Objective: In the present study, the ABCA1 was used as a label to capture specific exosomes, the level of ABCA1-labeled exosomal microRNA-135a (miR-135a) was evaluated for the diagnosis of Alzheimer's disease (AD), especially in patients with early stages of AD. Methods: This is a preliminary research focused on the levels of ABCA1 in WBCs, RBCs, HT-22 cells, and neuron cells. The diagnostic value of ABCA1-labeled exosomal miR-135a was examined using the CSF and serum of APP/PS1 double transgenic mice, and 152 patients with SCD, 131 patients with MCI, 198 patients with DAT, and 30 control subjects. Results: The level of ABCA1 exosomes harvested from HT-22 cells and neuron culture medium was significantly higher compared to that of RBCs and WBCs ( Conclusion This study outlines a method to capture specific exosomes and detect them using immunological methods, which is more efficient for early diagnosis of AD.
ATP Binding Cassette Transporter 1/cerebrospinal fluid* ; Aged ; Aged, 80 and over ; Alzheimer Disease/cerebrospinal fluid* ; Animals ; Biomarkers/cerebrospinal fluid* ; Cell Line ; Cognitive Dysfunction/cerebrospinal fluid* ; Erythrocytes/metabolism* ; Exosomes ; Female ; Humans ; Leukocytes/metabolism* ; Male ; Mice, Transgenic ; MicroRNAs/blood* ; Neurons/metabolism*

Suvorexant, an orexin receptor antagonist used for insomnia, has been shown to have a preventive effect on delirium in a randomized placebo-controlled trial. However, its effectiveness in the management of nocturnal delirium has not yet been determined. Here we report four cases in which elderly patients with moderate to severe Alzheimer's disease who developed nocturnal delirium were treated with suvorexant. In case 1, 15 mg suvorexant was initiated to manage nocturnal delirium refractory to antipsychotics, antidepressants, and a Japanese herbal medicine, resulting in immediate sleep improvement. However, treatment discontinuation led to recurrence of symptoms, which were reversed by recommencing suvorexant. In case 2, as antipsychotics used for the treatment of nocturnal delirium were ineffective, 15 mg suvorexant was administered. The patient achieved rapid improvement in sleep. In case 3, the use of atypical antipsychotics for the treatment of nocturnal delirium was contraindicated, as the patient had diabetes. Therefore, 15 mg suvorexant was administered following good outcomes in cases 1 and 2, resulting in immediate sleep improvement. Finally, in case 4, 15 mg suvorexant was used as an initial medication for nocturnal delirium, and the patient showed sleep improvement immediately. Elevated orexin levels in the cerebrospinal fluid are reportedly linked to sleep deterioration in patients with moderate to severe Alzheimer's disease. The immediate and reproducible action and effectiveness of suvorexant observed in our patients suggest that enhanced cerebral orexin activity might be associated with sleep-wake cycle disturbances due to delirium in elderly patients with Alzheimer's disease.
Aged ; Alzheimer Disease ; Antidepressive Agents ; Antipsychotic Agents ; Asian Continental Ancestry Group ; Cerebrospinal Fluid ; Delirium ; Herbal Medicine ; Humans ; Orexins ; Recurrence ; Sleep Initiation and Maintenance Disorders

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD) could be misleading in idiopathic normal-pressure hydrocephalus (iNPH). We therefore investigated the CSF biomarkers in 18F-florbetaben amyloid-negative positron-emission tomography (PET) [amyloid PET(−)] iNPH, amyloid-positive PET [amyloid PET(+)] AD, and cognitively normal (CN) subjects. METHODS: Ten amyloid PET(+) AD patients (56.7±5.6 years old, mean±standard deviation), 10 amyloid PET(−) iNPH patients (72.8±4.5 years old), and 8 CN subjects (61.2±6.5 years old) were included. We measured the levels of β-amyloid (Aβ)40, Aβ42, total tau (t-tau) protein, and phosphorylated tau (p-tau) protein in the CSF using enzyme-linked immunosorbent assays. RESULTS: The level of Aβ42 and the Aβ42/Aβ40 ratio in the CSF were significantly lower in AD than in iNPH or CN subjects. The Aβ40 level did not differ significantly between AD and iNPH (p=1.000), but it did between AD and CN subjects (p=0.032). The levels of both t-tau and p-tau were higher in AD than in iNPH or CN subjects. The levels of Aβ42, Aβ40, t-tau, and p-tau were lower in iNPH than in CN subjects, but there was no significant difference after controlling for age. CONCLUSIONS: Our results suggest that the mechanism underlying low CSF Aβ levels differs between amyloid PET(−) iNPH and amyloid PET(+) AD subjects. The lower levels of all CSF biomarkers in iNPH patients might be due to reduced clearances from extracellular fluid and decreased brain metabolism of the periventricular zone in iNPH resulting from glymphatic dysfunction.
Alzheimer Disease ; Amyloid ; Biomarkers ; Brain ; Cerebrospinal Fluid ; Enzyme-Linked Immunosorbent Assay ; Extracellular Fluid ; Humans ; Hydrocephalus ; Metabolism ; Positron-Emission Tomography

BACKGROUND: Normal pressure hydrocephalus (NPH) is an etiology of dementia that is reversible following cerebrospinal fluid shunt placement, however, surgical intervention not always clinically effective and the respons to shunt therapy is poorly understood. Furthermore, NPH is a source of comorbidity in diseases with neurodegenerative pathology, such as Alzheimer's disease (AD). CASE REPORT: A 61-year-old woman presented to the neurology clinic with progressive gait difficulties and cognitive impairment over five years. Nine years after ventriculoperitoneal (VP) shunt treatment, the patient began to experience frequent falls. There was no improvement in clinical symptoms after the alteration of valve pressure on the VP shunt. An 18F-florbetaben amyloid positron emission tomography scan showed increased diffusion uptake over the bilateral cortices, precuneus, and posterior cingulate cortex. CONCLUSIONS: The patient of NPH was unresponsive to shunt therapy due to the development of AD.
Accidental Falls ; Alzheimer Disease* ; Amyloid ; Cerebrospinal Fluid Shunts ; Cognition Disorders ; Comorbidity ; Dementia ; Diffusion ; Female ; Gait ; Gyrus Cinguli ; Humans ; Hydrocephalus* ; Hydrocephalus, Normal Pressure ; Middle Aged ; Neurology ; Parietal Lobe ; Pathology ; Positron-Emission Tomography

BACKGROUND AND PURPOSE: The cerebrospinal fluid (CSF) biomarkers play an important supportive role as diagnostic and predictive indicators of Alzheimer's disease (AD). About 30% of controls in old age show abnormal values of CSF biomarkers and display a higher risk for AD compared with those showing normal values. The cut-off values are determined by their diagnostic accuracy. However, the current cut-off values may be less accurate, because controls include high-risk groups of AD. We sought to develop models of patients with AD, who are homogenous for CSF biomarkers. METHODS: We included participants who had CSF biomarker data in the Alzheimer's Disease Neuroimaging Initiative database. We investigated the factors related to CSF biomarkers in patients with AD using linear mixed models. Using the factors, we developed models corresponding to CSF biomarkers to classify patients with mild cognitive impairment (MCI) into high risk and low risk and analyzed the conversion from MCI to AD using the Cox proportional hazards model. RESULTS: APOE ε4 status and age were significantly related to CSF Aβ1-42. CSF t-tau, APOE ε2 status and sex were significant factors. The CSF p-tau181 was associated with age and frequency of diagnosis. Accordingly, we modeled the three CSF biomarkers of AD. In MCI without APOE ε4, our models were better predictors of conversion. CONCLUSIONS: We can interpret CSF biomarkers based on the models derived from the data obtained from patients with AD.
Alzheimer Disease* ; Apolipoproteins E ; Biomarkers ; Cerebrospinal Fluid ; Diagnosis ; Humans ; Methods* ; Mild Cognitive Impairment* ; Neuroimaging ; Proportional Hazards Models ; Reference Values

BACKGROUND AND PURPOSE: Alzheimer's disease (AD) is characterized by the accumulation of amyloid-β proteins (Aβ). In this study we explored the correlation of plasma Aβ40 and Aβ42 concentrations with Aβ42, total tau (tTau) and phosphorylated tau 181 (pTau181) levels in cerebrospinal fluid (CSF) in AD and control subjects to further understand the characteristics of plasma Aβ proteins levels. METHODS: The consecutive subjects (44 AD and 47 controls) in this study were recruited. The plasma levels of Aβ40 and Aβ42 were measured using a commercially available sandwich enzyme-linked immunosorbent assay (ELISA) kits. And the corresponding CSFs were analyzed in terms of Aβ42, tTau and pTau181 concentrations using INNOTEST ELISA kits. Further, the albumin levels were measured both in serum and CSF and albumin ratio was obtained to check the integrity of blood-brain barrier. RESULTS: CSF Aβ42 concentrations were significantly decreased while tTau and pTau181 levels were significantly increased in AD subjects. The plasma levels of Aβ42 were significantly lower (p=0.007), while the Aβ40/Aβ42 ratio was significantly higher (p<0.001) in AD patients than in controls. The overall plasma Aβ42 levels showed a positive correlation with those of CSF Aβ42 (p=0.001), but not with the others in CSF. In subgroup analysis, the CSF Aβ42 demonstrated positive correlation with not only plasma Aβ42 but also Aβ40 levels in controls. However, no significant relationship was noted between plasma and CSF Aβ proteins in AD group. CONCLUSIONS: The plasma Aβ42 and Aβ40 concentrations were shown to have a close relationship with CSF Aβ42 levels in controls, but not in AD subjects. Our results suggest that the correlation between plasma Aβ40 and CSF Aβ42 levels is perturbed in AD.
Alzheimer Disease* ; Biomarkers* ; Blood-Brain Barrier ; Cerebrospinal Fluid* ; Enzyme-Linked Immunosorbent Assay ; Humans ; Plasma* ; Statistics as Topic*

No disease-modifying therapies (DMT) for neurodegenerative diseases (NDs) have been established, particularly for Alzheimer's disease (AD) and Parkinson's disease (PD). It is unclear why candidate drugs that successfully demonstrate therapeutic effects in animal models fail to show disease-modifying effects in clinical trials. To overcome this hurdle, patients with homogeneous pathologies should be detected as early as possible. The early detection of AD patients using sufficiently tested biomarkers could demonstrate the potential usefulness of combining biomarkers with clinical measures as a diagnostic tool. Cerebrospinal fluid (CSF) biomarkers for NDs are being incorporated in clinical trials designed with the aim of detecting patients earlier, evaluating target engagement, collecting homogeneous patients, facilitating prevention trials, and testing the potential of surrogate markers relative to clinical measures. In this review we summarize the latest information on CSF biomarkers in NDs, particularly AD and PD, and their use in clinical trials. The large number of issues related to CSF biomarker measurements and applications has resulted in relatively few clinical trials on CSF biomarkers being conducted. However, the available CSF biomarker data obtained in clinical trials support the advantages of incorporating CSF biomarkers in clinical trials, even though the data have mostly been obtained in AD trials. We describe the current issues with and ongoing efforts for the use of CSF biomarkers in clinical trials and the plans to harness CSF biomarkers for the development of DMT and clinical routines. This effort requires nationwide, global, and multidisciplinary efforts in academia, industry, and regulatory agencies to facilitate a new era.
Alzheimer Disease ; Biomarkers* ; Cerebrospinal Fluid* ; Humans ; Models, Animal ; Neurodegenerative Diseases ; Parkinson Disease ; Pathology ; Therapeutic Uses

BACKGROUND: The described clinical characteristics of early-onset Alzheimer's disease (EOAD) are distinct from that of late-onset AD. We reported a patient with atypical EOAD. CASE REPORT: A 54-year-old, truck driver developed gradual visuospatial, language and calculation deficits for 3 months. The neuropsychological impairments were extensive. Brain MRI revealed asymmetric atrophy in left medial temporal lobe along with distinct widening of sylvian fissure. (18)F-florbetapir-positron emission tomography (PET) showed a high uptake in the cortex. Further, the profiles of cerebrospinal fluid (CSF) biomarker were compatible with AD. CONCLUSIONS: We diagnosed the patient as EOAD based on the result of biomarker study. Increased Abeta burden was identified through amyloid PET imaging and decreased CSF Abeta level. The high rise of CSF Tau proteins was in agreement with the patient's extensive and rapid cognitive decline. This case report demonstrates the importance of AD biomarker study in confronting early-onset dementia with atypical clinical presentation.
Alzheimer Disease* ; Amyloid ; Atrophy ; Brain ; Cerebrospinal Fluid ; Dementia* ; Humans ; Magnetic Resonance Imaging ; Middle Aged ; Motor Vehicles ; Positron-Emission Tomography ; tau Proteins ; Temporal Lobe

Cerebrospinal fluid (CSF) can provide vital informative about pathological processes occurring in the brain. In particular, the CSF concentrations of Abeta42, tTau, and pTau181 are useful for the early diagnosis of Alzheimer's disease (AD). However, many studies have demonstrated that confounding factors related to the preanalytical processing of CSF can seriously influence measurements of these AD biomarkers. It is therefore important to develop a standardized protocol for the acquisition and handling of CSF, particularly with regard to the types of tube used for collection and storage, the proper aliquot volume, blood contamination, and the number of tube transfers and freeze-thaw cycles, because these aspects of the procedure have been shown to affect AD biomarker measurements. A survey of the impact of several individual preanalytical procedures on the measurement of AD biomarkers in CSF was conducted for this review article, and the implications of the differences among them are discussed. Furthermore, following a review of the procedures used in Korean and international biomarker laboratories, a consensus was reached among a cooperative Korean multicenter research group regarding a standardized protocol for the analysis of AD biomarkers in CSF. All efforts were made to be stringent regarding the controversial issues associated with this protocol, thus minimizing the confounding influence of various factors on current investigations using established AD biomarkers and on future studies using novel biomarkers of AD and other neurodegenerative disorders.
Alzheimer Disease* ; Biomarkers* ; Blood Volume ; Brain ; Cerebrospinal Fluid* ; Consensus* ; Early Diagnosis ; Korea ; Neurodegenerative Diseases ; Pathologic Processes

Cerebral amyloid angiopathy (CAA) involves cerebrovascular amyloid deposition and is classified into several types according to the amyloid protein involved. Of these, sporadic amyloid beta-protein (Abeta)-type CAA is most commonly found in older individuals and in patients with Alzheimer's disease (AD). Cerebrovascular Abeta deposits accompany functional and pathological changes in cerebral blood vessels (CAA-associated vasculopathies). CAA-associated vasculopathies lead to development of hemorrhagic lesions [lobar intracerebral macrohemorrhage, cortical microhemorrhage, and cortical superficial siderosis (cSS)/focal convexity subarachnoid hemorrhage (SAH)], ischemic lesions (cortical infarction and ischemic changes of the white matter), and encephalopathies that include subacute leukoencephalopathy caused by CAA-associated inflammation/angiitis. Thus, CAA is related to dementia, stroke, and encephalopathies. Recent advances in diagnostic procedures, particularly neuroimaging, have enabled us to establish a clinical diagnosis of CAA without brain biopsies. Sensitive magnetic resonance imaging (MRI) methods, such as gradient-echo T2* imaging and susceptibility-weighted imaging, are useful for detecting cortical microhemorrhages and cSS. Amyloid imaging with amyloid-binding positron emission tomography (PET) ligands, such as Pittsburgh Compound B, can detect CAA, although they cannot discriminate vascular from parenchymal amyloid deposits. In addition, cerebrospinal fluid markers may be useful, including levels of Abeta40 for CAA and anti-Abeta antibody for CAA-related inflammation. Moreover, cSS is closely associated with transient focal neurological episodes (TFNE). CAA-related inflammation/angiitis shares pathophysiology with amyloid-related imaging abnormalities (ARIA) induced by Abeta immunotherapies in AD patients. This article reviews CAA and CAA-related disorders with respect to their epidemiology, pathology, pathophysiology, clinical features, biomarkers, diagnosis, treatment, risk factors, and future perspectives.
Alzheimer Disease ; Amyloid ; Amyloid beta-Peptides ; Biomarkers ; Biopsy ; Blood Vessels ; Brain ; Cerebral Amyloid Angiopathy* ; Cerebrospinal Fluid ; Cerebrovascular Disorders ; Dementia ; Diagnosis ; Epidemiology ; Humans ; Immunotherapy ; Infarction ; Inflammation ; Leukoencephalopathies ; Ligands ; Magnetic Resonance Imaging ; Neuroimaging ; Pathology ; Plaque, Amyloid ; Positron-Emission Tomography ; Risk Factors ; Siderosis ; Stroke ; Subarachnoid Hemorrhage