Yang Xu

Necroptosis is a critical response to secondary brain injury following intracerebral hemorrhage (ICH). Z‐DNA Binding Protein 1 (ZBP1) binds to dsRNA and promotes the activation of Receptor‐Interacting Protein Kinase 3 (RIPK3). This study investigated whether Adenosine Deaminase Acting on RNA 1 (ADAR1) inhibits neuronal necroptosis after ICH. ADAR1‐knockdown mice and ZBP1 ^flox/flox /Thy1‐Cre ^+/− mice were subjected to collagenase VII‐induced ICH. Brain edema and neurobehavioral deficits were assessed. The expressions of ADAR1 and ZBP1 were investigated by qPCR, western blot, immunofluorescence, and ELISA. Protein interactions were performed using co‐immunoprecipitation. ADAR1p150 was reduced in both ICH patients and mice. ZBP1 and ADAR1 both bound to dsRNA. ADAR1p150 suppressed ZBP1 activation, potentially through functional antagonism and dsRNA editing, although causality remains to be established. Knockout of ZBP1 resulted in increased ADAR1p150 expression and reduced brain edema. Etanercept and shRNA‐mediated ADAR1 knockdown promoted ZBP1 expression. Complementation of the ADAR1 Zα truncation did not reduce ZBP1 in ADAR1‐knockdown cells. The inhibitory effect of ADAR1 on ZBP1 was attenuated in ADAR1 ^Zα−/− cells. These data show that the Zα domain is required for ADAR1 to suppress ZBP1, but they do not establish whether this suppression depends on RNA editing or on dsRNA binding alone.

Background: Intracerebral hemorrhage (ICH) causes a severe form of stroke characterized by high morbidity, mortality, and long-term disability. Neuronal cell death is influenced at the posttranscriptional level. Certain microRNAs influence neuronal cell death at the posttranscriptional level by regulating receptor-interacting protein kinase 3 ( RIPK3 ), a key mediator of necroptosis. The specific mechanism by which miR-873 mediates neuronal necroptosis following ICH remains unclear. Epigenetic abnormalities, particularly N6-methyladenosine (m6A) modification, are increasingly recognized as critical contributors to ICH pathophysiology. Methods: ICH mice model was established, followed by intracerebroventricular injection for gene manipulation. Brain water content was measured to assess cerebral edema. Neurological function was evaluated using the Morris water maze and neurological deficit scoring. Molecular and cellular analyses included Western blotting, quantitative real-time PCR, immunofluorescence, and luciferase reporter assays. Primary neuronal cultures, plasmid construction, and m6A RNA methylation quantification were performed to investigate underlying mechanisms. Differential gene expression was analyzed using microarray profiling, and data were statistically evaluated with appropriate analytical methods. Results: The m6A modification is upregulated and positively involved in the functional role of miR-873 in ICH. miR-873 rescued necroptosis in ICH. miR-873 targets RIPK3 . RRACH (R = G or A; H = A, C, or U) m6A sequence motifs predominantly contribute to the m6A modification of miR-873 . The m6A modification regulates necroptosis in ICH. Knockdown of methyltransferase-like 3 improved the neurological function prognosis of ICH in mice. Conclusion: m6A modification modulates miR-873 expression, thereby influencing RIPK3-mediated necroptosis in ICH. These findings provide potential therapeutic targets for mitigating neuronal injury after hemorrhagic stroke.

Background: Necroptosis induced by receptor‐interacting protein kinase 3 (RIPK3) is engaged in intracerebral hemorrhage (ICH) pathology. In this study, we explored the impact of RIPK3 activation on neuronal necroptosis and the mechanism of the death domain‐associated protein (DAXX)‐mediated nuclear necroptosis pathway after ICH.Methods: Potential molecules linked to the progression of ICH were discovered using RNA sequencing. The level of DAXX was assessed by quantitative real‐time PCR, ELISA, and western blotting. DAXX localization was determined by immunofluorescence and immunoprecipitation assays. The RIPK3 inhibitor GSK872 and DAXX knockdown with shRNA‐DAXX were used to examine the nuclear necroptosis pathway associated with ICH. Neurobehavioral deficit assessments were performed.Results: DAXX was increased in patients and mice after ICH. In an ICH mouse model, shRNA‐DAXX reduced brain water content and alleviated neurologic impairments. GSK872 administration reduced the expression of DAXX. shRNA‐DAXX inhibited the expression of p‐MLKL. Immunofluorescence and immunoprecipitation assays showed that RIPK3 and AIF translocated into the nucleus and then bound with nuclear DAXX.Conclusions: RIPK3 revitalization promoted neuronal necroptosis in ICH mice, partially through the DAXX signaling pathway. RIPK3 and AIF interacted with nuclear DAXX to aggravate ICH injury.

MiR-590-3p has been reported to be reduced in myocardial ischaemia-reperfusion (I/R) injury, but its specific role in cerebral I/R injury is still uncertain. Thus, we explored the function and mechanism of miR590-3p in cerebral I/R injury using a cellular model. miR-590-3p, high mobility group Box 1 (HMGB1), and signalling-related factor levels were assessed using qPCR or a western blot analysis. Cell apoptosis was measured by flow cytometry. Inflammatory factors were detected by ELISA. The target of miR-590-3p was confirmed by dual-luciferase reporter assay and western blot analysis. We found that miR-590-3p was decreased and HMGB1 was increased in the OGD/R model. Upregulation of miR-590-3p reduced cell apoptosis and inflammation in the OGD/R model, and the TLR4/MyD88/NF-?B signalling pathway was suppressed. However, inhibition of miR-590-3p showed the opposite effects. Moreover, HMGB1 was verified as a target gene of miR-590-3p. HMGB1 reversed the decrease in apoptosis and inflammation caused by overexpression of miR590-3p, and the TLR4/MyD88/NF-?B signalling pathway was activated. Our results suggest that miR-590-3p regulates the TLR4/MyD88/NF-?B pathway by interacting with HMGB1 to protect against OGD/R-induced I/R injury. Thus, miR-590-3p may serve as a potential therapeutic target in cerebral I/R repair.

Bacterial meningitis after percutaneous radiofrequency trigeminal ganglion is a rare but severe complication. In this article, we report a case of meningitis due to Streptococcus parasanguinis and review the related literature. A 62-year-old male patient with uremia and severe trigeminal neuralgia presented to another hospital and was offered to undergo radiofrequency treatment for a trigeminal ganglion lesion (2022.08.05). The next day (2022.08.06), he presented with a headache and right shoulder and back pain. The pain continued to worsen, so he came to our hospital (The First Affiliated Hospital of Wannan Medical College) and received a diagnosis of bacterial meningitis, which was confirmed by a lumbar puncture. The patient was treated with appropriate antibiotics, and subsequently recovered before being discharged. Although this complication is relatively rare, its progression is rapid. Meningitis must be suspected when a patient presents with headache, fever, and other symptoms associated with meningitis within days after undergoing radiofrequency treatment for a trigeminal ganglion lesion, especially if the patient has an underlying disease that causes a decline in immunity. We discuss this case in terms of clinical presentation, time of onset, treatment, prognosis, past history, and sex. Although early detection of this complication is beneficial, it is better to effectively prevent its occurrence.

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.

Background: Hemorrhagic transformation (HT) is one of the most common and severe complications in patients with acute ischemic stroke (AIS). It indicates a poor prognosis in AIS patients. However, the association of neutrophil to high-density lipoprotein ratio (NHR) with HT remains unclear. Purpose: This study examined whether the NHR has a predictive effect on HT in AIS patients and explored the predictive cutoff value of the NHR. Methods: This is a retrospective study and consecutively included AIS patients admitted to the Department of Neurology of the First Affiliated Hospital of Wannan Medical College between December 2019 and January 2022. All subjects had blood samples collected within 24 h of admission, and neutrophil counts and high-density lipoprotein counts were detected. HT was diagnosed with hemorrhage on subsequent magnetic resonance imaging (MRI) or computed tomography (CT) of the brain. Univariate logistic regression analysis was performed to identify confounding factors, and multivariate logistic regression analysis determined the correlation between NHR and HT. Receiver operating characteristic (ROC) curves were used to evaluate the clinical predictive value of NHR. Results: A total of 725 patients were finally included in this study, of which 87 (12%) developed HT. The median NHR value in the HT group was 4.31, which was significantly higher than that in the non-HT group, and the difference was statistically significant [4.31 (3.54– 6.24) vs 3.63 (2.68– 4.64), p < 0.001]. The binary logistic regression analysis showed that NHR was independently associated with HT in AIS patients (OR: 1.180, 95% CI: 1.036– 1.344, p = 0.013). The area under ROC curve (AUC) of NHR for predicting HT in AIS patients was 0.633 (95% CI: 0.567– 0.699, p < 0.001), and its optimal cutoff were 3.52. Conclusion: The NHR was a reliable and simple independent predictor of HT in AIS patients.

Objective: Dapagliflozin (DAPA) has been reported to have significant cardiac protective effects on heart failure (HF). However, the dose and time, as well as the underlying mechanisms, for DAPA treatment in acute myocardial infarction (AMI) remain controversial. The aim of this study aimed to assess the efficacy and safety of DAPA treatment along with an increased concentration gradient for AMI and explore the potential mechanisms. Methods: Non-diabetic Sprague-Dawley rats were used for establishing AMI models and then were treated with three different concentrations of DAPA [0.5 mg/kg, 1 mg/kg and 1.5 mg/kg, described as AMI+DAPA Low, AMI+DAPA Medium (Med) and AMI+DAPA High, respectively] for six weeks from the onsetting of AMI. Echocardiography, histological staining and Western blot were performed to assess the relevant cardiac protective effects. Mitochondrial biogenesis and myocardial apoptosis were evaluated via the electron microscopy and TUNEL assay, respectively, as well as the Immunoblotting. In vitro, H9c2 cells were subjected to hypoxic treatment to assess the efficacy of DAPA on mitochondrial biogenesis and apoptosis. Results: The medium dose of DAPA treatment could significantly reduce the infarct size (P < 0.01) and the echocardiography results showed that the MI-induced damage in cardiac function got partly repaired, showing no significant difference in left ventricle ejection fraction (LVEF) versus the Sham group (Sham vs AMI+DAPA Med group: 70.47% vs 61.73%). The Western blotting results confirmed the relevant benefits and the underlying mechanisms might be through the activation of PGAM5/Drp1 signaling pathway to normalize the mitochondrial fission and reduce cardiomyocyte apoptosis. Moreover, a medium dose of DAPA treatment could avoid increased damage to the bladder endothelium following higher treatment doses. Conclusion: Appropriate dose of DAPA treatment could improve the cardiac remodeling and reduce the cardiomyocyte apoptosis after AMI, without increased damage to bladder endothelium, which might be more preferred for MI patients without diabetes.