Inhibition of miR-19a-3p decreases cerebral ischemia/reperfusion injury by targeting IGFBP3 in vivo and in vitro

The ability of microRNAs to regulate the immune response in ischemia/reperfusion inflammatory pathways

MicroRNAs play a crucial role in regulating the immune responses induced by ischemia/reperfusion injury. Through their ability to modulate gene expression, microRNAs adjust immune responses by targeting specific genes and signaling pathways. This review focuses on the impact of microRNAs on the inflammatory pathways triggered during ischemia/reperfusion injury and highlights their ability to modulate inflammation, playing a critical role in the pathophysiology of ischemia/reperfusion injury. Dysregulated expression of microRNAs contributes to the pathogenesis of ischemia/reperfusion injury, therefore targeting specific microRNAs offers an opportunity to restore immune homeostasis and improve patient outcomes. Understanding the complex network of immunoregulatory microRNAs could provide novel therapeutic interventions aimed at attenuating excessive inflammation and preserving tissue integrity.

Unveiling the regulatory role of miRNAs in stroke pathophysiology and diagnosis

Stroke, a major global cause of mortality, leads to a range of problems for those who survive. Besides its brutal events, stroke also tends to have a characteristic of recurrence, making it a complex disease involving intricate regulatory networks. One of the major cellular regulators is the non-coding RNAs (ncRNA), specifically microRNAs (miRNAs), thus the possible functions of miRNAs in the pathogenesis of stroke are discussed as well as the possibility of using miRNA-based therapeutic approaches. Firstly, the molecular mechanisms by which miRNAs regulate vital physiological processes, including synaptic plasticity, oxidative stress, apoptosis, and the integrity of the blood-brain barrier (BBB) are reviewed. The miRNA indirectly impacts stroke outcomes by regulating BBB function and angiogenesis through the targeting of transcription factors and angiogenic factors. In addition, the tendency for some miRNAs to be upregulated in response to hypoxia, which is a prevalent phenomenon in stroke and various neurological disorders, highlights the possibility that it controls hypoxia-inducible factor (HIF) signaling and angiogenesis, thereby influencing the integrity of the BBB as examples of the discussed mechanisms. Furthermore, this review explores the potential therapeutic targets that miRNAs may offer for stroke recovery and highlights their promising capacity to alleviate post-stroke complications. This review provides researchers and clinicians with valuable resources since it attempts to decipher the complex network of miRNA-mediated mechanisms in stroke. Additionally, the review addresses the interplay between miRNAs and stroke risk factors as well as clinical applications of miRNAs as diagnostic and prognostic markers.

Expansion of plasma MicroRNAs over the first month following human stroke

Few have characterized miRNA expression during the transition from injury to neural repair and secondary neurodegeneration following stroke in humans. We compared expression of 754 miRNAs from plasma samples collected 5, 15, and 30 days post-ischemic stroke from a discovery cohort (n = 55) and 15-days post-ischemic stroke from a validation cohort (n = 48) to healthy control samples (n = 55 and 48 respectively) matched for age, sex, race and cardiovascular comorbidities using qRT-PCR. Eight miRNAs remained significantly altered across all time points in both cohorts including many described in acute stroke. The number of significantly dysregulated miRNAs more than doubled from post-stroke day 5 (19 miRNAs) to days 15 (50 miRNAs) and 30 (57 miRNAs). Twelve brain-enriched miRNAs were significantly altered at one or more time points (decreased expression, stroke versus controls: miR-107; increased expression: miR-99-5p, miR-127-3p, miR-128-3p, miR-181a-3p, miR-181a-5p, miR-382-5p, miR-433-3p, miR-491-5p, miR-495-3p, miR-874-3p, and miR-941). Many brain-enriched miRNAs were associated with apoptosis over the first month post-stroke whereas other miRNAs suggested a transition to synapse regulation and neuronal protection by day 30. These findings suggest that a program of decreased cellular proliferation may last at least 30 days post-stroke, and points to specific miRNAs that could contribute to neural repair in humans.

miR-188-5p silencing improves cerebral ischemia/reperfusion injury by targeting Lin28a

This report aimed to explore whether miR-188-5p regulated the pathological regulatory network of cerebral ischemia/reperfusion (I/R) injury. We simulated the cerebral I/R injury model with MACO/R and OGD/R treatments. Neuronal viability and apoptosis were assessed. The contents of miR-188-5p and Lin 28a were evaluated. The abundances of apoptosis-related proteins (Bax, Bcl-2, and cleaved caspase-3) and pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) were measured. The interaction of miR-188-5p and Lin28a was confirmed. Lin28a silencing was supplemented to determine the delicate regulation of miR-188-5p. We revealed that miR-188-5p was upregulated and Lin28a was downregulated in I/R rats and OGD/R-induced cells. miR-188-5p silencing remarkably reduced the cerebral infarction volume, neurobehavioral score, brain edema, and Evans blue leakage. miR-188-5p silencing enhanced neuronal viability and alleviated apoptosis. The abundance of Bax and cleaved caspase-3 was reduced by miR-188-5p silencing, while Bcl-2 was augmented. miR-188-5p silencing impeded the contents of TNF-α, IL-1β, and IL-6. miR-188-5p interacted with Lin28a and negatively regulated its expression. Interestingly, extra Lin28a silencing reversed apoptosis and the content of inflammatory cytokines. Our studies confirmed that miR-188-5p silencing alleviated neuronal apoptosis and inflammation by mediating the expression of Lin28a. The crosstalk of miR-188-5p and Lin28a offered a different direction for ischemic stroke therapy.

Neuronal Responses to Ischemia: Scoping Review of Insights from Human-Derived In Vitro Models

Translation of neuroprotective treatment effects from experimental animal models to patients with cerebral ischemia has been challenging. Since pathophysiological processes may vary across species, an experimental model to clarify human-specific neuronal pathomechanisms may help. We conducted a scoping review of the literature on human neuronal in vitro models that have been used to study neuronal responses to ischemia or hypoxia, the parts of the pathophysiological cascade that have been investigated in those models, and evidence on effects of interventions. We included 147 studies on four different human neuronal models. The majority of the studies (132/147) was conducted in SH-SY5Y cells, which is a cancerous cell line derived from a single neuroblastoma patient. Of these, 119/132 used undifferentiated SH-SY5Y cells, that lack many neuronal characteristics. Two studies used healthy human induced pluripotent stem cell derived neuronal networks. Most studies used microscopic measures and established hypoxia induced cell death, oxidative stress, or inflammation. Only one study investigated the effect of hypoxia on neuronal network functionality using micro-electrode arrays. Treatment targets included oxidative stress, inflammation, cell death, and neuronal network stimulation. We discuss (dis)advantages of the various model systems and propose future perspectives for research into human neuronal responses to ischemia or hypoxia.

The Role of microRNAs in Epigenetic Regulation of Signaling Pathways in Neurological Pathologies

In recent times, there has been a significant increase in researchers' interest in the functions of microRNAs and the role of these molecules in the pathogenesis of many multifactorial diseases. This is related to the diagnostic and prognostic potential of microRNA expression levels as well as the prospects of using it in personalized targeted therapy. This review of the literature analyzes existing scientific data on the involvement of microRNAs in the molecular and cellular mechanisms underlying the development of pathologies such as Alzheimer's disease, cerebral ischemia and reperfusion injury, and dysfunction of the blood-brain barrier.

MicroRNA-204-5p Ameliorates Neurological Injury via the EphA4/PI3K/AKT Signaling Pathway in Ischemic Stroke

Ischemic stroke has extremely high mortality and disability rates worldwide. miR-204-5p has been reported to be associated with neurological diseases. However, the relationship linking miR-204-5p to ischemic stroke and its molecular mechanism remain unclear. Herein, we found that expression of miR-204-5p was significantly decreased while EphA4 increased in vivo and vitro, which reached the peak at 24 h after cerebral ischemia/reperfusion. Then, we altered miR-204-5p expression in rats by cerebroventricular injection. Our study showed that miR-204-5p overexpression obviously reduced the brain infarction area and neurological score. We successfully cultured neurons to investigate the downstream mechanism. Upregulation of miR-204-5p increased cell viability and suppressed the release of LDH. Moreover, the proportion of apoptotic cells tested by TUNEL and flow cytometry and protein expression of Cleaved Caspase3 and Bax were inhibited. The relative expression of IL-6, TNF-α, and IL-1β was repressed. In contrary, knockdown of miR-204-5p showed the opposite results. Bioinformatics and a dual luciferase assay illustrated that EphA4 was a target gene. Further research studies demonstrated that the neuroprotective effects of miR-204-5p could be partially mitigated by upregulating EphA4. Next, we proved that the miR-204-5p/EphA4 axis furtherly activated the PI3K/AKT pathway. We thoroughly illustrated the role of neuroinflammation and apoptosis. However, whether there are other mechanisms associated with the EphA4/PI3K/AKT pathway needs further investigation. Altogether, the miR-204-5p axis ameliorates neurological injury via the EphA4/PI3K/AKT pathway, which is expected to serve as an effective treatment for ischemic stroke.

The Role of LincRNA-EPS/Sirt1/Autophagy Pathway in the Neuroprotection Process by Hydrogen against OGD/R-Induced Hippocampal HT22 Cells Injury

Cerebral ischemia/reperfusion (CI/R) injury causes high disability and mortality. Hydrogen (H2) enhances tolerance to an announced ischemic event; however, the therapeutic targets for the effective treatment of CI/R injury remain uncertain. Long non-coding RNA lincRNA-erythroid prosurvival (EPS) (lincRNA-EPS) regulate various biological processes, but their involvement in the effects of H2 and their associated underlying mechanisms still needs clarification. Herein, we examine the function of the lincRNA-EPS/Sirt1/autophagy pathway in the neuroprotection of H2 against CI/R injury. HT22 cells and an oxygen-glucose deprivation/reoxygenation (OGD/R) model were used to mimic CI/R injury in vitro. H2, 3-MA (an autophagy inhibitor), and RAPA (an autophagy agonist) were then administered, respectively. Autophagy, neuro-proinflammation, and apoptosis were evaluated by Western blot, enzyme-linked immunosorbent assay, immunofluorescence staining, real-time PCR, and flow cytometry. The results demonstrated that H2 attenuated HT22 cell injury, which would be confirmed by the improved cell survival rate and decreased levels of lactate dehydrogenase. Furthermore, H2 remarkably improved cell injury after OGD/R insult via decreasing pro-inflammatory factors, as well as suppressing apoptosis. Intriguingly, the protection of H2 against neuronal OGD/R injury was abolished by rapamycin. Importantly, the ability of H2 to promote lincRNA-EPS and Sirt1 expression and inhibit autophagy were abrogated by the siRNA-lincRNA-EPS. Taken together, the findings proved that neuronal cell injury caused by OGD/R is efficiently prevented by H2 via modulating lincRNA-EPS/Sirt1/autophagy-dependent pathway. It was hinted that lincRNA-EPS might be a potential target for the H2 treatment of CI/R injury.

Activation of the Epac/Rap1 signaling pathway alleviates blood-brain barrier disruption and brain damage following cerebral ischemia/reperfusion injury

Blood brain barrier (BBB) destruction plays a key role in ischemia stroke, including promoting BBB leakage and brain edema, and leads to unfavorable patient prognosis. Epac/Rap1 signaling pathway is important in mediating endothelial cell barrier function. This study will investigate the regulatory role of Epac/Rap1 signaling pathway in BBB disruption after cerebral ischemia/reperfusion (CI/R) injury. CI/R model was induced by 90 min of transient middle cerebral artery occlusion (MCAO) in male C57BL/6J mice. Injection of Epac/Rap1 signaling pathway agonist was performed half an hour before the MCAO operation. The results showed that CI/R injured the tight connection of BBB and evoked the suppression of the Epac/Rap1 signaling pathway. Based on Epac activation with a cAMP analogue, 8-CPT could improve BBB disfunction by increasing the expression of tight junction protein and reducing the formation of stress fibers. In addition, 8-CPT could ameliorate neurobehavioral disorders, cerebral edema, and cerebral infarction volume in MCAO mice. Moreover, inhibition of Epac pathway with Rap1 inhibitor GGTI298 and Rac1 inhibitor NSC23766 could aggravate the damage of BBB and cerebral injury accordingly. Our results indicate that, the activation of Epac/Rap1 signaling pathway has neuroprotective effects on CI/R damaged brain, through the recovery of BBB.

The diverse roles of macrophages in metabolic inflammation and its resolution

Macrophages are one of the most functionally diverse immune cells, indispensable to maintain tissue integrity and metabolic health. Macrophages perform a myriad of functions ranging from promoting inflammation, through inflammation resolution to restoring and maintaining tissue homeostasis. Metabolic diseases encompass a growing list of diseases which develop from a mix of genetics and environmental cues leading to metabolic dysregulation and subsequent inflammation. In this review, we summarize the contributions of macrophages to four metabolic conditions-insulin resistance and adipose tissue inflammation, atherosclerosis, non-alcoholic fatty liver disease and neurodegeneration. The role of macrophages is complex, yet they hold great promise as potential therapies to address these growing health concerns.

Up-regulating microRNA-214-3p relieves hypoxic-ischemic brain damage through inhibiting TXNIP expression

A list of microRNAs (miRs) has been referred to involve in the development of hypoxic-ischemic brain damage (HIBD). Based on that, we probed the concrete role of miR-214-3p regulating thioredoxin-interacting protein (TXNIP) in the illness. A neonatal HIBD mouse model was established using the Rice-Vannucci method, followed by measurements of miR-214-3p and TXNIP levels in brain tissues. After modeling, mice were given brain injection of the compounds that could alter miR-214-3p and TXNIP expression. Afterward, neurological function, neuronal inflammation, neuronal apoptosis, neuron morphology, and the number of Nissl body were assessed in HIBD mice. The binding of miR-214-3p to TXNIP was analyzed. Lower miR-214-3p and higher TXNIP were analyzed in brain tissues of mice with HIBD. Up-regulating miR-214-3p or depleting TXNIP improved neurological function, reduced neuronal inflammation and neuronal apoptosis, attenuated morphological damage of neurons, and increased the number of Nissl bodies in mice with HIBD. TXNIP was targeted by miR-214-3p and overexpressing TXNIP reversed the therapeutic effect of miR-214-3p on HIBD mice. It is noted that promotion of miR-214-3p relieves HIBD in mice through inhibiting TXNIP expression.

Silencing of the circ-Arhgap5 RNA protects neuronal PC12 cells against injury and depends on the miR-29a-3p/Rock1 axis

Circular RNAs (circRNAs) are abundantly expressed in human central nervous system. Here, we explored the role of circ_Arhgap5 in cerebral ischemia/reperfusion (I/R)-induced nerve injury in PC12 cells and its associated mechanism. Cell proliferation ability was assessed by 5-Ethynyl-2'-deoxyuridine (Edu) assay and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry (FCM) was applied to assess cell apoptotic rate. Cell death was analyzed by lactate dehydrogenase (LDH) assay. Oxygen-glucose deprivation and reoxygenation (OGD/R) up-regulates the expression of circRNA Rho GTPase activating protein 5 (circ_Arhgap5; mmu_circ_0000377) in PC12 cells. OGD/R exposure inhibited the proliferation and induced the apoptosis of PC12 cells, and the silence of circ_Arhgap5 attenuated OGD/R-induced injury in PC12 cells. miR-29a-3p was identified as a target of circ_Arhgap5 in PC12 cells. Circ_Arhgap5 knockdown-mediated protective effects in OGD/R-induced PC12 cells were reversed by the interference of miR-29a-3p. miR-29a-3p interacted with the 3' untranslated region (3'UTR) of Rho-associated coiled-coil-containing protein kinase 1 (Rock1), and circ_Arhgap5 can positively regulate Rock1 expression by sponging miR-29a-3p in PC12 cells. miR-29a-3p overexpression protected PC12 cells against OGD/R-induced damage by down-regulating Rock1. In conclusion, circ_Arhgap5 silencing protected PC12 cells from OGD/R-induced injury through mediating miR-29a-3p/Rock1 axis.

Inhibition of microRNA-19a-3p alleviates the neuropathic pain (NP) in rats after chronic constriction injury (CCI) via targeting KLF7

BACKGROUND/PURPOSE

Neuropathic pain(NP) is derived from the dysfunctions of nerve system. The current research is to explore the impact and mechanism of miR-19a-3p in neuropathic pain in rats.

METHODS

The NP was induced through the chronic constriction injury (CCI) surgery in rats. The pro-inflammatory factors (IL-1β, IL-6, TNF-α) in spinal cord tissues from rats were measured using Elisa kits. Moreover, the different levels of thermal hyperalgesia and mechanical allodynia in rats were examined through paw withdrawal latency (PWL) and paw withdrawal threshold (PWT). To investigate into the role of miR-19a-3p and KLF7 in NP of rats, the knockdown of miR-19a-3p alone or along with KLF7 downregulation in rats were achieved through lentivirus injection. The miR-19a-3p and KLF7 expression in spinal cord of rats on Day 3,7,14 after CCI were detected using RT-qPCR. The protein expression of KLF7 were measured by Western blot. Bioinformatics and luciferase assays were used for the prediction and verification of bindings between KLF7 and miR-19a-3p.

RESULTS

CCI surgery caused neuropathic pain in rats with the levels of inflammatory cytokines increased and PWL and PWT decreased. Moreover, miR-19a-3p expression was increased while the protein and mRNA levels were decreased in spinal cord tissues in rats after CCI surgery. In rat microglial cells, miR-19a-3p downregulation could promote the KLF7 in both mRNA and protein expression. In spinal cord tissues of rats, the inhibition of miR-19a-3p enhanced the KLF7 expression. Furthermore, miR-19a-3p downregulation suppressed the IL-1β, IL-6 and TNF-α concentrations, and could decrease the NP but inhibition of KLF7 could partially reverse this in CCI rats.

CONCLUSION

miR-19a-3p inhibition may alleviate NP via KLF7 in CCI rats.

Chemokine receptor 7 mediates miRNA-182 to regulate cerebral ischemia/reperfusion injury in rats

AIMS

Chemokine receptor 7 (CXCR7) exerts protective effects on the brain. MicroRNAs (miRNAs) are involved in cerebral ischemia/reperfusion (I/R) injury, but their involvement in CXCR7-mediated brain protection is unknown. In this study, we investigated the role of miRNAs in CXCR7-mediated brain protection.

METHODS

CXCR7 levels in peripheral blood samples from patients with acute ischemic stroke (AIS) and ischemic penumbra area brain tissues from middle cerebral artery occlusion (MCAO) rats after recanalization were measured. An miRNA microarray analysis was performed to examine the expression of miRNAs caused by CXCR7 knockdown in ischemic penumbra area brain tissue in middle cerebral artery occlusion-reperfusion rats and to predict corresponding downstream target genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed the most enriched pathways. A dual-luciferase reporter assay confirmed the direct regulation of miR-182 on the target gene TCF7L2. The correlation between TCF7L2 and CXCR7/miR-182 was verified using rescue assays.

RESULTS

CXCR7 expression was upregulated in MCAO rats and mechanical thrombectomy patients with AIS compared to that in controls. The motor and sensory functions of MCAO rats with CXCR7 knockdown further decreased, and the infarct volume and cerebral edema increased. miRNA microarray data showed that seven miRNAs were differentially expressed after shRNA-CXCR7 treatment. The dual-luciferase reporter assay confirmed that miR-182 directly targeted the TCF7L2 gene. Rescue assays confirmed that TCF7L2 is downstream of CXCR7/miR-182. KEGG pathway analysis showed that the Hippo pathway may be a key pathway in CXCR7 upregulation and plays a role in protecting the brain after interventional surgery. Animal experiments have shown that CXCR7-mediated cerebral I/R injury promotes the phosphorylation of key molecules YAP and TAZ in the Hippo pathway.

CONCLUSION

CXCR7 protects against cerebral I/R injury, possibly via the miR-182/TCF7L2/Hippo pathway. These results indicate that CXCR7 affects cerebral ischemia-reperfusion injury through miRNA regulation and downstream pathways.

miRNA Involvement in Cerebral Ischemia-Reperfusion Injury

Cerebral ischemia reperfusion injury is a debilitating medical condition, currently with only a limited amount of therapies aimed at protecting the cerebral parenchyma. Micro RNAs (miRNAs) are small, non-coding RNA molecules that via the RNA-induced silencing complex either degrade or prevent target messenger RNAs from being translated and thus, can modulate the synthesis of target proteins. In the neurological field, miRNAs have been evaluated as potential regulators in brain development processes and pathological events. Following ischemic hypoxic stress, the cellular and molecular events initiated dysregulate different miRNAs, responsible for long-terming progression and extension of neuronal damage. Because of their ability to regulate the synthesis of target proteins, miRNAs emerge as a possible therapeutic strategy in limiting the neuronal damage following a cerebral ischemic event. This review aims to summarize the recent literature evidence of the miRNAs involved in signaling and modulating cerebral ischemia-reperfusion injuries, thus pointing their potential in limiting neuronal damage and repair mechanisms. An in-depth overview of the molecular pathways involved in ischemia reperfusion injury and the involvement of specific miRNAs, could provide future perspectives in the development of neuroprotective agents targeting these specific miRNAs.

Noncoding RNA actions through IGFs and IGF binding proteins in cancer

The insulin-like growth factors (IGFs) and their regulatory proteins—IGF receptors and binding proteins—are strongly implicated in cancer progression and modulate cell survival and proliferation, migration, angiogenesis and metastasis. By regulating the bioavailability of the type-1 IGF receptor (IGF1R) ligands, IGF-1 and IGF-2, the IGF binding proteins (IGFBP-1 to -6) play essential roles in cancer progression. IGFBPs also influence cell communications through pathways that are independent of IGF1R activation. Noncoding RNAs (ncRNAs), which encompass a variety of RNA types including microRNAs (miRNAs) and long-noncoding RNAs (lncRNAs), have roles in multiple oncogenic pathways, but their many points of intersection with IGF axis functions remain to be fully explored. This review examines the functional interactions of miRNAs and lncRNAs with IGFs and their binding proteins in cancer, and reveals how the IGF axis may mediate ncRNA actions that promote or suppress cancer. A better understanding of the links between ncRNA and IGF pathways may suggest new avenues for prognosis and therapeutic intervention in cancer. Further, by exploring examples of intersecting ncRNA-IGF pathways in non-cancer conditions, it is proposed that new opportunities for future discovery in cancer control may be generated.

Hypoxic/Ischemic Inflammation, MicroRNAs and δ-Opioid Receptors: Hypoxia/Ischemia-Sensitive Versus-Insensitive Organs

Hypoxia and ischemia cause inflammatory injury and critically participate in the pathogenesis of various diseases in various organs. However, the protective strategies against hypoxic and ischemic insults are very limited in clinical settings up to date. It is of utmost importance to improve our understanding of hypoxic/ischemic (H/I) inflammation and find novel therapies for better prevention/treatment of H/I injury. Recent studies provide strong evidence that the expression of microRNAs (miRNAs), which regulate gene expression and affect H/I inflammation through post-transcriptional mechanisms, are differentially altered in response to H/I stress, while δ-opioid receptors (DOR) play a protective role against H/I insults in different organs, including both H/I-sensitive organs (e.g., brain, kidney, and heart) and H/I-insensitive organs (e.g., liver and muscle). Indeed, many studies have demonstrated the crucial role of the DOR-mediated cyto-protection against H/I injury by several molecular pathways, including NLRP3 inflammasome modulated by miRNAs. In this review, we summarize our recent studies along with those of others worldwide, and compare the effects of DOR on H/I expression of miRNAs in H/I-sensitive and -insensitive organs. The alternation in miRNA expression profiles upon DOR activation and the potential impact on inflammatory injury in different organs under normoxic and hypoxic conditions are discussed at molecular and cellular levels. More in-depth investigations into this field may provide novel clues for new protective strategies against H/I inflammation in different types of organs.

Diagnostic Performance of Circulating miRNAs and Extracellular Vesicles in Acute Ischemic Stroke

Background: Increased inflammation activates blood coagulation system, higher platelet activation plays a key role in the pathophysiology of ischemic stroke (IS). During platelet activation and aggregation process, platelets may cause increased release of several proinflammatory, and prothrombotic mediators, including microRNAs (miRNAs) and extracellular vesicles (EVs). In the current study we aimed to assess circulating miRNAs profile related to platelet function and inflammation and circulating EVs from platelets, leukocytes, and endothelial cells to analyse their diagnostic and predictive utility in patients with acute IS. Methods: The study population consisted of 28 patients with the diagnosis of the acute IS. The control group consisted of 35 age- and gender-matched patients on acetylsalicylic acid (ASA) therapy without history of stroke and/or TIA with established stable coronary artery disease (CAD) and concomitant cardiovascular risk factors. Venous blood samples were collected from the control group and patients with IS on ASA therapy (a) 24 h after onset of acute IS, (b) 7-days following index hospitalization. Flow cytometry was used to determine the concentration of circulating EVs subtypes (from platelets, leukocytes, and endothelial cells) in platelet-depleted plasma and qRT-PCR was used to determine several circulating plasma miRNAs (miR-19a-3p, miR-186-5p and let-7f). Results: Patients with high platelet reactivity (HPR, based on arachidonic acid-induced platelet aggregometry) had significantly elevated platelet-EVs (CD62+) and leukocyte-EVs (CD45+) concentration compared to patients with normal platelet reactivity at the day of 1 acute-stroke (p = 0.012, p = 0.002, respectively). Diagnostic values of baseline miRNAs and EVs were evaluated with receiver operating characteristic (ROC) curve analysis. The area under the ROC curve for miR-19a-3p was 0.755 (95% CI, 0.63–0.88) p = 0.004, for let-7f, it was 0.874 (95% CI, 0.76–0.99) p = 0.0001; platelet-EVs was 0.776 (95% CI, 0.65–0.90) p = 0.001, whereas for leukocyte-EVs, it was 0.715 (95% CI, 0.57–0.87) p = 0.008. ROC curve showed that pooling the miR-19a-3p expressions, platelet-EVs, and leukocyte-EVs concentration yielded a higher AUC than the value of each individual biomarker as AUC was 0.893 (95% CI, 0.79–0.99). Patients with moderate stroke had significantly elevated miR-19a-3p expression levels compared to patients with minor stroke at the first day of IS. (AUC: 0.867, (95% CI, 0.74–0.10) p = 0.001). Conclusion: Combining different biomarkers of processes underlying IS pathophysiology might be beneficial for early diagnosis of ischemic events. Thus, we believe that in the future circulating biomarkers might be used in the prehospital phase of IS. In particular, circulating plasma EVs and non-coding RNAs including miRNAs are interesting candidates as bearers of circulating biomarkers due to their high stability in the blood and making them highly relevant biomarkers for IS diagnostics.

FTX Attenuates Cerebral Ischemia-Reperfusion Injury by Inhibiting Apoptosis and Oxidative Stress via miR-186-5p/MDM4 Pathway

LncRNA five prime to Xist (FTX) has been identified to exert a protective effect in multiple diseases. However, whether and how FTX attenuates cerebral ischemia-reperfusion injury (CI/RI) is still unclear. To simulate CI/RI, an in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) HT22 cell model and an in vivo middle cerebral artery occlusion/reperfusion (MCAO/R) Sprague-Dawley rat model were respectively constructed. In CI/RI plasma samples, OGD/R-challenged HT22 cells, and brain tissues from MCAO/R rats, FTX and mouse double minute 4 (MDM4) expressions were substantially decreased while miR-186-5p abundance was evidently increased. It was also revealed that FTX obviously improved neuronal damage induced by OGD/R through increasing proliferation, reducing apoptosis, and alleviating oxidative stress in OGD/R-challenged HT22 cells. Additionally, FTX positively regulated MDM4 level in OGD/R-treated HT22 cells as a sponge of miR-186-5p. Moreover, miR-186-5p upregulation or MDM4 suppression restored the inhibitory effects of FTX upregulation on OGD/R-triggered neuronal damage in HT22 cells. Therefore, these results suggest that FTX might ameliorate CI/RI by regulating the miR-186-5p/MDM4 pathway, providing a new target for stroke impairment treatment.

Overexpression of microRNA-381-3p ameliorates hypoxia/ischemia-induced neuronal damage and microglial inflammation via regulating the C-C chemokine receptor type 2 /nuclear transcription factor-kappa B axis

microRNAs, as small endogenous RNAs, influence umpteen sophisticated cellular biological functions regarding neurodegenerative and cerebrovascular diseases. Here, we interrogated miR-381-3p’s influence on BV2 activation and neurotoxicity in ischemic and hypoxic environment. Oxygen-glucose deprivation (OGD) was adopted to induce microglial activation and HT-22 neuron damage. Quantitative polymerase chain reaction (qRT-PCR) was taken to check miR-381-3p expression in OGD-elicited BV2 cells and HT-22 neurons. It transpired that miR-381-3p expression was lowered in BV2 cells and HT-22 cells elicited by OGD. miR-381-3p up-regulation remarkably hampered inflammatory mediator expression in BV2 cells induced by OGD and weakened HT22 neuron apoptosis. In vivo, miR-381-3p expression was abated in HI rats’ ischemic lesions, and miR-381-3p up-regulation could ameliorate inflammation and neuron apoptosis in their brain. C-C chemokine receptor type 2 (CCR2) was identified as the downstream target of miR-381-3p, and miR-381-3p suppressed the CCR2/NF-κB pathway to mitigate microglial activation and neurotoxicity. Therefore, we believed that miR-381-3p overexpression exerts anti-inflammation and anti-apoptosis in ischemic brain injury by targeting CCR2

Comprehensive Analysis of the Effect of 20(R)-Ginsenoside Rg3 on Stroke Recovery in Rats via the Integrative miRNA-mRNA Regulatory Network

MicroRNAs (miRNAs) are a class of small, endogenous, noncoding RNAs. Recent research has proven that miRNAs play an essential role in the occurrence and development of ischemic stroke. Our previous studies confirmed that 20(R)-ginsenosideRg3 [20(R)-Rg3] exerts beneficial effects on cerebral ischemia-reperfusion injury (CIRI), but its molecular mechanism has not been elucidated. In this study, we used high-throughput sequencing to investigate the differentially expressed miRNA and mRNA expression profiles of 20(R)-Rg3 preconditioning to ameliorate CIRI injury in rats and to reveal its potential neuroprotective molecular mechanism. The results show that 20(R)-Rg3 alleviated neurobehavioral dysfunction in MCAO/R-treated rats. Among these mRNAs, 953 mRNAs were significantly upregulated and 2602 mRNAs were downregulated in the model group versus the sham group, whereas 437 mRNAs were significantly upregulated and 35 mRNAs were downregulated in the 20(R)-Rg3 group in contrast with those in the model group. Meanwhile, the expression profile of the miRNAs showed that a total of 283 differentially expressed miRNAs were identified, of which 142 miRNAs were significantly upregulated and 141 miRNAs were downregulated in the model group compared with the sham group, whereas 34 miRNAs were differentially expressed in the 20(R)-Rg3 treatment group compared with the model group, with 28 miRNAs being significantly upregulated and six miRNAs being significantly downregulated. Furthermore, 415 (391 upregulated and 24 downregulated) differentially expressed mRNAs and 22 (17 upregulated and 5 downregulated) differentially expressed miRNAs were identified to be related to 20(R)-Rg3's neuroprotective effect on stroke recovery. The Kyoto Encyclopedia of Genes and Genomes (KEGG) results showed that 20(R)-Rg3 could modulate multiple signaling pathways related to these differential miRNAs, such as the cGMP-PKG, cAMP and MAPK signaling pathways. This study provides new insights into the protective mechanism of 20(R)-Rg3 against CIRI, and the mechanism may be partly associated with the regulation of brain miRNA expression and its target signaling pathways.

Serum Exosomal mir-340-5p Promotes Angiogenesis in Brain Microvascular Endothelial Cells During Oxygen-Glucose Deprivation

Ischemic stroke (IS) is a cerebrovascular disease with high morbidity, recurrence, and mortality. The purpose of the present study was to investigate the role and mechanism of human serum exosomes on angiogenesis after IS. The middle cerebral artery occlusion (MCAO) in vivo model and oxygen-glucose deprivation (OGD) in vitro model were established. Human serum exosomes from healthy samples (NC-exo) and IS samples (IS-exo) were injected into MCAO mice. Neurobehavioral tests were performed to assess the extent of neurological deficits. The infarct volume was assessed by 2,3,5-triphenyl tetrazolium chloride (TTC) staining, and the levels of inflammatory cytokines were analyzed by enzyme-linked immunosorbent assay (ELISA). In addition, human serum exosomes were cocultured with brain microvascular endothelial cells (BMECs). Cell Counting Kit-8 (CCK-8), Transwell, and tubule formation assays were performed to investigate the proliferation, migration, invasion, length, and branching of BMECs. The miRNA expression profiles of NC-exo and IS-exo were analyzed by high-throughput sequencing and compared. Bioinformatics and luciferase reporter assays were performed to evaluate the relationship between miR-340-5p and CD147. Serum NC-exo and IS-exo had protective effects on IS injury and promoted BMEC angiogenesis. Interestingly, the protective effect of IS-exo was weaker than that of NC-exo. In addition, miR-340-5p was downregulated in IS-exo, and miR-340-5p accelerated angiogenesis of BMECs after OGD. Mechanistically, CD147 was confirmed as a direct target of miR-340-5p. Finally, miR-340-5p promoted angiogenesis by directly targeting CD147. Serum exosome-derived miR-340-5p promote angiogenesis in OGD-induced BMECs by targeting CD147.

RNA-seq analysis reveals potential molecular mechanisms of ZNF580/ZFP580 promoting neuronal survival and inhibiting apoptosis after Hypoxic-ischemic brain damage

Neonatal hypoxic-ischemic brain damage (HIBD) is one of the main causes of neonatal acute death and chronic nervous system impairment, but still lacks effective treatments. ZNF580/ZFP580, reported in our previous studies, may be a newly identified member of the Krüppel-like factor (KLF) family, and has anti-apoptotic effects during ischemic myocardial injury. In the present study, we showed that the expression levels of both ZFP580/ZNF580 mRNA and protein increased significantly in neonatal HIBD rats and oxygen-glucose deprivation (OGD) SH-SY5Y cell models. ZNF580 overexpression promoted neuron survival and suppressed neuron apoptosis after OGD in neuron-like SH-SY5Y cells, while interference with ZNF580 resulted in the opposite results. RNA-seq analysis identified 248 differentially-expressed genes (DEGs) between ZNF580 overexpression SH-SY5Y cells and interference-expressed SH-SY5Y cells. Gene Ontology functional enrichment analysis showed that these DEGs played significant roles in the growth, development, and regeneration of axons, DNA biosynthetic processes, DNA replication, and apoptosis. Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that these DEGs were found in some pathways, including ferroptosis, glutamatergic synapses, protein processing in the endoplasmic reticulum, estrogen signaling pathways, the TGF-beta signaling pathway, and the longevity regulating pathway. The qRT-PCR validation results were consistent with RNA-seq results, which showed that HSPA5, IGFBP3, NTN4, and KLF9 increased in ZNF580-overexpressed SH-SY5Y cells and decreased in interference-expressed SH-SY5Y cells, when compared with normal cells. Together, the results suggested that ZNF580 targeted these genes to inhibit neuronal apoptosis.

MiR-361-5p promotes oxygen-glucose deprivation/re-oxygenation induced neuronal injury by negatively regulating SQSTM1 in vitro

It has been reported that microRNAs (miRNAs) play essential roles in cerebral ischemia and reperfusion (I/R) injury. This study aimed to explore the role of miR-361-5p in oxygen-glucose deprivation/re-oxygenation-induced neuronal injury in vitro. Cerebral I/R injury cell model was established by using PC12 cells exposed to oxygen-glucose deprivation/re-oxygenation (OGD/R). The expression of miR-361-5p and SQSTM1 was evaluated by qRT-PCR or western blot. Neuronal apoptosis was detected by flow cytometry, and cell viability was assessed by CCK-8 assay. The effects of miR-361-5p on the release of LDH and the levels of MDA, SOD, and GSH-Px were investigated by respective detection kits. Dual-luciferase reporter assay and RIP assay were performed to determine the interaction between miR-361-5p and SQSTM1. Rescue experiments were performed to evaluate the function of miR-361-5p and SQSTM1. MiR-361-5p was significantly upregulated, and SQSTM1 was significantly downregulated in OGD/R-stimulated PC12 cells. MiR-361-5p could directly interact with SQSTM1 and negatively regulated it. Inhibition of miR-361-5p efficiently inhibited OGD/R-induced apoptosis and attenuated OGD/R-induced growth defect in PC12 cells. In addition, SQSTM1 overexpression partially attenuates the apoptosis and promoted the viability of OGD/R-treated PC12 cells, which were aggravated by miR-361-5p mimics. Our study demonstrated that miR-361-5p promotes OGD/R-induced neuronal injury via regulating SQSTM1 in PC12 cells.

LncRNA KCNQ1OT1 (potassium voltage-gated channel subfamily Q member 1 opposite strand/antisense transcript 1) aggravates acute kidney injury by activating p38/NF-κB pathway via miR-212-3p/MAPK1 (mitogen-activated protein kinase 1) axis in sepsis

Acute kidney injury (AKI), a common complication of sepsis, is characterized by a rapid loss of renal excretory function. A variety of etiologies and pathophysiological processes may contribute to AKI. Previously, mitogen-activated protein kinase 1 (MAPK1) was reported to regulate cellular processes in various sepsis-associated diseases. The current study aimed to further explore the biological function and regulatory mechanism of MAPK1 in sepsis-induced AKI. In our study, MAPK1 exhibited high expression in the serum of AKI patients. Functionally, knockdown of MAPK1 suppressed inflammatory response, cell apoptosis in response of lipopolysaccharide (LPS) induction in HK-2 cells. Moreover, MAPK1 deficiency alleviated renal inflammation, renal dysfunction, and renal injury in vivo. Mechanistically, MAPK1 could activate the downstream p38/NF-κB pathway. Moreover, long noncoding RNA potassium voltage-gated channel subfamily Q member 1 opposite strand/antisense transcript 1 (KCNQ1OT1) was identified to serve as a competing endogenous RNA for miR-212-3p to regulate MAPK1. Finally, rescue assays indicated that the inhibitory effect of KCNQ1OT1 knockdown on inflammatory response, cell apoptosis, and p38/NF-κB pathway was reversed by MAPK1 overexpression in HK-2 cells. In conclusion, KCNQ1OT1 aggravates acute kidney injury by activating p38/NF-κB pathway via miR-212-3p/MAPK1 axis in sepsis. Therefore, KCNQ1OT may serve as a potential biomarker for the prognosis and diagnosis of AKI patients.

Sevoflurane protects against cerebral ischemia/reperfusion injury via microrna-30c-5p modulating homeodomain-interacting protein kinase 1

Sevoflurane (SEV) has been reported to be an effective neuroprotective agent for cerebral ischemia/reperfusion injury (CIRI). However, the precise molecular mechanisms of Sev preconditioning in CIRI remain largely unknown. Therefore, CIRI model was established via middle cerebral artery occlusion method. SEV was applied before modeling. after successful modeling, lentivirus was injected into the lateral ventricle of the brain. Neurological impairment score was performed in each group, and histopathologic condition, infarct volume, apoptosis, inflammation, oxidative stress, microRNA (miR)-30 c-5p and homeodomain-interacting protein kinase 1 (HIPK1) were detected. Mouse hippocampal neuronal cell line HT22 cells were pretreated with SEV, and the in vitro model was stimulated via oxygen-glucose deprivation and reoxygenation. The corresponding plasmids were transfected, and the cell growth was detected, including inflammation and oxidative stress, etc. The targeting of miR-30 c-5p with HIPK1 was examined. The results clarified that reduced miR-30 c-5p and elevated HIPK1 were manifested in CIRI. SEV could improve CIRI and modulate the miR-30 c-5p-HIPK1 axis in vitro and in vivo, and miR-30 c-5p could target HIPK1. Depressed miR-30 c-5p could eliminate the protection of SEV in vitro and in vivo. Repression of HIPK1 reversed the effect of reduced miR-30 c-5p on CIRI. Therefore, it is concluded that SEV is available to depress CIRI via targeting HIPK1 through upregulated miR-30 c-5p.

Foxp3 attenuates cerebral ischemia/reperfusion injury through microRNA-150-5p-modified NCS1

OBJECTIVE

Cerebral ischemia/reperfusion injury (CI/RI) is a pathological process involving complicated molecular mechanisms. We investigated forkhead box P3 (Foxp3)-related mechanism in CI/RI with particular focus on microRNA (miR)-150-5p/nucleobase cation symporter-1 (NCS1) axis.

METHODS

A mouse model was constructed by middle cerebral artery occlusion (MCAO) method. Levels of Foxp3, miR-150-5p and NCS1 were assessed in brain tissues of MCAO mice. By determining the neurological behavior function, neurological deficits, brain tissue pathological characteristics, neuronal apoptosis, inflammatory factors, and oxidative stress-related factors, the functional role of Foxp3, miR-150-5p and NCS1 were evaluated in MCAO mice. The feedback loop was analyzed among Foxp3, miR-150-5p and NCS1.

RESULTS

The level of Foxp3 and NCS1 were reduced and that of miR-150-5p was augmented in MCAO mice. Foxp3 bound to miR-150-5p to target NCS1. Up-regulating Foxp3 or NCS1 or suppressing miR-150-5p improved neurological behavior function and neurological deficits, and reduced brain tissue pathological damage, neuronal apoptosis, inflammatory and oxidative stress reactions in MCAO mice. Silencing miR-150-5p or elevating NCS1 decreased Foxp3 silencing-mediated ischemic injury in MCAO mice.

CONCLUSION

Foxp3 is neuroprotective in CI/RI through binding to miR-150-5p to promote NCS1 expression.

ATP2B1-AS1 Promotes Cerebral Ischemia/Reperfusion Injury Through Regulating the miR-330-5p/TLR4-MyD88-NF-κB Signaling Pathway

We aim to explore the expression and function of long non-coding RNA (lncRNA) ATP2B1-AS1 in a cerebral ischemia/reperfusion (I/R) injury. In this study, we established a middle cerebral artery occlusion/reperfusion (MCAO/IR) rat model and an OGD/R PC12 cell model to evaluate the expression and role of ATP2B1-AS1 in the cerebral I/R injury. We found that the expression of ATP2B1-AS1 was upregulated in both in vitro and in vivo cerebral I/R injury models. Knockdown of ATP2B1-AS1 increased the cell viability, inhibited apoptosis, and decreased the expressions of inflammation cytokines. The target of ATP2B1-AS1 was predicted and validated to be miR-330-5p. MiR-330-5p abrogated the regulatory effect of ATP2B1-AS1 on cell viability, apoptosis, and cytokines of OGD/R PC12 cells. Furthermore, the results showed that miR-330-5p targeted TLR4, which was also upregulated in the infarcted area of MCAO/IR rats and OGD/R PC12 cells. Overexpression of ATP2B1-AS1 increased the expressions of TLR4, MyD88, and NF-κB p65 of OGD/R PC12 cells, while the effect of ATP2B1-AS1 was abrogated by miR-330-5p. In addition, knockdown of ATP2B1-AS1 decreased the latency time, increased the time of passing the platform position, reduced the cerebral infarct volume, decreased neurological deficit scores, and reduced the number of damaged neurons of MCAO/IR rats that were subjected to the Morris water maze test. Taken together, our study indicates that ATP2B1-AS1 may be an attractive therapeutic target for the treatment of cerebral ischemic injuries.

LncRNA CASC15 Promotes Cerebral Ischemia/Reperfusion Injury via miR-338-3p/ETS1 Axis in Acute Ischemic Stroke

Purpose

Acute ischemic stroke (AIS) is a leading health problem caused by cerebral ischemia/reperfusion (CI/R). This study aimed to unveil the potential clinical value and mechanism of lncRNA CASC15.

Patients and Methods

The expression of CASC15, miR-338-3p was detected by quantitative real-time PCR (qRT-PCR). The correlations between CASC15 and national institutes of health stroke scale (NIHSS) scores or miR-338-3p were evaluated by Pearson correlation. A receiver operating characteristic (ROC) curve was performed to provide the diagnostic value of CASC15. Cell Counting Kit-8 (CCK-8) and flow cytometer were used to detect the condition of cell viability and apoptosis. The levels of interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) was detected by enzyme-linked immunosorbent assay (ELISA) assay.

Results

The expression of CASC15 was increased and the levels of miR-338-3p were decreased in AIS patients. A positive association between CASC15 and NIHSS score and an inverse association between CASC15 and miR-338-3p were revealed by Pearson correlation. CASC15 might discriminate AIS patients from healthy people. Silenced CASC15 exerted neuroprotective roles on cell viability, apoptosis, and inflammation via the miR-338-3p/ETS1 axis.

Conclusion

CASC15 might act as a potential diagnostic biomarker for AIS patients. CASC15/miR-338-3p/ETS1 axis played an essential role in cell viability, apoptosis, and neuroinflammation.

Allicin protects against myocardial I/R by accelerating angiogenesis via the miR-19a-3p/PI3K/AKT axis

Objectives: Allicin is an allyl 2-propenethiosulfinate or diallyl thiosulfinate acid with cardioprotective effects in myocardial ischemia/reperfusion (MI/R) injury. This study aims to examine the underlying mechanism by which Allicin protects against MI/R.

Methods: C57BL6 mice were subjected to either sham or MI/R surgery, and mice in the Allicin group were injected with Allicin (5 mg/ml) before the induction of ischemia. The cardiac function and histopathology of experimental mice were evaluated by ultrasound quantification and Masson staining. We next measured the capillary angiogenesis of the peri-infarct area by Masson staining and immunohistochemical staining. The miRNA microarray was carried out to examine the expressed miRNAs in MI/R tissues and corresponding normal tissues. Real-time quantitative polymerase chain reaction (q-PCR) was performed to validate the selected miRNA-19α-3p gene expression. Besides, we evaluated the myocardial lactate dehydrogenase and COX-2 by immunofluorescence staining. The western blot analysis was used to evaluate the protein levels of p-AKT, p-PI3K, p-mTOR, COX-2, and VEGF protein in the Allicin and Model group. In vitro study, LPS stimulated Tie2 expressing macrophages were cultured in an ischemic buffer. We evaluated the accumulation of VEGF by fura-2/AM fluorescence. Besides, Western blotting was performed to examine the protein levels of p-PI3K, p-AKT, p-mTOR, VEGF, COX2, and MMP2. The PI3K inhibitor was applied to investigate whether Allicin-induced myocardial ischemia-reperfusion injury protection is mediated via the PI3K/AKT pathway. And the miR-19α-3p mimic/inhibitor were transfected to promote/inhibit the expression of miR-19a-3p for verifying the regulation of miR-19a-3p on PI3K pathway.

Results: Allicin pretreatment significantly improved I/R-induced cardiac function damage. Furthermore, Allicin could repress cardiac fibrosis, as evidenced by reduced areas of cardiac fibrosis. Allicin’s effect on the MI/R was associated with increased capillary angiogenesis. Microarray analysis exposed that miR-19a-3p down-regulated PIK3CA (PI3K) expression by directly targeting the PIK3CA gene. The regulation of the angiogenesis pathway and gene miRNA-19a-3p might affect the Allicin-induced MI/R protection. Immunofluorescence staining revealed that COX-2 and myocardial lactate dehydrogenase were significantly increased after Allicin treatment. Furthermore, western blot analysis demonstrated that p-AKT, p-PI3K, p-mTOR, COX-2, and VEGF protein levels were also increased in the Allicin group. In vitro study, the protein levels of p-PI3K, p-AKT, p-mTOR, VEGF, COX2, and MMP2 were significantly increased in the Allicin-treated Tie2 expressing macrophages. These effects were partially reversed by PI3K inhibitor (Wortmannin) treatment. MiR-19α-3p plays an important role in myocardial I/R injury. It could regulate the activity of the PI3K-AKT pathway. And inhibition of miR-19a-3p promoted angiogenesis by regulating PI3K/AKT pathway.

Conclusions: Allicin pretreatment protects against myocardial I/R and activating the miR-19a-3p/PI3K/AKT pathway.

lncRNA AC007207.2 Promotes Malignant Properties of Osteosarcoma via the miR-1306-5p/SIRT7 Axis

Background

Long non-coding RNAs (lncRNAs) have been implicated in initiation and development of numerous cancers. In the present study, we explored the role of lncRNAs AC007207.2 in osteosarcoma (OS).

Methods

Gene expression data of OS tissues was downloaded from the TARGET database. All the experiments were repeated at least three times. Data were analyzed using Perl, R, SPSS v12.0 and GraphPad Prism 8 software.

Results

We found lncRNA AC007207.2 was over-expressed in OS tissues and cell lines, and this phenomenon was associated with the worse prognosis of OS. Moreover, we found that AC007207.2 promotes proliferation and metastasis of OS cells via the miR-1306-5p/SIRT7 axis. Meanwhile, we found miR-1306-5p remarkably inhibits the malignant behavior of OS cells.

Conclusion

lncRNA AC007207.2 promotes progression of OS by upregulating SIRT7 expression through miR-1306-5p sponging. Thus, lncRNA AC007207.2/miR-1306-5p/SIRT7 axis is a promising therapeutic target for OS treatment.

Overexpression of miR-149-5p Attenuates Cerebral Ischemia/Reperfusion (I/R) Injury by Targeting Notch2

Ischemic stroke is one of the leading causes of death and disability worldwide. Although miR-149-5p downregulation is observed in rats after ischemia/reperfusion (I/R) injury, its function and role in ischemic stroke remain unclear. This study aimed to investigate the roles of miR-149-5p in I/R injury. The results showed that miR-149-5p was significantly downregulated in brain tissues of rats subjected to middle cerebral artery occlusion (MCAO) and primary cortical neurons subject to oxygen and glucose deprivation (OGD). MiR-149-5p overexpression effectively reduced MCAO/R-induced infarct volume, neurological score, and brain water content as well as OGD/R-induced cortical neurons apoptosis and OGD/R-induced expression of TNF-α, IL-4, IL-6, IL-1β, and COX-2. Moreover, Notch2 was identified as a target of miR-149-5p and Notch2 overexpression significantly attenuated the inhibitory effects of miR-149-5p mimics on inflammation and apoptosis. Taken together, our study revealed that miR-149-5p overexpression protects the rat brain against I/R injury by regulating Notch2-mediated inflammation and apoptosis pathway.

Dysregulation Serum miR-19a-3p is a Diagnostic Biomarker for Asymptomatic Carotid Artery Stenosis and a Promising Predictor of Cerebral Ischemia Events

This study aims to identify the diagnostic potential of microRNA-19a-3p (miR-19a-3p) for asymptomatic carotid artery stenosis (CAS) and clinical predictive potential for cerebral ischemia events (CIEs). Serum samples from 101 asymptomatic CAS patients and 98 healthy controls were collected. And it was found that serum miR-19a-3p in asymptomatic CAS patients was generally elevated (P < .05). Increased miR-19a-3p in asymptomatic CAS was associated with severe CAS (odds ratio  = 3.920, 95% confidence interval [CI] = 1.482-10.372, P < .01). The area under the receiver operating characteristic (ROC) curve (AUC) was 0.905, indicating that the level of miR-19a-3p was statistically significant for the diagnosis of asymptomatic CAS. Furthermore, the level of serum miR-19a-3p (hazard ratio [HR] = 8.507, 95% confidence interval [CI] = 2.239-32.328, P = .002) and degree of artery stenosis (HR = 3.695, 95% CI = 1.127-12.109, P = .031) were independent predictors of occurrence of CIE. Moreover, patients with elevated miR-19a-3p levels were more likely to experience CIE than patients with low levels. Upregulated miR-19a-3p can be used as a diagnostic biomarker for asymptomatic CAS patients and as an independent predictor of CIE.

Retracted: Bone marrow mesenchymal stem cells-derived extracellular vesicles carrying microRNA-221-3p protect against ischemic stroke via ATF3

OBJECTIVE

We aim to explore the protective effect of bone marrow mesenchymal stem cells (BMSCs)-derived exosomal microRNA-221-3p (miR-221-3p) on ischemic stroke (IS) by targeting activating transcription factor 3 (ATF3).

METHODS

The middle cerebral artery occlusion (MCAO) mice model and oxygen-glucose deprivation (OGD) neuron model were established. Extracellular vesicles were isolated from BMSCs (BMSC-EVs) and transfected with altered miR-221-3p or ATF3 to treat the MCAO mice and OGD-treated neurons. MiR-221-3p and ATF3 expression were determined, and the contents of inflammatory factors were detected. The pathological changes and apoptosis in mice brain tissues were observed. In cellular experiments, the viability and apoptosis of OGD-treated neurons were evaluated. Binding relationship between miR-221-3p and ATF3 was determined.

RESULTS

MiR-221-3p was down-regulated and ATF3 was up-regulated in MCAO mice and OGD-treated neurons. BMSC-EVs and BMSC-EVs carrying up-regulated miR-221-3p attenuated inflammation, pathological changes and apoptosis in MCAO mice brain tissues, and also promoted viability and repressed apoptosis of OGD-treated neurons. ATF3 was verified as a target of miR-221-3p.

CONCLUSION

BMSC-EVs carrying miR-221-3p protect against IS by inhibiting ATF3. This study may be helpful for exploring therapeutic strategies of IS.

Relevant mediators involved in and therapies targeting the inflammatory response induced by activation of the NLRP3 inflammasome in ischemic stroke

The nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome is a member of the NLR family of inherent immune cell sensors. The NLRP3 inflammasome can detect tissue damage and pathogen invasion through innate immune cell sensor components commonly known as pattern recognition receptors (PRRs). PRRs promote activation of nuclear factor kappa B (NF-κB) pathways and the mitogen-activated protein kinase (MAPK) pathway, thus increasing the transcription of genes encoding proteins related to the NLRP3 inflammasome. The NLRP3 inflammasome is a complex with multiple components, including an NAIP, CIITA, HET-E, and TP1 (NACHT) domain; apoptosis-associated speck-like protein containing a CARD (ASC); and a leucine-rich repeat (LRR) domain. After ischemic stroke, the NLRP3 inflammasome can produce numerous proinflammatory cytokines, mediating nerve cell dysfunction and brain edema and ultimately leading to nerve cell death once activated. Ischemic stroke is a disease with high rates of mortality and disability worldwide and is being observed in increasingly younger populations. To date, there are no clearly effective therapeutic strategies for the clinical treatment of ischemic stroke. Understanding the NLRP3 inflammasome may provide novel ideas and approaches because targeting of upstream and downstream molecules in the NLRP3 pathway shows promise for ischemic stroke therapy. In this manuscript, we summarize the existing evidence regarding the composition and activation of the NLRP3 inflammasome, the molecules involved in inflammatory pathways, and corresponding drugs or molecules that exert effects after cerebral ischemia. This evidence may provide possible targets or new strategies for ischemic stroke therapy.

MicroRNA-532-5p protects against cerebral ischemia-reperfusion injury by directly targeting CXCL1

We investigated the function of microRNA (miR)-532-5p in cerebral ischemia-reperfusion injury (CI/RI) and the underlying mechanisms using oxygen-glucose deprivation and reperfusion (OGD/R)-treated SH-SY5Y cells and middle cerebral artery occlusion (MCAO) model rats. MiR-532-5p levels were significantly downregulated in OGD/R-treated SH-SY5Y cells and the brain tissues of MCAO model rats. MiR-532-5p overexpression significantly reduced apoptosis, reactive oxygen species (ROS), and inflammation in the OGD/R-induced SH-SY5Y cells. Bioinformatics analysis using the targetscan and miRDB databases as well as dual luciferase reporter assays confirmed that miR-532-5p directly binds to the 3’UTR of C-X-C Motif Ligand 1 (CXCL1). Methylation-specific PCR (MSP) analysis showed that miR-532-5p expression was reduced in OGD/R-treated SH-SY5Y cells because of miR-532-5p promoter hypermethylation. Moreover, 5-azacytidine, a methylation inhibitor, restored miR-532-5p expression in OGD/R-treated SH-SY5Y cells. Brain tissues of MCAO model rats showed significantly increased cerebral infarction areas, cerebral water, neuronal apoptosis, and activated CXCL1/CXCR2/NF-κB signaling, but these effects were alleviated by intraventricular injection of miR-532-5p agomir. These findings demonstrate that miR-532-5p overexpression significantly reduces in vitro and in vivo CI/RI by targeting CXCL1. Thus, miR-532-5p is a potential therapeutic target for patients with CI/RI.

Down-Regulation of miR-181a-5p Prevents Cerebral Ischemic Injury by Upregulating En2 and Activating Wnt/β-catenin Pathway

PURPOSE

Cerebral ischemic injury contributes to severe dysfunction of the brain, which triggers extremely high mortality and disability. The role of microRNA (miR)-181a-5p is documented in cerebral ischemic injury. Therefore, this study intended to further figure out the mechanism of miR-181a-5p in cerebral ischemic injury.

METHODS

miR-181a-5p expression in middle cerebral artery occlusion (MCAO) mouse model, oxygen-glucose-deprivation/reoxygenation (OGD/R) N2a cell model, and serum from acute ischemic injury (ACI) patients was evaluated using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Gain- and loss-of-function assays were implemented in MCAO mice and OGD/R-induced N2a cells. In mice, the cerebral infarction area was assessed with 2,3,5-triphenyltetrazolium chloride staining, the number of damaged neurons by Nissl staining, and apoptosis by TdT-mediated dUTP-biotin nick end-labeling staining. Moreover, N2a cell apoptosis and proliferation were determined with flow cytometry or 5-ethynyl-2'-deoxyuridine staining, respectively. The expression of En2 and Wnt/β-catenin pathway-related factors was determined with RT-qPCR and Western blot analysis. The targeting relationship between miR-181a-5p and En2 was evaluated by dual luciferase reporter gene assay.

RESULTS

miR-181a-5p was highly expressed in serum of ACI patients, MCAO mice, and OGD/R-induced N2a cells. En2, lowly expressed in MCAO mice, was targeted by miR-181a-5p, and miR-181a-5p down-regulation activated the Wnt/β-catenin pathway. Furthermore, miR-181a-5p inhibition or En2 overexpression reduced cerebral infarction area, the number of damaged neurons, and apoptosis in MCAO mice, and also diminished apoptosis and accelerated proliferation of OGD/R-induced N2a cells.

CONCLUSION

miR-181a-5p suppression activated Wnt/β-catenin pathway and sequentially attenuated cerebral ischemic injury by targeting En2.

Inhibition of miR-448-3p Attenuates Cerebral Ischemic Injury by Upregulating Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2)

BACKGROUND

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key regulator responsible for oxidative stress in brain injury. This study aimed to investigate the potential mechanism of miR-448-3p and Nrf2 in cerebral ischemia/reperfusion (I/R) injury.

METHODS

In vitro and in vivo cerebral I/R injury models were constructed, and Nrf2 expression levels were detected by qRT-PCR and Western blot. The potential miRNAs for Nrf2 were predicted by bioinformatic analysis. The binding interaction between miR-448-3p and Nrf2 was determined by luciferase reporter assay. The effects of miR-448-3p on neurological deficit, infarct volume, and brain water content in mice were tested. The effects of miR-448-3p on oxidative stress indicators (SOD activity, MDA content, and ROS production) were detected by commercial assay kits. The levels of HO-1 and cleaved caspase-3 were evaluated by Western blot. Cell viability was evaluated by MTT assay, and cell apoptosis was evaluated by TUNEL staining and flow cytometry.

RESULTS

Nrf2 was significantly downregulated and miR-448-3p was upregulated in cerebral I/R injury both in vivo and in vitro. MiR-448-3p downregulation efficiently attenuated brain injury and reduced oxidative stress and apoptosis. MiR-448-3p was identified to act as ceRNA of Nrf2 and negatively regulated Nrf2 expression, which was consistent with the animal studies. In addition, Nrf2 silencing obviously attenuated the neuroprotective effects of miR-448-3p inhibitor in vitro.

CONCLUSION

MiR-448-3p participated in the regulation of cerebral I/R injury via inhibiting Nrf2.

Biliverdin Protects Against Cerebral Ischemia/Reperfusion Injury by Regulating the miR-27a-3p/Rgs1 Axis

BACKGROUND

We have previously demonstrated that biliverdin has neuroprotective effects that ameliorate cerebral ischemia/reperfusion (I/R) injury in rats. However, the underlying mechanism is unknown. This study aimed at elucidating on the modulatory role of miR-27a-3p on Rgs1 as a mechanism by which biliverdin affects cerebral I/R injury.

METHODS

Middle cerebral artery occlusion/reperfusion (MCAO/R) was used to establish I/R rat models while oxygen glucose deprivation/reoxygenation (OGD/R) was used to induce hippocampal neurons to establish I/R models in vitro. Infarct volume was assessed by TTC staining. Apoptotic analyses of ischemic cortical neurons and cells were performed by TUNEL staining and flow cytometry, respectively. Cell viability was assessed by the CCK-8 assay while the target of miR-27a-3p was determined by double luciferase reporter assay. Relative expression levels of miR-27a-3p and Rgs1 (in vivo and in vitro) as well as markers of inflammation and apoptosis (in vitro) were detected by RT-qPCR. Then, Elisa and western blot were used to assess protein expression levels of inflammatory and apoptotic markers in vitro.

RESULTS

Biliverdin suppressed inflammation and apoptosis in hippocampal neurons upon OGD/R, and reduced cerebral infarction volume as well as apoptosis in the MCAO/R rat model. Furthermore, biliverdin upregulated miR-27a-3p and downregulated hippocampal neuron Rgs1 after OGD/R as well as in rat brain tissues after cerebral I/R. Bioinformatic analysis revealed an miR-27a-3p docking site in the 3'-UTR region of Rgs1. Luciferase reporter assays showed that Rgs1 is an miR-27a-3p target. Moreover, miR-27a-3p upregulation inhibited OGD/R-triggered inflammation and suppressed neuronal apoptosis. Rgs1 knockdown suppressed OGD/R-triggered inflammation and decreased neuronal apoptosis while miR-27a-3p downregulation reversed the protective effect of Rgs1 knockdown. Moreover, miR-27a-3p overexpression and Rgs1 silencing suppressed NF-κB (p65) expression.

CONCLUSION

Biliverdin protects against cerebral I/R injury by regulating the miR-27a-3p/Rgs1 axis, thereby inhibiting inflammation and apoptosis.

MiR-195-5p Ameliorates Cerebral Ischemia-Reperfusion Injury by Regulating the PTEN-AKT Signaling Pathway

BACKGROUND

MiR-195-5p has been shown to play crucial roles in tumor inhibition, but its biological functions in cerebral ischemia-reperfusion (I/R) injury are unclear.

METHODS

To mimic cerebral I/R injury, mice were induced by transient middle cerebral artery occlusion (MCAO). Human brain microvascular endothelial cells (HBMVECs) were treated with oxygen-glucose deprivation (OGD) to mimic I/R injury in vitro. The expression of miR-195-5p and PTEN was detected by qRT-PCR or Western blot. Cell viability was evaluated by CCK-8 assay. Cell apoptosis was detected by flow cytometer. Cell death was detected using specific lactate dehydrogenase (LDH) cytotoxicity kit. Infarct volume in mice brains was evaluated by TTC staining. Histopathological analysis was performed by HE staining and TUNEL staining. The interaction between miR-195-5p and PTEN was determined by TargetScan and luciferase reporter assay.

RESULTS

MiR-195-5p was significantly downregulated and PTEN was upregulated during cerebral I/R injury both in vitro and in vivo. Overexpression of miR-195-5p efficiently enhanced cell viability, while reduced LDH release and apoptotic rate of OGD-treated HBMVECs in vitro. MiR-195-5p could negatively regulate the expression of PTEN by directly binding to its 3'-UTR. Overexpression of PTEN obviously attenuated the protective effect of miR-195-5p mimics on cell viability, LDH release and apoptosis in OGD-treated HBMVECs. Meanwhile, overexpression of miR-195-5p increased the expression levels of p-AKT in OGD-treated HBMVECs, while this effect was reversed by overexpression of PTEN. Moreover, overexpression of miR-195-5p efficiently ameliorated brain injury of mice after MCAO treatment in vivo.

CONCLUSION

Overexpression of miR-195-5p ameliorated cerebral I/R injury by regulating the PTEN-AKT signaling pathway, providing a potential therapeutic target for cerebral I/R injury.

Inhibition of microRNA-9-5p and microRNA-128-3p can inhibit ischemic stroke-related cell death in vitro and in vivo

Ischemic stroke is the major form of stroke and is accentuated by multiple comorbidities. It has been previously shown that different microRNAs (miRNAs) regulate separate aspects of ischemic stroke. Differential miRNA expression analysis in cerebrospinal fluid of stroke patients had revealed upregulation of miR-124-3p, miR-9-3p, miR-9-5p, and miR-128-3p. However, whether the overexpression is correlative or causative was not known. Here, using an in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) neuronal cell model, we saw OGD/R-induced injury was associated with significant upregulation of the aforementioned four miRNAs. Target gene prediction using in situ algorithms and gene set enrichment analysis revealed significant enrichment of FOXO and Relaxin signaling pathways and regulatory processes associated with endothelial cell migration, which are all known to associate with apoptotic pathways. In situ protein-protein interaction network analysis confirmed the findings of gene set enrichment analysis. TUNEL analysis showed that OGD/R-induced injury resulted in significant apoptosis, which was significantly inhibited in neuronal cells pretransfected with inhibitors of either miR-9-5p or miR-128-3p. Further testing in an in vivo middle cerebral artery occlusion (MCAO) mouse model of ischemic stroke showed that inhibiting miR-9-5p or miR-128-3p significantly decreases MCAO-induced infraction volume and inhibited apoptotic response as revealed by decreased cleaved Caspase-3 protein expression in immunohistochemical analysis. Combined inhibition of miR-9-5p and miR-128-3p resulted in a synergistic decrease in cell death and infraction volume in vitro and in vivo, respectively. Cumulatively, our results provide critical knowledge about the mechanism by which elevated miR-9-5p and miR-128-3p causes brain damage in ischemic stroke and provides evidence of them being attractive therapeutic targets.

LncRNA MACC1-AS1 attenuates microvascular endothelial cell injury and promotes angiogenesis under hypoxic conditions via modulating miR-6867-5p/TWIST1 in human brain microvascular endothelial cells

Background

Hypoxia following ischemic stroke is a common cause of brain insults. Mounting evidence suggests that long non-coding RNAs (lncRNAs) play a vital role in regulating certain physiological and pathological processes including ischemic stroke. For the first time, the present study investigated the effects and mechanism of LncRNA MACC1-AS1 on hypoxia-induced human brain microvascular endothelial cells (HBMECs).

Methods

LncRNA MACC1-AS1 levels in HBMECs were detected via reverse transcription quantitative polymerase chain reaction (RT-qPCR) assay. Reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT), were detected using their respective kits. Flow cytometry and clone formation assay were performed to evaluate the effects of lncRNA MACC1-AS1 on cell apoptosis and cell proliferation respectively. Angiogenesis capacity was evaluated via tube formation assay. Transwell migration assay was performed for assessment of cell migration, Western blot assay was performed for measurement of Twist1 and VE-cadherin level, and permeability assay was performed for evaluation of the cell barrier function. The target gene was predicted via bioinformatics online tool and validated through luciferase reporter assay and RNA pull-down assay.

Results

LncRNA MACC1-AS1 was downregulated in hypoxia-induced HBMECs. Overexpression of LncRNA MACC1-AS1 reduced cell apoptosis and oxidative stress, while promoting cell proliferation, migration, and angiogenesis. Moreover, LncRNA MACC1-AS1 overexpression reduced cell permeability and elevated VE-cadherin level, which contributed to maintaining cell barrier function. TWIST1 was validated as the target of miR-6867-5p which was further targeted by lncRNA MACC1-AS1. Thus, LncRNA MACC1-AS1 functions in hypoxia-induced HBMECs by regulating miR-6867-5p/TWIST1.

Conclusions

In this study, we found that LncRNA MACC1-AS1 exerted a protective role in hypoxia-induced HBMECs via regulating miR-6867-5p/TWIST1, indicating a new therapeutic strategy for future ischemic stroke therapy.