Antisense miR-132 blockade via the AChE-R splice variant mitigates cortical inflammation

Non-Coding RNAs in Neurological and Neuropsychiatric Disorders: Unraveling the Hidden Players in Disease Pathogenesis

Neurological and neuropsychiatric disorders pose substantial challenges to public health, necessitating a comprehensive understanding of the molecular mechanisms underlying their pathogenesis. In recent years, the focus has shifted toward the intricate world of non-coding RNAs (ncRNAs), a class of RNA molecules that do not encode proteins but play pivotal roles in gene regulation and cellular processes. This review explores the emerging significance of ncRNAs in the context of neurological and neuropsychiatric disorders, shedding light on their diverse functions and regulatory mechanisms. The dysregulation of various ncRNAs, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), has been implicated in the pathophysiology of conditions such as Alzheimer's disease, Parkinson's disease, schizophrenia, and mood disorders. This review delves into the specific roles these ncRNAs play in modulating key cellular processes, including synaptic plasticity, neuroinflammation, and apoptosis, providing a nuanced understanding of their impact on disease progression. Furthermore, it discusses the potential diagnostic and therapeutic implications of targeting ncRNAs in neurological and neuropsychiatric disorders. The identification of specific ncRNA signatures holds promise for the development of novel biomarkers for early disease detection, while the manipulation of ncRNA expression offers innovative therapeutic avenues. Challenges and future directions in the field are also considered, highlighting the need for continued research to unravel the complexities of ncRNA-mediated regulatory networks in the context of neurological and neuropsychiatric disorders. This review aims to provide a comprehensive overview of the current state of knowledge and stimulate further exploration into the fascinating realm of ncRNAs in the brain's intricate landscape.

Brain microRNAs are associated with variation in cognitive trajectory in advanced age

In advancing age, some individuals maintain a stable cognitive performance over time, while others experience a rapid decline. Such variation in cognitive trajectory is only partially explained by common neurodegenerative pathologies. Hence, we aimed to identify new molecular processes underlying variation in cognitive trajectory using brain microRNA profile followed by an integrative analysis with brain transcriptome and proteome. Individual cognitive trajectories were derived from longitudinally assessed cognitive-test scores of older-adult brain donors from four longitudinal cohorts. Postmortem brain microRNA profiles, transcriptomes, and proteomes were derived from the dorsolateral prefrontal cortex. The global microRNA association study of cognitive trajectory was performed in a discovery (n = 454) and replication cohort (n = 134), followed by a meta-analysis that identified 6 microRNAs. Among these, miR-132-3p and miR-29a-3p were most significantly associated with cognitive trajectory. They explain 18.2% and 2.0% of the variance of cognitive trajectory, respectively, and act independently of the eight measured neurodegenerative pathologies. Furthermore, integrative transcriptomic and proteomic analyses revealed that miR-132-3p was significantly associated with 24 of the 47 modules of co-expressed genes of the transcriptome, miR-29a-3p with 3 modules, and identified 84 and 214 downstream targets of miR-132-3p and miR-29a-3p, respectively, in cognitive trajectory. This is the first global microRNA study of cognitive trajectory to our knowledge. We identified miR-29a-3p and miR-132-3p as novel and robust contributors to cognitive trajectory independently of the eight known cerebral pathologies. Our findings lay a foundation for future studies investigating mechanisms and developing interventions to enhance cognitive stability in advanced age.

Age-Dependent and Pathway-Specific Bimodal Action of Nicotine on Synaptic Plasticity in the Hippocampus of Mice Lacking the miR-132/212 Genes

Nicotine addiction develops predominantly during human adolescence through smoking. Self-administration experiments in rodents verify this biological preponderance to adolescence, suggesting evolutionary-conserved and age-defined mechanisms which influence the susceptibility to nicotine addiction. The hippocampus, a brain region linked to drug-related memory storage, undergoes major morpho-functional restructuring during adolescence and is strongly affected by nicotine stimulation. However, the signaling mechanisms shaping the effects of nicotine in young vs. adult brains remain unclear. MicroRNAs (miRNAs) emerged recently as modulators of brain neuroplasticity, learning and memory, and addiction. Nevertheless, the age-dependent interplay between miRNAs regulation and hippocampal nicotinergic signaling remains poorly explored. We here combined biophysical and pharmacological methods to examine the impact of miRNA-132/212 gene-deletion (miRNA-132/212-/-) and nicotine stimulation on synaptic functions in adolescent and mature adult mice at two hippocampal synaptic circuits: the medial perforant pathway (MPP) to dentate yrus (DG) synapses (MPP-DG) and CA3 Schaffer collaterals to CA1 synapses (CA3-CA1). Basal synaptic transmission and short-term (paired-pulse-induced) synaptic plasticity was unaltered in adolescent and adult miRNA-132/212-/- mice hippocampi, compared with wild-type controls. However, nicotine stimulation promoted CA3-CA1 synaptic potentiation in mature adult (not adolescent) wild-type and suppressed MPP-DG synaptic potentiation in miRNA-132/212-/- mice. Altered levels of CREB, Phospho-CREB, and acetylcholinesterase (AChE) expression were further detected in adult miRNA-132/212-/- mice hippocampi. These observations propose miRNAs as age-sensitive bimodal regulators of hippocampal nicotinergic signaling and, given the relevance of the hippocampus for drug-related memory storage, encourage further research on the influence of miRNAs 132 and 212 in nicotine addiction in the young and the adult brain.

Regulators of cholinergic signaling in disorders of the central nervous system

Cholinergic signaling is crucial in cognitive processes, and degenerating cholinergic projections are a pathological hallmark in dementia. Use of cholinesterase inhibitors is currently the main treatment option to alleviate symptoms of Alzheimer's disease and has been postulated as a therapeutic strategy in acute brain damage (stroke and traumatic brain injury). However, the benefits of this treatment are still not clear. Importantly, cholinergic receptors are expressed both by neurons and by astrocytes and microglia, and binding of acetylcholine to the α7 nicotinic receptor in glial cells results in anti-inflammatory response. Similarly, the brain fine-tunes the peripheral immune response over the cholinergic anti-inflammatory axis. All of these processes are of importance for the outcome of acute and chronic neurological disease. Here, we summarize the main findings about the role of cholinergic signaling in brain disorders and provide insights into the complexity of molecular regulators of cholinergic responses, such as microRNAs and transfer RNA fragments, both of which may fine-tune the orchestra of cholinergic mRNAs. The available data suggest that these small noncoding RNA regulators may include promising biomarkers for predicting disease course and assessing treatment responses and might also serve as drug targets to attenuate signaling cascades during overwhelming inflammation and to ameliorate regenerative capacities of neuroinflammation.

miRNA-132/212 Gene-Deletion Aggravates the Effect of Oxygen-Glucose Deprivation on Synaptic Functions in the Female Mouse Hippocampus

Cerebral ischemia and its sequelae, which include memory impairment, constitute a leading cause of disability worldwide. Micro-RNAs (miRNA) are evolutionarily conserved short-length/noncoding RNA molecules recently implicated in adaptive/maladaptive neuronal responses to ischemia. Previous research independently implicated the miRNA-132/212 cluster in cholinergic signaling and synaptic transmission, and in adaptive/protective mechanisms of neuronal responses to hypoxia. However, the putative role of miRNA-132/212 in the response of synaptic transmission to ischemia remained unexplored. Using hippocampal slices from female miRNA-132/212 double-knockout mice in an established electrophysiological model of ischemia, we here describe that miRNA-132/212 gene-deletion aggravated the deleterious effect of repeated oxygen-glucose deprivation insults on synaptic transmission in the dentate gyrus, a brain region crucial for learning and memory functions. We also examined the effect of miRNA-132/212 gene-deletion on the expression of key mediators in cholinergic signaling that are implicated in both adaptive responses to ischemia and hippocampal neural signaling. miRNA-132/212 gene-deletion significantly altered hippocampal AChE and mAChR-M1, but not α7-nAChR or MeCP2 expression. The effects of miRNA-132/212 gene-deletion on hippocampal synaptic transmission and levels of cholinergic-signaling elements suggest the existence of a miRNA-132/212-dependent adaptive mechanism safeguarding the functional integrity of synaptic functions in the acute phase of cerebral ischemia.

Inflammatory signaling mechanisms in bipolar disorder

Bipolar disorder is a decidedly heterogeneous and multifactorial disease, with a high individual and societal burden. While not all patients display overt markers of elevated inflammation, significant evidence suggests that aberrant immune signaling contributes to all stages of the disease, and likely explains the elevated rates of comorbid inflammatory illnesses seen in this population. While individual systems have been intensely studied and targeted, a relative paucity of attention has been given to the interconnecting role of inflammatory signals therein. This review presents an updated overview of some of the most prominent pathophysiologic mechanisms in bipolar disorder, from mitochondrial, endoplasmic reticular, and calcium homeostasis, to purinergic, kynurenic, and hormonal/neurotransmitter signaling, showing inflammation to act as a powerful nexus between these systems. Several areas with a high degree of mechanistic convergence within this paradigm are highlighted to present promising future targets for therapeutic development and screening.

Differentially expressed genes, lncRNAs, and competing endogenous RNAs in Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is an acute and febrile systemic vasculitis of unknown etiology. This study aimed to identify the competing endogenous RNA (ceRNA) networks of lncRNAs, miRNAs, and genes in KD and explore the molecular mechanisms underlying KD.

METHODS

GSE68004 and GSE73464 datasets were downloaded from the Gene Expression Omnibus. Differentially expressed lncRNAs (DElncRNAs) and genes (DEGs) in KD were identified using the criteria of p < 0.05 and | log2 (fold change) | ≥ 1. MicroRNAs (miRNAs) related to KD were searched from databases. The lncRNA-miRNA-mRNA networks involving the DElncRNAs and DEGs were constructed.

RESULTS

A total of 769 common upregulated, 406 common downregulated DEGs, and six DElncRNAs were identified in the KD samples. The lncRNA-miRNA-mRNA network consisted of four miRNAs, three lncRNAs (including the upregulated PSORS1C3, LINC00999, and the downregulated SNHG5) and four DEGs (including the downregulated GATA3 and the upregulated SOD2, MAPK14, and PPARG). Validation in the GSE18606 dataset showed that intravenous immunoglobulin treatment significantly alleviated the deregulated profiles of the above RNAs in KD patients. Three ceRNA networks of LINC00999-hsa-miR-6780-SOD2, PSORS1C3-hsa-miR-216a-PPARG/MAPK14, and SNHG5-hsa-miR-132/hsa-miR-92-GATA3 were identified. Four genes were associated with functional categories, such as inflammatory response and vascular endothelial cell.

CONCLUSIONS

The ceRNA networks involve genes, such as SOD2, MAPK14, and PPARG, and lncRNAs, including PSORS1C3, LINC00999, and SNHG5, which might play a key role in the pathogenesis and development of KD by regulating inflammation.

Nicotine abolishes memory-related synaptic strengthening and promotes synaptic depression in the neurogenic dentate gyrus of miR-132/212 knockout mice

Micro-RNAs (miRNAs) are highly evolutionarily conserved short-length/noncoding RNA molecules that modulate a wide range of cellular functions in many cell types by regulating the expression of a variety of targeted genes. miRNAs have also recently emerged as key regulators of neuronal genes mediating the effects of psychostimulant drugs and memory-related neuroplasticity processes. Smoking is a predominant addictive behaviour associated with millions of deaths worldwide, and nicotine is a potent natural psychoactive agonist of cholinergic receptors, highly abundant in cigarettes. The influence of miRNAs modulation on cholinergic signalling in the nervous system remains however poorly explored. Using miRNA knockout mice and biochemical, electrophysiological and pharmacological approaches, we examined the effects of miR-132/212 gene disruption on the levels of hippocampal nicotinic acetylcholine receptors, total ERK and phosphorylated ERK (pERK) and MeCP2 protein levels, and studied the impact of nicotine stimulation on hippocampal synaptic transmission and synaptic depression and strengthening. miR-132/212 deletion significantly altered α7-nAChR and pERK protein levels, but not total ERK or MeCP2, and resulted in both exacerbated synaptic depression and virtually abolished memory-related synaptic strengthening upon nicotine stimulation. These observations reveal a functional miRNAs/nicotinergic signalling interplay critical for nicotinic-receptor expression and neuroplasticity in brain structures relevant for drug addiction and learning and memory functions.

The Neat Dance of COVID-19: NEAT1, DANCR, and Co-Modulated Cholinergic RNAs Link to Inflammation

The COVID-19 pandemic exerts inflammation-related parasympathetic complications and post-infection manifestations with major inter-individual variability. To seek the corresponding transcriptomic origins for the impact of COVID-19 infection and its aftermath consequences, we sought the relevance of long and short non-coding RNAs (ncRNAs) for susceptibility to COVID-19 infection. We selected inflammation-prone men and women of diverse ages among the cohort of Genome Tissue expression (GTEx) by mining RNA-seq datasets from their lung, and blood tissues, followed by quantitative qRT-PCR, bioinformatics-based network analyses and thorough statistics compared to brain cell culture and infection tests with COVID-19 and H1N1 viruses. In lung tissues from 57 inflammation-prone, but not other GTEx donors, we discovered sharp declines of the lung pathology-associated ncRNA DANCR and the nuclear paraspeckles forming neuroprotective ncRNA NEAT1. Accompanying increases in the acetylcholine-regulating transcripts capable of controlling inflammation co-appeared in SARS-CoV-2 infected but not H1N1 influenza infected lung cells. The lung cells-characteristic DANCR and NEAT1 association with inflammation-controlling transcripts could not be observed in blood cells, weakened with age and presented sex-dependent links in GTEx lung RNA-seq dataset. Supporting active involvement in the inflammatory risks accompanying COVID-19, DANCR's decline associated with decrease of the COVID-19-related cellular transcript ACE2 and with sex-related increases in coding transcripts potentiating acetylcholine signaling. Furthermore, transcription factors (TFs) in lung, brain and cultured infected cells created networks with the candidate transcripts, indicating tissue-specific expression patterns. Supporting links of post-infection inflammatory and cognitive damages with cholinergic mal-functioning, man and woman-originated cultured cholinergic neurons presented differentiation-related increases of DANCR and NEAT1 targeting microRNAs. Briefly, changes in ncRNAs and TFs from inflammation-prone human lung tissues, SARS-CoV-2-infected lung cells and man and woman-derived differentiated cholinergic neurons reflected the inflammatory pathobiology related to COVID-19. By shifting ncRNA differences into comparative diagnostic and therapeutic profiles, our RNA-sequencing based Resource can identify ncRNA regulating candidates for COVID-19 and its associated immediate and predicted long-term inflammation and neurological complications, and sex-related therapeutics thereof. Our findings encourage diagnostics of involved tissue, and further investigation of NEAT1-inducing statins and anti-cholinergic medications in the COVID-19 context.

Interacting with α 7 nAChR is a new mechanism for AChE to enhance the inflammatory response in macrophages

Acetylcholine (ACh) regulates inflammation via α7 nicotinic acetylcholine receptor (α7 nAChR). Acetylcholinesterase (AChE), an enzyme hydrolyzing ACh, is expressed in immune cells suggesting non-classical function in inflammatory responses. Here, the expression of PRiMA-linked G4 AChE was identified on the surface of macrophages. In lipopolysaccharide-induced inflammatory processes, AChE was upregulated by the binding of NF-κB onto the ACHE promotor. Conversely, the overexpression of G4 AChE inhibited ACh-suppressed cytokine release and cell migration, which was in contrast to that of applied AChE inhibitors. AChEmt, a DNA construct without enzymatic activity, was adopted to identify the protein role of AChE in immune system. Overexpression of G4 AChEmt induced cell migration and inhibited ACh-suppressed cell migration. The co-localization of α7 nAChR and AChE was found in macrophages, suggesting the potential interaction of α7 nAChR and AChE. Besides, immunoprecipitation showed a close association of α7 nAChR and AChE protein in cell membrane. Hence, the novel function of AChE in macrophage by interacting with α7 nAChR was determined. Together with hydrolysis of ACh, AChE plays a direct role in the regulation of inflammatory response. As such, AChE could serve as a novel target to treat age-related diseases by anti-inflammatory responses.

The role of microRNAs in neurons and neuroimmune communication in the dorsal root ganglia in chronic pain

Despite being a life-restricting condition, chronic pain remains poorly treated. A better understanding of the underlying mechanisms of chronic pain and thence development of innovative targets is therefore essential. Recently we have started to elucidate the importance of the role of microRNAs (miRs) in preclinical chronic pain. miRs are small, non-coding RNAs that regulate genes including those involved in nociceptive signalling. MiRs can exert their effects both intracellularly and extracellularly, the latter of which requires that they are released either as naked species or packaged in exosomes. Here we discuss changes in miR expression that occur in the dorsal root ganglia in murine models of chronic pain. We consider the downstream targets of changes in miR expression, including voltage-gated ion channels, as well as discuss extracellular consequences such as changes in macrophage phenotype that constitute of means by which neuron-immune cell crosstalk occurs. Such miR-mediated intracellular communication could provide a novel target for the treatment of chronic pain, which would be most effective if tailored to the specific cause of pain. Indeed, we conclude by reviewing evidence for the involvement of miRs in clinical cases of chronic pain, supporting the notion that tailored, miR-targeted therapies could prove to be an effective new strategy for the treatment of chronic pain clinically.

Cationic Magnetite Nanoparticles for Increasing siRNA Hybridization Rates

An investigation of the interaction principles of nucleic acids and nanoparticles is a priority for the development of theoretical and methodological approaches to creating bionanocomposite structures, which determines the area and boundaries of biomedical use of developed nanoscale devices. «Nucleic acid-magnetic nanoparticle» type constructs are being developed to carry out the highly efficient detection of pathogens, create express systems for genotyping and sequencing, and detect siRNA. However, the data available on the impact of nanoparticles on the behavior of siRNA are insufficient. In this work, using nanoparticles of two classical oxides of inorganic chemistry (magnetite (Fe₃O₄) and silica (SiO₂) nanoparticles), and widely used gold nanoparticles, we show their effect on the rate of siRNA hybridization. It has been determined that magnetite nanoparticles with a positive charge on the surface increase the rate of siRNA hybridization, while negatively charged magnetite and silica nanoparticles, or positively charged gold nanoparticles, do not affect hybridization rates (HR).

Central and peripheral anti-inflammatory effects of acetylcholinesterase inhibitors

Acetylcholinesterase (AChE) inhibitors modulate acetylcholine hydrolysis and hence play a key role in determining the cholinergic tone and in implementing its impact on the cholinergic blockade of inflammatory processes. Such inhibitors may include rapidly acting small molecule AChE-blocking drugs and poisonous anti-AChE insecticides or war agent inhibitors which penetrate both body and brain. Notably, traumatized patients may be hyper-sensitized to anti-AChEs due to their impaired cholinergic tone, higher levels of circulation pro-inflammatory cytokines and exacerbated peripheral inflammatory responses. Those largely depend on the innate-immune system yet reach the brain via vagus pathways and/or disrupted blood-brain-barrier. Other regulators of the neuro-inflammatory cascade are AChE-targeted microRNAs (miRs) and synthetic chemically protected oligonucleotide blockers thereof, whose size prevents direct brain penetrance. Nevertheless, these larger molecules may exert parallel albeit slower inflammatory regulating effects on brain and body tissues. Additionally, oligonucleotide aptamers interacting with innate immune Toll-Like Receptors (TLRs) may control inflammation through diverse routes and in different rates. Such aptamers may compete with the action of both small molecule inhibitors and AChE-inhibiting miRs in peripheral tissues including muscle and intestine. However, rapid adaptation processes, visualized in neuromuscular junctions enable murine survival under otherwise lethal anti-cholinesterase exposure; and both miR inhibitors and TLR-modulating aptamers may exert body-brain signals protecting experimental mice from acute inflammation. The complex variety of AChE inhibiting molecules identifies diverse body-brain communication pathways which may rapidly induce long-lasting central reactions to peripheral stressful and inflammatory insults in both mice and men. This article is part of the special issue entitled 'Acetylcholinesterase Inhibitors: From Bench to Bedside to Battlefield'.

Integrated miRNA-/mRNA-Seq of the Habenulo-Interpeduncular Circuit During Acute Nicotine Withdrawal

Tobacco use is the leading preventable cause of mortality in the world. The limited number of smoking cessation aids currently available are minimally effective, highlighting the need for novel therapeutic interventions. We describe a genome-wide approach to identify potential candidates for such interventions. Next-generation sequencing was performed using RNA isolated from the habenulo-interpeduncular circuit of male mice withdrawn from chronic nicotine treatment. This circuit plays a central role in the nicotine withdrawal response. Differentially expressed miRNAs and mRNAs were validated using RT-qPCR. Many of the differentially expressed mRNAs are predicted targets of reciprocally expressed miRNAs. We illustrate the utility of the dataset by demonstrating that knockdown in the interpeduncular nucleus of a differentially expressed mRNA, that encoding profilin 2, is sufficient to induce anxiety-related behavior. Importantly, profilin 2 knockdown in the ventral tegmental area did not affect anxiety behavior. Our data reveal wide-spread changes in gene expression within the habenulo-interpeduncular circuit during nicotine withdrawal. This dataset should prove to be a valuable resource leading to the identification of substrates for the design of innovative smoking cessation aids.

Endoplasmic reticulum stress is involved in lipopolysaccharide-induced inflammatory response and apoptosis in goat endometrial stromal cells

Endoplasmic reticulum (ER) stress is involved in regulating cell metabolism, apoptosis, autophagy, and survival. However, there is not enough information about the role of ER stress in lipopolysaccharide (LPS)-induced apoptosis and inflammatory cytokine secretion in the uterus. In this study, we found that LPS induced apoptosis and inflammation in goat endometrial stromal cells (ESCs). LPS treatment inhibited cell viability and cell proliferation. In addition, the genes associated with proliferation, such as proliferating cell nuclear antigen and MKI67, were affected by LPS treatment. Moreover, LPS increased the secretion of interleukin (IL)-1β and IL-8, promoting the levels of MYD88, caspase1, and TRL4. The 4-phenylbutyric acid pretreatment inhibited the expression of unfolded protein response proteins and the secretion of inflammatory cytokines in LPS-treated cells. However, blockage of inositol-requiring enzyme 1 and activating transcription factor 6 did not significantly reduce apoptosis and inflammatory cytokine secretion. Collectively, ER stress involved in LPS-induced apoptosis and inflammatory cytokine increased in goat ESCs. This study provides new insight into the function of ER stress in the pathological process.

Current understanding of fear learning and memory in humans and animal models and the value of a linguistic approach for analyzing fear learning and memory in humans

Fear is an emotion that serves as a driving factor in how organisms move through the world. In this review, we discuss the current understandings of the subjective experience of fear and the related biological processes involved in fear learning and memory. We first provide an overview of fear learning and memory in humans and animal models, encompassing the neurocircuitry and molecular mechanisms, the influence of genetic and environmental factors, and how fear learning paradigms have contributed to treatments for fear-related disorders, such as posttraumatic stress disorder. Current treatments as well as novel strategies, such as targeting the perisynaptic environment and use of virtual reality, are addressed. We review research on the subjective experience of fear and the role of autobiographical memory in fear-related disorders. We also discuss the gaps in our understanding of fear learning and memory, and the degree of consensus in the field. Lastly, the development of linguistic tools for assessments and treatment of fear learning and memory disorders is discussed.

Bio-inspired nanozyme: a hydratase mimic in a zeolitic imidazolate framework

Nanozymes provide comparative advantages over natural enzymes and conventional artificial enzymes for catalytic reactions. However, nanozymes are only suitable for limited types of reactions, whose catalytic principles are not yet fully revealed. Herein, a new nanozyme based on a bionic zeolitic imidazolate framework is proposed. Zeolitic imidazolate framework-8 (ZIF-8) possesses a similar geometric structure to that of the active center of human carbonic anhydrase II (hCAII) and exhibits catalytic performance analogous to that of the hCAII. The less imidazolate coordinated zinc cations on the external surface of ZIF-8 can act as Lewis acid sites, lowering the pKa of Zn-bound H2O molecules from 14 to 8.4, which facilitates the deprotonation of H2O molecules and generation of zinc-bound hydroxide nucleophiles. The esterase-like ZIF-8 nanozyme shows a similar affinity to p-nitrophenyl acetate compared with hCAII. The ZIF-8 nanozyme also promotes CO2 hydration and acetylthiocholine hydrolysis reaction, and a series of ZIFs are also found with intrinsic enzyme-like activities due to similar compositions and spatial structures. These results imply that the bionic nanoparticles can be developed to fabricate a new generation of nanozymes by mimicking the active sites of natural enzymes.

miR-513a-5p targets Bcl-2 to promote dichlorvos induced apoptosis in HK-2 cells

miRNAs are crucially involved in cellular responses to exotic chemical toxins. However, the role of miRNAs in organophosphates induced cytotoxicity is poorly understood. In present study, we investigated the role of miR-513a-5p in dichlorvos induced cytotoxicity in human kidney cell line HK-2. We found that dichlorvos increased intracellular ROS level, upregulated miR-513a-5p expression and induced apoptosis in HK-2 cells. Moreover, overexpression of miR-513a-5p promoted apoptosis of HK-2 cells with or without exposure to dichlorvos while anti-miR-513a-5p partially suppressed dichlorvos induced apoptosis. Luciferase assay showed that miR-513a-5p could directly bind to the 3'-untranslated regions of Bcl-2. Furthermore, miR-513a-5p decreased the level of Bcl-2 and promoted dichlorvos induced apoptosis in HK-2 cells through the Bcl-2/Bax-Caspase-3 pathway. Taken together, our findings indicate that miR-513a-5p promotes dichlorvos induced apoptosis by targeting Bcl-2.

Erythropoietin regulates the expression of dimeric form of acetylcholinesterase during differentiation of erythroblast

Acetylcholinesterase (AChE; EC 3.1.1.7) is known to hydrolyze acetylcholine at cholinergic synapses. In mammalian erythrocyte, AChE exists as a dimer (G₂ ) and is proposed to play role in erythropoiesis. To reveal the regulation of AChE during differentiation of erythroblast, erythroblast-like cells (TF-1) were induced to differentiate by application of erythropoietin (EPO). The expression of AChE was increased in parallel to the stages of differentiation. Application of EPO in cultured TF-1 cells induced transcriptional activity of ACHE gene, as well as its protein product. This EPO-induced event was in parallel with erythrocytic proteins, for example, α- and β-globins. The EPO-induced AChE expression was mediated by phosphorylations of Akt and GATA-1; because the application of Akt kinase inhibitor blocked the gene activation. Erythroid transcription factor also known as GATA-1, a downstream transcription factor of EPO signaling, was proposed here to account for regulation of AChE in TF-1 cell. A binding sequence of GATA-1 was identified in ACHE gene promoter, which was further confirmed by chromatin immunoprecipitation (ChIP) assay. Over-expression of GATA-1 in TF-1 cultures induced AChE expression, as well as activity of ACHE promoter tagged with luciferase gene (pAChE-Luc). The deletion of GATA-1 sequence on the ACHE promoter, pAChE_ΔGATA-1 -Luc, reduced the promoter activity during erythroblastic differentiation. On the contrary, the knock-down of AChE in TF-1 cultures could lead to a reduction in EPO-induced expression of erythrocytic proteins. These findings indicated specific regulation of AChE during maturation of erythroblast, which provided an insight into elucidating possible mechanisms in regulating erythropoiesis.

Experimental study on the regulation of the cholinergic pathway in renal macrophages by microRNA-132 to alleviate inflammatory response

MicroRNA-132 (miR-132) is correlated with inflammatory response regulation, although its effect on acute kidney injury to provide protection against hemorrhagic shock remains currently unknown. AChE in macrophages of the kidney subjected under hemorrhagic shock is presumed to be regulated by miR-132 after its transcription to alleviate the inflammatory response accordingly. Antagonists such as acetylcholine (Ach) (concentration 10−4mol/L) and galanthamine (Gal) (concentration 10μmol/L) were added into separate groups 1 hour after the macrophages in the kidney were isolated and cultured to induce injury under oxygen and glucose deprivation (OGD) and then cultured for 24 hours. To analyze the effect of miR-132, we placed the renal epithelial cells transfected with miR-132 plasmids with stable expression over the renal macrophages to create a double cell culture system. The expression levels of inflammatory factors and apoptosis under OGD were significantly higher in renal macrophages than in other experimental groups. Moreover, the expression of miR-132 in macrophages of the double cell culture system showing stable expression of miR-132 increased, whereas that of several inflammatory factors was significantly inhibited. The expression levels of AChE mRNA and protein in the macrophages significantly decreased. The cholinergic antiinflammatory pathway in renal macrophages is regulated by miR-132 via inhibition of the hydrolytic activity of cholinesterase to alleviate inflammatory response, which may play a role in the prevention and treatment of kidney injury caused by hemorrhagic shock.

α7 nicotinic acetylcholine receptor signaling modulates the inflammatory phenotype of fetal brain microglia: first evidence of interference by iron homeostasis

Neuroinflammation in utero may result in life-long neurological disabilities. Microglia play a pivotal role, but the mechanisms are poorly understood. No early postnatal treatment strategies exist to enhance neuroprotective potential of microglia. We hypothesized that agonism on α7 nicotinic acetylcholine receptor (α7nAChR) in fetal microglia will augment their neuroprotective transcriptome profile, while the antagonistic stimulation of α7nAChR will achieve the opposite. Using an in vivo - in vitro model of developmental programming of neuroinflammation induced by lipopolysaccharide (LPS), we validated this hypothesis in primary fetal sheep microglia cultures re-exposed to LPS in presence of a selective α7nAChR agonist or antagonist. Our RNAseq and protein level findings show that a pro-inflammatory microglial phenotype acquired in vitro by LPS stimulation is reversed with α7nAChR agonistic stimulation. Conversely, antagonistic α7nAChR stimulation potentiates the pro-inflammatory microglial phenotype. Surprisingly, under conditions of LPS double-hit an interference of a postulated α7nAChR - ferroportin signaling pathway may impede this mechanism. These results suggest a therapeutic potential of α7nAChR agonists in early re-programming of microglia in neonates exposed to in utero inflammation via an endogenous cerebral cholinergic anti-inflammatory pathway. Future studies will assess the role of interactions between inflammation-triggered microglial iron sequestering and α7nAChR signaling in neurodevelopment.

The Stress-Responding miR-132-3p Shows Evolutionarily Conserved Pathway Interactions

MicroRNAs (miRNAs) are small non-coding RNA chains that can each interact with the 3′-untranslated region of multiple target transcripts in various organisms, humans included. MiRNAs tune entire biological pathways, spanning stress reactions, by regulating the stability and/or translation of their targets. MiRNA genes are often subject to co-evolutionary changes together with their target transcripts, which may be reflected by differences between paralog mouse and primate miRNA/mRNA pairs. However, whether such evolution occurred in stress-related miRNAs remained largely unknown. Here, we report that the stress-induced evolutionarily conserved miR-132-3p, its target transcripts and its regulated pathways provide an intriguing example to exceptionally robust conservation. Mice and human miR-132-3p share six experimentally validated targets and 18 predicted targets with a common miRNA response element. Enrichment analysis and mining in-house and web-available experimental data identified co-regulation by miR-132 in mice and humans of stress-related, inflammatory, metabolic, and neuronal growth pathways. Our findings demonstrate pan-mammalian preservation of miR-132′s neuronal roles, and call for further exploring the corresponding stress-related implications.