Edaravone Acute Infarction Study Group. Effect of a novel free radical scavenger, edaravone (MCI-186), on acute brain infarction. Randomized, placebo-controlled, double-blind study at multicenters

The role of oxidative stress in blood-brain barrier disruption during ischemic stroke: Antioxidants in clinical trials

Ischemic stroke is one of the leading causes of death and disability. Occlusion and reperfusion of cerebral blood vessels (i.e., ischemia/reperfusion (I/R) injury) generates reactive oxygen species (ROS) that contribute to brain cell death and dysfunction of the blood-brain barrier (BBB) via oxidative stress. BBB disruption influences the pathogenesis of ischemic stroke by contributing to cerebral edema, hemorrhagic transformation, and extravasation of circulating neurotoxic proteins. An improved understanding of mechanisms for ROS-associated alterations in BBB function during ischemia/reperfusion (I/R) injury can lead to improved treatment paradigms for ischemic stroke. Unfortunately, progress in developing ROS targeted therapeutics that are effective for stroke treatment has been slow. Here, we review how ROS are produced in response to I/R injury, their effects on BBB integrity (i.e., tight junction protein complexes, transporters), and the utilization of antioxidant treatments in ischemic stroke clinical trials. Overall, knowledge in this area provides a strong translational framework for discovery of novel drugs for stroke and/or improved strategies to mitigate I/R injury in stroke patients.

CircRNA: A new target for ischemic stroke

Ischemic stroke, a clinical emergency and disease with a poor prognosis, has a negative impact on the survival index of patients. It is frequently precipitated by a multitude of risk factors, including trauma. Currently, there is a paucity of predictive indicators for early intervention. As stable and abundant RNA in the body, circRNAs play a regulatory role in miRNAs and proteins, which affect the occurrence and development of diseases. Moreover, circRNAs can serve as predictors of clinical diseases. Several studies have demonstrated that circRNAs play pivotal roles in numerous aspects of ischemic stroke. Consequently, circRNAs have emerged as key areas of investigation in the field of ischemic stroke.

The Influence of Oxidative Stress Markers in Patients with Ischemic Stroke

Stroke is the second leading cause of death worldwide, and its incidence is rising rapidly. Acute ischemic stroke is a subtype of stroke that accounts for the majority of stroke cases and has a high mortality rate. An effective treatment for stroke is to minimize damage to the brain's neural tissue by restoring blood flow to decreased perfusion areas of the brain. Many reports have concluded that both oxidative stress and excitotoxicity are the main pathological processes associated with ischemic stroke. Current measures to protect the brain against serious damage caused by stroke are insufficient. For this reason, it is important to investigate oxidative and antioxidant strategies to reduce oxidative damage. This review focuses on studies assessing the concentration of oxidative stress biomarkers and the level of antioxidants (enzymatic and non-enzymatic) and their impact on the clinical prognosis of patients after stroke. Mechanisms related to the production of ROS/RNS and the role of oxidative stress in the pathogenesis of ischemic stroke are presented, as well as new therapeutic strategies aimed at reducing the effects of ischemia and reperfusion.

Meldonium, as a potential neuroprotective agent, promotes neuronal survival by protecting mitochondria in cerebral ischemia-reperfusion injury

BACKGROUND

Stroke is a globally dangerous disease capable of causing irreversible neuronal damage with limited therapeutic options. Meldonium, an inhibitor of carnitine-dependent metabolism, is considered an anti-ischemic drug. However, the mechanisms through which meldonium improves ischemic injury and its potential to protect neurons remain largely unknown.

METHODS

A rat model with middle cerebral artery occlusion (MCAO) was used to investigate meldonium's neuroprotective efficacy in vivo. Infarct volume, neurological deficit score, histopathology, neuronal apoptosis, motor function, morphological alteration and antioxidant capacity were explored via 2,3,5-Triphenyltetrazolium chloride staining, Longa scoring method, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay, rotarod test, transmission electron microscopy and Oxidative stress index related kit. A primary rat hippocampal neuron model subjected to oxygen-glucose deprivation reperfusion was used to study meldonium's protective ability in vitro. Neuronal viability, mitochondrial membrane potential, mitochondrial morphology, respiratory function, ATP production, and its potential mechanism were assayed by MTT cell proliferation and cytotoxicity assay kit, cell-permeant MitoTracker® probes, mitochondrial stress, real-time ATP rate and western blotting.

RESULTS

Meldonium markedly reduced the infarct size, improved neurological function and motor ability, and inhibited neuronal apoptosis in vivo. Meldonium enhanced the morphology, antioxidant capacity, and ATP production of mitochondria and inhibited the opening of the mitochondrial permeability transition pore in the cerebral cortex and hippocampus during cerebral ischemia-reperfusion injury (CIRI) in rats. Additionally, meldonium improved the damaged fusion process and respiratory function of neuronal mitochondria in vitro. Further investigation revealed that meldonium activated the Akt/GSK-3β signaling pathway to inhibit mitochondria-dependent neuronal apoptosis.

CONCLUSION

Our study demonstrated that meldonium shows a neuroprotective function during CIRI by preserving the mitochondrial function, thus prevented neurons from apoptosis.

Recent developments in the design of functional derivatives of edaravone and exploration of their antioxidant activities

Edaravone, a pyrazalone derivative, is an antioxidant and free radical scavenger used to treat oxidative stress-related diseases. It is a proven drug to mitigate conditions prevailing to oxidative stress by inhibiting lipid peroxidation, reducing inflammation, and thereby preventing endothelial cell death. In recent years, considerable interest has been given by researchers in the derivatization of edaravone by adding varieties of substituents of versatile steric and functional properties to improve its antioxidant and pharmacological activity. This review accounts all the important methods developed for the derivatization of edaravone and the impacts of the structural modifications on the antioxidant activity of the motif.

HH-A, a modified honokiol, protects against cerebral ischemia/reperfusion induced brain injury in rodent via Nrf2/HO-1 signaling pathways

Honokiol, a bioactive component found in Magnolia officinalis, has shown in protecting against ischemic stroke in animal models. However, its poor water solubility has limited its clinical applications. In this study, we introduced a hydrophilic building block on the aromatic ring of honokiol, resulting in the synthesis of four new compounds (HH-A, -B, -C and -D) with significantly improved water solubility. We then investigated the neuroprotective effects of these compounds in mouse and rat models of transient middle cerebral artery occlusion/reperfusion (tMCAO/R) brain injury. Among the compounds tested, HH-A, also known as (S)-6-((3',5-diallyl-2,4'-dihydroxy-[1,1'-biphenyl]-3-yl)amino)-6-oxohexane-1,5-diaminium chloride, showed the most promising results. HH-A was found to significantly reduced the infarct volume and brain edema in mice. It also outperformed the other three compounds and honokiol, even surpassing the effects of edaravone dexborneol. Additionally, HH-A demonstrated dose-dependent improvements in body weight, neurological deficits, and infarct volume. Further analysis in tMCAO/R rat model revealed that HH-A treatment led to significant upregulations of Nrf2 and HO-1 in the brain. HH-A also significantly reduced the expression of HNE, and exhibited anti-apoptotic effects by decreasing the expression of Bax and increasing the expression of Bcl-2. This was further supported by a decrease in the number of TUNEL positive cells. Taken together, the neuroprotective effects of HH-A may be attributed to its ability to target the Nrf2/HO-1 signaling pathway, leading to reduced oxidative stress and apoptosis in the brain. These findings suggest that HH-A has potential as a therapeutic agent for the treatment of ischemic stroke.

Stent Retriever Angioplasty for Acute Restenosis of the Middle Cerebral Artery: A Case Report

We present a case of ischemic stroke treated by stent retriever angioplasty for restenosis during mechanical thrombectomy. An 85-year-old man was admitted to our hospital because of left hemiplegia and left-sided hemispatial neglect caused by an occlusion at the origin of the right middle cerebral artery. Although mechanical thrombectomy transiently resulted in recanalization of the occluded lesion, restenosis immediately occurred and recurred repeatedly. On an angiogram, the stent retriever appeared poorly dilated at the stenosis and showed a contrast deficit. We concluded that restenosis was due to a secondary thrombus resulting from a ruptured atherosclerotic plaque. The stent retriever was kept deployed for 15 minutes. After the stent was retrieved, restenosis did not occur. Stent retriever angioplasty may be effective for determining the cause of restenosis after mechanical thrombectomy as well as for the treatment of restenosis.

Edaravone Dexborneol mitigates pathology in animal and cell culture models of Alzheimer's disease by inhibiting neuroinflammation and neuronal necroptosis

BACKGROUND

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease with limited disease-modifying treatments. Drug repositioning strategy has now emerged as a promising approach for anti-AD drug discovery. Using 5×FAD mice and Aβ-treated neurons in culture, we tested the efficacy of Y-2, a compounded drug containing the antioxidant Edaravone (Eda), a pyrazolone and (+)-Borneol, an anti-inflammatory diterpenoid from cinnamon, approved for use in amyotrophic lateral sclerosis patients.

RESULTS

We examined effects of Y-2 versus Eda alone by i.p. administered in 8-week-old 5×FAD mice (females) for 4 months by comparing cognitive function, Aβ pathologies, neuronal necroptosis and neuroinflammation. Using primary neurons and astrocytes, as well as neuronal and astrocytic cell lines, we elucidated the molecular mechanisms of Y-2 by examining neuronal injury, astrocyte-mediated inflammation and necroptosis. Here, we find that Y-2 improves cognitive function in AD mice. Histopathological data show that Y-2, better than Eda alone, markedly ameliorates Aβ pathologies including Aβ burden, astrogliosis/microgliosis, and Tau phosphorylation. In addition, Y-2 reduces Aβ-induced neuronal injury including neurite damage, mitochondrial impairment, reactive oxygen species production and NAD+ depletion. Notably, Y-2 inhibits astrocyte-mediated neuroinflammation and attenuates TNF-α-triggered neuronal necroptosis in cell cultures and AD mice. RNA-seq further demonstrates that Y-2, compared to Eda, indeed upregulates anti-inflammation pathways in astrocytes.

CONCLUSIONS

Our findings infer that Y-2, better than Eda alone, mitigates AD pathology and may provide a potential drug candidate for AD treatment.

Ginkgolide injections in meglumine, combined with edaravone, significantly increases the efficacy in acute ischemic stroke: A meta-analysis

Objective

This study aimed to evaluate the efficacy of combining diterpene ginkgolide meglumine injection (DGMI) with edaravone for the treatment of acute ischemic stroke. This is particularly relevant because Western drugs, excluding intravenous thrombolysis, have shown limited success.

Methods

A comprehensive search was conducted using multiple databases, including PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure WanFang, VIP, and Chinese Biomedical Database (CBM) until June 2023. The data were analyzed using fixed-effects and random-effects models in Review Manager. The mean difference with 95% confidence interval was calculated for each outcome.

Results

Eighteen studies involving 1,636 participants were included in the analysis. The DGMI group showed significant reductions in the National Institutes of Health Stroke Scale (NIHSS) score, modified Rankin Scale (mRS) score, and C-reactive protein (CRP) level, compared to the control group. Furthermore, the DGMI group showed a significant improvement in superoxide dismutase (SOD) levels and a reduction in malondialdehyde (MDA) levels. The combination of DGMI and edaravone was more effective in reducing neuron-specific enolase (NSE) levels following brain tissue injury than edaravone alone. Additionally, DGMI complemented edaravone in reducing rheological parameters associated with ischemic stroke, including hematocrit, plasma viscosity, platelet adhesion rate, and erythrocyte deformation index.

Conclusion

The combination of DGMI and edaravone significantly improved the therapeutic efficacy in patients with acute ischemic stroke. However, more extensive and high-quality clinical trials are required to validate these underlying mechanisms.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=260215, identifier: PROSPERO (CRD42021260215).

Efficacy and safety of short-term edaravone or nerve growth factor add-on therapy for alcohol-related brain damage: A multi-centre randomised control trial

AIMS

To measure the therapeutic effect of an anti-oxidant, edaravone (EDV), or neurotrophic treatment with nerve growth factor (NGF) as an add-on treatment for alcohol-related brain damage (ARBD).

DESIGN

Multi-centre, randomised, single-blinded, comparative clinical trial.

SETTING AND PARTICIPANTS

One hundred and twenty-two inpatients recruited from seven hospitals in different regions of China, all diagnosed with ARBD and aged 18 to 65 years old; among them, only two were female.

INTERVENTION AND COMPARATOR

Patients were randomly assigned to receive one of three treatments for 2 weeks: 40 patients, treatment as usual (TAU: a combination of intramuscular injections of thiamine, intravenous infusions of other B vitamins with vitamin C and oral medication with vitamin E per day); 40, EDV add-on treatment to TAU (intravenous infusion with 30 mg of EDV twice per day); and 42, NGF add-on treatment to TAU (intramuscular injection of 20 μg of NGF per day). The patients underwent follow-up for 24 weeks.

MEASUREMENTS

The primary outcome was the composite score of executive cognitive function in the 2nd week after treatment, which was measured as the mean of the Z scores of the assessments, including the digit symbol substitute test (DSST), digit span memory test-forward (DST-F), digit span memory test-reverse (DST-R) and space span memory test (SSMT). The secondary outcomes were the composite scores at later follow-ups, the score for each component of cognitive function, global cognitive function measured by the Montreal Cognitive Assessment (MoCA), craving for alcohol and the safety of the therapies.

FINDINGS

EDV add-on treatment improved the composite score of executive cognitive function better than TAU in the 2nd week (adjusted mean difference: 0.24, 95% confidence interval 0.06 to 0.41; P = 0.008), but NGF add-on treatment did not (adjusted mean difference: 0.07, 95% confidence interval -0.09 to 0.24; P = 0.502). During the follow-up to 24 weeks, EDV add-on treatment improved the composite score of executive cognitive function and DST-R score better than TAU (both P < 0.01). Craving for alcohol was relieved in all three groups. No severe adverse events were observed.

CONCLUSION

The short-term addition of edaravone to supplementary therapy treatment for alcohol-related brain damage (ARBD) improved executive cognitive function in patients with ARBD.

The Potential of Twendee X® as a Safe Antioxidant Treatment for Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune disease characterized by systemic skin hardening, which combines Raynaud's phenomenon and other vascular disorders, skin and internal organ fibrosis, immune disorders, and a variety of other abnormalities. Symptoms vary widely among individuals, and personalized treatment is sought for each patient. Since there is no fundamental cure for SSc, it is designated as an intractable disease with patients receiving government subsidies for medical expenses in Japan. Oxidative stress (OS) has been reported to play an important role in the cause and symptoms of SSc. HOCl-induced SSc mouse models are known to exhibit skin and visceral fibrosis, vascular damage, and autoimmune-like symptoms observed in human SSc. The antioxidant combination Twendee X® (TwX) is a dietary supplement consisting of vitamins, amino acids, and CoQ10. TwX has been proven to prevent dementia in humans with mild cognitive impairment and significantly improve cognitive impairment in an Alzheimer's disease mouse model by regulating OS through a strong antioxidant capacity that cannot be achieved with a single antioxidant ingredient. We evaluated the effectiveness of TwX on various symptoms of HOCl-induced SSc mice. TwX-treated HOCl-induced SSc mice showed significantly reduced lung and skin fibrosis compared to untreated HOCl-induced SSc mice. TwX also significantly reduced highly oxidized protein products (AOPP) in serum and suppressed Col-1 gene expression and activation of B cells involved in autoimmunity. These findings suggest that TwX has the potential to be a new antioxidant treatment for SSc without side effects.

Update on Antioxidant Therapy with Edaravone: Expanding Applications in Neurodegenerative Diseases

The brain is susceptible to oxidative stress, which is associated with various neurological diseases. Edaravone (MCI-186, 3-methyl-1 pheny-2-pyrazolin-5-one), a free radical scavenger, has promising effects by quenching hydroxyl radicals (∙OH) and inhibiting both ∙OH-dependent and ∙OH-independent lipid peroxidation. Edaravone was initially developed in Japan as a neuroprotective agent for acute cerebral infarction and was later applied clinically to treat amyotrophic lateral sclerosis (ALS), a neurodegenerative disease. There is accumulating evidence for the therapeutic effects of edaravone in a wide range of diseases related to oxidative stress, including ischemic stroke, ALS, Alzheimer's disease, and placental ischemia. These neuroprotective effects have expanded the potential applications of edaravone. Data from experimental animal models support its safety for long-term use, implying broader applications in various neurodegenerative diseases. In this review, we explain the unique characteristics of edaravone, summarize recent findings for specific diseases, and discuss its prospects for future therapeutic applications.

Efficacy and safety of Y-2 sublingual tablet for patients with acute ischaemic stroke: protocol of a phase III randomised double-blind placebo-controlled multicentre trial

BACKGROUND AND PURPOSE

Clinical studies have demonstrated that edaravone dexborneol can improve the functional outcomes in patients with acute ischaemic stroke (AIS). The present clinical trial aimed at testing the efficacy and safety of Y-2 sublingual tablet on 90-day functional outcome in patients with AIS.

METHODS AND DESIGN

This is a randomised, double-blind, placebo-controlled, multicentre, parallel-group trial of Y-2 sublingual tablet on patients with AIS.An estimated 914 patients at age of 18-80 years with AIS within 48 hours after symptom onset from 40 hospitals will be randomly assigned to receive Y-2 sublingual tablet or placebo for 14 days. Patients are at score 6-20 points on National Institutes of Health Stroke Scale (NIHSS) and had a modified Rankin Scale (mRS) ≤1 before this stroke, except mechanical thrombectomy and neuroprotective agents treatment.

STUDY OUTCOMES

The primary outcome is the proportion of patients with mRS ≤1 on day 90 after randomisation. Secondary efficacy outcomes include mRS score on day 90, the proportion of patients with mRS ≤2 on day 90; the change of NIHSS score from baseline to day 14 and the proportion of patients with NIHSS score ≤1 at the days 14, 30 and 90.

DISCUSSION

This trial will provide valuable evidence for the efficacy and safety of Y-2 sublingual table for improving 90 days the functional outcomes in patients with AIS.

TRIAL REGISTRATION NUMBER

NCT04950920.

Sublingual Edaravone Dexborneol for the Treatment of Acute Ischemic Stroke: The TASTE-SL Randomized Clinical Trial

Importance

Sublingual edaravone dexborneol, which can rapidly diffuse and be absorbed through the oral mucosa after sublingual exposure, is a multitarget brain cytoprotection composed of antioxidant and anti-inflammatory ingredients edaravone and dexborneol.

Objective

To investigate the efficacy and safety of sublingual edaravone dexborneol on 90-day functional outcome in patients with acute ischemic stroke (AIS).

Design, Setting, and Participants

This was a double-blind, placebo-controlled, multicenter, parallel-group, phase 3 randomized clinical trial conducted from June 28, 2021, to August 10, 2022, with 90-day follow-up. Participants were recruited from 33 centers in China. Patients randomly assigned to treatment groups were aged 18 to 80 years and had a National Institutes of Health Stroke Scale score between 6 and 20, a total motor deficit score of the upper and lower limbs of 2 or greater, a clinically diagnosed AIS symptom within 48 hours, and a modified Rankin Scale (mRS) score of 1 or less before stroke. Patients who did not meet the eligibility criteria or declined to participate were excluded.

Intervention

Patients were assigned, in a 1:1 ratio, to receive sublingual edaravone dexborneol (edaravone, 30 mg; dexborneol, 6 mg) or placebo (edaravone, 0 mg; dexborneol, 60 μg) twice daily for 14 days and were followed up until 90 days.

Main Outcomes and Measures

The primary efficacy outcome was the proportion of patients with mRS score of 1 or less on day 90 after randomization.

Results

Of 956 patients, 42 were excluded. A total of 914 patients (median [IQR] age, 64.0 [56.0-70.0] years; 608 male [66.5%]) were randomly allocated to the edaravone dexborneol group (450 [49.2%]) or placebo group (464 [50.8%]). The edaravone dexborneol group showed a significantly higher proportion of patients experiencing good functional outcomes on day 90 after randomization compared with the placebo group (290 [64.4%] vs 254 [54.7%]; risk difference, 9.70%; 95% CI, 3.37%-16.03%; odds ratio, 1.50; 95% CI, 1.15-1.95, P = .003). The rate of adverse events was similar between the 2 groups (89.8% [405 of 450] vs 90.1% [418 of 464]).

Conclusion and Relevance

Among patients with AIS within 48 hours, sublingual edaravone dexborneol could improve the proportion of those achieving a favorable functional outcome at 90 days compared with placebo.

Trial Registration

ClinicalTrials.gov Identifier: NCT04950920.

Alleviated cerebral infarction in male mice lacking all nitric oxide synthase isoforms after middle cerebral artery occlusion

PURPOSE

The role of the nitric oxide synthases (NOSs) system in cerebral infarction has been examined in pharmacological studies with non-selective NOSs inhibitors. However, due to the non-specificity of the non-selective NOSs inhibitors, its role remains to be fully elucidated. We addressed this issue in mice in which neuronal, inducible, and endothelial NOS isoforms were completely disrupted.

METHODS AND RESULTS

We newly generated mice lacking all three NOSs by crossbreeding each single NOS-/- mouse. In the male, cerebral infarct size at 24 h after middle cerebral artery occlusion (MCAO) was significantly smaller in the triple n/i/eNOSs-/- genotype as compared with wild-type genotype. Neurological deficit score and mortality rate were also significantly lower in the triple n/i/eNOSs-/- than in the WT genotype. In contrast, in the female, there was no significant difference in the cerebral infarct size in the two genotypes. In the male triple n/i/eNOSs-/- genotype, orchiectomy significantly increased the cerebral infarct size, and in the orchiectomized male triple n/i/eNOSs-/- genotype, treatment with testosterone significantly reduced it. Cyclopaedic and quantitative comparisons of mRNA expression levels in cerebral infarct lesions between the male wild-type and triple n/i/eNOSs-/- genotypes at 1 h after MCAO revealed significant involvements of decreased oxidative stress and mitigated mitochondrial dysfunction in the alleviated cerebral infarction in the male triple n/i/eNOSs-/- genotype.

CONCLUSIONS

These results provide the first evidence that the NOSs system exerts a deleterious effect against acute ischemic brain injury in the male.

A protocol for directly accessing geminal C-4 diarylated pyrazol-5(4H)-ones via tandem C-H aryne insertion and their inceptive neurobiological evaluation

Geminal C-4 diarylation of substituted pyrazol-5(4H)-ones with in situ generated arynes as the aryl source has been achieved in a one-flask operation. All the newly accessed C4-gem-diarylated pyrazolone entities were found to be non-cytotoxic with varying AChE enzyme inhibitory activities and BBB permeability attributes that augur well for further advancement towards CNS therapeutics for untreatable disorders.

Endogenous defense mechanism-based neuroprotection in large-vessel acute ischemic stroke: A hope for future

BACKGROUND

Stroke is a leading cause of morbidity and mortality worldwide and a leading cause of disability. None of the neuroprotective agents have been approved internationally except edaravone in Japanese guidelines in acute ischemic stroke. We here discuss that there are two types of endogenous defense mechanisms (EDMs) after acute stroke for neuromodulation and neuroregeneration, and if both can be activated simultaneously, then we can have better recovery in stroke.

AIMS AND OBJECTIVES

We aimed to study the effect of combination of neuroprotection therapies acting on the two wings of EDM in acute large-vessel middle cerebral artery (LMCA) ischemic stroke.

METHODS

Sixty patients of LMCA stroke were enrolled and randomized within 72 h into two groups of 30 patients each. The control group received standard medical care without any neuroprotective agents while the intervention group received standard medical care combined with oral citicoline with vinpocetine for 3 months with initial 1 week intravenous and edaravone and cerebrolysin injection, started within 72 h of onset of stroke. Patients were assessed on the basis of the National Institutes of Health Stroke Scale, Fugl-Meyer Assessment Score, Glasgow Coma Scale, and Mini-Mental Status Examination at admission, discharge, and after 90 days.

RESULTS

The intervention group showed significant and early improvements in motor as well as cognitive recovery.

CONCLUSION

Combination therapy for neuroprotection which is acting on two pathways of EDM can be useful in functional recovery after acute ischemic stroke.

"No-reflow" phenomenon in acute ischemic stroke

Acute ischemic stroke (AIS) afflicts millions of individuals worldwide. Despite the advancements in thrombolysis and thrombectomy facilitating proximal large artery recanalization, the resultant distal hypoperfusion, referred to "no-reflow" phenomenon, often impedes the neurological function restoration in patients. Over half a century of scientific inquiry has validated the existence of cerebral "no-reflow" in both animal models and human subjects. Furthermore, the correlation between "no-reflow" and adverse clinical outcomes underscores the necessity to address this phenomenon as a pivotal strategy for enhancing AIS prognoses. The underlying mechanisms of "no-reflow" are multifaceted, encompassing the formation of microemboli, microvascular compression and contraction. Moreover, a myriad of complex mechanisms warrant further investigation. Insights gleaned from mechanistic exploration have prompted advancements in "no-reflow" treatment, including microthrombosis therapy, which has demonstrated clinical efficacy in improving patient prognoses. The stagnation in current "no-reflow" diagnostic methods imposes limitations on the timely application of combined therapy on "no-reflow" post-recanalization. This narrative review will traverse the historical journey of the "no-reflow" phenomenon, delve into its underpinnings in AIS, and elucidate potential therapeutic and diagnostic strategies. Our aim is to equip readers with a swift comprehension of the "no-reflow" phenomenon and highlight critical points for future research endeavors.

Development of Pharmacological Strategies with Therapeutic Potential in Ischemic Stroke

Acute ischemic stroke constitutes a health challenge with great social impact due to its high incidence, with the social dependency that it generates being an important source of inequality. The lack of treatments serving as effective neuroprotective therapies beyond thrombolysis and thrombectomy is presented as a need. With this goal in mind, our research group's collaborative studies into cerebral ischemia and subsequent reperfusion concluded that there is a need to develop compounds with antioxidant and radical scavenger features. In this review, we summarize the path taken toward the identification of lead compounds as potential candidates for the treatment of acute ischemic stroke. Evaluations of the antioxidant capacity, neuroprotection of primary neuronal cultures and in vivo experimental models of cerebral ischemia, including neurological deficit score assessments, are conducted to characterize the biological efficacy of the various neuroprotective compounds developed. Moreover, the initial results in preclinical development, including dose-response studies, the therapeutic window, the long-term neuroprotective effect and in vivo antioxidant evaluation, are reported. The results prompt these compounds for clinical trials and are encouraging regarding new drug developments aimed at a successful therapy for ischemic stroke.

Small molecules targeting different cellular pathologies for the treatment of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease in which the motor neuron circuitry displays progressive degeneration, affecting mostly the motor neurons in the brain and in the spinal cord. There are no effective cures, albeit three drugs, riluzole, edaravone, and AMX0035 (a combination of sodium phenylbutyrate and taurursodiol), have been approved by the Food and Drug Administration, with limited improvement in patients. There is an urgent need to build better and more effective treatment strategies for ALS. Since the disease is very heterogenous, numerous approaches have been explored, such as targeting genetic mutations, decreasing oxidative stress and excitotoxicity, enhancing mitochondrial function and protein degradation mechanisms, and inhibiting neuroinflammation. In addition, various chemical libraries or previously identified drugs have been screened for potential repurposing in the treatment of ALS. Here, we review previous drug discovery efforts targeting a variety of cellular pathologies that occur from genetic mutations that cause ALS, such as mutations in SOD1, C9orf72, FUS, and TARDP-43 genes. These mutations result in protein aggregation, which causes neuronal degeneration. Compounds used to target cellular pathologies that stem from these mutations are discussed and comparisons among different preclinical models are presented. Because the drug discovery landscape for ALS and other motor neuron diseases is changing rapidly, we also offer recommendations for a novel, more effective, direction in ALS drug discovery that could accelerate translation of effective compounds from animals to patients.

Favorable neuroprotective effect of intra-arterial application of edaravone dexborneol in ischemic stroke rats

OBJECTIVE

The aim of this study was to investigate the neuroprotective effects of intra-arterial administration of edaravone dexborneol in rats with acute ischemic stroke and determine the optimal dose.

MATERIALS AND METHODS

Firstly, 120 male Sprague-Dawley rats (265-300 g) were selected to establish ischemic stroke models and were randomly divided into groups of sham-operation (Sham group), cerebral ischemia-reperfusion (IS group), permanent focal ischemia (PI group) and treatment (2MG group: 2 mg/kg, 4MG group: 4 mg/kg, 6MG group: 6 mg/kg) groups. There are 20 rats in each group, and ten rats in each group were randomly selected for Longa score and 2,3,5-triphenyl tetrazolium chloride staining to observe the changes in neurological function and the proportion of cerebral infarct volume in each group. Secondly, the remaining ten rats in each group were scored for Longa and tested for free radicals (hydroxyl radical; peroxynitrite; nitric oxide) and pro-inflammatory cytokines (interleukin 6; interleukin-1β; tumor necrosis factor-α). We monitored changes in the indicators in each group of rats.

RESULTS

There were no significant differences among the enrolled Sprague-Dawley rats concerning age, sex, and feeding conditions. Edaravone dexborneol could significantly reduce the cerebral levels of hydroxyl radical, interleukin 6, interleukin-1β, tumor necrosis factor-α, and their behavioral scores of acute ischemic stroke rats after a single dose in the carotid artery. The results suggested that 4 mg/kg might be an appropriate dose.

CONCLUSIONS

A single intra-arterial administration of edaravone dexborneol can improve neurobehavioral function and alleviate cerebral injury in acute ischemic stroke rats through anti-inflammatory and free radical scavenging effects.

Therapeutic targeting of ALS pathways: Refocusing an incomplete picture

Numerous potential amyotrophic lateral sclerosis (ALS)-relevant pathways have been hypothesized and studied preclinically, with subsequent translation to clinical trial. However, few successes have been observed with only modest effects. Along with an improved but incomplete understanding of ALS as a neurodegenerative disease is the evolution of more sophisticated and diverse in vitro and in vivo preclinical modeling platforms, as well as clinical trial designs. We highlight proposed pathological pathways that have been major therapeutic targets for investigational compounds. It is likely that the failures of so many of these therapeutic compounds may not have occurred because of lack of efficacy but rather because of a lack of preclinical modeling that would help define an appropriate disease pathway, as well as a failure to establish target engagement. These challenges are compounded by shortcomings in clinical trial design, including lack of biomarkers that could predict clinical success and studies that are underpowered. Although research investments have provided abundant insights into new ALS-relevant pathways, most have not yet been developed more fully to result in clinical study. In this review, we detail some of the important, well-established pathways, the therapeutics targeting them, and the subsequent clinical design. With an understanding of some of the shortcomings in translational efforts over the last three decades of ALS investigation, we propose that scientists and clinicians may choose to revisit some of these therapeutic pathways reviewed here with an eye toward improving preclinical modeling, biomarker development, and the investment in more sophisticated clinical trial designs.

Effect of edaravone on symptomatic intracranial hemorrhage in patients with acute large vessel occlusion on apixaban for non-valvular atrial fibrillation

BACKGROUND

Edaravone administration was associated with lower incidence of symptomatic intracranial hemorrhage (sICH) in patients with acute large vessel occlusion (LVO). However, its protective effect on sICH in patients with LVO who receive direct oral anticoagulants for non-valvular atrial fibrillation (NVAF) is uncertain.

OBJECTIVES

To explore the effect of edaravone administration on the incidence of sICH in patients with acute LVO receiving apixaban for NVAF.

METHODS

A Japanese multicenter registry of apixaban on clinical outcome of the patients with LVO or stenosis (ALVO study) included patients who were admitted within 24 h after stroke onset and were received apixaban within 14 days of stroke onset. Patients were divided into two groups according to edaravone administration (Edaravone and No-Edaravone groups). The incidence of sICH within one year and infarct growth before apixaban administration were compared between these groups.

RESULTS

Of the 686 enrolled patients, 622 were included and edaravone was administered to 407 (65.4%). The incidences of sICH in Edaravone and No-Edaravone groups were 1.3% and 5.0%, respectively (p = 0.01). The inverse probability of treatment-weighting (IPTW) hazard ratio (HR) (95% confidence interval [CI]) of Edaravone group for sICH within one year was 0.36 (0.15-0.80) compared to No-Edaravone group. The incidences of infarct growth in Edaravone and No-Edaravone groups were 35.3% and 42.0%, respectively (p = 0.13). IPTW HR (95% CIs) for infarct growth was 0.76 (0.60-0.97).

CONCLUSIONS

Edaravone administration was associated with a lower incidence of sICH in patients with LVO and NVAF who administrated apixaban.

Mitochondrial Calcium Overload Plays a Causal Role in Oxidative Stress in the Failing Heart

Heart failure is a serious global health challenge, affecting more than 6.2 million people in the United States and is projected to reach over 8 million by 2030. Independent of etiology, failing hearts share common features, including defective calcium (Ca2+) handling, mitochondrial Ca2+ overload, and oxidative stress. In cardiomyocytes, Ca2+ not only regulates excitation-contraction coupling, but also mitochondrial metabolism and oxidative stress signaling, thereby controlling the function and actual destiny of the cell. Understanding the mechanisms of mitochondrial Ca2+ uptake and the molecular pathways involved in the regulation of increased mitochondrial Ca2+ influx is an ongoing challenge in order to identify novel therapeutic targets to alleviate the burden of heart failure. In this review, we discuss the mechanisms underlying altered mitochondrial Ca2+ handling in heart failure and the potential therapeutic strategies.

Edaravone administration and its potential association with a new clinical syndrome in cerebral infarction patients: Three case reports

BACKGROUND

Edaravone is a widely used treatment for patients with cerebral infarction and, in most cases, edaravone-induced side effects are mild. However, edaravone-related adverse reactions have been receiving increasing attention.

CASE SUMMARY

We treated three patients with acute cerebral infarction who died following treatment with edaravone. Edaravone is a widely used treatment for patients with cerebral infarction and, in most cases, edaravone-induced side effects are mild. However, edaravone-related adverse reactions have been receiving increasing attention.

CONCLUSION

Our cases highlight the importance of educating clinicians regarding the new edaravone-induced clinical syndromes of cerebral infarction as potentially fatal adverse drug reactions. Considering that no laboratory or confirmatory test exists to diagnose edaravone-induced death from cerebral infarction, clinicians’ knowledge is the key element in recognizing this phenomenon.

Pathophysiology and Optimal Treatment of Intracranial Branch Atheromatous Disease

Intracranial branch atheromatous disease (BAD) is a pathological condition characterized by the occlusion of a relatively large perforating branch (700-800 µm) near the orifice of a parent artery due to atherosclerotic plaque-based thrombus (microatheroma). BAD is refractory to treatment and follows a course of progressive exacerbation, especially motor paralysis. Uniform treatment for common atherothrombotic cerebral infarction or lacunar infarction does not prevent the progressive exacerbation of BAD, and consequently affects functional prognosis. To date, various combinations of treatments have been investigated and proposed to attenuate the worsening symptoms of BAD. However, no therapy with established efficacy is yet available for BAD. Since it is the most difficult condition to treat in the area of cerebral infarction, the establishment of optimal treatment methods for BAD is keenly awaited. This review presents an overview of the acute treatments available for BAD and discusses the prospects for optimal treatment.

Development of Edaravone Ionic Liquids and Their Application for the Treatment of Cerebral Ischemia/Reperfusion Injury

Preparation of the ionic liquid (IL) form of active pharmaceutical ingredients (APIs), termed API-IL, has attracted attention because it can improve upon certain disadvantages of APIs, such as poor water solubility and low stability. Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a clinically approved cerebroprotective agent against ischemic stroke and amyotrophic lateral sclerosis, while new formulations that enable improvement of its physicochemical properties and biodistribution are desired. Herein, we report a newly developed API-IL of edaravone (edaravone-IL), in which edaravone is used as an anionic molecule. We investigated the physicochemical properties of edaravone-IL and its therapeutic effect against cerebral ischemia/reperfusion (I/R) injury, a secondary injury after an ischemic stroke. Among the cationic molecules used for edaravone-IL preparation, the IL prepared with tetrabutylphosphonium cation existed as a liquid at room temperature, and significantly increased the water solubility of edaravone without decreasing its antioxidative activity. Importantly, edaravone-IL formed negatively charged nanoparticles upon suspension in water. Intravenous administration of edaravone-IL showed significantly higher blood circulation time and lower distribution in the kidney compared with edaravone solution. Moreover, edaravone-IL significantly suppressed brain cell damage and motor functional deficits in model rats of cerebral I/R injury and showed comparable cerebroprotective effect to edaravone. Taken together, these results suggest that edaravone-IL could be a new form of edaravone with superior physicochemical properties and could be useful for the treatment of cerebral I/R injury.

Multi-pathway neuroprotective effects of a novel salidroside derivative SHPL-49 against acute cerebral ischemic injury

SHPL-49 ((2R,3S,4S,5R,6R)-2-(hydroxymethyl)-6-(4-(4-methoxyphenyl) butoxy) tetrahydro-2H-pyran-3,4,5-triol) is a novel glycoside derivative obtained from structural modification of salidroside, which is isolated from the medicinal plant Rhodiola rosea L. SHPL-49 was administered to rats with permanent middle cerebral artery occlusion (pMCAO) for 5 days, and it was found that SHPL-49 could alleviate the cerebral infarct volume and reduce the neurological deficit score. Moreover, the effective time window of SHPL-49 in the pMCAO model was from 0.5 to 8 h after embolization. In addition, the result of immunohistochemistry showed that SHPL-49 could increase the number of neurons in the brain tissue and reduce the occurrence of apoptosis. Morris water maze and Rota-rod experiments showed that SHPL-49 could improve neurological deficits, repair neurocognitive and motor dysfunction, and enhance learning and memory ability in the pMCAO model after 14 days of SHPL-49 treatment. Further in vitro experiments showed that SHPL-49 significantly reduced the calcium overload of PC-12 cells and the production of reactive oxygen species (ROS) induced by oxygen and glucose deprivation (OGD), and increased the levels of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), decreased the production of malondialdehyde (MDA). Furthermore, SHPL-49 could reduce cell apoptosis by increasing protein expression ratio of anti-apoptotic factor Bcl-2 to pro-apoptotic factor Bax in vitro. SHPL-49 also regulated the expression of Bcl-2 and Bax in ischemic brain tissue, and even inhibited the caspase cascade of pro-apoptotic proteins Cleaved-caspase 9 and Cleaved-caspase 3. Taken together, SHPL-49 exhibited neuroprotective effects against cerebral ischemic injury through multiple pathways, such as alleviating calcium overload, reducing oxidative stress damage, and inhibiting apoptosis.

Edaravone combined with Shuxuening versus edaravone alone in the treatment of acute cerebral infarction: A systematic review and meta-analysis

BACKGROUND

Shuxuening injection (SXN) is a traditional Chinese medicine used in the treatment of cardiovascular diseases. Whether it can provide better outcomes when combined with edaravone injection (ERI) for the treatment of acute cerebral infarction is not well determined. Therefore, we evaluated the efficacy of ERI combined with SXN versus that of ERI alone in patients with acute cerebral infarction.

METHODS

PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, and Wanfang electronic databases were searched up to July 2022. Randomized controlled trials comparing the outcomes of efficacy rate, neurologic impairment, inflammatory factors, and hemorheology were included. Odds ratio or standard mean difference (SMD) with corresponding 95% confidence intervals (CIs) were used to present the overall estimates. The quality of the included trials was evaluated by the Cochrane risk of bias tool. The study was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses.

RESULTS

Seventeen randomized controlled trials were included consisting of 1607 patients. Compared to ERI alone, treatment with ERI plus SXN had a greater effective rate than ER alone (odds ratio = 3.94; 95% CI: 2.85, 5.44; I2 = 0%, P < .00001), a lower National Institute of Health Stroke Scale (SMD= -1.39; 95% CI: -1.73, -1.05; I2 = 71%, P < .00001), lower neural function defect score (SMD= -0.75; 95% CI: -1.06,-0.43; I2 = 67%, P < .00001), and lower level of neuron-specific enolase (SMD= -2.10; 95% CI: -2.85, -1.35; I2 = 85%, P < .00001). ERI plus SXN treatment provided significant improvements in whole blood high shear viscosity (SMD = -0.87; 95% CI: -1.17, -0.57; I2 = 0%, P < .00001), and whole blood low shear viscosity (SMD = -1.50; 95% CI: -1.65, -1.36; I2 = 0%, P < .00001) compared to ERI alone.

CONCLUSION

ERI plus SXN showed better efficacy than ERI alone for patients with acute cerebral infarction. Our study provides evidence supporting the application of ERI plus SXN for acute cerebral infarction.

Recurrent embolic stroke associated with adenomyosis: A single case report and literature review

INTRODUCTION

Uterine adenomyosis is a benign disorder in which endometrial glands and stroma are present within the myometrium. There have been several case reports of cerebral infarction associated with adenomyosis, but their clinical characteristics, optimal treatment, and prognosis have not been systematically reviewed.

METHODS

A case of cerebral infarction with adenomyosis is reported, and a comprehensive systematic literature search using the PubMed database was conducted.

RESULTS

A 42-year-old woman, previously diagnosed with adenomyosis, developed multiple cerebral infarctions during menstruation. Her CA125 level was 293 U/mL, and treatment with edoxaban 30 mg was started. Seven days after hospital discharge, she had her subsequent menstrual period and then developed a recurrent stroke. Her CA125 level was 743 U/mL on readmission. A hysterectomy was performed, and the patient has had no further stroke recurrence. A systematic review identified 19 cases with cerebral infarction associated with adenomyosis, including the present case. The patients' clinical characteristics included young age (44.7 ± 6.2 years), stroke development during menstruation (85%), multiple infarctions affecting ≥ 3 vessel territories (39%), and high levels of CA125 and D-dimer (810.6 ± 888.4 U/mL, and 10.3 ± 18.6 μg/mL, respectively). Antithrombotic therapy was given to 14 patients, but recurrent stroke occurred in 5 (36%) patients. Hysterectomy was conducted in 5 and 4 patients with initial and recurrent stokes, respectively, and there were no further recurrences thereafter.

CONCLUSION

Cerebral infarction associated with adenomyosis has specific clinical characteristics. Antithrombotic therapy was insufficient, and hysterectomy should particularly be considered in cases of recurrent stroke.

Edaravone Attenuates Aβ 1-42-Induced Inflammatory Damage and Ferroptosis in HT22 Cells

Ferroptosis and neuroinflammation play a crucial role in the pathogenesis of Alzheimer's disease (AD), and Edaravone (EDA) has been demonstrated to have anti-inflammatory, antioxidant and neuroprotective effects in neurodegenerative diseases. However, the relationship between EDA and ferroptosis in AD is unidentified. This research aimed to elucidate the mechanism of EDA in AD with Aβ 1-42-induced HT22 cells as in vitro cell model. The results showed that EDA could significantly reduce Aβ_1-42-induced apoptosis of HT22 cells and formation of pro-inflammatory factors TNF-α, IL-1β and IL-6, prevent the activation of TLR4/NF-κB /NLRP3 signaling pathway, and inhibit ferroptosis and lipid peroxidation. Taken together, EDA contributes to inhibiting neuroinflammatory injury and ferroptosis in Aβ 1-42-induced HT22 cells, and thus may be a potential candidate for the treatment of AD.

Pharmacological Strategies for Stroke Intervention: Assessment of Pathophysiological Relevance and Clinical Trials

OBJECTIVES

The present review describes stroke pathophysiology in brief and discusses the spectrum of available treatments with different promising interventions that are in clinical settings or are in clinical trials.

METHODS

Relevant articles were searched using Google Scholar, Cochrane Library, and PubMed. Keywords for the search included ischemic stroke, mechanisms, stroke interventions, clinical trials, and stem cell therapy.

RESULTS AND CONCLUSION

Stroke accounts to a high burden of mortality and morbidity around the globe. Time is an important factor in treating stroke. Treatment options are limited; however, agents with considerable efficacy and tolerability are being continuously explored. With the advances in stroke interventions, new therapies are being formulated with a hope that these may aid the ongoing protective and reparative processes. Such therapies may have an extended therapeutic time window in hours, days, weeks, or longer and may have the advantage to be accessible by a majority of the patients.

Sodium formononetin-3'-sulphonate alleviates cerebral ischemia-reperfusion injury in rats via suppressing endoplasmic reticulum stress-mediated apoptosis

BACKGROUND

Sodium formononetin-3'-sulphonate (Sul-F) may alleviate I/R injury in vivo with uncertain mechanism. Endoplasmic reticulum (ER) stress-mediated apoptosis participates in the process of cerebral ischemia-reperfusion (I/R) injury. Our aim is to figure out the effect of Sul-F on cerebral I/R injury and to verify whether it works through suppressing ER stress-mediated apoptosis.

RESULTS

The cerebral lesions of middle cerebral artery occlusion (MCAO) model in SD rats were aggravated after 24 h of reperfusion, including impaired neurological function, increased infarct volume, intensified inflammatory response and poor cell morphology. After intervention, the edaravone (EDA, 3 mg/kg) group and Sul-F high-dose (Sul-F-H, 80 mg/kg) group significantly alleviated I/R injury via decreasing neurological score, infarct volume and the serum levels of inflammatory factors (TNF-α, IL-1β and IL-6), as well as alleviating pathological injury. Furthermore, the ER stress level and apoptosis rate were elevated in the ischemic penumbra of MCAO group, and were significantly blocked by EDA and Sul-F-H. In addition, EDA and Sul-F-H significantly down-regulated the ER stress related PERK/eIF2α/ATF4 and IRE1 signal pathways, which led to reduced cell apoptosis rate compared with the MCAO group. Furthermore, there was no difference between the EDA and Sul-F-H group in terms of therapeutic effect on cerebral I/R injury, indicating a therapeutic potential of Sul-F for ischemic stroke.

CONCLUSIONS

Sul-F-H can significantly protects against cerebral I/R injury through inhibiting ER stress-mediated apoptosis in the ischemic penumbra, which might be a novel therapeutic target for ischemic stroke.

Edaravone protects against liver fibrosis progression via decreasing the IL-1β secretion of macrophages

Edaravone (EDA), a strong novel free radical scavenger, have been demonstrated to exert neurovascular protective effects clinically. Furthermore, EDA can suppress the lung injury, pulmonary fibrosis and skin fibrosis, while the precise effects and mechanisms of EDA on liver injury and fibrosis remain unclear. The effects of EDA on the Thioacetamide (TAA)-induced liver fibrosis were evaluated by sirius red staining, α-SMA immunohistochemistry. The percentages of immune cell subsets were analyzed by flow cytometry. Immunofluorescence assay was performed to identify the fibrotic properties of hepatic stellate cells (HSCs). Western blot and qPCR were used to detect the levels of liver fibrosis-related molecules and IL-1β. EDA displayed a hepatic protective role in TAA-induced chronic liver fibrosis via inhibiting monocyte/macrophages recruitment and IL-1β production of macrophages. Mechanically, EDA inhibited of NF-κB signal pathway and reactive oxygen species (ROS) production in macrophages. Moreover, EDA treatment indirectly suppressed the activation of HSCs by decreasing the IL-1β secretion of macrophages. Together, EDA protects against TAA-induced liver fibrosis via decreasing the IL-1β production of macrophages, thereby providing a feasible solution for clinical treatment of liver fibrosis.

Ischemic Stroke, Lessons from the Past towards Effective Preclinical Models

Ischemic stroke is a leading cause of death worldwide, mainly in western countries. So far, approved therapies rely on reperfusion of the affected brain area, by intravenous thrombolysis or mechanical thrombectomy. The last approach constitutes a breakthrough in the field, by extending the therapeutic window to 16-24 h after stroke onset and reducing stroke mortality. The combination of pharmacological brain-protective strategies with reperfusion is the future of stroke therapy, aiming to reduce brain cell death and decrease patients' disabilities. Recently, a brain-protective drug-nerinetide-reduced brain infarct and stroke mortality, and improved patients' functional outcomes in clinical trials. The success of new therapies relies on bringing preclinical studies and clinical practice close together, by including a functional outcome assessment similar to clinical reality. In this review, we focused on recent upgrades of in vitro and in vivo stroke models for more accurate and effective evaluation of therapeutic strategies: from spheroids to organoids, in vitro models that include all brain cell types and allow high throughput drug screening, to advancements in in vivo preclinical mouse stroke models to mimic the clinical reality in surgical procedures, postsurgical care, and functional assessment.

Induction of JAK2/STAT3 pathway contributes to protective effects of different therapeutics against myocardial ischemia/reperfusion

Insufficiency in coronary blood supply results in myocardial ischemia and consequently, various clinical syndromes and irreversible injuries. Myocardial damage occurs as a result of two processes during acute myocardial infarction (MI): ischemia and subsequent reperfusion. According to the available evidence, oxidative stress, excessive inflammation reaction, reactive oxygen species (ROS) generation, and apoptosis are crucial players in the pathogenesis of myocardial ischemia/reperfusion (IR) injury. There is emerging evidence that Janus tyrosine kinase 2 (JAK2) signal transducer and activator of the transcription 3 (STAT3) pathway offers cardioprotection against myocardial IR injury. This article reviews therapeutics that exert cardioprotective effects against myocardial IR injury through induction of JAK2/STAT3 pathway.

Edaravone Dexborneol Alleviates Cerebral Ischemic Injury via MKP-1-Mediated Inhibition of MAPKs and Activation of Nrf2

The edaravone and dexborneol concentrated solution for injection (edaravone-dexborneol) is a medication used clinically to treat neurological impairment induced by ischemic stroke. This study was aimed at investigating the preventive effects and the underlying mechanisms of edaravone-dexborneol on cerebral ischemic injury. A rat four-vessel occlusion (4-VO) model was established, and the neuronal injury and consequent neurological impairment of rats was investigated. Brain tissue malondialdehyde (MDA), myeloperoxidase (MPO), and nitric oxide (NO) levels were determined. The levels of proteins in mitogen-activated protein kinases (MAPKs), nuclear factor erythroid 2-related factor 2 (Nrf2), and nuclear factor-κB (NF-κB) signaling pathways were determined by western immunoblotting. The function of mitogen-activated protein kinase phosphatase 1 (MKP-1) was investigated using both western blot and immunofluorescence methods, and the effect of the MKP-1 inhibitor, (2E)-2-benzylidene-3-(cyclohexylamino)-3H-inden-1-one (BCI), was investigated. The results indicated that edaravone-dexborneol alleviated neurological deficiency symptoms and decreased apoptosis and neuron damage in the hippocampal CA1 area of the ischemic rats. Edaravone-dexborneol increased the MKP-1 level; decreased the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (p38 MAPK); inhibited NF-κB p65 activation; and boosted Nrf2 activation, all of which were partially reversed by the MKP-1 inhibitor, BCI. The above results indicated that the upregulation of MKP-1 contributed to the protective effects of edaravone-dexborneol against ischemic brain injury. Our findings support the hypothesis that edaravone-dexborneol can alleviate cerebral ischemic injury via the upregulation of MKP-1, which inhibits MAPKs and activates Nrf2.

Ferritin-mediated iron detoxification promotes hypothermia survival in Caenorhabditis elegans and murine neurons

How animals rewire cellular programs to survive cold is a fascinating problem with potential biomedical implications, ranging from emergency medicine to space travel. Studying a hibernation-like response in the free-living nematode Caenorhabditis elegans, we uncovered a regulatory axis that enhances the natural resistance of nematodes to severe cold. This axis involves conserved transcription factors, DAF-16/FoxO and PQM-1, which jointly promote cold survival by upregulating FTN-1, a protein related to mammalian ferritin heavy chain (FTH1). Moreover, we show that inducing expression of FTH1 also promotes cold survival of mammalian neurons, a cell type particularly sensitive to deterioration in hypothermia. Our findings in both animals and cells suggest that FTN-1/FTH1 facilitates cold survival by detoxifying ROS-generating iron species. We finally show that mimicking the effects of FTN-1/FTH1 with drugs protects neurons from cold-induced degeneration, opening a potential avenue to improved treatments of hypothermia.

Strategies to improve cold resistance are of potential biomedical interest. Here the authors demonstrate that ferritin-mediated detoxification of iron, preventing the generation of reactive oxygen species, promotes cold survival in both Caenorhabditis elegans and cultured mammalian neurons.

Distribution-Free Approach to the Design and Analysis of Randomized Stroke Trials With the Modified Rankin Scale

BACKGROUND

Many methods have been suggested for analyzing the modified Rankin Scale (mRS). However, there lacks a unified approach to analysis and sample size determination that properly uses the ordinal nature of the data. We propose a simple method for CI estimation and corresponding sample size determination.

METHODS

We quantify treatment effect by the win probability (WinP) that a randomly selected patient in the treatment group has an equal or a better mRS score than a patient in the control group. Thus, a win probability of 0.5 means no effect, likened to a draw in competitive sports. We estimate the win probability and its SE based on the ranks of mRS scores, where tied scores are handled by average ranks. Corresponding methods for hypothesis testing, CI estimation, and sample size determination are derived. The methods are evaluated with a simulation study based on real data from 10 randomized stroke trials that used mRS as the outcome measure.

RESULTS

Simulation results demonstrated that the methods performed very well in terms of CI coverage, tail errors, and assurance to achieving the prespecified precision. Because the methods are very simple, we implemented them in an Excel spreadsheet, requiring only user inputs on frequencies of mRS scores in 2 comparison groups.

CONCLUSIONS

Sound statistical methods are important for the success of randomized stroke trials. The proposed methods and associated spreadsheet should prove useful for stroke researchers in the planning and analysis of randomized trials. Meta-analysis has also been made easy for trials with ordinal scores.

Roots of Astragalus propinquus Schischkin Regulate Transmembrane Iron Transport and Ferroptosis to Improve Cerebral Ischemia-Reperfusion Injury

Background

The dried roots of the Astragalus propinquus Schischkin (RAP) plant, as a traditional Chinese medicine, has been widely used to treat stroke, cerebral ischemia, qi deficiency, and hypertension. Buyang Huanwu decoction is traditionally used to treat stroke in China for more than 200 years and has a significant effect on cerebral ischemia, and RAP is monarch medicine of Buyang Huanwu decoction. Therefore, this study was designed to observe the regulatory effect of RAP on transmembrane iron transporters and ferroptosis-related factors in cerebral ischemia-reperfusion injury (CIRI) in rats.

Methods

Middle cerebral artery occlusion (MCAO) was used to block blood flow in the blood supply area of the middle cerebral artery in seventy male SD rats to induce focal CIRI to establish a rat model of CIRI. RAP was administered to explore the regulatory effect of RAP on iron transmembrane transport under the condition of CIRI. The infarct size was measured using 2,3,5-triphenyl-tetrazolium chloride (TTC) staining, the pathological structure of brain tissue was observed by HE staining, and neuronal injury was evaluated by Nissl staining after treatment. Then, changes in the iron transporters ferritin (Fn), ferritin heavy chain (FHC), ferritin light chain (FLC), transferrin (Tf), transferrin receptor (TfR), divalent metal transporter 1 (DMT1), L-type calcium channel (LTCC), transient receptor potential canonical 6 (TRPC6), and ferroportin 1 (FPN1) were observed by immunohistochemistry staining (IHC) and Western blotting. The expression of key factors of ferroptosis, including the membrane sodium-dependent cystine/glutamate antiporter System Xc⁻ (System Xc⁻) light chain subunit (XCT) and heavy chain subunit (SLC3A2), glutathione peroxidase 4 (GPX4), nuclear factor erythroid 2-related factor (NRF2), heme oxygenase-1 (HO-1), and iron-responsive element-binding protein 2 (IREB2) in the brain tissues of rats was assessed by Western blotting. RAP decreased the infarct size and neuronal injury after CIRI in rats. Similarly, RAP treatment regulated the expression of iron transporters. As such, RAP was able to reduce the expression of Fn, FHC, FLC, Tf, TfR, DMT1, and TRPC6 and increase the expression of FPN1 through a Tf/TfR-independent pathway after CIRI in rats.

Conclusion

RAP stimulation inhibited ferroptosis by regulating the expression of the key ferroptosis factors XCT, SLC3A2, GPX4, NRF2, HO-1, and IREB2. In conclusion, RAP regulates transmembrane iron transport and ferroptosis to improve CIRI.

The Role and Therapeutic Potential of the Integrated Stress Response in Amyotrophic Lateral Sclerosis

In amyotrophic lateral sclerosis (ALS) patients, loss of cellular homeostasis within cortical and spinal cord motor neurons triggers the activation of the integrated stress response (ISR), an intracellular signaling pathway that remodels translation and promotes a gene expression program aimed at coping with stress. Beyond its neuroprotective role, under regimes of chronic or excessive stress, ISR can also promote cell/neuronal death. Given the two-edged sword nature of ISR, many experimental attempts have tried to establish the therapeutic potential of ISR enhancement or inhibition in ALS. This review discusses the complex interplay between ISR and disease progression in different models of ALS, as well as the opportunities and limitations of ISR modulation in the hard quest to find an effective therapy for ALS.

Secondary Brain Injury by Oxidative Stress After Cerebral Hemorrhage: Recent Advances

Intracerebral hemorrhage (ICH) is a clinical syndrome in which blood accumulates in the brain parenchyma because of a nontraumatic rupture of a blood vessel. Because of its high morbidity and mortality rate and the lack of effective therapy, the treatment of ICH has become a hot research topic. Meanwhile, Oxidative stress is one of the main causes of secondary brain injury(SBI) after ICH. Therefore, there is a need for an in-depth study of oxidative stress after ICH. This review will discuss the pathway and effects of oxidative stress after ICH and its relationship with inflammation and autophagy, as well as the current antioxidant therapy for ICH with a view to deriving better therapeutic tools or targets for ICH.

Edaravone for acute ischemic stroke - Systematic review with meta-analysis

INTRODUCTION

Ischemic stroke is a major cause of death and disability. Despite major advances in reperfusion therapies, most patients don´t benefit from these treatments as the time window for such interventions is limited. Therefore, other treatment options are desirable. Edaravone has been demonstrated in previous studies to reduce neurologic deficits in stroke patients.

OBJECTIVE

To test the hypothesis that edaravone reduces functional dependence in ischemic stroke patients.

MATERIAL AND METHODS

Systematic review and meta-analysis of randomized controlled trials and observational studies comparing edaravone to placebo in adult patients with ischemic stroke. The efficacy outcomes of interest were good and excellent functional outcomes at 90 days, defined as modified Rankin Scale (mRS) scores of 0-2 and 0-1 respectively. The safety outcomes of interest were intracranial hemorrhage and mortality.

RESULTS

19 studies were included. Edaravone treatment was associated with improved chances of 90-day good (OR=1.31, 95% CI 1.06-1.67) and excellent (OR=1.26, 95% CI 1.04-1.54) functional outcomes. Mortality was also lower in edaravone treated patients (OR=0.50, 95% CI 0.45-0.56). There were no differences in terms of intracranial hemorrhage. Most studies were observational and performed in Asian populations, especially Japan. Heterogeneity was high for all outcomes but reduced when analysis was restricted to randomized trials.

CONCLUSION

Edaravone is a promising treatment for ischemic stroke patients, with a more favorable time window. However, more randomized studies including patient populations outside Asia are required to confirm this hypothesis.

Edaravone dexborneol protects cerebral ischemia reperfusion injury through activating Nrf2/HO-1 signaling pathway in mice

Stroke is the leading cause of disability and death. When blood flow is restored after prolonged ischemia and hypoxia, it leads to excessive production of reactive oxygen species (ROS), increased local inflammation, and apoptosis, which are the cause of most cerebral ischemia reperfusion injury (CIRI), leading to secondary brain tissue damage. Edaravone dexborneol is a novel neuroprotective agent consisting of edaravone and borneol. Studies have shown that it has synergistic antioxidant and anti‐inflammatory effects. However, whether Edaravone dexborneol stimulates the Nrf2/HO‐1 pathway to regulate NADPH oxidase 2 (NOX2) remains unclear. In this study, wild‐type (WT) mice and Nrf2 knockout (KO) mice were used to investigate the antioxidant, anti‐inflammatory, and anti‐apoptotic effects of Edaravone dexborneol on CIRI and its mechanism. The cognitive function of mice was evaluated with the Morris water maze (MWM), test and the cell structures of hippocampus were observed by hematoxylin and eosin (H&E) staining. Nrf2, HO‐1, and NOX2 proteins and apoptosis‐related proteins Bcl‐2, Bax, and Caspase 3 were detected by western blotting. Nrf2, HO‐1, NOX2, and inflammatory factors TNF‐α, IL‐1β, IL‐4, and IL‐10 were detected by real‐time polymerase chain reaction. The results showed that Edaravone dexborneol treatment improved learning and memory performance, neuronal damage, and enhanced antioxidant, inflammation, and apoptosis in CIRI mice. In addition, Edaravone dexborneol induced the activation Nrf2/HO‐1 signaling pathway activation while inhibiting NOX2 expression. Overall, these results indicate that Edaravone dexborneol ameliorates CIRI‐induced memory impairments by activating Nrf2/HO‐1 signaling pathway and inhibiting NOX2.

Evaluation of anti-inflammatory diphenyldihaloketone EF24 in transient ischemic stroke model

OBJECTIVES

Revascularization is necessary in patients with ischemic stroke, however it does not address inflammation that contribute to reperfusion injury and the early growth of ischemic core. We investigated EF24, an anti-inflammatory agent, in a stroke model.

METHODS

Ischemic stroke was induced in mice by occluding middle cerebral artery for 1 h followed by reperfusion. EF24 was given either 10 min post-reperfusion (EF24_Post) or 10 min before occlusion (prophylactic, EF24_Pro). Survival, ipsilateral uptake of radioactive infarct marker ¹⁸F-fluoroglucaric acid (FGA), inflammatory cytokines, and tetrazolium chloride (TTC) staining were assessed.

RESULTS

Survival was increased in both EF24-treated groups compared to the stroke+vehicle group. Ipsilateral ¹⁸F-FGA uptake increased 2.6-fold in stroke+vehicle group compared to sham group (p < 0.05); the uptake in EF24-treated groups and sham group was not significantly different. TTC-staining also showed reduction in infarct size by EF24 treatment. Plasma IL-6, TNF-α, and corticosterone did not show significant changes among groups. However, ipsilateral tissue in stroke+vehicle mice showed increased IL-6 (>90-fold) and TNF-α (3-fold); the tissue IL-6 and TNF-α were significantly reduced in stroke+EF24_Pro and stroke+EF24_Post groups. ¹⁸F-FGA uptake significantly correlated with tissue IL-6 levels.

CONCLUSIONS

EF24 controls infarct growth and suppresses tissue inflammation in ischemic stroke, which can be monitored by ¹⁸F-FGA uptake.

Application and Utility of Liposomal Neuroprotective Agents and Biomimetic Nanoparticles for the Treatment of Ischemic Stroke

Ischemic stroke is still one of the leading causes of high mortality and severe disability worldwide. Therapeutic options for ischemic stroke and subsequent cerebral ischemia/reperfusion injury remain limited due to challenges associated with drug permeability through the blood-brain barrier (BBB). Neuroprotectant delivery with nanoparticles, including liposomes, offers a promising solution to address this problem, as BBB disruption following ischemic stroke allows nanoparticles to pass through the intercellular gaps between endothelial cells. To ameliorate ischemic brain damage, a number of nanotherapeutics encapsulating neuroprotective agents, as well as surface-modified nanoparticles with specific ligands targeting the injured brain regions, have been developed. Combination therapy with nanoparticles encapsulating neuroprotectants and tissue plasminogen activator (t-PA), a globally approved thrombolytic agent, has been demonstrated to extend the narrow therapeutic time window of t-PA. In addition, the design of biomimetic drug delivery systems (DDS) employing circulating cells (e.g., leukocytes, platelets) with unique properties has recently been investigated to overcome the injured BBB, utilizing these cells’ inherent capability to penetrate the ischemic brain. Herein, we review recent findings on the application and utility of nanoparticle DDS, particularly liposomes, and various approaches to developing biomimetic DDS functionalized with cellular membranes/membrane proteins for the treatment of ischemic stroke.

Current Drug Repurposing Strategies for Rare Neurodegenerative Disorders

Rare diseases are life-threatening or chronically debilitating low-prevalent disorders caused by pathogenic mutations or particular environmental insults. Due to their high complexity and low frequency, important gaps still exist in their prevention, diagnosis, and treatment. Since new drug discovery is a very costly and time-consuming process, leading pharmaceutical companies show relatively low interest in orphan drug research and development due to the high cost of investments compared to the low market return of the product. Drug repurposing–based approaches appear then as cost- and time-saving strategies for the development of therapeutic opportunities for rare diseases. In this article, we discuss the scientific, regulatory, and economic aspects of the development of repurposed drugs for the treatment of rare neurodegenerative disorders with a particular focus on Huntington’s disease, Friedreich’s ataxia, Wolfram syndrome, and amyotrophic lateral sclerosis. The role of academia, pharmaceutical companies, patient associations, and foundations in the identification of candidate compounds and their preclinical and clinical evaluation will also be discussed.