LncRNA MEG3 Reduces Hippocampal Neuron Apoptosis via the PI3K/AKT/mTOR Pathway in a Rat Model of Temporal Lobe Epilepsy

Exploring ncRNAs in epilepsy: From oxidative stress regulation to therapy

Epilepsy is a prevalent neurological illness which is linked with high worldwide burdens. Oxidative stress (OS) is recognized to be among the contributors that trigger the advancement of epilepsy, affecting neuronal excitability and synaptic transmission. Various types of non-coding RNAs (ncRNAs) are known to serve vital functions in many disease mechanisms, including epilepsy. The current review sought to understand better the mechanisms through which these ncRNAs regulate epilepsy's OS-related pathways. We investigated the functions of microRNAs in controlling gene expression at the post-translatory stage and their involvement in OS and neuroinflammation. We also looked at the different regulatory roles of long ncRNAs, including molecular scaffolding, enhancer, and transcriptional activator, during OS. Circular RNAs and their capability to act as miRNA decoys and their consequential impact on epilepsy development were also explored. Our review aimed to improve the current understanding of novel therapies for epilepsy based on the role of ncRNAs in OS pathways. We also demonstrated the roles of ncRNAs in epilepsy treatment and diagnosis, explaining that these molecules play vital roles that could be used in therapy as biomarkers.

Knockout of the longevity gene Klotho perturbs aging and Alzheimer's disease-linked brain microRNAs and tRNA fragments

Overexpression of the longevity gene Klotho prolongs lifespan, while its knockout shortens lifespan and impairs cognition via perturbation of myelination and synapse formation. However, comprehensive analysis of Klotho knockout effects on mammalian brain transcriptomics is lacking. Here, we report that Klotho knockout alters the levels of aging- and cognition related mRNAs, long non-coding RNAs, microRNAs and tRNA fragments. These include altered neuronal and glial regulators in murine models of aging and Alzheimer's disease and in human Alzheimer's disease post-mortem brains. We further demonstrate interaction of the knockout-elevated tRNA fragments with the spliceosome, possibly affecting RNA processing. Last, we present cell type-specific short RNA-seq datasets from FACS-sorted neurons and microglia of live human brain tissue demonstrating in-depth cell-type association of Klotho knockout-perturbed microRNAs. Together, our findings reveal multiple RNA transcripts in both neurons and glia from murine and human brain that are perturbed in Klotho deficiency and are aging- and neurodegeneration-related.

NLRP3 Inflammasome’s Activation in Acute and Chronic Brain Diseases—An Update on Pathogenetic Mechanisms and Therapeutic Perspectives with Respect to Other Inflammasomes

Increasingly prevalent acute and chronic human brain diseases are scourges for the elderly. Besides the lack of therapies, these ailments share a neuroinflammation that is triggered/sustained by different innate immunity-related protein oligomers called inflammasomes. Relevant neuroinflammation players such as microglia/monocytes typically exhibit a strong NLRP3 inflammasome activation. Hence the idea that NLRP3 suppression might solve neurodegenerative ailments. Here we review the recent Literature about this topic. First, we update conditions and mechanisms, including RNAs, extracellular vesicles/exosomes, endogenous compounds, and ethnic/pharmacological agents/extracts regulating NLRP3 function. Second, we pinpoint NLRP3-activating mechanisms and known NLRP3 inhibition effects in acute (ischemia, stroke, hemorrhage), chronic (Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, MS, ALS), and virus-induced (Zika, SARS-CoV-2, and others) human brain diseases. The available data show that (i) disease-specific divergent mechanisms activate the (mainly animal) brains NLRP3; (ii) no evidence proves that NLRP3 inhibition modifies human brain diseases (yet ad hoc trials are ongoing); and (iii) no findings exclude that concurrently activated other-than-NLRP3 inflammasomes might functionally replace the inhibited NLRP3. Finally, we highlight that among the causes of the persistent lack of therapies are the species difference problem in disease models and a preference for symptomatic over etiologic therapeutic approaches. Therefore, we posit that human neural cell-based disease models could drive etiological, pathogenetic, and therapeutic advances, including NLRP3’s and other inflammasomes’ regulation, while minimizing failure risks in candidate drug trials.

Single-nucleus RNA sequencing unveils critical regulators in various hippocampal neurons for anti-N-methyl-D-aspartate receptor encephalitis

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a neuropsychiatric disease with variable clinical manifestations caused by NMDAR autoantibody. The underlying molecular underpinnings of this disease are rarely characterized on a genomic scale. Anti-NMDAR encephalitis mainly affects the hippocampus, however, its effect on gene expression in hippocampal neurons is unclear at present. Here, we construct the active and passive immunization mouse models of anti-NMDAR encephalitis, and use single-nucleus RNA sequencing to investigate the diverse expression profile of neuronal populations isolated from different hippocampal regions. Dramatic changes in cell proportions and differentially expressed genes were observed in excitatory neurons of the dentate gyrus (DG) subregion. In addition, we found that ATP metabolism and biosynthetic regulators related genes in excitatory neurons of DG subregion were significantly affected. Kcnq1ot1 in inhibitory neurons and Meg3 in interneurons also changed. Notably, the latter two molecules exhibited opposite changes in different models. Therefore, the above genes were used as potential targets for further research on the pathological process of anti-NMDAR encephalitis. These data involve various hippocampal neurons, which delineate a framework for understanding the hippocampal neuronal circuit and the potential molecular mechanisms of anti-NMDAR encephalitis.

Evaluation of the Antioxidant Activity of Levetiracetam in a Temporal Lobe Epilepsy Model

Epilepsy is a neurological disorder in which it has been shown that the presence of oxidative stress (OS) is implicated in epileptogenesis. The literature has shown that some antiseizure drugs (ASD) have neuroprotective properties. Levetiracetam (LEV) is a drug commonly used as an ASD, and in some studies, it has been found to possess antioxidant properties. Because the antioxidant effects of LEV have not been demonstrated in the chronic phase of epilepsy, the objective of this study was to evaluate, for the first time, the effects of LEV on the oxidant–antioxidant status in the hippocampus of rats with temporal lobe epilepsy (TLE). The in vitro scavenging capacity of LEV was evaluated. LEV administration in rats with TLE significantly increased superoxide dismutase (SOD) activity, increased catalase (CAT) activity, but did not change glutathione peroxidase (GPx) activity, and significantly decreased glutathione reductase (GR) activity in comparison with epileptic rats. LEV administration in rats with TLE significantly reduced hydrogen peroxide (H2O2) levels but did not change lipoperoxidation and carbonylated protein levels in comparison with epileptic rats. In addition, LEV showed in vitro scavenging activity against hydroxyl radical (HO•). LEV showed significant antioxidant effects in relation to restoring the redox balance in the hippocampus of rats with TLE. In vitro, LEV demonstrated direct antioxidant activity against HO•.

LncRNA PVT1 Promotes Neuronal Cell Apoptosis and Neuroinflammation by Regulating miR-488-3p/FOXD3/SCN2A Axis in Epilepsy

It is vital to understand the mechanism of epilepsy onset and development. Dysregulated lncRNAs are closely associated with epilepsy. Our work probed the role of lncRNA PVT1/miR-488-3p/FOXD3/SCN2A axis in epilepsy. The mRNA and protein expressions were assessed using qRT-PCR and western blot. MTT assay and TUNEL staining were conducted to assess cell viability and apoptosis, respectively. TNFα, IL-1β and IL-6 levels were analyzed using ELISA. LDH level was tested by Assay Kit. The binding relationship between PVT1, miR-488-3p and FOXD3 were verified using dual luciferase reporter gene assay. The epilepsy model of rats was established by lithium-pilocarpine injection. Nissl staining was performed to evaluate neuronal damage. PVT1 was markedly upregulated in epilepsy model cells. Knockdown of PVT1 increased the viability, while repressed the apoptosis and inflammatory cytokines secretion as well as LDH level in epilepsy cell model. MiR-488-3p alleviated neuronal injury and neuroinflammation in model cells. MiR-488-3p functioned as the direct target of PVT1, and its inhibition neutralized the effects of PVT1 silencing on neuronal cell injury and neuroinflammation in model cells. Furthermore, miR-488-3p inhibited neuronal cell injury and neuroinflammation in model cells by regulating FOXD3/SCN2A pathway. Finally, animal experiments proved that PVT1 promoted epilepsy-induced neuronal cell injury and neuroinflammation by regulating miR-488-3p-mediated FOXD3/SCN2A pathway. PVT1 promoted neuronal cell injury and inflammatory response in epilepsy via inhibiting miR-488-3p and further regulating FOXD3/SCN2A pathway.

Sesamin alleviates defects in seizure, behavioral symptoms, and hippocampus electroencephalogram in a pentylenetetrazol rat model

Objectives

Seizure is a prevalent disorder reflected by powerful and sudden activity of neural networks in the brain that leads to tonic-clonic attacks. These signs may be due to an increase in excitatory/inhibitory neurotransmitters ratio. So, the current experiment aimed to examine the seizure and neurobehavioral parameters, as well as the hippocampus local electroencephalogram (EEG) after seizure with and without sesamin pretreatment.

Materials and Methods

Sesamin (15, 30, and 60 mg/kg/5 ml, intraperitoneal or IP, vehicle: dimethyl sulfoxide or DMSO, for 3 days) was administrated before pentylenetetrazol (PTZ) (60 mg/kg/10 ml, IP, vehicle: saline), which induces acute seizure in adult male Wistar rats (230 ± 20 g, six weeks old). Different phases of seizures (score, latency, duration, and frequency), behavioral parameters (passive avoidance memory, anxiety, and locomotor activity), and hippocampus local EEG were evaluated after the injections. At the end of the experiments, oxidative stress markers plus gene expression of phosphoinositide 3-kinase/protein kinase B or PI3K/Akt mRNA were measured in the hippocampus.

Results

Pretreatment with sesamin (30 mg/kg) could significantly decrease seizure scores and oxidative stress in the hippocampus. PTZ injection induced EEG deficits and neurobehavioral impairments which were significantly decreased by sesamin, especially in Beta, Theta, and delta EEG waves. Also, the expression of PI3K/Akt significantly increased in the sesamin (30 mg/kg) group in comparison with the PTZ group.

Conclusion

Sesamin could prevent seizure attacks and neurobehavioral and EEG deficits induced by pentylenetetrazol, probably through the PI3K/Akt signaling pathway.

Long-term LDR exposure may induce cognitive impairments: A possible association through targeting gut microbiota-gut-brain axis

Environmental and occupational low-dose radiation (LDR) exposure may be harmful for health but the previous reports regarding effect of LDR on cognition are contradictory. Here we investigated the effect of long-term LDR exposure on cognition. In this study, male Balb/c mice' cognitive functions were tested at 15 weeks after being exposed to 0.5 Gy LDR in 10 fractions at each dose of 0.05 Gy. The results demonstrated that long-term LDR exposure increases escape latency and the time spent in finding exits in mice compared with non LDR exposure. Meanwhile, the inflammation-related proteins including NFκB and p38 also increased. Lipopolysaccharide (LPS) increased and short-chain fatty acid (SCFA) levels decreased following long term LDR exposure. Treatment with microbiota-derived LPS and SCFAs reversed these effects in mice. Furthermore, the gut barrier integrity was damaged in a time-dependent manner with the decreased expression of intestinal epithelial-related biomarkers such as ZO-1 and occludin. Mechanistically, long after exposure to LDR, increased LPS levels may cause cognitive impairment through the regulation of Akt/mTOR signaling in the mouse hippocampus. These findings provide new insight into the clinical applications of LDR and suggest that the gut microbiota-plasma LPS and SCFAs-brain axis may underlie long-term LDR-induced cognition effects.

Role of lncRNAs and circRNAs in epilepsy

Epilepsy is a chronic disorder of with a high prevalence and extensive health burden in almost all age groups of the population. This condition is resulted from disturbance in the balance between excitatory and inhibitory factors in the brain. Genetic elements that affect synaptic connectivity, receptors functions or ion channels have been shown to predispose individuals to the epilepsy. More recently, a body of evidence points to the role of non-coding part of the transcriptome in the pathology of epilepsy. Expression levels of NEAT1, H19, PVT1, ILF3-AS1, GAS5, ZFAS1, UCA1, MALAT1 and SNHG1 have been changed in epileptic patients or animal models of epilepsy. Moreover, circ_ANKMY2, circRNA-0067835 and circHivep2 are among circRNAs which are involved in the pathogenesis of epilepsy. Although the mechanistical impact of these transcripts in the pathogenesis of epilepsy has not been fully explored, disturbances in neuron plasticity, apoptosis or differentiation might be implicated in this process. Expression levels of lncRNAs can be used for discrimination of epileptic patients from normal controls or refractory patients from non-refractory ones. JAK/STAT, Wnt, PI3K/AKT and NF-κB signaling pathways are among the regulated pathways by lncRNAs in the context of epilepsy. In the present review, we summarize the role of lncRNAs and circRNAs in the pathogenesis of epilepsy.

LncRNA MEG3: Potential stock for precision treatment of cardiovascular diseases

The prevalence and mortality rates of cardiovascular diseases are increasing, and new treatment strategies are urgently needed. From the perspective of basic pathogenesis, the occurrence and development of cardiovascular diseases are related to inflammation, apoptosis, fibrosis and autophagy of cardiomyocytes, endothelial cells and other related cells. The involvement of maternally expressed gene 3 (MEG3) in human disease processes has been increasingly reported. P53 and PI3K/Akt are important pathways by which MEG3 participates in regulating cell apoptosis. MEG3 directly or competitively binds with miRNA to participate in apoptosis, inflammation, oxidative stress, endoplasmic reticulum stress, EMT and other processes. LncRNA MEG3 is mainly involved in malignant tumors, metabolic diseases, immune system diseases, cardiovascular and cerebrovascular diseases, etc., LncRNA MEG3 has a variety of pathological effects in cardiomyocytes, fibroblasts and endothelial cells and has great clinical application potential in the prevention and treatment of AS, MIRI, hypertension and HF. This paper will review the research progress of MEG3 in the aspects of mechanism of action, other systemic diseases and cardiovascular diseases, and point out its great potential in the prevention and treatment of cardiovascular diseases. lncRNAs also play a role in endothelial cells. In addition, lncRNA MEG3 has shown biomarker value, prognostic value and therapeutic response measurement in tumor diseases. We boldly speculate that MEG3 will play a role in the emerging discipline of tumor heart disease.

Long non-coding RNAs: Potential therapeutic targets for epilepsy

Epilepsy is a common and disastrous neurological disorder characterized by abnormal firing of neurons in the brain, affecting about 70 million people worldwide. Long non-coding RNAs (LncRNAs) are a class of RNAs longer than 200 nucleotides without the capacity of protein coding, but they participate in a wide variety of pathophysiological processes. Alternated abundance and diversity of LncRNAs have been found in epilepsy patients and animal or cell models, suggesting a potential role of LncRNAs in epileptogenesis. This review will introduce the structure and function of LncRNAs, summarize the role of LncRNAs in the pathogenesis of epilepsy, especially its linkage with neuroinflammation, apoptosis, and transmitter balance, which will throw light on the molecular mechanism of epileptogenesis, and accelerate the clinical implementation of LncRNAs as a potential therapeutic target for treatment of epilepsy.

LncRNA MEG3 activates CDH2 expression by recruitment of EP300 in valproic acid-induced autism spectrum disorder

LncRNAs partake in the biological processes contributing to development of autism spectrum disorder (ASD). The aim of the present study is to investigate the effects of lncRNA maternally expressed gene 3 (MEG3) on viability and apoptosis of hippocampal neurons from ASD rats. Rats with ASD were induced using valproic acid (VPA) with normal saline (NS) as control. We performed microarray analysis on hippocampal tissues of NS rats and ASD rats to screen the differentially expressed lncRNAs. MEG3 loss in rats alleviated the impairment of learning and memory abilities induced by VPA, and promoted neuronal viability and inhibited apoptosis. MEG3 could recruit the transcription factor E1A binding protein p300 (EP300) in the nucleus and promote the cadherin 2 (CDH2) expression. CDH2 depletion in rats ameliorated the impairment of learning and memory capacities in ASD rats. After upregulation of CDH2 in neurons with sh-MEG3, we found diminished viability and increased apoptosis in hippocampal neurons of ASD rats. Taken together, MEG3 supports activation of CDH2 via EP300, thus repressing the viability of hippocampal neurons. Therefore, MEG3 upregulation may be partially responsible for the pathogenesis of ASD.

Regulation of Oxidative Stress by Long Non-coding RNAs in Central Nervous System Disorders

Central nervous system (CNS) disorders, such as ischemic stroke, Alzheimer’s disease, Parkinson’s disease, spinal cord injury, glioma, and epilepsy, involve oxidative stress and neuronal apoptosis, often leading to long-term disability or death. Emerging studies suggest that oxidative stress may induce epigenetic modifications that contribute to CNS disorders. Non-coding RNAs are epigenetic regulators involved in CNS disorders and have attracted extensive attention. Long non-coding RNAs (lncRNAs) are non-coding RNAs more than 200 nucleotides long and have no protein-coding function. However, these molecules exert regulatory functions at the transcriptional, post-transcriptional, and epigenetic levels. However, the major role of lncRNAs in the pathophysiology of CNS disorders, especially related to oxidative stress, remains unclear. Here, we review the molecular functions of lncRNAs in oxidative stress and highlight lncRNAs that exert positive or negative roles in oxidation/antioxidant systems. This review provides novel insights into the therapeutic potential of lncRNAs that mediate oxidative stress in CNS disorders.

Significant reduction of long non-coding RNAs expression in bipolar disorder

Long non-coding RNAs (lncRNAs) have been recently emerged as critical modulators of oxidative stress pathway. Likewise, rising evidence currently highlights dysfunction of oxidative stress pathways in bipolar disorder (BD) patients.In the current study, we evaluated the expression levels of H19, SCAL1 (LUCAT1), RMST, MEG3 and MT1DP lncRNAs in the PBMC from 50 patients with BD and 50 control subjects (male/female ratio in each group: 70%/30%). Expression levels of SCAL1, RMST and MEG3 but not H19 and MT1DP were considerably decreased in BD patients compared with healthy individuals. Such significant decrease in the expression of MEG3, RMST and SCAL1 was only reported in male BD patients compared with male controls. Substantial pairwise correlations were observed between expression levels of these lncRNAs in BD subjects. The area under curve values for RMST, MEG3 and SCAL1 were 0.70, 0.63 and 0.61 respectively. On the basis of this finding, RMST had the best efficiency in the discrimination of disease status between BD patients and controls. Taken together, the current results suggest a role for MEG3, RMST and SCAL1 lncRNAs in the pathogenesis of BD. In addition, peripheral expression levels of these lncRNAs might serve as potential peripheral markers for BD.

Non-Coding RNAs: New Biomarkers and Therapeutic Targets for Temporal Lobe Epilepsy

Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy; it is considered a network disorder associated with structural changes. Incomplete knowledge of the pathological changes in TLE complicates a therapeutic approach; indeed, 30 to 50% of patients with TLE are refractory to drug treatment. Non-coding RNAs (ncRNAs), acting as epigenetic factors, participate in the regulation of the pathophysiological processes of epilepsy and are dysregulated during epileptogenesis. Abnormal expression of ncRNA is observed in patients with epilepsy and in animal models of epilepsy. Furthermore, ncRNAs could also be used as biomarkers for the diagnosis and prognosis of treatment response in epilepsy. In summary, ncRNAs can represent important mechanisms and targets for the modulation of brain excitability and can provide information on pathomechanisms, biomarkers and novel therapies for epilepsy. In this review, we summarize the latest research advances concerning mainly molecular mechanisms, regulated by ncRNA, such as synaptic plasticity, inflammation and apoptosis, already associated with the pathogenesis of TLE. Moreover, we discuss the role of ncRNAs, such as microRNAs, long non-coding RNAs and circular RNAs, in the pathophysiology of epilepsy, highlighting their use as potential biomarkers for future therapeutic approaches.

Study of Neuronal Apoptosis ceRNA Network in Hippocampal Sclerosis of Human Temporal Lobe Epilepsy by RNA-Seq

Hippocampal sclerosis (HS) is one of the most common pathological type of intractable temporal lobe epilepsy (TLE), often characterized by hippocampal atrophy, neuronal apoptosis, and gliogenesis. However, the molecular mechanisms of neuronal apoptosis in patients with HS are still not fully understood. We therefore conducted a pilot study focusing on the neuronal apoptosis ceRNA network in the sclerotic hippocampus of intractable TLE patients. In this research, RNA sequencing (RNA-seq) was utilized to quantify the expression levels of lncRNAs, miRNAs, and mRNAs in TLE patients with HS (HS-TLE) and without HS (non-HS-TLE), and reverse transcription-quantitative PCR (qRT-PCR). The interactions of differential expression (DE) lncRNAs-miRNAs or DEmiRNAs-mRNAs were integrated by StarBase v3.0, and visualized using Cytoscape. Subsequently, we annotate the functions of lncRNA-associated competitive endogenous RNA (ceRNA) network through analysis of their interactions with mRNAs. RNA-seq analyses showed 381 lncRNAs, 42 miRNAs, and 457 mRNAs were dysregulated expression in HS-TLE compared to non-HS-TLE. According to the ceRNA hypothesis, 5 HS-specific ceRNA network were constructed. Among them, the core ceRNA regulatory network involved in neuronal apoptosis was constituted by 10 DElncRNAs (CDKN2B-AS1, MEG3, UBA6-AS1, etc.), 7 DEmiRNAs (hsa-miR-155-5p, hsa-miR-195-5p, hsa-miR-200c-3p, etc.), and 3 DEmRNAs (SCN2A, DYRK2, and MAPK8), which belonging to apoptotic and epileptic terms. Our findings established the first ceRNA network of lncRNA-mediated neuronal apoptosis in HS-TLE based on transcriptome sequencing, which provide a new perspective on the disease pathogenesis and precise treatments of HS.

Pharmacological modulation of cytokines correlating neuroinflammatory cascades in epileptogenesis

Epileptic seizure-induced brain injuries include activation of neuroimmune response with activation of microglia, astrocytes cells releasing neurotoxic inflammatory mediators underlies the pathophysiology of epilepsy. A wide spectrum of neuroinflammatory pathways is involved in neurodegeneration along with elevated levels of inflammatory mediators indicating the neuroinflammation in the epileptic brain. Therefore, the neuroimmune response is commonly observed in the epileptic brain, indicating elevated cytokine levels, providing an understanding of the neuroinflammatory mechanism contributing to seizures recurrence. Clinical and experimental-based evidence suggested the elevated levels of cytokines responsible for neuronal excitation and blood-brain barrier (BBB) dysfunctioning causing the drug resistance in epilepsy. Therefore, the understanding of the pathogenesis of neuroinflammation in epilepsy, including migration of microglial cells releasing the inflammatory cytokines indicating the correlation of elevated levels of inflammatory mediators (interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) triggering the generation or recurrence of seizures. The current review summarized the knowledge regarding elevated inflammatory mediators as immunomodulatory response correlating multiple neuroinflammatory NF-kB, RIPK, MAPK, ERK, JNK, JAK-STAT signaling cascades in epileptogenesis. Further selective targeting of inflammatory mediators provides beneficial therapeutic strategies for epilepsy.

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.

DUSP1 regulates hippocampal damage in epilepsy rats via ERK1/2 pathway

OBJECTIVE

To investigate the effects of DUSP1 on the hippocampal injury of young rats with epilepsy (EP) through mediating ERK1/2 signaling pathway.

METHODS

Young SD rats were selected and divided into Control, EP, EP + LV-GFP, EP + LV-DUSP1, EP + LV-siDUSP1, and EP + LV-siDUSP1 + U0126 groups. Morris Water Maze Test was used to detect the spatial learning and memory. Nissl staining and TUNEL staining were conducted and the inflammatory factors and oxidative stress-related indicators were also measured. Western blotting was utilized to detect the expression of DUSP1 and ERK1/2 pathway. EP cell model was constructed in vitro to verify the in vivo results.

RESULTS

Compared with Control group, young rats in EP group had decreased spatial learning and memory abilities and increased apoptotic rate and decreased number of Nissl positive cells. Besides, the up-regulated levels in inflammatory factors (IL-1β, IL-6), MDA content, and p-ERK1/2/ERK1/2 protein expression, as well as the down-regulated levels in DUSP1 protein expression and SOD content were also observed in EP rats. The EP rats treated with LV-DUSP1 showed obvious improvements regarding the above indicators, while those treated with LV-siDUSP1 had aggravated injury. But the effect of LV-siDUSP1 can be reversed by the treatment with ERK1/2 pathway inhibitor U0126. Further in vitro investigation verified the in vivo results.

CONCLUSION

DUSP1 may ameliorate the oxidative stress and inflammatory injury, as well as improve spatial learning and memory abilities via inhibiting ERK1/2 pathway, eventually playing protective roles in hippocampal injury of young rats with EP.

Regulation of glial cell-derived neurotrophic factor in sevoflurane-induced neuronal apoptosis by long non-coding RNA CDKN2B-AS1 as a ceRNA to adsorb miR-133

OBJECTIVE

To investigate the regulatory mechanism of sevoflurane-induced neuronal apoptosis through analyzing the expression of glial cell-derived neurotrophic factor (GDNF) mediated by miR-133, sponged by long non-coding RNA (lncRNA) CDKN2B-AS1.

METHODS

An in vitro cell injury model was established by using different concentrations of sevoflurane and primary hippocampal neurons. Cell proliferation was detected by Cell Counting Kit-8 (CCK-8); caspase-3 and caspase-9 activities were detected by colorimetry, and apoptotic cells were determined by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Fluorescence in situ hybridization (FISH) analysis was used to detect localized expression of CDKN2B antisense RNA 1 (CDKN2B-AS1), and dual-luciferase reporter assay was employed to verify the correlation of CDKN2B-AS1 and miR-133, and of miR-133 and GDNF. The expression of CDKN2B-AS1, miR-133, and GDNF mRNA in the cell injury model were measured by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Western blot was utilized to detect the expression of GDNF protein in the cell injury model.

RESULTS

In the cell injury model, CDKN2B-AS1 was highly expressed in the cytoplasm, and CDKN2B-AS1 and GDNF were downregulated and miR-133 was upregulated as detected by qRT-PCR (all P<0.05). The connections between CDKN2B-AS1 and miR-133, and between miR-133 and GDNF were confirmed. That is, CDKN2B-AS1 regulated the expression of GDNF by adsorbing miR-133 (all P<0.05). In cells treated with sevoflurane, overexpression of CDKN2B-AS1 could inhibit caspase-3 and caspase-9 activities and the degree of apoptosis. miR-133 could partially alleviate the effect of overexpressing CDKN2B-AS1 on cells, and si-GDNF the effect of miR-133 inhibitor (all P<0.05).

CONCLUSION

lncRNA CDKN2B-AS1 can up-regulate the expression of GDNF, inhibit neuronal apoptosis, and ease the toxic effect of sevoflurane on neural cells by acting as a sponge to adsorb miR-133.

Protective effect of Houttuynia cordata extract on propofol-induced injury of rat hippocampal neurons by regulating PI3K/Akt and Toll-like receptor 4/NF-κB signaling pathway

OBJECTIVE

This study was to detect the protective effects of Houttuynia cordata extract on the damage induced by propofol in hippocampal neuron of rats.

METHODS

Propofol-induced neuron injury model and H. cordata extract administration were conducted. Immunofluorescence and immunoblot were conducted for the effect of H. cordata extract on neuronal activity and inflammation were detected in this model.

RESULTS

H. cordata extracts increased neuronal activity, and reduced propofol-induced neuronal inflammation levels. H. cordata extract also reduced propofol-induced neuronal apoptosis. Mechanically, we noticed H. cordata extract activated phosphoinositide 3-kinase/AKT pathway and suppressed Toll-like receptor 4/nuclear factor kappaB pathway, therefore protected propofol-induced injury of rat hippocampal neurons.

CONCLUSION

Our findings provide references for anesthetic use in infants and young children.

Lithium and Atypical Antipsychotics: The Possible WNT/β Pathway Target in Glaucoma

Glaucoma is a progressive neurodegenerative disease that represents the major cause of irreversible blindness. Recent findings have shown which oxidative stress, inflammation, and glutamatergic pathway have main roles in the causes of glaucoma. Lithium is the major commonly used drug for the therapy of chronic mental illness. Lithium therapeutic mechanisms remain complex, including several pathways and gene expression, such as neurotransmitter and receptors, circadian modulation, ion transport, and signal transduction processes. Recent studies have shown that the benefits of lithium extend beyond just the therapy of mood. Neuroprotection against excitotoxicity or brain damages are other actions of lithium. Moreover, recent findings have investigated the role of lithium in glaucoma. The combination of lithium and atypical antipsychotics (AAPs) has been the main common choice for the treatment of bipolar disorder. Due to the possible side effects gradually introduced in therapy. Currently, no studies have focused on the possible actions of AAPs in glaucoma. Recent studies have shown a down regulation of the WNT/β-catenin pathway in glaucoma, associated with the overactivation of the GSK-3β signaling. The WNT/β-catenin pathway is mainly associated with oxidative stress, inflammation and glutamatergic pathway. Lithium is correlated with upregulation the WNT/β-catenin pathway and downregulation of the GSK-3β activity. Thus, this review focuses on the possible actions of lithium and AAPs, as possible therapeutic strategies, on glaucoma and some of the presumed mechanisms by which these drugs provide their possible benefit properties through the WNT/β-catenin pathway.