Fibrinolysis: strategies to enhance the treatment of acute ischemic stroke

Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway

JOURNAL/nrgr/04.03/01300535-202511000-00028/figure1/v/2024-12-20T164640Z/r/image-tiff Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells, and can thus be used as substitutes for stem cells in stem cell therapy, thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived treatments. This lays a foundation for the development of potentially potent new treatment modalities for ischemic stroke. However, the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear, presenting challenges for clinical translation. To promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside, we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic stroke. We found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal apoptosis. The human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase, mammalian target of rapamycin, and protein kinase B, and these effects were reversed by treatment with a phosphoinositide 3-kinase inhibitor. These findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway. Finally, we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety profile. Therefore, human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke.

Development of an assay to quantify tranexamic acid levels in plasma

Dysregulations of blood clot breakdown (fibrinolysis) during vascular trauma can lead to excessive blood loss. Tranexamic acid (TXA) is an inhibitor of fibrinolysis that works by blocking the interaction between plasminogen and fibrin degradation products (FDPs) - a key step in fibrinolysis. Despite the widespread usage, there are no tests available in a clinical setting to monitor TXA levels. We developed a fluorescence resonance energy transfer (FRET)-based assay to quantify TXA concentrations in plasma by using 1) fluorescently labeled plasminogen, and 2) FDPs labeled with a fluorescence quencher. Once plasminogen binds the FDPs, the fluorescent signal is quenched. TXA causes plasminogen to dissociate from the FDPs, thus increasing fluorescence signal in a dose-dependent manner. The dose response was sensitive between 1 and 100 μM (0.16 and 15.7 mg/L). The intraassay and interassay variabilities were determined to be 5.7 % and 3.0 %, respectively. Limit of detection was estimated to be 0.28 μM (0.044 mg/L). When tested for measuring known levels of TXA added to plasma samples, the ratio between measured and expected TXA concentration was 1.0151. Our study demonstrates a novel assay that can rapidly quantify TXA concentrations in plasma samples, thus demonstrating its potential as an in-hospital tool.

LncRNA SERPINB9P1 Mitigates Cerebral Injury Induced by Oxygen‒Glucose Deprivation/Reoxygenation by Interacting with HSPA2

Dysregulation of long non-coding RNAs (lncRNAs) is implicated in the pathophysiology of ischemic stroke (IS). However, the molecular mechanism of the lncRNA SERPINB9P1 in IS remains unclear. Our study aimed to explore the role and molecular mechanism of the lncRNA SERPINB9P1 in IS. This study revealed downregulation of the lncRNA SERPINB9P1 in the peripheral blood of IS patients, which was corroborated by the GSE140275 dataset. Furthermore, high lncRNA SERPINB9P1 expression was associated with lower National Institutes of Health Stroke Scale (NIHSS) scores and favorable outcome. Clinically, lncRNA SERPINB9P1 expression was correlated with inflammation and coagulation parameters in IS patients. Furthermore, lncRNA SERPINB9P1 silencing inhibited cell viability, induced apoptosis and inflammatory response under oxygen-glucose deprivation/reperfusion ; however, these effects were reversed upon its overexpression. Additionally, Chromatin Isolation by RNA Purification and mass spectrometry (CHIRP-MS) and western blot confirmed that the lncRNA SERPINB9P1 was involved in the pathological process of IS through binding to heat shock protein 2 (HSPA2). HSPA2 was upregulated in IS patients, and its protein interaction network was significantly enriched in IS-related pathways. In conclusion, the lncRNA SERPINB9P1 may ameliorate neurological injury in IS patients by interacting with the HSPA2 protein and engaging in IS-related pathways, providing new insights into treatment strategies for IS.

Thrombus composition and its implication in ischemic stroke assessment and revascularization treatments

INTRODUCTION

Since mechanical thrombectomy has allowed ischaemic stroke thrombus retrieval, the exhaustive study of this material has enabled better understanding of the potential physiopathological processes involved in thrombus formation.

DEVELOPMENT

Thrombotic pathways involved in the different vascular beds share common mechanisms, causing difficulties in the identification of specific patterns associated with stroke aetiology. However, other factors such as clot formation time, associated inflammatory status, or activation of additional immune and coagulation pathways (neutrophil extracellular trap [NET] delivery, platelet aggregation, endothelial activation, and von Willebrand Factor release) have been described as determinants in thrombus characteristics. Thus, variable proportions of fibrin-/platelet-rich and erythrocyte-rich areas are closely interrelated within the thrombus, frequently associated with a protective outer shell with high concentrations of fibrin, NETs, and von Willebrand Factor. The presence of these components, as well as their distribution and interrelationships, have been shown to have effects on the thrombus' resistance to revascularisation treatments. Understanding of these pathways has enabled the development of adjuvant therapies capable of enhancing current fibrinolytic drugs and/or increasing the efficacy of endovascular treatments.

CONCLUSION

Understanding of thrombus components and mechanisms involved in thrombus formation represent a potential pathway for the development of ischaemic stroke therapeutics with promising perspectives.

Guhong injection attenuates brain injury and promotes neuroprotection after acute ischemic stroke

BACKGROUND AND OBJECTIVES

Guhong injection (GHI) has multiple components and generates diverse effects, and is mainly used in the treatment of acute ischemic stroke (AIS). The purpose of this study is to explore the multiple effects of GHI in AIS models in mice and the mechanism how they work together to affect the stroke outcome.

METHODS

Middle cerebral artery occlusion (MCAO) and photothrombotic stroke models were established with GHI or vehicle. Neurological function assessment including the Modified Neurological Severity Score (mNSS) and rota-rod test, and relative cerebral blood flow were monitored at day 1 and day 3 after model establishment. Flow cytometry, 2, 3, 5-Triphenyltetrazolium chloride (TTC) staining, histology and immunofluorescence, Western blotting (WB) assay were performed at day 3.

RESULTS

The mean mNSS score was lower and the latency to falling off the rota-rod was prolonged at day 3 in the GHI group. GHI reduced the relative infarct volume and increased the relative cerebral blood flow. The histopathological damage of ischemic core was significantly ameliorated in the GHI group. GHI decreased the Caspase-3+ cells and increased the MAP-2+ and Claudin-5+ cells. GHI increased the expression of Bcl-2 and the ratio of Bcl-2/Bax, and decreased the expression levels of Bax, Caspase-3 and Cleaved-Caspased-3. GHI reduced the microglia, decreased the IL-6 positive cells, TNF-α positive cells and increased TGF-β1 positive cells.

CONCLUSIONS

GHI alleviated brain injury and neurological deficits through improving cerebral blood circulation, attenuating neuronal apoptosis, reducing the disruption of blood-brain barrier (BBB) and decreasing neuroinflammation in MCAO and photothrombotic stroke models in mice. GHI has certain neuroprotective function to be applied to clinical use.

The Joint Effect of Renal Function Status and Coagulation Biomarkers on In-Hospital Outcomes in Acute Ischemic Stroke Patients With Intravenous Thrombolysis

OBJECTIVE

To demonstrate whether combining renal function status [estimating glomerular filtration rate (eGFR)] with coagulation biomarkers [fibrinogen (Fg) and d-dimer] is more beneficial in predicting in-hospital outcomes following intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients.

METHODS

We studied 417 AIS patients with IVT. According to the cut-offs of coagulation biomarkers (Fg and d-dimer) and eGFR determined by receiver operating characteristic (ROC) curves, the patients were divided into four groups: LFLG (low Fg and low eGFR), LFHG (low Fg and high eGFR), HFLG (high Fg and low eGFR), and HFHG (high Fg and high eGFR); or LDLG (low d-dimer and low eGFR), LDHG (low d-dimer and high eGFR), HDLG (high d-dimer and low eGFR), and HDHG (high d-dimer and high eGFR). Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for poor outcomes at discharge and post-stroke pneumonia across the four groups.

RESULTS

The patients in the HFLG and HDLG groups had the poorest prognosis at discharge and the highest risk of in-hospital pneumonia. They experienced 3.00 or 4.59 times higher risk of in-hospital pneumonia than those in the LFHG and LDHG groups (95%CI: 1.07-8.44, p < 0.05; 95%CI: 1.58-13.32, p = 0.005). Similarly, the risk of adverse outcome at discharge was 3.02 and 1.52 times higher in HFLG and HDLG groups (95%CI: 1.63-9.91, p < 0.005; 95%CI: 1.11-5.74, p < 0.05) compared to that in LFHG and LDHG groups. Adding eGFR and Fg or d-dimer to the risk model improved the risk reclassification for in-hospital pneumonia and functional outcomes at discharge.

CONCLUSION

Combining renal function status and coagulation biomarkers within 4.5 h after onset could better predict in-hospital outcomes of AIS patients with IVT.

The therapeutic effects of salvianolic acids on ischemic stroke: From molecular mechanisms to clinical applications

Ischemic stroke (IS), primarily caused by cerebrovascular occlusion, poses a significant public health challenge with limited effective therapeutic options. Evidence suggests that salvianolic acids (SAs), mainly from Salvia miltiorrhiza Bunge, have been formulated into injections and are widely used in clinical treatments for cardiovascular and cerebrovascular diseases, including stroke. The pharmacological properties of SAs include reducing neuroinflammation, alleviating oxidative stress injury, inhibiting cellular apoptosis, preserving endothelial function, maintaining blood-brain barrier integrity, and promoting angiogenesis. Salvianolic acids for injection (SAFI) serve as a safe and effective treatment option for cardiovascular and cerebrovascular conditions by influencing various signaling pathways and molecular targets associated with these diseases. In this review, we first discuss the pathogenesis of IS, then summarize the classification of SAs, elaborate detailed molecular mechanisms of their efficacy, and the related clinical applications of SAFI. We also emphasize the recent pharmacological advancements and therapeutic possibilities of this promising drug preparation derived from herbs for cerebrovascular conditions.

Sbno1 mediates cell-cell communication between neural stem cells and microglia through small extracellular vesicles

BACKGROUND

Neural stem cells (NSCs) play a crucial role in the progress of ischemic stroke. Research on zebrafish embryonic demonstrates an association between Strawberry Notch 1 (Sbno1) and central nervous system development. However, the regulation and underlying mechanism of Sbno1 in NSCs have not been studied yet. Here, we investigated the role and the mechanism of Sbno1 in NSCs development and the potential therapeutic value of Sbno1 in ischemic stroke.

METHODS

Adeno-associated virus (AAV) was used for overexpression or knockdown of Sbno1 in vitro or in vivo. A mouse model of MCAO was established to evaluate the neuroprotective effects of AAV-Sbno1, including balance beam test, rotarod test, and strength evaluation. H&E and immunofluorescence assessed neuronal impairment. Western blot and RT-qPCR were used to detect the expression of Sbno1 and its downstream target genes. RNA-seq and western blot were performed to explore further molecular mechanisms by which Sbno1 promoted endogenous repair of NSCs and macrophages M2 polarization. CCK8 was conducted to assess the effects of Sbno1 on NSCs proliferation. The impact of Sbno1 on NSCs apoptosis was evaluated by flow cytometry. NSCs derived from small extracellular vesicles (sEV) were obtained using ultracentrifugation and identified through nanoparticle tracking analysis (NTA) and western blot analysis.

RESULTS

Our results showed that Sbno1 is highly expressed in the central nervous system, which plays a crucial role in regulating the proliferation of NSCs through the PI3k-Akt-GSK3β-Wnt/β-catenin signaling pathway. In addition, with overexpression of Sbno1 in the hippocampus, post-stroke behavioral scores were superior to the wild-type mice, and immunofluorescence staining revealed an increased number of newly generated neurons. sEV released by NSCs overexpressing Sbno1 inhibited neuroinflammation, which mechanistically impaired the activation of the microglial NF-κB and MAPK signaling pathways.

CONCLUSIONS

Our studies indicate that sbno1 promotes the proliferation of NSCs and enhances endogenous repairing through the PI3k-Akt-GSK3β-Wnt/β-catenin signaling pathway. Additionally, NSCs overexpressing sbno1 improve ischemic stroke recovery and inhibit neuroinflammation after ischemia by sEV through the MAPK and NF-κB signaling pathways.

Combining systems pharmacology, metabolomics, and transcriptomics to reveal the mechanism of Salvia miltiorrhiza-Cortex moutan herb pair for the treatment of ischemic stroke

Ischemic stroke (IS), predominantly triggered by blockages in cerebral blood flow, is increasingly recognized as a critical public health issue. The combination of Salvia miltiorrhiza (SM) and Cortex moutan (CM), traditional herbs in Eastern medicine, are frequently used for managing heart and brain vascular conditions. However, the exact mechanisms by which this herb pair (SC) combats IS remain largely unexplored. This investigation focuses on pinpointing the active constituents in SC that contribute to its protective role and deciphering the mechanisms countering cerebral ischemia, particularly in a middle cerebral artery occlusion (MCAO) rat model. We employed UPLC-Q-TOF-MS/MS alongside network pharmacology for predicting SC's target actions against IS. Key ingredients were examined for their interaction with principal targets using molecular docking. The therapeutic impact was gauged through H&E, TUNEL, and Nissl staining, complemented by transcriptomic and metabolomic integration for mechanistic insights, with vital genes confirmed via western blot. UPLC-Q-TOF-MS/MS analysis revealed that the main components of SC included benzoylpaeoniflorin, salvianolic acid B, oxypaeoniflora, salvianolic acid A, and others. Network pharmacology analysis indicated that SC's mechanism in treating IS primarily involves inflammation, angiogenesis, and cell apoptosis-related pathways, potentially through targets such as AKT1, TNF, PTGS2, MMP9, PIK3CA, and VEGFA. Molecular docking underscored strong affinities between these constituents and their targets. Our empirical studies indicated SC's significant role in enhancing neuroprotection in IS, with transcriptomics suggesting the involvement of the VEGFA/PI3K/AKT pathway and metabolomics revealing improvements in various metabolic processes, including amino acids, glycerophospholipids, sphingomyelin, and fatty acids metabolisms.

Safety, tolerability, and pharmacokinetic of HY0721 in Chinese healthy subjects: A first-in-human randomized, double-blind, placebo-controlled dose escalation phase I study

BACKGROUND

HY0721 is a novel inhibitor of sulfonylurea receptor 1-transient receptor potential melastatin 4 (SUR1-TRPM4) for the treatment of acute ischemic stroke. This study aimed to evaluate the safety, tolerability, and pharmacokinetic (PK) profiles of single and multiple intravenous administration of HY0721 in Chinese healthy subjects.

METHODS

The study enrolled 48 and 30 healthy volunteers in the single-ascending dose (SAD) cohort (20, 60, 120, 240, and 320 mg) and multiple-ascending dose (MAD) cohort (60, 120, and 160 mg/bid), respectively, to receive the corresponding dosage of HY0721 or placebo. Safety monitoring included but was not limited to recording adverse events (AEs), vital signs, electrocardiograms, and laboratory tests. The blood samples were collected from subjects to determine the concentrations of HY0721 for PK evaluation.

RESULTS

The administration of HY0721 showed good safety and tolerability up to 320 mg in the SAD study and up to 160 mg twice daily in the MAD study. The most common AE was injection site reaction, and no AE led to discontinuation of administration or subject dropout. The exposures of HY0721 increased greater than dose proportional manner at the dosages of 20 to 320 mg in the SAD study. A linear PK profile was observed following multiple doses ranging from 60 to 160 mg twice daily, with no evidence of accumulation. Additionally, the human effective dose of HY0721 was estimated to be 120 mg.

CONCLUSION

This study demonstrated the intravenous administration of HY0721 is safe and well-tolerated in Chinese healthy subjects and provided 60 to 160 mg b.i.d. as the recommended dosing range for further clinical trials.

TRIAL REGISTRATION

ChinaDrugTrials.Org.cn; No. CTR20202604, 18 December 2020.

Effect of comprehensive nursing on swallowing function and quality of life in patients with ischemic stroke

Hu et al explored the impact of comprehensive nursing model on swallowing function and quality of life in patients with ischemic stroke. They divided 172 patients into the control group (routine care) and the research group (comprehensive care), and used standard scales to evaluate the swallowing function, neurological deficit, anxiety and depression, daily living ability, and exercise of the two groups of patients before and after care. Changes in indicators of function, quality of life, and compliance. The results showed that compared with the control group, patients in the study group achieved significant improvements in various indicators, with a lower incidence of adverse reactions and higher satisfaction with care. These data suggest that the comprehensive nursing model can significantly improve the swallowing function, quality of life and satisfaction of patients with ischemic stroke. In the future, the development of comprehensive nursing models needs to focus on technological innovation, humanized services, continuing education and training, multi-disciplinary collaboration, optimal allocation of resources, standardized practice and evaluation, etc., in order to improve nursing effects and promote the improvement of medical service quality.

Neutrophil migration participates in the side effect of recombinant human tissue plasminogen activator

AIMS

Ischemic stroke remains a challenge in medical research because of the limited treatment options. Recombinant human tissue plasminogen activator (rtPA) is the primary treatment for recanalization. However, nearly 50% of the patients experience complications that result in ineffective reperfusion. The precise factors contributing to ineffective reperfusion remain unclear; however, recent studies have suggested that immune cells, notably neutrophils, may influence the outcome of rtPA thrombolysis via mechanisms such as the formation of neutrophil extracellular traps. This study aimed to explore the nonthrombolytic effects of rtPA on neutrophils and highlight their contribution to ineffective reperfusion.

METHODS

We evaluated the effects of rtPA treatment on middle cerebral artery occlusion in rats. We also assessed neutrophil infiltration and activation after rtPA treatment in vitro and in vivo in a small cohort of patients with massive cerebral ischemia (MCI).

RESULTS

rtPA increased neutrophil infiltration into the brain microvessels and worsened blood-brain barrier damage during ischemia. It also increased the neutrophil counts of the patients with MCI.

CONCLUSION

Neutrophils play a crucial role in promoting ischemic injury and blood-brain barrier disruption, making them potential therapeutic targets.

tPA supplementation preserves neurovascular and cognitive function in Tg2576 mice

INTRODUCTION

Amyloid beta (Aβ) impairs the cerebral blood flow (CBF) increase induced by neural activity (functional hyperemia). Tissue plasminogen activator (tPA) is required for functional hyperemia, and in mouse models of Aβ accumulation tPA deficiency contributes to neurovascular and cognitive impairment. However, it remains unknown if tPA supplementation can rescue Aβ-induced neurovascular and cognitive dysfunction.

METHODS

Tg2576 mice and wild-type littermates received intranasal tPA (0.8 mg/kg/day) or vehicle 5 days a week starting at 11 to 12 months of age and were assessed 3 months later.

RESULTS

Treatment of Tg2576 mice with tPA restored resting CBF, prevented the attenuation in functional hyperemia, and improved nesting behavior. These effects were associated with reduced cerebral atrophy and cerebral amyloid angiopathy, but not parenchymal amyloid.

DISCUSSION

These findings highlight the key role of tPA deficiency in the neurovascular and cognitive dysfunction associated with amyloid pathology, and suggest potential therapeutic strategies involving tPA reconstitution.

HIGHLIGHTS

Amyloid beta (Aβ) induces neurovascular dysfunction and impairs the increase of cerebral blood flow induced by neural activity (functional hyperemia). Tissue plasminogen activator (tPA) deficiency contributes to the neurovascular and cognitive dysfunction caused by Aβ. In mice with florid amyloid pathology intranasal administration of tPA rescues the neurovascular and cognitive dysfunction and reduces brain atrophy and cerebral amyloid angiopathy. tPA deficiency plays a crucial role in neurovascular and cognitive dysfunction induced by Aβ and tPA reconstitution may be of therapeutic value.

The role of the D-dimer to fibrinogen ratio in the classification of cardioembolism and atherosclerotic stroke

BACKGROUND

The D-dimer-to-fibrinogen ratio (DFR) is a good indicator of thrombus activity in thrombotic diseases, but its clinical role in acute ischaemic stroke (AIS) patients with different etiologies has not been studied. We evaluated the diagnostic value of the DFR for different subtypes of AIS.

METHODS

We conducted a single-center retrospective study of 269 patients with AIS who were referred to our stroke center within 4.5 h from Jan 2017 to Oct 2019. Coagulation data including DFRs were compared among the different stroke subtypes, and a separate retrospective validation sample was utilized to evaluate the prediction efficiency of the DFR for subtype diagnosis.

RESULTS

A higher DFR was observed in patients with cardioembolism than in those with large artery atherosclerosis (LAA) (odds ratio (OR) per 0.1 increase of the DFR: 1.49 [1.01-2.18]) after we adjusted for vascular risk factors. The diagnostic value of the DFR for detecting cardioembolism (AUC = 0.722, 95 % CI = 0.623-0.820) exceeded that of isolated D-dimer or fibrinogen. The validation sample (n = 117) further supported the notion that a diagnosis of cardioembolism was more common in patients with a DFR > 0.11 (multivariable risk ratio = 3.11[1.33-7.31], P = 0.009).

CONCLUSION

High DFRs were associated with cardioembolism in patients with AIS. The utilization of DFR can be beneficial for distinguishing a cardiac embolic source from atherosclerotic stroke.

Scutellarin alleviates microglia-mediated neuroinflammation and apoptosis after ischemic stroke through the PI3K/AKT/GSK3β signaling pathway

Microglia are resident immune cells in the central nervous system that are rapidly activated to mediate neuroinflammation and apoptosis, thereby aggravating brain tissue damage after ischemic stroke (IS). Although scutellarin has a specific therapeutic effect on IS, the potential target mechanism of its treatment has not been fully elucidated. In this study, we explored the potential mechanism of scutellarin in treating IS using network pharmacology. Lipopolysaccharide (LPS) was used to induce an in vitro BV-2 microglial cell model, while middle cerebral artery occlusion (MCAO) was used to induce an in vivo animal model. Our findings indicated that scutellarin promoted the recovery of cerebral blood flow in MCAO rats at 3 days, significantly different from that in the MCAO group. Western blotting and immunofluorescence revealed that scutellarin treatment of BV-2 microglial cells resulted in a significant reduction in the protein expression levels and incidence of cells immunopositive for p-NF-κB, TNF-α, IL-1β, Bax, and C-caspase-3. In contrast, the expression levels of p-PI3K, p-AKT, p-GSK3β, and Bcl-2 were further increased, significantly different from those in the LPS group. The PI3K inhibitor LY294002 had similar effects to scutellarin by inhibiting neuroinflammation and apoptosis in activated microglia. The results of the PI3K/AKT/GSK3β signaling pathway and NF-κB pathway in vivo in MCAO models induced microglia at 3 days were consistent with those obtained from in vitro cells. These findings indicate that scutellarin plays a neuroprotective role by reducing microglial neuroinflammation and apoptosis mediated by the activated PI3K/AKT/GSK3β/NF-κB signaling pathway.

Effect of comprehensive nursing on the quality of life and swallowing function in individuals diagnosed with ischemic stroke

BACKGROUND

Ischemic stroke (IS) is a widely recognized disease characterized by high prevalence, mortality, morbidity, disability, and recurrence rates. It ranks prominently in terms of mortality, constituting 60%-80% of stroke cases.

AIM

To explore the impact of comprehensive nursing care on the quality of life and swallowing function in individuals diagnosed with IS.

METHODS

This study comprised 172 patients with IS admitted to our hospital between February 2018 to March 2021. The participants were divided into two groups, namely the control group (n = 80) receiving routine care and the research group (n = 92) receiving comprehensive care. Various assessment scales, including the standard swallowing function assessment scale (SSA), National Institutes of Health Stroke scale (NIHSS), European stroke scale (ESS), self-rating anxiety scale (SAS), self-rating depression scale (SDS), Barthel index (BI), and the motor function assessment scale (MAS), were employed to evaluate the improvement in swallowing function, neurological deficits, clinical outcomes, anxiety, depression, daily living activities, and motor function before and after care. Furthermore, the study compared the occurrence of adverse reactions during the nursing period, life quality before and after the intervention, rehabilitation compliance, and nursing satisfaction between the two groups.

RESULTS

After the nursing intervention, the research group exhibited significantly improved SSA and NIHSS scores compared to the control group (P < 0.05). Moreover, both groups demonstrated significant reductions in SAS and SDS scores (P < 0.05), with the research group showing more obvious advantages (P < 0.05). Compared to the control group, the research group displayed significantly better ESS, BI, and MAS scores (P < 0.05), coupled with a lower incidence of adverse reactions (P < 0.05). Additionally, the research group demonstrated markedly higher levels of life quality, rehabilitation compliance, and nursing satisfaction compared to the control group (P < 0.05).

CONCLUSION

Comprehensive nursing effectively improved swallowing function, quality of life, and patient satisfaction, highlighting its clinical significance.

Establishment and characterization of turtle liver organoids provides a potential model to decode their unique adaptations

Painted turtles are remarkable for their freeze tolerance and supercooling ability along with their associated resilience to hypoxia/anoxia and oxidative stress, rendering them an ideal biomedical model for hypoxia-induced injuries (including strokes), tissue cooling during surgeries, and organ cryopreservation. Yet, such research is hindered by their seasonal reproduction and slow maturation. Here we developed and characterized adult stem cell-derived turtle liver organoids (3D self-assembled in vitro structures) from painted, snapping, and spiny softshell turtles spanning ~175My of evolution, with a subset cryopreserved. This development is, to the best of our knowledge, a first for this vertebrate Order, and complements the only other non-avian reptile organoids from snake venom glands. Preliminary characterization, including morphological, transcriptomic, and proteomic analyses, revealed organoids enriched in cholangiocytes. Deriving organoids from distant turtles and life stages demonstrates that our techniques are broadly applicable to chelonians, permitting the development of functional genomic tools currently lacking in herpetological research. Such platform could potentially support studies including genome-to-phenome mapping, gene function, genome architecture, and adaptive responses to climate change, with implications for ecological, evolutionary, and biomedical research.

Adenosine A2A receptor blockade attenuates excitotoxicity in rat striatal medium spiny neurons during an ischemic-like insult

During brain ischemia, excitotoxicity and peri-infarct depolarization injuries occur and cause cerebral tissue damage. Indeed, anoxic depolarization, consisting of massive neuronal depolarization due to the loss of membrane ion gradients, occurs in vivo or in vitro during an energy failure. The neuromodulator adenosine is released in huge amounts during cerebral ischemia and exerts its effects by activating specific metabotropic receptors, namely: A1, A2A, A2B, and A3. The A2A receptor subtype is highly expressed in striatal medium spiny neurons, which are particularly susceptible to ischemic damage. Evidence indicates that the A2A receptors are upregulated in the rat striatum after stroke and the selective antagonist SCH58261 protects from exaggerated glutamate release within the first 4 hours from the insult and alleviates neurological impairment and histological injury in the following 24 hours. We recently added new knowledge to the mechanisms by which the adenosine A2A receptor subtype participates in ischemia-induced neuronal death by performing patch-clamp recordings from medium spiny neurons in rat striatal brain slices exposed to oxygen and glucose deprivation. We demonstrated that the selective block of A2A receptors by SCH58261 significantly reduced ionic imbalance and delayed the anoxic depolarization in medium spiny neurons during oxygen and glucose deprivation and that the mechanism involves voltage-gated K+ channel modulation and a presynaptic inhibition of glutamate release by the A2A receptor antagonist. The present review summarizes the latest findings in the literature about the possibility of developing selective ligands of A2A receptors as advantageous therapeutic tools that may contribute to counteracting neurodegeneration after brain ischemia.

The role and therapeutic potential of nuclear factor κB (NF-κB) in ischemic stroke

Stroke is a prevalent cerebrovascular condition with a global impact, causing significant rates of illness and death. Despite extensive research, the available treatment options for stroke remain restricted. Hence, it is crucial to gain a deeper understanding of the molecular mechanisms associated with the onset and advancement of stroke in order to establish a theoretical foundation for novel preventive and therapeutic approaches. NF-κB, also known as nuclear factor κB, is a transcription factor responsible for controlling the expression of numerous genes and plays a crucial role in diverse physiological processes. NF-κB is triggered and regulates neuroinflammation and other processes after stroke, promoting the generation of cytokine storms and contributing to the advancement of ischemic stroke (IS). Therefore, NF-κB could potentially play a vital role in stroke by regulating diverse pathophysiological processes. This review provides an overview of the functions of NF-κB in stroke and its governing mechanisms. In addition, our attention is directed towards various potential therapies that aim to inhibit the NF-κB signaling pathway in order to offer valuable insights for the advancement of innovative treatment approaches for stroke.

Inhaled nitric oxide suppresses neuroinflammation in experimental ischemic stroke

Ischemic stroke is a major global health issue and characterized by acute vascular dysfunction and subsequent neuroinflammation. However, the relationship between these processes remains elusive. In the current study, we investigated whether alleviating vascular dysfunction by restoring vascular nitric oxide (NO) reduces post-stroke inflammation. Mice were subjected to experimental stroke and received inhaled NO (iNO; 50 ppm) after reperfusion. iNO normalized vascular cyclic guanosine monophosphate (cGMP) levels, reduced the elevated expression of intercellular adhesion molecule-1 (ICAM-1), and returned leukocyte adhesion to baseline levels. Reduction of vascular pathology significantly reduced the inflammatory cytokines interleukin-1β (Il-1β), interleukin-6 (Il-6), and tumor necrosis factor-α (TNF-α), within the brain parenchyma. These findings suggest that vascular dysfunction is responsible for leukocyte adhesion and that these processes drive parenchymal inflammation. Reversing vascular dysfunction may therefore emerge as a novel approach to diminish neuroinflammation after ischemic stroke and possibly other ischemic disorders.

Tissue-type plasminogen activator (tPA) homozygous Tyr471His mutation associates with thromboembolic disease

Tissue-type plasminogen activator (tPA) encoded by PLAT is a major mediator that promotes fibrinolysis and prevents thrombosis. Pathogenetic mutations in PLAT associated with venous thromboembolism have rarely been reported. Here, we report the first case of a homozygous point mutation c.1411T>C (p.Y471H) in PLAT leading to thromboembolic events and conduct related functional studies. The corresponding tPA mutant protein (tPA-Y471H) and wild-type tPA (tPA-WT) were synthesized in vitro, and mutant mice (PLATH/H mice) were constructed. The molecular docking and surface plasmon resonance results indicated that the mutation impeded the hydrogen-bonding interactions between the protease domain of tPA and the kringle 4 domain of plasminogen, and the binding affinity of tPA and plasminogen was significantly reduced with a difference of one order of magnitude. mRNA half-life assay showed that the half-life of tPA-Y471H was shortened. The inferior vena cava thrombosis model showed that the rate of venous thrombosis in PLATH/H mice was 80% compared with 53% in wild-type mice. Our data suggested a novel role for the protease domain of tPA in efficient plasminogen activation, and demonstrated that this tPA mutation could reduce the fibrinolysis function of the body and lead to an increased propensity for thrombosis.

Palmatine, a natural alkaloid, attenuates memory deficits and neuroinflammation in mice submitted to permanent focal cerebral ischemia

Ischemic stroke is one of the major causes of human morbidity and mortality. The pathophysiology of ischemic stroke involves complex events, including oxidative stress and inflammation, that lead to neuronal loss and cognitive deficits. Palmatine (PAL) is a naturally occurring (Coptidis rhizome) isoquinoline alkaloid that belongs to the class of protoberberines and has a wide spectrum of pharmacological and biological effects. In the present study, we evaluated the impact of Palmatine on neuronal damage, memory deficits, and inflammatory response in mice submitted to permanent focal cerebral ischemia induced by middle cerebral artery (pMCAO) occlusion. The animals were treated with Palmatine (0.2, 2 and 20 mg/kg/day, orally) or vehicle (3% Tween + saline solution) 2 h after pMCAO once daily for 3 days. Cerebral ischemia was confirmed by evaluating the infarct area (TTC staining) and neurological deficit score 24 h after pMCAO. Treatment with palmatine (2 and 20 mg/kg) reduced infarct size and neurological deficits and prevented working and aversive memory deficits in ischemic mice. Palmatine, at a dose of 2 mg/kg, had a similar effect of reducing neuroinflammation 24 h after cerebral ischemia, decreasing TNF-, iNOS, COX-2, and NF- κB immunoreactivities and preventing the activation of microglia and astrocytes. Moreover, palmatine (2 mg/kg) reduced COX-2, iNOS, and IL-1β immunoreactivity 96 h after pMCAO. The neuroprotective properties of palmatine make it an excellent adjuvant treatment for strokes due to its inhibition of neuroinflammation.

Alterations in factors associated with diabetic retinopathy combined with thrombosis: A review

Diabetic retinopathy (DR) is one of the most common and serious microvascular complications of diabetes mellitus, the incidence of which has been increasing annually, and it is the main cause of vision loss in diabetic patients and a common cause of blindness. It is now found that thrombosis plays a crucial role in the disease progression in DR patients, and the final vision loss in DR may be related to the occurrence of thrombosis in the retinal vessels, which is dominated by abnormal endothelial cell function, together with platelet dysfunction, imbalance of coagulation and fibrinolytic function, and related alterations of inflammatory factors leading to the main cause of thrombotic disease in DR patients. In this review, we examine the role between DR and thrombosis and the association of each factor, including endothelial dysfunction; platelet dysfunction; coagulation-fibrinolytic imbalance; and alterations in inflammatory factors.

Regulation of microglia polarization after cerebral ischemia

Stroke ranks second as a leading cause of death and permanent disability globally. Microglia, innate immune cells in the brain, respond rapidly to ischemic injury, triggering a robust and persistent neuroinflammatory reaction throughout the disease's progression. Neuroinflammation plays a critical role in the mechanism of secondary injury in ischemic stroke and is a significant controllable factor. Microglia activation takes on two general phenotypes: the pro-inflammatory M1 type and the anti-inflammatory M2 type, although the reality is more complex. The regulation of microglia phenotype is crucial to controlling the neuroinflammatory response. This review summarized the key molecules and mechanisms of microglia polarization, function, and phenotypic transformation following cerebral ischemia, with a focus on the influence of autophagy on microglia polarization. The goal is to provide a reference for the development of new targets for the treatment for ischemic stroke treatment based on the regulation of microglia polarization.

Targeting pyroptosis as a preventive and therapeutic approach for stroke

Stroke has caused tremendous social stress worldwide, yet despite decades of research and development of new stroke drugs, most have failed and rt-PA (Recombinant tissue plasminogen activator) is still the accepted treatment for ischemic stroke. the complexity of the stroke mechanism has led to unsatisfactory efficacy of most drugs in clinical trials, indicating that there are still many gaps in our understanding of stroke. Pyroptosis is a programmed cell death (PCD) with inflammatory properties and are thought to be closely associated with stroke. Pyroptosis is regulated by the GSDMD of the gasdermin family, which when cleaved by Caspase-1/Caspase-11 into N-GSDMD with pore-forming activity can bind to the plasma membrane to form small 10-20 nm pores, which would allow the release of inflammatory factors IL-18 and IL-1β before cell rupture, greatly exacerbating the inflammatory response. The pyroptosis occurs mainly in the border zone of cerebral infarction, and glial cells, neuronal cells and brain microvascular endothelial cells (BMECs) all undergo pyroptosis after stroke, which largely exacerbates the breakdown of the blood-brain barrier (BBB) and thus aggravates brain injury. Therefore, pyroptosis may be a good direction for the treatment of stroke. In this review, we focus on the latest mechanisms of action of pyroptosis and the process by which pyroptosis regulates stroke development. We also suggest potential therapeutic stroke drugs that target the pyroptosis pathway, providing additional therapeutic strategies for the clinical management of stroke. The role of pyroptosis after stroke. After stroke, microglia first rush to the damaged area and polarize into M1 and M2 types. Under the influence of various stimuli, microglia undergo pyroptosis, release pro-inflammatory factors, and are converted to the M1 type; astrocytes and neuronal cells also undergo pyroptosis under the stimulation of various pro-inflammatory factors, leading to astrocyte death due to increased osmotic pressure in the membrane, resulting in water absorption and swelling until rupture. BMECs, the main structural component of the BBB, also undergo pyroptosis when stimulated by pro-inflammatory factors released from microglia and astrocytes, leading to the destruction of the structural integrity of the BBB, ultimately causing more severe brain damage. In addition, GSDMD in neutrophils mainly mediate the release of NETs rather than pyroptosis, which also aggravates brain injury. IL-10=interleukin-10; TGF-β = transforming growth factor-β; IL-18=interleukin-18; IL-1β = interleukin-1β; TNF-α = tumor necrosis factor-α; iNOS=induced nitrogen monoxide synthase; MMPs=Matrix metalloproteinases; GSDMD = gasdermin D; BMECs=brain microvascular endothelial cells; BBB = blood-brain barrier.

Mechanistic and therapeutic role of Drp1 in the pathogenesis of stroke

Stroke had emerged as one of the leading causes of death and long-term disability across the globe. Emerging evidence suggests a significant increase in the incidence of stroke with age, which is further expected to increase dramatically owing to an ever-expanding elderly population. The current situation imposes a significant burden on the healthcare system and requires a deeper understanding of the underlying mechanisms and development of novel interventions. It is well established that mitochondrial dysfunction plays a pivotal role in the onset of stroke. Dynamin-related protein 1 (Drp1), is a key regulator of mitochondria fission, and plays a crucial role during the pathogenesis of stroke. Drp1 protein levels significantly increase after stroke potentially in a p38 mitogen-activated protein kinases (MAPK) dependent manner. Protein phosphatase 2A (PP2A) facilitate mitochondrial fission and cell death by dephosphorylating the mitochondrial fission enzyme Drp1 at the inhibitory phosphorylation site serine 637. Outer mitochondrial membrane A-Kinase Anchoring Proteins 1 (AKAP 1) and protein kinase A complex (PKA) complex inhibits Drp1-dependent mitochondrial fission by phosphorylating serine 637. Drp1 activation promotes the release of cytochrome C from mitochondria and therefore leads to apoptosis. In addition, Drp1 activation inhibits mitochondrial glutathione dependent free radical scavenging, which further enhances the ROS level and exacerbate mitochondrial dysfunction. Drp1 translocate p53 to mitochondrial membrane and leads to mitochondria-related necrosis. The current review article discusses the possible mechanistic pathways by which Drp1 can influence the pathogenesis of stroke. Besides, it will describe various inhibitors for Drp1 and their potential role as therapeutics for stroke in the future.

Fibrinolysis in COVID-19: Impact on Clot Lysis and Modulation of Inflammation

COVID-19 is a multisystem disease caused by SARS-CoV-2 and is associated with an imbalance between the coagulation and fibrinolytic systems. Overall, hypercoagulation, hypofibrinolysis and fibrin-clot resistance to fibrinolysis predispose patients to thrombotic and thromboembolic events. In the lungs, the virus triggers alveolar and interstitial fibrin deposition, endothelial dysfunction, and pulmonary intravascular coagulation, all events intrinsically associated with the activation of inflammation and organ injury. Adding to the pathogenesis of COVID-19, there is a positive feedback loop by which local fibrin deposition in the lungs can fuel inflammation and consequently dysregulates coagulation, a process known as immunothrombosis. Therefore, fibrinolysis plays a central role in maintaining hemostasis and tissue homeostasis during COVID-19 by cleaning fibrin clots and controlling feed-forward products of coagulation. In addition, components of the fibrinolytic system have important immunomodulatory roles, as evidenced by studies showing the contribution of Plasminogen/Plasmin (Plg/Pla) to the resolution of inflammation. Herein, we review clinical evidence for the dysregulation of the fibrinolytic system and discuss its contribution to thrombosis risk and exacerbated inflammation in severe COVID-19. We also discuss the current concept of an interplay between fibrinolysis and inflammation resolution, mirroring the well-known crosstalk between inflammation and coagulation. Finally, we consider the central role of the Plg/Pla system in resolving thromboinflammation, drawing attention to the overlooked consequences of COVID-19-associated fibrinolytic abnormalities to local and systemic inflammation.

Expression pattern and clinical value of Key RNA methylation modification regulators in ischemic stroke

Ischemic stroke (IS) is one of the major causes of death and disability worldwide, and effective diagnosis and treatment methods are lacking. RNA methylation, a common epigenetic modification, plays an important role in disease progression. However, little is known about the role of RNA methylation modification in the regulation of IS. The aim of this study was to investigate RNA methylation modification patterns and immune infiltration characteristics in IS through bioinformatics analysis. We downloaded gene expression profiles of control and IS model rat brain tissues from the Gene Expression Omnibus database. IS profiles were divided into two subtypes based on RNA methylation regulators, and functional enrichment analyses were conducted to determine the differentially expressed genes (DEGs) between the subtypes. Weighted gene co-expression network analysis was used to explore co-expression modules and genes based on DEGs. The IS clinical diagnosis model was successfully constructed and four IS characteristic genes (GFAP, GPNMB, FKBP9, and CHMP5) were identified, which were significantly upregulated in IS samples. Characteristic genes were verified by receiver operating characteristic curve and real-time quantitative PCR analyses. The correlation between characteristic genes and infiltrating immune cells was determined by correlation analysis. Furthermore, GPNMB was screened using the protein-protein interaction network, and its regulatory network and the potential therapeutic drug chloroquine were predicted. Our finding describes the expression pattern and clinical value of key RNA methylation modification regulators in IS and novel diagnostic and therapeutic targets of IS from a new perspective.

Sodium Danshensu protects against oxygen glucose deprivation/reoxygenation-induced astrocytes injury through regulating NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome and tuberous sclerosis complex-2 (TSC2)/mammalian target of rapamycin (mTOR) pathways

BACKGROUND

Cerebral ischemic stroke is a serious condition with high incidence, mortality, and associated disability. Currently, effective therapeutic options are available for ischemic stroke are limited. Accumulating evidence indicates that sodium Danshensu, mono sodium compound derived from Salvia miltiorrhiza, plays protective roles in ischemic stroke. However, the underlying protective mechanism of sodium Danshensu in cerebral ischemic stroke remains unknown.

METHODS

In the current study, we explored the role and mechanism of sodium Danshensu on astrocytes exposed to oxygen-glucose deprivation/reoxygenation (OGD/R), which mimics the process of ischemia-reperfusion. The impact of sodium Danshensu on cell viability and apoptosis after OGD/R were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-dophenyl tetrazolium bromide (MTT) assay and flow cytometry. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot were used to detect the expression of target messenger RNA (mRNA) and proteins associated with apoptosis and autophagy. The release of lactate dehydrogenase (LDH) was determined, and the production of proinflammatory cytokines were detected using enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

It was found that sodium Danshensu could significantly increase cell viability and decrease LDH release and apoptosis. Besides, it inhibited the production of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6. Sodium Danshensu also dose-dependently decreased protein and mRNA levels of nucleotide binding oligomerization NOD-like receptor pyrin domain containing 3 (NLRP3) and high mobility group box 1 (HMGB1), which play a crucial role in promoting ischemic stroke-induced cell injury. Moreover, sodium Danshensu dose-dependently upregulated Beclin 1 expression, downregulated P62 protein expression, and further increased LC3B-II/LC3B-I ratio through inducing autophagy in astrocytes. Additionally, we noticed that sodium Danshensu dose-dependently increased tuberous sclerosis complex-2 (TSC2) protein expression, while significantly reduced the levels of mammalian target of rapamycin (mTOR) in the presence of OGD/R insult.

CONCLUSIONS

These findings suggest that sodium Danshensu protects against OGD/R-induced injury by modulating the NLRP3 inflammasome and TSC2/mTOR pathways.

Treatment of Marmoset Intracerebral Hemorrhage with Humanized Anti-HMGB1 mAb

Intracerebral hemorrhage (ICH) is recognized as a severe clinical problem lacking effective treatment. High mobility group box-1 (HMGB1) exhibits inflammatory cytokine-like activity once released into the extracellular space from the nuclei. We previously demonstrated that intravenous injection of rat anti-HMGB1 monoclonal antibody (mAb) remarkably ameliorated brain injury in a rat ICH model. Therefore, we developed a humanized anti-HMGB1 mAb (OKY001) for clinical use. The present study examined whether and how the humanized anti-HMGB1 mAb ameliorates ICH injury in common marmosets. The results show that administration of humanized anti-HMGB1 mAb inhibited HMGB1 release from the brain into plasma, in association with a decrease of 4-hydroxynonenal (4-HNE) accumulation and a decrease in cerebral iron deposition. In addition, humanized anti-HMGB1 mAb treatment resulted in a reduction in brain injury volume at 12 d after ICH induction. Our in vitro experiment showed that recombinant HMGB1 inhibited hemoglobin uptake by macrophages through CD163 in the presence of haptoglobin, suggesting that the release of excess HMGB1 from the brain may induce a delay in hemoglobin scavenging, thereby allowing the toxic effects of hemoglobin, heme, and Fe2+ to persist. Finally, humanized anti-HMGB1 mAb reduced body weight loss and improved behavioral performance after ICH. Taken together, these results suggest that intravenous injection of humanized anti-HMGB1 mAb has potential as a novel therapeutic strategy for ICH.

Exosome in Crosstalk between Inflammation and Angiogenesis: A Potential Therapeutic Strategy for Stroke

The endothelial dysfunction, associated with inflammation and vascular permeability, remains the key event in the pathogenesis of cerebral ischemic stroke. Angiogenesis is essential for neuroprotection and neural repair following stroke. The neuroinflammatory reaction plays a vital role in stroke, and inhibition of inflammation contributes to establishing an appropriate external environment for angiogenesis. Exosomes are the heterogeneous population of extracellular vesicles which play critical roles in intercellular communication through transmitting various proteins and nucleic acids to nearby and distant recipient cells by body fluids and circulation. Recent reports have shown that exosomal therapy is a valuable and potential treatment strategy for stroke. In this review, we discussed the exosomes in complex interaction mechanisms of angiogenesis and inflammation following stroke as well as the challenges of exosomal studies such as secretion, uptake, modification, and application.

Need for a Paradigm Shift in the Treatment of Ischemic Stroke: The Blood-Brain Barrier

Blood-brain barrier (BBB) integrity is essential to maintaining brain health. Aging-related alterations could lead to chronic progressive leakiness of the BBB, which is directly correlated with cerebrovascular diseases. Indeed, the BBB breakdown during acute ischemic stroke is critical. It remains unclear, however, whether BBB dysfunction is one of the first events that leads to brain disease or a down-stream consequence. This review will focus on the BBB dysfunction associated with cerebrovascular disease. An added difficulty is its association with the deleterious or reparative effect, which depends on the stroke phase. We will first outline the BBB structure and function. Then, we will focus on the spatiotemporal chronic, slow, and progressive BBB alteration related to ischemic stroke. Finally, we will propose a new perspective on preventive therapeutic strategies associated with brain aging based on targeting specific components of the BBB. Understanding BBB age-evolutions will be beneficial for new drug development and the identification of the best performance window times. This could have a direct impact on clinical translation and personalised medicine.

Annexin V-Modified Platelet-Biomimetic Nanomedicine for Targeted Therapy of Acute Ischemic Stroke

Thromboembolic stroke is typically characterized by the activation of platelets, resulting in thrombus in the cerebral vascular system, leading to high morbidity and mortality globally. Intravenous thrombolysis by tissue plasminogen activator (tPA) administration within 4.5 h from the onset of symptoms is providing a standard therapeutic strategy for ischemic stroke, but this reagent simultaneously shows potential serious adverse effects, e.g., hemorrhagic transformation. Herein, a novel delivery platform based on Annexin V and platelet membrane is developed for tPA (APLT-PA) to enhance targeting efficiency, therapeutic effects, and reduce the risk of intracerebral hemorrhage in acute ischemic stroke. After preparation by extrusion of platelet membrane and subsequent insertion of Annexin V to liposomes, APLT-PA exhibits a high targeting efficiency to activated platelet in vitro and thrombosis site in vivo, due to the binding to phosphatidylserine (PS) and activated platelet membrane proteins. One dose of APLT-PA leads to obvious thrombolysis and significant improvement of neurological function within 7 days in mice with photochemically induced acute ischemic stroke. This study provides a novel, safe platelet-biomimetic nanomedicine for precise thrombolytic treatment of acute ischemic stroke, and offers new theories for the design and exploitation of cell-mimetic nanomedicine for diverse biomedical applications.

Low α2-Plasmin Inhibitor Antigen Levels on Admission Are Associated With More Severe Stroke and Unfavorable Outcomes in Acute Ischemic Stroke Patients Treated With Intravenous Thrombolysis

Background

Intravenous administration of recombinant tissue plasminogen activator (rt-PA) fails to succeed in a subset of acute ischemic stroke (AIS) patients, while in approximately 6–8% of cases intracerebral hemorrhage (ICH) occurs as side effect.

Objective

Here, we aimed to investigate α2-plasmin inhibitor (α2-PI) levels during thrombolysis and to find out whether they predict therapy outcomes in AIS patients.

Patients/Methods

In this prospective, observational study, blood samples of 421 AIS patients, all undergoing i.v. thrombolysis by rt-PA within 4.5 h of their symptom onset, were taken before and 24 h after thrombolysis. In a subset of patients (n = 131), blood was also obtained immediately post-lysis. α2-PI activity and antigen levels were measured by chromogenic assay and an in-house ELISA detecting all forms of α2-PI. α2-PI Arg6Trp polymorphism was identified in all patients. Stroke severity was determined by NIHSS on admission and day 7. Therapy-associated ICH was classified according to ECASSII. Long-term outcomes were defined at 3 months post-event by the modified Rankin Scale (mRS).

Results

Median α2-PI activity and antigen levels showed a significant drop immediately post-lysis and increased to subnormal levels at 24 h post-event. Admission α2-PI levels showed a significant negative stepwise association with stroke severity. Patients with favorable long-term outcomes (mRS 0–1) had significantly higher admission α2-PI antigen levels (median:61.6 [IQR:55.9–70.5] mg/L) as compared to patients with poor outcomes (mRS 2–5: median:59.7 [IQR:54.5–69.1] and mRS 6: median:56.0 [IQR:48.5–61.0] mg/L, p < 0.001). In a Kaplan–Meier survival analysis, patients with an α2-PI antigen in the highest quartile on admission showed significantly better long-term survival as compared to those with α2-PI antigen in the lowest quartile (HR: 4.54; 95%CI:1.92–10.8, p < 0.001); however, in a multivariate analysis, a low admission α2-PI antigen did not prove to be an independent risk factor of poor long-term outcomes. In patients with therapy-related ICH (n = 34), admission α2-PI antigen levels were significantly, but only marginally, lower as compared to those without hemorrhage.

Conclusions

Low α2-PI antigen levels on admission were associated with more severe strokes and poor long-term outcomes in this cohort. Our results suggest that in case of more severe strokes, α2-PI may be involved in the limited efficacy of rt-PA thrombolysis.

Molecular Detection of Venous Thrombosis in Mouse Models Using SPECT/CT

The efficacy of thrombolysis is inversely correlated with thrombus age. During early thrombogenesis, activated factor XIII (FXIIIa) cross-links α2-AP to fibrin to protect it from early lysis. This was exploited to develop an α2-AP-based imaging agent to detect early clot formation likely susceptible to thrombolysis treatment. In this study, this imaging probe was improved and validated using 111In SPECT/CT in a mouse thrombosis model. In vitro fluorescent- and 111In-labelled imaging probe-to-fibrin cross-linking assays were performed. Thrombus formation was induced in C57Bl/6 mice by endothelial damage (FeCl3) or by ligation (stenosis) of the infrarenal vena cava (IVC). Two or six hours post-surgery, mice were injected with 111In-DTPA-A16 and ExiTron Nano 12000, and binding of the imaging tracer to thrombi was assessed by SPECT/CT. Subsequently, ex vivo IVCs were subjected to autoradiography and histochemical analysis for platelets and fibrin. Efficient in vitro cross-linking of A16 imaging probe to fibrin was obtained. In vivo IVC thrombosis models yielded stable platelet-rich thrombi with FeCl3 and fibrin and red cell-rich thrombi with stenosis. In the stenosis model, clot formation in the vena cava corresponded with a SPECT hotspot using an A16 imaging probe as a molecular tracer. The fibrin-targeting A16 probe showed specific binding to mouse thrombi in in vitro assays and the in vivo DVT model. The use of specific and covalent fibrin-binding probes might enable the clinical non-invasive imaging of early and active thrombosis.

Exploring biomarkers for ischemic stroke through integrated microarray data analysis

Stroke is the third leading cause of disability-adjusted life years worldwide, and drugs available for its treatment are limited. This study aimed to explore high-confidence candidate genes associated with ischemic stroke (IS) through bioinformatics analysis and identify potential diagnostic biomarkers and gene-drug interactions. Weighted gene coexpression network analysis (WGCNA) and differentially expressed genes (DEGs) were integrated to identify overlapping genes. Then, high-confidence candidate genes were screened by least absolute shrinkage and selection operator (LASSO) regression. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic value of high-confidence candidate genes as biomarkers for IS. The NetworkAnalyst database was used to construct the TF-gene network and miRNA-TF regulatory network of the high-confidence candidate genes. The DGIdb database was used to identified gene-drug interactions. Through the comprehensive analysis of GSE58294 and GSE16561, 10 high-confidence candidate genes were identified by LASSO regression: ARG1, LY96, ABCA1, SLC22A4, CD163, TPM2, SLC25A42, ID3, FAM102A and CD79B. FAM102A had the highest diagnostic value, and the area under curve (AUC), sensitivity and specificity values were 0.974, 0.919 and 0.936, respectively. The HPA database demonstrated that 10 high-confidence candidate genes were expressed in the brain and blood in normal humans. Finally, DGIdb database analysis identified 8 gene-drug interactions. We identified IS-related diagnostic biomarkers and gene-drug interactions that potentially provide new insights into the diagnosis and treatment of IS.

Investigational drugs for ischemic stroke: what's in the clinical development pipeline for acute phase and prevention?

INTRODUCTION

Stroke is a leading cause of disability and mortality and its burden expected to increase. The only approved drug for acute ischemic stroke is the intravenous thrombolytic alteplase. The risk of bleeding complications is one of the reasons for the undertreatment of eligible patients. Numerous drugs are currently being developed to improve safety-efficacy.

AREAS COVERED

We reviewed literature from January 1^st, 2000, to 15^th January 2022 for the development and testing of novel drugs with the aim of targeting treatment at prevention of ischemic stroke: PubMed, MEDLINE, Google Scholar, and ClinicalTrial.gov.

EXPERT OPINION

The pathophysiology of ischemic stroke involves multiple pathways causing cerebral artery obstruction and brain tissue ischemia. Data suggest that tenecteplase is a more promising fibrinolytic agent with a superior efficacy-safety profile, compared to the currently approved alteplase. Current guidelines consider a short-term cycle of mannitol or hypertonic saline to be advisable in patients with space-occupying hemispheric infarction. Regarding primary and secondary prevention, research is primarily focused on identifying mechanisms to improve the safety-efficacy profile using a "hemostasis-sparing" approach. Further evaluation on those agents that have already shown promise for their risk/benefit profiles, would benefit greatly a neurologist's capacity to successfully prevent and treat ischemic stroke patients.

Effect of Acupuncture and Rehabilitation Therapy on the Recovery of Neurological Function and Prognosis of Stroke Patients

BACKGROUND

Stroke is a common cerebrovascular disease among the middle-aged and elderly, which can lead to a series of neurological disorders. Acupuncture is an important part of traditional Chinese medicine, with great value in improving the neurological deficits of stroke patients. In addition, rehabilitation therapy is also of great significance for alleviating the neurological deficits of patients and improving their activities of daily living.

OBJECTIVE

To explore the effect of acupuncture and moxibustion combined with rehabilitation therapy on the recovery of neurological function and prognosis of stroke patients.

METHODS

The case data of 100 stroke patients treated in the Wuhan Hospital of Traditional Chinese Medicine from January 2019 to July 2021 were analyzed retrospectively. According to the treatment plan patients received, they were divided into the following two groups: an observation group (n = 52) treated with acupuncture combined with rehabilitation therapy and a control group (n = 48) treated with rehabilitation therapy alone. The two groups were compared in terms of the following items: therapeutic efficacy, plasma levels of cortisol (Cor) and neuropeptide Y (NPY), nerve function, motor function, balance ability, self-care ability, swallowing function, negative emotions, and quality of life.

RESULTS

The therapeutic effect of the observation group was significantly higher than that of the control group (P < 0.05). The levels of Cor and NPY, as well as the neurological function, motor function, balance ability, self-care ability, swallowing function, and negative emotions, were not significantly different between the two groups before treatment (P > 0.05). While after intervention, all the above indexes improved in both groups, with better improvements in the observation group compared with the control group (P < 0.05). And the various dimensions concerning the quality of life of patients were also significantly better in the observation group when compared with the control group.

CONCLUSION

Acupuncture of traditional Chinese medicine combined with rehabilitation therapy has outstanding effects in stroke treatment and can effectively improve the neurological function, prognosis, and quality of life of patients, which is worthy of clinical promotion.

Breaking the fibrinolytic speed limit with microwheel co-delivery of tissue plasminogen activator and plasminogen

BACKGROUND

To reestablish blood flow in vessels occluded by clots, tissue plasminogen activator (tPA) can be used; however, its efficacy is limited by transport to and into a clot and by the depletion of its substrate, plasminogen.

OBJECTIVES

To overcome these rate limitations, a platform was designed to co-deliver tPA and plasminogen based on microwheels (µwheels), wheel-like assemblies of superparamagnetic colloidal beads that roll along surfaces at high speeds.

METHODS

The biochemical speed limit was determined by measuring fibrinolysis of plasma clots at varying concentrations of tPA (10-800 nM) and plasminogen (1-6 µM). Biotinylated magnetic mesoporous silica nanoparticles were synthesized and bound to streptavidin-coated superparamagnetic beads to make studded beads. Studded beads were loaded with plasminogen and tPA was immobilized on their surface. Plasminogen release and tPA activity were measured on the studded beads. Studded beads were assembled into µwheels with rotating magnetic fields and fibrinolysis of plasma clots was measured in a microfluidic device.

RESULTS

The biochemical speed limit for plasma clots was ~15 µm/min. Plasminogen-loaded, tPA-immobilized µwheels lyse plasma clots at rates comparableto the biochemical speed limit. With the addition of a corkscrew motion, µwheels penetrate clots, thereby exceeding the biochemical speed limit (~20 µm/min) and achieving lysis rates 40-fold higher than 50 nM tPA.

CONCLUSIONS

Co-delivery of an immobilized enzyme and its substrate via a microbot capable of mechanical work has the potential to target and rapidly lyse clots that are inaccessible by mechanical thrombectomy devices or recalcitrant to systemic tPA delivery.

Mitochondrial quality control in stroke: From the mechanisms to therapeutic potentials

Mitochondrial damage is a critical contributor to stroke‐induced injury, and mitochondrial quality control (MQC) is the cornerstone of restoring mitochondrial homeostasis and plays an indispensable role in alleviating pathological process of stroke. Mitochondria quality control promotes neuronal survival via various adaptive responses for preserving mitochondria structure, morphology, quantity and function. The processes of mitochondrial fission and fusion allow for damaged mitochondria to be segregated and facilitate the equilibration of mitochondrial components such as DNA, proteins and metabolites. The process of mitophagy is responsible for the degradation and recycling of damaged mitochondria. This review aims to offer a synopsis of the molecular mechanisms involved in MQC for recapitulating our current understanding of the complex role that MQC plays in the progression of stroke. Speculating on the prospect that targeted manipulation of MQC mechanisms may be exploited for the rationale design of novel therapeutic interventions in the ischaemic stroke and haemorrhagic stroke. In the review, we highlight the potential of MQC as therapeutic targets for stroke treatment and provide valuable insights for clinical strategies.

CircDLGAP4 overexpression relieves oxygen-glucose deprivation-induced neuronal injury by elevating NEGR1 through sponging miR-503-3p

Circular RNAs (circRNAs) have been reported to play vital regulatory roles in human diseases. However, the functions of circRNAs in ischemic stroke (IS) are limited. In this study, we aimed to explore the functions and mechanisms of circRNA DLG associated protein 4 (circDLGAP4) in IS development. Oxygen-glucose deprivation (OGD)-treated HCN-2 cells were used to mimic IS environment in vitro. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was used to detect the levels of circDLGAP4, microRNA-503-3p (miR-503-3p) and neuronal growth regulator 1 (NEGR1) mRNA. RNase R assay was conducted to analyze the stability of circDLGAP4. Cell Counting Kit-8 (CCK-8) assay and flow cytometry analysis were adopted for cell viability and death, respectively. Western blot assay was performed for protein levels. Enzyme-linked immunosorbent assay (ELISA) kits were used to examine the concentrations of inflammatory cytokines. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay were employed to analyze the relationships among circDLGAP4, miR-503-3p and NEGR1. CircDLGAP4 level was declined in HCN-2 cells after OGD treatment. CircDLGAP4 overexpression promoted cell viability and suppressed cell death and inflammatory cytokine concentrations in OGD-treated HCN-2 cells. CircDLGAP4 acted as the sponge for miR-503-3p and the impacts of circDLGAP4 overexpression on cell viability, death and inflammation in OGD-treated HCN-2 cells were reversed by miR-503-3p elevation. Furthermore, NEGR1 was the target gene of miR-503-3p. MiR-503-3p inhibition ameliorated OGD-induced HCN-2 cell impairments, but NEGR1 knockdown abolished the effects. CircDLGAP4 alleviated OGD-induced HCN-2 cell damage by regulating miR-503-3p/NEGR1 axis.

Submassive Pulmonary Embolism: Current Perspectives and Future Directions

Submassive pulmonary embolism (PE) lies on a spectrum of disease severity between standard and high-risk disease. By definition, patients with submassive PE have a worse outcome than the majority of those with standard-risk PE, who are hemodynamically stable and lack imaging or laboratory features of cardiac dysfunction. Systemic thrombolytic therapy has been proven to reduce mortality in patients with high-risk disease; however, its use in submassive PE has not demonstrated a clear benefit, with haemodynamic improvements being offset by excess bleeding. Furthermore, meta-analyses have been confusing, with conflicting results on overall survival and net gain. As such, significant interest remains in optimising thrombolysis, with recent efforts in catheter-based delivery as well as upcoming studies on reduced systemic dosing. Recently, long-term cardiorespiratory limitations following submassive PE have been described, termed post-PE syndrome. Studies on the ability of thrombolytic therapy to prevent this condition also present conflicting evidence. In this review, we aim to clarify the current evidence with respect to submassive PE management, and also to highlight shortcomings in current definitions and prognostic factors. Additionally, we discuss novel therapies currently in preclinical and early clinical trials that may improve outcomes in patients with submassive PE.

Thrombolytic strategies for ischemic stroke in the thrombectomy era

Twenty-five years ago, intravenous thrombolysis has revolutionized the care of patients with acute ischemic stroke. Since 2015, randomized clinical trials have demonstrated that mechanical thrombectomy improves functional outcome in stroke patients over intravenous thrombolysis alone. More recently, three randomized clinical trials have suggested that mechanical thrombectomy alone is noninferior to a combined strategy with both intravenous thrombolysis and mechanical thrombectomy. In the present review, we will present the last clinical and preclinical studies on the use of thrombolysis in stroke patients in the modern thrombectomy era. At the cost of a potential increased risk of hemorrhagic transformation, thrombolysis may promote arterial recanalization before thrombectomy, improve the rate of successful recanalization after thrombectomy, and restore microcirculation patency downstream of the main thrombus. Besides, new thrombolytic strategies targeting tissue-type plasminogen activator resistant thrombi are being developed, which could strengthen the beneficial effects of thrombolysis without carrying additional pro-hemorrhagic effects. For instance, tenecteplase has shown improved rate of recanalization compared with tissue-type plasminogen activator (alteplase). Beyond fibrinolysis, DNA- and von Willebrand factor-targeted thrombolytic strategies have shown promising results in experimental models of ischemic stroke. New combined strategies, improved thrombolytics, and dedicated clinical trials in selected patients are eagerly awaited to further improve functional outcome in stroke.

Evaluation of Zhilong Huoxue Tongyu capsule in the treatment of acute cerebral infarction: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Zhilong Huoxue Tongyu capsule (ZL) is a Chinese patent medicine and used for the treatment of acute cerebral infarction (ACI) and its clinical application has gradually been widely recognized in China. However, the effects of ZL for patients with ACI have never been systematically evaluated.

PURPOSE

A systematic review and meta-analysis was performed to evaluate the efficacy of ZL in ACI.

STUDY DESIGN

A systematic review and meta-analysis of randomized clinical trials (RCTs).

MATERIALS AND METHODS

A systematic review and meta-analysis were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The comprehensive literature search was accomplished in 6 electronic databases to find relevant randomized controlled trials from their inception until October 31, 2020. The Cochrane Handbook for Systematic Reviews of Interventions was used for methodological quality and independent evaluation. Review Manager 5.3 was used to analyze all the data obtained. The Clinical Effective Rate (CER) was the primary outcome, and the National Institutes of Health Stroke Score (NIHSS), Barthel Index (BI), and Modified Rankin Scale (MRS) were the secondary outcomes.

RESULTS

Seven clinical studies recruiting 571 eligible patients were included in this meta-analysis. The results of meta-analysis suggested that compared with conventional treatment alone, ZL combined with conventional treatment significantly improved CER (RR = 1.20, 95% CI: 1.12-1.29, p < 0.00001), decrease National Institutes of Health Stroke Scale Score (NIHSS) (MD = -2.60, 95% CI: -3.41-1.79, p < 0.00001), Barthel Index (BI) (MD = -9.75, 95% CI: 7.15-12.36, p < 0.00001) and Modified Rankin Scale (MRS) (MD = -0.57, 95% CI: -0.84-0.30, p < 0.00001). There were no reported adverse events in the studies. Most results were robust and the quality of evidence was from moderate to low.

CONCLUSION

ZL combined with conventional treatment can improve the short-term outcomes of ACI patients, indicating ZL is a promising treatment choice for ACI and may be used as adjunctive treatment to the conventional treatment of ACI. However, due to the limitations of included clinical trials, high-quality clinical trials with longer follow-ups are still needed to further assess the effectiveness and safety of ZL for ACI patients.

Therapeutic Applications of Stem Cells and Extracellular Vesicles in Emergency Care: Futuristic Perspectives

Regenerative medicine (RM) is an interdisciplinary field that aims to repair, replace or regenerate damaged or missing tissue or organs to function as close as possible to its physiological architecture and functions. Stem cells, which are undifferentiated cells retaining self-renewal potential, excessive proliferation and differentiation capacity into offspring or daughter cells that form different lineage cells of an organism, are considered as an important part of the RM approaches. They have been widely investigated in preclinical and clinical studies for therapeutic purposes. Extracellular vesicles (EVs) are the vital mediators that regulate the therapeutic effects of stem cells. Besides, they carry various types of cargo between cells which make them a significant contributor of intercellular communication. Given their role in physiological and pathological conditions in living cells, EVs are considered as a new therapeutic alternative solution for a variety of diseases in which there is a high unmet clinical need. This review aims to summarize and identify therapeutic potential of stem cells and EVs in diseases requiring acute emergency care such as trauma, heart diseases, stroke, acute respiratory distress syndrome and burn injury. Diseases that affect militaries or societies including acute radiation syndrome, sepsis and viral pandemics such as novel coronavirus disease 2019 are also discussed. Additionally, featuring and problematic issues that hamper clinical translation of stem cells and EVs are debated in a comparative manner with a futuristic perspective. Graphical Abstract.

l-Borneol Exerted the Neuroprotective Effect by Promoting Angiogenesis Coupled With Neurogenesis via Ang1-VEGF-BDNF Pathway

At present, Stroke is still one of the leading causes of population death worldwide and leads to disability. Traditional Chinese medicine plays an important role in the prevention or treatment of stroke. l-borneol, a traditional Chinese medicine, has been used in China to treat stroke for thousands of years. However, its mechanism of action is unclear. After cerebral ischemia, promoting angiogenesis after cerebral ischemia and providing nutrition for the infarct area is an important strategy to improve the damage in the ischemic area, but it is also essential to promote neurogenesis and replenish new neurons. Here, our research shows that l-borneol can significantly improve the neurological deficits of pMCAO model rats, reduce cerebral infarction, and improve the pathological damage of cerebral ischemia. and significantly increase serum level of Ang-1 and VEGF, and significantly decrease level of ACE and Tie2 to promote angiogenesis. PCR and WB showed the same results. Immunohistochemistry also showed that l-borneol can increase the number of CD34 positive cells, further verifying that l-borneol can play a neuroprotective effect by promoting angiogenesis after cerebral ischemia injury. In addition, l-borneol can significantly promote the expression level of VEGF, BDNF and inhibit the expression levels of TGF-β1 and MMP9 to promote neurogenesis. The above suggests that l-borneol can promote angiogenesis coupled neurogenesis by regulating Ang1-VEGF-BDNF to play a neuroprotective effect. Molecular docking also shows that l-borneol has a very high binding rate with the above target, which further confirmed the target of l-borneol to improve cerebral ischemic injury. These results provide strong evidence for the treatment of cerebral ischemia with l-borneol and provide reference for future research.

Targeted nano-delivery strategies for facilitating thrombolysis treatment in ischemic stroke

Ischemic stroke is one of the major causes of severe disability and death worldwide. It is mainly caused by a sudden reduction in cerebral blood flow due to obstruction of the supplying vessel by thrombi and subsequent initiation of a complex cascade of pathophysiological changes, which ultimately lead to brain ischemia and even irreversible infarction. Thus, timely and effective thrombolysis therapy remains a mainstay for acute ischemic stroke treatment. Tissue plasminogen activator (tPA), the only thrombolytic agent approved globally, provides substantial benefits by exerting a fibrinolysis effect, recovering the blood supply in occluded vessels and, thereby, salvaging the ischemic tissue. However, the clinical application of tPA was limited because of a few unsolved issues, such as a narrow therapeutic window, hemorrhagic complications, and limited thrombolytic efficacy, especially, for large thrombi. With the prosperous development of nanotechnology, a series of targeted delivery strategies and nanocomposites have been extensively investigated for delivering thrombolytic agents to facilitate thrombolysis treatment. Excitingly, numerous novel attempts have been reported to be effective in extending the half-life, targeting the thrombus site, and improving the thrombolytic efficacy in preclinical models. This article begins with a brief introduction to ischemic stroke, then describes the current state of thrombolysis treatment and, finally, introduces the application of various nanotechnology-based strategies for targeted delivery of thrombolytic agents. Representative studies are reviewed according to diverse strategies and nano-formulations, with the aim of providing integrated and up-to-date information and to improve the development of thrombolysis treatment for stroke patients.