scholarly journals Identifying Blood Transcriptome Biomarkers of Alzheimer’s Disease Using Transgenic Mice

2020 ◽  
Vol 57 (12) ◽  
pp. 4941-4951
Author(s):  
Shinichiro Ochi ◽  
Jun-ichi Iga ◽  
Yu Funahashi ◽  
Yuta Yoshino ◽  
Kiyohiro Yamazaki ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Transgenic Mice ◽  
Mrna Levels ◽  
Mouse Blood ◽  
Gene Transcripts ◽  
Functional Analyses ◽  
And Control ◽  
Apoe Mrna ◽  
Blood Transcriptome

Abstract The testing of pathological biomarkers of Alzheimer’s disease (AD), such as amyloid beta and tau, is time-consuming, expensive, and invasive. Here, we used 3xTg-AD mice to identify and validate putative novel blood transcriptome biomarkers of AD that can potentially be identified in the blood of patients. mRNA was extracted from the blood and hippocampus of 3xTg-AD and control mice at different ages and used for microarray analysis. Network and functional analyses revealed that the differentially expressed genes between AD and control mice modulated the immune and neuroinflammation systems. Five novel gene transcripts (Cdkn2a, Apobec3, Magi2, Parp3, and Cass4) showed significant increases with age, and their expression in the blood was collated with that in the hippocampus only in AD mice. We further assessed previously identified candidate biomarker genes. The expression of Trem1 and Trem2 in both the blood and brain was significantly increased with age. Decreased Tomm40 and increased Pink1 mRNA levels were observed in the mouse blood. The changes in the expression of Snca and Apoe mRNA in the mouse blood and brain were similar to those found in human AD blood. Our results demonstrated that the immune and neuroinflammatory system is involved in the pathophysiologies of aging and AD and that the blood transcriptome might be useful as a biomarker of AD.

MSR1 and NEP Are Correlated with Alzheimer’s Disease Amyloid Pathology and Apolipoprotein Alterations

2022 ◽  
pp. 1-13
Author(s):  
Justin Miron ◽  
Cynthia Picard ◽  
Anne Labonté ◽  
Daniel Auld ◽  
Judes Poirier ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Plasma Levels ◽  
Disease Stage ◽  
Mrna Levels ◽  
Strongly Correlated ◽  
Csf Levels ◽  
Barrier Breakdown ◽  
Highly Correlated ◽  
Apoe Mrna

Background: In mouse models of amyloidosis, macrophage receptor 1 (MSR1) and neprilysin (NEP) have been shown to interact to reduce amyloid burden in the brain. Objective: The purpose of this study is to analyze these two gene products in combination with apolipoproteins and Aβ 1 - 42 in the cerebrospinal fluid (CSF) and plasma of individuals at different stages of Alzheimer’s disease (AD), as well as in autopsied brain samples from ROSMAP (Religious Orders Study and Memory and Aging Project). Methods: CSF/plasma levels of MSR1 and NEP were measured using the sensitive primer extension assay technology. CSF Aβ 1 - 42 was assessed with ELISA, while CSF ApoE and ApoJ were measured with the Luminex’s multiplex technology. Brain MSR1, APOE, and CLU (ApoJ) mRNA levels were measured with RNA-Seq and contrasted to amyloid plaques pathology using CERAD staging. Results: While plasma and CSF MSR1 levels are significantly correlated, this correlation was not observed for NEP. In addition to be highly correlated to one another, CSF levels of both MSR1 and NEP are strongly correlated with AD status and CSF Aβ 1 - 42, ApoE, and ApoJ levels. In the cortical tissues of subjects from ROSMAP, MSR1 mRNA levels are correlated with CLU mRNA levels and the CERAD scores but not with APOE mRNA levels. Conclusion: The discrepancies observed between CSF/plasma levels of MSR1 and NEP with CSF Aβ 1 - 42 and ApoE concentrations can be explained by many factors, such as the disease stage or the involvement of the blood-brain barrier breakdown that leads to the infiltration of peripheral monocytes or macrophages.

scholarly journals Elevated mRNA-Levels of Gonadotropin-Releasing Hormone and Its Receptor in Plaque-Bearing Alzheimer's Disease Transgenic Mice

PLoS ONE ◽  
2014 ◽  
Vol 9 (8) ◽  
pp. e103607 ◽  
Author(s):  
Syed Nuruddin ◽  
Gry Helen Enger Syverstad ◽  
Sveinung Lillehaug ◽  
Trygve B. Leergaard ◽  
Lars N. G. Nilsson ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Transgenic Mice ◽  
Gonadotropin Releasing Hormone ◽  
Mrna Levels ◽  
Releasing Hormone

scholarly journals Neuroprotective Effects of Cistanches Herba Therapy on Patients with Moderate Alzheimer’s Disease

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Nan Li ◽  
Jianping Wang ◽  
Jun Ma ◽  
Zhiqiang Gu ◽  
Chao Jiang ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Independent Living ◽  
Control Group ◽  
Mrna Levels ◽  
Volume Changes ◽  
Neuroprotective Effects ◽  
Mri Scans ◽  
And Control ◽  
T Tau

Cistanches Herba (CH) is thought to be a “Yang-invigorating” material in traditional Chinese medicine. We evaluated neuroprotective effects of Cistanches Herba on Alzheimer’s disease (AD) patients. Moderate AD participants were divided into 3 groups: Cistanches Herba capsule (CH,n=10), Donepezil tablet (DON,n=8), and control group without treatmentn=6. We assessed efficacy by MMSE and ADAS-cog, and investigated the volume changes of hippocampus by 1.5 T MRI scans. Protein, mRNA levels, and secretions of total-tau (T-tau), tumor necrosis factor-α(TNF-α), and interleukin- (IL) 1β(IL-1β) in cerebrospinal fluid (CSF) were detected by Western blot, RT-PCR, and ELISA. The scores showed statistical difference after 48 weeks of treatment compared to control group. Meanwhile, volume changes of hippocampus were slight in drug treatment groups but distinct in control group; the levels of T-tau, TNF-α, and IL-1βwere decreased compared to those in control group. Cistanches Herba could improve cognitive and independent living ability of moderate AD patients, slow down volume changes of hippocampus, and reduce the levels of T-tau, TNF-α, and IL-1β. It suggested that Cistanches Herba had potential neuroprotective effects for moderate AD.

SPECIFIC PROPERTIES OF TUBULIN IN THE PREFRONTAL CORTEX IN CONTROL, SCHIZOPHRENIA AND VASCULAR DEMENTIA

2020 ◽  
pp. 65-71
Author(s):  
Burbaeva G.Sh. ◽  
Androsova L.V. ◽  
Vorobyeva E.A. ◽  
Savushkina O.K.
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Prefrontal Cortex ◽  
Vascular Dementia ◽  
Binding Activity ◽  
Nephelometric Method ◽  
Rate Of Polymerization ◽  
Mental Diseases ◽  
And Control ◽  
The Brain

The aim of the study was to evaluate the rate of polymerization of tubulin into microtubules and determine the level of colchicine binding (colchicine-binding activity of tubulin) in the prefrontal cortex in schizophrenia, vascular dementia (VD) and control. Colchicine-binding activity of tubulin was determined by Sherlinе in tubulin-enriched extracts of proteins from the samples. Measurement of light scattering during the polymerization of the tubulin was carried out using the nephelometric method at a wavelength of 450-550 nm. There was a significant decrease in colchicine-binding activity and the rate of tubulin polymerization in the prefrontal cortex in both diseases, and in VD to a greater extent than in schizophrenia. The obtained results suggest that not only in Alzheimer's disease, but also in other mental diseases such as schizophrenia and VD, there is a decrease in the level of tubulin in the prefrontal cortex of the brain, although to a lesser extent than in Alzheimer's disease, and consequently the amount of microtubules.

Synthesis of a Novel Curcumin Derivative as a Potential Imaging Probe in Alzheimer’s Disease Imaging

2019 ◽  
Vol 16 (8) ◽  
pp. 723-731 ◽  
Author(s):  
Alexander Sturzu ◽  
Sumbla Sheikh ◽  
Hubert Kalbacher ◽  
Thomas Nägele ◽  
Christopher Weidenmaier ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Flow Cytometry ◽  
Transgenic Mice ◽  
Ex Vivo ◽  
Amyloid Plaques ◽  
Laser Scanning Microscopy ◽  
Β Amyloid ◽  
Curcumin Derivative

Background: Curcumin has been of interest in the field of Alzheimer’s disease. Early studies on transgenic mice showed promising results in the reduction of amyloid plaques.However, curcumin is very poorly soluble in aqueous solutions and not easily accessible to coupling as it contains only phenolic groups as potential coupling sites. For these reasons only few imaging studies using curcumin bound as an ester were performed and curcumin is mainly used as nutritional supplement. Methods: In the present study we produced an aminoethyl ether derivative of curcumin using a nucleophilic substitution reaction. This is a small modification and should not impact the properties of curcumin while introducing an easily accessible reactive amino group. This novel compound could be used to couple curcumin to other molecules using the standard methods of peptide synthesis. We studied the aminoethyl-curcumin compound and a tripeptide carrying this aminoethyl-curcumin and the fluorescent dye fluorescein (FITC-curcumin) in vitro on cell culture using confocal laser scanning microscopy and flow cytometry. Then these two substances were tested ex vivo on brain sections prepared from transgenic mice depicting Alzheimer-like β-amyloid plaques. Results: In the in vitro CLSM microscopy and flow cytometry experiments we found dot-like unspecific uptake and only slight cytotoxicity correlating with this uptake. As these measurements were optimized for the use of fluorescein as dye we found that the curcumin at 488nm fluorescence excitation was not strong enough to use it as a fluorescence marker in these applications. In the ex vivo sections CLSM experiments both the aminoethyl-curcumin and the FITC-curcumin peptide bound specifically to β- amyloid plaques. Conclusion: In conclusion we successfully produced a novel curcumin derivative which could easily be coupled to other imaging or therapeutic molecules as a sensor for amyloid plaques.

MiR-335-5p Inhibits β-Amyloid (Aβ) Accumulation to Attenuate Cognitive Deficits Through Targeting c-jun-N-terminal Kinase 3 in Alzheimer’s Disease

2020 ◽  
Vol 17 (1) ◽  
pp. 93-101 ◽  
Author(s):  
Dan Wang ◽  
Zhifu Fei ◽  
Song Luo ◽  
Hai Wang
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Transgenic Mice ◽  
Western Blot ◽  
Mrna Expression ◽  
Cognitive Deficits ◽  
Protein Levels ◽  
Amyloid Aβ ◽  
Β Amyloid ◽  
The Relationship

Objectives: Alzheimer's disease (AD), also known as senile dementia, is a common neurodegenerative disease characterized by progressive cognitive impairment and personality changes. Numerous evidences have suggested that microRNAs (miRNAs) are involved in the pathogenesis and development of AD. However, the exact role of miR-335-5p in the progression of AD is still not clearly clarified. Methods: The protein and mRNA levels were measured by western blot and RNA extraction and quantitative real-time PCR (qRT-PCR), respectively. The relationship between miR-335-5p and c-jun-N-terminal kinase 3 (JNK3) was confirmed by dual-luciferase reporter assay. SH-SY5Y cells were transfected with APP mutant gene to establish the in vitro AD cell model. Flow cytometry and western blot were performed to evaluate cell apoptosis. The APP/PS1 transgenic mice were used as an in vivo AD model. Morris water maze test was performed to assess the effect of miR- 335-5p on the cognitive deficits in APP/PS1 transgenic mice. Results: The JNK3 mRNA expression and protein levels of JNK3 and β-Amyloid (Aβ) were significantly up-regulated, and the mRNA expression of miR-335-5p was down-regulated in the brain tissues of AD patients. The expression levels of miR-335-5p and JNK3 were significantly inversely correlated. Further, the dual Luciferase assay verified the relationship between miR-335- 5p and JNK3. Overexpression of miR-335-5p significantly decreased the protein levels of JNK3 and Aβ and inhibited apoptosis in SH-SY5Y/APPswe cells, whereas the inhibition of miR-335-5p obtained the opposite results. Moreover, the overexpression of miR-335-5p remarkably improved the cognitive abilities of APP/PS1 mice. Conclusion: The results revealed that the increased JNK3 expression, negatively regulated by miR-335-5p, may be a potential mechanism that contributes to Aβ accumulation and AD progression, indicating a novel approach for AD treatment.

scholarly journals Distinct network topology in Alzheimer’s disease and behavioral variant frontotemporal dementia

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Adeline Su Lyn Ng ◽  
Juan Wang ◽  
Kwun Kei Ng ◽  
Joanna Su Xian Chong ◽  
Xing Qian ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Frontotemporal Dementia ◽  
Network Topology ◽  
Neuropsychiatric Symptoms ◽  
Brain Network ◽  
Salience Network ◽  
Behavioral Variant Frontotemporal Dementia ◽  
Control Networks ◽  
And Control

Abstract Background Alzheimer’s disease (AD) and behavioral variant frontotemporal dementia (bvFTD) cause distinct atrophy and functional disruptions within two major intrinsic brain networks, namely the default network and the salience network, respectively. It remains unclear if inter-network relationships and whole-brain network topology are also altered and underpin cognitive and social–emotional functional deficits. Methods In total, 111 participants (50 AD, 14 bvFTD, and 47 age- and gender-matched healthy controls) underwent resting-state functional magnetic resonance imaging (fMRI) and neuropsychological assessments. Functional connectivity was derived among 144 brain regions of interest. Graph theoretical analysis was applied to characterize network integration, segregation, and module distinctiveness (degree centrality, nodal efficiency, within-module degree, and participation coefficient) in AD, bvFTD, and healthy participants. Group differences in graph theoretical measures and empirically derived network community structures, as well as the associations between these indices and cognitive performance and neuropsychiatric symptoms, were subject to general linear models, with age, gender, education, motion, and scanner type controlled. Results Our results suggested that AD had lower integration in the default and control networks, while bvFTD exhibited disrupted integration in the salience network. Interestingly, AD and bvFTD had the highest and lowest degree of integration in the thalamus, respectively. Such divergence in topological aberration was recapitulated in network segregation and module distinctiveness loss, with AD showing poorer modular structure between the default and control networks, and bvFTD having more fragmented modules in the salience network and subcortical regions. Importantly, aberrations in network topology were related to worse attention deficits and greater severity in neuropsychiatric symptoms across syndromes. Conclusions Our findings underscore the reciprocal relationships between the default, control, and salience networks that may account for the cognitive decline and neuropsychiatric symptoms in dementia.

scholarly journals Role of the lncRNA BACE1-AS in shared disease mechanisms between heart failure and Alzheimer's disease

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Greco ◽  
A Made' ◽  
A.S Tascini ◽  
J Garcia Manteiga ◽  
S Castelvecchio ◽  
...  
Keyword(s):  
Heart Failure ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
In Situ Hybridization ◽  
Cell Apoptosis ◽  
Common Disease ◽  
Funding Source ◽  
Mrna Levels ◽  
Rna Seq

Abstract Background BACE1 encodes for β-secretase, the key enzyme involved in β-amyloid (βA) generation, a peptide well known for its involvement in Alzheimer's disease (AD). Of note, heart failure (HF) and AD share several risk factors and effectors. We recently showed that, in the heart of ischemic HF patients, the levels of both BACE1, its antisense RNA BACE1-AS and βA are all increased. BACE1-AS positively regulates the expression of BACE1, triggering βA intracellular accumulation, and its overexpression or βA administration induce cardiovascular-cell apoptosis. Aim To characterize the transcripts of the BACE1 locus and to investigate the molecular mechanisms underpinning BACE1-AS regulation of cell vitality. Methods By PCR and sequencing, we studied in the heart the expression of a variety of antisense BACE1 transcripts predicted by FANTOM CAT Epigenome. We studied BACE1 RNA stability by BrdU pulse chase experiments (BRIC assay). The cellular localization of BACE1-AS RNA was investigated by in situ hybridization assay. BACE1-AS binding RNAs were evaluated by BACE1-AS-MS2-Tag pull-down in AC16 cardiomyocytes followed by RNA-seq. Enriched RNAs were validated by qPCR and analysed by bioinformatics comparison with publicly available gene expression datasets of AD brains. Results We readily detected several antisense BACE1 transcripts expressed in AC16 cardiomyocytes; however, only BACE1-AS RNAs overlapping exon 6 of BACE1 positively regulated BACE1 mRNA levels, acting by increasing its stability. BACE1 silencing reverted cell apoptosis induced by BACE1-AS expression, indicating that BACE1 is a functional target of BACE1-AS. However, in situ hybridization experiments indicated a mainly nuclear localization for BACE1-AS, which displayed a punctuated distribution, compatible with chromatin association and indicative of potential additional targets. To identify other BACE1-AS binding RNAs, a BACE1-AS-MS2-tag pull-down was performed and RNA-seq of the enriched RNAs identified 698 BACE1-AS interacting RNAs in cardiomyocytes. Gene ontology of the BACE1-AS binding RNAs identified categories of relevance for cardiovascular or neurological diseases, such as dopaminergic synapse, glutamatergic synapse, calcium signalling pathway and voltage-gated channel activity. In spite of the differences between brain and heart transcriptomes, BACE1-AS-interacting RNAs identified in cardiomyocytes were significantly enriched in transcripts differentially expressed in AD brains as well as in RNAs expressed by enhancer genomic regions that are significantly hypomethylated in AD brains. Conclusions These data shed a new light on the complexity of BACE1-AS locus and on the existence of RNAs interacting with BACE1-AS with a potential as enhancer-RNAs. Moreover, the dysregulation of the BACE1-AS/BACE1/βA pathway may be a common disease mechanism shared by cardiovascular and neurological degenerative diseases. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Italian Health Ministery_Ricerca Corrente 2020

scholarly journals Alterations in the Gut-Microbial-Inflammasome-Brain Axis in a Mouse Model of Alzheimer’s Disease

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 779
Author(s):  
Pradeep K. Shukla ◽  
David F. Delotterie ◽  
Jianfeng Xiao ◽  
Joseph F. Pierre ◽  
RadhaKrishna Rao ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Mouse Model ◽  
Gut Microbiota ◽  
Transgenic Mice ◽  
Nlrp3 Inflammasome ◽  
Inflammasome Activation ◽  
Gut Barrier Function ◽  
Elevated Expression ◽  
5Xfad Mice

Alzheimer’s disease (AD), a progressive neurodegenerative disorder characterized by memory loss and cognitive decline, is a major cause of death and disability among the older population. Despite decades of scientific research, the underlying etiological triggers are unknown. Recent studies suggested that gut microbiota can influence AD progression; however, potential mechanisms linking the gut microbiota with AD pathogenesis remain obscure. In the present study, we provided a potential mechanistic link between dysbiotic gut microbiota and neuroinflammation associated with AD progression. Using a mouse model of AD, we discovered that unfavorable gut microbiota are correlated with abnormally elevated expression of gut NLRP3 and lead to peripheral inflammasome activation, which in turn exacerbates AD-associated neuroinflammation. To this end, we observe significantly altered gut microbiota compositions in young and old 5xFAD mice compared to age-matched non-transgenic mice. Moreover, 5xFAD mice demonstrated compromised gut barrier function as evident from the loss of tight junction and adherens junction proteins compared to non-transgenic mice. Concurrently, we observed increased expression of NLRP3 inflammasome and IL-1β production in the 5xFAD gut. Consistent with our hypothesis, increased gut–microbial–inflammasome activation is positively correlated with enhanced astrogliosis and microglial activation, along with higher expression of NLRP3 inflammasome and IL-1β production in the brains of 5xFAD mice. These data indicate that the elevated expression of gut–microbial–inflammasome components may be an important trigger for subsequent downstream activation of inflammatory and potentially cytotoxic mediators, and gastrointestinal NLRP3 may promote NLRP3 inflammasome-mediated neuroinflammation. Thus, modulation of the gut microbiota may be a potential strategy for the treatment of AD-related neurological disorders in genetically susceptible hosts.

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