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OBJECTIVE: Although astrocytic pathology is a pathological hallmark of progressive supranuclear palsy (PSP), its pathophysiological role remains unclear. This study aimed to assess astrocyte reactivity in vivo in patients with PSP. Furthermore, we investigated alterations in brain lactate levels and their relationship with astrocyte reactivity. METHODS: We included 30 patients with PSP-Richardson syndrome and 30 healthy controls; in patients, tau deposition was confirmed through 18F-florzolotau positron emission tomography. Myo-inositol, an astroglial marker, and lactate were quantified in the anterior cingulate cortex through magnetic resonance spectroscopy. We measured plasma biomarkers, including glial fibrillary acidic protein as another astrocytic marker. The anterior cingulate cortex was histologically assessed in postmortem samples of another 3 patients with PSP with comparable disease durations. RESULTS: The levels of myo-inositol and plasma glial fibrillary acidic protein were significantly higher in patients than those in healthy controls (p < 0.05); these increases were significantly associated with PSP rating scale and cognitive function scores (p < 0.05). The lactate level was high in patients, and correlated significantly with high myo-inositol levels. Histological analysis of the anterior cingulate cortex in patients revealed reactive astrocytes, despite mild tau deposition, and no marked synaptic loss. INTERPRETATION: We discovered high levels of astrocyte biomarkers in patients with PSP, suggesting astrocyte reactivity. The association between myo-inositol and lactate levels suggests a link between reactive astrocytes and brain energy metabolism changes. Our results indicate that astrocyte reactivity in the anterior cingulate cortex precedes pronounced tau pathology and neurodegenerative processes in that region, and affects brain function in PSP. ANN NEUROL 2024;96:247-261.
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Astrócitos , Proteína Glial Fibrilar Ácida , Giro do Cíngulo , Inositol , Ácido Láctico , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/metabolismo , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/patologia , Astrócitos/metabolismo , Astrócitos/patologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Glial Fibrilar Ácida/sangue , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Inositol/metabolismo , Giro do Cíngulo/metabolismo , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/patologia , Biomarcadores/sangue , Proteínas tau/metabolismo , Tomografia por Emissão de PósitronsRESUMO
OBJECTIVE: Increasing evidence suggests that reactive astrocytes are associated with Alzheimer's disease (AD). However, its underlying pathogenesis remains unknown. Given the role of astrocytes in energy metabolism, reactive astrocytes may contribute to altered brain energy metabolism. Astrocytes are primarily considered glycolytic cells, suggesting a preference for lactate production. This study aimed to examine alterations in astrocytic activities and their association with brain lactate levels in AD. METHODS: The study included 30 AD and 30 cognitively unimpaired participants. For AD participants, amyloid and tau depositions were confirmed by positron emission tomography using [11 C]PiB and [18 F]florzolotau, respectively. Myo-inositol, an astroglial marker, and lactate in the posterior cingulate cortex were quantified by magnetic resonance spectroscopy. These magnetic resonance spectroscopy metabolites were compared with plasma biomarkers, including glial fibrillary acidic protein as another astrocytic marker, and amyloid and tau positron emission tomography. RESULTS: Myo-inositol and lactate levels were higher in AD patients than in cognitively unimpaired participants (p < 0.05). Myo-inositol levels correlated with lactate levels (r = 0.272, p = 0.047). Myo-inositol and lactate levels were positively associated with the Clinical Dementia Rating sum-of-boxes scores (p < 0.05). Significant correlations were noted between myo-inositol levels and plasma glial fibrillary acidic protein, tau phosphorylated at threonine 181 levels, and amyloid and tau positron emission tomography accumulation in the posterior cingulate cortex (p < 0.05). INTERPRETATION: We found high myo-inositol levels accompanied by increased lactate levels in the posterior cingulate cortex in AD patients, indicating a link between reactive astrocytes and altered brain energy metabolism. Myo-inositol and plasma glial fibrillary acidic protein may reflect similar astrocytic changes as biomarkers of AD. ANN NEUROL 2023.
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AIM: To assess the association between plasma amyloid ß (Aß) 42/40, phosphorylated tau (p-τ)181, glial fibrillary acidic protein (GFAP), or neurofilament light chain (NfL) and the risk of dementia and to determine whether these plasma biomarkers could improve the ability to predict incident dementia in a general older population. METHODS: A total of 1346 Japanese community-dwelling individuals aged ≥65 years without dementia were followed prospectively for 5.0 years. Plasma biomarkers were quantified using a Simoa HD-X analyzer. A Cox proportional hazards model was used to estimate the hazard ratios of each plasma biomarker level for the risk of dementia. RESULTS: During the follow-up, 151 participants developed dementia, of whom 108 had Alzheimer disease (AD) and 43 non-Alzheimer dementia (non-AD). Lower plasma Aß42/40 levels and higher plasma p-τ181 levels were significantly associated with developing AD but not non-AD, whereas significant associations were observed between higher plasma levels of GFAP and NfL and risk of both AD and non-AD (all P for trend <0.05). In addition, adding these four plasma biomarkers into a model consisting of the total score of the dementia risk model significantly improved the predictive ability for incident dementia. CONCLUSION: Our findings suggest that plasma Aß42/40 and p-τ181 are specific markers of AD, and plasma GFAP and NfL are potential biomarkers for all-cause dementia in the general Japanese older population. In addition, the measurement of these plasma biomarkers may be a useful and relatively low-invasive procedure for identifying individuals at high risk for developing dementia in clinical practice.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Demência , Proteína Glial Fibrilar Ácida , Vida Independente , Proteínas de Neurofilamentos , Fragmentos de Peptídeos , Proteínas tau , Humanos , Idoso , Feminino , Masculino , Biomarcadores/sangue , Japão/epidemiologia , Demência/sangue , Demência/epidemiologia , Demência/diagnóstico , Peptídeos beta-Amiloides/sangue , Proteínas tau/sangue , Proteínas de Neurofilamentos/sangue , Fragmentos de Peptídeos/sangue , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Proteína Glial Fibrilar Ácida/sangue , Idoso de 80 Anos ou mais , Seguimentos , População do Leste AsiáticoRESUMO
BACKGROUND: We recently developed a positron emission tomography (PET) probe, [18 F]PM-PBB3, to detect tau lesions in diverse tauopathies, including mixed three-repeat and four-repeat (3R + 4R) tau fibrils in Alzheimer's disease (AD) and 4R tau aggregates in progressive supranuclear palsy (PSP). For wider availability of this technology for clinical settings, bias-free quantitative evaluation of tau images without a priori disease information is needed. OBJECTIVE: We aimed to establish tau PET pathology indices to characterize PSP and AD using a machine learning approach and test their validity and tracer capabilities. METHODS: Data were obtained from 50 healthy control subjects, 46 patients with PSP Richardson syndrome, and 37 patients on the AD continuum. Tau PET data from 114 regions of interest were subjected to Elastic Net cross-validation linear classification analysis with a one-versus-the-rest multiclass strategy to obtain a linear function that discriminates diseases by maximizing the area under the receiver operating characteristic curve. We defined PSP- and AD-tau scores for each participant as values of the functions optimized for differentiating PSP (4R) and AD (3R + 4R), respectively, from others. RESULTS: The discriminatory ability of PSP- and AD-tau scores assessed as the area under the receiver operating characteristic curve was 0.98 and 1.00, respectively. PSP-tau scores correlated with the PSP rating scale in patients with PSP, and AD-tau scores correlated with Mini-Mental State Examination scores in healthy control-AD continuum patients. The globus pallidus and amygdala were highlighted as regions with high weight coefficients for determining PSP- and AD-tau scores, respectively. CONCLUSIONS: These findings highlight our technology's unbiased capability to identify topologies of 3R + 4R versus 4R tau deposits. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Doença de Alzheimer , Transtornos dos Movimentos , Paralisia Supranuclear Progressiva , Tauopatias , Humanos , Proteínas tau/metabolismo , Encéfalo/patologia , Tauopatias/diagnóstico por imagem , Tauopatias/patologia , Paralisia Supranuclear Progressiva/patologia , Tomografia por Emissão de Pósitrons , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Aprendizado de MáquinaRESUMO
BACKGROUND AND PURPOSE: The aim was to investigate the association between serum asymmetric dimethylarginine (ADMA) levels and the progression and prognosis of amyotrophic lateral sclerosis (ALS), and to compare cerebrospinal fluid (CSF) and serum ADMA levels with other biomarkers of ALS. METHODS: Serum ADMA levels of sporadic ALS patients (n = 68), disease control patients (n = 54) and healthy controls (n = 20) were measured using liquid chromatography tandem mass spectrometry. Correlations of the ADMA level and other markers (nitric oxide and neurofilament light chain levels) were analyzed. Changes in the ALS Functional Rating Scale Revised (ALSFRS-R) score from the onset of disease (ALSFRS-R pre-slope) was used to assess disease progression. Survival was evaluated using the Cox proportional hazards model and Kaplan-Meier analysis. RESULTS: The serum ADMA level was substantially higher in patients with ALS than in healthy controls and disease controls. Serum ADMA level correlated with CSF ADMA level (r = 0.591, p < 0.0001) and was independently associated with the ALSFRS-R pre-slope (r = 0.505, p < 0.0001). Patients with higher serum ADMA levels had less favorable prognoses. CSF ADMA level significantly correlated with CSF neurofilament light chain level (r = 0.456, p = 0.0002) but not with nitric oxide level (r = 0.194, p = 0.219). CONCLUSION: Serum ADMA level is an independent biomarker of ALS disease progression and prognosis and reflects the degree of motor neuron degeneration.
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Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/diagnóstico , Arginina/análogos & derivados , Biomarcadores , Progressão da Doença , Humanos , Óxido Nítrico , PrognósticoRESUMO
There are a variety of neurodegenerative diseases that require differentiation from idiopathic normal pressure hydrocephalus(iNPH), including Alzheimer's disease, Parkinson's disease, dementia with Lewy bodies, frontotemporal dementia, progressive supranuclear palsy, and corticobasal degeneration. As the clinical features and structural imaging findings of these diseases may overlap with iNPH, biomarkers reflecting disease-specific pathology are necessary for differential diagnosis. In addition, these diseases often coexist with iNPH in elderly patients, and it is important to confirm the coexistence of their pathology even in cases clinically diagnosed as iNPH. This review provides an overview of established and emerging biomarkers for neurodegenerative diseases.
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Hidrocefalia de Pressão Normal , Doenças Neurodegenerativas , Doença de Parkinson , Idoso , Biomarcadores , Diagnóstico Diferencial , Humanos , Hidrocefalia de Pressão Normal/complicações , Hidrocefalia de Pressão Normal/diagnóstico , Hidrocefalia de Pressão Normal/patologia , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/diagnóstico , Doença de Parkinson/diagnósticoRESUMO
BACKGROUND: Tangible efforts have been made to identify biomarkers for Parkinson's disease (PD) diagnosis and progression, with α-synuclein (α-syn) related biomarkers being at the forefront. OBJECTIVES: The objectives of this study were to explore whether cerebrospinal fluid (CSF) levels of total, oligomeric, phosphorylated Ser 129 α-synuclein, along with total tau, phosphorylated tau 181, and ß-amyloid 1-42 are (1) informative as diagnostic markers for PD, (2) changed over disease progression, and/or (3) correlated with motor and cognitive indices of disease progression in the longitudinal De Novo Parkinson cohort. METHODS: A total of 94 de novo PD patients and 52 controls at baseline and 24- and 48-month follow-up were included, all of whom had longitudinal lumbar punctures and clinical assessments for both cognitive and motor functions. Using our in-house enzymelinked immunosorbent assays and commercially available assays, different forms of α-synuclein, tau, and ß-amyloid 1-42 were quantified in CSF samples from the De Novo Parkinson cohort. RESULTS: Baseline CSF total α-synuclein was significantly lower in early de novo PD compared with healthy controls, whereas the ratio of oligomeric/total and phosphorylated/total were significantly higher in the PD group. CSF oligomeric-α-synuclein longitudinally increased over the 4-year follow-up in the PD group and correlated with PD motor progression. Patients at advanced stages of PD presented with elevated CSF oligomeric-α-synuclein levels compared with healthy controls. CONCLUSIONS: Longitudinal transitions of CSF biomarkers over disease progression might not occur linearly and are susceptible to disease state. CSF oligomeric-α-synuclein levels appear to increase with diseases severity and reflect PD motor rather than cognitive trajectories. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Doença de Parkinson , alfa-Sinucleína , Peptídeos beta-Amiloides , Estudos de Coortes , Humanos , Fragmentos de PeptídeosRESUMO
BACKGROUND AND AIM: Toxic oligomeric α-synuclein (αS; O-αS) has been suggested to play a central role in the pathogenesis of Lewy body diseases such as Parkinson's disease (PD). Cerebrospinal fluid (CSF) levels of αS, O-αS, total and phosphorylated tau, and amyloid ß 1-42 (Aß1-42) are thought to reflect the pathophysiology or clinical symptoms in PD. In this study, we examined correlations of the CSF levels of these proteins with the clinical symptoms, and with each other in drug-naïve patients with PD. METHODS: Twenty-seven drug-naïve patients with PD were included. Motor and cognitive functions were assessed using the Unified Parkinson's Disease Rating Scale (UPDRS), Montreal Cognitive Assessment (MoCA), and Neurobehavioral Cognitive Status Examination (COGNISTAT). CSF levels of total αS, O-αS, Aß1-42, total tau and tau phosphorylated at threonine 181 (P-tau181p) were measured. CSF levels of these proteins were compared with clinical assessments from the UPDRS, MoCA and COGNISTAT using Spearman correlation analysis. Spearman correlation coefficients among CSF protein levels were also evaluated. RESULTS: CSF levels of αS were negatively correlated with UPDRS part III (motor score) (p < 0.05) and bradykinesia (p < 0.01), and positively correlated with COGNISTAT subtest of judgement (p < 0.01) and CSF levels of Aß1-42 (p < 0.001), total tau (p < 0.001) and P-tau181p (p < 0.01). Lower CSF levels of Aß1-42, total tau and P-tau181p were significantly related to worsening of some motor and/or cognitive functions. The CSF level of O-αS showed no correlation with any motor and cognitive assessments or with CSF levels of the other proteins. CONCLUSION: CSF levels of αS are correlated with some clinical symptoms and CSF levels of other pathogenic proteins in drug-naïve PD patients. These correlations suggest a central role for interaction and aggregation of αS with Aß1-42, tau, and phosphorylated tau in the pathogenesis of PD. Although O-αS has been shown to have neurotoxic effects, CSF levels do not reflect clinical symptoms or levels of other proteins in cross-sectional assessment.
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Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Doença de Parkinson/líquido cefalorraquidiano , alfa-Sinucleína/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologiaRESUMO
PURPOSE: The purpose of this study was to elucidate the specific regional cerebral blood flow (rCBF) alterations for idiopathic normal pressure hydrocephalus (iNPH) by comparing the proportional rCBF and gray matter change from those of a normal database at the same point of SPECT and MRI examinations. METHODS: Thirty subjects with iNPH underwent both CBF SPECT and MRI. After normalization, voxel-wise two-sample t tests between patients and 11 normal controls were conducted to compare the regional alteration in the gray matter density and rCBF. RESULTS: The rCBF reduction and the gray matter decrease were seen in almost similar regions surrounding Sylvian fissure, the left parietotemporal region and frontal lobes, whereas we did not find rCBF increase at the top of the high convexity, where the increase of the gray matter density was the highest (p < 0.05). CONCLUSION: Our study showed regional associations and dissociations between the relative gray matter density and rCBF in patients with iNPH.
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Circulação Cerebrovascular , Substância Cinzenta/diagnóstico por imagem , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Fluxo Sanguíneo Regional , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Idoso de 80 Anos ou mais , Feminino , Substância Cinzenta/patologia , Humanos , Hidrocefalia de Pressão Normal/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
Mutations in the Fused in Sarcoma (FUS) gene have been identified in familial ALS in human. Drosophila contains a single ortholog of human FUS called Cabeza (Caz). We previously established Drosophila models of ALS targeted to Caz, which developed the locomotive dysfunction and caused anatomical defects in presynaptic terminals of motoneurons. Accumulating evidence suggests that ALS and cancer share defects in many cellular processes. The Hippo pathway was originally discovered in Drosophila and plays a role as a tumor suppressor in mammals. We aimed to determine whether Hippo pathway genes modify the ALS phenotype using Caz knockdown flies. We found a genetic link between Caz and Hippo (hpo), the Drosophila ortholog of human Mammalian sterile 20-like kinase (MST) 1 and 2. Loss-of-function mutations of hpo rescued Caz knockdown-induced eye- and neuron-specific defects. The decreased Caz levels in nuclei induced by Caz knockdown were also rescued by loss of function mutations of hpo. Moreover, hpo mRNA level was dramatically increased in Caz knockdown larvae, indicating that Caz negatively regulated hpo. Our results demonstrate that hpo, Drosophila MST, is a novel modifier of Drosophila FUS. Therapeutic targets that inhibit the function of MST could modify the pathogenic processes of ALS.
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Proteínas de Ciclo Celular/genética , Proteínas do Citoesqueleto/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Larva/genética , Neurogênese/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas de Ligação a RNA/genética , Fator de Transcrição TFIID/genética , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Proteínas de Ciclo Celular/metabolismo , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Olho/metabolismo , Olho/ultraestrutura , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Larva/citologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Degeneração Neural , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/ultraestrutura , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Fator de Transcrição TFIID/deficiênciaRESUMO
BACKGROUND AND PURPOSE: We previously reported the usefulness of iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy for differentiation of dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) in a cross-sectional multicentre study. The aim of this study was, by using reassessed diagnosis after 3-year follow-up, to evaluate the diagnostic accuracy of 123I-MIBG scintigraphy in differentiation of probable DLB from probable AD. METHODS: We undertook 3-year follow-up of 133 patients with probable or possible DLB or probable AD who had undergone 123I-MIBG myocardial scintigraphy at baseline. An independent consensus panel made final diagnosis at 3-year follow-up. Based on the final diagnosis, we re-evaluated the diagnostic accuracy of 123I-MIBG scintigraphy performed at baseline. RESULTS: Sixty-five patients completed 3-year follow-up assessment. The final diagnoses were probable DLB (n=30), possible DLB (n=3) and probably AD (n=31), and depression (n=1). With a receiver operating characteristic curve analysis of heart-to-mediastinum (H/M) ratios for differentiating probable DLB from probable AD, the sensitivity/specificity were 0.77/0.94 for early images using 2.51 as the threshold of early H/M ratio, and 0.77/0.97 for delayed images using 2.20 as the threshold of delayed H/M ratio. Five of six patients who were diagnosed with possible DLB at baseline and with probable DLB at follow-up had low H/M ratio at baseline. CONCLUSIONS: Our follow-up study confirmed high correlation between abnormal cardiac sympathetic activity evaluated with 123I-MIBG myocardial scintigraphy at baseline and the clinical diagnosis of probable DLB at 3-year follow-up. Its diagnostic usefulness in early stage of DLB was suggested. TRIAL REGISTRATION NUMBER: UMIN00003419.
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3-Iodobenzilguanidina , Doença de Alzheimer/diagnóstico por imagem , Doença por Corpos de Lewy/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Masculino , Sensibilidade e EspecificidadeRESUMO
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects upper and lower motor neurons in the brain and the spinal cord. Due to the progressive neurodegeneration, ALS leads to paralysis and death caused by respiratory failure 2-5 years after the onset of symptoms. There is no effective cure available. Most ALS cases are sporadic, without family history, whereas 10% of the cases are familial. Identification of variants in more than 30 different loci has provided insight into the pathogenic molecular mechanisms mediating disease pathogenesis. Studies of a Drosophila melanogaster model for each of the ALS genes can contribute to uncovering pathophysiological mechanism of ALS and finding targets of the disease-modifying therapy. In this review, we focus on three ALS-causing genes: TAR DNA-binding protein (TDP-43), fused in sarcoma/translocated in liposarcoma (FUS/TLS), and chromosome 9 open reading frame 72 (C9orf72).
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Esclerose Lateral Amiotrófica , Modelos Animais de Doenças , Drosophila melanogaster , Animais , HumanosRESUMO
In humans, mutations in the fused in sarcoma (FUS) gene have been identified in sporadic and familial forms of amyotrophic lateral sclerosis (ALS). Cabeza (Caz) is the Drosophila ortholog of human FUS. Previously, we established Drosophila models of ALS harboring Caz-knockdown. These flies develop locomotive deficits and anatomical defects in motoneurons (MNs) at neuromuscular junctions; these phenotypes indicate that loss of physiological FUS functions in the nucleus can cause MN degeneration similar to that seen in FUS-related ALS. Here, we aimed to explore molecules that affect these ALS-like phenotypes of our Drosophila models with eye-specific and neuron-specific Caz-knockdown. We examined several previously reported ALS-related genes and found genetic links between Caz and ter94, the Drosophila ortholog of human Valosin-containing protein (VCP). Genetic crossing the strongest loss-of-function allele of ter94 with Caz-knockdown strongly enhanced the rough-eye phenotype and the MN-degeneration phenotype caused by Caz-knockdown. Conversely, the overexpression of wild-type ter94 in the background of Caz-knockdown remarkably suppressed those phenotypes. Our data demonstrated that expression levels of Drosophila VCP ortholog dramatically modified the phenotypes caused by Caz-knockdown in either direction, exacerbation or remission. Our results indicate that therapeutic agents that up-regulate the function of human VCP could modify the pathogenic processes that lead to the degeneration of MNs in ALS.
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Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Neurônios Motores/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fator de Transcrição TFIID/metabolismo , Animais , Animais Geneticamente Modificados , Proteínas de Ciclo Celular/genética , Sistema Nervoso Central/citologia , Sistema Nervoso Central/metabolismo , Olho Composto de Artrópodes/metabolismo , Olho Composto de Artrópodes/patologia , Drosophila , Proteínas de Drosophila/genética , Mutação , Proteína FUS de Ligação a RNA/genética , Proteínas de Ligação a RNA/genética , Fator de Transcrição TFIID/genética , Proteína com ValosinaRESUMO
BACKGROUND: Parkinson's disease (PD) diagnosis is mainly based on clinical criteria, with a high risk of misdiagnosis. The identification of reliable biomarkers for disease diagnosis and progression has a key role for developing disease-modifying therapies. In this article, we investigated the longitudinal changes of CSF α-synuclein species in early PD patients and explored the potential use of these species as surrogate biomarkers for PD progression. METHODS: We used our newly developed enzyme-linked immunosorbent assay systems for measuring different forms of α-synuclein, such as oligomeric-α-synuclein, phosphorylated-α-synuclein at serine 129, or total-α-synuclein in CSF from the longitudinal Deprenyl and Tocopherol Antioxidative Therapy for Parkinsonism study cohort (n = 121). CSF Alzheimer's disease biomarkers (total-tau, phosphorylated-tau, Aß40 , and Aß42 ) were also measured for this cohort. RESULTS: Interestingly, total-α-synuclein and oligomeric-α-synuclein levels significantly increased during the 2-year Deprenyl and Tocopherol Antioxidative Therapy for Parkinsonism study follow-up period, whereas phosphorylated-α-synuclein at serine 129 levels showed a longitudinal decrease. We have also noted an association between a change of the oligomeric-α-synuclein/total-α-synuclein ratio and a worsening of motor signs, in particular in the postural-instability and gait-difficulty dominant PD group. A strong positive correlation between the changes in CSF total-α-synuclein and oligomeric-α-synuclein during the 2-year Deprenyl and Tocopherol Antioxidative Therapy for Parkinsonism study was also noted (r = 0.84, P < .001). CONCLUSION: Our data show that CSF α-synuclein species have a dynamic pattern along the course of the disease, supporting their possible role as progression biomarkers for PD and their link with PD clinical phenotypes. © 2016 International Parkinson and Movement Disorder Society.
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Progressão da Doença , Doença de Parkinson/líquido cefalorraquidiano , alfa-Sinucleína/líquido cefalorraquidiano , Idoso , Antioxidantes/uso terapêutico , Biomarcadores/líquido cefalorraquidiano , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológicoRESUMO
BACKGROUND: Recent research suggests that several pathogenetic factors, including aging, genetics, inflammation, dyslipidemia, diabetes, and infectious diseases, influence cognitive decline (CD) risk. However, no definitive candidate causes have been identified. The present study evaluated whether certain serum parameters predict CD. METHODS: A total of 151 participants were assessed for CD using the Mini-Mental State Examination (MMSE), and 34 participants were identified as showing CD. RESULTS: Among CD predictive risk factors, Helicobacter pylori seropositivity was significantly predictive of CD risk, more so than classical risk factors, including white matter lesions and arterial stiffness [adjusted odds ratio (OR) = 4.786, 95% confidence interval (CI) = 1.710-13.39]. A multivariate analysis indicated that the albumin to globulin (A/G) ratio was the only factor that significantly lowered CD risk (OR = 0.092, 95% CI = 0.010-0.887). A/G ratio also was positively correlated with MMSE scores and negatively correlated with disruption of homeostatic factors (i.e., non-high-density lipoprotein, hemoglobin A1c, and high-sensitive C-reactive protein). CONCLUSIONS: The current study results suggest that the A/G ratio is related to cognitive decline and may reflect homeostatic alterations.
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Disfunção Cognitiva/sangue , Globulinas/metabolismo , Albumina Sérica/metabolismo , Idoso , Envelhecimento/psicologia , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Feminino , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de RiscoRESUMO
The formation of intracellular aggregates containing α-synuclein (α-Syn) is one of the key steps in the progression of Parkinson's disease and dementia with Lewy bodies. Recently, it was reported that pathological α-Syn fibrils can undergo cell-to-cell transmission and form Lewy body-like aggregates. However, little is known about how they form α-Syn aggregates from fibril seeds. Here, we developed an assay to study the process of aggregate formation using fluorescent protein-tagged α-Syn-expressing cells and examined the aggregate forming activity of exogenous α-Syn fibrils. α-Syn fibril-induced formation of intracellular aggregates was suppressed by a cathepsin B specific inhibitor, but not by a cathepsin D inhibitor. α-Syn fibrils pretreated with cathepsin B in vitro enhanced seeding activity in cells. Knockdown of cathepsin B also reduced fibril-induced aggregate formation. Moreover, using LAMP-1 immunocytochemistry and live-cell imaging, we observed that these aggregates initially occurred in the lysosome. They then rapidly grew larger and moved outside the boundary of the lysosome within one day. These results suggest that the lysosomal protease cathepsin B is involved in triggering intracellular aggregate formation by α-Syn fibrils.
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Catepsina B/metabolismo , Lisossomos/metabolismo , Agregação Patológica de Proteínas/metabolismo , alfa-Sinucleína/metabolismo , Amiloide/metabolismo , Catepsina B/antagonistas & inibidores , Catepsina D/metabolismo , HumanosRESUMO
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease that causes progressive muscular weakness. Fused in Sarcoma (FUS) that has been identified in familial ALS is an RNA binding protein that is normally localized in the nucleus. However, its function in vivo is not fully understood. Drosophila has Cabeza (Caz) as a FUS homologue and specific knockdown of Caz in the eye imaginal disc and pupal retina using a GMR-GAL4 driver was here found to induce an abnormal morphology of the adult compound eyes, a rough eye phenotype. This was partially suppressed by expression of the apoptosis inhibitor P35. Knockdown of Caz exerted no apparent effect on differentiation of photoreceptor cells. However, immunostaining with an antibody to Cut that marks cone cells revealed fusion of these and ommatidia of pupal retinae. These results indicate that Caz knockdown induces apoptosis and also inhibits differentiation of cone cells, resulting in abnormal eye morphology in adults. Mutation in EGFR pathway-related genes, such as rhomboid-1, rhomboid-3 and mirror suppressed the rough eye phenotype induced by Caz knockdown. Moreover, the rhomboid-1 mutation rescued the fusion of cone cells and ommatidia observed in Caz knockdown flies. The results suggest that Caz negatively regulates the EGFR signaling pathway required for determination of cone cell fate in Drosophila.
Assuntos
Animais Geneticamente Modificados/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Receptores ErbB/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteína FUS de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Receptores de Peptídeos de Invertebrados/metabolismo , Retina/metabolismo , Fator de Transcrição TFIID/metabolismo , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Apoptose , Western Blotting , Diferenciação Celular , Drosophila/genética , Drosophila/crescimento & desenvolvimento , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/genética , Receptores ErbB/genética , Feminino , Técnicas Imunoenzimáticas , Masculino , Microscopia Eletrônica de Varredura , RNA Interferente Pequeno/genética , Proteína FUS de Ligação a RNA/genética , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/genética , Receptores de Peptídeos de Invertebrados/genética , Retina/citologia , Transdução de Sinais , Fator de Transcrição TFIID/antagonistas & inibidores , Fator de Transcrição TFIID/genéticaRESUMO
INTRODUCTION: In this study we aimed to clarify whether muscle ultrasound (US) of the forearm can be used to differentiate between patients with sporadic inclusion body myositis (s-IBM) and those with s-IBM-mimicking diseases. METHODS: We compared the echo intensity (EI) of the flexor digitorum profundus (FDP) muscle and the flexor carpi ulnaris (FCU) muscles in patients with s-IBM (n = 6), polymyositis/dermatomyositis (PM/DM; n = 6), and amyotrophic lateral sclerosis (ALS; n = 6). RESULTS: We identified EI abnormalities in 100% of patients with s-IBM, 33% of those with PM/DM, and 33% of those with ALS. An "FDP-FCU echogenicity contrast," a US pattern involving a higher EI in the FDP than in the FCU, was observed in all patients with s-IBM, but in none of those with PM/DM or ALS. CONCLUSIONS: FDP-FCU echogenicity contrast in muscle US is a sensitive diagnostic indicator of s-IBM.
Assuntos
Esclerose Lateral Amiotrófica/diagnóstico por imagem , Dermatomiosite/diagnóstico por imagem , Antebraço/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Miosite de Corpos de Inclusão/diagnóstico por imagem , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , UltrassonografiaRESUMO
BACKGROUND: Immune globulin intravenous (IGIV), 10% is a donor-derived polyclonal human immunoglobulin G antibody mixture that has potent immune modulatory properties and contains conformation selective anti-amyloid antibodies. We evaluated the safety and tolerability of multiple doses of IGIV, 10% in Japanese patients with mild to moderate Alzheimer's disease. METHODS: Among the 16 subjects, 12 subjects were assigned to the IGIV group and 4 subjects to the placebo group. Subjects received a total of six infusions of either IGIV at a dose of 0.2 or 0.4 g/kg, or placebo every 2 weeks. RESULTS: A total of 33 treatment-emergent adverse events (TEAE) occurred in 14 subjects: 13 TEAE in five subjects in both the IGIV 0.2 and 0.4 g/kg groups, and 7 TEAE in four subjects in the placebo group. The most common TEAE in the IGIV subjects were nasopharyngitis, injection-site swelling, and erythema. All 26 TEAE in the IGIV group were considered to be mild. Only one mild TEAE (rash) was considered to be possibly related to the study drug. There were no significant differences in incidence of TEAE between the treatment groups. Four serious TEAE were reported, and all of these were considered to be unrelated to the study treatment. Other assessments related to safety revealed neither clinically significant abnormal values nor findings in the study. CONCLUSION: IGIV is generally safe and well tolerated with multiple intravenous infusions at doses of 0.2 g/kg and 0.4 g/kg in Japanese patients with mild to moderate Alzheimer's disease.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Imunoglobulinas Intravenosas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Doença de Alzheimer/diagnóstico , Povo Asiático , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Imunoglobulinas Intravenosas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
The level of TAR DNA-binding protein 43 (TDP-43) in human blood was reported to have potential for use as a specific fluid biomarker, which represents disease-specific pathologies, for TDP-43 proteinopathies, including amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), which involves the aggregation and deposition of TDP-43 in the nervous system. However, at present, no reliable immunoassay can precisely quantify TDP-43 in human plasma and detect the difference in plasma TDP-43 levels between patients with ALS and controls. We recently developed a novel ultrasensitive immunoassay to quantify TDP-43 in human plasma, and in this study, we analytically validated this assay for application as a diagnostic biomarker for TDP-43 proteinopathies. The novel TDP-43 assay was assessed for the limit of detection, lower limit of quantification, intra- and interassay variation, linearity, parallelism, and analytical spike recoveries. Additionally, 17 pilot plasma samples obtained from patients with ALS and age-matched controls were analyzed using the assay. Our novel TDP-43 assay showed sufficient analytical performance to quantify TDP-43 in human plasma, with high sensitivity (LOD and LLOQ of 0.109 and 0.759 pg/mL, respectively) and high intra- and interassay precision (%CV) below 15 %. The experimental results for spike recovery, parallelism, and dilution linearity were also acceptable. In addition, despite a small sample size, significant differences in the plasma levels of TDP-43 were found between patients with ALS and controls (ALS, 66.63 ± 20.52 pg/mL; control, 42.70 ± 23.06 pg/mL, p = 0.0330). These results support that our novel TDP-43 assay is a reliable and innovative method for the quantification of TDP-43 in human plasma and can be a potential blood-based biomarker for the diagnosis of TDP-43 proteinopathies. Further large-scale studies are warranted to validate its usefulness.