ABSTRACT
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 ( P < 0.05). The levels of ABCA1-labeled exosomal miR-135a increased in the CSF of MCI and DAT group compared to those of control group ( P < 0.05), slightly increased ( P > 0.05) in the serum of SCD patient group, and significantly increased in MCI and DAT patient groups compared to those of the control group ( P < 0.05). 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.
Subject(s)
ATP Binding Cassette Transporter 1 , Cognitive Dysfunction/blood , Exosomes , MicroRNAs/blood , ATP Binding Cassette Transporter 1/blood , ATP Binding Cassette Transporter 1/cerebrospinal fluid , Aged , Aged, 80 and over , Alzheimer Disease/blood , Alzheimer Disease/cerebrospinal fluid , Animals , Biomarkers/blood , Biomarkers/cerebrospinal fluid , Cell Line , Cognitive Dysfunction/cerebrospinal fluid , Erythrocytes/metabolism , Female , Humans , Leukocytes/metabolism , Male , Mice, Transgenic , Neurons/metabolismABSTRACT
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.
Subject(s)
Aged , Aged, 80 and over , Animals , Female , Humans , Male , ATP Binding Cassette Transporter 1/cerebrospinal fluid , Alzheimer Disease/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Cell Line , Cognitive Dysfunction/cerebrospinal fluid , Erythrocytes/metabolism , Exosomes , Leukocytes/metabolism , Mice, Transgenic , MicroRNAs/blood , Neurons/metabolismABSTRACT
BACKGROUND: Animal and human studies indicate that ABCA1-mediated cholesterol transport is important in Alzheimer's disease (AD). We hypothesized that the efficiency of cerebrospinal fluid (CSF) to facilitate ABCA1-mediated cholesterol efflux would be reduced in participants with mild cognitive impairment (MCI) or AD compared with cognitively healthy participants. METHODS AND RESULTS: CSF was collected from a cross-sectional study of cognitively healthy participants (n=47) and participants with MCI (n=35) or probable AD (n=26).The capacity of CSF to mediate cholesterol transport was assessed using a BHK cell line that can be induced to express the ABCA1 transporter. ABCA1-mediated cholesterol efflux capacity was 30% less in participants with MCI or AD compared with cognitively healthy participants (P<0.001 for both). Cholesterol efflux capacity correlated with CSF cholesterol content (r=0.37, P<0.001). CSF phosphatidylcholine decreased in participants with MCI and AD compared with cognitively healthy participants (9% less in MCI and 27% less in AD compared with cognitively healthy participants, P=0.01) and correlated with CSF efflux capacity (r=0.3, P=0.001). CSF sphingomyelin also correlated with the efflux capacity (r=0.24, P=0.02). Concentrations of CSF apoA-I and apoE did not significantly correlate with measures of efflux capacity. CONCLUSIONS: In people with MCI and AD, the capacity of CSF to facilitate ABCA1-mediated cholesterol efflux is impaired. This lesser cholesterol efflux in MCI supports a pathophysiological role for ABCA1-mediated cholesterol transport in early neurodegeneration.
