Pathogenesis Of Ischemic Stroke Research Articles

Thrombophilia testing for whom, why and when – a review of current practices

Thromboembolic conditions have accounted for 1 in 4 deaths worldwide in 2010. Thrombosis, which is the common pathogenesis of myocardial infarction, ischaemic stroke, and venous thromboembolism (VTE), is the leading cause of death (1/5 deaths in 1990). Hospital-acquired VTE accounts for approximately 60 percent of all VTEs annually. Others include cancer-associated thrombosis and gender associated risks. In addition to the disease burden, it also causes a significant economic burden world-wide. Multiple diagnostic tests and treatment, prolonged hospital stay and follow-up care, including management of recurrent VTE can be extremely costly. Therefore, it is important to focus on VTE prevention so that health care systems can save money, improve outcomes and save lives. In this background, it is important to have a clear direction as to when, how and whom to test for thrombophilia. Testing for thrombophilias is often performed without a clear understanding of the clinical implications of such results. Guidelines vary in the appropriate use of thrombophilia testing. In this review, these variations in thrombophilia testing and the implications mentioned in the recent guidelines and other articles are discussed. The review of such guidelines, guidance statements, review articles conclude that screening for hereditary thrombophilia has very limited advantage in the management of patients with thrombosis. Screening for antiphospholipid syndrome (APLS) is more important given its high rate of recurrence in both venous and arterial thrombosis. Screening for underlying haematological conditions such as myeloproliferative neoplasms (MPN) and paroxysmal nocturnal haemoglobinuria (PNH) is also considered important.

Comprehensive analysis of lncRNA-miRNA-mRNA ceRNA network in ischemic stroke

ObjectiveCompetitive endogenous RNA (ceRNA) networks have uncovered a novel mode of RNA interaction, and are implicated in various biological processes and the pathogenesis of IS. This study aimed to explore the potential mechanisms underlying the ceRNA network in IS. MethodsFour public datasets containing lncRNA and mRNA (GSE22255 and GSE16561) and miRNA (GSE55937 and GSE43618) expression profiles from the GEO database were systematically analyzed to explore the role of RNAs in ischemic stroke (IS). Differentially expressed mRNAs (DEmRNAs), lncRNAs (DElncRNAs), and miRNAs (DEmiRNAs) between IS and normal control samples were identified. LncRNA-miRNA and miRNA-mRNA interactions were predicted, and the competing endogenous RNA (ceRNA) regulatory network was constructed using the Cytoscape software. The correlation between the RNAs in the ceRNA network and the clinical features of the samples was evaluated. Finally, principal component analysis was performed on the RNAs that constitute the ceRNA regulatory network, and their differential expression and principal component relationships among different types of samples were observed. ResultsA total of 224 DEmRNAs, 7 DEmiRNAs, and four DElncRNAs related to IS in four datasets were identified. Then, through target gene prediction, a lncRNA–miRNA–mRNA ceRNA network that contained 3 DElncRNAs, 2 DEmiRNAs, and 24 DEmRNAs was constructed. Correlations of the clinical characteristics showed that PART1 and SERPINH1 were related to clinical diseases, WNK1 was related to lifestyle, and seven RNAs were related to age. PCA results indicate that three principal components of PC1, PC2, and PC3 can clearly distinguish between control and IS samples. ConclusionOverall, we constructed a ceRNA network in IS, which could offer insights into the molecular mechanism and potential prognostic biomarkers for further research.

Dl-3-n-butylphthalide improves stroke outcomes after focal ischemic stroke in mouse model by inhibiting the pyroptosis-regulated cell death and ameliorating neuroinflammation

Recent studies have highlighted the involvement of pyroptosis-mediated cell death and neuroinflammation in ischemic stroke (IS) pathogenesis. DL-3-n-butylphthalide (NBP), a synthesized compound based on an extract from seeds of Apium graveolens, possesses a broad range of biological effects. However, the efficacy and the underlying mechanisms of NBP in IS remain contentious. Herein, we investigated the therapeutic effects of NBP and elucidated its potential mechanisms in neuronal cell pyroptosis and microglia inflammatory responses. Adult male mice underwent permanent distal middle cerebral artery occlusion (dMCAO), followed by daily oral gavage of NBP (80 mg/kg) for 1, 7, or 21 consecutive days. Gene Expression Omnibus (GEO) dataset of IS patients peripheral blood RNA sequencing was analyzed to identify differentially expressed pyroptosis-related genes (PRGs) during the ischemic process. Our results suggested that NBP treatment effectively alleviated brain ischemic damage, resulting in decreased neurological deficit scores, reduced infarct volume, and improved neurological and behavioral functions. RNA sequence data from human unveiled upregulated PRGs in IS. Subsequently, we observed that NBP downregulated pyroptosis-associated markers at days 7 and 21 post-modeling, at both the protein and mRNA levels. Additionally, NBP suppressed the co-localization of pyroptosis markers with neuronal cells to variable degrees and simultaneously mitigated the accumulation of activated microglia. Overall, our data provide novel evidence that NBP treatment significantly attenuates ischemic brain damage and promotes recovery of neurological function in the early and recovery phases after IS, probably by negatively regulating the pyroptosis cell death of neuronal cells and inhibiting toxic neuroinflammation in the central nervous system.

Analysis of the expression level and predictive value of CLEC16A|miR-654-5p|RARA regulatory axis in the peripheral blood of patients with ischemic stroke based on biosignature analysis.

Ischemic stroke (IS) is a cerebrovascular disease that can be disabling and fatal, and there are limitations in the clinical treatment and prognosis of IS. It has been reported that changes in the expression profile of circRNAs have been found during injury in ischemic stroke, and circRNAs play an important role in the IS cascade response. However, the specific mechanisms involved in the pathogenesis of IS are not yet fully understood, and thus in-depth studies are needed. In this study, one circRNA dataset (GSE161913), one miRNA dataset (GSE60319) and one mRNA dataset (GSE180470) were retrieved from the Gene Expression Omnibus (GEO) database and included, and the datasets were differentially expressed analyzed by GEO2R and easyGEO to get the DEcircRNA, DEmiRNA and DEmRNA, and DEmRNA was enriched using ImageGP, binding sites were predicted in the ENCORI database, respectively, and the competitive endogenous RNA (ceRNA) regulatory network was visualized by the cytoscape software, and then selected by MCC scoring in the cytoHubba plugin Hub genes. In addition, this study conducted a case-control study in which blood samples were collected from stroke patients and healthy medical examiners to validate the core network of ceRNAs constructed by biosignature analysis by real-time fluorescence quantitative qRT-PCR experiments. A total of 233 DEcircRNAs, 132 DEmiRNAs and 72 DEmRNAs were screened by bioinformatics analysis. circRNA-mediated ceRNA regulatory network was constructed, including 148 circRNAs, 43 miRNAs and 44 mRNAs. Finally, CLEC16A|miR-654-5p|RARA competitive endogenous regulatory axis was selected for validation by qRT-PCR, and the validation results were consistent with the bioinformatics analysis. In conclusion, the present study establishes a new axis of regulation associated with IS, providing new insights into the pathogenesis of IS.

Causal effects of gut microbiota on the prognosis of ischemic stroke: evidence from a bidirectional two-sample Mendelian randomization study.

Increasing research has implicated the possible effect of gut microbiota (GM) on the prognosis of ischemic stroke (IS). However, the precise causal relationship between GM and functional outcomes after IS remains unestablished. Data on 211 GM taxa from the MiBioGen consortium and data on prognosis of IS from the Genetics of Ischemic Stroke Functional Outcome (GISCOME) network were utilized as summary-level data of exposure and outcome. Four kinds of Mendelian randomization (MR) methods were carried out to ascertain the causal effect of GM on functional outcomes following IS. A reverse MR analysis was performed on the positive taxa identified in the forward MR analysis to determine the direction of causation. In addition, we conducted a comparative MR analysis without adjusting the baseline National Institute of Health Stroke Scale (NIHSS) of post-stroke functional outcomes to enhance confidence of the results obtained in the main analysis. Four taxa were identified to be related to stroke prognosis in both main and comparative analyses. Specifically, genus Ruminococcaceae UCG005 and the Eubacterium oxidoreducens group showed significantly negative effects on stroke prognosis, while the genus Lachnospiraceae NK4A136 group and Lachnospiraceae UCG004 showed protective effects against stroke prognosis. The reverse MR analysis did not support a causal role of stroke prognosis in GM. No evidence of heterogeneity, horizontal pleiotropy, and outliers was found. This MR study provided evidence that genetically predicted GM had a causal link with post-stroke outcomes. Specific gut microbiota taxa associated with IS prognosis were identified, which may be helpful to clarify the pathogenesis of ischemic stroke and making treatment strategies.

Machine learning identifies novel coagulation genes as diagnostic and immunological biomarkers in ischemic stroke.

Coagulation system is currently known associated with the development of ischemic stroke (IS). Thus, the current study is designed to identify diagnostic value of coagulation genes (CGs) in IS and to explore their role in the immune microenvironment of IS. Aberrant expressed CGs in IS were input into unsupervised consensus clustering to classify IS subtypes. Meanwhile, key CGs involved in IS were further selected by weighted gene co-expression network analysis (WGCNA) and machine learning methods, including random forest (RF), support vector machine (SVM), generalized linear model (GLM) and extreme-gradient boosting (XGB). The diagnostic performance of key CGs were evaluated by receiver operating characteristic (ROC) curves. At last, quantitative PCR (qPCR) was performed to validate the expressions of key CGs in IS. IS patients were classified into two subtypes with different immune microenvironments by aberrant expressed CGs. Further WGCNA, machine learning methods and ROC curves identified ACTN1, F5, TLN1, JMJD1C and WAS as potential diagnostic biomarkers of IS. In addition, their expressions were significantly correlated with macrophages, neutrophils and/or T cells. GSEA also revealed that those biomarkers may regulate IS via immune and inflammation. Moreover, qPCR verified the expressions of ACTN1, F5 and JMJD1C in IS. The current study identified ACTN1, F5 and JMJD1C as novel coagulation-related biomarkers associated with IS immune microenvironment, which enriches our knowledge of coagulation-mediated pathogenesis of IS and sheds light on next-step in vivo and in vitro experiments to elucidate the relevant molecular mechanisms.

Lifibrate attenuates blood-brain barrier damage following ischemic stroke via the MLCK/p-MLC/ZO-1 axis.

Dysfunction of tight junction proteins-associated damage to the blood-brain barrier (BBB) plays an important role in the pathogenesis of ischemic stroke. Lifibrate, an inhibitor of cholinephosphotransferase (CPT), has been used as an agent for serum lipid lowering. However, the protective effects of Lifibrate in ischemic stroke and the underlying mechanism have not been clearly elucidated. Here, we employed an in vivo mice model of MCAO and an OGD/R model in vitro. In the mice models, neurological deficit scores and infarct volume were assessed. Evans Blue solution was used to detect the BBB permeability. The TEER was examined to determine brain endothelial monolayer permeability. Here, we found that Lifibrate improved neurological dysfunction in stroke. Additionally, increased BBB permeability during stroke was significantly ameliorated by Lifibrate. Correspondingly, the reduced expression of the tight junction protein ZO-1 was restored by Lifibrate at both the mRNA and protein levels. Using an in vitro model, we found that Lifibrate ameliorated OGD/R-induced injury in human bEnd.3 brain microvascular endothelial cells by increasing cell viability but reducing the release of LDH. Importantly, Lifibrate suppressed the increase in endothelial monolayer permeability and the reduction in TEER induced by OGD/R via the rescue of ZO-1 expression. Mechanistically, Lifibrate blocked activation of the MLCK/ p-MLC signaling pathway in OGD/R-stimulated bEnd.3 cells. In contrast, overexpression of MLCK abolished the protective effects of Lifibrate in endothelial monolayer permeability, TEER, as well as the expression of ZO-1. Our results provide a basis for further investigation into the neuroprotective mechanism of Lifibrate during stroke.

Role of autophagy in ischemic stroke: insights from animal models and preliminary evidence in the human disease.

Stroke represents a main cause of death and permanent disability worldwide. The molecular mechanisms underlying cerebral injury in response to the ischemic insults are not completely understood. In this article, we summarize recent evidence regarding the role of autophagy in the pathogenesis of ischemic stroke by reviewing data obtained in murine models of either transient or permanent middle cerebral artery occlusion, and in the stroke-prone spontaneously hypertensive rat. Few preliminary observational studies investigating the role of autophagy in subjects at high cerebrovascular risk and in cohorts of stroke patients were also reviewed. Autophagy plays a dual role in neuronal and vascular cells by exerting both protective and detrimental effects depending on its level, duration of stress and type of cells involved. Protective autophagy exerts adaptive mechanisms which reduce neuronal loss and promote survival. On the other hand, excessive activation of autophagy leads to neuronal cell death and increases brain injury. In conclusion, the evidence reviewed suggests that a proper manipulation of autophagy may represent an interesting strategy to either prevent or reduce brain ischemic injury.

The LPS-inactivating enzyme acyloxyacyl hydrolase protects the brain from experimental stroke

Blood-brain-barrier (BBB) disruption is a pathological hallmark of ischemic stroke, and inflammation occurring at the BBB contributes to the pathogenesis of ischemic brain injury. Lipopolysaccharide (LPS), a cell wall component of Gram-negative bacteria, is elevated in patients with acute stroke. The activity of LPS is controlled by acyloxyacyl hydrolase (AOAH), a host enzyme that deacylates LPS to inactivated forms. However, whether AOAH influences the pathogenesis of ischemic stroke remain elusive. We performed in vivo experiments to explore the role and mechanism of AOAH on neutrophil extravasation, BBB disruption, and brain infarction. We found that AOAH was upregulated in neutrophils in peri-infarct areas from mice with transient focal cerebral ischemia. AOAH deficiency increased neutrophil extravasation into the brain parenchyma and proinflammatory cytokine production, broke down the BBB and worsened stroke outcomes in mice. These effects require Toll-like receptor 4 (TLR4) because absence of TLR4 or pharmacologic inhibition of TLR4 signaling prevented the exacerbated inflammation and BBB damage in Aoah−/− mice after ischemic stroke. Importantly, neutrophil depletion or inhibition of neutrophil trafficking by blocking LFA-1 integrin dramatically reduced stroke-induced BBB breakdown in Aoah−/− mice. Furthermore, virus-mediated overexpression of AOAH induced a substantial decrease in neutrophil recruitment that was accompanied by reducing BBB damage and stroke volumes. Our findings show the importance of AOAH in regulating neutrophil-dependent BBB breakdown and cerebral infarction. Consequently, strategies that modulate AOAH may be a new therapeutic approach for treatment of ischemic stroke.

The dual role of microglia in ischemic stroke and its modulation via extracellular vesicles and stem cells

AbstractStem cell‐based therapies and extracellular vesicle (EV) treatment have demonstrated significant potential for neuroprotection against ischemic stroke. Although the neuroprotective mechanisms are not yet fully understood, targeting microglia is central to promoting neuroprotection. Microglia are the resident immune cells of the central nervous system. These cells are crucial in the pathogenesis of ischemic stroke. They respond rapidly to the site of injury by releasing pro‐inflammatory cytokines, phagocytizing dead cells and debris, and recruiting peripheral immune cells to the ischemic area. Although these responses are essential for clearing damage and initiating tissue repair, excessive or prolonged microglial activation can exacerbate brain injury, leading to secondary neuroinflammation and neurodegeneration. Moreover, microglia exhibit a dynamic range of activation states with the so‐called M1 pro‐inflammatory and M2 anti‐inflammatory phenotypes, representing the two ends of the spectrum. The delivery of both EVs and stem cells modulates microglial activation, suppressing pro‐inflammatory genes, influencing the expression of transcription factors, and altering receptor expression, ultimately contributing to neuroprotection. These findings underscore the importance of understanding the complex and dynamic role of microglia in the development of effective neuroprotective strategies to reduce the effects of ischemic stroke. In this review, we examine the current state of knowledge regarding the role of microglia in ischemic stroke, including their molecular and cellular mechanisms, activation states, and interactions with other cells. We also discuss the multifaceted contributions of microglia to stem cell‐ and EV‐based neuroprotection during an ischemic stroke to provide a comprehensive understanding of microglial functions and their potential implications in stroke therapies.

Higher fibrinogen and neutrophil-to-lymphocyte ratio are associated with the early poor response to intravenous thrombolysis in acute ischemic stroke.

Inflammation and platelet activation play pivotal roles in acute ischemic stroke (AIS) pathogenesis. Early response to thrombolysis is a vital indicator for the long-term prognosis of AIS. However, the correlation between fibrinogen or the neutrophil-to-lymphocyte ratio (NLR) and the early response to intravenous thrombolysis in patients with AIS remains unclear. AIS patients undergoing intravenous thrombolysis were enrolled between January 2018 and May 2023. Blood cell counts were sampled before thrombolysis. A good response was defined as a National Institutes of Health Stroke Scale (NIHSS) score decreased ≥4 or complete recovery 24 h after thrombolysis treatment. A poor response was defined as any increase in the NIHSS score or a decrease in the NIHSS score <4 at the 24 h after thrombolysis treatment compared with that at admission. Logistic regression analysis was performed to explore the relationship of the fibrinogen level and NLR with a poor thrombolysis response. Receiver operating characteristic (ROC) analysis was used to assess the ability of the fibrinogen level and NLR to discriminate poor responders. Among 700 recruited patients, 268 (38.29%) were diagnosed with a good response, and 432 (61.71%) were diagnosed with a poor response to intravenous thrombolysis. A binary logistic regression model indicated that an elevated fibrinogen level (odds ratio [OR], 1.693; 95% confidence interval [CI] 1.325-2.122, P < 0.001) and NLR (OR, 1.253; 95% CI, 1.210-2.005, P = 0.001) were independent factors for a poor response. The area under the curve (AUC) values for the fibrinogen level, NLR and fibrinogen level combined with the NLR for a poor response were 0.708, 0.605, and 0.728, respectively. Our research indicates that the levels of fibrinogen and NLR at admission can be used as a prognostic factor to predict early poor response to intravenous thrombolysis.

Considering Context-Specific microRNAs in Ischemic Stroke with Three "W": Where, When, and What.

MicroRNAs are short non-coding RNA molecules that function as critical regulators of various biological processes through negative regulation of gene expression post-transcriptionally. Recent studies have indicated that microRNAs are potential biomarkers for ischemic stroke. In this review, we first illustrate the pathogenesis of ischemic stroke and demonstrate the biogenesis and transportation of microRNAs from cells. We then discuss several promising microRNA biomarkers in ischemic stroke in a context-specific manner from three dimensions: biofluids selection for microRNA extraction (Where), the timing of sample collection after ischemic stroke onset (When), and the clinical application of the differential-expressed microRNAs during stroke pathophysiology (What). We show that microRNAs have the utilities in ischemic stroke diagnosis, risk stratification, subtype classification, prognosis prediction, and treatment response monitoring. However, there are also obstacles in microRNA biomarker research, and this review will discuss the possible ways to improve microRNA biomarkers. Overall, microRNAs have the potential to assist clinical treatment, and developing microRNA panels for clinical application is worthwhile.

Cortisol as a cerebral cortex neurons apoptosis regulator in acute phase of ischemic stroke (clinical and pathological study)

In response to ischemic stroke (IS) a natural activation of the stress-realizing system occurs. The features of this activation influence the outcome of the acute period and the prognosis of recovery and can be adjusted. At the same time, the role of the stress-realizing system in the pathogenesis of IS is still unexplored.Objective: to investigate the effect of peripheral blood cortisol concentration on the regulation of apoptosis of neurons of the cerebral cortex in the acute phase of IS.Material and methods. A prospective clinical and pathological study was performed. It included 9 patients with IS in the left middle cerebral artery territory who were admitted to hospital and died in the hyperacute phase of IS and had no infectious complications, allergic reactions or oncological diseases and who did not undergo thrombolysis. The cerebral cortex was examined. Neuron-specific enolase (NSE), protein 53 (p53), caspase 3, caspase 8, Fas receptor (CD95), and Fas apoptotic inhibitory molecule 2 (FAIM2) were determined on the slices using an indirect immunoperoxidase immunohistochemical staining method. A total of 567 microscopic fields were analysed for the group of patients with IS and 63 fields for the control group (three people). Before death, the blood concentrations of sFas, sFasL, cortisol, adrenocorticotropic hormone, adrenaline and norepinephrine were determined by enzyme immunoassay (the control group consisted of 28 people).Results. Significant correlation was found between the proportion of casp3-positive neurons and the concentration of cortisol in peripheral blood in zones 2 (r=0.263; p&lt;0.01) and 3 (r=0.383; p&lt;0.01). In the 2nd zone, significant negative correlation was found with the concentrations of sFas (r=-0.177; p&lt;0.05) and sFasL (r=-0.164; p&lt;0.05); in the 3rd zone, significant positive correlation was found with the ratio of the concentrations of sFasL and sFas (r=0.240; p&lt;0.01). The proportion of Fas-positive neurons in the cerebral cortex correlated significantly with the concentration of the soluble form of this molecule (for the 1st zone – r=0.222, for the 2nd zone – r=0.438, for the 3rd zone – r=0.289; p&lt;0.01) and the ratio of the concentrations of sFasL and sFas (respectively: r=0.231, r=0.266 and r=0.281; p&lt;0.01) in the peripheral blood.Conclusion. Peripheral blood cortisol concentration is a factor that determines the regulation of apoptosis of neurons in the cerebral cortex in the acute phase of IS.

Cancer screening in hospitalized ischemic stroke patients: a multicenter study focused on multiparametric analysis to improve management of occult cancers.

The reciprocal promotion of cancer and stroke occurs due to changes in shared risk factors, such as metabolic pathways and molecular targets, creating a "vicious cycle." Cancer plays a direct or indirect role in the pathogenesis of ischemic stroke (IS), along with the reactive medical approach used in the treatment and clinical management of IS patients, resulting in clinical challenges associated with occult cancer in these patients. The lack of reliable and simple tools hinders the effectiveness of the predictive, preventive, and personalized medicine (PPPM/3PM) approach. Therefore, we conducted a multicenter study that focused on multiparametric analysis to facilitate early diagnosis of occult cancer and personalized treatment for stroke associated with cancer. Admission routine clinical examination indicators of IS patients were retrospectively collated from the electronic medical records. The training dataset comprised 136 IS patients with concurrent cancer, matched at a 1:1 ratio with a control group. The risk of occult cancer in IS patients was assessed through logistic regression and five alternative machine-learning models. Subsequently, select the model with the highest predictive efficacy to create a nomogram, which is a quantitative tool for predicting diagnosis in clinical practice. Internal validation employed a ten-fold cross-validation, while external validation involved 239 IS patients from six centers. Validation encompassed receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and comparison with models from prior research. The ultimate prediction model was based on logistic regression and incorporated the following variables: regions of ischemic lesions, multiple vascular territories, hypertension, D-dimer, fibrinogen(FIB), and hemoglobin(Hb). The area under the ROC curve (AUC) for the nomogram was 0.871 in the training dataset and 0.834 in the external test dataset. Both calibration curves and DCA underscored the nomogram's strong performance. The nomogram enables early occult cancer diagnosis in hospitalized IS patients and helps to accurately identify the cause of IS, while the promotion of IS stratification makes personalized treatment feasible. The online nomogram based on routine clinical examination indicators of IS patients offered a cost-effective platform for secondary care in the framework of PPPM. The online version contains supplementary material available at 10.1007/s13167-024-00354-8.

Investigation of the Effectiveness of Doxycycline on the Improvement of Oxidative Stress Biomarkers in Patients with Ischemic Stroke

Background and Objective: Considering the role of oxidative stress in the pathogenesis of ischemic stroke, antioxidant and anti-inflammatory drugs can be a potential treatment in these patients. This study aimed to investigate the effectiveness of doxycycline on the improvement of oxidative stress biomarkers in patients with ischemic stroke. Materials and Methods: This clinical trial study was performed on 48 patients with ischemic stroke who had referred to Besat Hospital in Hamadan, Iran, in 2023. They were randomly and equally assigned to the intervention (doxycycline at the rate of 100 mg every 12 hours) and placebo groups for one week. Before and after the intervention, serum levels of malondialdehyde (MDA), glutathione (GSH), total oxidant status, total antioxidant capacity, c-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were measured. Results: The study groups had no statistically significant difference in all measured biomarkers in the first 24 h after the stroke (P&gt;0.05). In both study groups, the biomarkers of MDA and total oxidant status decreased after treatment. This decrease was greater in the intervention group, compared to the placebo group with a statistically significant difference. The total antioxidant capacity and GSH increased in both groups, and this increase was more significant in the intervention group, compared to the placebo group. In both groups, serum levels of CRP and ESR decreased, but no statistically significant difference was observed between the two groups. Conclusion: Addition of doxycycline to the standard treatment of ischemic stroke patients may reduce oxidative stress biomarkers; however, to confirm the results of this study, studies with a larger sample size are needed.

Deciphering neuroprotective mechanism of nitroxoline in cerebral ischemia: network pharmacology and molecular modeling-based investigations.

Cerebral ischemia is one of the major causes of death and disability worldwide. Currently, existing approved therapies are based on reperfusion and there is an unmet need to search for drugs with neuroprotective effects. The present study aims to investigate the neuroprotective mechanisms of nitroxoline, a nitro derivative of 8-Hydroxyquinoline, against cerebral ischemia using integrated network pharmacology and molecular docking approaches. Critical analytical tools used were SwissTarget, PharmMapper, BindingDB, DisGeNet, Cytoscape, GeneMANIA, ShinyGo, Metascape, GeneCodis, and Schrodinger GLIDE. Thirty-six overlapping drug and disease targets were identified and used for further analysis. Gene Ontology results showed that nitroxoline enriched the genes involved in biological processes of oxidative stress and apoptotic cell death that are highly implicated in hypoxic injury. KEGG enrichment analysis showed nitroxoline influenced a total of 159 biological pathways, out of which, top pathways involved in cerebral ischemia included longevity regulating pathway, VEGF signaling, EGFR tyrosine kinase inhibitor resistance, IL-17 and HIF-1 pathways, FoxO signaling, and AGE-RAGE pathway. Protein-protein interaction analysis using string database showed PARP1, EGFR, PTEN, BRD4, RAC1, NOS2, MTOR, MAPK3, BCL2, MAPK1, APP, METAP2, MAPK14, SIRT1, PRKAA1, and MCL1 as highly interactive proteins involved in pathogenesis of ischemic stroke regulated by nitroxoline. The highly interactive protein targets were validated by molecular docking studies and molecular dynamic simulations. Amongst all these targets, nitroxoline showed the highest binding affinity towards BRD4 followed by PARP1 and PTEN.Nitroxoline, through network pharmacology analysis, showed a role in regulating proteins, biological processes, and pathways crucial in cerebral ischemia. The current study thus provides a preliminary insight that nitroxoline might be used as a neuroprotectant against cerebral ischemia via modulating the epigenetic reader BRD4 and transcription factors such as RELA, NF-κβ1, and SP1. However, further in-vitro and preclinical studies need to be performed for concrete evidence.

CircSKA3 is Associated With the Risk of Extracranial Artery Stenosis and Plaque Instability Among Ischemic Stroke Patients.

Circular RNA circSKA3 (spindle and kinetochore-related complex subunit 3) has been identified as a prognostic factor in ischemic stroke. The objective of this study was to investigate the association of circSKA3 with the risk of extracranial artery stenosis (ECAS) and plaque instability in patients with ischemic stroke. We constructed a competing endogenous RNA (ceRNA) network regulated by circSKA3 based on differentially expressed circRNAs and mRNAs between five patients and five controls. Gene Ontology (GO) analysis was performed on the 65 mRNAs within the network, revealing their primary involvement in inflammatory biological processes. A total of 284 ischemic stroke patients who underwent various imaging examinations were included for further analyses. Each 1 standard deviation increase in the log-transformed blood circSKA3 level was associated with a 56.3% increased risk of ECAS (P = 0.005) and a 142.1% increased risk of plaque instability (P = 0.005). Patients in the top tertile of circSKA3 had a 2.418-fold (P < 0.05) risk of ECAS compared to the reference group (P for trend = 0.02). CircSKA3 demonstrated a significant but limited ability to discriminate the presence of ECAS (AUC = 0.594, P = 0.015) and unstable carotid plaques (AUC = 0.647, P = 0.034). CircSKA3 improved the reclassification power for ECAS (NRI: 9.86%, P = 0.012; IDI: 2.97%, P = 0.007) and plaque instability (NRI: 36.73%, P = 0.008; IDI: 7.05%, P = 0.04) beyond conventional risk factors. CircSKA3 played an important role in the pathogenesis of ischemic stroke by influencing inflammatory biological processes. Increased circSKA3 was positively associated with the risk of ECAS and plaque instability among ischemic stroke patients.

The Untargeted Metabolomics Reveals Differences in Energy Metabolism in Patients with Different Subtypes of Ischemic Stroke.

Ischemic stroke (IS) is the most common subtype of stroke. The risk factors and pathogenesis of IS are complex and varied due to different subtypes. Therefore, we used metabolomics technology to investigate the biomarkers and potential pathophysiological mechanisms of different subtypes of IS. We included 126 IS patients and divided them into two groups based on the TOAST classification: large-artery atherosclerosis (LAA) group (n = 87) and small-vessel occlusion (SVO) group (n = 39). Plasma metabolomics analysis was performed using liquid chromatography-high-resolution mass spectrometry (LC-HRMS) to identify metabolic profiles in LAA and SVO subtype IS patients and to determine metabolic differences between patients with the two subtypes of IS. We identified 26 differential metabolites between LAA and SVO subtype IS. A multiple prediction model based on the plasm metabolites had good predictive ability for IS subtyping (AUC = 0.822, accuracy = 77.8%), with 12,13-DHOME being the most important differential metabolite in the model. The differential metabolic pathways between the two subtypes of IS patients included tricarboxylic acid (TCA) cycle, alanine, aspartate and glutamate metabolism, and pyruvate metabolism, mainly focused on energy metabolism. 12,13-DHOME emerged as the primary discriminatory metabolite between LAA and SVO subtypes of IS. In LAA subtype IS patients, energy metabolism, encompassing pyruvate metabolism and the TCA cycle, exhibited lower activity levels when compared to patients with the SVO subtype IS. The utilization of targeted metabolomics holds the potential to improve diagnostic accuracy for distinguishing stroke subtypes.

Indicators of cognitive impairment of varying severity in the acute period of ischemic stroke

To assess phenotype and identify biomarkers of cognitive impairment (CI) of varying severity in patients in the acute period of ischemic stroke (IS) based on the analysis of clinical and paraclinical indicators. Two hundred and forty patients with diagnosed IS and presence of CI were examined. Depending on the scores on the Montreal Cognitive Assessment Scale, patients were divided into two groups: group 1 (n=182) with mild CI, group 2 (n=58) with dementia. On admission, stroke severity according to the National Institutes of Health Stroke Scale (NIHSS), activities of daily living assessed by the Barthel Scale and patient independence assessed by the modified Rankin Scale (mRS) were determined. Neuropsychological examination was performed on day 14 and included investigation of episodic memory, executive functions, speech, gnosis, praxis, and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) parameters. Immunological diagnostics included a study of the concentration of cytokines of various groups (interleukin (IL)-1b, IL-6, IL-16, granulocyte-macrophage colony-stimulating factor (GM-CSF), chemokines CXCL10, CXCL11, CXCL9, tumor necrosis factor α (TNFα)). Neuroimaging parameters were assessed using brain MRI data with verification of the STRIVE criteria and the medial temporal lobe atrophy scale (MTA). The standard application software package SPSS Statistics, Pandas and SciPy libraries were used for statistical analysis. Patients of group 2 had lower scores in all cognitive domains with the greatest reduction in perception, constructive praxis, semantic information processing and mnestic function. These analyses revealed a higher degree of IQCODE, prevalence of features corresponding to STRIVE/MTA criteria in patients of group 2, while patients of group 1 had higher NIHSS and mRS scores. When serum concentrations of cytokines were assessed, patients of group 1 showed higher concentrations of IL-1b, IL-6, GM-CSF and TNFα, while group 2 patients had higher concentrations of cytokine CXCL10. The presence of pre-stroke CI, baseline indicators of the patient's functional status, neuroimaging parameters of MTA/STRIVE and age are reflected in the structure and severity of cognitive deficit in the acute period of IS. Investigation of the role of interleukins, GM-CSF, TNFα and CXCL10 in the pathogenesis of IS and their association with the progression of post-stroke CI requires further studies with a larger sample size and longer follow-up period.

Hospital-Level Variability in Reporting of Ischemic Stroke Subtypes and Supporting Diagnostic Evaluation in GWTG-Stroke Registry.

Secondary prevention of ischemic stroke (IS) requires adequate diagnostic evaluation to identify the likely etiologic subtype. We describe hospital-level variability in diagnostic testing and IS subtyping in a large nationwide registry. We used the GWTG-Stroke (Get With The Guidelines-Stroke) registry to identify patients hospitalized with a diagnosis of acute IS at 1906 hospitals between January 1, 2016, and September 30, 2017. We compared the documentation rates and presence of risk factors, diagnostic testing, achievement/quality measures, and outcomes between patients with and without reported IS subtype. Recording of diagnostic evaluation was optional in all IS subtypes except cryptogenic, where it was required. Of 607 563 patients with IS, etiologic IS subtype was documented in 57.4% and missing in 42.6%. Both the rate of missing stroke pathogenesis and the proportion of cryptogenic strokes were highly variable across hospitals. Patients missing stroke pathogenesis less frequently had documentation of risk factors, evidence-based interventions, or discharge to home. The reported rates of major diagnostic testing, including echocardiography, carotid and intracranial vascular imaging, and short-term cardiac monitoring were <50% in patients with documented IS pathogenesis, although these variables were missing in >40% of patients. Long-term cardiac rhythm monitoring was rarely reported, even in cryptogenic stroke. Reporting of IS etiologic subtype and supporting diagnostic testing was low overall, with high rates of missing optional data. Improvement in the capture of these data elements is needed to identify opportunities for quality improvement in the diagnostic evaluation and secondary prevention of stroke.