Small RNA Sequencing of Sporadic Amyotrophic Lateral Sclerosis Cerebrospinal Fluid Reveals Differentially Expressed miRNAs Related to Neural and Glial Activity
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ABSTRACT: Amyotrophic lateral sclerosis (ALS) is a clinical subtype of motor neurone disease (MND), a fatal neurodegenerative disease involving the loss of both the upper and lower motor neurones from the motor cortex, brainstem, and spinal cord. Identifying specific disease biomarkers would help to not only improve diagnostic delay but also to classify disease subtypes, monitor response to therapeutic drugs and track disease progression. miRNAs are small non-coding RNA responsible for regulating gene expression and ultimately protein expression and have been used as biomarkers for many cancers and neurodegenerative disorders. Investigating the detection of miRNAs in cerebrospinal fluid (CSF), the fluid that bathes the central nervous system (CNS) is a prime target for identifying potential biomarkers for ALS. This is the first study to investigate the expression of miRNAs in the CSF of ALS patients using small RNA sequencing. We detected differentially expressed miRNAs in the CSF of sporadic ALS (sALS) patients related to neural and glial activity. Additionally, miRNAs involved in glucose metabolism and the regulation of oxidative stress were also identified. Detecting the presence of potential CSF derived miRNA biomarkers in sALS could open up a whole new area of knowledge to help gain a better understanding of disease pathophysiology.
Project description:Amyotrophic lateral sclerosis (ALS) is an incurable and fatal neurodegenerative disease. Increasing the chances of success for future clinical strategies requires more in-depth knowledge of the molecular basis underlying disease heterogeneity. We recently laid the foundation for a molecular taxonomy of ALS by whole transcriptome expression profiling of motor cortex from sporadic ALS (SALS) patients. Here, we analyzed genomic structural aberrations occurring in the same patients, by using a customized exon-centered comparative genomic hybridization array (aCGH) covering a large panel of ALS-related genes. Integrative analysis of copy number profiles with their associated transcriptomic data revealed subtype-specific genomic perturbations and candidate driver genes positively correlated with transcriptional signatures, which might represent novel potential biomarkers and therapeutic targets. This study represents the first comprehensive “omics” analysis of molecular events characterizing SALS pathology, providing a road map to facilitate genome-guided personalized diagnosis and treatments for this devastating disease.
Project description:Amyotrophic lateral sclerosis (ALS) is progressive neurodegenerative diseases characterized by the relentless loss of upper and lower motor neurons, eventually leading to death. Critical to the mission of developing effective therapies for ALS is the discovery of biomarkers that can illuminate mechanisms of neurodegeneration, as well as that, can be used for diagnostic, prognostic, or pharmacodynamic value across the disease. Here, we merged unbiased discovery-based approaches and targeted quantitative comparative analyses to identify proteins that are altered in cerebrospinal fluid (CSF) from ALS. Mass spectrometry (MS)-based proteomic approaches employing tandem mass tags (TMT) quantification methods from 40 CSF samples comprising 20 patients with ALS and 20 healthy control (HC) individuals identified 53 candidate biomarker proteins after CSF fractionation. Notably, these candidate biomarkers included both previously identified proteins validating our approach and novel ones, expanding the applicability of the biomarkers. Candidate biomarkers were subsequently examined using parallel reaction monitoring (PRM) MS methods on 61 unfractionated CSF samples comprising 30 patients with ALS and 31 HC individuals. Fifteen candidate biomarkers (APOB, APP, CAMK2A, CHI3L1, CHIT1, CLSTN3, ERAP2, FSTL4, GPNMB, JCHAIN, L1CAM, NPTX2, SERPINA1, SERPINA3 and UCHL1) showed significant differences between ALS and Control. Taken together, this study identifies multiple novel proteins that are altered in ALS, which provides the foundation for developing biomarkers for ALS.
Project description:Extracellular vesicles (EVs) hold the potential for elucidating the pathogenesis and serving as biomarkers of amyotrophic lateral sclerosis (ALS). Notably, the comparative and longitudinal alterations in the protein profiles of EVs in serum (sEVs) and CSF (cEVs) of sporadic ALS (SALS) patients remain unexplored. This study sought to reveal such changes by collecting serum and CSF at fixed intervals from 10 controls and 20 SALS patients participating in the Ropinirole Hydrochloride Remedy for Amyotrophic Lateral Sclerosis trial. We also aimed to reveal longitudinal changes with disease progression and the effects of ropinirole hydrochloride (ROPI, a dopamine D2 receptor agonist identified as an anti-ALS drug candidate using induced pluripotent stem cell drug discovery) on protein profiles of EVs. Comprehensive proteomic analyses of EVs extracted from these samples were conducted using liquid chromatography-mass spectrometry to trace longitudinal shifts linked to disease progression and the influence of ROPI on EV protein profiles. The findings revealed notable disparities but high congruity in sEV and cEV protein profiles concerning disease status, time, and ROPI administration. Moreover, the sEV and cEV protein profiles converged over time in SALS patients, at least in part, suggestive of a loosening of the blood–brain barrier. In SALS patients, both sEVs and cEVs presented elevated inflammation-related protein levels but reduced levels of proteins associated with the unfolded protein response. These results mirrored the longitudinal changes after disease onset and correlated with the revised ALS Functional Rating Scale at sampling time, suggesting a link to the onset and progression of SALS. ROPI appeared to counteract these changes, attenuating inflammation-related protein levels and boosting those tied to the unfolded protein response in SALS, suggesting an anti-ALS effect on EV protein profiles. Reverse translational research using induced pluripotent stem cell-derived astrocytes indicated that these changes may partly reflect the DRD2-dependent neuroinflammatory inhibitory effects of ROPI. Baseline levels of OGN in sEVs and FRMPD1 in cEVs correlated with subsequent disease progression, indicating their potential as prognostic biomarkers for SALS. Machine learning-driven biomarker searches and diagnostic classification yielded an accuracy of 90.4% for sEVs and 80.3% for cEVs. Despite the limited sample size, this study is the first to report time-series proteomic alterations in sEVs and cEVs from SALS patients, offering comprehensive insights into SALS pathogenesis, ROPI-induced changes, and potential prognostic and diagnostic biomarkers.
Project description:Aim: Amyotrophic lateral sclerosis (ALS) is a heterogeneous neurodegenerative disease with limited therapeutic options. A key factor limiting the development of effective therapeutics is the lack of disease biomarkers. We sought to assess whether biomarkers for diagnosis, prognosis or cohort stratification could be identified by RNA sequencing (RNA-seq) of ALS patient peripheral blood. Methods: Whole blood RNA-seq data were generated for 96 Australian sporadic ALS (sALS) cases and 48 healthy controls (NCBI GEO accession GSE234297). Differences in sALS-control gene expression, transcript usage and predicted leukocyte proportions were assessed, with pathway analysis used to predict the activity state of biological processes. Weighted Gene Co-expression Network Analysis (WGCNA) and machine learning algorithms were applied to search for diagnostic and prognostic gene expression patterns. Unsupervised clustering analysis was employed to determine whether sALS patient subgroups could be detected. Results: 245 differentially expressed genes were identified in sALS patients relative to controls, with enrichment of immune, metabolic and stress related pathways. sALS patients also demonstrated switches in transcript usage across a small set of genes. We established a classification model that distinguished sALS from controls with an accuracy of 78% (sensitivity: 79%, specificity: 75%) using the expression of 20 genes. Clustering analysis identified four patient subgroups with gene expression signatures and immune cell proportions reflective of distinct peripheral effects. Conclusions: Our findings suggest that peripheral blood RNA-seq can identify diagnostic biomarkers and distinguish molecular subtypes of sALS patients however, its prognostic value requires further investigation.
Project description:Knowledge about the nature and timepoint of pathomolecular alterations preceding onset of symptoms in amyotrophic lateral sclerosis (ALS) is largely lacking. It could not only pave the way for valuable therapeutic targets but might also govern future concepts of pre-manifest disease modifying treatments. MicroRNAs (miRNAs) are central regulators of transcriptome plasticity and participate in pathogenic cascades and/or mirror cellular adaptation to insults. We obtained expression profiles of miRNAs as well as other non-coding RNAs (ncRNAs) in the serum of sporadic ALS patients (sALS), familial ALS cases (fALS), asymptomatic mutation carriers and healthy controls. We observed a strikingly homogenous ncRNA profile in fALS patients that, to a large extend, was independent to the underlying disease gene and different to heterogeneous ncRNA signatures in sALS patients. Moreover, we identified 68 significantly dysregulated ncRNAs in pre-manifest ALS mutation carriers, more than 20 years before the estimated time window of disease onset. 91% of ncRNA alterations in mutation carriers overlapped with the fALS patients revealing progressive changes towards and during the disease. Our data thus demonstrate a high epigenetic heterogeneity amongst sALS patients and suggest common denominators regarding molecular pathogenesis of different ALS genes. We describe the earliest pathomolecular alterations in ALS known to date, which provide a basis for the development of predictors of disease onset as well as the discovery of novel therapeutic targets and strongly argue for studies evaluating pre-symptomatic disease-modifying treatment in ALS. Serum ncRNA pofiles of sporadic and familiar ALS patients as well as asymptomatic ALS mutation carriers were compared to age and gender matched healthy controls using a total of 53 Affymetrix miRNA 3.0 arrays. In detail, a total of 9 fALS patients (analyzed in 6 arrays) were compared to 10 controls, a total of 18 ALS mutation carriers (analyzed in 12 arrays) were compared to 8 controls and 18 sALS patients were compared to 16 controls.
Project description:Extracellular vesicles (EVs) are released by neurons and glia reach the cerebrospinal fluid (CSF). Studying the proteome of CSF-derived EVs offers a novel perspective on the key intracellular processes associated with the pathogenesis of the neurodegenerative disease amyotrophic lateral sclerosis (ALS) and a potential source from which to develop biomarkers. CSF EVs were extracted using ultrafiltration liquid chromatography from ALS patients and controls. EV size distribution and concentration was measured using nanoparticle tracking analysis and liquid chromatography-tandem mass spectrometry proteomic analysis performed. CSF EV concentration and size distribution did not differ between ALS and control groups, nor between a sub-group of ALS patients with or without an associated hexanucleotide repeat expansion (HRE) in C9orf72. Univariate proteomic analysis identified downregulation of the pentameric proteasome-like protein Bleomycin hydrolase in ALS patients, whilst Gene Ontology enrichment analysis demonstrated downregulation of proteasome core complex proteins (8/8 proteins, normalized enrichment ratio -1.77, FDR-adjusted p = 0.057) in the ALS group. The sub-group of ALS patients associated with the C9orf72 HRE showed upregulation in Ubiquitin-like modifying-activating protein 1 (UBA1) compared to non-C9orf72 cases. Proteomic analysis of CSF EVs in ALS detects intracellular alterations in protein homeostatic mechanisms, previously only identified in pathological tissues. This supports the wider use of CSF EVs as a source of novel biomarkers reflecting key and potentially druggable pathological intracellular pathway alterations in ALS.
Project description:(1) Background: Blood-based biomarkers for motor neuron disease are needed for better di-agnosis, progression prediction, and clinical trial monitoring. We used whole blood-derived total RNA and performed whole transcriptome analysis to compare the gene expression pro-files in (motor neurone disease) MND patients to the control subjects. (2) Methods: We com-pared 42 MND patients to 42 aged and sex-matched healthy controls and described the whole transcriptome profile characteristic for MND. In addition to the formal differential analysis, we performed functional annotation of the genomics data and identified the molecular path-ways that are differentially regulated in MND patients. (3) Results: We identified 12,972 genes differentially expressed in the blood of MND patients compared to age and sex-matched con-trols. Functional genomic annotation identified activation of the pathways related to neuro-degeneration, RNA transcription, RNA splicing and extracellular matrix reorganisation. (4) Conclusions: Blood-based whole transcriptomic analysis can reliably differentiate MND pa-tients from controls and can provide useful information for the clinical management of the disease and clinical trials.
Project description:Background Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease associated with motor neuron degeneration, muscle atrophy and paralysis. To date, multiple panels of biomarkers have been described in ALS patients and murine models. Nevertheless, none of them has sufficient specificity and thus the molecular signature for ALS prognosis and progression remains to be fully elucidated. Circulating microRNAs (miRNAs) are highly stable molecules that are recently used as promising biomarkers for many types of human cancer and muscle disorders. Here we overcome this limitation through a longitudinal study, analyzing serum levels of circulating miRNAs in ALS patients during the progression of the pathology. Method We performed next-generation sequencing (NGS) analysis and absolute RT quantification of serum samples of 27 ALS patients and 11 healthy control; among them 13 ALS patients were studied every three months till the end of the disease. Results We demonstrated that miR-151a-3p, miR-206 and miR-199a-3p are significantly expressed at the mild, moderate and severe stages of ALS pathology, whereas the expression levels of miR-133a and miR-199a-5p remained low during the whole study and retain diagnostic significance in the moderate and severe stages (miR-133a) and in mild and terminal stages (miR-199a-5p) of the disease. Moreover, we analysed the miRNAs serum levels during the progression of the disease in each patient and we demonstrated that high levels of miR-206, miR-133a, miR-151a-5p, miR-151a-3p can predict a slower clinical decline of patient functionality suggesting that these miRNAs represent good potential prognostic markers for ALS disease. Conclusion This study is the first to perform a longitudinal absolute quantification of circulating miRNAs during ALS disease. We highlighted putative biomarkers for diagnosis, prognosis and disease stage identification of ALS patients providing cut-off threshold for most of the miRNAs analyzed. In addition, our results define a molecular signature of ALS phenotypes that could help to define appropriate enrollments of patients in clinical trials.
Project description:We established several iPSCs from healthy donors, familial ALS (FALS) patients, and sporadic ALS (SALS) patients. Using our differentiation protocol originally developed, we differentiated these iPSCs toward spinal motor neurons (MNs) and reproduced ALS pathology in a dish. In addition, we screened a drug candidate which suppressed the detected ALS-related phenotypes of these ALS models. For clarifying the molecular mechanisms of the ALS pathologies and the screened drug, we used microarrays to detail the global program of gene expression reflecting the MN pathology of FALS/SALS, and carefully compared with healthy donors and/or drug-treated ALS models based on their expression profiles.
Project description:Knowledge about the nature and timepoint of pathomolecular alterations preceding onset of symptoms in amyotrophic lateral sclerosis (ALS) is largely lacking. It could not only pave the way for valuable therapeutic targets but might also govern future concepts of pre-manifest disease modifying treatments. MicroRNAs (miRNAs) are central regulators of transcriptome plasticity and participate in pathogenic cascades and/or mirror cellular adaptation to insults. We obtained expression profiles of miRNAs as well as other non-coding RNAs (ncRNAs) in the serum of sporadic ALS patients (sALS), familial ALS cases (fALS), asymptomatic mutation carriers and healthy controls. We observed a strikingly homogenous ncRNA profile in fALS patients that, to a large extend, was independent to the underlying disease gene and different to heterogeneous ncRNA signatures in sALS patients. Moreover, we identified 68 significantly dysregulated ncRNAs in pre-manifest ALS mutation carriers, more than 20 years before the estimated time window of disease onset. 91% of ncRNA alterations in mutation carriers overlapped with the fALS patients revealing progressive changes towards and during the disease. Our data thus demonstrate a high epigenetic heterogeneity amongst sALS patients and suggest common denominators regarding molecular pathogenesis of different ALS genes. We describe the earliest pathomolecular alterations in ALS known to date, which provide a basis for the development of predictors of disease onset as well as the discovery of novel therapeutic targets and strongly argue for studies evaluating pre-symptomatic disease-modifying treatment in ALS.