Inhibitory effect of MCI-186, a free radical scavenger, on cerebral ischemia following rat middle cerebral artery occlusion

Targeting MAD2B as a strategy for ischemic stroke therapy

INTRODUCTION

Post-stroke cognitive impairment is one of the major causes of disability due to cerebral ischemia. MAD2B is an inhibitor of Cdh1/APC, and loss of Cdh1/APC function in mature neurons increases ROCK2 activity, leading to changes in synaptic plasticity and memory loss in mouse neurons. Whether MAD2B regulates learning memory capacity through ROCK2 in cerebral ischemia is not known.

OBJECTIVES

We investigated the role and mechanism of MAD2B in cerebral ischemia-induced cognitive dysfunction.

METHODS

The expression of MAD2B and its downstream related molecules was detected by immunoblotting and intervened with neuroprotectants after middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation/reoxygenation (OGD/R). We constructed MAD2B-cKO-specific knockout mice, knocked down and overexpressed MAD2B in mouse hippocampus by lentiviral injection in brain stereotaxis, modeled cerebral ischemia by using MCAO, and explored the role of MAD2B in post-stroke cognitive impairment (PSCI) by animal behaviors such as Y-maze and Novel object recognition test. Then the expression of MAD2B/ROCK2, downstream molecules and apoptosis-related molecules was detected. Finally, ROCK2 expression was intervened using its inhibitor and shRNA-ROCK2 lentivirus.

RESULTS

The expression of MAD2B and its downstream molecules increased after MCAO and OGD/R. Nonetheless, this expression underwent a decline post-therapy with neuroprotective agents. Deletion of MAD2B in the hippocampus ameliorated memory and learning deficits and improved motor coordination in MCAO mice. Conversely, the overexpression of MAD2B in the hippocampus exacerbated learning and memory deficits. Deletion of MAD2B resulted in the downregulation of ROCK2/LIMK1/cofilin. It effectively reduced ischemia-induced upregulation of BAX and cleaved caspase-3, which could be reversed by MAD2B overexpression. Inhibition or knockdown of ROCK2 expression in primary cultured neurons led to the downregulation of LIMK1/cofilin expression and reduced the expression of apoptosis-associated molecules induced by ischemia.

CONCLUSIONS

Our findings suggest that MAD2B affects neuronal apoptosis via Rock2, which affects neurological function and cerebral infarction.

Effects of edaravone dexborneol on functional outcome and inflammatory response in patients with acute ischemic stroke

BACKGROUND

Edaravone dexborneol has been reported as an effective neuroprotective agent in the treatment of acute ischemic stroke (AIS). This study aimed at investigating the impact of edaravone dexborneol on functional outcomes and systematic inflammatory response in AIS patient.

METHODS

All participants were recruited from the AISRNA study (registered 21/11/2019, NCT04175691 [ClinicalTrials.gov]) between January 2022 and December 2022. The AIS patients were divided into two groups based on whether they received the treatment of edaravone dexborneol (37.5 mg/12 hours, IV) within 48 h after stroke onset. Inflammatory response was determined by detecting levels of cytokines (interleukin-2 [IL-2], IL-4, IL-5, IL-8, IL-6, IL-10, IL-12p70, IL-17, tumor necrosis factor-α [TNF-α], interferon-γ [IFN-γ], IFN-α, and IL-1β) within 14 days after stroke onset.

RESULTS

Eighty-five AIS patients were included from the AISRNA study. Patients treated with edaravone dexborneol showed a significantly higher proportion of modified Rankin Scale score < 2 compared to those who did not receive this treatment (70.7% versus 47.8%; P = 0.031). Furthermore, individuals receiving edaravone dexborneol injection exhibited lower expression levels of interleukin (IL)-1β, IL-6, and IL-17, along with higher levels of IL-4 and IL-10 expression during the acute phase of ischemic stroke (P < 0.05). These trends were not observed for IL-2, IL-5, IL-8, IL-12p70, tumor necrosis factor-α, interferon-γ [IFN-γ], and IFN-α (P > 0.05).

CONCLUSIONS

Treatment with edaravone dexborneol resulted in a favorable functional outcome at 90 days post-stroke onset when compared to patients without this intervention; it also suppressed proinflammatory factors expression while increasing anti-inflammatory factors levels.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04175691. Registered November 21, 2019, https://www.

CLINICALTRIALS

gov/ct2/show/NCT04175691 .

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.

Mitochondria: A Promising Convergent Target for the Treatment of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by the progressive loss of motor neurons, for which current treatment options are limited. Recent studies have shed light on the role of mitochondria in ALS pathogenesis, making them an attractive therapeutic intervention target. This review contains a very comprehensive critical description of the involvement of mitochondria and mitochondria-mediated mechanisms in ALS. The review covers several key areas related to mitochondria in ALS, including impaired mitochondrial function, mitochondrial bioenergetics, reactive oxygen species, metabolic processes and energy metabolism, mitochondrial dynamics, turnover, autophagy and mitophagy, impaired mitochondrial transport, and apoptosis. This review also highlights preclinical and clinical studies that have investigated various mitochondria-targeted therapies for ALS treatment. These include strategies to improve mitochondrial function, such as the use of dichloroacetate, ketogenic and high-fat diets, acetyl-carnitine, and mitochondria-targeted antioxidants. Additionally, antiapoptotic agents, like the mPTP-targeting agents minocycline and rasagiline, are discussed. The paper aims to contribute to the identification of effective mitochondria-targeted therapies for ALS treatment by synthesizing the current understanding of the role of mitochondria in ALS pathogenesis and reviewing potential convergent therapeutic interventions. The complex interplay between mitochondria and the pathogenic mechanisms of ALS holds promise for the development of novel treatment strategies to combat this devastating disease.

Edaravone Dexborneol Versus Edaravone Alone for the Treatment of Acute Ischemic Stroke: A Phase III, Randomized, Double-Blind, Comparative Trial

BACKGROUND AND PURPOSE

Edaravone dexborneol, comprised of 2 active ingredients, edaravone and (+)-borneol, has been developed as a novel neuroprotective agent with synergistic effects of antioxidant and anti-inflammatory in animal models. The present clinical trial aimed at testing the effects of edaravone dexborneol versus edaravone on 90-day functional outcome in patients with acute ischemic stroke (AIS).

METHODS

A multicenter, randomized, double-blind, comparative, phase III clinical trial was conducted at 48 hospitals in China between May 2015 and December 2016. Inclusion criteria included patients diagnosed as AIS, 35 to 80 years of age, National Institutes of Health Stroke Scale Score between 4 and 24, and within 48 hours of AIS onset. AIS patients were randomized in 1:1 ratio into 2 treatment arms: 14-day infusion of edaravone dexborneol or edaravone injection. The primary end point was the proportion of patients with modified Rankin Scale score ≤1 on day 90 after randomization.

RESULTS

One thousand one hundred sixty-five AIS patients were randomly allocated to the edaravone dexborneol group (n=585) or the edaravone group (n=580). The edaravone dexborneol group showed significantly higher proportion of patients experiencing good functional outcomes on day 90 after randomization, compared with the edaravone group (modified Rankin Scale score ≤1, 67.18% versus 58.97%; odds ratio, 1.42 [95% CI, 1.12-1.81]; P=0.004). The prespecified subgroup analyses indicated that a greater benefit was observed in female patients than their male counterparts (2.26, 1.49-3.43 versus 1.14, 0.85-1.52).

CONCLUSIONS

When edaravone dexborneol versus edaravone was administered within 48 hours after AIS, 90-day good functional outcomes favored the edaravone dexborneol group, especially in female patients. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02430350.

Oxidative Stress in Amyotrophic Lateral Sclerosis: Pathophysiology and Opportunities for Pharmacological Intervention

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease or Charcot disease, is a fatal neurodegenerative disease that affects motor neurons (MNs) and leads to death within 2–5 years of diagnosis, without any effective therapy available. Although the pathological mechanisms leading to ALS are still unknown, a wealth of evidence indicates that an excessive reactive oxygen species (ROS) production associated with an inefficient antioxidant defense represents an important pathological feature in ALS. Substantial evidence indicates that oxidative stress (OS) is implicated in the loss of MNs and in mitochondrial dysfunction, contributing decisively to neurodegeneration in ALS. Although the modulation of OS represents a promising approach to protect MNs from degeneration, the fact that several antioxidants with beneficial effects in animal models failed to show any therapeutic benefit in patients raises several questions that should be analyzed. Using specific queries for literature search on PubMed, we review here the role of OS-related mechanisms in ALS, including the involvement of altered mitochondrial function with repercussions in neurodegeneration. We also describe antioxidant compounds that have been mostly tested in preclinical and clinical trials of ALS, also describing their respective mechanisms of action. While the description of OS mechanism in the different mutations identified in ALS has as principal objective to clarify the contribution of OS in ALS, the description of positive and negative outcomes for each antioxidant is aimed at paving the way for novel opportunities for intervention. In conclusion, although antioxidant strategies represent a very promising approach to slow the progression of the disease, it is of utmost need to invest on the characterization of OS profiles representative of each subtype of patient, in order to develop personalized therapies, allowing to understand the characteristics of antioxidants that have beneficial effects on different subtypes of patients.

Efficacy and safety of edaravone for acute intracerebral haemorrhage: protocol for a systematic review and meta-analysis

INTRODUCTION

Intracerebral haemorrhage (ICH) is a life-threatening condition with no effective internal treatment options. However, edaravone is a promising therapeutic agent, although its beneficial effects are inconclusive based on previous systematic reviews and meta-analyses. While several trials in the last 8 years have reported the favourable long-term functional outcomes, a few reports indicated edaravone to be associated with an increase in adverse events.

METHODS AND ANALYSIS

This protocol was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. We will perform the comprehensive and manual search for published articles, ongoing trials, dissertations and grey literature. The following databases will be searched from inception to 23 April 2020: Medline, Embase, the Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, Chinese scientific periodical database of VIP INFORMATION, Wanfang Data and SinoMed, with no language restrictions. All randomised controlled trials that (1) compared edaravone with placebo or no treatment, and (2) compared edaravone plus routine treatment or cointervention with routine treatment or cointervention for treating acute ICH will be included. Mortality and long-term dependency will be the primary outcomes. The incidence of adverse events will be assessed for safety evaluation. Two reviewers in pairs will independently carry out the article selection, data extraction and quality assessment. Assessment of the risk of bias and data synthesis will be performed using software Review Manager V.5.3. Finally, we will use the Grading of Recommendations Assessment, Development and Evaluation approach to evaluate the quality of the overall evidence.

ETHICS AND DISSEMINATION

There are no ethical considerations associated with this updated systematic review and meta-analysis. The findings will be disseminated in peer-reviewed journals or conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42019147801.

Clinical Effects of Early Edaravone Use in Acute Ischemic Stroke Patients Treated by Endovascular Reperfusion Therapy

Background and Purpose- Although several clinical studies suggested the beneficial effects of edaravone in acute ischemic stroke, most were performed under settings that differ from those in the current treatment strategy, which has dramatically changed with progress in reperfusion therapies. This study aimed to evaluate the efficacy of edaravone in patients with acute ischemic stroke treated by emergent endovascular reperfusion therapy. Methods- We conducted a retrospective observational study using a national administrative database. Patients with acute ischemic stroke treated by emergent endovascular reperfusion therapy were identified and dichotomized by whether edaravone was used within 2 days of admission. We compared the functional independence at hospital discharge, in-hospital mortality, and intracranial hemorrhage after admission between groups, adjusted by a well-validated case-mix adjustment model, in multivariate mixed-effect regression and propensity score matching analyses. Results- Of 11 508 patients eligible for analysis, 10 281 (89.3%) received edaravone therapy. The established risk adjustment model had good predictability for functional independence at hospital discharge, with an area under the receiver operating characteristic curve of 0.74. In the mixed-effect regression analysis, edaravone use was significantly associated with greater functional independence at hospital discharge (32.3% in the edaravone group versus 25.9% in the control group; adjusted odds ratio, 1.21; 95% confidence interval, 1.03-1.41), lower in-hospital mortality (9.9% in the edaravone group versus 17.4% in the control group; adjusted odds ratio, 0.52; 95% confidence interval, 0.43-0.62), and reduced intracranial hemorrhage after admission (1.4% in the edaravone group versus 2.7% in the control group; adjusted odds ratio, 0.55; 95% confidence interval, 0.37-0.82). Results of the propensity score matching analysis corroborated these results. Conclusions- This retrospective analysis of a Japanese nationwide administrative database suggested that combination therapy with edaravone and endovascular reperfusion therapy could be a promising therapeutic strategy in acute ischemic stroke. Further randomized control trials are warranted.

Safety and efficacy of Edaravone Dexborneol versus edaravone for patients with acute ischaemic stroke: a phase II, multicentre, randomised, double-blind, multiple-dose, active-controlled clinical trial

Background

Edaravone Dexborneol is a novel neuroprotective agent that comprised edaravone and (+)-borneol, a food additive with an anti-inflammatory effect in animal ischaemic stroke models. This study aims to assess the safety and efficacy of Edaravone Dexborneol compared with edaravone in treating patients with acute ischaemic stroke (AIS).

Methods

In this multicentre, randomised, double-blind, multiple-dose, active-controlled, phase II clinical trial, patients with AIS within 48 hours after stroke onset were randomly assigned (1:1:1:1) to low-dose (12.5 mg), medium-dose (37.5 mg) or high-dose (62.5 mg) Edaravone Dexborneol groups, and an active control group with edaravone (30 mg) by 30 min intravenous infusion every 12 hours, for 14 consecutive days. The primary efficacy outcome was the proportion of modified Rankin Scale (mRS)score ≤1 at 90 days and National Institutes of Health Stroke Scale (NIHSS) score change from baseline to 14 days after randomisation. The safety outcome included any adverse event during 90 days after treatment.

Results

Of 385 patients included in the efficacy analysis, 94 were randomised to low-dose group, 97 to medium-dose group, 98 to high-dose group and 96 to the control group. No significant difference was observed among the four groups on mRS score (mRS ≤1, p=0.4054) at 90 days or NIHSS score change at 14 days (p=0.6799). However, a numerically higher percentage of patients with mRSscore ≤1 at 90 days in the medium-dose (69.39%) and high-dose (65.63%) groups was observed than in the control group (60.64%). No significant difference in severe adverse events was found among the four groups (p=0.3815).

Conclusions

Compared with edaravone alone, Edaravone Dexborneol was safe and well tolerated at all doses, although no significant improvement in functional outcomes was observed at 90days.

Trial registration number

NCT01929096.

Open-label 24-week extension study of edaravone (MCI-186) in amyotrophic lateral sclerosis

We aimed to explore the longer-term efficacy and safety of edaravone in an active-treatment extension period following the double-blind period of the second phase III study. Patients who met all the following criteria (scores ≥2 points on all 12 items of the revised amyotrophic lateral sclerosis functional rating scale [ALSFRS-R], forced vital capacity ≥80%, definite or probable ALS, and disease duration ≤2 years) were randomised to 60 mg intravenous edaravone or placebo for six cycles in the double-blind period, and then offered the opportunity to proceed to this 24-week open-label extension period. One hundred and twenty-three of 137 patients continued to the extension period: 65 edaravone-edaravone (E-E group) and 58 placebo-edaravone (P-E group). Change (mean ± standard deviation; SD) in the ALSFRS-R score from baseline in the double-blind period was -4.1 ± 3.4 and -6.9 ± 5.1 in the E-E group and P-E group, respectively, while it was -8.0 ± 5.6 in the E-E group and -10.9 ± 6.9 in the P-E group over the whole 48-week period. The ALSFRS-R score changed almost linearly throughout Cycles 1-12 in the E-E group. The most commonly reported adverse events were constipation, dysphagia, and contusion. There was no sudden deterioration in the ALSFRS-R score of the E-E group. No safety concerns related to edaravone were detected.

Efficacy, safety, and outcomes in 17 pediatric cases treated with the free radical scavenger edaravone

SUBJECTS

Edaravone is a free radical scavenger with brain protection properties and is recommended by "The Japanese Guidelines for the Management of Stroke 2009" for administration to adult patients, in whom it has been shown to improve neurological deficits after cerebral infarction. However, its dosage and effects have not yet been established in children.

METHODS

Seventeen pediatric patients with cerebral ischemia were administered edaravone at a dose based on body weight from the standard dose given to adults. Functional outcomes were evaluated using mRS and PSOM (modified ranking scale and pediatric stroke outcome scale, respectively).

RESULTS

Immediate post-treatment results were mostly positive, with no liver or renal complications. In some cases, neurological symptoms markedly improved after the administration of edaravone.

CONCLUSIONS

The efficacy of edaravone has not yet been examined in pediatric patients. The results of the present study suggest that edaravone has potential in the treatment of children safely with promising results similar to those in adults.

Chemical repair activity of free radical scavenger edaravone: reduction reactions with dGMP hydroxyl radical adducts and suppression of base lesions and AP sites on irradiated plasmid DNA

Reactions of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) with deoxyguanosine monophosphate (dGMP) hydroxyl radical adducts were investigated by pulse radiolysis technique. Edaravone was found to reduce the dGMP hydroxyl radical adducts through electron transfer reactions. The rate constants of the reactions were greater than 4 × 10(8) dm(3) mol(-1) s(-1) and similar to those of the reactions of ascorbic acid, which is a representative antioxidant. Yields of single-strand breaks, base lesions, and abasic sites produced in pUC18 plasmid DNA by gamma ray irradiation in the presence of low concentrations (10-1000 μmol dm(-3)) of edaravone were also quantified, and the chemical repair activity of edaravone was estimated by a method recently developed by the authors. By comparing suppression efficiencies to the induction of each DNA lesion, it was found that base lesions and abasic sites were suppressed by the chemical repair activity of edaravone, although the suppression of single-strand breaks was not very effective. This phenomenon was attributed to the chemical repair activity of edaravone toward base lesions and abasic sites. However, the chemical repair activity of edaravone for base lesions was lower than that of ascorbic acid.

The radical scavenger edaravone improves neurologic function and perihematomal glucose metabolism after acute intracerebral hemorrhage

Oxidative injury caused by reactive oxygen species plays an important role in the progression of intracerebral hemorrhage (ICH)-induced secondary brain injury. Previous studies have demonstrated that the free radical scavenger edaravone may prevent neuronal injury and brain edema after ICH. However, the influence of edaravone on cerebral metabolism in the early stages after ICH and the underlying mechanism have not been fully investigated. In the present study, we investigated the effect of edaravone on perihematomal glucose metabolism using (18)F-fluorordeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). Additionally, the neurologic deficits, brain edemas, and cell death that followed ICH were quantitatively analyzed. After blood infusion, the rats treated with edaravone showed significant improvement in both forelimb placing and corner turn tests compared with those treated with vehicle. Moreover, the brain water content of the edaravone-treated group was significantly decreased compared with that of the vehicle group on day 3 after ICH. PET/CT images of ICH rats exhibited obvious decreases in FDG standardized uptake values in perihematomal region on day 3, and the lesion-to-normal ratio of the edaravone-treated ICH rats was significantly increased compared with that of the control rats. Calculation of the brain injury volumes from the PET/CT images revealed that the volumes of the blood-induced injuries were significantly smaller in the edaravone group compared with the vehicle group. Terminal Deoxynucleotidyl Transferase-mediated dUTP Nick End Labeling assays performed 3 days after ICH revealed that the numbers of apoptotic cells in perihematomal region of edaravone-treated ICH rats were decreased relative to the vehicle group. Thus, the present study demonstrates that edaravone has scavenging properties that attenuate neurologic behavioral deficits and brain edema in the early period of ICH. Additionally, edaravone may improve cerebral metabolism around the hematoma by attenuating apoptotic cell death after ICH.

Simultaneous administration of recombinant tissue plasminogen activator and edaravone in acute cerebral ischemic stroke patients

Among the 1052 patients admitted to our hospital because of cerebral infarction between January 1, 2007, and December 31, 2010, we report the treatment outcomes of 48 patients (4.6% of all patients) who received recombinant tissue plasminogen activator (rt-PA) therapy (simultaneously combined with edaravone) within 3 hours after the onset of infarction. Twenty (41.7%) patients started receiving edaravone before rt-PA administration, and 28 patients (58.3%) started receiving rt-PA and edaravone simultaneously. The patients had an average age of 73.5 years (range, 55-93 years; male:female, 32:16). Medical histories included hypertension, diabetes mellitus, dyslipidemia, arterial fibrillation, and a smoking history in 23 (47.8%), 7 (14.6%), 8 (16.7%), 29 (60.4%), and 8 (16.7%) of patients, respectively. Regarding the treatment outcome of the therapy, the National Institutes of Health Stroke Scale score, which was 15 points before rt-PA administration, showed a statistically significant improvement to 8 points after rt-PA administration (P < .001). The modified Rankin Scale scores at 90 days after treatment were as follows: 0 in 12 patients (25.0%), 1 in 11 patients (22.9%), 2 in 7 patients (14.6%), 3 in 5 patients (10.4%), 4 in 6 patients (12.5%), 5 in 5 patients (10.4%), and 6 in 2 patients (4.2%). The occluded blood vessel reopened completely in 30 patients (62.5%) and partially in 5 patients (10.4%). Asymptomatic hemorrhage over the entire brain developed in 2 patients (4.2%). Thus, rt-PA therapy in combination with edaravone improved the recanalization rate, reduced the incidence of intracranial hemorrhage, and improved functional prognosis.

Edaravone ameliorates the adverse effects of valproic acid toxicity in small intestine

Valproic acid (VPA) is a drug used for the treatment of epilepsy, bipolar psychiatric disorders, and migraine. Previous studies have reported an increased generation of reactive oxygen species and oxidative stress in the toxic mechanism of VPA. Edaravone, a free radical scavenger for clinical use, can quench free radical reaction by trapping a variety of free radical species. In this study, effect of edaravone on some small intestine biochemical parameters in VPA-induced toxicity was investigated. Thirty seven Sprague Dawley female rats were randomly divided into four groups. The groups include control group, edaravone (30 mg–1 kg–1 day–1) given group, VPA (0.5 g–1 kg–1 day–1) given group, VPA + edaravone (in same dose) given group. Edaravone and VPA were given intraperitoneally for 7 days. Biochemical parameters such as malondialdehyde, as an index of lipid peroxidation(LPO), sialic acid (SA), glutathione levels and glutathione peroxidase, glutathione- S-transferase, superoxide dismutase, catalase, myeloperoxidase, alkaline phosphatase (ALP), and tissue factor (TF) activities were determined in small intestine samples by colorimetric methods. Decreased small intestine antioxidant enzyme activities, increased LPO and SA levels, and increased activities of ALP and TF were detected in the VPA group. Based on our results edaravone may be suggested to reverse the oxidative stress and inflammation due to VPA-induced small intestine toxicity.

Confirmatory double-blind, parallel-group, placebo-controlled study of efficacy and safety of edaravone (MCI-186) in amyotrophic lateral sclerosis patients

Our objective was to confirm the efficacy and safety of edaravone in amyotrophic lateral sclerosis (ALS) patients. We conducted a 36-week confirmatory study, consisting of 12-week pre-observation period followed by 24-week treatment period. Patients received placebo or edaravone i.v. infusion over 60 min for the first 14 days in cycle 1, and for 10 of the first 14 days during cycles 2 to 6. The efficacy primary endpoint was changed in the revised ALS functional rating scale (ALSFRS-R) scores during the 24-week treatment. Patients were treated with placebo (n = 104) and edaravone (n = 102). Changes in ALSFRS-R during the 24-week treatment were -6.35 ± 0.84 in the placebo group (n = 99) and -5.70 ± 0.85 in the edaravone group (n = 100), with a difference of 0.65 ± 0.78 (p = 0.411). Adverse events amounted to 88.5% (92/104) in the placebo group and 89.2% (91/102) in the edaravone group. In conclusion, the reduction of ALSFRS-R was smaller in the edaravone group than in the placebo group, but efficacy of edaravone for treatment of ALS was not demonstrated. Levels and frequencies of reported adverse events were similar in the two groups.

Ginsenoside Rd for acute ischemic stroke: translating from bench to bedside

Numerous studies have identified pathophysiological mechanisms of acute ischemic stroke and have provided proof-of-principle evidence that strategies designed to impede the ischemic cascade, namely neuroprotection, can protect the ischemic brain. However, the translation of these therapeutic agents to the clinic has not been successful. Ginsenoside Rd, a dammarane-type steroid glycoside extracted from ginseng plants, has exhibited an encouraging neuroprotective efficacy in both laboratory and clinical studies. This article attempts to provide a synopsis of the physiochemical profile, pharmacokinetics, pharmacodynamics, clinical efficacy, safety and putative therapeutic mechanisms of Rd. Finally, the authors discuss the validity of Rd as a neuroprotective agent for acute ischemic stroke.

Safety, tolerability and pharmacokinetics of MCI-186 in patients with acute ischemic stroke: new formulation and dosing regimen

BACKGROUND AND PURPOSE

MCI-186 (edaravone) is a free radical scavenger approved in Japan since 2001 for the treatment of patients with acute ischemic stroke within 24 h from the onset of symptoms. It was recommended by the Japanese Guidelines for the Management of Stroke 2004. Our aim was to investigate the safety, tolerability and pharmacokinetics of a new formulation and dose regimen (intravenous bolus plus infusion) of MCI-186 suitable for the treatment of acute ischemic stroke in Europe because the Japanese treatment protocol includes twice-a-day intravenous infusion of MCI-186 for a maximum of 14 days. Such a treatment protocol is not very practical in Europe, where hospital stay is much shorter in acute hospitals.

METHODS

In a double-blind, placebo-controlled randomized clinical trial we studied two dosing regimens, each in a cohort of 18 patients. Patients were randomized in a 2:1 ratio in both cohorts to receive MCI-186 or placebo. Review of safety and plasma concentration data from the first cohort (loading dose 0.08 mg/kg + 0.2 mg/kg/h infusion) preceded the second cohort (loading dose 0.16 mg/kg + 0.4 mg/kg/h infusion). Safety parameters included adverse events, severe adverse events, physical examinations, local reactions at infusion site, ECG, clinical chemistry and hematology, modified Total Neuropathy Score and CT scans.

RESULTS

Mean age and National Institutes of Health Stroke Scale (NIHSS) score on admission of patients in cohorts 1 and 2 and the placebo group were 64, 63, and 69 years and 5, 5, and 6, respectively. The number of treatment emergent adverse events that occurred was 109, most of which were transient, mild or moderate. Both doses of the new formulation and dosing regimen were well tolerated. After the initiation of the infusion, plasma concentrations of MCI-186 reached or exceeded prespecified target levels within 24 h in both MCI-186 cohorts, which were in the putative therapeutic range in humans. Geometric mean values of MCI-186 plasma concentration at the end of the infusion in cohorts 1 and 2 were 391 and 1,595 ng/ml, respectively.

CONCLUSIONS

The primary objective of the present study, safety and tolerability of the new formulation and dosing regimen, was achieved. The new formula and both dosing regimens were well tolerated and achieved intended plasma concentrations suitable for larger safety studies before pivotal trials.

Novel effects of edaravone on human brain microvascular endothelial cells revealed by a proteomic approach

Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a free radical scavenger used for acute ischemic stroke. However, it is not known whether edaravone works only as a free radical scavenger or possess other pharmacological actions. Therefore, we elucidated the effects of edaravone on human brain microvascular endothelial cells (HBMECs) by 2 dimensional fluorescence difference gel electrophoresis (2D-DIGE). We found 38 protein spots the intensity of which was significantly altered 1.3 fold on average (p< 0.05) by the edaravone treatment and successfully identified 17 proteins of those. Four of those 17 proteins were cytoskeleton proteins or cytoskeleton-regulating proteins. Therefore, we subsequently investigated the change of size and shape of the cells, the actin network, and the tight junction of HBMEC by immunocytochemistry. As a result, most edaravone-treated HBMECs became larger and rounder compared with those that were not treated. Furthermore, edaravone-treated HBMECs formed gathering zona occludens (ZO)-1, a tight junction protein, along the junction of the cells. In addition, we found that edaravone suppressed interleukin (IL)-1β-induced secretion of monocyte chemoattractant protein-1 (MCP-1), which was reported to increase cell permeability. We found a novel function of edaravone is the promotion of tight junction formations of vascular endothelial cells partly via the down-regulation of MCP-1 secretion. These data provide fundamental and useful information in the clinical use of edaravone in patients with cerebral vascular diseases.

In vivo and in vitro treatment with edaravone promotes proliferation of neural progenitor cells generated following neuronal loss in the mouse dentate gyrus

Edaravone is clinically used in Japan for treatment of patients with acute cerebral infarction. To clarify the effect of edaravone on neurogenesis in the hippocampus following neuronal injury in the hippocampal dentate gyrus, we investigated the effect of in vitro and in vivo treatment with edaravone on the proliferation of neural stem/progenitor cells prepared from the mouse dentate gyrus damaged by trimethyltin (TMT). Histological assessment revealed the presence of large number of nestin(+) cells in the dentate gyrus on days 3 - 5 post-TMT treatment. We prepared cells from the dentate gyrus of naïve, TMT-treated mice or TMT/edaravone-treated mice. The cells obtained from the dentate gyrus of TMT-treated animals were capable of BrdU incorporation and neurosphere formation when cultured in the presence of growth factors. The TMT-treated group had a larger number of nestin(+) cells and nestin(+)GFAP(+) cells than the naïve one. Under the culture condition used, sustained exposure of the cells from the damaged dentate gyrus to edaravone at 10(-11) and 10(-8) M promoted the proliferation of nestin(+) cells. The systemic in vivo treatment with edaravone for 2 days produced a significant increase in the number of nestin(+) cells among the cells prepared from the dentate gyrus on day 4 post-TMT treatment, and as well as one in the number of neurospheres formed from these cells in the culture. Taken together, our data indicated that edaravone had the ability to promote the proliferation of neural stem/progenitor cells generated following neuronal damage in the dentate gyrus.

Density functional theory (DFT) study of edaravone derivatives as antioxidants

Quantum chemical calculations at the B3LYP/6–31G* level of theory were employed for the structure-activity relationship and prediction of the antioxidant activity of edaravone and structurally related derivatives using energy (E), ionization potential (IP), bond dissociation energy (BDE), and stabilization energies (ΔE_iso). Spin density calculations were also performed for the proposed antioxidant activity mechanism. The electron abstraction is related to electron-donating groups (EDG) at position 3, decreasing the IP when compared to substitution at position 4. The hydrogen abstraction is related to electron-withdrawing groups (EDG) at position 4, decreasing the BDE_CH when compared to other substitutions, resulting in a better antioxidant activity. The unpaired electron formed by the hydrogen abstraction from the C–H group of the pyrazole ring is localized at 2, 4, and 6 positions. The highest scavenging activity prediction is related to the lowest contribution at the carbon atom. The likely mechanism is related to hydrogen transfer. It was found that antioxidant activity depends on the presence of EDG at the C₂ and C₄ positions and there is a correlation between IP and BDE. Our results identified three different classes of new derivatives more potent than edaravone.

Protective Effects of Total Flavones of Rhododendra on Cerebral Ischemia Reperfusion Injury

This study was to investigate the protective effects and possible mechanisms of total flavones of rhododendra (TFR) against cerebral ischemia reperfusion injury in rats and mice. Cerebral ischemia/reperfusion injury was induced by occluding the right middle cerebral artery (MCA). Infarct volume, neurological deficit, brain water content, levels of malondialdehyde (MDA), nitric oxide (NO) contents, lactate dehydrogenase (LDH) activity in plasma and brain, levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and mRNA expression of inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS) in brain were evaluated 7 or 10 days after treatment. TFR significantly reduced infarct volume, ameliorated the neurological deficit and reduced the brain water content. The activities of SOD, LDH and GPX in brain were enhanced, while the activity of LDH in plasma and the contents of MDA and NO in plasma and brain were decreased. While, the expression of iNOS and nNOS mRNA in brain were down-regulated, the expression of eNOS mRNA in the brain was up-regulated. These results suggest that TFR has protective effects for cerebral injury in rats and mice, which might be associated with its antioxidant properties and ability to regulate the expression of NOS isoforms.

Injectable Caltrop Fruit Saponin Protects Against Ischemia-Reperfusion Injury in Rat Brain

The present study aimed to investigate the protective effects of injectable caltrop fruit saponin preparation (ICFSP) on ischemia-reperfusion injury in rat brain. Rats were injected with ICFSP and then subjected to cerebral ischemia-reperfusion injury induced by middle cerebral artery occlusion. Then the neurological deficit score was evaluated by Bederson's method. The infarct size was assessed by TTC staining. The content of malondialdehyde (MDA) and nitric oxide (NO), and the activity of superoxide dismutase (SOD) in rat cerebrum were measured with kits, and the content of 6 K prostaglandin F1α (6-K-PGF 1α), thromboxane B2 (TXB2) and endothelin (ET) in blood plasma was measured by radioimmunoassay. The results demonstrated that ICFSP led to a decrease in infarct size (p < 0.01), neurological deficit score (p < 0.05) and plasma content of TXB2 and ET (p < 0.05), and an increase of the plasma level of 6-K-PGF 1α (p < 0.05) and SOD activity in cerebrum, where the MDA and NO content were decreased. The treatment improved forelimb function. ICFSP showed a similar potency compared to that of Ligustrazine hydrochloride parenteral solution (LHPS) and nimodipine (Nim). We concluded that ICFSP protects the brain damage caused by ischemia-reperfusion injury in rats, and this may be closely related to the regulation of reactive oxygen species (MDA and SOD activity) and NO levels in the rat cerebrum, as well as vasoactive factors in the plasma (6-K-PGF 1α, TXB2 and ET).

Protective effects of Galla Rhois, the excrescence produced by the sumac aphid, Schlechtendalia chinensis, on transient focal cerebral ischemia in the rat

Galla Rhois is formed by aphids, primarily Schlechtendalia chinensis Bell (Homoptera: Pemphigidae), on the leaf of sumac, Rhus javanica L. (Sapindales: Anacardiaceae). It is a tannin-rich herb that is widely used in traditional Korean medicine. Its various pharmacological effects, including its radical-scavenging effects, have been reported. The purpose of the current study was to determine if these radical-scavenging effects can be confirmed using in vitro assays and to investigate its neuroprotective effects, optimal dosage, mechanisms, and therapeutic time window in an animal model of stroke. Galla Rhois 85% methanol extract (GRE) exhibited potent and dose-dependent radical-scavenging effects on various radicals. Oral administration of GRE (300 mg/kg) in a transient focal cerebral ischemia rat model (two hours of occlusion followed by 22 hours of reperfusion) reduced the brain infarct volume by 37.5%. It also improved sensory motor function and reduced lipid-peroxidation in middle cerebral artery occlusion. However, it did not have any inhibitory effects on brain edema. The time window study revealed that pre- and co-treatment with GRE had protective effects, but post-treatment with GRE (three or six hours after ischemia) did not have protective effects. In conclusion, GRE had potent radical-scavenging activities and neuroprotective effects in a rat model of stroke when it was pre- and co-administered. The optimal dosage may be around 300 mg/kg for oral administration.

Edaravone, a free radical scavenger, attenuates behavioral deficits following transient forebrain ischemia by inhibiting oxidative damage in gerbils

The present study investigates the neurological protective effects of edaravone against global brain ischemia. Gerbils were treated with edaravone (3mg/kg; i.p.) 30min before transient forebrain ischemia, which was induced by occluding the bilateral common carotid artery for 5min. The effects of edaravone were examined by measuring neuronal damage and behavioral deficits. Hexanoyl-lysine adduct (HEL) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), oxidative stress markers, were also examined to assess the anti-oxidative effects of edaravone. Edaravone treatment significantly inhibited both lipid and DNA oxidative damage 72h after ischemia, and decreased neuronal damage. Edaravone also significantly reduced the locomotor activity deficit 72h after ischemia and improved memory impairment. These findings suggest that edaravone inhibits oxidative stress and attenuates neuronal damage induced by transient forebrain ischemia in gerbils and which may contribute to improvements in behavioral deficits.

Clinical evaluation of liver injury in patients with acute ischemic brain stroke treated with edaravone

AIM

  To elucidate the etiologic factors and features of liver injury in patients with acute ischemic brain stroke who were treated with edaravone and reported by their attending physicians to have developed serious liver injury.

METHODS

  The present study investigated 123 patients with a verified episode of liver injury among 132 patients with serious liver injury that had been reported attributable to edaravone.

RESULTS

  Ischemic and/or congestive liver (70.7%) were most predominant among the etiologic factors for liver injury, and edaravone-related liver injury accounted for 20.3% (25 patients). Evident liver injury (defined in the text) was found in 104 among 123 evaluated patients; 54 patients (51.9%) of the former subset showed severe liver injury (defined increases in serum aspartate and/or alanine aminotransferase levels of ≥1000 IU/L and/or serum total bilirubin levels of ≥5 mg/dL). Among 104 patients with evident liver injury, 65 showed recovery. Furthermore, 53 patients (51.0%) were complicated by renal disorders; all of these patients had ischemic and/or congestive liver, or severe infections.

CONCLUSIONS

  Edaravone was considered to be etiologic for liver injury in approximately 20% of evaluated patients. When a patient treated with edaravone developed liver injury therefore an investigation not only on edaravone but also on other potential etiologic factors (e.g. ischemic liver, congestive liver, and infection) and the quick implementation of appropriate treatments, especially for infections, revealed possible reductions in the incidences of severe liver injury and of complications by renal disorders.

Pulse radiolysis study on free radical scavenger edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one). 2: A comparative study on edaravone derivatives

A comparative study using the pulse radiolysis technique was carried out to investigate transient absorption spectra and rate constants for the reactions of (•)OH and N(3)(•) with edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) and its four analogue compounds, 1,3-dimethyl-2-pyrazolin-5-one, 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one, 1-phenyl-3-trifluoromethyl-2-pyrazolin-5-one and 1-(4-chlorophenyl)-3-methyl-2-pyrazolin-5-one. The results showed that, unlike reaction mechanisms previously proposed, the phenyl group of edaravone played an important role in the reaction with (•)OH and OH adducts to the phenyl group were formed. Quantum chemical calculations also strongly supported this attribution and suggested that the most favorable site for attacks by (•)OH is the ortho position of the phenyl group. Moreover, the rate constants for the reactions of edaravone and its analogues towards (•)OH and N(3)(•) were about 8.0 × 10(9), and 4.0 × 10(9) dm(3) mol(-1) s(-1), respectively. Edaravone displayed higher reactivity compared to the others, in contrast to a previous report in which 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one showed the highest reactivity towards (•)OH.

Systemic administration of a free radical scavenger, edaravone, protects against light-induced photoreceptor degeneration in the mouse retina

Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a free radical scavenger, is used for the clinical treatment of acute cerebral infarction. In this study, we investigated the protective effects of edaravone against light-induced retinal damage in the mouse. Retinal damage in the mouse was induced by exposure to white light at 8000lx for 3h after dark adaptation. Photoreceptor damage was evaluated by measuring the outer nuclear layer thickness at 5days after the light exposure and recording the electroretinogram (ERG). Retinal cell damage was also detected by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, and the expression of 8-hydroxy-2-deoxyguanosine (8-OHdG) and the phosphorylation of mitogen-activated protein kinases (MAPKs) such as extracellular signal regulated protein kinases (ERK), c-Jun N-terminal kinases (JNK), and p38 were analyzed in the retinal samples by immunohistochemistry and immunoblotting. According to evaluation of outer nuclear layer thickness, 3mg/kg, i.p. of edaravone and 1mg/kg. i.v. of edaravone significantly protected against light-induced photoreceptor degeneration at 5days after exposure to light. In ERG measurement, 3mg/kg, i.p. of edaravone inhibited retinal dysfunction at 5days after exposure to light. In addition, 3mg/kg, i.p. of edaravone decreased the numbers of TUNEL-positive cells, 8-OHdG, phosphorylated JNK, and phosphorylated p38, but not that of phosphorylated ERK, in the whole retina at 6h after light exposure. These findings suggest that oxidative stress plays a pivotal role in light-induced retinal damage and that systemic administration of edaravone may slow the progression of photoreceptor degeneration.

Pharmacokinetic interaction between puerarin and edaravone, and effect of borneol on the brain distribution kinetics of puerarin in rats

Objectives

The aim was to investigate the pharmacokinetic interaction between puerarin and edaravone, and the effect of borneol on the brain distribution kinetics of puerarin in rats.

Methods

A reversed-phase high performance liquid chromatography method was developed and validated for the simultaneous determination of puerarin and edaravone in rat plasma. The detection method was successfully applied to compare the pharmacokinetic interaction and brain distribution kinetics of puerarin and edaravone using in-situ microdialysis sampling in rats after intravenous administration and co-administration with a single dose.

Key findings

The method gave good linearity and no endogenous material interfered with the two target compounds and internal standard peaks. The limit of detection of puerarin and edaravone was 0.03 and 0.05 μg/ml, respectively. The average recovery of the two compounds from rat plasma was &gt;94%. The precision of the test was determined to be within 10%. The combination of puerarin and edaravone reduced drug elimination rates, gave a wider distribution, and the disposition of both drugs in rats was optimized. The distribution of puerarin in brain tissues was significantly increased and its elimination was noticeably slower with borneol pretreatment.

Conclusions

The results provide important information for the improved combined use of puerarin and edaravone with borneol pretreatment in clinical practice.

Changes of expression of glucose transporters in the fetal lamb brain after MCI-186 administration to the maternal circulation with 10-min persistent umbilical cord occlusion

OBJECTIVE

To evaluate the effect of MCI-186 (3-methyl-1-phenyl-2-pyrazoline-5-one), a potent hydroxyl radical scavenger, administered to the maternal circulation following umbilical cord occlusion in regard to glucose transporter (GLUT) expression.

MATERIALS AND METHODS

Fourteen instrumented lambs were prepared. In three cases, a 10-min persistent umbilical cord occlusion was performed; 30 min after the insult, fetal brains were extirpated (Group A). Four cases had a 10-min occlusion(Group B) and four cases had 10-min occlusion and were administered MCI-186 to the maternal circulation (Group C).Three days following the insult, the fetal brains were extirpated. The remaining three cases had a sham operation (Group D).Brain tissue sections were stained at the locations of GLUT-1, -3 and -5 and were evaluated by two pathologists.

RESULTS

The expression of GLUT-1 and -3 significantly increased in the basal ganglia, hippocampi and periventricular region of Group B when compared with that of Group A. The expression of GLUT-1 and -3 in three regions of Group B were significantly higher than that of Group C and D. GLUT-5 was recognised only in Group B.

CONCLUSION

On the basis of expression of GLUT, the protective effect of MCI-186 on brain injury resulting from hypoxia/ ischemia-reperfusion is documented.

Edaravone protects against apoptotic neuronal cell death and improves cerebral function after traumatic brain injury in rats

Edaravone is a novel free radical scavenger used clinically in patients with acute cerebral infarction; however, it has not been assessed in traumatic brain injury (TBI). We investigated the effects of edaravone on cerebral function and morphology following TBI. Rats received TBI with a pneumatic controlled injury device. Edaravone (3 mg/kg) or physiological saline was administered intravenously following TBI. Numbers of 8-OHdG-, 4-HNE-, and ssDNA-positive cells around the damaged area after TBI were significantly decreased in the edaravone group compared with the saline group (P < 0.01). There was a significant increase in neuronal cell number and improvement in cerebral dysfunction after TBI in the edaravone group compared with the saline group (P < 0.01). Edaravone administration following TBI inhibited free radical-induced neuronal degeneration and apoptotic cell death around the damaged area. In summary, edaravone treatment improved cerebral dysfunction following TBI, suggesting its potential as an effective clinical therapy.

Protective effects of edaravone against cobalt chloride-induced apoptosis in PC12 cells

OBJECTIVE

To investigate the neuroprotective effects of edaravone (Eda) on cobalt chloride (CoCl2)-induced oxidative stress and apoptosis in cultured PC12 cells as well as the underlying mechanisms.

METHODS

PC12 cells impaired by CoCl2 were used as the cell model of hypoxia. MTT (methyl thiazolyl tetrazolium) was used to assay the viability of the PC12 cells exposed to Eda with gradient concentrations; Hochest 33258 stain assay was used to analyze the apoptosis ratio of the PC12 cells; Bcl-2 and Bax protein levels in PC12 cells were examined by western blotting. ROS level, the mitochondrial transmembrane potential and caspase-3 activity in each group were detected by spectrofluorometer.

RESULTS

CoCl2 treatment caused the loss of cell viability in PC12 cells, which was associated with the elevation of apoptotic rate, the formation of ROS and the disruption of mitochondrial transmembrane potential. CoCl2 also significantly induced the upregulation of Bax/Bcl-2 ratio and the activation of caspase-3. In contrast, Eda significantly reversed these phenotypes, with its maximum protective effect at 0.1 micromol/L.

CONCLUSION

These results indicated that Eda could protect PC12 cells from CoCl2-induced cytotoxicity, and this protection might be ascribed to its anti-oxidative and anti-apoptotic activities.

The novel free radical scavenger, edaravone, increases neural stem cell number around the area of damage following rat traumatic brain injury

Edaravone is a novel free radical scavenger that is clinically employed in patients with acute cerebral infarction, but has not previously been used to treat traumatic brain injury (TBI). In this study, we investigated the effect of edaravone administration on rat TBI. In particular, we used immunohistochemistry to monitor neural stem cell (NSC) proliferation around the area damaged by TBI. Two separate groups of rats were administered saline or edaravone (3 mg/kg) after TBI and then killed chronologically. We also used ex vivo techniques to isolate NSCs from the damaged region and observed nestin-positive cells at 1, 3, and 7 days following TBI in both saline- and edaravone-treated groups. At 3 days following TBI in both groups, there were many large cells that morphologically resembled astrocytes. At 1 and 7 days following TBI in the saline group, there were a few small nestin-positive cells. However, in the edaravone group, there were many large nestin-positive cells at 7 days following TBI. At 3 and 7 days following TBI, the number of nestin-positive cells in the edaravone group increased significantly compared with the saline group. There were many single-stranded DNA-, 8-hydroxy-2'-deoxyguanosine-, and 4-hydroxy-2-nonenal-positive cells in the saline group following TBI, but only a few such cells in the edaravone group following TBI. Furthermore, almost all ssDNA-positive cells in the saline group co-localized with Hu, nestin, and glial fibrillary acidic protein (GFAP) staining, but not in the edaravone group. In the ex vivo study, spheres could only be isolated from injured brain tissue in the saline group at 3 days following TBI. However, in the edaravone group, spheres could be isolated from injured brain tissue at both 3 and 7 days following TBI. The number of spheres isolated from injured brain tissue in the edaravone group showed a significant increase compared with the saline group. The spheres isolated from both saline and edaravone groups were immunopositive for nestin, but not Tuj1 or vimentin. Moreover, the spheres differentiated into Tuj1-, GFAP-, and O4-positive cells after 4 days in culture without bFGF. This result indicated that the spheres were neurospheres composed of NSCs that could differentiate into neurons and glia. Edaravone administration inhibited production of free radicals known to induce neuronal degeneration and cell death after brain injury, and protected nestin-positive cells, including NSCs, with the potential to differentiate into neurons and glia around the area damaged by TBI.

MCI-186 administered to the maternal circulation inhibits fetal brain injury resulting from total umbilical cord occlusion in the chronically instrumented fetal lamb

OBJECTIVE

To evaluate the transplacental effects of MCI-186 (edaravone), a potent hydroxyl radical scavenger, administered to the maternal circulation to inhibit fetal brain injury caused by umbilical cord occlusion.

METHODS

Nine chronically instrumented lambs were prepared. In three cases, 10-min persistent total umbilical cord occlusion (group A) was performed. Another three cases underwent occlusion and were administered 60 mg of MCI-186 through the maternal femoral vein prior to the end of occlusion (group B). The remaining three cases underwent sham operation (group C). On day 3 after insult, fetal brains were extirpated. Paraffin-embedded brain tissue sections were stained with hematoxylin and eosin, Bodian, Kluver-Barrera, and TUNEL. Neuronal cellular damage was evaluated by two pathologists blinded to the experimental conditions.

RESULTS

Group A displayed numerous cells with eosinophilic condensation of nuclear chromatin and proliferation of microglia in the hippocampus and basal ganglia. TUNEL-positive cells were observed in the periventricular area. Group B showed microglial proliferations, but no marked changes. No pathological changes were apparent in group C.

CONCLUSIONS

MCI-186 administered to the maternal circulation could inhibit fetal brain injury resulting from hypoxia-reperfusion induced by umbilical cord occlusion.