr216GSK3ß), phosphorylation of Thr231tau, and the formation of cytoplasmic inclusions with increased rates of cell death. This putative pathway of pThr175 induction of pThr231 and the formation of pathogenic tau inclusions has been recently shown to span a broad range of tauopathies, including chronic traumatic encephalopathy (CTE) and CTE in association with ALS (CTE-ALS). This pathway can be experimentally triggered through a moderate traumatic brain injury, suggesting that it is a primary neuropathological event and not secondary to a more widespread neuronal dysfunction. In this review, we discuss the neuropathological underpinnings of the postulate that ALS is associated with a tauopathy which manifests as a FTSD, and examine possible mechanisms by which phosphorylation at Thr175tau is induced. We hypothesize that this might lead to an unfolding of the hairpin structure of tau, activation of GSK3ß and pathological tau fibril formation through the induction of cis-Thr231 tau conformers. A potential role of TDP-43 acting synergistically with pathological tau metabolism is proposed.

10.
Neurology ; 90(5): e380-e387, 2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29298849

RESUMEN

OBJECTIVE: To investigate whether chronic traumatic encephalopathy (CTE) and CTE with amyotrophic lateral sclerosis (CTE-ALS) exhibit features previously observed in other tauopathies of pathologic phosphorylation of microtubule-associated protein tau at Thr175 (pThr175 tau) and Thr231 (pThr231 tau), and glycogen synthase kinase-3ß (GSK3ß) activation, and whether these pathologic features are a consequence of traumatic brain injury (TBI). METHODS: Tau isoform expression was assayed by western blot in 6 stage III CTE cases. We also used immunohistochemistry to analyze 5 cases each of CTE, CTE-ALS, and 5 controls for expression of activated GSK3ß, pThr175 tau, pThr231 tau, and oligomerized tau within spinal cord tissue and hippocampus. Using a rat model of moderate TBI, we assessed tau pathology and phospho-GSK3ß expression at 3 months postinjury. RESULTS: CTE and CTE-ALS are characterized by the presence of all 6 tau isoforms in both soluble and insoluble tau isolates. Activated GSK3ß, pThr175 tau, pThr231 tau, and oligomerized tau protein expression was observed in hippocampal neurons and spinal motor neurons. We observed tau neuronal pathology (fibrillar inclusions and axonal damage) and increased levels of pThr175 tau and activated GSK3ß in moderate TBI rats. CONCLUSIONS: Pathologic phosphorylation of tau at Thr175 and Thr231 and activation of GSK3ß are features of the tauopathy of CTE and CTE-ALS. These features can be replicated in an animal model of moderate TBI.


Asunto(s)
Esclerosis Amiotrófica Lateral/complicaciones , Esclerosis Amiotrófica Lateral/metabolismo , Encefalopatía Traumática Crónica/complicaciones , Encefalopatía Traumática Crónica/metabolismo , Treonina/metabolismo , Proteínas tau/metabolismo , Esclerosis Amiotrófica Lateral/patología , Animales , Encefalopatía Traumática Crónica/patología , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica/fisiología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hipocampo/metabolismo , Humanos , Masculino , Fosforilación , Ratas , Ratas Sprague-Dawley , Médula Espinal/patología
11.
J Neuropathol Exp Neurol ; 77(8): 685-695, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29878234

RESUMEN

Aberrant phosphorylation of the microtubule associated protein tau (tau) is associated with multiple neurodegenerative diseases where it is a contributes to neurotoxicity. We have observed that phosphorylation at Thr175 tau (pThr175 tau) exerts toxicity when expressed as a pseudophosphorylated tau construct (Thr175Asp) in vitro. To determine whether pThr175 tau can induce tau pathology in vivo with an accompanying clinical phenotype, we used a recombinant adenoviral expression vector (rAAV9) to express a GFP-tagged Thr175Asp tau protein construct in adult female Sprague-Dawley rat hippocampus. Ten rats per group were injected with rAAV9 vectors encoding either GFP, wild type GFP-tagged tau protein, Thr175Ala tau or Thr175Asp tau. 12 months postinjection, all rats were investigated by immunohistochemistry for GFP (extent of vector expression), pThr231 tau protein, activated GSK3ß, and caspase-3 cleavage. Vector expression was primarily localized to hippocampal CA2 subregion. Tau protein pathology restricted to the CA2 region in the form of axonal beading, fibrils, and neurofibrillary tangles was observed in Thr175Asp tau inoculated brains and included colocalization with pThr231 tau and caspase-3 cleavage in this group only. Although no behavioral or imaging phenotype was observed, our results demonstrate that pThr175 tau protein is capable of exerting neuronal toxicity in vivo.


Asunto(s)
Adenoviridae/metabolismo , Técnicas de Transferencia de Gen , Vectores Genéticos/metabolismo , Hipocampo/metabolismo , Treonina/metabolismo , Proteínas tau/metabolismo , Adenoviridae/genética , Animales , Femenino , Vectores Genéticos/genética , Hipocampo/patología , Humanos , Fosforilación/fisiología , Ratas , Ratas Sprague-Dawley , Reflejo de Sobresalto/fisiología , Treonina/genética , Proteínas tau/genética
12.
Acta Neuropathol Commun ; 5(1): 6, 2017 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-28077166

RESUMEN

Microtubule associated protein tau (tau) deposition is associated with a spectrum of neurodegenerative diseases collectively termed tauopathies. We have previously shown that amyotrophic lateral sclerosis (ALS) with cognitive impairment (ALSci) is associated with tau phosphorylation at Thr175 and that this leads to activation of GSK3ß which then induces phosphorylation at tau Thr231. This latter step leads to dissociation of tau from microtubules and pathological tau fibril formation. To determine the extent to which this pathway is unique to ALS, we have investigated the expression of pThr175 tau and pThr231 tau across a range of frontotemporal degenerations. Representative sections from the superior frontal cortex, anterior cingulate cortex (ACC), amygdala, hippocampal formation, basal ganglia, and substantia nigra were selected from neuropathologically confirmed cases of Alzheimer's disease (AD; n = 3), vascular dementia (n = 2), frontotemporal lobar degeneration (FTLD; n = 4), ALS (n = 5), ALSci (n = 6), Parkinson's disease (PD; n = 5), corticobasal degeneration (CBD; n = 2), diffuse Lewy body dementia (DLBD; n = 2), mixed DLBD (n = 3), multisystem atrophy (MSA; n = 6) and Pick's disease (n = 1) and three neuropathologically-normal control groups aged 50-60 (n = 6), 60-70 (n = 6) and 70-80 (n = 8). Sections were examined using a panel of phospho-tau antibodies (pSer208,210, pThr217, pThr175, pThr231, pSer202 and T22 (oligomeric tau)). Across diseases, phospho-tau load was most prominent in layers II/III of the entorhinal cortex, amygdala and hippocampus. This is in contrast to the preferential deposition of phospho-tau in the ACC and frontal cortex in ALSci. Controls showed pThr175 tau expression only in the 7th decade of life and only in the presence of tau pathology and tau oligomers. With the exception of DLBD, we observed pThr175 co-localizing with pThr231 in the same cell populations as T22 positivity. This suggests that this pathway may be a common mechanism of toxicity across the tauopathies.


Asunto(s)
Tauopatías/genética , Tauopatías/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Anciano , Anciano de 80 o más Años , Envejecimiento/metabolismo , Envejecimiento/patología , Encéfalo/metabolismo , Encéfalo/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroglía/metabolismo , Neuroglía/patología , Neuronas/metabolismo , Neuronas/patología , Fosforilación , Tauopatías/patología
13.
Neurobiol Aging ; 36(3): 1590-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25573097

RESUMEN

We have previously shown that amyotrophic lateral sclerosis with cognitive impairment can be characterized by pathologic inclusions of microtubule-associated protein tau (tau) phosphorylated at Thr(175) (pThr(175)) in association with GSK3ß activation. We have now examined whether pThr(175) induces GSK3ß activation and whether this leads to pathologic fibril formation through Thr(231) phosphorylation. Seventy-two hours after transfection of Neuro2A cells with pseudophosphorylated green fluorescent protein-tagged 2N4R tau (Thr(175)Asp), phosphorylated kinase glycogen synthase kinase 3 beta (active GSK3ß) levels were significantly increased as was pathologic fibril formation and cell death. Treatment with each of 4 GSK3ß inhibitors or small hairpin RNA knockdown of GSK3ß abolished fibril formation and prevented cell death. Inhibition of Thr(231) phosphorylation (Thr(231)Ala) prevented pathologic tau fibril formation, regardless of Thr(175) state, whereas Thr(231)Asp (pseudophosphorylated at Thr(231)) developed pathologic tau fibrils. Ser(235) mutations did not affect fibril formation, indicating an unprimed mechanism of Thr(231) phosphorylation. These findings suggest a mechanism of tau pathology by which pThr(175) induces GSK3ß phosphorylation of Thr(231) leading to fibril formation, indicating a potential therapeutic avenue for amyotrophic lateral sclerosis with cognitive impairment.


Asunto(s)
Glucógeno Sintasa Quinasa 3/metabolismo , Neurofibrillas/patología , Proteínas tau/metabolismo , Secuencias de Aminoácidos , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Esclerosis Amiotrófica Lateral/terapia , Muerte Celular/genética , Células Cultivadas , Biología Computacional , Técnicas de Silenciamiento del Gen , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3 beta , Células HEK293 , Humanos , Fosforilación , ARN Interferente Pequeño/genética , Tauopatías/genética , Tauopatías/patología , Tauopatías/terapia , Treonina/metabolismo , Proteínas tau/química
14.
BMC Res Notes ; 7: 298, 2014 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-24886343

RESUMEN

BACKGROUND: Parents of children with migraine have described a higher prevalence of sleep bruxism and other sleep disturbances in their children. The objective of this study was to use polysomnography to investigate the prevalence of bruxism during sleep in children with episodic migraine relative to controls. FINDINGS: Controls and patients were matched by sex, age, years of formal education, presence of snoring, arousals per hour, and respiratory events per hour.A total of 20 controls, between 6 and 12 years old, with no history of headache, recruited from public schools in Sao Paulo between 2009 and 2012, and 20 patients with episodic migraine recruited from the Headache Clinic at the Federal University of Sao Paulo between 2009 and 2012 underwent polysomnography.No intervention was performed before sleep studies.Among migraine patients, 27.5% experienced aura prior to migraine onset. The sleep efficiency, sleep latency, REM sleep latency, arousals per hour, percentage of sleep stages, and breathing events per hour were similar between groups. Five children (25%) with episodic migraine exhibited bruxism during the sleep study while this finding was not observed in any control (p = 0.045). CONCLUSIONS: Our data demonstrate that bruxism during sleep is more prevalent in children with episodic migraine. Further prospective studies will help elucidate the underlying shared pathogenesis between bruxism and episodic migraine in children.


Asunto(s)
Bruxismo/complicaciones , Bruxismo/epidemiología , Trastornos Migrañosos/complicaciones , Trastornos Migrañosos/epidemiología , Polisomnografía , Brasil/epidemiología , Bruxismo/fisiopatología , Estudios de Casos y Controles , Niño , Femenino , Humanos , Masculino , Trastornos Migrañosos/fisiopatología , Prevalencia , Sueño
15.
Einstein (Sao Paulo) ; 10(4): 428-32, 2012.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-23386081

RESUMEN

OBJECTIVE: To describe the prevalence and severity of periodic limb movements during sleep in amyotrophic lateral sclerosis patients and to explore this fact as a predictor of severity of the condition with respect to mortality. METHODS: In this case-control study, questionnaire and polysomnographic data were analyzed from 35 amyotrophic lateral sclerosis patients. Controls were matched by age, genre, and body mass index. A Kaplan-Meier curve was used to compare the survival time of patients with periodic limb movements of sleep index below or above 5. RESULTS: The number of amyotrophic lateral sclerosis patients with an index greater than five was higher than controls (19 (53%) versus 4 (11%); p < 0.0001), and the mean index was higher (23.55 ± 40.07 versus 3.28 ± 8.96; p = 0.0009). Earlier mortality was more common in patients with more than five periodic limb movements per hour of sleep than patients with less than five periodic limb movements per hour of sleep (7/19 (37%) versus 1/16 (6%); p = 0.04) in this group of patients that had a mean survival of 33 months. CONCLUSIONS: There were more periodic limb movements of sleep in amyotrophic lateral sclerosis patients than in the control population. The higher number of these movements in amyotrophic lateral sclerosis patients correlates with disease severity and may suggest poor survival.


Asunto(s)
Esclerosis Amiotrófica Lateral/mortalidad , Síndrome de Mioclonía Nocturna/epidemiología , Sueño , Anciano , Canadá/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Polisomnografía , Prevalencia , Índice de Severidad de la Enfermedad , Síndromes de la Apnea del Sueño/diagnóstico , Estadísticas no Paramétricas , Evaluación de Síntomas
17.
Einstein (Säo Paulo) ; 10(4): 428-432, Oct.-Dec. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-662466

RESUMEN

OBJECTIVE: To describe the prevalence and severity of periodic limb movements during sleep in amyotrophic lateral sclerosis patients and to explore this fact as a predictor of severity of the condition with respect to mortality. METHODS: In this case-control study, questionnaire and polysomnographic data were analyzed from 35 amyotrophic lateral sclerosis patients. Controls were matched by age, genre, and body mass index. A Kaplan-Meier curve was used to compare the survival time of patients with periodic limb movements of sleep index below or above 5. RESULTS: The number of amyotrophic lateral sclerosis patients with an index greater than five was higher than controls (19 (53%) versus 4 (11%); p<0.0001), and the mean index was higher (23.55±40.07 versus 3.28±8.96; p=0.0009). Earlier mortality was more common in patients with more than five periodic limb movements per hour of sleep than patients with less than five periodic limb movements per hour of sleep (7/19 (37%) versus 1/16 (6%); p=0.04) in this group of patients that had a mean survival of 33 months. CONCLUSIONS: There were more periodic limb movements of sleep in amyotrophic lateral sclerosis patients than in the control population. The higher number of these movements in amyotrophic lateral sclerosis patients correlates with disease severity and may suggest poor survival.


OBJETIVO:Descrever a prevalência e a severidade dos movimentos periódicos de membros durante o sono nos pacientes com esclerose lateral amiotrófica e explorar isso como um preditor de severidade da doença e mortalidade. MÉTODOS: Estudo caso controle em que foram analisados 35 pacientes por questionários e polissonografia. Os controles foram pareados por idade, gênero, e índice de massa corporal. Uma curva de Kaplan-Meier foi usada para comparar o tempo de sobrevida em pacientes com índice de movimento periódico de membros durante o sono acima e abaixo de 5. RESULTADOS: O número de pacientes com esclerose lateral amiotrófica com índice de movimentos periódicos de membros durante o sono acima de cinco foi maior do que os controles (19 (53%) versus 4 (11%); p<0,0001) e a média do índice de movimentos periódicos de membros durante o sono também foi maior no grupo dos pacientes (23,55±40,07 versus 3,28±8,96; p=0,0009). A mortalidade precoce foi mais comum em pacientes com mais que cinco movimentos durante o sono por hora do que pacientes com menos do que cinco movimentos durante o sono por hora (7/19 (37%) versus 1/16 (6%); p=0,04). Nesse grupo, os pacientes tiveram sobrevida média de 33 meses. CONCLUSÃO:Houve um maior número de movimentos periódicos de membros durante o sono em pacientes com esclerose lateral amiotrófica do que na população controle. O maior número de movimentos periódicos de membros durante o sono em pacientes com esclerose lateral amiotrófica foi correlacionado com severidade da doença e pode sugerir menor sobrevida.


Asunto(s)
Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Amiotrófica Lateral/mortalidad , Síndrome de Mioclonía Nocturna/epidemiología , Sueño , Estudios de Casos y Controles , Canadá/epidemiología , Estimación de Kaplan-Meier , Polisomnografía , Prevalencia , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Evaluación de Síntomas , Síndromes de la Apnea del Sueño/diagnóstico
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