Identification of serum microRNA signatures associated with autism spectrum disorder as promising candidate biomarkers

Autism spectrum disorder: difficulties in diagnosis and microRNA biomarkers

We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023, of which 4 studies were performed with whole blood, 4 with blood plasma, 5 with blood serum, 1 with serum neural cell adhesion molecule L1-captured extracellular vesicles, 1 with blood cells, and 2 with peripheral blood mononuclear cells. Most of the studies involved children and the study cohorts were largely males. Many of the studies had performed microRNA sequencing or quantitative polymerase chain reaction assays to measure microRNA expression. Only five studies had used real-time polymerase chain reaction assay to validate microRNA expression in autism spectrum disorder subjects compared to controls. The microRNAs that were validated in these studies may be considered as potential candidate biomarkers for autism spectrum disorder and include miR-500a-5p, -197-5p, -424-5p, -664a-3p, -365a-3p, -619-5p, -664a-3p, -3135a, -328-3p, and -500a-5p in blood plasma and miR-151a-3p, -181b-5p, -320a, -328, -433, -489, -572, -663a, -101-3p, -106b-5p, -19b-3p, -195-5p, and -130a-3p in blood serum of children, and miR-15b-5p and -6126 in whole blood of adults. Several important limitations were identified in the studies reviewed, and need to be taken into account in future studies. Further studies are warranted with children and adults having different levels of autism spectrum disorder severity and consideration should be given to using animal models of autism spectrum disorder to investigate the effects of suppressing or overexpressing specific microRNAs as a novel therapy.

Expression of miR-195-5p in the serum of children with autism spectrum disorder and its correlation with the severity of the disease

OBJECTIVE

The target of this research was to explore the serum miR-195-5p expression in children with autism spectrum disorder (ASD) and its association with the disease severity.

METHODS

The research enrolled 30 ASD children as the study group and 30 typically developing children as the control group. MiR-195-5p and FGFR1 were detected in the serum and cells of subjects via real-time quantitative PCR (RT-qPCR). The diagnostic values of miR-195-5p and FGFR1 were assessed using receiver operating characteristic (ROC) curves. The Pearson correlation coefficient was employed to assess the relationship between miR-195-5p and childhood autism rating scale (CARS), autism behavior checklist (ABC), and Clancy autism behavior scale (CABS) scores, as well as the correlation between miR-195-5p and FGFR1. Bioinformatics was utilized to predict the miR-195-5p-targeted gene. The interaction between miR-195-5p and FGFR1 was validated through luciferase reporter assay.

RESULTS

Serum miR-195-5p levels were significantly increased in ASD children (P < 0.001). The ROC results indicated that miR-195-5p had the ability to differentiate between ASD children and control groups. The Pearson correlation coefficient confirmed that miR-195-5p was positively correlated with the CARS score (r = 0.6699), ABC score (r = 0.5386), and CABS score (r = 0.7096). Luciferase reporter experiments and RT-qPCR demonstrated that FGFR1 served as a downstream target gene of miR-195-5p. Further studies revealed that FGFR1 levels were decreased in ASD children (P < 0.001) and FGFR1 exhibited a negative correlation with miR-195-5p. The ROC results signified that FGFR1 could also distinguish ASD children from the control group.

CONCLUSION

Serum miR-195-5p was elevated in ASD children and was positively associated with the disease severity. MiR-195-5p might function as a diagnostic and treatment target for ASD.

Deregulated mRNA and microRNA Expression Patterns in the Prefrontal Cortex of the BTBR Mouse Model of Autism

Autism spectrum disorder (ASD) is a neurodevelopmental condition caused by both genetic and environmental factors. Since no single gene variant accounts for more than 1% of the cases, the converging actions of ASD-related genes and other factors, including microRNAs (miRNAs), may contribute to ASD pathogenesis. To date, few studies have simultaneously investigated the mRNA and miRNA profiles in an ASD-relevant model. The BTBR mouse strain displays a range of behaviors with ASD-like features but little is known about the protein-coding and noncoding gene expression landscape that may underlie the ASD-like phenotype. Here we performed parallel mRNA and miRNA profiling using the prefrontal cortex (PFC) of BTBR and C57BL/6 J (B6) mice. This identified 1063 differentially expressed genes and 48 differentially expressed miRNAs. Integration of mRNA and miRNA data identified a strong inverse relationship between upregulated (DEGs) and downregulated miRNAs, and vice versa. Pathway analysis, taking account of the inverse relationship between differentially expressed miRNAs and their target mRNAs highlighted significant shared enrichment in immune signaling, myelination, and neurodevelopmental processes. Notably, miRNA changes were predicted to affect synapse-related functions but we did not find enrichment of protein-coding genes linked to cellular components or biological processes related to synapses in the PFC of BTBR mice, indicating processes may evade miRNA control. In contrast, other miRNAs were predicted to have extensive relationships with DEGs suggesting their role as potential hub coordinators of gene expression. Profiling findings were confirmed via qRT-PCR for representative protein-coding transcripts and miRNAs. Our study underscores the complex interplay between gene expression and miRNA regulation within immune and inflammatory pathways in the BTBR model, offering insights into the neurodevelopmental mechanisms of ASD. These results support the value of the BTBR mouse model and identify strategies that could adjust molecular pathways for therapeutic applications in ASD research.

MicroRNAs as Regulators, Biomarkers, and Therapeutic Targets in Autism Spectrum Disorder

The pathogenesis of autism spectrum disorder (ASD) is complex and is mainly influenced by genetic and environmental factors. Some research has indicated that environmental aspects may interplay with genetic aspects to enhance the risk, and microRNAs (miRNAs) are probably factors in explaining this link between heredity and the environment. MiRNAs are single-stranded noncoding RNAs that can regulate gene expression at the posttranscriptional level. Some research has indicated that miRNAs are closely linked to neurological diseases. Many aberrantly expressed miRNAs have been observed in autism, and these dysregulated miRNAs are expected to be potential biomarkers and provide new strategies for the treatment of this disease. This article reviews the research progress of miRNAs in autism, including their biosynthesis and function. It is found that some miRNAs show aberrant expression patterns in brain tissue and peripheral blood of autistic patients, which may serve as biomarkers of the disease. In addition, the article explores the novel role of exosomes as carriers of miRNAs with the ability to cross the blood-brain barrier and unique expression profiles, offering new possibilities for diagnostic and therapeutic interventions in ASD. The potential of miRNAs in exosomes as diagnostic markers for ASD is specifically highlighted, as well as the prospect of using engineered exosome-encapsulated miRNAs for targeted therapies.

Machine learning uncovers novel sex-specific dementia biomarkers linked to autism and eye diseases

Background

Recently, microRNAs (miRNAs) have attracted significant interest as predictive biomarkers for various types of dementia, including Alzheimer's disease (AD), vascular dementia (VaD), dementia with Lewy bodies (DLB), normal pressure hydrocephalus (NPH), and mild cognitive impairment (MCI). Machine learning (ML) methods enable the integration of miRNAs into highly accurate predictive models of dementia.

Objective

To investigate the differential expression of miRNAs across dementia subtypes compared to normal controls (NC) and analyze their enriched biological and disease pathways. Additionally, to evaluate the use of these miRNAs in binary and multiclass ML models for dementia prediction in both overall and sex-specific datasets.

Methods

Using data comprising 1685 Japanese individuals (GSE120584 and GSE167559), we performed differential expression analysis to identify miRNAs associated with five dementia groups in both overall and sex-specific datasets. Pathway enrichment analyses were conducted to further analyze these miRNAs. ML classifiers were used to create predictive models of dementia.

Results

We identified novel differentially expressed miRNA biomarkers distinguishing NC from five dementia subtypes. Incorporating these miRNAs into ML classifiers resulted in up to a 27% improvement in dementia risk prediction. Pathway analysis highlighted neuronal and eye disease pathways associated with dementia risk. Sex-specific analyses revealed unique biomarkers for males and females, with miR-128-1-5 as a protective factor for males in AD, VaD, and DLB, and miR-4488 as a risk factor for female AD, highlighting distinct pathways and potential therapeutic targets for each sex.

Conclusions

Our findings support existing dementia etiology research and introduce new potential and sex-specific miRNA biomarkers.

Expression of miRNAs in Pre-Schoolers with Autism Spectrum Disorders Compared with Typically Developing Peers and Its Effects after Probiotic Supplementation

Alteration of the microbiota-gut-brain axis has been recently recognized as a possible contributor to the physiopathology of autism spectrum disorder (ASD). In this context, microRNA (miRNAs) dysfunction, implicated both in several neuropathological conditions including ASD and in different gastrointestinal disorders (GIDs), could represent an important modulating factor. In this contextual framework, we studied the transcriptional profile of specific circulating miRNAs associated with both ASD (miR-197-5p, miR-424-5p, miR-500a-5p, miR-664a-5p) and GID (miR-21-5p, miR-320a-5p, miR-31-5p, miR-223-5p) in a group of pre-schoolers with ASD and in typically developing (TD) peers. In the ASD group, we also assessed the same miRNAs after a 6-month supplementation with probiotics and their correlation with plasma levels of zonulin and lactoferrin. At baseline, the expression of miRNAs involved in ASD were significantly reduced in ASD pre-schoolers vs. TD controls. Regarding the miRNAs involved in GID, the expression levels of miR-320-5p, miR-31-5p, and miR-223-5p were significantly higher in ASD than in TD subjects, whereas miR-21-5p showed significantly reduced expression in the ASD group vs. TD group. Supplementation with probiotics did not significantly change the expression of miRNAs in the ASD population. We found a significative negative correlation between zonulin and miR-197-5p and miR-21-5p at baseline, as well as between lactoferrin and miR-223-5p after 6 months of probiotic supplementation. Our study confirms the presence of an altered profile of the miRNAs investigated in ASD versus TD peers that was not modified by supplementation with probiotics.

The role of Extracellular Genomic Materials (EGMs) in psychiatric disorders

Extracellular Genomic Materials (EGMs) are the nucleic acids secreted or released from all types of cells by endogenous or exogenous stimuli through varying mechanisms into the extracellular region and inevitably to all biological fluids. EGMs could be found as free, protein-bound, and/ or with vesicles. EGMs can potentially have immunophenotypic and/or genotypic characteristics of a cell of origin, travel to distant organs, and interact with the new microenvironment. To achieve all, EGMs might bi-directionally transit through varying membranes, including the blood-brain barrier. Such ability provides the transfer of any information related to the pathophysiological changes in psychiatric disorders in the brain to the other distant organ systems or vice versa. In this article, many aspects of EGMs have been elegantly reviewed, including their potential in diagnosis as biomarkers, application in treatment modalities, and functional effects in the pathophysiology of psychiatric disorders. The psychiatric disorders were studied under subgroups of Schizophrenia spectrum disorders, bipolar disorder, depressive disorders, and an autism spectrum disorders. EGMs provide a robust and promising tool in clinics for prognosis and diagnosis. The successful application of EGMs into treatment modalities might further provide encouraging outcomes for researchers and clinicians in psychiatric disorders.

Differentiation value of miR-26b for major depressive disorder, schizophrenia, generalized anxiety disorder

Introduction

First episode and drug naive schizophrenia (SZ) patients comorbid with major depressive episode and generalized anxiety disorder (GAD) comorbid with major depressive disorder (MDD) are common in clinical practice, overlapping symptomatology during first presentation of MDD, SZ and GAD challenged the diagnostic process.

Materials and Methods

This study aimed to investigate the differentiation value of peripheral microRNA-26b expression in 52 patients of MDD, SZ, and GAD, respectively, and 52 controls. Quantitative real-time reverse transcription polymerase chain reaction was used to further verify aberrant miRNAs of previous identified in MDD and investigate expression level of these peripheral miRNAs in SZ and GAD.

Results

The expression levels of miR-26b and miR-4743 were significantly upregulated and of miR-4498, miR-4485, and miR-1972 had no significant difference. There were no significant differences of expression levels of miR-26b, miR-4498, miR-4485, and miR-1972 except miR-4743 between SZ patients and control group and of miR-26b, miR-1972, miR-4498, and miR-4485 between GAD group and the controls. The receiver operating characteristic (ROC) curve of miR-26b in MDD patients showed that its sensitivity and specificity for diagnosis were 0.540 and 0.830, respectively, with the area under curve (AUC) being 0.728; the ROC of miR-26b for SZ and MDD differentiation showed that its sensitivity and specificity were 0.580 and 0.710, respectively, with AUC being 0.631; the ROC of miR-26b for GAD and MDD differentiation suggested that sensitivity and specificity were 0.560 and 0.750, respectively, with AUC being 0.637.

Conclusion

MiR-26b might have potential value of differentiation biomarker for MDD, SZ, and GAD.

Salivary microRNA profiling dysregulation in autism spectrum disorder: A pilot study

INTRODUCTION

Autism spectrum disorders (ASD) are the most prevalent neurobiological disorders in children. The etiology comprises genetic, epigenetic, and environmental factors such as dysfunction of the immune system. Epigenetic mechanisms are mainly represented by DNA methylation, histone modifications, and microRNAs (miRNA). The major explored epigenetic mechanism is mediated by miRNAs which target genes known to be involved in ASD pathogenesis. Salivary poly-omic RNA measurements have been associated with ASD and are helpful to differentiate ASD endophenotypes. This study aims to comprehensively examine miRNA expression in children with ASD and to reveal potential biomarkers and possible disease mechanisms so that they can be used to improve faction between individuals by promoting more personalized therapeutic approaches.

MATERIALS AND METHODS

Saliva samples were collected from 10 subjects: 5 samples of children with ASD and 5 from healthy controls. miRNAs were analyzed using an Illumina Next-Generation-Sequencing (NGS) system.

RESULTS

Preliminary data highlighted the presence of 365 differentially expressed miRNAs. Pathway analysis, molecular function, biological processes, and target genes of 41 dysregulated miRNAs were assessed, of which 20 were upregulated, and 21 were downregulated in children with ASD compared to healthy controls.

CONCLUSION

The results of this study represent preliminary but promising data, as the identified miRNA pathways could represent useful biomarkers for the early non-invasive diagnosis of ASD.

Evaluation of circulating miRNAs and mRNAs expression patterns in autism spectrum disorder

Background

Autism spectrum disorder is a condition related to brain development that affects a person’s perception and socialization, resulting in problems in social interaction and communication. It has no single known cause, yet several different genes appear to be involved in autism. As a genetically complex disease, dysregulation of miRNA expression and miRNA–mRNA interactions might be a feature of autism spectrum disorder. The aim of the current study was to investigate the expression profile of circulating miRNA-128, miRNA-7 and SHANK gene family in ASD patients and to assess the possible influence of miRNA-128 and miRNA-7 on SHANK genes, which might provide an insight into the pathogenic mechanisms of ASD and introduce noninvasive molecular biomarkers for the disease diagnosis and prognosis. Quantitative real-time PCR technique was employed to determine expression levels of miRNA-128, miRNA-7 and SHANK gene family in blood samples of 40 autistic cases along with 30 age- and sex-matched normal volunteer subjects.

Results

Our study revealed a statistical significant upregulation of miRNA-128 expression levels in ASD cases compared to controls (p value < 0.001). A statistical significant difference in SHANK-3 expression was encountered on comparing cases to controls (p value < 0.001). However, miRNA-7 expression showed no significant difference between the studied groups.

Conclusions

MiRNA-128 and SHANK-3 gene are emerging players in the field of ASD. They are promising candidates as noninvasive biomarkers in autism. Future studies are needed to emphasize their pivotal role.

Emerging Role of Non-coding RNAs in Autism Spectrum Disorder

Autism spectrum disorders (ASD) embrace a diverse set of neurodevelopmental diseases with a multifaceted genetic basis. Non-coding RNAs (ncRNAs) are among putative loci with critical participation in the development of ASD. Expression of some lncRNAs, namely RP11-466P24.2, SYP-AS1, STXBP5-AS1, and IFNG-AS1 has been decreased in ASD, while AK128569, CTD-2516F10.2, MSNP1AS, RPS10P2-AS1, LINC00693, LINC00689, NEAT1, TUG1, and Shank2-AS lncRNAs have been over-expressed in ASD. Expression of several miRNAs which are implicated in the immunological developmental, immune responses, and protein synthesis as well as those participating in the regulation of PI3K/Akt/mTOR and EGFR signaling pathways is dysregulated in the context of ASD. In the present article, we describe investigations which appraised the role of lncRNAs, miRNAs, and circRNAs in the pathobiology of ASD.