MiR-101 Protects Against the Cerebral I/R Injury Through Regulating JAK2/STAT3 Signaling Pathway

The dynamic transcriptomic response of the goldfish brain under chronic hypoxia

Oxygen is essential to fuel aerobic metabolism. Some species evolved mechanisms to tolerate periods of severe hypoxia and even anoxia in their environment. Among them, goldfish (Carassius auratus) are unique, in that they do not enter a comatose state under severely hypoxic conditions. There is thus significant interest in the field of comparative physiology to uncover the mechanistic basis underlying hypoxia tolerance in goldfish, with a particular focus on the brain. Taking advantage of the recently published and annotated goldfish genome, we profile the transcriptomic response of the goldfish brain under normoxic (21 kPa oxygen saturation) and, following gradual reduction, constant hypoxic conditions after 1 and 4 weeks (2.1 kPa oxygen saturation). In addition to analyzing differentially expressed protein-coding genes and enriched pathways, we also profile differentially expressed microRNAs (miRs). Using in silico approaches, we identify possible miR-mRNA relationships. Differentially expressed transcripts compared to normoxia were either common to both timepoints of hypoxia exposure (n = 174 mRNAs; n = 6 miRs), or exclusive to 1-week (n = 441 mRNAs; n = 23 miRs) or 4-week hypoxia exposure (n = 491 mRNAs; n = 34 miRs). Under chronic hypoxia, an increasing number of transcripts, including those of paralogous genes, was downregulated over time, suggesting a decrease in transcription. GO-terms related to the vascular system, oxidative stress, stress signalling, oxidoreductase activity, nucleotide- and intermediary metabolism, and mRNA posttranscriptional regulation were found to be enriched under chronic hypoxia. Known 'hypoxamiRs', such as miR-210-3p/5p, and miRs such as miR-29b-3p likely contribute to posttranscriptional regulation of these pathways under chronic hypoxia in the goldfish brain.

Investigating the association between the tissue expression of miRNA-101, JAK2/STAT3 with TNF-α, IL-6, IL-1β, and IL-10 cytokines in the ulcerative colitis patients

BACKGROUND

Ulcerative colitis (UC) is a chronic inflammatory bowel disease caused by numerous factors, such as immune system dysfunction and genetic factors. MicroRNAs (miRNAs) play a crucial role in UC pathogenesis, particularly via the JAK-STAT pathway. Our aim was to investigate the association between miRNA-101 and JAK2-STAT3 signaling pathway with inflammatory cytokines in UC patients.

METHODS

We enrolled 35 UC patients and 35 healthy individuals as the control group, referred to Shariati Hospital, Tehran, Iran. Patients were diagnosed based on clinical, laboratory, histological, and colonoscopy criteria. RNA and protein extracted from tissue samples. Real-time PCR was used to assess the expression levels of miRNA-101, interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-10 genes, while western blot was employed to measure levels of P-STAT3, total STAT3, and JAK2 proteins.

RESULTS

Expression of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 significantly increased, while the expression of IL-10 significantly decreased in the case group versus controls. Additionally, miRNA-101 expression was significantly higher in UC patients. A significant correlation between miRNA-101 and IL-6 expression was observed, indicating their relationship and possible impact on cell signaling pathways, JAK2-STAT3. No significant changes were observed in phosphorylated and total STAT3 and JAK2 protein expression.

CONCLUSION

This study provides evidence of increased miRNA-101 expression in UC tissue, suggesting a potential correlation between miRNA-101 and IL-6 expression and their involvement in the JAK2-STAT3 pathway. The study confirms alterations in UC patients' pro-inflammatory cytokines and anti-inflammatory IL-10. However, further investigations are needed to understand the exact role of miRNA-101 in UC pathogenesis fully.

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.

Regulation of rat HspB5/alphaB-Crystallin by microRNAs miR-101a-3p, miR-140-5p, miR-330-5p, and miR-376b-3p

HspB5/alphaB-crystallin is an ubiquitously expressed member of the small heat shock protein family which help cells to survive cellular stress conditions and are also implicated in neurodegenerative diseases. MicroRNAs are small non-coding RNAs fine-tuning protein expression mainly by inhibiting the translation of target genes. Our earlier finding of an increase in HspB5/alphaB-crystallin protein amount after heat shock in rat hippocampal neurons without a concomitant increase of mRNA prompted us to look for microRNAs as a posttranscriptional regulatory mechanism. Microarray miRNA expression data of rat hippocampal neurons under control and stress conditions in combination with literature search, miRNA binding site prediction and conservation of target sites yielded nine candidate microRNAs. Of these candidates, five (miR-101a-3p, miR-129-2-3p, miR-330-5p, miR-376b-3p, and miR-491-5p) were able to convey a downregulation by binding to the HspB5 3'- or 5'-UTR in a luciferase reporter gene assay while one (miR-140-5p) led to an upregulation. Overexpression of these six microRNAs in C6 glioma cells showed that three of them (miR-101a-3p, miR-140-5p, and miR-376b-3p) regulated endogenous HspB5 protein amount significantly in the same direction as in the reporter gene assay. In addition, overexpression of miR-330-5p and miR-491-5p in C6 cells resulted in regulation of HspB5 in the opposite direction as expected from the luciferase assay. Analysis of miRNA expression in rat hippocampal neurons after cellular stress by qPCR showed that miR-491-5p was not expressed in these cells. In total, we therefore identified four microRNAs, namely miR-101a-3p, miR-140-5p, miR-330-5p, and miR-376b-3p, which can regulate rat HspB5 directly or indirectly.

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.

Overexpression of Circ_0005585 Alleviates Cerebral Ischemia Reperfusion Injury via Targeting MiR-16-5p

Circular RNAs are implicated in the pathogenesis of ischemic stroke. In this work, we explored the modulation and potential mechanisms of action of circ_0005585 in ischemic stroke. Expression of circ_0005585 and miR-16-5p was assessed by quantitative real-time reverse transcription PCR. Ischemic stroke was modeled in mice by middle cerebral artery occlusion (MCAO). The infarct volume was assessed by triphenyl tetrazolium chloride staining. Neurological deficits were evaluated according to Neurological Severity Score. The permeability of the blood-brain barrier was assessed by Evan's blue leakage and brain water content. Apoptosis in brain tissues was measured by the TUNEL test. Relative expression of apoptosis-related proteins was evaluated by Western blotting. The direct interaction between circ_0005585 and miR-16-5p was verified by dual-luciferase reporter assay. The expression of circ_0005585 was lower in mice with MCAO. Lentivirus-mediated overexpression of circ_0005585 ameliorated the neurological deficits and decreased the infarction volume in MCAO mice. The brain water content and Evan's blue leakage through the blood-brain barrier were reduced. In addition, overexpression of circ_0005585 inhibited apoptosis in the cerebral tissues. Our results revealed direct interaction between circ_0005585 and miR-16-5p. Hence, circ_0005585 protects mouse brain during ischemic stroke by targeting miR-16-5p, which uncovers the pathogenesis of this pathology and opens new vitas for its therapy.

RGD1564534 represses NLRP3 inflammasome activity in cerebral injury following ischemia-reperfusion by impairing miR-101a-3p-mediated Dusp1 inhibition

BACKGROUND

Mitochondrial autophagy, the elimination of damaged mitochondria through autophagy, contributes to neuron survival in cerebral ischemia. Long non-coding RNAs (lncRNAs)/microRNAs (miRNAs)/mRNAs are important regulatory networks implicated in various biological processes, including cerebral ischemia-reperfusion (I/R) injury. Therefore, this work clarifies a novel RGD1564534-mediated regulatory network on mitochondrial autophagy in cerebral I/R injury.

METHODS

Differentially expressed lncRNAs in cerebral I/R injury were predicted by bioinformatics analysis. Expression of RGD1564534 was examined in the established middle cerebral artery occlusion (MCAO) rats and oxygen glucose deprivation/reoxygenation (OGD/R)-exposed neurons. We conducted luciferase activity, RNA pull-down and RIP assays to illustrate the interaction among RGD1564534, miR-101a-3p and Dusp1. Gain- or loss-of-function approaches were used to manipulate RGD1564534 and Dusp1 expression. The mechanism of RGD1564534 in cerebral I/R injury was evaluated both in vivo and in vitro.

RESULTS

RGD1564534 was poorly expressed in the MCAO rats and OGD/R-treated cells, while its high expression attenuated nerve damage, cognitive dysfunction, brain white matter and small vessel damage in MCAO rats. In addition, RGD1564534 promoted mitochondrial autophagy and inhibited NLRP3 inflammasome activity. RGD1564534 competitively bound to miR-101a-3p and attenuated its binding to Dusp1, increasing the expression of Dusp1 in neurons. By this mechanism, RGD1564534 enhanced mitochondrial autophagy, reduced NLRP3 inflammasome activity and suppressed the neuron apoptosis induced by OGD/R.

CONCLUSION

Altogether, RGD1564534 elevates the expression of Dusp1 by competitively binding to miR-101a-3p, which facilitates mitochondrial autophagy-mediated inactivation of NLRP3 inflammasome and thus retards cerebral I/R injury.

Circ_0000011 promotes cerebral ischemia/reperfusion injury via miR-27a-3p-dependent regulation of NRIP1

BACKGROUND

Cerebral ischemia/reperfusion (I/R) can result in brain function impairments. Circular RNAs (circRNAs) have emerged as vital regulators in cerebral I/R injury. However, the functions of mmu_circ_0000011 in cerebral I/R injury are still unclear. Thus, in this study, we aimed to explore the effect of mmu_circ_0000011 on cerebral I/R injury.

METHODS

Oxygen-glucose deprivation and reperfusion (OGD/R)-induced HT-22 cells were used to mimic the condition of cerebral I/R injury in vitro. Cell Counting Kit-8 (CCK-8) assay, lactate dehydrogenase (LDH) assay, 5'-ethynyl-2'-deoxyuridine (EdU) assay and flow cytometry analysis were utilized to assess cell viability, LDH release, proliferation and apoptosis, respectively. qRT-PCR and western blot were performed to determined the levels of circ_0000011, miR-27a-3p and NRIP1. Dual-luciferase reporter assay and RNA pull-down assay were utilized to analyze the targeting relation of circ_0000011, miR-27a-3p and NRIP1.

RESULTS

OGD/R treatment inhibited HT-22 cell viability and promoted LDH release, cell apoptosis and inflammation. Circ_0000011 level was increased in OGD/R-induced HT-22 cells. Silencing of circ_0000011 promoted cell proliferation and inhibited LDH release, apoptosis and inflammation in OGD/R-treated HT-22 cells. For mechanism analysis, circ_0000011 was demonstrated to sponge miR-27a-3p, which directly targeted NRIP1. MiR-27a-3p inhibition or NRIP1 overexpression ameliorated the impacts of circ_0000011 silencing on cell proliferation, LDH release, apoptosis and inflammation in OGD/R-treated HT-22 cells.

CONCLUSIONS

Circ_0000011 promotes OGD/R-induced HT-22 cell impairments by elevating NRIP1 through sponging miR-27a-3p.

Artesunate regulates the proliferation and differentiation of neural stem cells by activating the JAK‑2/STAT‑3 signaling pathway in ischemic stroke

Ischemic stroke is one of the most common causes of disability and death globally; therefore, the repair and reconstruction of the central nervous system (CNS) after stroke is very important. Neural stem/progenitor cells (NSPCs) may be the key to cell replacement therapy to treat CNS damage. It has previously been reported that artesunate (ART) is involved in the regulation of the biological functions of NSPCs; however, the mechanism of action of ART remains unclear. In the present study, different concentrations of ART were used to treat NSPCs following oxygen-glucose deprivation (OGD). Cell viability and apoptosis were analyzed using Cell Counting Kit-8 assay and flow cytometry, respectively, whereas immunofluorescence analysis was used to measure the expression levels of the differentiation-related molecule doublecortin (DCX) and proliferating cell nuclear antigen (PCNA). Western blotting was performed to analyze the expression levels of molecules related to the JAK-2/STAT-3 signaling pathway. The present results indicated that treatment with ART following OGD significantly promoted the viability of NSPCs, inhibited the apoptosis of NSPCs, and promoted the expression of PCNA and DCX. Moreover, ART significantly downregulated the protein expression levels of phosphorylated (p)-JAK-2 and p-STAT-3. Furthermore, activation of the JAK-2/STAT-3 signaling pathway and treatment with ART reversed the effects of ART on the proliferation, apoptosis and differentiation of NSPCs. In conclusion, the present data suggested that ART may promote the proliferation and differentiation of NSPCs, and reduce the apoptosis of NSPCs, by inhibiting the JAK-2/STAT-3 signaling pathway. ART may potentially be used for the treatment of ischemic stroke.

Relationship between Peripheral Blood miR-181c, miR-101, and Cognitive Impairment in Patients with Diabetes Mellitus Complicated with Acute Stroke

Objectives

To explore the relationship between peripheral blood microRNA-181c (miR-181c), microRNA-101 (miR-101), and cognitive impairment (CI) in patients with diabetes mellitus (DM) complicated with acute stroke (AS).

Methods

A retrospective analysis was performed on 70 patients with DM complicated with AS admitted to the hospital between January 2019 and December 2021. According to presence or absence of CI, they were divided into CI group (41 cases) and non-CI group (29 cases). The clinical characteristics and general data (blood glucose and blood lipid) of patients were statistically analyzed. The relative expression levels of miR-181c and miR-101 in peripheral blood were detected by real-time fluorescence quantitative PCR. The risk factors of CI were analyzed by logistic regression analysis. The diagnostic value of peripheral blood miR-181c and miR-101 for CI was evaluated by receiver operating characteristic (ROC) curves.

Results

The relative expression levels of peripheral blood miR-181c and miR-101 in the CI group were lower than those in the non-CI group (P < 0.05). The occurrence of CI was related to age, course of DM, AS location, time from onset to admission, HbA1c, TG, UA, and Hcy levels (P < 0.05). Logistic regression analysis showed that age, AS location, HbA1c, miR-181c, and miR-101 were related influencing factors of CI in patients with DM complicated with AS (P < 0.05). The results of ROC curves analysis showed that AUC, sensitivity, and specificity of miR-181c combined with miR-101 for predicting CI were 0.865, 73.17%, and 89.66%, respectively (P < 0.05).

Conclusions

The peripheral blood miR-181c and miR-101 are low expressed in patients with DM complicated with AS, and advanced age, intracortical AS lesions, increased HbA1c, and low expression of miR-181c and miR-101 are all independent risk factors for CI in patients with DM complicated with AS. Besides, the combined detection of miR-181c and miR-101 expression has a good diagnostic value for CI.