HIV-associated sensory polyneuropathy and neuronal injury are associated with miRNA-455-3p induction

Potential diagnostic value of miRNAs in sexually transmitted infections

MiRNAs are small endogenous non-coding RNAs that have been demonstrated to be involved in post-transcriptional gene silencing, regulating a number of metabolic functions in the human body, including immune response, cellular physiology, organ development, angiogenesis, signaling, and other aspects. As popular molecules that have been studied in previous years, given their extensive regulatory functions, miRNAs hold considerable promise as non-invasive biomarkers. Sexually transmitted infections(STIs) are still widespread and have an adverse effect on individuals, communities, and society worldwide. miRNAs in the regulatory networks are generally involved in their molecular processes of formation and development. In this review, we discuss the value of miRNAs for the diagnosis of STIs.

miRNA contributes to neuropathic pains

Neuropathic pain (NP) is a kind of chronic pain caused by direct injury to the peripheral or central nervous system (CNS). microRNAs (miRNAs) are small noncoding RNAs that mostly interact with the 3 untranslated region of messenger RNAs (mRNAs) to regulate the expression of multiple genes. NP is characterized by changes in the expression of receptors and mediators, and there is evidence that miRNAs may contribute to some of these alterations. In this review, we aimed to fully comprehend the connection between NP and miRNA; and also, to establish a link between neurology, biology, and dentistry. Studies have shown that targeting miRNAs may be an effective therapeutic strategy for the treatment of chronic pain and potential target for the prevention of NP.

Narrative Review of the Complex Interaction between Pain and Trauma in Children: A Focus on Biological Memory, Preclinical Data, and Epigenetic Processes

The incidence and collective impact of early adverse experiences, trauma, and pain continue to increase. This underscores the urgent need for translational efforts between clinical and preclinical research to better understand the underlying mechanisms and develop effective therapeutic approaches. As our understanding of these issues improves from studies in children and adolescents, we can create more precise preclinical models and ultimately translate our findings back to clinical practice. A multidisciplinary approach is essential for addressing the complex and wide-ranging effects of these experiences on individuals and society. This narrative review aims to (1) define pain and trauma experiences in childhood and adolescents, (2) discuss the relationship between pain and trauma, (3) consider the role of biological memory, (4) decipher the relationship between pain and trauma using preclinical data, and (5) examine the role of the environment by introducing the importance of epigenetic processes. The ultimate scope is to better understand the wide-ranging effects of trauma, abuse, and chronic pain on children and adolescents, how they occur, and how to prevent or mitigate their effects and develop effective treatment strategies that address both the underlying causes and the associated physiological and psychological effects.

The Role of miRNAs in Neuropathic Pain

Neuropathic pain is a debilitating condition affecting around 8% of the adult population in the UK. The pathophysiology is complex and involves a wide range of processes, including alteration of neuronal excitability and synaptic transmission, dysregulated intracellular signalling and activation of pro-inflammatory immune and glial cells. In the past 15 years, multiple miRNAs–small non-coding RNA–have emerged as regulators of neuropathic pain development. They act by binding to target mRNAs and preventing the translation into proteins. Due to their short sequence (around 22 nucleotides in length), they can have hundreds of targets and regulate several pathways. Several studies on animal models have highlighted numerous miRNAs that play a role in neuropathic pain development at various stages of the nociceptive pathways, including neuronal excitability, synaptic transmission, intracellular signalling and communication with non-neuronal cells. Studies on animal models do not always translate in the clinic; fewer studies on miRNAs have been performed involving human subjects with neuropathic pain, with differing results depending on the specific aetiology underlying neuropathic pain. Further studies using human tissue and liquid samples (serum, plasma, saliva) will help highlight miRNAs that are relevant to neuropathic pain diagnosis or treatment, as biomarkers or potential drug targets.

Mechanisms behind diffuse idiopathic peripheral neuropathy in humans - a systematic review

Introduction: Diffuse peripheral neuropathy is a well-known complication of several conditions, whereas many patients have peripheral neuropathy of unknown etiology and pathophyisology. Increased knowledge of mechanisms may provide insight into enteric neuropathy with gastrointestinal dysmotility. The aim of the present systematic review was to identify mechanisms behind diffuse idiopathic peripheral neuropathies in humans.Methods: Searches were performed in PubMed, Embase, and Web of Science. Human original and review articles, written in English, describing mechanisms behind diffuse peripheral neuropathy verified by objective examinations were intended to be studied. Articles that described animal models, well-described hereditary diseases, drug-induced neuropathy, pain syndromes, malnutrition, and local neuropathy were excluded.Results: In total, 4712 articles were identified. After scrutinizing titles and abstracts, 633 remained and were studied in full text. After the removal of articles not fulfilling inclusion or exclusion criteria, 52 were finally included in this review. The most frequently described neuropathy was diabetic neuropathy, with a wide range of mechanisms involving mitochondrial dysfunction such as oxidative stress and inflammation. Microvascular changes in diabetes and vasculitis lead to ischemia and secondary oxidative stress with inflammation. Structural changes in neurons and glial cells are observed, with abnormalities in different neurotrophic factors. Neuropathy induced by autoantibodies or immunological mechanisms is described in infectious and systemic inflammatory diseases. Several ion channels may be involved in painful neuropathy. No study identified why some patients mainly develop large fiber neuropathy and others small fiber neuropathy.Conclusion: Metabolic and immunological factors and channelopathy may be considered in diffuse idiopathic peripheral neuropathy.

Alterations in circulating markers in HIV/AIDS patients with poor immune reconstitution: Novel insights from microbial translocation and innate immunity

After long-term anti-retroviral therapy (ART) treatment, most human immunodeficiency virus (HIV)/Acquired Immure Deficiency Syndrome (AIDS) patients can achieve virological suppression and gradual recovery of CD4⁺ T-lymphocyte (CD4⁺ T cell) counts. However, some patients still fail to attain normal CD4⁺ T cell counts; this group of patients are called immune non-responders (INRs), and these patients show severe immune dysfunction. The potential mechanism of poor immune reconstitution (PIR) remains unclear and the identification of uniform biomarkers to predict the occurrence of PIR is particularly vital. But limited information is available on the relationship between circulating markers of INRs and immune recovery. Hence, this review summarises alterations in the intestine microbiota and associated markers in the setting of PIR to better understand host-microbiota-metabolite interactions in HIV immune reconstitution and to identify biomarkers that can predict recovery of CD4⁺ T cell counts in INRs.

A Review of Molecular Interplay between Neurotrophins and miRNAs in Neuropsychological Disorders

Various neurotrophins (NTs), including nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3, and neurotrophin-4, promote cellular differentiation, survival, and maintenance, as well as synaptic plasticity, in the peripheral and central nervous system. The function of microRNAs (miRNAs) and other small non-coding RNAs, as regulators of gene expression, is pivotal for the appropriate control of cell growth and differentiation. There are positive and negative loops between NTs and miRNAs, which exert modulatory effects on different signaling pathways. The interplay between NTs and miRNAs plays a crucial role in the regulation of several physiological and pathological brain procedures. Emerging evidence suggests the diagnostic and therapeutic roles of the interactions between NTs and miRNAs in several neuropsychological disorders, including epilepsy, multiple sclerosis, Alzheimer's disease, Huntington's disease, amyotrophic lateral sclerosis, schizophrenia, anxiety disorders, depression, post-traumatic stress disorder, bipolar disorder, and drug abuse. Here, we review current data regarding the regulatory interactions between NTs and miRNAs in neuropsychological disorders, for which novel diagnostic and/or therapeutic strategies are emerging. Targeting NTs-miRNAs interactions for diagnostic or therapeutic approaches needs to be validated by future clinical studies.

Role of Epigenetic Mechanisms in Chronic Pain

Pain is an unpleasant but essential-to-life sensation, usually resulting from tissue damage. When pain persists long after the injury has resolved, it becomes pathological. The precise molecular and cellular mechanisms causing the transition from acute to chronic pain are not fully understood. A key aspect of pain chronicity is that several plasticity events happen along the neural pathways involved in pain. These long-lasting adaptive changes are enabled by alteration in the expression of relevant genes. Among the different modulators of gene transcription in adaptive processes in the nervous system, epigenetic mechanisms play a pivotal role. In this review, I will first outline the main classes of epigenetic mediators and then discuss their implications in chronic pain.

Comprehensive profiling and characterization of cellular microRNAs in response to coxsackievirus A10 infection in bronchial epithelial cells

Coxsackievirus A10 (CV-A10), the causative agent of hand, foot, and mouth disease (HFMD), caused a series of outbreaks in recent years and often leads to neurological impairment, but a clear understanding of the disease pathogenesis and host response remains elusive. Cellular microRNAs (miRNAs), a large family of non-coding RNA molecules, have been reported to be key regulators in viral pathogenesis and virus-host interactions. However, the role of host cellular miRNAs defensing against CV-A10 infection is still obscure. To address this issue, we systematically analyzed miRNA expression profiles in CV-A10-infected 16HBE cells by high-throughput sequencing methods in this study. It allowed us to successfully identify 312 and 278 miRNAs with differential expression at 12 h and 24 h post-CV-A10 infection, respectively. Among these, 4 miRNAs and their target genes were analyzed by RT-qPCR, which confirmed the sequencing data. Gene target prediction and enrichment analysis revealed that the predicted targets of these miRNAs were significantly enriched in numerous cellular processes, especially in regulation of basic physical process, host immune response and neurological impairment. And the integrated network was built to further indicate the regulatory roles of miRNAs in host-CV-A10 interactions. Consequently, our findings could provide a beneficial basis for further studies on the regulatory roles of miRNAs relevant to the host immune responses and neuropathogenesis caused by CV-A10 infection.

The etiological roles of miRNAs, lncRNAs, and circRNAs in neuropathic pain: A narrative review

Background

Non‐coding RNAs (ncRNAs) are involved in neuropathic pain development. Herein, we systematically searched for neuropathic pain‐related ncRNAs expression changes, including microRNAs (miRNAs), long non‐coding RNAs (lncRNAs), and circular non‐coding RNAs (circRNAs).

Methods

We searched two databases, PubMed and GeenMedical, for relevant studies.

Results

Peripheral nerve injury or noxious stimuli can induce extensive changes in the expression of ncRNAs. For example, higher serum miR‐132‐3p, ‐146b‐5p, and ‐384 was observed in neuropathic pain patients. Either sciatic nerve ligation, dorsal root ganglion (DRG) transaction, or ventral root transection (VRT) could upregulate miR‐21 and miR‐31 while downregulating miR‐668 and miR‐672 in the injured DRG. lncRNAs, such as early growth response 2‐antisense‐RNA (Egr2‐AS‐RNA) and Kcna2‐AS‐RNA, were upregulated in Schwann cells and inflicted DRG after nerve injury, respectively. Dysregulated circRNA homeodomain‐interacting protein kinase 3 (circHIPK3) in serum and the DRG, abnormally expressed lncRNAs X‐inactive specific transcript (XIST), nuclear enriched abundant transcript 1 (NEAT1), small nucleolar RNA host gene 1 (SNHG1), as well as ciRS‐7, zinc finger protein 609 (cirZNF609), circ_0005075, and circAnks1a in the spinal cord were suggested to participate in neuropathic pain development. Dysregulated miRNAs contribute to neuropathic pain via neuroinflammation, autophagy, abnormal ion channel expression, regulating pain‐related mediators, protein kinases, structural proteins, neurotransmission excitatory–inhibitory imbalances, or exosome miRNA‐mediated neuron–glia communication. In addition, lncRNAs and circRNAs are essential in neuropathic pain by acting as antisense RNA and miRNA sponges, epigenetically regulating pain‐related molecules expression, or modulating miRNA processing.

Conclusions

Numerous dysregulated ncRNAs have been suggested to participate in neuropathic pain development. However, there is much work to be done before ncRNA‐based analgesics can be clinically used for various reasons such as conservation among species, proper delivery, stability, and off‐target effects.

Integrated Analysis of the miRNA-mRNA Regulatory Network Involved in HIV-Associated Neurocognitive Disorder

HIV-associated neurocognitive disorder (HAND) is an array of neurocognitive changes associated with HIV infection, and the roles of microRNAs in HAND have not yet been completely revealed. Based on published data and publicly available databases, we constructed an integrated miRNA-mRNA network involved in HAND. Bioinformatics analyses, including gene ontology, network analysis, and KEGG pathway analysis, were applied for further study of the network and the genes of the network. The axon guidance KEGG pathway, three genes NTNG1, EFNB2, CXCL12, and 17 miRNAs which regulate these genes are spotlighted in our study. This study provides new perspectives to the knowledge of miRNAs’ roles in the progression of HAND, and our findings provide potential therapeutic targets and clues of HAND.

New Vistas in microRNA Regulatory Interactome in Neuropathic Pain

Neuropathic pain is a chronic pain condition seen in patients with diabetic neuropathy, cancer chemotherapy-induced neuropathy, idiopathic neuropathy as well as other diseases affecting the nervous system. Only a small percentage of people with neuropathic pain benefit from current medications. The complexity of the disease, poor identification/lack of diagnostic and prognostic markers limit current strategies for the management of neuropathic pain. Multiple genes and pathways involved in human diseases can be regulated by microRNA (miRNA) which are small non-coding RNA. Several miRNAs are found to be dysregulated in neuropathic pain. These miRNAs regulate expression of various genes associated with neuroinflammation and pain, thus, regulating neuropathic pain. Some of these key players include adenylate cyclase (Ac9), toll-like receptor 8 (Tlr8), suppressor of cytokine signaling 3 (Socs3), signal transducer and activator of transcription 3 (Stat3) and RAS p21 protein activator 1 (Rasa1). With advancements in high-throughput technology and better computational power available for research in present-day pharmacology, biomarker discovery has entered a very exciting phase. We dissect the architecture of miRNA biological networks encompassing both human and rodent microRNAs involved in the development of neuropathic pain. We delineate various microRNAs, and their targets, that may likely serve as potential biomarkers for diagnosis, prognosis, and therapeutic intervention in neuropathic pain. miRNAs mediate their effects in neuropathic pain by signal transduction through IRAK/TRAF6, TLR4/NF-κB, TXIP/NLRP3 inflammasome, MAP Kinase, TGFβ and TLR5 signaling pathways. Taken together, the elucidation of the landscape of signature miRNA regulatory networks in neuropathic pain will facilitate the discovery of novel miRNA/target biomarkers for more effective management of neuropathic pain.

Emerging role of non-coding RNAs in the course of HIV infection

Recent studies have shown that non-coding region of the human genome can exert important regulatory roles on critical biological functions, including response to viral infections, among them is human immunodeficiency virus (HIV). HIV/AIDS is characterized by a gradual diminution of CD4 + T cells resulting in progressive deterioration of host immune responses and eventually high vulnerability to opportunistic infections and cancer. T cells functions have been shown to be delicately regulated by an active functional network of non-coding RNAs. Several lncRNAs such as MALAT1, NEAT1, GAS5, LOC102549805, NKILA, BACE1-AS, LINC00313, RP11-539L10.2, PVT1, LINC00173, NRON and AK130181 have been found to affect response of immune system to HIV or its pathological consequences. Moreover, numerous miRNAs such as hsa-miR-191-5p, miR-155, miR-103, miR-107, miR-150, miR-144, miR-125b, miR-146a, miR-146b-5p and miR-15a are involved in this process. In the current manuscript, we explain the role of lncRNAs and miRNAs in the regulation of response to HIV infection, apoptosis and activity of T cells, reactivation or latency of this virus and even pathological manifestations such as Tat-mediated induction of astrocytic amyloidosis.

Plasma MicroRNA Signature Panel Predicts the Immune Response After Antiretroviral Therapy in HIV-Infected Patients

Background

Approximately 10–40% of people with human immunodeficiency virus (HIV) infection are unable to obtain successful improvements in immune function after antiretroviral therapy (ART). These patients are at greater risk of developing non-acquired immunodeficiency syndrome (AIDS)-related conditions, with the accompanying increased morbidity and mortality. Discovering predictive biomarkers can help to identify patients with a poor immune response earlier and provide new insights into the mechanisms of this condition.

Methods

A total of 307 people with HIV were enrolled, including 110 immune non-responders (INRs) and 197 immune responders (IRs). Plasma samples were taken before ART, and quantities of plasma microRNAs (miRNAs) were determined using reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR). Candidate biomarkers were established through four phases: discovery, training, validation, and blinded test. Binary logistic regression was used to analyze the combined predictive capacity of the identified miRNAs. The effect of one miRNA, miR-16-5p, on T cell function was assessed in vitro.

Results

Expression of five miRNAs (miR-580, miR-627, miR-138-5p, miR-16-5p, and miR-323-3p) was upregulated in the plasma of INRs compared with that in IRs. Expression of these miRNAs was negatively correlated with both CD4⁺ T cell counts and the increase in the proportion of CD4⁺ T cells after one year of ART. These five miRNAs were combined in a predictive model, which could effectively identify INRs or IRs. Furthermore, we found that miR-16-5p inhibits CD4⁺ T cell proliferation by regulating calcium flux.

Conclusion

We established a five-miRNA panel in plasma that accurately predicts poor immune response after ART, which could inform strategies to reduce the incidence of this phenomenon and improve the clinical management of these patients.

Construction and Investigation of Competing Endogenous RNA Networks and Candidate Genes Involved in SARS-CoV-2 Infection

Introduction

The current COVID-19 pandemic caused by a novel coronavirus SARS-CoV-2 is a quickly developing global health crisis, yet the mechanisms of pathogenesis in COVID-19 are not fully understood.

Methods

The RNA sequencing data of SARS-CoV-2-infected cells was obtained from the Gene Expression Omnibus (GEO). The differentially expressed mRNAs (DEmRNAs), long non-coding RNAs (DElncRNAs), and microRNAs (DEmiRNAs) were identified by edgeR, and the SARS-CoV-2-associated competing endogenous RNA (ceRNA) network was constructed based on the prediction of bioinformatic databases. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted with the SARS-CoV-2-related DEmRNAs, and the protein–protein interaction network was also built basing on STRING database. The ROC analysis was performed for assessing the diagnostic efficiency of hub genes.

Results

The results indicated that SARS-CoV-2-related DEmRNAs were associated with the interferon signaling pathway and other antiviral processes, such as IFNL3, IFNL1 and CH25H. Our analysis suggested that lncRNA NEAT1 might regulate the host immune response through two miRNAs, hsa-miR-374-5p and hsa-miR-155-5p, which control the expression of SOCS1, IL6, IL1B, CSF1R, CD274, TLR6, and TNF. Additionally, IFI6, HRASLS2, IGFBP4 and PTN may be potential targets based on an analysis comparing the transcriptional responses of SARS-CoV-2 infection with that of other respiratory viruses.

Discussion

The unique ceRNA network identified potential non-coding RNAs and their possible targets as well as a new perspective to understand the molecular mechanisms of the host immune response to SARS-CoV-2. This study may also aid in the development of innovative diagnostic and therapeutic strategies.

Predictive variables for peripheral neuropathy in treated HIV type 1 infection revealed by machine learning

OBJECTIVE

Peripheral neuropathies (PNPs) in HIV-infected patients are highly debilitating because of neuropathic pain and physical disabilities. We defined prevalence and associated predictive variables for PNP subtypes in a cohort of persons living with HIV.

DESIGN

Adult persons living with HIV in clinical care were recruited to a longitudinal study examining neurological complications.

METHODS

Each patient was assessed for symptoms and signs of PNP with demographic, laboratory, and clinical variables. Univariate, multiple logistic regression and machine learning analyses were performed by comparing patients with and without PNP.

RESULTS

Three patient groups were identified: PNP (n = 111) that included HIV-associated distal sensory polyneuropathy (n = 90) or mononeuropathy (n = 21), and non-neuropathy (n = 408). Univariate analyses showed multiple variables differed significantly between the non-neuropathy and PNP groups including age, estimated HIV type 1 (HIV-1) duration, education, employment, neuropathic pain, peak viral load, polypharmacy, diabetes, cardiovascular disorders, AIDS, and prior neurotoxic nucleoside antiretroviral drug exposure. Classification algorithms distinguished those with PNP, all with area under the receiver operating characteristic curve values of more than 0.80. Random forest models showed greater accuracy and area under the receiver operating characteristic curve values compared with the multiple logistic regression analysis. Relative importance plots showed that the foremost predictive variables of PNP were HIV-1 duration, peak plasma viral load, age, and low CD4+ T-cell levels.

CONCLUSION

PNP in HIV-1 infection remains common affecting 21.4% of patients in care. Machine-learning models uncovered variables related to PNP that were undetected by conventional analyses, emphasizing the importance of statistical algorithmic approaches to understanding complex neurological syndromes.

HIV Neuropathy-a Review of Mechanisms, Diagnosis, and Treatment of Pain

PURPOSE OF REVIEW

This article is a systematic review of data from 2018 to 2020 regarding information from publications on epidemiologic, diagnostic, and therapeutic advancements in human immunodeficiency virus-associated peripheral neuropathy.

RECENT FINDINGS

The epidemiology/pathology of HIV neuropathy is discussed. Diagnostics includes skin wrinkling-eutectic mixture of local anesthetic test and neurologic examinations. Therapeutic interventions include pharmacologic and nonpharmacologic management as well as self-management strategies. Peripheral neuropathy continues to affect the lives of persons living with HIV. First-line treatment with pregabalin or gabapentin for HIV neuropathic pain has limited data on adequate response. Exercise and self-management strategies may provide benefit in pain reduction. Continuing research on risk factors and biomarkers for HIV-related peripheral neuropathy will be critical for future diagnostic and therapeutic agents.

LncRNA SNHG15 Knockdown Protects Against OGD/R-Induced Neuron Injury by Downregulating TP53INP1 Expression via Binding to miR-455-3p

Cerebral ischemia-reperfusion (I/R) injury is the common symptom of ischemic stroke, which poses a heavy burden to human health. Long non-coding RNA (lncRNA) is indicated to be a critical regulator in cerebral ischemia. This study aims to reveal the effects of lncRNA small nucleolar RNA host gene 15 (SNHG15) on oxygen-glucose deprivation and reoxygenation (OGD/R)-induced neuron injury and underlying mechanism. The expression levels of SNHG15, microRNA-455-3p (miR-455-3p) and tumour protein p53 inducible nuclear protein 1 (TP53INP1) mRNA were determined by quantitative real time polymerase chain reaction in P12 cells. The protein levels of TP53INP1, cleaved caspase-3, caspase-3, B-cell lymphoma-2 and BCL2-associated x protein (Bax) were detected by western blot in P12 cells. Cell viability and apoptosis were revealed by cell counting kit-8 assay and flow cytometry analysis, respectively, in P12 cells. Caspase-3 activity, the levels of tumor necrosis factor-α and interleukin-1β and the production of reactive oxygen species (ROS) were severally determined by caspase-3 activity assay, Enzyme-linked immunosorbent assay and ROS detection assay in P12 cells. The binding relationship between miR-455-3p and SNHG15 or TP53INP1 was predicted by starbase online database, and identified by dual-luciferase reporter, RNA pull-down or RNA immunoprecipitation assay. SNHG15 expression and the mRNA and protein levels of TP53INP1 were dramatically upregulated, while miR-455-3p expression was apparently downregulated in OGD/R-induced PC12 cells. SNHG15 silencing hindered the effects of OGD/R treatment on cell viability, apoptosis, inflammation and oxidative in PC12 cells; however, these impacts were restored after miR-455-3p inhibitor transfection. Additionally, SNHG15 acted as a sponge of miR-455-3p and miR-455-3p bound to TP53INP1. SNHG15 contributed to OGD/R-induced neuron injury by regulating miR-455-3p/TP53INP1 axis, which provided a novel insight to study lncRNA-directed therapy in ischemia stoke.

Super-variants identification for brain connectivity

Identifying genetic biomarkers for brain connectivity helps us understand genetic effects on brain function. The unique and important challenge in detecting associations between brain connectivity and genetic variants is that the phenotype is a matrix rather than a scalar. We study a new concept of super‐variant for genetic association detection. Similar to but different from the classic concept of gene, a super‐variant is a combination of alleles in multiple loci but contributing loci can be anywhere in the genome. We hypothesize that the super‐variants are easier to detect and more reliable to reproduce in their associations with brain connectivity. By applying a novel ranking and aggregation method to the UK Biobank databases, we discovered and verified several replicable super‐variants. Specifically, we investigate a discovery set with 16,421 subjects and a verification set with 2,882 subjects, where they are formed according to release date, and the verification set is used to validate the genetic associations from the discovery phase. We identified 12 replicable super‐variants on Chromosomes 1, 3, 7, 8, 9, 10, 12, 15, 16, 18, and 19. These verified super‐variants contain single nucleotide polymorphisms that locate in 14 genes which have been reported to have association with brain structure and function, and/or neurodevelopmental and neurodegenerative disorders in the literature. We also identified novel loci in genes RSPO2 and TMEM74 which may be upregulated in brain issues. These findings demonstrate the validity of the super‐variants and its capability of unifying existing results as well as discovering novel and replicable results.

Sparse Multicategory Generalized Distance Weighted Discrimination in Ultra-High Dimensions

Distance weighted discrimination (DWD) is an appealing classification method that is capable of overcoming data piling problems in high-dimensional settings. Especially when various sparsity structures are assumed in these settings, variable selection in multicategory classification poses great challenges. In this paper, we propose a multicategory generalized DWD (MgDWD) method that maintains intrinsic variable group structures during selection using a sparse group lasso penalty. Theoretically, we derive minimizer uniqueness for the penalized MgDWD loss function and consistency properties for the proposed classifier. We further develop an efficient algorithm based on the proximal operator to solve the optimization problem. The performance of MgDWD is evaluated using finite sample simulations and miRNA data from an HIV study.

miR-455-3p alleviates propofol-induced neurotoxicity by reducing EphA4 expression in developing neurons

PURPOSE

Propofol, an aesthetic agent in paediatric patients, results in neurotoxicity in the developing neurons. To reduce side effects of propofol, the protective role of miR-455-3p (microRNA-455-3p) in developing rat brain was investigated.

MATERIALS AND METHODS

Primary hippocampal neurons were isolated from postnatal day 1 or 2 SD (Sprague-Dawley) rats. The neurons were exposed to various concentrations of propofol (0, 10, 30, or 50 μM) for 6 h. Propofol-induced cell viability was assessed by MTT assay, expression levels of miR-455-3p and EphA4 (erythropoietin-producing hepatocellular A4) in propofol-induced neurons were determined using qRT-PCR and western blot, respectively. Binding ability between miR-455-3p and EphA4 was predicted, and then validated by luciferase reporter assay. Neurons expressing miR-455-3p mimics, were treated with 50 μM propofol for 6 h, and apoptosis status was evaluated by flow cytometry.

RESULTS

Exposure to propofol significantly decreased cell viability of developing neurons isolated from neonatal rats. Propofol decreased miR-455-3p expression, while increased EphA4 level in the neurons. miR-455-3p mimics increased propofol-induced reduce in cell viability, and attenuated propofol-induced cell apoptosis of neurons. MiR-455-3p could target EphA4, and decreased expression of EphA4 in neurons exposure to propofol. EphA4 knockdown counteracted with the promotive effects of propofol on cell viability and apoptosis of neurons.

CONCLUSION

Propofol treatment induces neurotoxicity and suppresses miR-455-3p levels in the developing hippocampal neurons. However, miR-455-3p could alleviate such neurotoxicity by reducing EphA4 expression, provided new insights into miR-455-3p as novel therapeutic target to prevent propofol-induced damages from bench to clinic.

The delicate balance between neurotoxicity and neuroprotection in the context of HIV-1 infection

Human immunodeficiency virus type-1 (HIV-1) causes a spectrum of neurological impairments, termed HIV-associated neurocognitive disorder (HAND), following the infiltration of infected cells into the brain. Even though the implementation of antiretroviral therapy reduced the systemic viral load, the prevalence of HAND remains unchanged and infected patients develop persisting neurological disturbances affecting their quality of life. As a result, HAND have gained importance in basic and clinical researches, warranting the need of developing new adjunctive treatments. Nonetheless, a better understanding of the molecular and cellular mechanisms remains necessary. Several studies consolidated their efforts into elucidating the neurotoxic signaling leading to HAND including the deleterious actions of HIV-1 viral proteins and inflammatory mediators. However, the scope of these studies is not sufficient to address all the complexity related to HAND development. Fewer studies focused on an altered neuroprotective capacity of the brain to respond to HIV-1 infection. Neurotrophic factors are endogenous polyproteins involved in neuronal survival, synaptic plasticity, and neurogenesis. Any defects in the processing or production of these crucial factors might compose a risk factor rendering the brain more vulnerable to neuronal damages. Due to their essential roles, they have been investigated for their diverse interplays with HIV-1 infection. In this review, we present a complete description of the neurotrophic factors involved in HAND. We discuss emerging concepts for their therapeutic applications and summarize the complex mechanisms that down-regulate their production in favor of a neurotoxic environment. For certain factors, we finally address opposing roles that rather lead to increased inflammation.

Non-coding RNAs in neuropathic pain

Neuro-immune alterations in the peripheral and central nervous system play a role in the pathophysiology of chronic pain in general, and members of the non-coding RNA (ncRNA) family, specifically the short, 22 nucleotide microRNAs (miRNAs) and the long non-coding RNAs (lncRNAs) act as master switches orchestrating both immune as well as neuronal processes. Several chronic disorders reveal unique ncRNA expression signatures, which recently generated big hopes for new perspectives for the development of diagnostic applications. lncRNAs may offer perspectives as candidates indicative of neuropathic pain in liquid biopsies. Numerous studies have provided novel mechanistic insight into the role of miRNAs in the molecular sequelae involved in the pathogenesis of neuropathic pain along the entire pain pathway. Specific processes within neurons, immune cells, and glia as the cellular components of the neuropathic pain triad and the communication paths between them are controlled by specific miRNAs. Therefore, nucleotide sequences mimicking or antagonizing miRNA actions can provide novel therapeutic strategies for pain treatment, provided their human homologues serve the same or similar functions. Increasing evidence also sheds light on the function of lncRNAs, which converge so far mainly on purinergic signalling pathways both in neurons and glia, and possibly even other ncRNA species that have not been explored so far.

Light exercise without lactate elevation induces ischemic tolerance through the modulation of microRNA in the gerbil hippocampus

Previously we studied the possible neuroprotective effects of ischemia-resistant exercise in a gerbil model of transient whole-brain ischemia and evaluated the histology, expression of specific proteins, and brain function under different conditions. The present study investigated the neuroprotective effects of light exercise, without lactate elevation, in a gerbil model of ischemia/reperfusion injury. Transient whole-brain ischemia was induced by occlusion of the bilateral common carotid arteries for 5 min. A group of animals was subjected to treadmill exercise before ischemia induction. Hippocampal neuronal damage and miRNA expression, as well as behavioral deficits and plasma lactate levels, were evaluated. Light exercise suppressed hippocampal neuron loss and preserved short-term memory. Moreover, 14 miRNAs (mmu-miR-211-3p, -327, -451b, -711, -3070-3p, -3070-2-3p, -3097-5p, -3620-5p, -6240, -6916-5p, -6944-5p, 7083-5p, -7085-5p, and -7674-5p) were upregulated and 6 miRNAs (mmu-miR-148b-3p, -152-3p, -181c-5p, -299b-5p, -455-3p, and -664-3p) were downregulated due to ischemia. However, the expression of these miRNAs remained unchanged when animals performed light exercise before the ischemic event. Differentially expressed miRNAs regulate multiple biological processes such as inflammation, metabolism, and cell death. These findings suggest that light exercise reduces neuronal death and behavioral deficits after transient ischemia by regulating hippocampal miRNAs.

[Trichostatin A suppresses up-regulation of histone deacetylase 4 and reverses differential expressions of miRNAs in the spinal cord of rats with chronic constrictive injury]

OBJECTIVE

To explore the analgesic mechanism of intrathecal trichostatin A (TSA) injection in a rat model of neuropathic pain induced by chronic constrictive injury (CCI).

METHODS

Male SD rats were randomized into sham operation+ DMSO group (group S), CCI +DMSO group (group C), CCI +10 μg TSA group (group T), and in the latter two groups, rat models of neuropathic pain were established induced by CCI. The rats were given intrathecal injections of 10 μL 5% DMSO or 10 μg TSA (in 5% DMSO) once a day on days 7 to 9 after CCI or sham operation. The rats were euthanized after behavioral tests on day 10, and the lumbar segment of the spinal cord was sampled to determine the expression of histone deacetylase 4 (HDAC4) protein and mRNA and detect the differentially expressed miRNAs using a miRNA chip. MiR-190b-5p and miR-142-3p were selected for validation of the results using RT-qPCR.

RESULTS

Compared with those in group S, the rats in group C showed significantly decreased paw withdrawal mechanical threshold (PWMT) from day 3 to day 10 after CCI (P < 0.05); intrathecal injection of TSA significantly reversed the reduction of PWMT following CCI (P < 0.05). Positive HDAC4 expression was detected mainly in the cytoplasm of the neurons in the gray matter of the spinal cord, and was obviously up-regulated after CCI (Ρ < 0.05). Intrathecal injection of TSA significantly suppressed CCI-induced up-regulation of HDAC4 at 10 days after the operation (P < 0.05). Compared with the miRNA profile in group S, miRNA profiling identified 83 differentially expressed miRNAs in group C (fold change ≥2 or ≤0.5, P < 0.05); TSA treatment reversed the expressions of 58 of the differentially expressed miRNAs following CCI, including 41 miRNAs that were decreased after CCI but up-regulated following TSA treatment. The results of real-time PCR validated the changes in the expressions of miR-190b-5p and miR-142-3p.

CONCLUSIONS

TSA suppresses CCI-induced up-regulation of HDAC4 and reverses differential expressions of miRNAs in the spinal cord of rats, which may contribute to the analgesic effect of TSA on neuropathic pain.