Long non-coding RNA ANRIL knockdown suppresses apoptosis and pro-inflammatory cytokines while enhancing neurite outgrowth via binding microRNA-125a in a cellular model of Alzheimer's disease

A review on the lncRNA-miRNA-mRNA regulatory networks involved in inflammatory processes in Alzheimer's disease

Alzheimer's disease is a progressive neurodegenerative condition that is the most frequent reason for dementia. Due to the increasing trend of aging in societies, it will place a large social and financial burden on society. Although beta amyloid plaques and the formation of neurofibrillary tangles are mentioned as the main events in this disorder, the exact molecular pathology and inflammatory regulatory networks involved in neuroinflammatory events, as a fundamental pathogenic mechanism remain unknown. Understanding these molecular network pathways in addition to helping to understand the pathogenesis of Alzheimer's disease, can also help in the early diagnosis as well as the control of inflammatory processes that are involved in its progression. So, in this study, we intend to have an overview on the regulatory lncRNAs of Alzheimer's disease and their related miRNA and mRNAs, as well as the relationship of these regulatory pathways with inflammatory processes, so that we can provide a perspective for future studies in the field of diagnosis and possibly treatment of this disorder.

Regulation of Apoptotic Pathways by MicroRNAs: A Therapeutic Strategy for Alzheimer's Disease

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder marked by a gradual decline in memory and cognitive functions. It is characterized by the presence of senile plaques, neurofibrillary tangles, and neuronal degeneration, affecting a significant portion of the human population. A key feature of various nervous system disorders, including AD, is extensive cellular death caused by apoptosis, which affects not only neurons but also glial cells. While apoptosis plays a vital role in eliminating certain cells and supporting normal development, alterations or disruptions in apoptotic pathways can lead to harmful neurodegenerative conditions such as AD. Thus, targeting apoptosis presents a promising therapeutic approach for these diseases. MicroRNAs (miRNAs), a class of non-coding RNA, play diverse roles in cellular functions, including proliferation, gene expression regulation, programmed cell death, intercellular communication, and angiogenesis. By modulating regulatory genes, miRNAs can influence apoptosis, either promoting or inhibiting it. Aberrant expression of miRNAs can impact multiple apoptotic pathways, potentially driving the progression of AD and related health issues. This review summarizes recent research on miRNAs and their dual role in exacerbating or protecting against neural cell damage in AD by altering apoptotic pathways. The regulation of apoptosis by miRNAs offers a prospective therapeutic strategy for Alzheimer's disease.

LncRNAs Orchestrating Neuroinflammation: A Comprehensive Review

CNS diseases account for a major part of the comorbidity and mortality of the human population; moreover, neuroinflammation has become an indication for different CNS diseases, for instance, Parkinson's and Alzheimer's disease. Microglia and astrocytes are the two main glial cells that can be found in the CNS. Each of these plays an important role in mediating immune responses like inflammation. There are many studies suggesting the role of LncRNAs in mediating neuroinflammation. Indeed, LncRNAs orchestrate neuroinflammation through various mechanisms, namely miRNA sponge, and transcriptional activation/inhibition. In addition, LncRNAs regulate different downstream pathways like NF-κB, and PI3K/AKT. In this study, we gathered the existing studies regarding the mechanisms of action of LncRNAs in the pathogenesis of different CNS diseases like neurodegenerative diseases and traumatic injuries through regulating neuroinflammation. We aim to elaborate on the regulatory roles of LncRNAs in neuroinflammation and bring a more profound understanding of the etiology of CNS diseases in terms of neuroinflammation.

Non-coding RNAs in the pathogenesis of Alzheimer's disease: β-amyloid aggregation, Tau phosphorylation and neuroinflammation

Alzheimer's disease is a progressive neurodegenerative disorder primarily affecting individuals aged 65 and older, characterized by cognitive decline and diminished quality of life. The molecular hallmarks of AD include extracellular β-amyloid plaques, intracellular neurofibrillary tangles composed of hyperphosphorylated tau protein, and chronic neuroinflammation. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), have emerged as potential therapeutic targets due to their regulatory roles in AD pathogenesis. For example, miR-124 has been shown to modulate Aβ levels, while lncRNAs such as BACE1-AS regulate the expression of BACE1, a crucial enzyme in Aβ production. Transcriptomic studies of AD patients have revealed dysregulation of ncRNA expression, further supporting their involvement in disease progression. This review examines the regulatory functions of ncRNAs in AD, focusing on their impact on Aβ, tau hyperphosphorylation, and neuroinflammation. Additionally, we discuss the emerging role of ncRNAs in liquid-liquid phase separation and the formation of protein aggregates, key processes contributing to AD pathology.

Exosomes and non-coding RNAs: bridging the gap in Alzheimer's pathogenesis and therapeutics

Alzheimer's disease (AD) is a neurodegenerative disease that primarily affects the elderly population and is the leading cause of dementia. Meanwhile, the vascular hypothesis suggests that vascular damage occurs in the early stages of the disease, leading to neurodegeneration and hindered waste clearance, which in turn triggers a series of events including the accumulation of amyloid plaques and Tau protein tangles. Non-coding RNAs (ncRNAs), including long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), have been found to be involved in the regulation of AD. Furthermore, lncRNAs and circRNAs can act as competitive endogenous RNAs to inhibit miRNAs, and their interactions can form a complex regulatory network. Exosomes, which are extracellular vesicles (EVs), are believed to be able to transfer ncRNAs between cells, thus playing a regulatory role in the brain by crossing the blood-brain barrier (BBB). Exosomes are part of the intercellular carrier system; therefore, utilizing exosomes to deliver drugs to recipient cells might not activate the immune system, making it a potential strategy to treat central nervous system diseases. In this review, we review that AD is a multifactorial neurological disease and that ncRNAs can regulate its multiple pathogenic mechanisms to improve our understanding of the etiology of AD and to simultaneously regulate multiple pathogenic mechanisms of AD through the binding of ncRNAs to exosomes to improve the treatment of AD.

Long Non-coding RNA ANRIL and Its Role in the Development of Age-Related Diseases

ANRIL is known as a lncRNA that has many linear and circular isoforms and its polymorphisms are observed to be associated with the pathogenesis of many diseases including age-related diseases. Age-related diseases including atherosclerosis, ischemic heart disease, and Alzheimer's and Parkinson's disease are the most common cause of mortality in both developed and undeveloped countries and that is why a better understanding of their pathogenesis and underlying mechanisms is necessary for controlling their healthcare burden.In this review, we aim to gather the data of researches which have investigated the role of ANRIL in aging and its related diseases. The conclusions of this paper might give a new insight for decreasing the mortality rate of these diseases.

The Association between Long Non-Coding RNAs and Alzheimer's Disease

Neurodegeneration occurs naturally as humans age, but the presence of additional pathogenic mechanisms yields harmful and consequential effects on the brain. Alzheimer's disease (AD), the most common form of dementia, is a composite of such factors. Despite extensive research to identify the exact causes of AD, therapeutic approaches for treating the disease continue to be ineffective, indicating important gaps in our understanding of disease mechanisms. Long non-coding RNAs (lncRNAs) are an endogenous class of regulatory RNA transcripts longer than 200 nucleotides, involved in various regulatory networks, whose dysregulation is evident in several neural and extraneural diseases. LncRNAs are ubiquitously expressed across all tissues with a wide range of functions, including controlling cell differentiation and development, responding to environmental stimuli, and other physiological processes. Several lncRNAs have been identified as potential contributors in worsening neurodegeneration due to altered regulation during abnormal pathological conditions. Within neurological disease, lncRNAs are prime candidates for use as biomarkers and pharmacological targets. Gender-associated lncRNA expression is altered in a gender-dependent manner for AD, suggesting more research needs to be focused on this relationship. Overall, research on lncRNAs and their connection to neurodegenerative disease is growing exponentially, as commercial enterprises are already designing and employing RNA therapeutics. In this review we offer a comprehensive overview of the current state of knowledge on the role of lncRNAs in AD and discuss the potential implications of lncRNA as potential therapeutic targets and diagnostic biomarkers in patients with Alzheimer's disease.

Alterations of mRNAs and Non-coding RNAs Associated with Neuroinflammation in Alzheimer's Disease

Alzheimer's disease is a neurodegenerative pathology whose pathognomonic hallmarks are increased generation of β-amyloid (Aβ) peptide, production of hyperphosphorylated (pTau), and neuroinflammation. The last is an alteration closely related to the progression of AD and although it is present in multiple neurodegenerative diseases, the pathophysiological events that characterize neuroinflammatory processes vary depending on the disease. In this article, we focus on mRNA and non-coding RNA alterations as part of the pathophysiological events characteristic of neuroinflammation in AD and the influence of these alterations on the course of the disease through interaction with multiple RNAs related to the generation of Aβ, pTau, and neuroinflammation itself.

Non-Coding RNAs and Neurodegenerative Diseases: Information of their Roles in Apoptosis

Apoptosis can be known as a key factor in the pathogenesis of neurodegenerative disorders. In disease conditions, the rate of apoptosis expands and tissue damage may become apparent. Recently, the scientific studies of the non-coding RNAs (ncRNAs) has provided new information of the molecular mechanisms that contribute to neurodegenerative disorders. Numerous reports have documented that ncRNAs have important contributions to several biological processes associated with the increase of neurodegenerative disorders. In addition, microRNAs (miRNAs), circular RNAs (circRNAs), as well as, long ncRNAs (lncRNAs) represent ncRNAs subtypes with the usual dysregulation in neurodegenerative disorders. Dysregulating ncRNAs has been associated with inhibiting or stimulating apoptosis in neurodegenerative disorders. Therefore, this review highlighted several ncRNAs linked to apoptosis in neurodegenerative disorders. CircRNAs, lncRNAs, and miRNAs were also illustrated completely regarding the respective signaling pathways of apoptosis.

Exploring the Regulatory Landscape of Dementia: Insights from Non-Coding RNAs

Dementia, a multifaceted neurological syndrome characterized by cognitive decline, poses significant challenges to daily functioning. The main causes of dementia, including Alzheimer's disease (AD), frontotemporal dementia (FTD), Lewy body dementia (LBD), and vascular dementia (VD), have different symptoms and etiologies. Genetic regulators, specifically non-coding RNAs (ncRNAs) such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), are known to play important roles in dementia pathogenesis. MiRNAs, small non-coding RNAs, regulate gene expression by binding to the 3' untranslated regions of target messenger RNAs (mRNAs), while lncRNAs and circRNAs act as molecular sponges for miRNAs, thereby regulating gene expression. The emerging concept of competing endogenous RNA (ceRNA) interactions, involving lncRNAs and circRNAs as competitors for miRNA binding, has gained attention as potential biomarkers and therapeutic targets in dementia-related disorders. This review explores the regulatory roles of ncRNAs, particularly miRNAs, and the intricate dynamics of ceRNA interactions, providing insights into dementia pathogenesis and potential therapeutic avenues.

NcRNAs: A synergistically antiapoptosis therapeutic tool in Alzheimer's disease

AIMS

The aim of this review is to systematically summarize and analyze the noncoding RNAs (ncRNAs), especially microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), in the cell apoptosis among Alzheimer's disease (AD) in recent years to demonstrate their value in the diagnosis and treatment of AD.

METHODS

We systematically summarized in vitro and in vivo studies focusing on the ncRNAs in the regulation of cell apoptosis among AD in PubMed, ScienceDirect, and Google Scholar.

RESULTS

We discover three patterns of ncRNAs (including 'miRNA-mRNA', 'lncRNA-miRNA-mRNA', and 'circRNA-miRNA-mRNA') form the ncRNA-based regulatory networks in regulating cell apoptosis in AD.

CONCLUSIONS

This review provides a future diagnosis and treatment strategy for AD patients based on ncRNAs.

The Potential of Targeting Autophagy-Related Non-coding RNAs in the Treatment of Alzheimer's and Parkinson's Diseases

Clearance of accumulated protein aggregates is one of the functions of autophagy. Recently, a clearer understanding of non-coding RNAs (ncRNAs) functions documented that ncRNAs have important roles in several biological processes associated with the development and progression of neurodegenerative disorders. Subtypes of ncRNA, including microRNA (miRNA), long noncoding RNA (lncRNA), and circular RNA (circRNA), are commonly dysregulated in neurodegenerative disorders such as Alzheimer and Parkinson diseases. Dysregulation of these non-coding RNAs has been associated with inhibition or stimulation of autophagy. Decreased miR-124 led to decreased/increased autophagy in experimental model of Alzheimer and Parkinson diseases. Increased BACE1-AS showed enhanced autophagy in Alzheimer disease by targeting miR-214-3p, Beclin-1, LC3-I/LC3-II, p62, and ATG5. A significant increase in NEAT1led to stimulated autophagy in experimental model of PD by targeting PINK1, LC3-I, LC3-II, p62 and miR-374c-5p. In addition, increased BDNF-AS and SNHG1 decreased autophagy in MPTP-induced PD by targeting miR-125b-5p and miR-221/222, respectively. The upregulation of circNF1-419 and circSAMD4A resulted in an increased autophagy by regulating Dynamin-1 and miR-29c 3p, respectively. A detailed discussion of miRNAs, circRNAs, and lncRNAs in relation to their autophagy-related signaling pathways is presented in this study.

Role of long non-coding RNAs in the pathophysiology of Alzheimer's disease and other dementias

Dementia is the term used to describe a group of cognitive disorders characterized by a decline in memory, thinking, and reasoning abilities that interfere with daily life activities. Examples of dementia include Alzheimer's Disease (AD), Frontotemporal dementia (FTD), Amyotrophic lateral sclerosis (ALS), Vascular dementia (VaD) and Progressive supranuclear palsy (PSP). AD is the most common form of dementia. The hallmark pathology of AD includes formation of β-amyloid (Aβ) oligomers and tau hyperphosphorylation in the brain, which induces neuroinflammation, oxidative stress, synaptic dysfunction, and neuronal apoptosis. Emerging studies have associated long non-coding RNAs (lncRNAs) with the pathogenesis and progression of the neurodegenerative diseases. LncRNAs are defined as RNAs longer than 200 nucleotides that lack the ability to encode functional proteins. LncRNAs play crucial roles in numerous biological functions for their ability to interact with different molecules, such as proteins and microRNAs, and subsequently regulate the expression of their target genes at transcriptional and post-transcriptional levels. In this narrative review, we report the function and mechanisms of action of lncRNAs found to be deregulated in different types of dementia, with the focus on AD. Finally, we discuss the emerging role of lncRNAs as biomarkers of dementias.

MicroRNA‑203a‑3p improves bleomycin and pingyangmycin sensitivity by inactivating the PI3K/AKT pathway in hemangioma

MicroRNAs (miRs) have been found to play a fundamental role in the pathology and progression of hemangioma. Of note, miR-203a-3p prevents hemangioma progression via inactivation of the PI3K/AKT pathway. Bleomycin and pingyangmycin are drugs used in sclerotherapy, but certain hemangioma patients experience drug resistance, leading to poor clinical outcomes. The present study aimed to explore the impact of miR-203a-3p on bleomycin and pingyangmycin sensitivity in hemangioma, as well as the involvement of the PI3K/AKT pathway. miR-203a-3p or negative control mimics were transfected into human hemangioma endothelial cells, which were treated with 0-20 µM bleomycin or pingyangmycin. Subsequently, 740 Y-P, a PI3K/AKT pathway agonist, was added. Cell viability, rate of apoptosis and the expression levels of proteins involved in the PI3K/AKT pathway, including phosphorylated (p)-PI3K, PI3K, p-AKT and AKT, were detected. miR-203a-3p overexpression significantly decreased the half-maximal inhibitory concentration (IC50) values of bleomycin (5.84±0.87 vs. 14.23±2.17 µM; P<0.01) and pingyangmycin (5.13±0.55 vs. 12.04±1.86 µM; P<0.01), compared with untreated cells. In addition, under bleomycin or pingyangmycin treatment, miR-203a-3p overexpression significantly reduced the proportion of EdU positive cells (both P<0.05) and B-cell leukemia/lymphoma-2 (BCL2) protein expression levels (both P<0.05), whilst increasing cell apoptosis rate (both P<0.05) and cleaved caspase 3 protein expression levels (both P<0.05) compared with untreated controls. Furthermore, miR-203a-3p overexpression significantly inhibited the phosphorylation of PI3K and AKT (both P<0.05), an effect that was significantly diminished by 740 Y-P treatment (both P<0.01). In addition, 740 Y-P significantly increased IC50 values of bleomycin (P<0.01) and pingyangmycin (P<0.001) and also significantly increased the proportion of EdU-positive cells and BCL2 protein expression levels, while decreasing the apoptosis rate and cleaved caspase 3 protein expression levels in cells treated with bleomycin or pingyangmycin (all P<0.05). Of note, 740 Y-P weakened the effect of miR-203a-3p overexpression on the aforementioned cellular characteristics. The present study demonstrated that miR-203a-3p improved the sensitivity of cells to bleomycin and pingyangmycin treatment by inhibiting PI3K/AKT signaling in hemangioma.

ANRIL: A Long Noncoding RNA in Age-related Diseases

The intensification of the aging population is often accompanied by an increase in agerelated diseases, which impair the quality of life of the elderly. The characteristic feature of aging is progressive physiological decline, which is the largest cause of human pathology and death worldwide. However, natural aging interacts in exceptionally complex ways within and between organs, but its underlying mechanisms are still poorly understood. Long non-coding RNA (lncRNA) is a type of noncoding RNA that exceeds 200 nucleotides in length and does not possess protein-coding ability. It plays a crucial role in the occurrence and development of diseases. ANRIL, also known as CDKN2B-AS1, is an antisense ncRNA located at the INK4 site. It can play a crucial role in agerelated disease progression by regulating single nucleotide polymorphism, histone modifications, or post-transcriptional modifications (such as RNA stability and microRNA), such as cardiovascular disease, diabetes, tumor, arthritis, and osteoporosis. Therefore, a deeper understanding of the molecular mechanisms of lncRNA ANRIL in age-related diseases will help provide new diagnostic and therapeutic targets for clinical practice.

Biomaterials-based anti-inflammatory treatment strategies for Alzheimer's disease

The current therapeutic drugs for Alzheimer's disease only improve symptoms, they do not delay disease progression. Therefore, there is an urgent need for new effective drugs. The underlying pathogenic factors of Alzheimer's disease are not clear, but neuroinflammation can link various hypotheses of Alzheimer's disease; hence, targeting neuroinflammation may be a new hope for Alzheimer's disease treatment. Inhibiting inflammation can restore neuronal function, promote neuroregeneration, reduce the pathological burden of Alzheimer's disease, and improve or even reverse symptoms of Alzheimer's disease. This review focuses on the relationship between inflammation and various pathological hypotheses of Alzheimer's disease; reports the mechanisms and characteristics of small-molecule drugs (e.g., nonsteroidal anti-inflammatory drugs, neurosteroids, and plant extracts); macromolecule drugs (e.g., peptides, proteins, and gene therapeutics); and nanocarriers (e.g., lipid-based nanoparticles, polymeric nanoparticles, nanoemulsions, and inorganic nanoparticles) in the treatment of Alzheimer's disease. The review also makes recommendations for the prospective development of anti-inflammatory strategies based on nanocarriers for the treatment of Alzheimer's disease.

The Role of Non-coding RNAs in Alzheimer's Disease: Pathogenesis, Novel Biomarkers, and Potential Therapeutic Targets

Long non-coding RNAs (IncRNAs) are regulatory RNA transcripts that have recently been associated with the onset of many neurodegenerative illnesses, including Alzheimer's disease (AD). Several IncRNAs have been found to be associated with AD pathophysiology, each with a distinct mechanism. In this review, we focused on the role of IncRNAs in the pathogenesis of AD and their potential as novel biomarkers and therapeutic targets. Searching for relevant articles was done using the PubMed and Cochrane library databases. Studies had to be published in full text in English in order to be considered. Some IncRNAs were found to be upregulated, while others were downregulated. Dysregulation of IncRNAs expression may contribute to AD pathogenesis. Their effects manifest as the synthesis of beta-amyloid (Aβ) plaques increases, thereby altering neuronal plasticity, inducing inflammation, and promoting apoptosis. Despite the need for more investigations, IncRNAs could potentially increase the sensitivity of early detection of AD. Until now, there has been no effective treatment for AD. Hence, InRNAs are promising molecules and may serve as potential therapeutic targets. Although several dysregulated AD-associated lncRNAs have been discovered, the functional characterization of most lncRNAs is still lacking.

Noncoding RNAs in Alzheimer's Disease: Overview of Functional and Therapeutic Significance

Alzheimer's disease (AD) is a multifactorial disorder resulting from the complex interaction between genetic, epigenetic, and environmental factors. It represents an impending epidemic and lacks effective pharmacological interventions. The emergence of high throughput sequencing techniques and comprehensive genome evaluation has uncovered a diverse spectrum of noncoding RNA (ncRNA) families. ncRNAs are the critical modulators of an eclectic array of biological processes and are now transpiring as imperative players in diagnosing and treating various diseases, including neurodegenerative disorders. Several ncRNAs are explicitly augmented in the brain, wherein they potentially regulate cognitive abilities and other functions of the central nervous system. Growing evidence suggests the substantial role of ncRNAs as modulators of tau phosphorylation, Aβ production, neuroinflammation, and neuronal survival. It indicates their therapeutic relevance as a biomarker and druggable targets against AD. The current review summarizes the existing literature on the functional significance of ncRNAs in AD pathogenesis and its imminent implications in clinics.

Lnc-ANRIL modulates the immune response associated with NF-κB pathway in LPS-stimulated bovine mammary epithelial cells

BACKGROUND

The antisense noncoding RNA in the INK4 locus (ANRIL) has been confirmed related to multiple disease progression, but the role and exact mechanisms of lnc-ANRIL in lipopolysaccharide (LPS)-induced inflammation of bovine mammary epithelial cells (MAC-T) remain unclear.

AIMS

This manuscript focused on expounding the functional role of lnc-ANRIL through experiments performed in MAC-T.

METHODS

At the in vitro level, we established a Bovine mammary epithelial cell (BMEC) cell model of mastitis by LPS treatment. Transfection of siRNA was examined by immunofluorescence localization and RT-qPCR. CCK8, clonogenic assay and EdU were used to detect the proliferation ability of the cells. Cell cycle and apoptosis were detected by flow cytometry and Western blot. The levels of inflammatory factors and oxidative stress markers were detected by ELISA kits.

RESULTS

Cell Counting Kit-8, colony formation, and 5-ethynyl-20-deoxyuridine were adopted and the data illustrated that LPS could significantly suppress the cell proliferation, while knockdown of lnc-ANRIL expression obviously promoted MAC-T cell proliferation compared with LPS or LPS + si-NC group. Flow cytometry analysis demonstrated that lnc-ANRIL could induce MAC-T cell apoptosis. In addition, downregulation of lnc-ANRIL affected LPS-induced immune response by regulating inflammatory factor expressions and modulating the nuclear factor kappa B (NF-κB) axis in MAC-T cells.

CONCLUSION

Our results suggest that lnc-ANRIL is involved in the regulation of cell proliferation, cell cycle, and cell apoptosis of MAC-T cells, and plays an important role in the inflammatory and immune response of MAC-T cells through the regulation of the NF-κB pathway, proposing new therapeutic strategies for the treatment of innate immune response-related disease such as bovine mastitis.

Roles of Non-Coding RNA in Alzheimer's Disease Pathophysiology

Alzheimer's disease (AD) is a chronic neurodegenerative disorder that is accompanied by deficits in memory and cognitive functions. The disease is pathologically characterised by the accumulation and aggregation of an extracellular peptide referred to as amyloid-β (Aβ) in the form of amyloid plaques and the intracellular aggregation of a hyperphosphorelated protein tau in the form of neurofibrillary tangles (NFTs) that cause neuroinflammation, synaptic dysfunction, and oxidative stress. The search for pathomechanisms leading to disease onset and progression has identified many key players that include genetic, epigenetic, behavioural, and environmental factors, which lend support to the fact that this is a multi-faceted disease where failure in various systems contributes to disease onset and progression. Although the vast majority of individuals present with the sporadic (non-genetic) form of the disease, dysfunctions in numerous protein-coding and non-coding genes have been implicated in mechanisms contributing to the disease. Recent studies have provided strong evidence for the association of non-coding RNAs (ncRNAs) with AD. In this review, we highlight the current findings on changes observed in circular RNA (circRNA), microRNA (miRNA), short interfering RNA (siRNA), piwi-interacting RNA (piRNA), and long non-coding RNA (lncRNA) in AD. Variations in these ncRNAs could potentially serve as biomarkers or therapeutic targets for the diagnosis and treatment of Alzheimer's disease. We also discuss the results of studies that have targeted these ncRNAs in cellular and animal models of AD with a view for translating these findings into therapies for Alzheimer's disease.

Urinary Cytokines as Potential Biomarkers of Mild Cognitive Impairment and Alzheimer's Disease: A Pilot Study

Background

Alzheimer's disease (AD) is the most common form of dementia, accounting for 80% of all cases. Mild cognitive impairment (MCI) is a transitional state between normal aging and AD. Early detection is crucial, as irreversible brain damage occurs before symptoms manifest.

Objective

This study aimed to identify potential biomarkers for early detection of AD by analyzing urinary cytokine concentrations. We investigated 37 cytokines in AD, MCI, and cognitively normal individuals (NC), assessing their associations with AD development.

Methods

Urinary cytokine concentrations were measured in AD (n = 25), MCI (n = 25), and NC (n = 26) patients. IL6ST and MMP-2 levels were compared between AD and NC, while TNFRSF8, IL6ST, and IL-19 were assessed in AD versus MCI. Diagnostic models distinguished AD from NC, and in-silico analysis explored molecular mechanisms related to AD.

Results

Significant perturbations in IL6ST and MMP-2 concentrations were observed in AD urine compared to NC, suggesting their potential as biomarkers. TNFRSF8, IL6ST, and IL-19 differed significantly between AD and MCI, implicating them in disease progression. Diagnostic models exhibited promising performance (AUC: 0.59-0.79, sensitivity: 0.72-0.80, specificity: 0.56-0.78) in distinguishing AD from NC. In-silico analysis revealed molecular insights, including relevant non-coding RNAs, microRNAs, and transcription factors.

Conclusion

This study establishes significant associations between urinary cytokine concentrations and AD and MCI. IL6ST, MMP-2, TNFRSF8, IL6ST, and IL-19 emerge as potential biomarkers for early detection of AD. In-silico analysis enhances understanding of molecular mechanisms in AD. Further validation and exploration of these biomarkers in larger cohorts are warranted to assess their clinical utility.

The Emerging Role of Autophagy-Associated lncRNAs in the Pathogenesis of Neurodegenerative Diseases

Neurodegenerative diseases (NDDs) have become a significant global public health problem and a major societal burden. The World Health Organization predicts that NDDs will overtake cancer as the second most common cause of human mortality within 20 years. Thus, it is urgently important to identify pathogenic and diagnostic molecular markers related to neurodegenerative processes. Autophagy is a powerful process for removing aggregate-prone proteins in neurons; defects in autophagy are often associated with the pathogenesis of NDDs. Long non-coding RNAs (lncRNAs) have been suggested as key regulators in neurodevelopment; aberrant regulation of lncRNAs contributes to neurological disorders. In this review, we summarize the recent progress in the study of lncRNAs and autophagy in the context of neurodegenerative disorders, especially Alzheimer's disease (AD) and Parkinson's disease (PD). The information presented here should provide guidance for future in-depth investigations of neurodegenerative processes and related diagnostic molecular markers and treatment targets.

Targeting Novel microRNAs in Developing Novel Alzheimer's Disease Treatments

Alzheimer's disease (AD) is considered a multifactorial disease and a significant cause of dementia during aging. This neurodegenerative disease process is classically divided into two different pathologies cerebral accumulation of amyloid-β and hyperphosphorylated neurofibrillary tau tangles. In recent years, massive efforts have been made to treat AD by decreasing amyloid-β and tau in the brains of patients with AD, with no success. The dysfunction of a wide range of microRNAs promotes the generation and insufficient clearance of amyloid-β (Aβ) and increases tau plaques which are the pathophysiological markers of AD. Disturbance of these microRNAs is associated with mitochondrial dysfunction, oxidative damage, inflammation, apolipoprotein E4 (APOE4) pathogenic process, synaptic loss, and cognitive deficits induced by AD. Targeting a specific microRNA to restore AD-induced impairments at multiple stages might provide a promising approach for developing new drugs and therapeutic strategies for patients with AD. This review focuses on different mechanisms of microRNAs in AD pathophysiology.

ANRIL overexpression globally induces expression and alternative splicing of genes involved in inflammation in HUVECs

Long non‑coding (lnc)RNAs serve important cellular functions and certain lncRNAs have roles in different mechanisms of gene regulation. lncRNA‑antisense non‑coding RNA in the INK4 locus (ANRIL) affects cell inflammation; however, the potential genes underlying the inflammatory response regulated by ANRIL remain unclear. In the present study, the potential function of ANRIL in regulating gene expression and alternative splicing was assessed. ANRIL‑regulated human umbilical vein endothelial cell (HUVEC) transcriptome was obtained using high‑throughput RNA sequencing (RNA‑seq) to evaluate the potential role of ANRIL. Following plasmid transfection, gene expression profile and alternative splicing pattern of HUVECs overexpressing ANRIL were analyzed using RNA‑seq. ANRIL overexpression affected the transcription levels of genes associated with the inflammatory response, NF‑κB signaling pathway, type I interferon‑mediated signal transduction pathway and innate immune response. ANRIL regulated the alternative splicing of hundreds of genes with functions such as gene expression, translation, DNA repair, RNA processing and participation in the NF‑κB signaling pathway. Many of these genes serve a key role in the inflammatory response. ANRIL‑regulated inflammatory response may be achieved by regulating alternate splicing and transcription. The present study broadened the understanding of ANRIL‑mediated gene regulation mechanisms and clarified the role of ANRIL in mediating inflammatory response mechanisms.

New Insights into lncRNAs in Aβ Cascade Hypothesis of Alzheimer's Disease

Alzheimer's disease (AD) is the most common type of dementia, but its pathogenesis is not fully understood, and effective drugs to treat or reverse the progression of the disease are lacking. Long noncoding RNAs (lncRNAs) are abnormally expressed and deregulated in AD and are closely related to the occurrence and development of AD. In addition, the high tissue specificity and spatiotemporal specificity make lncRNAs particularly attractive as diagnostic biomarkers and specific therapeutic targets. Therefore, an in-depth understanding of the regulatory mechanisms of lncRNAs in AD is essential for developing new treatment strategies. In this review, we discuss the unique regulatory functions of lncRNAs in AD, ranging from Aβ production to clearance, with a focus on their interaction with critical molecules. Additionally, we highlight the advantages and challenges of using lncRNAs as biomarkers for diagnosis or therapeutic targets in AD and present future perspectives in clinical practice.

Long Non-Coding RNAs, Extracellular Vesicles and Inflammation in Alzheimer's Disease

Alzheimer's Disease (AD) has currently no effective treatment; however, preventive measures have the potential to reduce AD risk. Thus, accurate and early prediction of risk is an important strategy to alleviate the AD burden. Neuroinflammation is a major factor prompting the onset of the disease. Inflammation exerts its toxic effect via multiple mechanisms. Amongst others, it is affecting gene expression via modulation of non-coding RNAs (ncRNAs), such as miRNAs. Recent evidence supports that inflammation can also affect long non-coding RNA (lncRNA) expression. While the association between miRNAs and inflammation in AD has been studied, the role of lncRNAs in neurodegenerative diseases has been less explored. In this review, we focus on lncRNAs and inflammation in the context of AD. Furthermore, since plasma-isolated extracellular vesicles (EVs) are increasingly recognized as an effective monitoring strategy for brain pathologies, we have focused on the studies reporting dysregulated lncRNAs in EVs isolated from AD patients and controls. The revised literature shows a positive association between pro-inflammatory lncRNAs and AD. However, the reports evaluating lncRNA alterations in EVs isolated from the plasma of patients and controls, although still limited, confirm the value of specific lncRNAs associated with AD as reliable biomarkers. This is an emerging field that will open new avenues to improve risk prediction and patient stratification, and may lead to the discovery of potential novel therapeutic targets for AD.

Non-coding RNAs: The Neuroinflammatory Regulators in Neurodegenerative Diseases

As a common indication of nervous system diseases, neuroinflammation has attracted more and more attention, especially in the process of a variety of neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. Two types of non-coding RNAs (ncRNAs) are widely involved in the process of neuroinflammation in neurodegenerative diseases, namely long non-coding RNAs (lncRNAs) and microRNAs (miRNAs). However, no research has systematically summarized that lncRNAs and miRNAs regulate neurodegenerative diseases through neuroinflammatory mechanisms. In this study, we summarize four main mechanisms of lncRNAs and miRNAs involved in neuroinflammation in neurodegenerative diseases, including the imbalance between proinflammatory and neuroprotective cells in microglia and astrocytes, NLRP3 inflammasome, oxidative stress, and mitochondrial dysfunction, and inflammatory mediators. We hope to clarify the regulatory mechanism of lncRNAs and miRNAs in neurodegenerative diseases and provide new insights into the etiological treatment of neurodegenerative diseases from the perspective of neuroinflammation.

Non-Coding RNAs as Novel Regulators of Neuroinflammation in Alzheimer's Disease

Alzheimer’s disease (AD) is one of the most common causes of dementia. Although significant breakthroughs have been made in understanding the progression and pathogenesis of AD, it remains a worldwide problem and a significant public health burden. Thus, more efficient diagnostic and therapeutic strategies are urgently required. The latest research studies have revealed that neuroinflammation is crucial in the pathogenesis of AD. Non-coding RNAs (ncRNAs), including long noncoding RNAs (lncRNAs), microRNAs (miRNAs), circular RNAs (circRNAs), PIWI-interacting RNAs (piRNAs), and transfer RNA-derived small RNAs (tsRNAs), have been strongly associated with AD-induced neuroinflammation. Furthermore, several ongoing pre-clinical studies are currently investigating ncRNA as disease biomarkers and therapeutic interventions to provide new perspectives for AD diagnosis and treatment. In this review, the role of different types of ncRNAs in neuroinflammation during AD are summarized in order to improve our understanding of AD etiology and aid in the translation of basic research into clinical practice.

The Role of the Microbiota-Gut-Brain Axis in the Development of Alzheimer's Disease

Along with the increase in life expectancy in the populations of developed and developing countries resulting from better access and improved health care, the number of patients with dementia, including Alzheimer’s disease (AD), is growing. The disease was first diagnosed and described at the beginning of the 20th century. However, to this day, there is no effective causal therapy, and symptomatic treatment often improves patients’ quality of life only for a short time. The current pharmacological therapies are based mainly on the oldest hypotheses of the disease—cholinergic (drugs affecting the cholinergic system are available), the hypothesis of amyloid-β aggregation (an anti-amyloid drug was conditionally approved by the FDA in 2020), and one drug is an N-methyl-D-aspartate receptor (NMDAR) antagonist (memantine). Hypotheses about AD pathogenesis focus on the nervous system and the brain. As research progresses, it has become known that AD can be caused by diseases that have been experienced over the course of a lifetime, which could also affect other organs. In this review, we focus on the potential association of AD with the digestive system, primarily the gut microbiota. The role of diet quality in preventing and alleviating Alzheimer’s disease is also discussed. The problem of neuroinflammation, which may be the result of microbiota disorders, is also described. An important aspect of the work is the chapter on the treatment strategies for changing the microbiota, potentially protecting against the disease and alleviating its course in the initial stages.

Transcriptome analysis of fasudil treatment in the APPswe/PSEN1dE9 transgenic (APP/PS1) mice model of Alzheimer's disease

Alzheimer's disease (AD) is the most common cause of progressive dementia. In the present study, we showed hippocampal tissue transcriptome analysis in APPswe/PSEN1dE9 (APP/PS1, AD model) mice treated with fasudil (ADF) and compared with AD mice treated with saline (ADNS) and wild type mice (WT). The competing endogenous RNA (ceRNA) network was constructed and validated the differential expression of mRNA, lncRNA, miRNA, and circRNA. Our study showed differentially expressed mRNAs (DEMs) between WT and ADNS, while enriched in cell growth and death and nervous system pathways. DEMs between ADNS-ADF were enriched in the nervous system, glycosaminoglycan biosynthesis-keratan sulfate (KS) and Quorum sensing pathways. We validated four genes with RT-PCR, whereas enrichment of Acyl-CoA Synthetase Long Chain Family Member 4 (Acsl4, ENSMUST00000112903) in Quorum sensing pathways, and BTG anti-proliferation factor 1 (Btg1, ENSMUST00000038377) in RNA degradation pathways were conducted. Expression of these two genes were higher in ADNS, but were significantly reduced in ADF. Histone H4 transcription factor (Hinfp, ENSMUST00000216508) orchestrate G1/S transition of mitotic cell cycle and co-expressed with mmu-miR-26a-2-3p-mediated ceRNA and mmu-miR-3065-5p-mediated ceRNA; Wnt family member 4 (Wnt4, ENSMUST00000045747) was enriched in mTOR, Hippo and Wnt signaling pathway. Expression of these two genes were significantly lower in ADNS, and fasudil treatment reverse it. The present studies demonstrated four genes: Acsl4, Btg1, Hinfp, Wnt4 could be potential biomarkers of AD and the targets of fasudil treatment. These results will pave a novel direction for future clinic studies for AD and fasudil treatment.

An Unanticipated Modulation of Cyclin-Dependent Kinase Inhibitors: The Role of Long Non-Coding RNAs

It is now definitively established that a large part of the human genome is transcribed. However, only a scarce percentage of the transcriptome (about 1.2%) consists of RNAs that are translated into proteins, while the large majority of transcripts include a variety of RNA families with different dimensions and functions. Within this heterogeneous RNA world, a significant fraction consists of sequences with a length of more than 200 bases that form the so-called long non-coding RNA family. The functions of long non-coding RNAs range from the regulation of gene transcription to the changes in DNA topology and nucleosome modification and structural organization, to paraspeckle formation and cellular organelles maturation. This review is focused on the role of long non-coding RNAs as regulators of cyclin-dependent kinase inhibitors’ (CDKIs) levels and activities. Cyclin-dependent kinases are enzymes necessary for the tuned progression of the cell division cycle. The control of their activity takes place at various levels. Among these, interaction with CDKIs is a vital mechanism. Through CDKI modulation, long non-coding RNAs implement control over cellular physiology and are associated with numerous pathologies. However, although there are robust data in the literature, the role of long non-coding RNAs in the modulation of CDKIs appears to still be underestimated, as well as their importance in cell proliferation control.

Long Non-coding RNA: Insight Into Mechanisms of Alzheimer's Disease

Alzheimer's disease (AD), a heterogeneous neurodegenerative disorder, is the most common cause of dementia accounting for an estimated 60–80% of cases. The pathogenesis of AD remains unclear, and no curative treatment is available so far. Increasing evidence has revealed a vital role of non-coding RNAs (ncRNAs), especially long non-coding RNAs (lncRNAs), in AD. LncRNAs contribute to the pathogenesis of AD via modulating amyloid production, Tau hyperphosphorylation, mitochondrial dysfunction, oxidative stress, synaptic impairment and neuroinflammation. This review describes the biological functions and mechanisms of lncRNAs in AD, indicating that lncRNAs may provide potential therapeutic targets for the diagnosis and treatment of AD.

Long non-coding RNA ANRIL interacts with microRNA-34a and microRNA-125a, and they all correlate with disease risk and severity of Parkinson's disease

BACKGROUND

This study aimed to investigate the correlation of long non-coding RNA antisense non-coding RNA in the INK4 locus (lncRNA ANRIL) and its target microRNAs (microRNA-34a (miR-34a) and microRNA-125a (miR-125a)) with disease risk and severity of Parkinson's disease (PD).

METHODS

Seventy-eight PD patients and 78 age-/gender-matched controls were consecutively enrolled. Their peripheral blood mononuclear cell samples were collected and proposed for the reverse-transcription quantitative polymerase chain reaction to complete lncRNA ANRIL, miR-34a, and miR-125a measurements.

RESULTS

LncRNA ANRIL was upregulated, while miR-34a and miR-125a were downregulated in PD patients compared to controls (all p < 0.001). Further, they all showed certain values for PD risk identification by ROC curve analyses, among which lncRNA ANRIL showed the highest AUC (AUC: 0.879, 95% CI: 0.824-0.934). Furthermore, lncRNA ANRIL negatively correlated with miR-34a (p = 0.016) and miR-125a (p = 0.005) in PD patients, but not in controls. In addition, lncRNA ANRIL was observed to positively associate with UPDRS-I score (p = 0.029), UPDRS-III score (p = 0.006), and UPDRS-IV score (p = 0.033), while negatively correlated with MMSE score (p = 0.003). These associations were less distinct as to miR-34a and miR-125a.

CONCLUSION

LncRNA ANRIL interacts with miR-34a and miR-125a in PD patients, and they all correlate with disease risk and severity of PD.

Administration of miR-195 Inhibitor Enhances Memory Function Through Improving Synaptic Degradation and Mitochondrial Dysfunction of the Hippocampal Neurons in SAMP8 Mice

BACKGROUND

Mitochondrial dysfunction is an early feature of Alzheimer's disease (AD) and miR-195 is involved in mitochondrial disorder through targeting MFN-2 protein in hippocampal neurons of AD.

OBJECTIVE

To clarify if administration of miR-195 inhibitor could enhance the memory deficits through improving hippocampal neuron mitochondrial dysfunction in SAMP8 mice.

METHODS

The expression of miR-195 was detected by RT-qPCR in primary hippocampal neurons and HT-22 cells treated with Aβ 1-42. Morris water maze (MWM) was used to assess the learning and memory function in SAMP8 mice administrated with antagomir-195. Transmission electron microscopy was employed to determine the morphological changes of synapses and mitochondria of hippocampus in SAMP8 mice. Mitochondrial respiration was measured using a high-resolution oxygraph.

RESULTS

The expression of miR-195 were upregulated in the primary hippocampal neurons and HT-22 cells induced by Aβ 1-42. Inhibition of miR-195 ameliorated the mitochondrial dysfunction in HT-22 cells induced by Aβ 1-42, including mitochondrial morphologic damages, mitochondrial membrane potential, respiration function, and ATP production. Administration of antagomir-195 by the third ventricle injection markedly ameliorated the cognitive function, postsynaptic density thickness, length of synaptic active area, mitochondrial aspect ratio, and area in hippocampus of SAMP8 mice. Finally, antagomir-195 was able to promote an increase in the activity of respiratory chain complex CI and II in SAMP8 mice.

CONCLUSION

This study demonstrated that miR-195 inhibitor ameliorated the cognitive impairment of AD mice by improving mitochondrial structure damages and dysfunction in the hippocampal neurons, which provide an experimental basis for further exploring the treatment strategy of AD.

Roles and functions of antisense lncRNA in vascular aging

Vascular aging is a major cause of morbidity and mortality in the elderly population. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), forming the intima and media layers of the vessel wall respectively, are closely associated with the process of vascular aging and vascular aging-related diseases. Numerous studies have revealed the pathophysiologic mechanism through which lncRNA contributes to vascular aging, hence more attention is now paid to the role played by antisense long non-coding RNA (AS-lncRNA) in the pathogenesis of vascular aging. Nonetheless, only a small number of studies focus on the specific mechanism through which AS-lncRNA mediates vascular aging. In this review, we summarize the roles and functions of AS-lncRNA with regards to the development of vascular aging and vascular aging-related disease. We also aim to deepen our understanding of this process and provide alternative therapeutic modalities for vascular aging-related diseases.

Molecular Insight Into the Therapeutic Potential of Long Non-coding RNA-Associated Competing Endogenous RNA Axes in Alzheimer's Disease: A Systematic Scoping Review

Alzheimer's disease (AD) is a heterogeneous degenerative brain disorder with a rising prevalence worldwide. The two hallmarks that characterize the AD pathophysiology are amyloid plaques, generated via aggregated amyloid β, and neurofibrillary tangle, generated via accumulated phosphorylated tau. At the post-transcriptional and transcriptional levels, the regulatory functions of non-coding RNAs, in particular long non-coding RNAs (lncRNAs), have been ascertained in gene expressions. It is noteworthy that a number of lncRNAs feature a prevalent role in their potential of regulating gene expression through modulation of microRNAs via a process called the mechanism of competing endogenous RNA (ceRNA). Given the multifactorial nature of ceRNA interaction networks, they might be advantageous in complex disorders (e.g., AD) investigations at the therapeutic targets level. We carried out scoping review in this research to analyze validated loops of ceRNA in AD and focus on ceRNA axes associated with lncRNA. This scoping review was performed according to a six-stage methodology structure and PRISMA guideline. A systematic search of seven databases was conducted to find eligible articles prior to July 2021. Two reviewers independently performed publications screening and data extraction, and quantitative and qualitative analyses were conducted. Fourteen articles were identified that fulfill the inclusion criteria. Studies with different designs reported nine lncRNAs that were experimentally validated to act as ceRNA in AD in human-related studies, including BACE1-AS, SNHG1, RPPH1, NEAT1, LINC00094, SOX21-AS1, LINC00507, MAGI2-AS3, and LINC01311. The BACE1-AS/BACE1 was the most frequent ceRNA pair. Among miRNAs, miR-107 played a key role by regulating three different loops. Understanding the various aspects of this regulatory mechanism can help elucidate the unknown etiology of AD and provide new molecular targets for use in therapeutic and clinical applications.

Gene regulation by antisense transcription: A focus on neurological and cancer diseases

Advances in high-throughput sequencing over the past decades have led to the identification of thousands of non-coding RNAs (ncRNAs), which play a major role in regulating gene expression. One emerging class of ncRNAs is the natural antisense transcripts (NATs), the RNA molecules transcribed from the opposite strand of a protein-coding gene locus. NATs are known to concordantly and discordantly regulate gene expression in both cis and trans manners at the transcriptional, post-transcriptional, translational, and epigenetic levels. Aberrant expression of NATs can therefore cause dysregulation in many biological pathways and has been observed in many genetic diseases. This review outlines the involvements and mechanisms of NATs in the pathogenesis of various diseases, with a special emphasis on neurodegenerative diseases and cancer. We also summarize recent findings on NAT knockdown and/or overexpression experiments and discuss the potential of NATs as promising targets for future gene therapies.

The emerging role of noncoding RNAs in neuroinflammation: Implications in pathogenesis and therapeutic approaches

Noncoding RNAs (ncRNAs) are important regulators of gene expression in different cell processes. Due to their ability in monitoring neural development genes, these transcripts confer neurons with the potential to exert broad control over the expression of genes for performing neurobiological functions. Although the change of ncRNA expression in different neurodegenerative diseases has been reviewed elsewhere, only recent evidence drove our attention to unravel the involvement of these molecules in neuroinflammation within these devastating disorders. Remarkably, the interactions between ncRNAs and inflammatory pathways are not fully recognized. Therefore, this review has focused on the interplay between diverse inflammatory pathways and the related ncRNAs, including microRNAs, long noncoding RNAs, and competing endogenous RNAs in Alzheimer's disease, Parkinson's diseases, amyotrophic lateral sclerosis, epilepsy, multiple sclerosis, Huntington's disease, and prion diseases. Providing novel insights in the field of combining biomarkers is a critical step for using them as diagnostic tools and therapeutic targets in clinical settings.

Knockdown of lncRNA C5orf66-AS1 inhibits osteosarcoma cell proliferation and invasion via miR-149-5p upregulation

Osteosarcoma (OS) is the most common primary malignant bone tumor in the pediatric age group. Despite the various potential treatments for OS, the cure rate of patients with OS remains very low. An increasing number of long non-coding RNAs (lncRNAs) have been identified as key regulators of the progression of malignant human tumors. However, the biological functions of the lncRNA C5orf66-antisense 1 (C5orf66-AS1) in OS are yet to be fully elucidated. The present study aimed to investigate the functions and underlying mechanisms of C5orf66-AS1 in OS tissues and cell lines. Expression levels of C5orf66-AS1 and microRNA (miRNA/miR)-149-5p in tissues from patients with OS and OS cells lines were evaluated using reverse transcription quantitative (RT-q)PCR. The miRNA target interaction between C5orf66-AS1 and miR-149-5p was predicted and verified using StarBase and dual-luciferase reporter assays. Cell viability, migration, invasion and apoptosis were analyzed using Cell Counting Kit-8, Transwell assays and flow cytometry, respectively. In addition, the expression levels of migration- and apoptosis-associated proteins [matrix metalloproteinase-9 (MMP-9), Bcl-2 and Bax] were determined using western blotting and RT-qPCR. The results demonstrated that C5orf66-AS1 was significantly upregulated and miR-149-5p was significantly downregulated in OS tissues and cells (MG63 and U2OS). Bioinformatics analysis further confirmed that miR-149-5p could directly bind to C5orf66-AS1. Furthermore, it was revealed that C5orf66-AS1 negatively regulated the expression of miR-149-5p in OS cells, as confirmed by the inhibition of C5orf66-AS1 expression and miR-149-5p upregulation in cells transfected with small interfering (si RNA targeting C5orf66-AS1. In addition, C5orf66-AS1 silencing significantly inhibited the proliferation, invasion and migration of U2OS cells, and stimulated cell apoptosis. These findings were reversed using miR-149-5p inhibitor. Increased Bax expression and decreased Bcl-2 and MMP-9 expression were also observed in C5orf66-AS1-siRNA transfected U2OS cells, compared with the control group. In summary, the results from the present study indicated that C5orf66-AS1 knockdown inhibits OS cell proliferation and invasion via the upregulation of miR-149-5p. This findings may provide a promising novel target for the treatment of OS.

The Perspective of Dysregulated LncRNAs in Alzheimer's Disease: A Systematic Scoping Review

LncRNAs act as part of non-coding RNAs at high levels of complex and stimulatory configurations in basic molecular mechanisms. Their extensive regulatory activity in the CNS continues on a small scale, from the functions of synapses to large-scale neurodevelopment and cognitive functions, aging, and can be seen in both health and disease situations. One of the vast consequences of the pathological role of dysregulated lncRNAs in the CNS due to their role in a network of regulatory pathways can be manifested in Alzheimer's as a neurodegenerative disease. The disease is characterized by two main hallmarks: amyloid plaques due to the accumulation of β-amyloid components and neurofibrillary tangles (NFT) resulting from the accumulation of phosphorylated tau. Numerous studies in humans, animal models, and various cell lines have revealed the role of lncRNAs in the pathogenesis of Alzheimer's disease. This scoping review was performed with a six-step strategy and based on the Prisma guideline by systematically searching the publications of seven databases. Out of 1,591 records, 69 articles were utterly aligned with the specified inclusion criteria and were summarized in the relevant table. Most of the studies were devoted to BACE1-AS, NEAT1, MALAT1, and SNHG1 lncRNAs, respectively, and about one-third of the studies investigated a unique lncRNA. About 56% of the studies reported up-regulation, and 7% reported down-regulation of lncRNAs expressions. Overall, this study was conducted to investigate the association between lncRNAs and Alzheimer's disease to make a reputable source for further studies and find more molecular therapeutic goals for this disease.

Long Noncoding RNAs in Neurodegenerative Diseases: Pathogenesis and Potential Implications as Clinical Biomarkers

Neurodegenerative diseases (NDDs), including Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD), and amyotrophic lateral sclerosis (ALS), are progressive and ultimately fatal. NDD onset is influenced by several factors including heredity and environmental cues. Long noncoding RNAs (lncRNAs) are a class of noncoding RNA molecules with: (i) lengths greater than 200 nucleotides, (ii) diverse biological functions, and (iii) highly conserved structures. They directly interact with molecules such as proteins and microRNAs and subsequently regulate the expression of their targets at the genetic, transcriptional, and post-transcriptional levels. Emerging studies indicate the important roles of lncRNAs in the progression of neurological diseases including NDDs. Additionally, improvements in detection technologies have enabled quantitative lncRNA detection and application to circulating fluids in clinical settings. Here, we review current research on lncRNAs in animal models and patients with NDDs. We also discuss the potential applicability of circulating lncRNAs as biomarkers in NDD diagnostics and prognostics. In the future, a better understanding of the roles of lncRNAs in NDDs will be essential to exploit these new therapeutic targets and improve noninvasive diagnostic methods for diseases.

Expression of Linear and Circular lncRNAs in Alzheimer's Disease

Alzheimer's disease is a neurodegenerative disorder of the elderly described by progressive cognitive debility. Recent studies have displayed the significance of linear and circular long non-coding RNAs (lncRNAs) in the pathobiology of Alzheimer's disease. These studies have reported the downregulation of MALAT1, while the upregulation of NEAT1, RP11-543N12.1, SOX21-AS1, BDNF-AS, BACE1-AS, ANRIL, XIST, and some other linear lncRNAs in clinical samples are obtained from these patients or animal models of Alzheimer's disease. A number of circRNAs such as ciRS-7, ciRS-7, circNF1-419, circHDAC9, circ_0000950,and circAβ-a have been shown to partake in the pathogenesis of this disorder. In the present manuscript, we provide a review of the impact of linear and circular lncRNAs in the pathobiology of Alzheimer's disease and their potential application as markers for this neurodegenerative condition.

Ginsenosides attenuate bioenergetics and morphology of mitochondria in cultured PC12 cells under the insult of amyloid beta-peptide

BACKGROUND

Mitochondrial dysfunction is one of the significant reasons for Alzheimer's disease (AD). Ginsenosides, natural molecules extracted from Panax ginseng, have been demonstrated to exert essential neuroprotective functions, which can ascribe to its anti-oxidative effect, enhancing central metabolism and improving mitochondrial function. However, a comprehensive analysis of cellular mitochondrial bioenergetics after ginsenoside treatment under Aβ-oxidative stress is missing.

METHODS

The antioxidant activities of ginsenoside Rb1, Rd, Re, Rg1 were compared by measuring the cell survival and reactive oxygen species (ROS) formation. Next, the protective effects of ginsenosides of mitochondrial bioenergetics were examined by measuring oxygen consumption rate (OCR) in PC12 cells under Aβ-oxidative stress with an extracellular flux analyzer. Meanwhile, mitochondrial membrane potential (MMP) and mitochondrial dynamics were evaluated by confocal laser scanning microscopy.

RESULTS

Ginsenoside Rg1 possessed the strongest anti-oxidative property, and which therefore provided the best protective function to PC12 cells under the Aβ oxidative stress by increasing ATP production to 3 folds, spare capacity to 2 folds, maximal respiration to 2 folds and non-mitochondrial respiration to 1.5 folds, as compared to Aβ cell model. Furthermore, ginsenoside Rg1 enhanced MMP and mitochondrial interconnectivity, and simultaneously reduced mitochondrial circularity.

CONCLUSION

In the present study, these results demonstrated that ginsenoside Rg1 could be the best natural compound, as compared with other ginsenosides, by modulating the OCR of cultured PC12 cells during oxidative phosphorylation, in regulating MMP and in improving mitochondria dynamics under Aβ-induced oxidative stress.

Long non-coding RNA: An underlying bridge linking neuroinflammation and central nervous system diseases

Central nervous system (CNS) diseases are responsible for a large proportion of morbidity and mortality worldwide. CNS diseases caused by intrinsic and extrinsic stimuli stimulate the resident immune cells including microglia and astrocyte, resulting in neuroinflammation that exacerbates the progression of diseases. Recent evidence reveals the aberrant expression patterns of long non-coding RNAs (lncRNAs) in the damaged tissues following CNS diseases. It was also proposed that lncRNAs possessed immune-modulatory activities by directly or indirectly affecting various effector proteins including transcriptional factor, acetylase, protein kinase, phosphatase, etc. In addition, lncRNAs can form a sophisticated network by interacting with other molecules to regulate the expression or activation of downstream immune response pathways. However, the major roles of lncRNAs in CNS pathophysiologies are still elusive, especially in neuroinflammation. Herein, we tend to review some potential roles of lncRNAs in modulating neuroinflammation based on current evidence in various CNS diseases, in order to provide novel explanations for the initiation and progression of CNS diseases and help to establish therapeutic strategies targeting neuroinflammation.

Interplay of RNA-Binding Proteins and microRNAs in Neurodegenerative Diseases

The number of patients with neurodegenerative diseases (NDs) is increasing, along with the growing number of older adults. This escalation threatens to create a medical and social crisis. NDs include a large spectrum of heterogeneous and multifactorial pathologies, such as amyotrophic lateral sclerosis, frontotemporal dementia, Alzheimer’s disease, Parkinson’s disease, Huntington’s disease and multiple system atrophy, and the formation of inclusion bodies resulting from protein misfolding and aggregation is a hallmark of these disorders. The proteinaceous components of the pathological inclusions include several RNA-binding proteins (RBPs), which play important roles in splicing, stability, transcription and translation. In addition, RBPs were shown to play a critical role in regulating miRNA biogenesis and metabolism. The dysfunction of both RBPs and miRNAs is often observed in several NDs. Thus, the data about the interplay among RBPs and miRNAs and their cooperation in brain functions would be important to know for better understanding NDs and the development of effective therapeutics. In this review, we focused on the connection between miRNAs, RBPs and neurodegenerative diseases.

In silico Analysis of Polymorphisms in microRNAs Deregulated in Alzheimer Disease

BACKGROUND

Alzheimer's disease (AD) is a degenerative condition characterized by progressive cognitive impairment and dementia. Findings have revolutionized current knowledge of miRNA in the neurological conditions. Two regulatory mechanisms determine the level of mature miRNA expression; one is miRNA precursor processing, and the other is gene expression regulation by transcription factors. This study is allocated to the in-silico investigation of miRNA's SNPs and their effect on other cell mechanisms.

METHODS

We used databases which annotate the functional effect of SNPs on mRNA-miRNA and miRNA-RBP interaction. Also, we investigated SNPs which are located on the promoter or UTR region.

RESULTS

miRNA SNP3.0 database indicated several SNPs in miR-339 and miR-34a in the upstream and downstream of pre-miRNA and mature miRNAs. While, for some miRNAs miR-124, and miR-125, no polymorphism was observed, and also miR-101 with ΔG -3.1 and mir-328 with ΔG 5.8 had the highest and lowest potencies to produce mature microRNA. SNP2TFBS web-server presented several SNPs which altered the Transcription Factor Binding Sites (TFBS) or generated novel TFBS in the promoter regions of related miRNA. At last, RBP-Var database provided a list of SNPs which alter miRNA-RBP interaction pattern and can also influence other miRNAs' expression.

DISCUSSION

The results indicated that SNPs microRNA affects both miRNA function and miRNA expression. Our study expands molecular insight into how SNPs in different parts of miRNA, including the regulatory (promoter), the precursor (pre-miRNA), functional regions (seed region of mature miRNA), and RBP-binding motifs, which theoretically may be correlated to the Alzheimer's disease.

The Expanding Regulatory Mechanisms and Cellular Functions of Long Non-coding RNAs (lncRNAs) in Neuroinflammation

LncRNAs have emerged as important regulatory molecules in biological processes. They serve as regulators of gene expression pathways through interactions with proteins, RNA, and DNA. LncRNA expression is altered in several diseases of the central nervous system (CNS), such as neurodegenerative disorders, stroke, trauma, and infection. More recently, it has become clear that lncRNAs contribute to regulating both pro-inflammatory and anti-inflammatory pathways in the CNS. In this review, we discuss the molecular pathways involved in the expression of lncRNAs, their role and mechanism of action during gene regulation, cellular functions, and use of lncRNAs as therapeutic targets during neuroinflammation in CNS disorders.

Knockdown of lncRNA ANRIL suppresses the production of inflammatory cytokines and mucin 5AC in nasal epithelial cells via the miR-15a-5p/JAK2 axis

The incidence of allergic rhinitis (AR) is increasing worldwide. Human nasal epithelial cells (HNECs) are the key cells in the occurrence of AR. Antisense non-coding RNA in the INK4 locus (ANRIL) was discovered to be involved in the progression of AR. However, the mechanism by which ANRIL mediates the progression of AR remains to be determined. The present study aimed to further explore the mechanism by which ANRIL regulates AR. Thereby, HNECs were treated with IL-13 to mimic AR in vitro. The mRNA expression levels of ANRIL, microRNA (miR)-15a-5p, JAK2, mucin 5AC (MUC5AC), granulocyte-macrophage colony-stimulating factor (GM-CSF) and eotaxin-1, and protein expression levels of JAK2, STAT3 and phosphorylated-STAT3 in HNECs were analyzed using reverse transcription-quantitative PCR and western blotting, respectively. ELISAs were used to detect the secretory levels of inflammatory cytokines and mucin in cell supernatants. In addition, a dual luciferase reporter assay was used to confirm the downstream target of ANRIL and the target gene of miR-15a-5p. The results revealed that the secretory levels of eotaxin-1, GM-CSF and MUC5AC were significantly upregulated by IL-13 in the supernatant of HNECs. The expression levels of ANRIL and JAK2 were also upregulated in IL-13-induced HNECs, while the expression levels of miR-15a-5p were downregulated. In addition, ANRIL was identified to bind to miR-15a-5p. The IL-13-induced upregulation of eotaxin-1, GM-CSF and MUC5AC mRNA expression and secretory levels was significantly inhibited by the genetic knockdown of ANRIL, while the miR-15a-5p inhibitor effectively reversed this effect. JAK2 was also discovered to be directly targeted by miR-15a-5p. The overexpression of JAK2 significantly suppressed the therapeutic effect of miR-15a-5p mimics on IL-13-induced inflammation in vitro. In conclusion, the findings of the present study suggested that the genetic knockdown of ANRIL may suppress the production of inflammatory cytokines and mucin in IL-13-treated HNECs via regulation of the miR-15a-5p/JAK2 axis. Thus, ANRIL may serve as a novel target for AR treatment.

Competing Endogenous RNA Networks as Biomarkers in Neurodegenerative Diseases

Protein aggregation is classically considered the main cause of neuronal death in neurodegenerative diseases (NDDs). However, increasing evidence suggests that alteration of RNA metabolism is a key factor in the etiopathogenesis of these complex disorders. Non-coding RNAs are the major contributor to the human transcriptome and are particularly abundant in the central nervous system, where they have been proposed to be involved in the onset and development of NDDs. Interestingly, some ncRNAs (such as lncRNAs, circRNAs and pseudogenes) share a common functionality in their ability to regulate gene expression by modulating miRNAs in a phenomenon known as the competing endogenous RNA mechanism. Moreover, ncRNAs are found in body fluids where their presence and concentration could serve as potential non-invasive biomarkers of NDDs. In this review, we summarize the ceRNA networks described in Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis and spinocerebellar ataxia type 7, and discuss their potential as biomarkers of these NDDs. Although numerous studies have been carried out, further research is needed to validate these complex interactions between RNAs and the alterations in RNA editing that could provide specific ceRNET profiles for neurodegenerative disorders, paving the way to a better understanding of these diseases.