IFNG/IFNG-AS1 expression level balance: implications for autism spectrum disorder

The function of long non-coding RNA IFNG-AS1 in autoimmune diseases

The prevalence of autoimmune diseases ranks as the third most common disease category globally, following cancer and heart disease. Numerous studies indicate that long non-coding RNA (lncRNA) plays a pivotal role in regulating human growth, development, and the pathogenesis of various diseases. It is more than 200 nucleotides in length and is mostly involve in the regulation of gene expression. Furthermore, lncRNAs are crucial in the development and activation of immune cells, with an expanding body of research exploring their association with autoimmune disorders in humans. LncRNA Ifng antisense RNA 1 (IFNG-AS1), a key regulatory factor in the immune system, also named NeST or TMEVPG1, is proximally located to IFNG and participates in the regulation of it. The dysregulation of IFNG-AS1 is implicated in the pathogenesis of several autoimmune diseases. This study examines the role and mechanism of IFNG-AS1 in various autoimmune diseases and considers its potential as a therapeutic target.

Exosome lncRNA IFNG-AS1 derived from mesenchymal stem cells of human adipose ameliorates neurogenesis and ASD-like behavior in BTBR mice

BACKGROUND

The transplantation of exosomes derived from human adipose-derived mesenchymal stem cells (hADSCs) has emerged as a prospective cellular-free therapeutic intervention for the treatment of neurodevelopmental disorders (NDDs), as well as autism spectrum disorder (ASD). Nevertheless, the efficacy of hADSC exosome transplantation for ASD treatment remains to be verified, and the underlying mechanism of action remains unclear.

RESULTS

The exosomal long non-coding RNAs (lncRNAs) from hADSC and human umbilical cord mesenchymal stem cells (hUCMSC) were sequenced and 13,915 and 729 lncRNAs were obtained, respectively. The lncRNAs present in hADSC-Exos encompass those found in hUCMSC-Exos and are associated with neurogenesis. The biodistribution of hADSC-Exos in mouse brain ventricles and organoids was tracked, and the cellular uptake of hADSC-Exos was evaluated both in vivo and in vitro. hADSC-Exos promote neurogenesis in brain organoid and ameliorate social deficits in ASD mouse model BTBR T + tf/J (BTBR). Fluorescence in situ hybridization (FISH) confirmed lncRNA Ifngas1 significantly increased in the prefrontal cortex (PFC) of adult mice after hADSC-Exos intraventricular injection. The lncRNA Ifngas1 can act as a molecular sponge for miR-21a-3p to play a regulatory role and promote neurogenesis through the miR-21a-3p/PI3K/AKT axis.

CONCLUSION

We demonstrated hADSC-Exos have the ability to confer neuroprotection through functional restoration, attenuation of neuroinflammation, inhibition of neuronal apoptosis, and promotion of neurogenesis both in vitro and in vivo. The hADSC-Exos-derived lncRNA IFNG-AS1 acts as a molecular sponge and facilitates neurogenesis via the miR-21a-3p/PI3K/AKT signaling pathway, thereby exerting a regulatory effect. Our findings suggest a potential therapeutic avenue for individuals with ASD.

Immunogenetics of autism spectrum disorder: A systematic literature review

The aetiology of autism spectrum disorder (ASD) is complex and, partly, accounted by genetic factors. Nonetheless, the genetic underpinnings of ASD are poorly defined. The presence of immune dysregulations in autistic individuals, and their families, supports a role of the immune system and its genetic regulators. Albeit immune responses belong either to the innate or adaptive arms, the overall immune system genetics is broad, and encompasses a multitude of functionally heterogenous pathways which may have different influences on ASD. Hence, to gain insights on the immunogenetic underpinnings of ASD, we conducted a systematic literature review of previous immune genetic and transcription studies in ASD. We defined a list of immune genes relevant to ASD and explored their neuro-immune function. Our review confirms the presence of immunogenetic variability in ASD, accounted by inherited variations of innate and adaptive immune system genes and genetic expression changes in the blood and post-mortem brain of autistic individuals. Besides their immune function, the identified genes control neurodevelopment processes (neuronal and synaptic plasticity) and are highly expressed in pre/peri-natal periods. Hence, our synthesis bolsters the hypothesis that perturbation in immune genes may contribute to ASD by derailing the typical trajectory of neurodevelopment. Our review also helped identifying some of the limitations of prior immunogenetic research in ASD. Thus, alongside clarifying the neurodevelopment role of immune genes, we outline key considerations for future work into the aetiology of ASD and possible novel intervention targets.

Investigation of LncRNA PVT1 and MiR-21-5p Expression as Promising Novel Biomarkers for Autism Spectrum Disorder

The characteristics of ncRNA in children with autism spectrum disorder (ASD) were observed to disclose a theoretical basis for further research on molecular markers for early warning of ASD. Children with ASD and normal control children were recruited to collect peripheral blood RNA samples. The concentration of PVT1 and miR-21-5p was quantitatively analyzed by qRT-PCR. Pearson correlation coefficient method was used to evaluate the link between PVT1 level and miR-21-5p level of the children. Receiver operating characteristic (ROC) curves were applied to reckon the predictive value of PVT1, miR-21-5p, and their combination in ASD. The interconnection of PVT1 with miR-21-5p was represented by luciferase reporter assay. The targeted genes of miR-21-5p were predicted. The enrichment and protein interaction analysis of these genes was carried out to find the important core genes and analyze their value in ASD. In the disease group, the level of PVT1 was downregulated, while the content of miR-21-5p was upregulated. The expression level of serum miR-21-5p was negatively correlated with the level of PVT1. Luciferase reporter gene assay documented that PVT1 directly targeted miR-21-5p. ROC curve showed that PVT1, miR-21-5p, and their combination showed clinical value for disease diagnosis. The functional enrichment analysis showed that the targets of miR-21-5p participated in ASD by regulating related functions and pathways. Reduced expression of PVT1 and raised miR-21-5p were good diagnostic markers for ASD, which would provide a basis for effective prevention, early diagnosis, and early intervention of ASD.

Hypoxia-induced LncRNA DACT3-AS1 upregulates PKM2 to promote metastasis in hepatocellular carcinoma through the HDAC2/FOXA3 pathway

Growing evidence has revealed that hypoxia is involved in multiple stages of cancer development. However, there are limited reports on the effects of long noncoding RNAs (lncRNAs) on hepatocellular carcinoma (HCC) progression under hypoxia. The main purposes of this study were to analyze the effect of the novel lncRNA DACT3-AS1 on metastasis in HCC and to elucidate the related molecular mechanism. Bioinformatics tools were employed. RT–qPCR or western blot assays were conducted to detect RNA or protein expression. Clinical samples and in vivo assays were utilized to reveal the role of DACT3-AS1 in HCC. Other mechanism and functional analyses were specifically designed and performed as well. Based on the collected data, this study revealed that HIF-1α transcriptionally activates DACT3-AS1 expression under hypoxia. DACT3-AS1 was verified to promote metastasis in HCC. Mechanistically, DACT3-AS1 promotes the interaction between HDAC2 and FOXA3 to stimulate FOXA3 deacetylation, which consequently downregulates the FOXA3 protein. Furthermore, FOXA3 serves as a transcription factor that can bind to the PKM2 promoter region, thus hindering PKM2 expression. To summarize, this study uncovered that HIF-1α-induced DACT3-AS1 promotes metastasis in HCC and can upregulate PKM2 via the HDAC2/FOXA3 pathway in HCC cells.

Understanding the role of an RNA molecule involved in metastasis (spread) of liver cancer may suggest potential therapeutic targets. Hepatocarcinoma is a common primary liver cancer, and mortality remains high due to late diagnosis and the risk of metastasis. Scientists believe hypoxic (low oxygen) conditions in solid tumors may trigger metastasis by a mechanism involving long non-coding RNAs. Bin Li and co-workers at the Affiliated Hospital of Guilin Medical College, China, used patient tissue samples to examine the role of the long non-coding RNA molecule DACT3-AS1 in promoting hepatocarcinoma metastasis. Hypoxia triggers the overexpression of HIF-1α. This protein activated DACT3-AS1, which was then highly expressed in metastatic tissues. DACT3-AS1 interacted with a nearby gene and associated enzyme to promote cell migration and invasion, hinting at possible treatment options.

The correlation of long non-coding RNAs IFNG-AS1 and ZEB2-AS1 with IFN-γ and ZEB-2 expression in PBMCs and clinical features of patients with coronary artery disease

BACKGROUND

Aberrant expression of long non-coding RNAs (lncRNAs) can contribute to the pathogenesis of coronary artery disease (CAD). In this study, we aimed to evaluate the expression of lncRNA interferon γ-antisense 1 (IFNG-AS1), zinc finger E-box binding homeobox 2 antisense RNA 1 (ZEB2-AS1), and their direct target genes (IFN-γ and ZEB2, respectively) in peripheral blood mononuclear cell (PBMC) from CAD and healthy individuals.

METHODS AND RESULTS

We recruited 40 CAD patients and 40 healthy individuals. After doing some bioinformatics analyses, the expressions of IFNG-AS1/ ZEB2-AS1 lncRNAs and IFN-γ/ ZEB2 in PBMCs were measured using quantitative real-time PCR. The possible correlation between the putative lncRNAs and disease severity was also assessed. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive role of lncRNAs as diagnostic biomarkers in CAD patients. The expressions of IFNG-AS1 lncRNA as well as IFN-γ and ZEB2 genes were significantly reduced in CAD patients compared to healthy subjects. In contrast, the expression of ZEB2-AS1 was up-regulated in these patients. Linear regression analysis unveiled that there is a positive correlation between the expression of IFNG-AS1 and IFN-γ, also similarly, ZEB2-AS1 and ZEB2 in PBMCs of subjects. Moreover, the expression of IFNG-AS1 and ZEB2-AS1 correlated with the Gensini score. The area under the ROC curves ranged from 0.633-0.742 for ZEB2-AS1/ZEB2 and IFNG-AS1/IFN-γ, respectively.

CONCLUSIONS

Our results indicated that the dysregulation of IFNG-AS1/IFN-γ and ZEB2-AS1/ZEB2 in PBMCs of CAD patients may be involved in CAD pathogenesis.

Re-emerging concepts of immune dysregulation in autism spectrum disorders

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by communication and social interaction deficits, and by restricted interests and stereotyped, repetitive behavior patterns. ASD has a strong genetic component and a complex architecture characterized by the interplay of rare and common genetic variants. Recently, increasing evidence suggest a significant contribution of immune system dysregulation in ASD. The present paper reviews the latest updates regarding the altered immune landscape of this complex disorder highlighting areas with potential for biomarkers discovery as well as personalization of therapeutic approaches. Cross-talk between the central nervous system and immune system has long been envisaged and recent evidence brings insights into the pathways connecting the brain to the immune system. Disturbance of cytokine levels plays an important role in the establishment of a neuroinflammatory milieu in ASD. Several other immune molecules involved in antigen presentation and inflammatory cellular phenotypes are also at play in ASD. Maternal immune activation, the presence of brain-reactive antibodies and autoimmunity are other potential prenatal and postnatal contributors to ASD pathophysiology. The molecular players involved in oxidative-stress response and mitochondrial system function, are discussed as contributors to the pro-inflammatory pattern. The gastrointestinal inflammation pathways proposed to play a role in ASD are also discussed. Moreover, the body of evidence regarding some of the genetic factors linked to the immune system dysregulation is reviewed and discussed. Last, but not least, the epigenetic traits and their interactions with the immune system are reviewed as an expanding field in ASD research. Understanding the immune-mediated pathways that influence brain development and function, metabolism, and intestinal homeostasis, may lead to the identification of robust diagnostic or predictive biomarkers for ASD individuals. Thus, novel therapeutic approaches could be developed, ultimately aiming to improve their quality of life.

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.

Decoding LncRNAs

Non-coding RNAs (ncRNAs) have been considered as unimportant additions to the transcriptome. Yet, in light of numerous studies, it has become clear that ncRNAs play important roles in development, health and disease. Long-ignored, long non-coding RNAs (lncRNAs), ncRNAs made of more than 200 nucleotides have gained attention due to their involvement as drivers or suppressors of a myriad of tumours. The detailed understanding of some of their functions, structures and interactomes has been the result of interdisciplinary efforts, as in many cases, new methods need to be created or adapted to characterise these molecules. Unlike most reviews on lncRNAs, we summarize the achievements on lncRNA studies by taking into consideration the approaches for identification of lncRNA functions, interactomes, and structural arrangements. We also provide information about the recent data on the involvement of lncRNAs in diseases and present applications of these molecules, especially in medicine.

Genetic and molecular biology of autism spectrum disorder among Middle East population: a review

BACKGROUND

Autism spectrum disorder (ASD) is a neurodevelopmental disease, characterized by impaired social communication, executive dysfunction, and abnormal perceptual processing. It is more frequent among males. All of these clinical manifestations are associated with atypical neural development. Various genetic and environmental risk factors are involved in the etiology of autism. Genetic assessment is essential for the early detection and intervention which can improve social communications and reduce abnormal behaviors. Although, there is a noticeable ASD incidence in Middle East countries, there is still a lack of knowledge about the genetic and molecular biology of ASD among this population to introduce efficient diagnostic and prognostic methods.

MAIN BODY

In the present review, we have summarized all of the genes which have been associated with ASD progression among Middle East population. We have also categorized the reported genes based on their cell and molecular functions.

CONCLUSIONS

This review clarifies the genetic and molecular biology of ASD among Middle East population and paves the way of introducing an efficient population based panel of genetic markers for the early detection and management of ASD in Middle East countries.

Critical regulation of a NDIME/MEF2C axis in embryonic stem cell neural differentiation and autism

A microdeletion within human chromosome 5q14.3 has been associated with the occurrence of neurodevelopmental disorders, such as autism and intellectual disability, and MEF2C haploinsufficiency was identified as main cause. Here, we report that a brain-enriched long non-coding RNA, NDIME, is located near the MEF2C locus and is required for normal neural differentiation of mouse embryonic stem cells (mESCs). NDIME interacts with EZH2, the major component of polycomb repressive complex 2 (PRC2), and blocks EZH2-mediated trimethylation of histone H3 lysine 27 (H3K27me3) at the Mef2c promoter, promoting MEF2C transcription. Moreover, the expression levels of both NDIME and MEF2C were strongly downregulated in the hippocampus of a mouse model of autism, and the adeno-associated virus (AAV)-mediated expression of NDIME in the hippocampus of these mice significantly increased MEF2C expression and ameliorated autism-like behaviors. The results of this study reveal an epigenetic mechanism by which NDIME regulates MEF2C transcription and neural differentiation and suggest potential effects and therapeutic approaches of the NDIME/MEF2C axis in autism.