Update on the effects of treatment with recombinant tissue-type plasminogen activator (rt-PA) in acute ischemic stroke

Potential Roles of Natural Antioxidants in Modulating Neurodegenerative Disease Pathways

Neurodegenerative diseases, including Alzheimer's, Parkinson's, and amyotrophic lateral sclerosis, are increasingly prevalent among aging populations. Oxidative stress contributes to these diseases, leading to cellular damage and neuronal death. Natural antioxidants are being explored as preventive measures. This study aims to assess the effectiveness of natural antioxidants in delaying the onset or progression of neurodegenerative diseases by identifying their specific mechanisms of action. A comprehensive review of existing literature was conducted, focusing on studies that examine the role of natural antioxidants in neuroprotection. Key natural antioxidants, including flavonoids, polyphenls, vitamins C and E, and omega-3 fatty acids, were reviewed and analyzed for their bioavailability, mechanisms of action, and outcomes in both in vitro and in vivo studies. Additionally, clinical trials involving human subjects were considered to provide insights into the translational implications of antioxidant consumption. The findings suggest that several natural antioxidants exhibit neuroprotective properties by modulating oxidative stress, reducing inflammation, and promoting neuronal survival. For instance, flavonoids such as quercetin and resveratrol have shown promise in enhancing cognitive function and mitigating the pathophysiological alterations associated with neurodegeneration. In clinical studies, higher intakes of dietary antioxidants were correlated with a reduced risk of developing neurodegenerative disorders. Natural antioxidants offer potential for preventing neurodegenerative diseases by counteracting oxidative stress and maintaining cellular integrity. Overall, our report recommends that further research is needed to optimize dosages and understand their long-term benefits.

Prognostic Impact of Neutrophil-to-Lymphocyte Ratio in Ischemic Stroke

Background/objective: Studies suggest that the neutrophil/lymphocyte ratio (NLR) may be a prognostic marker for different diseases with inflammatory components. This study aimed to quantify the NLR in individuals affected by different subtypes and severities of ischemic stroke and associated it with risk factors and treatment, and compared the results with data from healthy individuals. Methods: Clinical and laboratory data from medical records of patients over 18 years of age, victims of ischemic stroke, were collected. Data included leukocyte count and subtype, topography, risk factors, treatment and severity of stroke. For comparison, the number of leukocytes in healthy individuals was also quantified. NLR was determined by dividing the number of neutrophils by the number of lymphocytes. Results: A total of 218 patients were included, 194 stroke patients and 24 healthy individuals. Among all stroke patients, 45% had NLR values > 4 and 35% had values between 2 and 4; otherwise, 71% of healthy individuals had NRL < 2. The data also showed that the greater the severity of the stroke, measured by the NIHSS scale, the higher the NLR, at 24 and 72 h after the stroke. Among the stroke subtypes evaluated, the one with the lowest NLR values was small vessel stroke. Finally, the risk factors for stroke, its topography and treatment were not associated with NLR values. Conclusions: NLR is associated with stroke severity but does not correlate with stroke risk factors, topography, and treatment. The NLR may serve as a marker of stroke severity.

From Gut to Brain: Unraveling the Intricate Link Between Microbiome and Stroke

Stroke, a neurological disorder, is intricately linked to the gut microbiota, influencing microbial composition and elevating the risk of ischemic stroke. The neuroprotective impact of short-chain fatty acids (SCFAs) derived from dietary fiber fermentation contrasts with the neuroinflammatory effects of lipopolysaccharide (LPS) from gut bacteria. The pivotal role of the gut-brain axis, facilitating bidirectional communication between the gut and the brain, is crucial in maintaining gastrointestinal equilibrium and influencing cognitive functions. An in-depth understanding of the interplay among the gut microbiota, immune system, and neurological outcomes in stroke is imperative for devising innovative preventive and therapeutic approaches. Strategies such as dietary adjustments, probiotics, prebiotics, antibiotics, or fecal transplantation offer promise in modulating stroke outcomes. Nevertheless, comprehensive research is essential to unravel the precise mechanisms governing the gut microbiota's involvement in stroke and to establish effective therapeutic interventions. The initiation of large-scale clinical trials is warranted to assess the safety and efficacy of interventions targeting the gut microbiota in stroke management. Tailored strategies that reinstate eubiosis and foster a healthy gut microbiota hold potential for both stroke prevention and treatment. This review underscores the gut microbiota as a promising therapeutic target in stroke and underscores the need for continued research to delineate its precise role and develop microbiome-based interventions effectively.

Risk assessment of mechanic thrombectomy on post-stroke seizures: a systematical review and meta-analysis

PURPOSE

We conducted a systematic review and meta-analysis to evaluate the risk of early and late onset seizures following stroke mechanic thrombectomy (MT) compared with other systematic thrombolytic strategies.

METHODS

A literature search was conducted to identify articles covering databases (PubMed, Embase, and Cochrane Library) published from 2000 to 2022. The primary outcome was the incidence of post-stroke epilepsy or seizures following MT or in combination with intravenous thrombolytics therapy. Risk of bias was assessed by recording study characteristics. The study was conducted according to the PRISMA guidelines.

RESULTS

There were 1346 papers in the search results, and 13 papers were included in the final review.We identified 29,793 patients with stroke, of which 695 had seizures. Pooled incidence of post-stroke seizures had no significant difference between mechanic thrombolytic group and other thrombolytic strategy group (OR=0.95 (95%CI= 0.75-1.21); Z=0.43; p=0.67). In subgroup analysis, mechanic group have a lower risk of post-stroke early onset of seizures (OR=0.59 (95%CI=0.36-0.95); Z=2.18; p<0.05) but showed no significant difference in post-stroke late onset of seizures (OR=0.95 (95%CI= 0.68-1.32); Z=0.32; p=0.75).

CONCLUSIONS

MT may be associated with a lower risk of post-stroke early onset of seizures, despite MT does not affect the pooled incidence of post-stroke seizures compared with other systematic thrombolytic strategies.

Significance of Immune Status of SARS-CoV-2 Infected Patients in Determining the Efficacy of Therapeutic Interventions

Coronavirus disease 2019 (COVID-19) is now being investigated for its distinctive patterns in the course of disease development which can be indicated with miscellaneous immune responses in infected individuals. Besides this series of investigations on the pathophysiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), significant fundamental immunological and physiological processes are indispensable to address clinical markers of COVID-19 disease and essential to identify or design effective therapeutics. Recent developments in the literature suggest that deficiency of type I interferon (IFN) in serum samples can be used to represent a severe progression of COVID-19 disease and can be used as the basis to develop combined immunotherapeutic strategies. Precise control over inflammatory response is a significant aspect of targeting viral infections. This account presents a brief review of the pathophysiological characteristics of the SARS-CoV-2 virus and the understanding of the immune status of infected patients. We further discuss the immune system’s interaction with the SARS-CoV-2 virus and their subsequent involvement of dysfunctional immune responses during the progression of the disease. Finally, we highlight some of the implications of the different approaches applicable in developing promising therapeutic interventions that redirect immunoregulation and viral infection.

Dodging blood brain barrier with "nano" warriors: Novel strategy against ischemic stroke

Ischemic stroke (IS) is one of the leading causes of death and disability resulting in inevitable burden globally. Ischemic injury initiates cascade of pathological events comprising energy dwindling, failure of ionic gradients, failure of blood brain barrier (BBB), vasogenic edema, calcium over accumulation, excitotoxicity, increased oxidative stress, mitochondrial dysfunction, inflammation and eventually cell death. In spite of such complexity of the disease, the only treatment approved by US Food and Drug Administration (FDA) is tissue plasminogen activator (t-PA). This therapy overcome blood deficiency in the brain along with side effects of reperfusion which are responsible for considerable tissue injury. Therefore, there is urgent need of novel therapeutic perspectives that can protect the integrity of BBB and salvageable brain tissue. Advancement in nanomedicine is empowering new approaches that are potent to improve the understanding and treatment of the IS. Herein, we focus nanomaterial mediated drug delivery systems (DDSs) and their role to bypass and cross BBB especially via intranasal drug delivery. The various nanocarriers used in DDSs are also discussed. In a nut shell, the objective is to provide an overview of use of nanomedicine in the diagnosis and treatment of IS to facilitate the research from benchtop to bedside.

Endothelial dysfunction and immunothrombosis as key pathogenic mechanisms in COVID-19

Coronavirus disease 2019 (COVID-19) is a clinical syndrome caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Patients with severe disease show hyperactivation of the immune system, which can affect multiple organs besides the lungs. Here, we propose that SARS-CoV-2 infection induces a process known as immunothrombosis, in which activated neutrophils and monocytes interact with platelets and the coagulation cascade, leading to intravascular clot formation in small and larger vessels. Microthrombotic complications may contribute to acute respiratory distress syndrome (ARDS) and other organ dysfunctions. Therapeutic strategies aimed at reducing immunothrombosis may therefore be useful. Several antithrombotic and immunomodulating drugs have been proposed as candidates to treat patients with SARS-CoV-2 infection. The growing understanding of SARS-CoV-2 infection pathogenesis and how it contributes to critical illness and its complications may help to improve risk stratification and develop targeted therapies to reduce the acute and long-term consequences of this disease.

Effect of intravenous thrombolysis with alteplase on clinical efficacy, inflammatory factors, and neurological function in patients with acute cerebral infarction

This study aimed to explore the effect of intravenous thrombolysis with alteplase on clinical efficacy, inflammatory factors, and neurological function in patients with acute cerebral infarction. A total of 120 patients with acute cerebral infarction were divided into two groups by the random number table method, with 60 patients in each group: observation group (intravenous thrombolysis with alteplase) and control group (intravenous thrombolysis with batroxobin). The clinical efficacy after a 14-day treatment was observed. Serum C-reactive protein (CRP), tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), CD62p, GMP-140, and neuron-specific enolase (NSE) were measured. Scores of National Institutes of Health Stroke Scale (NIHSS), Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA) were determined. The total effective rate in the observation group was 81.67%, which was higher than the 61.67% in the control group (P<0.05). The improvement of inflammatory factors (CRP, TNF-α, IL-6, CD62p, GMP-140, and NSE), NIHSS, MMSE, and MoCA in the observation group was superior to that in the control group (all P<0.05). The modified Rankin scale at three months after hospital discharge in the observation group was lower than that in the control group (P<0.01). Intravenous thrombolysis with alteplase for acute cerebral infarction can enhance the clinical efficacy, alleviate inflammatory response and brain injury, and improve cognitive function, which is worthy of further clinical application and study.

Effectiveness and safety of different doses of tenecteplase in the treatment of acute ischemic stroke: A protocol for systematic review and meta-analysis

BACKGROUND

Tenecteplase is a modified recombinant tissue-plasminogen activator, which is effective and safe in the treatment of acute ischemic stroke. However, the therapeutic dose of tenecteplase has been controversial. The purpose of this study is to systematically investigate the efficacy and safety of different doses of tenecteplase thrombolytic therapy for acute ischemic stroke.

METHODS

Computer retrieval of English databases (PubMed, EMBASE, Web of Science, the Cochrane Library) and Chinese databases (CNKI, Wanfang, Viper, and Chinese Biomedical Database) is conducted for a randomized controlled clinical study on thrombolytic treatment of acute ischemic stroke with different doses of tenecteplase from the establishment of the database to October 2020. Two researchers independently conduct data extraction and literature quality evaluation on the quality of the included studies, and meta-analysis is conducted on the included literatures using RevMan5.3 software.

OUTCOME

In this study, National Institute of Health Stroke Scale (NIHSS) score, Modified Rankin Scale (mRS) score scale, symptomatic intracranial hemorrhage (SICH) incidence, All-cause mortality, and so on are used to evaluate the efficacy and safety of tenecteplase thrombolytic therapy in acute ischemic stroke with different doses.

CONCLUSION

This study will provide reliable evidence-based evidence for the clinical application of different doses of tenecteplase in thrombolytic therapy for acute ischemic stroke.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/2MPCW.

Biomimetic nanoparticle technology for cardiovascular disease detection and treatment

Cardiovascular disease (CVD), which encompasses a number of conditions that can affect the heart and blood vessels, presents a major challenge for modern-day healthcare. Nearly one in three people has some form of CVD, with many suffering from multiple or intertwined conditions that can ultimately lead to traumatic events such as a heart attack or stroke. While the knowledge obtained in the past century regarding the cardiovascular system has paved the way for the development of life-prolonging drugs and treatment modalities, CVD remains one of the leading causes of death in developed countries. More recently, researchers have explored the application of nanotechnology to improve upon current clinical paradigms for the management of CVD. Nanoscale delivery systems have many advantages, including the ability to target diseased sites, improve drug bioavailability, and carry various functional payloads. In this review, we cover the different ways in which nanoparticle technology can be applied towards CVD diagnostics and treatments. The development of novel biomimetic platforms with enhanced functionalities is discussed in detail.

Stable cavitation using acoustic phase-change dodecafluoropentane nanoparticles for coronary micro-circulation thrombolysis

BACKGROUND

The thrombolysis in micro-circulation after acute myocardial infarction has been an unsolved issue, as elimination effect of acute thrombolysis and primary intervention were unsatisfied. Stable cavitation using acoustic phase-change nanoparticles may have potential for thrombolysis. Therefore, we sought to investigate a novel treatment method with dodecafluoropentane (DDFP) nanoparticles for rapid and effective thrombolysis in an in-vitro artificial vascular system, as a mimicking preparation of coronary circulation.

METHODS

To simulate thrombus embolism in coronary circulation, an in-vitro artificial vascular system was established with cavitation effect using DDFP nanoparticles. For PBS blank control (group A), SonoVue microbubbles (group B) and DDFP nanoparticles (group C), the durations for cavitation effect were recorded and the thrombolysis efficiency with low intensity focused ultrasound irradiation in the in-vitro vascular system were analyzed with weight loss and pathological changes of thrombus before and after thrombolysis.

RESULTS

The optimal conditions for acoustic cavitation effect were power of 6 W for 20 min by ultrasound irradiation at 37 °C. The weight loss and weight loss rates of thrombus in group C (189.4 ± 30.2 mg and 34.2 ± 5.7%) were higher than those in group A (30.2 ± 16.0 mg and 5.2 ± 2.1%) and group B (84.0 ± 20.4 mg and 14.6 ± 1.5%) (P < 0.01, all). The duration for cavitation effect in group C (32.8 ± 3.9 min) was also longer than those in group A (0.0 ± 0.0 min) and group B (5.3 ± 0.3 min) (P < 0.01, all).

CONCLUSIONS

By stable and sustaining cavitation in targeted area, DDFP nanoparticles with ultrasound irradiation have significantly increased the thrombolysis efficiency, which has provided a powerful experimental foundation for potential coronary thrombolysis.

The application of nanoparticles for neuroprotection in acute ischemic stroke

Stroke still represents one of the most common causes of death and disability worldwide. Acute ischemic stroke (AIS), caused by brain arterial occlusion resulting from a thrombus or embolus, is the most common form of stroke. However, current therapies in AIS are inadequate, and the only US FDA approved treatment is the thrombolytic drug Alteplase. Therefore, establishing effective therapeutic strategies for AIS is urgently needed. Using nanoparticle-based technologies to deliver neuroprotective agents to the ischemic area has attracted increasing attention of late. In this review, the important molecular pathological mechanisms in cerebral ischemia are briefly summarized, the potential of nanoparticulate drug-delivery systems for AIS intervention and recovery are introduced and problems in the medical application of nanoparticles will also be discussed.

Thrombolytic therapy based on fucoidan-functionalized polymer nanoparticles targeting P-selectin

Injection of recombinant tissue plasminogen activator (rt-PA) is the standard drug treatment for thrombolysis. However, rt-PA shows risk of hemorrhages and limited efficiency even at high doses. Polysaccharide-poly(isobutylcyanoacrylate) nanoparticles functionalized with fucoidan and loaded with rt-PA were designed to accumulate on the thrombus. Fucoidan has a nanomolar affinity for the P-selectin expressed by activated platelets in the thrombus. Solid spherical fluorescent nanoparticles with a hydrodynamic diameter of 136 ± 4 nm were synthesized by redox radical emulsion polymerization. The clinical rt-PA formulation was successfully loaded by adsorption on aminated nanoparticles and able to be released in vitro. We validated the in vitro fibrinolytic activity and binding under flow to both recombinant P-selectin and activated platelet aggregates. The thrombolysis efficiency was demonstrated in a mouse model of venous thrombosis by monitoring the platelet density with intravital microscopy. This study supports the hypothesis that fucoidan-nanoparticles improve the rt-PA efficiency. This work establishes the proof-of-concept of fucoidan-based carriers for targeted thrombolysis.

Vinpocetine alleviate cerebral ischemia/reperfusion injury by down-regulating TLR4/MyD88/NF-κB signaling

Inflammatory responses play crucial roles in cerebral ischemia/reperfusion injury. Toll-like receptor 4 (TLR4) is an important mediator of the neuroinflammatory response to cerebral ischemia/reperfusion injury. Vinpocetine is a derivative of the alkaloid vincamine and exerts an anti-inflammatory effect by inhibiting NF-κB activation. However, the effects of vinpocetine on pathways upstream of NF-κB signaling, such as TLR4, have not been fully elucidated. Here, we used mouse middle cerebral artery occlusion (MCAO) and cell-based oxygen-glucose deprivation (OGD) models to evaluate the therapeutic effects and mechanisms of vinpocetine treatment. The vinpocetine treatment significantly reduced mice cerebral infarct volumes and neurological scores. Moreover, the numbers of TUNEL+ and Fluoro-Jade B+ cells were significantly decreased in the ischemic brain tissues after vinpocetine treatment. In the OGD model, the vinpocetine treatment also increased the viability of cultured cortical neurons. Interestingly, vinpocetine exerted a neuroprotective effect on the mouse MCAO model and cell-based OGD model by inhibiting TLR4-mediated inflammatory responses and decreasing proinflammatory cytokine release through the MyD88-dependent signaling pathway, independent of TRIF signaling pathway. In conclusion, vinpocetine exerts anti-inflammatory effects to ameliorate cerebral ischemia/reperfusion injury in vitro and in vivo. Vinpocetine may inhibit inflammatory responses through the TLR4/MyD88/NF-κB signaling pathway, independent of TRIF-mediated inflammatory responses. Thus, vinpocetine may be an attractive therapeutic candidate for the treatment of ischemic cerebral injury or other inflammatory diseases.

Update on Inflammatory Biomarkers and Treatments in Ischemic Stroke

After an acute ischemic stroke (AIS), inflammatory processes are able to concomitantly induce both beneficial and detrimental effects. In this narrative review, we updated evidence on the inflammatory pathways and mediators that are investigated as promising therapeutic targets. We searched for papers on PubMed and MEDLINE up to August 2016. The terms searched alone or in combination were: ischemic stroke, inflammation, oxidative stress, ischemia reperfusion, innate immunity, adaptive immunity, autoimmunity. Inflammation in AIS is characterized by a storm of cytokines, chemokines, and Damage-Associated Molecular Patterns (DAMPs) released by several cells contributing to exacerbate the tissue injury both in the acute and reparative phases. Interestingly, many biomarkers have been studied, but none of these reflected the complexity of systemic immune response. Reperfusion therapies showed a good efficacy in the recovery after an AIS. New therapies appear promising both in pre-clinical and clinical studies, but still need more detailed studies to be translated in the ordinary clinical practice. In spite of clinical progresses, no beneficial long-term interventions targeting inflammation are currently available. Our knowledge about cells, biomarkers, and inflammatory markers is growing and is hoped to better evaluate the impact of new treatments, such as monoclonal antibodies and cell-based therapies.