American journal of neurodegenerative disease最新文献

There is a lack of validated tools for assessing Alzheimer's disease (AD) across Asia. This study evaluates the psychometric properties of the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), Disability Assessment for Dementia (DAD), and Neuropsychological Test Battery (NTB) in Asian participants. Participants with mild to moderate AD (n=251) and healthy controls (n=51) from Mainland China, Taiwan, Singapore, Hong Kong, and South Korea completed selected instruments at several time points. Test-retest reliability was better than 0.70 for all tests. AD participants performed significantly more poorly than controls on every score. Within the AD group, greater disease severity corresponded to significantly poorer performance. The AD group test performance worsened over time and there was a trend for worse performance in AD compared to healthy controls over time. The ADAS-Cog, DAD, and NTB are reliable, valid, and responsive measures in this population and could be used for clinical trials across Asian countries/regions.

Amyloid deposition has been implicated as the key determinant of Alzheimer's disease (AD) pathogenesis. Interventions to antagonize amyloid accumulation and mitigate dementia are now under active investigation. We conducted a combined clinical, biochemical and neuropathological assessment of a participant in a clinical trial of the γ-secretase inhibitor, semagacestat. This patient received a daily oral dose of 140 mg of semagacestat for approximately 76 weeks. Levels of brain amyloid-β (Aβ) peptides were quantified using enzyme-linked immunosorbent assays (ELISA). Western blot/scanning densitometry was performed to reveal BACE1, presenilin1, amyloid precursor protein (APP) and its proteolysis-produced C-terminal peptides APP-CT99 and APP-CT83 as well as several γ-secretase substrates. To serve as a frame of reference, the ELISA and Western analyses were performed in parallel on samples from neuropathologically confirmed non-demented control (NDC) and AD subjects who did not receive semagacestat. Neuropathology findings confirmed a diagnosis of AD with frequent amyloid deposits and neurofibrillary tangles in most areas of the cortex and subcortical nuclei as well as cerebellar amyloid plaques. Mean levels of Tris-soluble Aβ40 and glass-distilled formic acid (GDFA)/guanidine hydrochloride (GHCl)-extractable Aβ40 in the frontal lobe and GDFA/GHCl-soluble Aβ40 in the temporal lobe were increased 4.2, 9.5 and 7.7-fold, respectively, in the semagacestat-treated subject compared to those observed in the non-treated AD group. In addition, GDFA/GHCl-extracted Aβ42 was increased 2-fold in the temporal lobe relative to non-treated AD cases. No major changes in APP, β- and γ-secretase and CT99/CT83 were observed between the semagacestat-treated subject compared to either NDC or AD cases. Furthermore, the levels of γ-secretase substrates in the semagacestat-treated subject and the reference groups were also similar. Interestingly, there were significant alterations in the levels of several γ-secretase substrates between the NDC and non-treated AD subjects. This is the first reported case study of an individual enrolled in the semagacestat clinical trial. The subject of this study remained alive for ~7 months after treatment termination, therefore it is difficult to conclude whether the outcomes observed represent a consequence of semagacestat therapy. Additional evaluations of trial participants, including several who expired during the course of treatment, may provide vital clarification regarding the impacts and aftermath of γ-secretase inhibition.

Introduction: Biomarkers represent a promising adjunct to clinical techniques in the diagnosis of Alzheimer's Disease (AD) and other neurodegenerative diseases. At present, the potential of cerebrospinal fluid (CSF) biomarkers in diagnosing AD has been suggested but the degree of clinical utility is yet to be defined due to variability between studies. In this paper we compare the performance of two cerebrospinal fluid assay methods in predicting clinically diagnosed AD.

Methods: CSF biomarker concentrations for Aβ1-42, P-tau181P and T-tau were analysed using INNOTEST (ELISA) and INNO-BIA AlzBio3 (Luminex) assay methods from Innogenetics, Belgium. Patients were clinically diagnosed based on NINCDS-ADRDA criteria supplemented with structural MRI, (18)F-fluorodeoxy-glucose positron emission tomography (FDG-PET) and cognitive profiling.

Results: An abnormally low Aβ1-42 was the most useful biomarker in predicting clinical AD. Depending on the assay method, the predictive accuracy remained constant or improved slightly when abnormalities in P-tau181P and T-tau were considered in addition to Aβ1-42. The Luminex method with our optimised reference concentrations performed best for patients ≤ 65 years with sensitivity = 1 and a specificity = 0.60 for both Aβ1-42 and when one or more abnormal biomarkers were considered.

Conclusion: Given accurate, robust and reproducible CSF analytical methods, of which the Luminex method seems the most useful and practicable, our investigation suggests that measuring CSF Aβ1-42, P-tau and T-tau has utility in the diagnosis of probable AD and, when used with clinical diagnostic techniques, seems especially helpful in the diagnosis of AD with onset prior to the age of 65 years.

Previous studies have shown a selective reduction of von Economo neurons (VENs) in behavioral variant frontotemporal dementia (bvFTD). However, the alleged selectivity rests on the comparison between VENs and other neurons in cortical layer V, while it has been established that neurons in the superficial cortical layers (I-III) are particularly affected in bvFTD. The purpose of this study was to examine loss the loss of VENs in comparison with that of non-VEN-neurons of superficial cortical layers. VENs and non-VEN-neurons of cortical layer V and layers II+III were quantified in the anterior cingulate cortex in 16 cases of bvFTD, 12 non-demented controls and 10 cases of Alzheimer's disease (AD). In bvFTD VENs were more depleted than non-VEN-neurons of layers V and II+III. Also, non-VEN-neurons of layer II+III showed a greater density reduction than those of layer V in bvFTD. VEN density was also reduced in AD, albeit to a lesser extent than in bvFTD, and the differences between bvFTD and AD were only significant when relating VEN loss to that of layer V neurons. Our study strengthens the view of VENs as a particularly sensitive neuronal type of bvFTD, and appears to be on a continuum with the loss of other neurons both in bvFTD and between conditions.

Up to date, almost all researchers consider that there is still no effective therapy for neurodegenerative diseases (NDDs) and therefore, these diseases are incurable. However, since May 1998, we know that a progressive ischemia in the medial temporal lobes and subcommissural regions can cause Alzheimer's disease; because, in contrast to this, its revascularization by means of omental tissue can cure or improve this disease. Likewise we observed that the aging process, Huntington's disease, Parkinson's disease, and Amyotrophic lateral sclerosis; all of them are of ischemic origin caused by cerebral atherosclerosis, associated with vascular anomalies and/or environmental chemicals. On the contrary, an omental transplantation on the affected zone can stop and improve these diseases. For these reasons, I believe that NDDs, are wrongly classified as neurodegenerative disorders.

Background: Alzheimer's disease (AD) is the most common cause of dementia in older patients. Rivastigmine, a reversible cholinesterase inhibitor, has been shown to improve the clinical manifestations of AD by delaying the breakdown of acetylcholine (ACh) released into synaptic clefts. Moreover, there is evidence that ACh modulates EEG alpha frequency.

Objectives: the objectives of this pilot study in patients with AD were to determine the effects of two formulations of RV (transdermal and oral) on Mini-Mental State Examination (MMSE) scores and on alpha frequency in particular the posterior dominant rhythm.

Methods: twenty subjects with AD were randomly assigned to receive either RV transdermal patch (RV-TDP, n=10) or RV capsules (RV-CP, n=10) according to the standard recommended dosage regimen. All patients were driven to the maximum drug dosage. Diagnosis of AD was made according to NINCDS-ADRDA criteria and the Diagnostic and Statistical Manual of Mental Disorders IV. All patients underwent EEG recordings at the beginning and at the end of the 18-month study period using P3, P4, O1 and O2 electrodes each at high (10.5-13.0 Hz) and low (8.0-10.5 Hz) frequency. MMSE scores were determined at the start of the study and at three successive 6-month intervals (T0, T1, T2, and T3).

Results: administration of RV-DP increases the spectral power of alpha waves in the posterior region and is associated with improved cognitive function as evidenced by significant changes in MMSE scores.

Conclusion: RV-DP provides an effective and long-term management option in patients with AD.

Optineurin (OPTN) is a multifunctional protein involved in cellular morphogenesis, vesicle trafficking, maintenance of the Golgi complex, and transcription activation through its interactions with the Rab8, myosin 6 (MYO6), huntingtin. Recently, OPTN immunoreactivity has been reported in intranuclear inclusions in patients with neuronal intranuclear inclusions disease (NIID). Other studies have shown that the RNA-binding protein, fused in sarcoma (FUS), is a component of intranuclear inclusions in NIID. We aimed to investigate the relationship between OPTN, its binding protein MYO6 and FUS in this study. In control subjects, OPTN (C-terminal) (OPTN-C) and MYO6 immunoreactivity was mainly demonstrated in the cytoplasm of neurons. In NIID patients, both neuronal intranuclear inclusions (NII) and glial intranuclear inclusions (GII) were immunopositive for MYO6 as well as OPTN-C. However, the intensity of OPTN-C immunostaining of the neuronal cytoplasm with and without NII was less than that of the control subjects. Double immunofluorescence staining for OPTN-C, ubiquitin (Ub), p62 and FUS revealed co-localization of these proteins within NII. Moreover, Ub positive inclusions were co-localized with MYO6. The percentage of co-localization of Ub with OPTN-C, FUS or MYO6 in NII was 100%, 52% and 92%, respectively. Ultrastructurally, the inclusions consisted of thin and thick filaments. Both filaments were immunopositive for Ub and OPTN-C. These findings suggest that OPTN plays a central role in the disease pathogenesis, and that OPTN may be a major component of NII.

Frontotemporal dementia (FTD) is associated with a broad spectrum of clinical characteristics. The objective of this study was to analyze the prevalence of unexplained somatic complaints in neuropathologically verified FTD. We also examined whether the somatic presentations correlated with protein pathology or regional brain pathology and if the patients with these somatic features showed more depressive traits. Ninety-seven consecutively neuropathologically verified FTLD patients were selected. All 97 patients were part of a longitudinal study of FTD and all medical records were systematically reviewed. The somatic complaints focused on were headache, musculoskeletal, gastro/urogenital and abnormal pain response. Symptoms of somatic character (either somatic complaints and/or abnormal pain response) were found in 40.2%. These patients did not differ from the total group with regard to gender, age at onset or duration. Six patients showed exaggerated reactions to sensory stimuli, whereas three patients showed reduced response to pain. Depressive traits were present in 38% and did not correlate with somatic complaints. Suicidal behavior was present in 17 patients, in 10 of these suicidal behavior was concurrent with somatic complaints. No clear correlation between somatic complaints and brain protein pathology, regional pathology or asymmetric hemispherical atrophy was found. Our results show that many FTD patients suffer from unexplained somatic complaints before and/or during dementia where no clear correlation can be found with protein pathology or regional degeneration. Somatic complaints are not covered by current diagnostic criteria for FTD, but need to be considered in diagnostics and care. The need for prospective studies with neuropathological follow up must be stressed as these phenomena remain unexplained, misinterpreted, bizarre and, in many cases, excruciating.

Alzheimer's disease (AD) is the most common neurodegenerative disorder characterized by the presence of extracellular plaques of β-amyloid peptides and intracellular tangles of hyperphosphorylated tau proteins in the brain. The vast majority of cases are late onset AD (LOAD), which are genetically heterogeneous and occur sporadically. High blood cholesterol is suggested to be a risk factor for this disease. Several neuropathological changes of LOAD can be reproduced by supplementing a rabbit's diet with 2% cholesterol for 12 weeks. Accumulating data in the literature suggest that microRNAs (miRNA) participate in the development of AD pathology. The present study focuses on the survey of changes of miRNA expression in rabbit brains during the progression of AD-like pathology using microarray followed by Taq-Man qRT-PCR analyses. Out of 1769 miRNA probes used in the experiments, 99 miRNAs were found to be present in rabbit brain, 57 were newly identified as miRNAs from rabbit brain. Eleven miRNAs showed significant changes over AD-like pathology progression. Among them, the changes of miR-125b, miR-98, miR-107, miR-30, along with 3 members of the let-7 family were similar to those observed in human AD samples, whereas the expression patterns of miR-15a, miR-26b, miR-9 and miR-576-3p were unique to this rabbit LOAD model. The significant up regulation of miR-26b is consistent with the decrease of leptin levels in the brains of cholesterol fed rabbit model for AD, confirming that miR-26b is indeed regulated by leptin and that both leptin and miR-26b may be involved in cholesterol induced AD-like pathology.