Whole-Blood Levels of MicroRNA-9 Are Decreased in Patients With Late-Onset Alzheimer Disease (original) (raw)

Profile of 6 microRNA in blood plasma distinguish early stage Alzheimer's disease patients from non-demented subjects

Oncotarget, 2017

Alzheimer's disease (AD) is the most common age-related dementia. Among its major challenges is identifying molecular signatures characteristic for the early AD stage in patients with Mild Cognitive Impairment (MCI-AD), which could serve for deciphering the AD pathomechanism and also as non-invasive, easy-to-access biomarkers. Using qRT-PCR we compared the microRNA (miRNA) profiles in blood plasma of 15 MCI-AD patients, whose diagnoses were confirmed by cerebrospinal fluid (CSF) biomarkers, with 20 AD patients and 15 non-demented, age-matched individuals (CTR).To minimize methodological variability, we adhered to standardization of blood and CSF assays recommended by the international Joint Programming for Neurodegenerative Diseases (JPND) BIOMARKAPD consortium, and we employed commercially available Exiqon qRT-PCR-assays. In the first screening, we assessed 179 miRNAs of plasma. We confirmed 23 miRNAs reported earlier as AD biomarker candidates in blood and found 26 novel diffe...

microRNA-150-5p: A Novel Blood-Based Biomarker for Alzheimer’s Dementia with Good Correlation to Cognition, Cerebrospinal Fluid Amyloid-β, and Cerebral Atrophy

2021

Background: There is an urgent need for non-invasive, cost-effective biomarkers for Alzheimer’s disease (AD), such as blood-based biomarkers. It is not only to support clinical diagnosis of dementia, but also to allow for timely pharmacological and non-pharmacological interventions evaluation. The aim of this study is to identify and validate a novel blood-based microRNA (miRNA) biomarker for dementia of Alzheimer’s disease type (DAT). The miRNA correlations with AD pathology and AD clinical-radiological imaging were conducted.Methods: We conducted miRNA-sequencing (miRNA-Seq) using peripheral blood mononuclear cells (PBMCs) isolated from a discovery cohort comprising DAT, mild cognitive impairment (MCI), and healthy subject (HS). Identified miRNA was validated in an independent cohort. Correlation analysis evaluated the relationships between miRNA expression and DAT clinical measures, including Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scores, CS...

Can Peripheral MicroRNA Expression Data Serve as Epigenomic (Upstream) Biomarkers of Alzheimer's Disease?

OMICS: A Journal of Integrative Biology, 2016

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common form of dementia. However, biomarkers that require testing in the brain tissue pose a formidable practical barrier to AD diagnostic innovation. MicroRNAs (miRNAs) are responsible for control of gene expression at the posttranscriptional level and are essential for the function of neuronal networks and neuronal survival. miRNA expression can impact the regulation of APP (amyloid beta A4 precursor protein), PSEN1 (presenilin 1), PSEN2 (presenilin 2), and BACE1 (beta-secretase 1) genes in the brain that were previously implicated in AD pathophysiology. Little is known, however, on the extent to which peripheral tissue (e.g., whole blood) miRNA variation might offer clinical predictive value for AD. Moreover, few studies have examined multiple peripheral miRNA expression data at the same time. We report here, to the best of our knowledge, the first whole-blood-based and parallel study of seven miRNAs (hsa-miR-9-5p, hsa-miR-29a-3p, hsa-miR-106a-5p, hsa-miR-106b-5p, hsa-miR-107, hsa-miR-125a-3p, and hsa-miR-125b-5p) in relation to AD susceptibility. Notably, these miRNAs are situated ''upstream'' to the genes implicated in AD. We measured the whole-blood miRNA expression by a real-time polymerase chain reaction in a large study sample (n = 281), comprising patients with AD (n = 172) and healthy controls (n = 109). A reduction in whole-blood expression of hsa-miR-9-5p, hsa-miR-106a-5p, hsa-miR-106b-5p, and hsa-miR-107 was significantly associated with an increased risk of AD (p < 0.05). Notably, after receiver operating characteristics curve analyses, hsa-miR-106a-5p displayed, as a predictor variable, 93% specificity and 68% sensitivity. On the other hand, the expression of hsa-miR-29a-3p, hsa-miR-125a-3p, and hsa-miR-125b-5p was not significantly different between patients and controls (p > 0.05). In conclusion, these observations warrant replication in larger samples while making a contribution to translational research, precision medicine, and biomarker literatures, by expanding the current efforts for AD diagnostic innovation to the realm of epigenomic pathways such as miRNA expression variation among patients.

Altered microRNAs related to synaptic function as potential plasma biomarkers for Alzheimer’s disease

Alzheimer's Research & Therapy, 2019

Background: Several evidences suggest that failure of synaptic function occurs at preclinical stages of Alzheimer's disease (AD) preceding neuronal loss and the classical AD pathological hallmarks. Nowadays, there is an urgent need to identify reliable biomarkers that could be obtained with non-invasive methods to improve AD diagnosis at early stages. Here, we have examined plasma levels of a group of miRNAs related to synaptic proteins in a cohort composed of cognitive healthy controls (HC), mild cognitive impairment (MCI) and AD subjects. Methods: Plasma and brain levels of miRNAs were analysed in two different cohorts including 38 HC, 26 MCI, 56 AD dementia patients and 27 frontotemporal dementia (FTD) patients. D'Agostino and Pearson and Shapiro-Wilk tests were used to evaluate data normality. miRNA levels between groups were compared using a two-sided nonparametric Mann-Whitney test and sensitivity and specificity was determined by receiver operating characteristic curve analysis. Results: Significant upregulation of miR-92a-3p, miR-181c-5p and miR-210-3p was found in the plasma of both MCI and AD subjects. MCI patients that progress to AD showed higher plasma levels of these miRNAs. By contrast, no changes in miR-92a-3p, miR-181c-5p or miR-210-3p levels were observed in plasma obtained from a cohort of FTD. Conclusion: Our study shows that plasma miR-92a-3p, miR-181c-5p and miR-210-3p constitute a specific molecular signature potentially useful as a potential biomarker for AD.

Increased microRNA-34c abundance in Alzheimer's disease circulating blood plasma

Frontiers in Molecular Neuroscience, 2014

Circulating microRNAs, present either in the cellular component, peripheral blood mononuclear cells (PBMC), or in cell-free plasma, have emerged as biomarkers for age-dependent systemic, disease-associated changes in many organs. Previously, we have shown that microRNA (miR)-34a is increased in circulating PBMC of Alzheimer's disease (AD) patients. In the present study, we show that this microRNA's sister, miR-34c, exhibits even greater increase in both cellular and plasma components of AD circulating blood samples, compared to normal age-matched controls. Statistical analysis shows the accuracy of levels of miR-34c assayed by receiver operating characteristic (ROC) analysis: the area under the curve is 0.99 (p < 0.0001) and the 95% confidence level extends from 0.97 to 1. Pearson correlation between miR-34c levels and mild and moderate AD, as defined by the mini-mental state examination (MMSE), shows an r-value of −0.7, suggesting a relatively strong inverse relationship between the two parameters. These data show that plasma levels of microRNA 34c are much more prominent in AD than those of its sister, miR-34a, or than its own level in PBMC. Transfection studies show that miR-34c, as does its sister miR-34a, represses the expression of several selected genes involved in cell survival and oxidative defense pathways, such as Bcl2, SIRT1, and others, in cultured cells. Taken together, our results indicate that increased levels of miR-34c in both PBMC and plasma may reflect changes in circulating blood samples in AD patients, compared to age-matched normal controls.

Blood serum miRNA: Non-invasive biomarkers for Alzheimer's disease

Experimental Neurology, 2012

There is an urgent need to identify non-invasive biomarkers for the detection of sporadic Alzheimer's disease (AD). We previously studied microRNAs (miRNAs) in AD autopsy brain samples and reported a connection between miR-137,-181c,-9,-29a/b and AD, through the regulation of ceramides. In this study, the potential role of these miRNAs as diagnostic markers for AD was investigated. We identified that these miRNAs were down-regulated in the blood serum of probable AD patients. The levels of these miRNAs were also reduced in the serum of AD risk factor models. Although the ability of these miRNAs to conclusively diagnose for AD is currently unknown, our findings suggest a potential use for circulating miRNAs, along with other markers, as non-invasive and relatively inexpensive biomarkers for the early diagnosis of AD, however, with further research and validation.

EXPRESSION OF SELECTED miRNAs IN CIRCULATING BLOOD OF EARLY AND LATE-ONSET ALZHEIMER DISEASE PATIENTS

İstanbul tıp fakültesi dergisi, 2021

Objective: Inflammation and associated microRNAs (miRNA) both play essential roles in the pathogenesis of Alzheimer's disease (AD). The expression profile of miRNA's in an AD brain, also reflected in the peripheral blood mononuclear cells, may give support to the inflammatory changes seen in the course of AD. We aimed to investigate the expression levels of specific inflammatory miRNAs (mir-146a, mir-144, mir-34a) in both blood leukocytes and plasma of AD patients and to evaluate their potential usability as biomarkers in AD diagnosis and to also demonstrate whether the expression of these miRNAs differ between early and late-onset AD patients. Methods: We investigated the expression levels of miRNAs in 16 early-onset and 26 late-onset AD patients and in their respective controls by using qRT-PCR. Results: Plasma mir-144 levels were significantly different between EOAD and LOAD patients (p=0.015). In addition, levels of leukocyte mir-34a were significantly down-regulated in EOAD compared to LOAD patients (p=0.027). Our results also showed significant positive correlations between age and plasma mir-144 and leukocyte mir-34a expressions.

MicroRNAs as Future Treatment Tools and Diagnostic Biomarkers in Alzheimer’s Disease

Alzheimer's Disease [Working Title], 2022

Alzheimer's disease (AD) is a neurodegenerative disorder and is considered to be the most common form of dementia. This disorder is characterized by the formation of amyloid β (Aβ) plaques, neurofibrillary tangles, and alterations in synaptic function, all of which cause memory loss and behavioral disturbances. Despite the high prevalence of AD, effective therapeutic and diagnostic tools remain unavailable. MicroRNAs (miRNAs, miRs) are regulatory non-coding RNAs that target mRNAs. MiRNAs are involved in the regulation of the expressions of APP and BACE1, Aβ clearance, and the formation of neuro-fibrillary tangles. Furthermore, there are evidences that show alteration in the expression of several miRs in AD. MicroRNA is emerging as a biomarker because they have high specificity and, efficiency, and can be detected in biological fluids such as cerebrospinal fluid, tear, urine, blood. Moreover, miRNAs may be acquired and measured easily by utilizing real-time PCR, next-generation sequencing, or microarray. These techniques are cost-effective in comparison with imaging techniques such as magnetic resonance imaging, positron emission tomography. These features make miRNAs viable therapeutic as well as diagnostic tools in the treatment of AD. This review covers the regulatory function of miRNAs in AD, as well as their prospective applications as diagnostic biomarkers.

Serum microRNA miR-501-3p as a potential biomarker related to the progression of Alzheimer's disease

Acta neuropathologica communications, 2017

MicroRNAs (miRNAs) are attractive molecules to utilize as one of the blood-based biomarkers for neurodegenerative disorders such as Alzheimer's disease (AD) because miRNAs are relatively stable in biofluid, including serum or plasma. To determine blood miRNA biomarkers for AD with next-generation sequencing genome-wide, we first surveyed 45 serum samples. These came from 27 AD patients and 18 controls (discovery set) that underwent autopsy within two weeks after their serum sampling and were neuropathologically diagnosed. We found that three miRNAs, hsa-miR-501-3p, hsa-let-7f-5p, and hsa-miR-26b-5p, were significantly deregulated between the AD samples and the controls. The deregulation for hsa-miR-501-3p was further confirmed by quantitative reverse transcription polymerase chain reaction (PCR) in a validation set composed of 36 clinically diagnosed AD patients and 22 age-matched cognitively normal controls with a sensitivity and specificity of 53% and 100%, respectively (area ...