Upregulation of miR-215 exerts neuroprotection effects against ischemic injury via negative regulation of Act1/IL-17RA signaling

Focal ischemic stroke modifies microglia-derived exosomal miRNAs: potential role of mir-212-5p in neuronal protection and functional recovery

BACKGROUND

Ischemic stroke is a severe type of stroke with high disability and mortality rates. In recent years, microglial exosome-derived miRNAs have been shown to be promising candidates for the treatment of ischemic brain injury and exert neuroprotective effects. Mechanisms underlying miRNA dysregulation in ischemic stroke are still being explored. Here, we aimed to verify whether miRNAs derived from exosomes exert effects on functional recovery.

METHODS

MiR-212-5p agomir was employed to upregulate miR-212-5p expression in a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) as well as an oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro. Western blot analysis, qRT-PCR and immunofluorescence staining and other methods were applied to explore the underlying mechanisms of action of miR-212-5p.

RESULTS

The results of our study found that intervention with miR-212-5p agomir effectively decreased infarct volume and restored motor function in MCAO/R rats. Mechanistically, miR-212-5p agomir significantly reduced the expression of PlexinA2 (PLXNA2). Additionally, the results obtained in vitro were similar to those achieved in vivo.

CONCLUSION

In conclusion, the present study indicated that PLXNA2 may be a target gene of miR-212-5p, and miR-212-5p has great potential as a target for the treatment and diagnosis of ischemic stroke.

Bisphenol A aggravate selenium deficiency-induced apoptosis via miR-215-3p/Dio1 to activate ROS/PI3K/AKT pathway in chicken arterial

Both bisphenol A (BPA) and selenium (Se) deficiency can affect the expression of microRNAs (miRNAs), which can specifically regulate its target mRNA and induce apoptosis, and play a significant role in cardiovascular injury diseases. To explore the mechanism of apoptosis induced by BPA and Se deficiency in chicken arterial endothelial tissue and the role of miRNAs in this process, the model of BPA exposure/Se deficiency in chicken and PAEC cells have been employed. The targeting relationship between miR-215-3p and iodothyronine deiodinase 1 (Dio1) in PAEC was verified by double luciferase gene report. The level of miR-215-3p was detected by qRT-PCR. The oxidative stress level of arterial endothelial cells was detected by oxidative stress kit and DCFH-DA probe method. The PI3K/AKT pathway, mitochondrial dynamics, and apoptosis-related genes were detected by qRT-PCR and western blot. The mitochondrial ATP level and nitric oxide synthases (NOSs) level were detected with the kit. TUNEL, acridine orange/ethidium bromide, and flow cytometry were used to detect the level of apoptosis. The results showed that BPA exposure and Se deficiency led to overexpression of miR-215-3p, aggravated oxidative stress, inhibited activation of PI3K/AKT pathway, promoted mitochondrial division, increased expression of apoptosis related genes, and finally led to apoptosis of chicken arterial endothelial cells. We also established knockdown/overexpression models of miR-215-3p and Dio1 in vitro, and found that overexpression of miR-215-3p and knockout of Dio1 can induce apoptosis. Interestingly, miR-215-3p-Inhibitor and N-acetyl- l-cysteine (NAC) partially prevented apoptosis caused by BPA exposure and Se deficiency, and LY294002 aggravated apoptosis. These results suggest that BPA exposure aggravates the apoptosis of Se deficient arterial endothelial cells in chickens by regulating the ROS/PI3K/AKT pathway activated by miR-215-3p/Dio1. The miR-215-3p/Dio1 axis provides a new way to understand the toxic mechanism of BPA exposure and Se deficiency, and reveals a new regulatory model of apoptosis damage in vascular diseases.

Some miRNA expressions and their targets in ischemic stroke

Ischemic stroke (IS) is a global health challenge leading to life-long disabilities or the deaths of patients. IS is a complex disease where genetic and environmental factors are both concerned with the pathophysiology of the condition. Here, we aimed to investigate various microRNA (miRNA) expressions and their targets in IS. A rapid and accurate diagnosis of acute IS is important to perform appropriate treatment. Therefore, there is a need for a more rapid and simple tool to carry out an acute diagnosis of IS. miRNAs are small RNA molecules serving as precious biomarkers due to their easy detection and stability in blood samples. The present systematic review aimed to summarize previous studies investigating several miRNA expressions and their targets in IS.

γδ T Cell in Cerebral Ischemic Stroke: Characteristic, Immunity-Inflammatory Role, and Therapy

Gamma-delta (γδ) T cells are a small subset of T cells that are reported to have a proinflammatory role in the pathophysiology of cerebral ischemia stroke (CIS). Upon activation by interleukin-1 beta (IL-1β), IL-23 and IL-18, γδ T cells are stimulated to secrete various cytokines, such as IL-17a, IL-21, IL-22, and interferon-gamma (IFN-γ). In addition, they all play a pivotal role in the inflammatory and immune responses in ischemia. Nevertheless, the exact mechanisms responsible for γδ T cell proinflammatory functions remain poorly understood, and more effective therapies targeting at γδ T cells and cytokines they release remain to be explored, particularly in the context of CIS. CIS is the second most common cause of death and the major cause of permanent disability in adults worldwide. In this review, we focus on the neuroinflammatory and immune functions of γδ T cells and related cytokines, intending to understand their roles in CIS, which may be crucial for the development of novel effective clinical applications.

Interleukin-17 and ischaemic stroke

Interleukin-17 (IL-17) is a cytokine family that includes 6 members, IL-17A through IL-17F, most of them are reported to have pro-inflammatory role. Through binding to their receptors (IL-17Rs), IL-17 activates the intracellular signalling pathways to play an important role in autoimmune diseases, including rheumatoid arthritis (RA) and multiple sclerosis (MS). Ischaemic stroke is a complex pathophysiological process mainly caused by regional cerebral ischaemia. Inflammatory factors contribute to the physiological process of stroke that leads to poor prognosis. IL-17 plays a crucial role in promoting inflammatory response and inducing secondary injury in post-stroke. Though immune cells and inflammatory factors have been reported to be involved in the damage of stroke, the functions of IL-17 in this process need to be elucidated. This review focuses on the pathological modulation and the mechanism of IL-17 family in ischaemic stroke and seeking to provide new insights for future therapies.

Principal component analysis of blood microRNA datasets facilitates diagnosis of diverse diseases

Early, ideally pre-symptomatic, recognition of common diseases (e.g., heart disease, cancer, diabetes, Alzheimer’s disease) facilitates early treatment or lifestyle modifications, such as diet and exercise. Sensitive, specific identification of diseases using blood samples would facilitate early recognition. We explored the potential of disease identification in high dimensional blood microRNA (miRNA) datasets using a powerful data reduction method: principal component analysis (PCA). Using Qlucore Omics Explorer (QOE), a dynamic, interactive visualization-guided bioinformatics program with a built-in statistical platform, we analyzed publicly available blood miRNA datasets from the Gene Expression Omnibus (GEO) maintained at the National Center for Biotechnology Information at the National Institutes of Health (NIH). The miRNA expression profiles were generated from real time PCR arrays, microarrays or next generation sequencing of biologic materials (e.g., blood, serum or blood components such as platelets). PCA identified the top three principal components that distinguished cohorts of patients with specific diseases (e.g., heart disease, stroke, hypertension, sepsis, diabetes, specific types of cancer, HIV, hemophilia, subtypes of meningitis, multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer’s disease, mild cognitive impairment, aging, and autism), from healthy subjects. Literature searches verified the functional relevance of the discriminating miRNAs. Our goal is to assemble PCA and heatmap analyses of existing and future blood miRNA datasets into a clinical reference database to facilitate the diagnosis of diseases using routine blood draws.

Upregulation of miR-215 attenuates propofol-induced apoptosis and oxidative stress in developing neurons by targeting LATS2

Background

Propofol is an intravenous anesthetic agent that commonly induces significant neuroapoptosis. MicroRNAs (miRNAs) have been reported to participate in the regulation of propofol exposure-mediated neurotoxicity. MiR-215, as one of miRNAs, was found to regulate nerve cell survival. However, the mechanism through which miRNAs regulate propofol exposure-mediated neurotoxicity is still unclear.

Methods

Real-time PCR was used to detect miR-215 expression level. Cell viability was measured using MTT assay. Cell apoptosis was examined via flow cytometry analysis. ROS, MDA, LDH and SOD levels were assayed through ELISA kits. Dual luciferase reporter assay identified the interaction between miR-215 and large tumor suppressor 2 (LATS2). Protein level was detected using western blot analysis.

Results

MiR-215 expression was downregulated in propofol-treated rat hippocampal neurons. MiR-215 mimics promoted cell viability and reduced apoptosis in propofol-treated neonatal rat hippocampal neuron. MiR-215 mimics also caused inhibition of oxidative stress as evidenced by suppression of ROS, MDA and LDH levels as well as increase of SOD level. In addition, we found that large tumor suppressor 2 (LATS2) is a target of miR-215 and miR-215 mimics decreased LATS2 level in propofol-treated neonatal rat hippocampal neuron. Further, LATS2 overexpression suppressed the effect of miR-215 on propofol-induced apoptosis and oxidative stress in neonatal rat hippocampal neuron.

Conclusion

Taken together, we demonstrate that miR-215 attenuates propofol-induced apoptosis and oxidative stress in neonatal rat hippocampal neuron by targeting LATS2, suggesting that miR-215 may provide a new candidate for the treatment of propofol exposure-induced neurotoxicity.

Do exosomes play role in cardiovascular disease development in hematological malignancy?

Exosomes play a role in the pathogenesis and treatment of malignancies as a double-edged sword. Recently, researchers discussed about two new roles, cardiomyocyte function impairment and cardiovascular disease (CVD) genesis. Data were collected from PUBMED at various time points up to the 2019 academic year. The related key words are listed as following; "Arsenic trioxide", "acute promyelocytic leukemia" and "cardio toxicity" and "molecular pathway" and "biomarker". This study has shown that exosomes secreted substances stimulate angiogenesis and cardiomyocytes repairment; cited process depended on the kinds of released substances. Generally, exosomes may involve in the pathogenesis of CVD; although CVD can prevented by identifying the pathways that induce angiogenesis.

Astragaloside IV Exerts Cognitive Benefits and Promotes Hippocampal Neurogenesis in Stroke Mice by Downregulating Interleukin-17 Expression via Wnt Pathway

Background

Stroke remains a leading cause of adult disability and the demand for stroke rehabilitation services is growing, and Astragaloside IV (As IV), a primary bioactive compound of Radix Astragali : Astragalus mongholicus Bunge (Fabaceae), may be a promising stroke therapy.

Methods

To access the effect of As IV on adult mice after ischemic stroke, a photochemical ischemia model was established on C57BL/6 mice, which were intravenously administered As IV for three consecutive days later. And then the cognitive benefits and hippocampal neurogenesis were evaluated by Morris Water Maze (MWM) test, Golgi staining, and immunohistochemical staining in vivo and in vitro. Furthermore, to find out the underlying mechanism, interleukin-17 (IL-17) knockout (KO) mice were used, through RNA sequence (RNA-seq) analysis and immunohistochemistry. Then the mechanism of neurogenesis promoted by As IV was observed by western blot both in vivo and in vitro. Specifically, As IV, recombinant mouse IL-17A and IL-17F, and Wingless/integrated (Wnt)-expressing virus was administered respectively in neural stem cells (NSCs), and then their diameters and protein expression of Nestin, IL-17, and Wnt pathway relevant protein, were measured in vitro.

Results

Administering As IV resulted in significant amelioration of stroke-induced cognitive deficits. And more hippocampal neurons with normal morphology, significant increments in the length of the apical dendrites, and the density of their spines were observed in As IV-treated mice. Furthermore, the immunohistochemistry staining of DCX/BrdU and Sox2/Nestin showed As IV could promote hippocampal neurogenesis and NSC proliferation after ischemic stroke, as well as in vitro. For the mechanism underlying, IL-17 expression was downregulated significantly by As IV treatment and knocking out IL-17 was associated with nervous regeneration and synapse repair according to the analysis of RNA-seq. Consistent to As IV treatment, knocking out IL-17 showed some promotion on hippocampal neurogenesis and proliferation of NSCs, with activating Wnt pathway after stoke. Finally, in vitro, NSCs’ diameters and protein expression of Nestin, IL-17, and Wnt pathway were regulated by either administering As IV or inhibiting IL-17.

Conclusion

As IV stimulates hippocampal neurogenesis after stroke, thus potentially facilitates brain to remodel and repair by downregulating IL-17 expression via Wnt pathway.

Identification of differentially expressed microRNAs in the skin of experimentally sensitized naturally affected atopic beagles by next-generation sequencing

Canine atopic dermatitis (AD) is a very common inflammatory skin disease, but limited data are available on the genetic characterization (somatic mutations, microarrays, and genome-wide association study (GWAS)) of skin lesions in affected dogs. microRNAs are good biomarkers in inflammatory and neoplastic diseases in people. The aim of this study was to evaluate microRNA expression in the skin of atopic beagles, before and after exposure to Dermatophagoides farinae. Four atopic and four unrelated age-matched healthy beagle dogs were enrolled. Total RNA was extracted from flash-frozen skin biopsies of healthy and atopic dogs. For the atopic dogs, skin biopsies were taken from non-lesional (day 0) and lesional skin (day 28 of weekly environmental challenge with Dermatophagoides farinae). Small RNA libraries were constructed and sequenced. The microRNA sequences were aligned to CanFam3.1 genome. Differential expressed microRNAs were selected on the basis of fold-change and statistical significance (fold-change ≥ 1.5 and p ≤ 0.05 as thresholds. A total of 277 microRNAs were sequenced. One hundred and twenty-one differentially regulated microRNAs were identified between non-lesional and healthy skin. Among these, two were increased amount and 119 were decreased amount. A total of 45 differentially regulated microRNAs between lesional and healthy skin were identified, 44 were decreased amount and one was increased amount. Finally, only two increased amount microRNAs were present in lesional skin when compared with that of non-lesional skin. This is the first study in which dysregulation of microRNAs has been associated with lesional and non-lesional canine AD. Larger studies are needed to understand the role of microRNA in canine AD.

tRNA-derived fragments and microRNAs in the maternal-fetal interface of a mouse maternal-immune-activation autism model

tRNA-derived small fragments (tRFs) and tRNA halves have emerging functions in different biological pathways, such as regulating gene expression, protein translation, retrotransposon activity, transgenerational epigenetic changes and response to environmental stress. However, small RNAs like tRFs and microRNAs in the maternal-fetal interface during gestation have not been studied extensively. Here we investigated the small RNA composition of mouse placenta/decidua, which represents the interface where the mother communicates with the foetus, to determine whether there are specific differences in tRFs and microRNAs during fetal development and in response to maternal immune activation (MIA). Global tRF expression pattern, just like microRNAs, can distinguish tissue types among placenta/decidua, fetal brain and fetal liver. In particular, 5' tRNA halves from tRNA^Gly, tRNA^Glu, tRNA^Val and tRNA^Lys are abundantly expressed in the normal mouse placenta/decidua. Moreover, tRF and microRNA levels in the maternal-fetal interface change dynamically over the course of embryonic development. To see if stress alters non-coding RNA expression at the maternal-fetal interface, we treated pregnant mice with a viral infection mimetic, which has been shown to promote autism-related phenotypes in the offspring. Acute changes in the levels of specific tRFs and microRNAs were observed 3-6 h after MIA and are suppressed thereafter. A group of 5' tRNA halves is down-regulated by MIA, whereas a group of 18-nucleotide tRF-3a is up-regulated. In conclusion, tRFs show tissue-specificity, developmental changes and acute response to environmental stress, opening the possibility of them having a role in the fetal response to MIA.

Transcriptional analysis of deoxynivalenol-induced apoptosis of sow ovarian granulosa cell

Litter size is one of the most important economic traits in pig production. Recent studies identified that deoxynivalenol (DON), a widespread toxin in fodder, was associated with animal prolificacy. However, the underlying mechanisms have not yet been completely elucidated. Here, we used porcine ovary granulosa cells (pGCs) as a vector to establish DON concentration-time models and performed cell morphology and transcriptome analysis to identify and analyse the effects of DON on reproductive performance in swine. The results showed that DON can induce morphological changes and apoptosis of pGCs, while inhibiting cell proliferation. Moreover, these effects of DON on pGCs were dose-dependent. After treatment of pGCs with different concentrations of DON, the percentage of cells in S phase and G2/M phase increased. RNA-seq analyses revealed 5,937 differentially expressed genes, of which 1995 were down-regulated and 3,942 were up-regulated after DON treatment. KEGG enrichment analysis indicated important metabolic pathways such as IL-17 signalling pathway, eukaryotic ribosome synthesis pathway, RNA transport pathway and RNA degradation. Based on our results, we speculate that the effects of DON are related to the DNA damage process. Our study provides novel insights and a foundation to further understand the effect of DON on swine prolificacy.

The role of non-coding RNAs in neuroprotection and angiogenesis following ischemic stroke

Stroke is the leading cause of death and physical disability worldwide. Non-coding RNAs (ncRNAs) are endogenous molecules that play key roles in the pathophysiology and retrieval processes following ischemic stroke. The potential of ncRNAs, especially microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) in neuroprotection and angiogenesis highlights their potential as targets for therapeutic intervention. In this review, we document the miRNAs and lncRNAs that have been reported to exert regulatory actions in neuroprotective and angiogenic processes through different mechanisms involving their interaction with target coding genes. We believe that exploration of the expression profiles and the possible functions of ncRNAs during the recovery processes will help comprehension of the molecular mechanisms responsible for neuroprotection and angiogenesis, and may also contribute to find biomarkers and targets for future stroke intervention.

Secukinumab attenuates reactive astrogliosis via IL-17RA/(C/EBPβ)/SIRT1 pathway in a rat model of germinal matrix hemorrhage

Aims

Reactive astrogliosis plays a critical role in neurological deficits after germinal matrix hemorrhage (GMH). It has been reported that interleukin‐17A and IL‐17A receptor IL‐17RA/(C/EBPβ)/SIRT1 signaling pathway enhances reactive astrogliosis after brain injuries. We evaluated the effects of secukinumab on reactive astrogliosis in a rat pup model of GMH.

Methods

A total of 146 Sprague Dawley P7 rat pups were used. GMH was induced by intraparenchymal injection of collagenase. Secukinumab was administered intranasally 1 hour post‐GMH. C/EBPβ CRISPR or SIRT1 antagonist EX527 was administrated intracerebroventricularly (icv) 48 hours and 1 hour before GMH induction, respectively. Neurobehavior, Western blot, histology, and immunohistochemistry were used to assess treatment regiments in the short term and long term.

Results

The endogenous IL‐17A, IL‐17RA, C/EBPβ, and GFAP and proliferation marker CyclinD1 were increased, while SIRT1 expression was decreased after GMH. Secukinumab treatment improved neurological deficits, reduced ventriculomegaly, and increased cortical thickness. Additionally, treatment increased SIRT1 expression and lowered proliferation proteins PCNA and CyclinD1 as well as GFAP expression. C/EBPβ CRISPR activation plasmid and EX527 reversed the antireactive astrogliosis effects of secukinumab.

Conclusion

Secukinumab attenuated reactive astrogliosis and reduced neurological deficits after GMH, partly by regulating IL‐17RA/(C/EBPβ)/SIRT1 pathways. Secukinumab may provide a promising therapeutic strategy for GMH patients.

microRNA-340-5p inhibits hypoxia/reoxygenation-induced apoptosis and oxidative stress in cardiomyocytes by regulating the Act1/NF-κB pathway

MicroRNAs (miRNAs) have been reported to play critical roles in the occurrence, progression, and treatment of many cardiovascular diseases. However, the molecular mechanism by which miRNA regulates target gene expression in ischemia-reperfusion (I/R) injury in acute myocardial infarction (AMI) is not entirely clear. MiR-340-5p was reported to be downregulated in acute ischemic stroke. However, it still remains unknown whether miR-340-5p is mediated in the pathogenesis process of I/R injury after AMI. In the present study, male C57BL/6 J mice and H9C2 cardiomyocytes were used as experimental models. Real-time polymerase chain reaction analysis, Western blot analysis, and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling immunofluorescence staining assay were conducted to examine related indicators in the study. We confirmed that the expression of miR-340-5p is downregulated after I/R in AMI mice and hypoxia/reperfusion (H/R)-induced cardiomyocytes. miR-340-5p could inhibit apoptosis and oxidative stress in H/R-induced H9C2 cells via downregulating activator 1 (Act1). The inhibiting action of miR-340-5p on H/R-induced apoptosis and oxidative stress in cardiomyocytes was partially reversed after Act1 overexpression. Moreover, the results showed that the NF-κB pathway may be mediated in the role of miR-340-5p on H/R-induced cardiomyocyte apoptosis and oxidative stress. We demonstrated that upregulation of miR-340-5p suppresses apoptosis and oxidative stress induced by H/R in H9C2 cells by inhibiting Act1. Therapeutic strategies that target miR-340-5p, Act1, and the NF-κB pathway could be beneficial for the treatment of I/R injury after AMI.

Nucleic Acid Therapies for Ischemic Stroke

Stroke remains a leading cause of disability and death worldwide despite significant scientific and therapeutic advances. Therefore, there is a critical need to improve stroke prevention and treatment. In this review, we describe several examples that leverage nucleic acid therapeutics to improve stroke care through prevention, acute treatment, and recovery. Aptamer systems are under development to increase the safety and efficacy of antithrombotic and thrombolytic treatment, which represent the mainstay of medical stroke therapy. Antisense oligonucleotide therapy has shown some promise in treating stroke causes that are genetically determined and resistant to classic prevention approaches such as elevated lipoprotein (a) and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Targeting microRNAs may be attractive because they regulate factors involved in neuronal cell death and reperfusion-associated injury, as well as neurorestorative pathways. Lastly, microRNAs may aid reliable etiologic classification of stroke subtypes, which is important for effective secondary stroke prevention.

Non-Coding RNA in Acute Ischemic Stroke: Mechanisms, Biomarkers and Therapeutic Targets

Non-coding RNAs (ncRNAs) are a class of functional RNAs that regulate gene expression in a post-transcriptional manner. NcRNAs include microRNAs, long non-coding RNAs and circular RNAs. They are highly expressed in the brain and are involved in the regulation of physiological and pathophysiological processes, including cerebral ischemic injury, neurodegeneration, neural development, and plasticity. Stroke is one of the leading causes of death and physical disability worldwide. Acute ischemic stroke (AIS) occurs when brain blood flow stops, and that stoppage results in reduced oxygen and glucose supply to cells in the brain. In this article, we review the latest progress on ncRNAs in relation to their implications in AIS, as well as their potential as diagnostic and prognostic biomarkers. We also review ncRNAs acting as possible therapeutic targets in future precision medicine. Finally, we conclude with a brief discussion of current challenges and future directions for ncRNAs studies in AIS, which may facilitate the translation of ncRNAs research into clinical practice to improve clinical outcome of AIS.