Nelonemdaz for Patients With Acute Ischemic Stroke Undergoing Endovascular Reperfusion Therapy: A Randomized Phase II Trial

SERP1 Alleviates Cerebral Ischemia/Reperfusion Injury by Inhibiting ER Stress-Mediated Apoptosis

Ischemic stroke is a common disease of the central nervous system, and endoplasmic reticulum (ER) stress-induced apoptosis plays a key role in brain damage following ischemic stroke. Stress-associated endoplasmic reticulum protein 1 (SERP1) is a Sec. 61-associated polypeptide induced by ER stress, which is implicated in stabilizing membrane proteins during ER stress. However, the precise molecular mechanism of SERP1 in ischemic stroke is still unknown. This study aimed to explore the protective effect of SERP1 against cerebral ischemia/reperfusion (I/R) injury. Male Sprague-Dawley rats with transient middle cerebral artery occlusion/reperfusion (tMCAO/R) were used to simulate cerebral I/R injury in vivo. To mimic the cerebral I/R injury in vitro, PC12 cells were treated with oxygen glucose deprivation/reperfusion (OGD/R). The results revealed that the SERP1 expression was increased during cerebral I/R injury in vivo and in vitro. SERP1 knockdown promoted apoptosis and ER stress as well as aggravated I/R-induced brain injury in rats with tMCAO/R, but SERP1 overexpression presented the opposite effects. SERP1 also alleviated OGD/R-induced cell damage in PC12 cells. Mechanically, SERP1 inhibited the ER stress-induced neuronal apoptosis through the PERK-EIF2α-ATF4-CHOP pathway. In conclusion, these results suggest that SERP1 may be a novel candidate gene for therapies against cerebral I/R injury.

Safety and Efficacy of Neuroprotective Agents as Adjunctive Therapies for Reperfusion in the Treatment of Acute Ischemic Stroke: A Systematic Review and Meta-analysis of Randomized Controlled Trials

There is still no clear evidence of the efficacy of the application of neuroprotective agents (NPAs) for acute ischemic stroke (AIS) patients receiving reperfusion therapies. This meta-analysis aimed to determine the effects of NPAs versus placebo on functional and safety outcomes as an adjunctive treatment to intravenous thrombolysis (IVT) or endovascular therapy (EVT) in AIS patients. The primary outcome was neurological functional independence, as evaluated by the proportion of patients whose modified Rankin Scale scores were 0 to 2 at 90 days after treatment. Thirteen randomized controlled trials with a total of 3736 patients were included. The application of NPAs was associated with greater odds of functional independence (odds ratio [OR]: 1.28; 95% CI: 1.12 to 1.46; P < 0.001; I2 = 0.0%) within 90 days. However, subgroup analysis of reperfusion therapy type (IVT, EVT, or both) revealed that only the EVT subgroup showed a significant association between NPAs or placebo and functional independence at 90 days (EVT group, OR: 1.43; 95% CI: 1.05 to 1.94; P = 0.022; I2 = 0.0%; IVT group, OR: 1.51; 95% CI: 0.93 to 2.46; P = 0.099; I2 = 39.8%; IVT plus EVT group, OR: 1.17; 95% CI: 0.94 to 1.45; P = 0.157; I2 = 16.0%). This meta-analysis revealed that NPAs could increase the possibility of AIS patients undergoing reperfusion therapies achieving functional independence within 90 days of onset; however, with the limited number of studies on each drug, further evidence is still needed to demonstrate the efficacy of each individual agent as an adjunctive therapy for different means of reperfusion.

Nelonemdaz Treatment for Patients With Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial

OBJECTIVES

Nelonemdaz is a N-methyl d-aspartate receptor subtype 2B-selective N-methyl-D-aspartate receptor antagonist and a potent free-radical scavenger that might ameliorate hypoxic-ischemic brain injury after out-of-hospital cardiac arrest (OHCA). We investigated the efficacy of nelonemdaz for patients with OHCA.

DESIGN

A double-blind, placebo-controlled, randomized, multicenter phase II trial.

SETTING

This trial enrolled 105 patients at five sites in South Korea between November 18, 2018, and February 23, 2023.

PARTICIPANTS

OHCA patients undergoing targeted temperature management.

INTERVENTIONS

Patients were randomly assigned to high-dose (5250 mg), low-dose (3250 mg), and placebo groups at a 1:1:1 ratio.

MEASUREMENTS AND MAIN RESULTS

Patients with a median age of 61 years (82% male) were assigned to the high-dose (n = 37), low-dose (n = 35), and placebo (n = 33) groups. The primary outcome, the serum level of neuron-specific enolase (NSE) at 48-52 hours, was evaluated in 93 patients. There was no difference in serum NSE between high-dose (median and interquartile range; 23.7, 15.0-69.9) and placebo (17.5, 13.6-113.0) groups, or between low-dose (26.6, 16.2-83.4) and placebo groups (all p > 0.05). Brain MRI fractional anisotropy was significantly higher in the high-dose group compared with the placebo group (0.465, 0.449-0.485 vs. 0.441, 0.431-0.464; p = 0.028), but not between low-dose (0.462, 0.439-0.480) and placebo groups (p > 0.05). At day 90, the common odds ratio (95% CI) indicating a numerically favorable shift in the modified Rankin Scale was 1.25 (0.48-3.24) and 1.22 (0.47-3.20) in the high-dose and low-dose groups, respectively, compared with placebo group (all p > 0.05). No serious adverse events were reported.

CONCLUSIONS

Nelonemdaz treatment of patients after OHCA did not reduce serum NSE levels compared with controls. Patients treated with high-dose nelonemdaz showed higher brain MRI fractional anisotropy suggesting less cerebral white matter damage.

The mitochondria as a potential therapeutic target in cerebral I/R injury

Ischemic stroke is a major cause of mortality and disability worldwide. Among patients with ischemic stroke, the primary treatment goal is to reduce acute cerebral ischemic injury and limit the infarct size in a timely manner by ensuring effective cerebral reperfusion through the administration of either intravenous thrombolysis or endovascular therapy. However, reperfusion can induce neuronal death, known as cerebral reperfusion injury, for which effective therapies are lacking. Accumulating data supports a paradigm whereby cerebral ischemia/reperfusion (I/R) injury is coupled with impaired mitochondrial function, contributing to the pathogenesis of ischemic stroke. Herein, we review recent evidence demonstrating a heterogeneous mitochondrial response following cerebral I/R injury, placing a specific focus on mitochondrial protein modifications, reactive oxygen species, calcium (Ca2+), inflammation, and quality control under experimental conditions using animal models.

Nelonemdaz and Patients With Acute Ischemic Stroke and Mechanical Reperfusion: The RODIN Randomized Clinical Trial

Importance

Nelonemdaz selectively antagonizes the 2B subunit of the N-methyl-d-aspartate glutamate receptor and scavenges free radical species.

Objective

To evaluate whether nelonemdaz enhances the clinical outcomes of patients with acute ischemic stroke undergoing emergent reperfusion therapy.

Design, Setting, and Participants

This multicenter double-blind placebo-controlled randomized phase 3 trial (December 25, 2021, to June 30, 2023, in South Korea) recruited patients with acute ischemic stroke who met the following criteria: National Institutes of Health Stroke Scale score greater than or equal to 8, Alberta Stroke Program Early Computed Tomography score greater than or equal to 4, and endovascular thrombectomy within 12 hours after stroke onset.

Intervention

Patients were assigned in a 1:1 ratio to receive intravenous infusions of nelonemdaz twice a day for 5 days or a matching placebo.

Main Outcomes and Measures

The primary end point was a favorable shift in the modified Rankin scale (mRS) 12 weeks after stroke onset. The secondary end points included various composites of the mRS at 5 and 12 weeks, symptomatic intracranial hemorrhage, and infarct volume. Both intention-to-treat and per-protocol analyses were conducted.

Results

A total of 496 patients were enrolled across 24 Korean stroke centers, of whom 39 dropped out (254 men [55.6%]; mean [SD] age, 72.9 [12.1] years). Baseline characteristics of study participants did not significantly differ. For the primary end point, the distribution of the mRS scores at 12 weeks did not significantly differ between the nelonemdaz and placebo groups (common odds ratio, 0.95; 95% CI, 0.69-1.31). For the secondary end points, a median of mRS at 5 weeks (3 vs 3) and mRS 0 at 12 weeks (18.1% vs 18.2%) did not differ substantially between groups. The occurrence of symptomatic intracranial hemorrhage (2.7% vs 0.9%) and infarct volume within 24 hours of the last trial drug infusion (42 vs 38 mL) did not differ significantly between groups. No serious adverse events were reported regarding the trial drug and placebo.

Conclusions and Relevance

In this randomized clinical trial, nelonemdaz did not meet the primary efficacy end point compared with placebo.

Trial Registration

ClinicalTrials.gov Identifier: NCT05041010.

The Therapeutic Effects of SP-8356, a Verbenone Derivative, with Multimodal Cytoprotective Mechanisms in an Ischemic Stroke Rat Model

An ischemic cerebral stroke results from the interruption of blood flow to the brain, triggering rapid and complex cascades of excitotoxicity, oxidative stress, and inflammation. Current reperfusion therapies, including intravenous thrombolysis and mechanical thrombectomy, cause further brain injury due to reperfusion-induced cytotoxicity. To date, novel cytoprotective therapies that could address these challenges have yet to be developed, likely due to the limitations of targeting a single pathologic mechanism. To address these unmet clinical needs, we investigated a synthetic verbenone derivative, SP-8356, as a potential multi-target cytoprotective agent for acute ischemic strokes. In transient middle cerebral artery occlusion (MCAO) rats, SP-8356 significantly reduced brain infarct and edema volumes while improving acute neurological deficits in a dose-dependent manner. Furthermore, SP-8356 improved long-term outcomes, particularly by reducing mortality. These potent cytoprotective effects of SP-8356 were achieved by suppressing the excessive production of free radicals and pro-inflammatory cytokines, reducing the infiltration of inflammatory cells, and mitigating increases in blood-brain barrier permeability. Additional research is needed to determine whether co-administration of SP-8356 can extend the therapeutic time window of reperfusion therapies by mitigating ischemia/reperfusion injury.

Modulation of Ca2+ oscillation following ischemia and nicotinic acetylcholine receptors in primary cortical neurons by high-throughput analysis

Calcium oscillations in primary neuronal cultures and iPSCs have been employed to investigate arrhythmogenicity and epileptogenicity in drug development. Previous studies have demonstrated that Ca2+ influx via NMDA and nicotinic acetylcholine receptors (nAChRs) modulates Ca2+ oscillations. Nevertheless, there has been no comprehensive investigation into the impact of ischemia or nAChR-positive allosteric modulators (PAM) drugs on Ca2+ oscillations at a level that would facilitate high-throughput screening. We investigated the effects of ischemia and nAChR subtypes or nAChR PAM agonists on Ca2+ oscillations in high-density 2D and 3D-sphere primary neuronal cultures using 384-well plates with FDSS-7000. Ischemia for 1 and 2 h resulted in an increase in the frequency of Ca2+ oscillations and a decrease in their amplitude in a time-dependent manner. The NMDA and AMPA receptor inhibition significantly suppressed Ca2+ oscillation. Inhibition of NR2A or NR2B had the opposite effect on Ca oscillations. The potentiation of ischemia-induced Ca2+ oscillations was significantly inhibited by the NMDA receptor antagonist, MK-801, and the frequency of these oscillations was suppressed by the NR2B inhibitor, Ro-256981. In the 3D-neurosphere, the application of an α7nAChR agonist increased the frequency of Ca2+ oscillations, whereas the activation of α4β2 had no effect. The combination of nicotine and PNU-120596 (type II PAM) affected the frequency and amplitude of Ca2+ oscillations in a manner distinct from that of type I PAM. These systems may be useful not only for detecting epileptogenicity but also in the search for neuroprotective agents against cerebral ischemia.

HACE1 exerts a neuroprotective role against oxidative stress in cerebral ischemia-reperfusion injury by activating the PI3K/AKT/Nrf2 pathway

HECT domain and Ankyrin repeat-containing E3 ubiquitin protein ligase 1 (HACE1) is an E3 ubiquitin ligase involving oxidative stress, an important contributor in cerebral ischemia-reperfusion injury (CIRI). It was proposed to be associated with the PI3K/AKT pathway and Nrf2 nuclear translocation, which are important players of oxidative stress. Therefore, we supposed that HACE1 might affect CIRI by regulating the PI3K/AKT/Nrf2 pathway. Here, we used the transient middle cerebral artery occlusion-reperfusion (tMCAO/R) model to induce CIRI in rats and found lower HACE1 expression in ischemic rats compared with the control. To explore the exact role of HACE1, the lentivirus vector carrying the HACE1 sequence was administrated to rats by intracerebroventricular injection (1 × 109 TU/mL, 9 μL) one week before tMCAO/R operation. HACE1 overexpression alleviated tMCAO/R-induced brain damage in rats. Further studies revealed that it reduced oxidative stress via activating the PI3K/AKT/Nrf2 pathway, thereby inhibiting neuronal apoptosis in the ischemic penumbra of rats with CIRI. Then, differentiated PC12 cells were cultured in oxygen-glucose deprivation-reoxygenation (OGD/R) conditions (OGD: 1 % O2, 94 % N2, and 5 % CO2; R: normal atmosphere) to simulate CIRI in vitro. Similarly, HACE1 overexpression inhibited neuronal apoptosis caused by OGD/R treatment. The PI3K inhibitor LY294002 reversed the inhibitory effects of HACE1 overexpression on oxidative stress in OGD/R-injured cells, accompanied by the inactivated AKT/Nrf2 pathway. Altogether, our results suggest that HACE1 protects against oxidative stress-induced neuronal apoptosis in CIRI by activating the PI3K/AKT/Nrf2 pathway, providing a new insight into the CIRI treatment.

Reperfusion and cytoprotective agents are a mutually beneficial pair in ischaemic stroke therapy: an overview of pathophysiology, pharmacological targets and candidate drugs focusing on excitotoxicity and free radical

Stroke is the second-leading cause of death and the leading cause of disability in much of the world. In particular, China faces the greatest challenge from stroke, since the population is aged quickly. In decades of clinical trials, no neuroprotectant has had reproducible efficacy on primary clinical end points, because reperfusion is probably a necessity for neuroprotection to be clinically beneficial. Fortunately, the success of thrombolysis and endovascular thrombectomy has taken us into a reperfusion era of acute ischaemic stroke (AIS) therapy. Brain cytoprotective agents can prevent detrimental effects of ischaemia, and therefore 'freeze' ischaemic penumbra before reperfusion, extend the time window for reperfusion therapy. Because reperfusion often leads to reperfusion injury, including haemorrhagic transformation, brain oedema, infarct progression and neurological worsening, cytoprotective agents will enhance the efficacy and safety of reperfusion therapy by preventing or reducing reperfusion injuries. Therefore, reperfusion and cytoprotective agents are a mutually beneficial pair in AIS therapy. In this review, we outline critical pathophysiological events causing cell death within the penumbra after ischaemia or ischaemia/reperfusion in the acute phase of AIS, focusing on excitotoxicity and free radicals. We discuss key pharmacological targets for cytoprotective therapy and evaluate the recent advances of cytoprotective agents going through clinical trials, highlighting multitarget cytoprotective agents that intervene at multiple levels of the ischaemic and reperfusion cascade.

Targeting NMDA receptors with an antagonist is a promising therapeutic strategy for treating neurological disorders

Glutamate activates the NMDARs, significantly affecting multiple processes such as learning, memory, synaptic integration, and excitatory transmission in the central nervous system. Uncontrolled activation of NMDARs is a significant contributor to synaptic dysfunction. Having a properly functioning NMDAR and synapse is crucial for maintaining neuronal communication. In addition, the dysfunction of NMDAR and synapse function could contribute to the development of neurological disorders at the neuronal level; hence, targeting NMDARs with antagonists in the fight against neurological disorders is a promising route. Recently published results from the animal study on different kinds of brain diseases like stroke, epilepsy, tinnitus, ataxia, Alzheimer's disease, Parkinson's disease, and spinal cord injury have demonstrated promising therapeutic scopes. Several NMDA receptor antagonists, such as memantine, MK801, ketamine, ifenprodil, gacyclidine, amantadine, agmatine, etc., showed encouraging results against different brain disease mouse models. Given the unique expression of different subunits of the well-organized NMDA receptor system by neurons. It could potentially lead to the development of medications specifically targeting certain receptor subtypes. For a future researcher, conducting more targeted research and trials is crucial to fully understand and develop highly specific medications with good clinical effects and potential neuroprotective properties.

Targeted pathophysiological treatment of ischemic stroke using nanoparticle-based drug delivery system

Ischemic stroke poses significant challenges in terms of mortality and disability rates globally. A key obstacle to the successful treatment of ischemic stroke lies in the limited efficacy of administering therapeutic agents. Leveraging the unique properties of nanoparticles for brain targeting and crossing the blood-brain barrier, researchers have engineered diverse nanoparticle-based drug delivery systems to improve the therapeutic outcomes of ischemic stroke. This review provides a concise overview of the pathophysiological mechanisms implicated in ischemic stroke, encompassing oxidative stress, glutamate excitotoxicity, neuroinflammation, and cell death, to elucidate potential targets for nanoparticle-based drug delivery systems. Furthermore, the review outlines the classification of nanoparticle-based drug delivery systems according to these distinct physiological processes. This categorization aids in identifying the attributes and commonalities of nanoparticles that target specific pathophysiological pathways in ischemic stroke, thereby facilitating the advancement of nanomedicine development. The review discusses the potential benefits and existing challenges associated with employing nanoparticles in the treatment of ischemic stroke, offering new perspectives on designing efficacious nanoparticles to enhance ischemic stroke treatment outcomes.

Mechanisms of Postischemic Stroke Angiogenesis: A Multifaceted Approach

Ischemic stroke constitutes a significant global health care challenge, and a comprehensive understanding of its recovery mechanisms is imperative for the development of innovative therapeutic strategies. Angiogenesis, a pivotal element of ischemic tissue repair, facilitates the restoration of blood flow to damaged regions, thereby promoting neuronal regeneration and functional recovery. Nevertheless, the mechanisms underlying postischemic stroke angiogenesis remain incompletely elucidated. This review meticulously examines the constituents of the neurovascular unit, ion channels, molecular mediators, and signaling pathways implicated in angiogenesis following stroke. Furthermore, it delves into prospective therapeutic strategies informed by these factors. Our objective is to provide detailed and exhaustive information on the intricate mechanisms governing postischemic stroke angiogenesis, thus providing a robust scientific foundation for the advancement of novel neurorepair therapies.

Neuroprotection during Thrombectomy for Acute Ischemic Stroke: A Review of Future Therapies

Stroke is a major cause of death and disability worldwide. Endovascular thrombectomy has been impactful in decreasing mortality. However, many clinical results continue to show suboptimal functional outcomes despite high recanalization rates. This gap in recanalization and symptomatic improvement suggests a need for adjunctive therapies in post-thrombectomy care. With greater insight into ischemia-reperfusion injury, recent preclinical testing of neuroprotective agents has shifted towards preventing oxidative stress through upregulation of antioxidants and downstream effectors, with positive results. Advances in multiple neuroprotective therapies, including uric acid, activated protein C, nerinetide, otaplimastat, imatinib, verapamil, butylphthalide, edaravone, nelonemdaz, ApTOLL, regional hypothermia, remote ischemic conditioning, normobaric oxygen, and especially nuclear factor erythroid 2-related factor 2, have promising evidence for improving stroke care. Sedation and blood pressure management in endovascular thrombectomy also play crucial roles in improved stroke outcomes. A hand-in-hand approach with both endovascular therapy and neuroprotection may be the key to targeting disability due to stroke.

[Neurocytoprotection advances in reperfusion therapy]

Acute stroke is the second leading cause of death and the third leading cause of disability in the world. Ischemic stroke (IS) the most common type of stroke. In acute cerebral ischemia, damage to the brain tissue is complex and includes blood-brain barrier (BBB) dysfunction, neuroinflammation, oxidative stress, activation of intracellular and extracellular signaling pathways, expression of neurotoxic agents, excitotoxicity, and apoptosis. In acute IS, reperfusion therapy (RT), is one of the most prominent treatment options. Most of the randomized clinical trials demonstrated the efficacy and safety of RT. The use of novel neuroimaging techniques (CT-perfusion and new MRI modalities) significantly expanded the RT selection criteria in patients with IS. One of the possible ways to further expand the RT is to combine it with neurocytoprotection. According to many researchers, this could potentially significantly improve the efficacy and safety of RT. This opinion is based on the concept of preserving brain tissue in the ischemic penumbra region. The aim of this review was to analyze the current trials of neurocytoprotection in combination with RT in IS patients.

Risk Factors, Pathophysiologic Mechanisms, and Potential Treatment Strategies of Futile Recanalization after Endovascular Therapy in Acute Ischemic Stroke

Endovascular therapy is the first-line treatment for acute ischemic stroke. However, studies have shown that, even with the timely opening of occluded blood vessels, nearly half of all patients treated with endovascular therapy for acute ischemic stroke still have poor functional recovery, a phenomenon called "futile recanalization.". The pathophysiology of futile recanalization is complex and may include tissue no-reflow (microcirculation reperfusion failure despite recanalization of the occluded large artery), early arterial reocclusion (reocclusion of the recanalized artery 24-48 hours post endovascular therapy), poor collateral circulation, hemorrhagic transformation (cerebral bleeding following primary ischemic stroke), impaired cerebrovascular autoregulation, and large hypoperfusion volume. Therapeutic strategies targeting these mechanisms have been attempted in preclinical research; however, translation to the bedside remains to be explored. This review summarizes the risk factors, pathophysiological mechanisms, and targeted therapy strategies of futile recanalization, focusing on the mechanisms and targeted therapy strategies of no-reflow to deepen the understanding of this phenomenon and provide new translational research ideas and potential intervention targets for improving the efficacy of endovascular therapy for acute ischemic stroke.

Evolving Clinical-Translational Investigations of Cerebroprotection in Ischemic Stroke

Ischemic stroke is a highly morbid disease, with over 50% of large vessel stroke (middle cerebral artery or internal carotid artery terminus occlusion) patients suffering disability despite maximal acute reperfusion therapy with thrombolysis and thrombectomy. The discovery of the ischemic penumbra in the 1980s laid the foundation for a salvageable territory in ischemic stroke. Since then, the concept of neuroprotection has been a focus of post-stroke care to (1) minimize the conversion from penumbra to core irreversible infarct, (2) limit secondary damage from ischemia-reperfusion injury, inflammation, and excitotoxicity and (3) to encourage tissue repair. However, despite multiple studies, the preclinical-clinical research enterprise has not yet created an agent that mitigates post-stroke outcomes beyond thrombolysis and mechanical clot retrieval. These translational gaps have not deterred the scientific community as agents are under continuous investigation. The NIH has recently promoted the concept of cerebroprotection to consider the whole brain post-stroke rather than just the neurons. This review will briefly outline the translational science of past, current, and emerging breakthroughs in cerebroprotection and use of these foundational ideas to develop a novel paradigm for optimizing stroke outcomes.

Combined Therapeutics: Future Opportunities for Co-therapy with Thrombectomy

Stroke is an urgent public health issue with millions of patients worldwide living with its devastating effects. The advent of thrombolysis and endovascular thrombectomy has transformed the hyperacute care of these patients. However, a significant proportion of patients receiving these therapies still goes on to have unfavorable outcomes and many more remain ineligible for these therapies based on our current guidelines. The future of stroke care will depend on an expansion of the scope of thrombolysis and endovascular thrombectomy to patients outside traditional time windows, more distal occlusions, and large vessel occlusions with mild clinical deficits, for whom clinical trial results have not proven therapeutic efficacy. Novel cytoprotective therapies targeting the ischemic cascade and reperfusion injury therapy, in combination with our existing treatment modalities, should be explored to further improve outcomes for these patients with acute ischemic stroke. In this review, we will review the current status of thrombolysis and thrombectomy, suggest additional data that is needed to enhance these therapies, and discuss how cytoprotection might be combined with thrombectomy.

Clinically Ineffective Reperfusion After Endovascular Therapy in Acute Ischemic Stroke

Endovascular treatment is a highly effective therapy for acute ischemic stroke due to large vessel occlusion. However, in clinical practice, nearly half of the patients do not have favorable outcomes despite successful recanalization of the occluded artery. This unfavorable outcome can be defined as having clinically ineffective reperfusion. The objective of the review is to describe clinically ineffective reperfusion after endovascular therapy and its underlying risk factors and mechanisms, including initial tissue damage, cerebral edema, the no-reflow phenomenon, reperfusion injury, procedural features, and variations in postprocedural management. Further research is needed to more accurately identify patients at a high risk of clinically ineffective reperfusion after endovascular therapy and to improve individualized periprocedural management strategies, to increase the chance of achieving favorable clinical outcomes.

Neuroprotective Strategies for Ischemic Stroke-Future Perspectives

Ischemic stroke is the main cause of death and the most common cause of acquired physical disability worldwide. Recent demographic changes increase the relevance of stroke and its sequelae. The acute treatment for stroke is restricted to causative recanalization and restoration of cerebral blood flow, including both intravenous thrombolysis and mechanical thrombectomy. Still, only a limited number of patients are eligible for these time-sensitive treatments. Hence, new neuroprotective approaches are urgently needed. Neuroprotection is thus defined as an intervention resulting in the preservation, recovery, and/or regeneration of the nervous system by interfering with the ischemic-triggered stroke cascade. Despite numerous preclinical studies generating promising data for several neuroprotective agents, successful bench-to-bedside translations are still lacking. The present study provides an overview of current approaches in the research field of neuroprotective stroke treatment. Aside from "traditional" neuroprotective drugs focusing on inflammation, cell death, and excitotoxicity, stem-cell-based treatment methods are also considered. Furthermore, an overview of a prospective neuroprotective method using extracellular vesicles that are secreted from various stem cell sources, including neural stem cells and bone marrow stem cells, is also given. The review concludes with a short discussion on the microbiota-gut-brain axis that may serve as a potential target for future neuroprotective therapies.

The Rescue on Reperfusion Damage in Cerebral Infarction by Nelonemdaz (RODIN) Trial: Protocol for a Double-Blinded Clinical Trial of Nelonemdaz in Patients with Hyperacute Ischemic Stroke and Endovascular Thrombectomy

BACKGROUND AND PURPOSE

Nelonemdaz (Neu2000) has both selective antagonism against 2B subunit of N-methyl-D-aspartate receptor and antioxidant activity. This drug provides sufficient evidence of neuroprotection in acute cerebral ischemia/reperfusion models. This phase III trial aims to determine this effect in patients.

DESIGN

The Rescue on Reperfusion Damage in Cerebral Infarction by Nelonemdaz is a multicenter, double-blinded clinical trial. A total of 496 patients will be randomly assigned into the nelonemdaz (a total of 5,250 mg divided by 10 times for 5 days) and placebo groups. Patients will be included if they have an acute ischemic stroke (National Institutes of Health Stroke Scale score ≥8) caused by intracranial large vessel occlusion in the anterior circulation (Alberta Stroke Program Early CT Score ≥4), and if they are expected to undergo endovascular thrombectomy within 12 hours after stroke onset.

ENDPOINTS

The primary endpoint is a favorable shift in the modified Rankin Scale (mRS) score at 90 days after the first dose of drug. The data will be analyzed by the Cochran-Mantel-Haenszel shift test. The secondary endpoints include functional independence (mRS 0-2) at 35 and 90 days, the favorable shift of mRS at 35 days, the proportion of mRS 0 at 35 and 90 days, and the occurrence rates of symptomatic intracranial hemorrhage within 7 days.

CONCLUSION

This trial will clarify the efficacy and safety of nelonemdaz in patients with acute ischemic stroke and endovascular thrombectomy. This study has been registered at ClinicalTrials. gov (NCT05041010).