Edaravone's free radical scavenging mechanisms of neuroprotection against cerebral ischemia: review of the literature

Safety and efficacy of GD-11 in patients with ischaemic stroke: a multicentre, double-blind, randomised, placebo-controlled, phase 2 trial

BACKGROUND

GD-11, a novel brain cytoprotective drug, was designed to be actively taken up and transported across the blood-brain barrier via the glucose transporter. This study aimed to evaluate the safety and efficacy of GD-11 for improving the recovery of patients with acute ischaemic stroke (AIS).

METHODS

A double-blind, randomised, placebo-controlled, phase 2 trial was conducted at 15 clinical sites in China. Patients aged 18-80 years with AIS within 48 hours were randomly assigned (1:1:1) to receive 160 mg GD-11, 80 mg GD-11 and placebo, two times a day for 10 days. The primary endpoint was a modified Rankin Scale (mRS) score of 0-1 at 90 days after treatment. The safety outcome was any adverse events within 90 days.

RESULTS

From 17 November 2022 to 22 March 2023, a total of 80 patients in the 160 mg GD-11 group, 79 patients in the 80 mg GD-11 group and 80 patients in the placebo group were included. The proportion of an mRS score of 0-1 at day 90 was 77.5% in the 160 mg GD-11 group, 72.2% in the 80 mg GD-11 group and 67.5% in the placebo group. Though no significant difference was found (p=0.3671), a numerically higher proportion was observed in the GD-11 group, especially in the 160 mg GD-11 group. The incidence of adverse events was similar across the three groups (p=0.1992).

CONCLUSION

GD-11 was safe and well-tolerated. A dosage of GD-11 160 mg two times a day was recommended for a large trial to investigate the efficacy.

Design and Synthesis of Edaravone Derivatives Containing 6-(4-aminophenyl)-4,5-dihydropyridazin-3(2H)-one as Bifunctional Anti-ischemic Stroke Agents

Ischemic stroke gravely endangers human health. To develop novel drugs with antiplatelet and neuroprotective functions for ischemic stroke, edaravone derivatives CT01-CT20, containing 6-(4-aminophenyl)-4,5-dihydropyridazin-3(2H)-one, were synthesized from materials like dimethyl butynedioate, ethyl acetoacetate, and diethyl 1,3-acetonedicarboxylate, via cyclization, hydrolysis, and condensation. Among them, CT16 exhibited outstanding antiplatelet activity (IC50 = 6.72 µM), absent in edaravone. It also surpassed edaravone in 1,1-diphenyl-2-picrylhydrazyl radical scavenging (EC50 = 30.80 µM) and protecting PC12 cells from H₂O₂ damage. In vivo, CT16 effectively reduced carotid artery thrombosis in rats and enhanced blood flow. In the middle cerebral artery occlusion reperfusion injury model, it shrank infarct size, improved neurological scores, increased cerebral blood flow, and lessened brain edema. Preliminary safety tests indicated CT16 didn't alter rat blood biochemistry or organ pathology, with a low bleeding risk as an antiplatelet agent. Molecular docking suggested it may inhibit phosphodiesterase 3A to achieve an antiplatelet effect. In conclusion, CT16 has both antiplatelet aggregation and neuroprotective effects and is a potential candidate compound for the treatment of ischemic stroke.

Injectable Hierarchical Bioactive Hydrogels with Fibroblast Growth Factor 21/Edaravone/Caffeic Acid Asynchronous Delivery for Treating Parkinson's Disease

Parkinson's disease (PD) is one of the most common long-term neurodegenerative disorders, with multiple comorbid psychiatric and behavioral abnormalities. The combination of clinical drugs targeting different symptoms with smart hydrogels to achieve asynchronous releases is highly translational and challenging. Here, a hierarchical bioactive hydrogel (OACDP) is designed with asynchronous release based on PD pathology. The hydrogel with caffeic acid-grafted polymer main chain is crosslinked using a micellar nanocrosslinker, with sufficient modulus (≈167 Pa), antioxidant activity (> 50%), injectability (30-gauge syringe needle), and shape-adaptability. Each of the three drugs (caffeic acid, fibroblast growth factor 21, and Edaravone) is separately engaged in different micro- or nanostructures of the hydrogel and released with asynchronous kinetics of first-order release, zero-order release, or matching Korsmeyer-Peppas model. The triple-loaded hydrogel is injected into the brains of PD rats, showing behavioral improvement. Histological analysis revealed that the triple-loaded OACDP hydrogels are effective in achieving immediate neuroprotection, i.e., reduction the loss of tyrosine hydroxylase in substantia nigra compacta and striatum (retained ≈10-fold versus control), decreasing oxidative stress, reducing astrocyte and microglia activation, and stimulating the AMPK/PGC-1α axis to regulate the mitochondrial function, providing a multi-dimensional PD therapy. The asynchronous release of OACDP hydrogel provides a new conception for PD treatment and other neurodegenerative diseases.

Synergistic effects of neuroprotective drugs with intravenous recombinant tissue plasminogen activator in acute ischemic stroke: A Bayesian network meta-analysis

Neuroprotective drugs as adjunctive therapy for adults with acute ischemic stroke (AIS) remains contentious. This study summarizes the latest evidence regarding the benefits of neuroprotective agents combined with intravenous recombinant tissue plasminogen activator (rt-PA) intravenous thrombolysis. This study conducted a structured search of PubMed, the Cochrane Library, EMBASE, Wanfang Data, and CNKI databases from their inception to March 2024. Grey literature was also searched. The outcomes included efficacy (National Institutes of Health Stroke Scale (NIHSS) score and Barthel Index (BI) score) and safety (rate of adverse reactions). A total of 70 randomized controlled trials were selected for this network meta-analysis (NMA), encompassing 4,140 patients with AIS treated using different neuroprotective agents plus RT-PA, while 4,012 patients with AIS were in control groups. The top three treatments for NIHSS scores at the 2-week follow-up were Edaravone Dexborneo with 0.9 mg/kg rt-PA, Edaravone with 0.9 mg/kg rt-PA, and HUK with 0.9 mg/kg rt-PA. HUK with 0.9 mg/kg rt-PA, Dl-3n-butylphthalide with 0.9 mg/kg rt-PA, and Edaravone Dexborneo with 0.9 mg/kg rt-PA were ranked the top three for BI scores at the 2-week follow-up. The top three treatments with the lowest adverse effect rates were 0.6 mg/kg rt-PA, HUK with 0.9 mg/kg rt-PA, and Edaravone Dexborneo with 0.9 mg/kg rt-PA due to their excellent safety profiles. Compared to rt-PA alone, the combination treatments of Edaravone+rt-PA, Edaravone Dexborneol+rt-PA, HUK+rt-PA, Dl-3n-butylphthalide+rt-PA, and Ganglioside GM1+rt-PA have shown superior efficacy. This NMA suggest that combination therapies of neuroprotective agents and rt-PA can offer better outcomes for patients with AIS. The results support the potential integration of these combination therapies into standard AIS treatment, aiming for improved patient outcomes and personalized therapeutic approaches.

Identification of 3-methyl-1-(3-methylpyridin-2-yl)-1H-pyrazol-5-ol as promising neuroprotective agent

Pyrazolol derivatives are gaining significant attention for their diverse pharmacological effects, such as analgesic, anti-inflammatory, antioxidant, and anticancer activities. In this study, 20 pyrazolol derivatives were designed and synthesized to develop an anti-ischemic stroke formulation with free radical scavenging activity. Most of these synthesized compounds demonstrated antioxidant capabilities in DPPH, ABTS radical scavenging, and ORACFL assays. The methyl-substituted compound Y12, in particular, showed exceptional antioxidant capacity. Additionally, these compounds showed excellent neurocytoprotective effects in the SH-SY5Y cell injury model subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). Notably, Y12 exhibited significant metal chelating activity with Cu2+. In vivo studies confirmed that compound Y12 has neuroprotective effects and can significantly reduce the infarct area in a mouse model of focal cerebral ischemia induced by transient middle cerebral artery occlusion (tMCAO).

Exploring the anti-ischemic stroke potential of wogonoside: Insights from Nrf2/Sirt3 signaling pathway and UPLC-TripleTOF-MS/MS-based metabolomics

Ischemic stroke, accounting for 80 % of all strokes, is a major cause of morbidity and mortality worldwide. However, effective and safe pharmacotherapy options for ischemic injury are limited. This study investigated the therapeutic effects of wogonoside, a compound derived from Radix Scutellariae, on ischemia/reperfusion (I/R) injury. The results showed that wogonoside treatment had significant therapeutic effects in rats with middle cerebral artery occlusion. It effectively reduced mortality rates, neurological deficits, cerebral infarct size, and brain water content. In an in vitro model using PC12 cells, wogonoside activated the Nrf2/Sirt3 signaling pathway. This activation contributed to the attenuation of oxidative damage and inflammation. Metabolomics analysis revealed increased levels of γ-aminobutyric acid (GABA) and glutathione in response to wogonoside treatment, suggesting their potential as therapeutic biomarkers for ischemic stroke. Additionally, wogonoside restored perturbed energy metabolism, including the tricarboxylic acid cycle. Wogonoside has the potential to ameliorate cerebral ischemic injury by targeting GABA-related amino acid metabolism, energy metabolism, and glutathione metabolism, maintaining redox homeostasis, and attenuating oxidative stress. These findings provide valuable insights into the protective mechanisms of wogonoside in cerebral I/R injury and highlight the promising therapeutic approach of wogonoside in the treatment of ischemic stroke.

Therapeutic effect and psychological impact of aspirin plus edaravone on patients with cerebral infarction

BACKGROUND

Cerebral infarction (CI) is characterized by a high prevalence, disability, and mortality. Timely or improper treatment greatly affects patient prognosis.

AIM

To explore the drug efficacy of aspirin plus edaravone and to explore their effect on quality of life (QOL), anxiety and depression in CI patients.

METHODS

We retrospectively analyzed the records of 124 CI patients treated between June 2019 and February 2021 who were assigned to an observation group (OG) (combination therapy of aspirin and edaravone, 65 patients) or a control group (CG) (aspirin monotherapy, 59 patients). The therapeutic effects, pre- and posttreatment National Institutes of Health Stroke Scale (NIHSS) scores, activities of daily living, degree of cognitive impairment, protein levels of glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE) and S-100B, occurrence of adverse reactions, and serum high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6 and tumor necrosis factor (TNF)-α were evaluated, detected and compared between the two groups. Finally, posttreatment QOL, anxiety, and depression were assessed by the Medical Outcomes Study 36- Item Short Form Health Survey Scale, Self-rating Depression Scale (SDS), and Self-rating Anxiety Scale (SAS), respectively.

RESULTS

Compared with the CG, the OG had markedly better therapeutic effects, greater improvements in activities of daily living, and better alleviation in cognitive dysfunction after treatment, as well as lower posttreatment NIHSS scores and serum NSE, GFAP, S-100B, hs-CRP, IL-6, and TNF-α levels; the OG was similar to the CG in terms of adverse reactions but was better than the CG in terms of posttreatment QOL; and the OG also had lower SDS and SAS scores than the CG after treatment.

CONCLUSION

Aspirin plus edaravone had a good curative effect on CI. It can reverse cranial nerve damage in patients, improve neurological function and prognosis, and alleviate inflammation, anxiety, and depression; thus, it is considered safe and worthy of clinical application.

Discovery of Novel Hybrids of Edaravone and 6-Phenyl-4,5-dihydropyridazin-3(2H)-one with Antiplatelet Aggregation and Neuroprotection for Ischemic Stroke Treatment

Drugs with anti-platelet aggregation and neuroprotection are of great significance for the treatment of ischemic stroke. A series of edaravone and 6-phenyl-4,5-dihydropyridazin-3(2H)-one hybrids were designed and synthesized. Among them, 6g showed the most effective cytoprotective effect against oxygen-glucose deprivation/reoxygenation-induced damage in BV2 cells and an excellent inhibitory effect on platelet aggregation induced by adenosine diphosphate and arachidonic acid. Additionally, 6g could prevent thrombosis caused by ferric chloride in rats and pose a lower risk of causing bleeding compared with aspirin. It provides better protection against ischemia/reperfusion injury in rats compared with edaravone and alleviates the oxidative stress related to cerebral ischemia/reperfusion by increasing the GSH and SOD levels and decreasing the MDA concentration. Finally, molecular docking results showed that 6g probably acts on PDE3 A and plays an anti-platelet aggregation effect. Overall, 6g could be a potential candidate compound for the treatment of ischemic stroke.

Effect of Cyclosporin H on ischemic injury and neutrophil infiltration in cerebral infarct model of rats via PET imaging

BACKGROUND

Brain ischemia-reperfusion injury is a complex process, and neuroinflammation is an important secondary contributing pathological event. Neutrophils play major roles in ischemic neuroinflammation. Once activated, neutrophils express formyl peptide receptors (FPRs), which are special receptors of a class of chemoattractants and may be potential targets to regulate the activity of neutrophils and control cerebral ischemic injury. This study was aimed to explore the ameliorating effect of Cyclosporin H (CsH), a potent FPR antagonist, on brain ischemic injury by inhibiting the activation and migration of neutrophils, and improving cerebral blood flow.

METHODS

We employed a middle cerebral artery occlusion (MCAO) Model on rats and performed behavioral, morphological, and microPET imaging assays to investigate the potential restoring efficacy of CsH on cerebral ischemic damages. Peptide N-cinnamoyl-F-(D)L-F-(D)L-F (cFLFLF), an antagonist to the neutrophil FPR with a high binding affinity, was used for imaging neutrophil distribution.

RESULTS

We found that CsH had similar effect with edaravone on improving the neurobehavioral deficient symptoms after cerebral ischemia-reperfusion, and treatment with CsH also alleviated ischemic cerebral infarction. Compared with the MCAO Model group, [18F]FDG uptake ratios of the CsH and edaravone treatment groups were significantly higher. The CsH-treated groups also showed significant increases in [18F]FDG uptake at 144 h when compared with that of 24 h. This result indicates that like edaravone, treatment with both doses of CsH promoted the recovery of blood supply after cerebral ischemic event. Moreover, MCAO-induced cerebral ischemia significantly increased the radiouptake of [68Ga]Ga-cFLFLF at 72 h after ischemia-reperfusion operation. Compared with MCAO Model group, radiouptake values of [68Ga]-cFLFLF in both doses of CsH and edaravone groups were all decreased significantly. These results showed that both doses of CsH resulted in a similar therapeutic effect with edaravone on inhibiting neutrophil infiltration in cerebral infarction.

CONCLUSION

Potent FPR antagonist CsH is promisingly beneficial in attenuating neuroinflammation and improving neurobehavioral function against cerebral infarction. Therefore, FPR may become a novel target for regulating neuroinflammation and improving prognosis for ischemic cerebrovascular disorders.

Compound Shenma Jingfu granule alleviates cerebral ischemia via HIF-1α-mediated promotion of angiogenesis

BACKGROUND

Shenma Jingfu Granule, a traditional Chinese medicine formula, has been used clinically for the treatment of cerebral circulation insufficiency. However, the mechanism involved in alleviating cerebral ischemia has not yet been fully elucidated.

METHODS

An integrated approach involving network pharmacology and transcriptomics was utilized to clarify the potential mechanisms of SMJF Granule. Molecular docking and surface plasmon resonance (SPR) were employed to identify potential targets and ingredients of SMJF Granule. The anti-CI effect of SMJF Granule was determined on the middle cerebral artery occlusion (MCAO) model by using hematoxylin-eosin (H&E) and Nissl's staining, as well as triphenyl tetrazolium chloride (TTC) staining, and the potential targets involved in the mechanisms were validated by RT-qPCR and western blotting.

RESULTS

Integrated analysis revealed the mechanism of SMJF Granule intervening in CI injury might be related to the HIF-1 signaling pathway and angiogenesis. Molecular docking and SPR assays demonstrated robust binding interactions between key compounds like salvianolic acid A and naringenin with the core target HIF-1α protein. The experiment confirmed that SMJF Granule lowered neurological scores, diminished infarct volume, and alleviated histopathological changes in vivo. The possible mechanism of SMJF Granule was due to regulating HIF-1 pathway, which contributed to up-regulating expression of VEGF and vWF in the penumbral region, showing a significant promotion of angiogenesis.

CONCLUSION

SMJF Granule promoted angiogenesis through HIF-1α pathway, thereby alleviating cerebral ischemia injury. In addition, our findings provide some evidence that SMJF Granule is a candidate compound for further investigation in treating CI in the clinical.

Experimental Treatment with Edaravone in a Mouse Model of Spinocerebellar Ataxia 1

Edaravone is a mitochondrially targeted drug with a suggested capability to modify the course of diverse neurological diseases. Nevertheless, edaravone has not been tested yet in the context of spinocerebellar ataxia 1 (SCA1), an incurable neurodegenerative disease characterized mainly by cerebellar disorder, with a strong contribution of inflammation and mitochondrial dysfunction. This study aimed to address this gap, exploring the potential of edaravone to slow down SCA1 progression in a mouse knock-in SCA1 model. SCA1^154Q/2Q and healthy SCA1^2Q/2Q mice were administered either edaravone or saline daily for more than 13 weeks. The functional impairments were assessed via a wide spectrum of behavioral assays reflecting motor and cognitive deficits and behavioral abnormalities. Moreover, we used high-resolution respirometry to explore mitochondrial function, and immunohistochemical and biochemical tools to assess the magnitude of neurodegeneration, inflammation, and neuroplasticity. Data were analyzed using (hierarchical) Bayesian regression models, combined with the methods of multivariate statistics. Our analysis pointed out various previously documented neurological and behavioral deficits of SCA1 mice. However, we did not detect any plausible therapeutic effect of edaravone on either behavioral dysfunctions or other disease hallmarks in SCA1 mice. Thus, our results did not provide support for the therapeutic potential of edaravone in SCA1.

Myricetin improves apoptosis after ischemic stroke via inhibiting MAPK-ERK pathway

BACKGROUND

Neuronal apoptosis is the main cause for the disabilities and deaths of patients suffered with stroke. Neuroprotectants are clinically used to reduce neuronal apoptosis in ischemic stroke. However, the current neuroprotectants have multiple limitations. Myricetin is beneficial for multiple neurodegenerative diseases, but the role of myricetin as a neuroprotective agent in ischemic stroke is still not fully understood.

METHODS AND RESULTS

Middle cerebral artery occlusion, Terminal deoxynucleotidyl transferase dUTP nick-end labeling staining and Western blots were used to explore the anti-apoptotic effects of myricetin in vivo. Flow cytometry, Western blots and Ca²⁺ staining were used to study the neuroprotective effects of myricetin in vitro. In this study, we first demonstrated that myricetin reduced neuronal apoptosis after ischemia in vivo and in vitro. And, among the factors of apoptosis after ischemic stroke, excitotoxicity, oxidative stress and inflammation-induced apoptosis can be alleviated by myricetin. Moreover, we further demonstrated that myricetin was able to improve neuronal intrinsic apoptosis by inhibiting the phosphorylation of extracellular signal-regulated kinase in the oxygen and glucose deprivation in vitro.

CONCLUSIONS

Summarily, our results support myricetin as a novel neuroprotectant for the prevention or treatment of ischemic stroke via MAPK-ERK signaling pathway.

Mangiferin: the miraculous xanthone with diverse pharmacological properties

Mangiferin (1,3,6,7-tetrahydroxy-2-[3,4,5-trihydroxy-6-(hydroxymethyl) oxan-2-yl] xanthen-9-one) is a bioactive component derived primarily from the mango tree. Belonging to the Xanthone family, its structure allows it to engage with a variety of pharmacological targets. The symmetric linked core of xanthones has a heterogeneous biogenetic background. The carbon atoms are designated in a biochemical order, which reveals the reason of ring A (C1-C4) being referred to as acetate originated, and ring B (C5-C8) is referred to as shikimate originated. The antibacterial, hypocholesterolemic, antiallergic, cardiotonic, antidiabetic, anti-neoplastic, neuroprotective, antioxidant and immunomodulatory properties have all been demonstrated for the secondary metabolite. This study assessed and explained the important medical properties of mangiferin available in published literature, as well as its natural source, biosynthesis, absorption and bioavailability; multiple administration routes; metabolism; nanotechnology for enhanced efficacy of mangiferin and its toxicity, to aid the anticipated on-going potential of mangiferin as a novel diagnostic treatment.

Neuroprotective Efficacy of Edaravone against Arsenic-Induced Behavioral and Neurochemical Deficits in Rats: Amelioration of Cholinergic and Mitochondrial Functions

BACKGROUND

A substantial amount of evidence indicates that long-term arsenic exposure leads to various types of pathological complications, especially cognitive dysfunction.

OBJECTIVE

The present study was designed to assess the neuroprotective potential of edaravone (a potent free radical scavenger) against arsenic-induced neurotoxicity in Wistar rats.

METHODS

Adult male Wistar rats were randomly divided into five groups. Arsenic (20 mg/kg/day; p.o.) and Edaravone (5 and 10 mg/kg/day; i.p.) were administered in different experimental groups for 28 days.

RESULTS

The results of various behavioral test paradigms revealed that arsenic caused significant learning and memory deficits, along with anxiety-like behavior. In biochemical analysis, we found marked elevations of oxidative-nitrosative stress (indicated by augmentation of lipid peroxidation and nitrite) and a reduction of glutathione levels in the hippocampus and frontal cortex region of arsenictreated rats. Moreover, arsenic administration caused mitochondrial complexes impairment and reduction of acetylcholinesterase level. On the other hand, chronic treatment with edaravone (10 mg/kg) significantly ameliorated the arsenic-induced behavioral deficits and neurochemical anomalies.

CONCLUSION

This study suggests that edaravone confers neuroprotection against arsenic-induced memory impairment and anxiety-like behavior, which may be attributed to the inhibition of oxidativenitrosative stress and amelioration of cholinergic and mitochondrial functions.

Synthesis of 4-Aminopyrazol-5-ols as Edaravone Analogs and Their Antioxidant Activity

One of the powerful antioxidants used clinically is Edaravone (EDA). We synthesized a series of new EDA analogs, 4-aminopyrazol-5-ol hydrochlorides, including polyfluoroalkyl derivatives, via the reduction of 4-hydroxyiminopyrazol-5-ones. The primary antioxidant activity of the compounds in comparison with EDA was investigated in vitro using ABTS, FRAP, and ORAC tests. In all tests, 4-Amino-3-pyrazol-5-ols were effective. The lead compound, 4-amino-3-methyl-1-phenylpyrazol-5-ol hydrochloride (APH), showed the following activities: ABTS, 0.93 TEAC; FRAP, 0.98 TE; and ORAC, 4.39 TE. APH and its NH-analog were not cytotoxic against cultured normal human fibroblasts even at 100 μM, in contrast to EDA. According to QM calculations, 4-aminopyrazolols were characterized by lower gaps, IP, and η compared to 4-hydroxyiminopyrazol-5-ones, consistent with their higher antioxidant activities in ABTS and FRAP tests, realized by the SET mechanism. The radical-scavenging action evaluated in the ORAC test occurred by the HAT mechanism through OH bond breaking in all compounds, directly dependent on the dissociation energy of the OH bond. All the studied compounds demonstrated the absence of anticholinesterase activity and moderate inhibition of CES by some 4-aminopyrazolols. Thus, the lead compound APH was found to be a good antioxidant with the potential to be developed as a novel therapeutic drug candidate in the treatment of diseases associated with oxidative stress.

Antioxidant Properties and Aldehyde Reactivity of PD-L1 Targeted Aryl-Pyrazolone Anticancer Agents

Small molecules targeting the PD-1/PD-L1 checkpoint are actively searched to complement the anticancer arsenal. Different molecular scaffolds have been reported, including phenyl-pyrazolone derivatives which potently inhibit binding of PD-L1 to PD-1. These molecules are structurally close to antioxidant drug edaravone (EDA) used to treat amyotrophic lateral sclerosis. For this reason, we investigated the capacity of five PD-L1-binding phenyl-pyrazolone compounds (1–5) to scavenge the formation of oxygen free radicals using electron spin resonance spectroscopy with DPPH/DMPO probes. In addition, the reactivity of the compounds toward the oxidized base 5-formyluracil (5fU) was assessed using chromatography coupled to mass spectrometry and photodiode array detectors. The data revealed that the phenyl-pyrazolone derivatives display antioxidant properties and exhibit a variable reactivity toward 5fU. Compound 2 with a N-dichlorophenyl-pyrazolone moiety cumulates the three properties, being a potent PD-L1 binder, a robust antioxidant and an aldehyde-reactive compound. On the opposite, the adamantane derivative 5 is a potent PD-L1 binding with a reduced antioxidant potential and no aldehyde reactivity. The nature of the substituent on the phenyl-pyrazolone core modulates the antioxidant capacity and reactivity toward aromatic aldehydes. The molecular signature of the compound can be adapted at will, to confer additional properties to these PD-L1 binders.

Safety and Effectiveness of Long-term Intravenous Administration of Edaravone for Treatment of Patients With Amyotrophic Lateral Sclerosis

Importance

Intravenous edaravone is approved as a disease-modifying drug for patients with amyotrophic lateral sclerosis (ALS), but evidence for efficacy is limited to short-term beneficial effects shown in the MCI186-ALS19 study in a subpopulation in which efficacy was expected.

Objective

To evaluate the long-term safety and effectiveness of intravenous edaravone therapy for patients with ALS in a real-world clinical setting.

Design, Setting, and Participants

Multicenter, propensity score-matched cohort study conducted between June 2017 and March 2020 at 12 academic ALS referral centers associated with the German Motor Neuron Disease Network. Of 1440 patients screened, 738 were included in propensity score matching. Final analyses included 324 patients with ALS comprising 194 patients who started intravenous edaravone treatment (141 received ≥4 consecutive treatment cycles; 130 matched) and 130 propensity score-matched patients with ALS receiving standard therapy. All patients had probable or definite ALS according to the El Escorial criteria, with disease onset between December 2012 and April 2019. Subgroups were defined by applying the MCI186-ALS19 study inclusion criteria to evaluate whether patients would have been considered eligible (EFAS) or ineligible (non-EFAS).

Exposures

Intravenous edaravone plus riluzole vs riluzole only.

Main Outcomes and Measures

Patient characteristics and systematic safety assessment for patients who received at least 1 dose of intravenous edaravone. Effectiveness assessment of edaravone was conducted among patients who received at least 4 treatment cycles compared with propensity score-matched patients with ALS who received only standard therapy. Primary outcome was disease progression measured by decrease in the ALS Functional Rating Scale-Revised (ALSFRS-R) score. Secondary outcomes were survival probability, time to ventilation, and change in disease progression before vs during treatment. To account for the matched design, patients receiving edaravone and their corresponding matched controls were regarded as related samples in disease progression analyses; stratification for propensity score quintiles was used for survival probability and time to ventilation analyses.

Results

A total of 194 patients started intravenous edaravone treatment; 125 (64%) were male, and the median age was 57.5 years (IQR, 50.7-63.8 years). Potential adverse effects were observed in 30 cases (16%), most notably infections at infusion sites and allergic reactions. Disease progression among 116 patients treated for a median of 13.9 months (IQR, 8.9-13.9 months) with edaravone did not differ from 116 patients treated for a median of 11.2 months (IQR, 6.4-20.0 months) with standard therapy (ALSFRS-R points/month, -0.91 [95% CI, -0.69 to -1.07] vs -0.85 [95% CI, -0.66 to -0.99]; P = .37). No significant differences were observed in the secondary end points of survival probability, time to ventilation, and change in disease progression. Similarly, outcomes between patients treated with edaravone and matched patients did not differ within the EFAS and non-EFAS subgroups.

Conclusions and Relevance

This cohort study using propensity score matching found that, although long-term intravenous edaravone therapy for patients with ALS was feasible and mainly well tolerated, it was not associated with any disease-modifying benefit. Intravenous edaravone may not provide a clinically relevant additional benefit compared with standard therapy alone.

Adjunctive cytoprotective therapies in acute ischemic stroke: a systematic review

With the introduction of endovascular thrombectomy (EVT), a new era for treatment of acute ischemic stroke (AIS) has arrived. However, despite the much larger recanalization rate as compared to thrombolysis alone, final outcome remains far from ideal. This raises the question if some of the previously tested neuroprotective drugs warrant re-evaluation, since these compounds were all tested in studies where large-vessel recanalization was rarely achieved in the acute phase. This review provides an overview of compounds tested in clinical AIS trials and gives insight into which of these drugs warrant a re-evaluation as an add-on therapy for AIS in the era of EVT. A literature search was performed using the search terms "ischemic stroke brain" in title/abstract, and additional filters. After exclusion of papers using pre-defined selection criteria, a total of 89 trials were eligible for review which reported on 56 unique compounds. Trial compounds were divided into 6 categories based on their perceived mode of action: systemic haemodynamics, excitotoxicity, neuro-inflammation, blood-brain barrier and vasogenic edema, oxidative and nitrosative stress, neurogenesis/-regeneration and -recovery. Main trial outcomes and safety issues are summarized and promising compounds for re-evaluation are highlighted. Looking at group effect, drugs intervening with oxidative and nitrosative stress and neurogenesis/-regeneration and -recovery appear to have a favourable safety profile and show the most promising results regarding efficacy. Finally, possible theories behind individual and group effects are discussed and recommendation for promising treatment strategies are described.

Edaravone combined with dexamethasone exhibits synergic effects on attenuating smoke-induced inhalation lung injury in rats

Inhalational lung injury often leads to morbidity and mortality during fire disasters. In this study, we aimed to evaluate the protective effects of edaravone combined with dexamethasone on smoke-induced inhalational lung injury. Sprague-Dawley rats were divided into five groups, namely, the control, model (inhalation), and three treatment groups (edaravone, dexamethasone, and edaravone combined with dexamethasone). After drug intervention in the acute lung injury model, arterial blood gas, wet:dry weight ratio of the lung tissue, bronchoalveolar lavage fluid, and pulmonary histopathology were determined. The production of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), inflammatory cytokines, peroxidase and apoptosis were further analyzed to explore the underlying mechanisms. The results of blood gas and inflammatory cytokine analysis and the histopathological data demonstrated that edaravone combined with dexamethasone had obvious protective effects on smoke infiltration and tissue injury. Moreover, after the co-administration of edaravone and dexamethasone, malondialdehyde and myeloperoxidase levels in the lung tissue decreased, whereas those of glutathione peroxidase and superoxide dismutase were elevated. In addition, this drug combination could inhibit smoke-induced apoptosis in lung tissues by reducing the cleavage of caspase-3, caspase-9, and poly ADP-ribose polymerase (PARP), and also reverse smoke-mediated mitochondrial dysfunction, including ROS generation, loss of MMP, early release of cytochrome C, second mitochondrial activator of caspases, and apoptosis-inducing factor. In conclusion, edaravone combined with dexamethasone had a protective effect on smoke-induced inhalational lung injury in rats and can be further explored as an attractive therapeutic option for the treatment of smoke inhalation-induced pulmonary dysfunction.

Mangiferin as New Potential Anti-Cancer Agent and Mangiferin-Integrated Polymer Systems-A Novel Research Direction

For a long time, the pharmaceutical industry focused on natural biologically active molecules due to their unique properties, availability and significantly less side-effects. Mangiferin is a naturally occurring C-glucosylxantone that has substantial potential for the treatment of various diseases thanks to its numerous biological activities. Many research studies have proven that mangiferin possesses antioxidant, anti-infection, anti-cancer, anti-diabetic, cardiovascular, neuroprotective properties and it also increases immunity. It is especially important that it has no toxicity. However, mangiferin is not being currently applied to clinical use because its oral bioavailability as well as its absorption in the body are too low. To improve the solubility, enhance the biological action and bioavailability, mangiferin integrated polymer systems have been developed. In this paper, we review molecular mechanisms of anti-cancer action as well as a number of designed polymer-mangiferin systems. Taking together, mangiferin is a very promising anti-cancer molecule with excellent properties and the absence of toxicity.

Mechanical Reperfusion Following Prolonged Global Cerebral Ischemia Attenuates Brain Injury

Previous experiments demonstrated improved outcome following prolonged cerebral ischemia given controlled brain reperfusion using extracorporeal circulation. The current study further investigates this. Young adult pigs were exposed to 30 min of global normothermic cerebral ischemia, achieved through intrathoracic clamping of cerebral arteries, followed by 20 min of isolated mechanical brain reperfusion. Leukocyte-filtered blood was delivered by a roller-pump at fixed pressure and flow. One experimental group additionally had a custom-made buffer solution delivered at 1:8 ratio with the blood. Hemodynamics including intracranial pressure were monitored. Blood gases were from peripheral arteries and the sagittal sinus, and intraparenchymal brain microdialysis was performed. The brains were examined by a neuropathologist. The group with the added buffer showed lower intracranial pressure as well as decreased intraparenchymal glycerol and less signs of excitotoxicity and ischemia, although histology revealed similar degrees of injury. A customized mechanical reperfusion improves multiple parameters after prolonged normothermic global cerebral ischemia.

Graphical Abstract

Biomaterials to Neuroprotect the Stroke Brain: A Large Opportunity for Narrow Time Windows

Ischemic stroke represents one of the most prevalent pathologies in humans and is a leading cause of death and disability. Anti-thrombolytic therapy with tissue plasminogen activator (t-PA) and surgical thrombectomy are the primary treatments to recanalize occluded vessels and normalize the blood flow in ischemic and peri-ischemic regions. A large majority of stroke patients are refractory to treatment or are not eligible due to the narrow time window of therapeutic efficacy. In recent decades, we have significantly increased our knowledge of the molecular and cellular mechanisms that inexorably lead to progressive damage in infarcted and peri-lesional brain areas. As a result, promising neuroprotective targets have been identified and exploited in several stroke models. However, these considerable advances have been unsuccessful in clinical contexts. This lack of clinical translatability and the emerging use of biomaterials in different biomedical disciplines have contributed to developing a new class of biomaterial-based systems for the better control of drug delivery in cerebral disorders. These systems are based on specific polymer formulations structured in nanoparticles and hydrogels that can be administered through different routes and, in general, bring the concentrations of drugs to therapeutic levels for prolonged times. In this review, we first provide the general context of the molecular and cellular mechanisms impaired by cerebral ischemia, highlighting the role of excitotoxicity, inflammation, oxidative stress, and depolarization waves as the main pathways and targets to promote neuroprotection avoiding neuronal dysfunction. In the second part, we discuss the versatile role played by distinct biomaterials and formats to support the sustained administration of particular compounds to neuroprotect the cerebral tissue at risk of damage.

Neuroprotective effects of oleic acid in rodent models of cerebral ischaemia

Oleic acid (OA) is released from brain phospholipids after cerebral ischaemia; however, its role in ischaemic injury remains unknown. We hypothesised that OA has neuroprotective effects after cerebral ischaemia, which may be exerted through peroxisome proliferator-activated receptor gamma (PPAR-γ) activation, since OA is an endogenous ligand of PPAR-γ. The effects of OA administration were evaluated in rodent models of middle cerebral artery occlusion (MCAO), photothrombosis, and four-vessel occlusion (4-VO). We determined the time window of therapeutic opportunity and examined the ability of the PPAR-γ antagonist GW9662 to reverse OA’s protective effects after MCAO. We found that OA administration decreased the MCAO-induced infarct volume and functional deficits, photothrombosis-induced infarct volume, and 4-VO-induced hippocampal neuronal death. Additionally, OA was highly efficacious when administered up to 3 h after MCAO. Pre-treatment with GW9662 abolished the inhibitory effects of OA on the infarct volume and immunoreactivity of key inflammatory mediators in the ischaemic cortex. Our results indicate that OA has neuroprotective effects against transient and permanent focal cerebral ischaemia, as well as global cerebral ischaemia. It may have therapeutic value for the ischaemic stroke treatment with a clinically feasible therapeutic window. The OA-mediated neuroprotection might be attributable to its anti-inflammatory actions through PPAR-γ activation.

Orally Administered Crocin Protects Against Cerebral Ischemia/Reperfusion Injury Through the Metabolic Transformation of Crocetin by Gut Microbiota

Our pilot study suggested that orally administered crocin was hardly absorbed into circulatory system, but it was effective against cerebral ischemic/reperfusion (I/R) injury. The pharmacologically active component and targeting site of crocin remain elusive. In this study, the cerebral-protective effect of crocin was evaluated on a rat transient middle cerebral artery occlusion (MCAO) model. Our data showed that oral administration of crocin had better effectiveness in cerebral protection than an intravenous injection. Neither crocin nor its metabolite crocetin were determined in the brain of cerebral I/R rats, indicating a target site of periphery. Abundant crocetin was detected in plasma after oral administration instead of intravenous injection of crocin. Meanwhile, orally administered crocetin showed similar cerebral protection to that of crocin, but this exciting effect was not clearly observed by intravenous administration of crocetin, indicating the importance of crocetin in gut. Moreover, orally administered crocin showed less cerebral-protective effect in pseudo germ-free (pGF) MCAO rats. In vitro and in vivo experiments confirmed that crocin could be deglycosylated to crocetin in gut content of normal rats, rather than that of pGF rats, indicating that gut microbiota facilitated the transformation of crocin into crocetin, which played a key role in the activation of the pharmacological effect. Metabolomic study revealed that microbial-host co-metabolic molecules were significantly perturbed after oral administration of crocin, indicating a regulation on intestinal ecosystem. It was further suggested that gut microbiota may be the potential target of the cerebral-protective effect of crocin.

Mangiferin: An effective therapeutic agent against several disorders (Review)

Mangiferin (1,3,6,7‑tetrahydroxyxanthone‑C2‑β‑D‑glucoside) is a bioactive ingredient predominantly isolated from the mango tree, with potent antioxidant activity and multifactorial pharmacological effects, including antidiabetic, antitumor, lipometabolism regulating, cardioprotective, anti‑hyperuricemic, neuroprotective, antioxidant, anti‑inflammatory, antipyretic, analgesic, antibacterial, antiviral and immunomodulatory effects. Therefore, it possesses several health‑endorsing properties and is a promising candidate for further research and development. However, low solubility, mucosal permeability and bioavailability restrict the development of mangiferin as a clinical therapeutic, and chemical and physical modification is required to expand its application. This review comprehensively analyzed and collectively summarized the primary pharmacological actions of mangiferin that have been demonstrated in the literature, to support the potential future development of mangiferin as a novel therapeutic drug.

Pyrano[3,2-a]carbazole alkaloids as effective agents against ischemic stroke in vitro and in vivo

A series of pyrano[3,2-a]carbazole alkaloids were designed and synthesized as analogues of Claulansine F (Clau F, 10a) isolated from Clausena lansium. Some of compounds showed strong neuroprotective effects and were promising agents against ischemic stroke. Among these compounds, 7c was the most active in inhibiting the programmed death of PC12 cells and primary cortical neurons. This compound induced neuroprotection following ischemic reperfusion and decreased neurological deficit scores in treated animals. Furthermore, 7c could penetrate the blood-brain barrier (BBB) in rats, and its exposure in the brain was 4.3-fold higher than that in plasma. More importantly, compared to edaravone, 7c exhibited stronger free radical scavenging activity. Our findings suggest that 7c may be promising for further evaluation as an intervention for ischemic stroke.

Hydrogen Gas Inhalation Treatment in Acute Cerebral Infarction: A Randomized Controlled Clinical Study on Safety and Neuroprotection

BACKGROUND

Molecular hydrogen (H₂) acts as a therapeutic antioxidant. Inhalation of H₂ gas (1-4%) was effective for the improvement of cerebral infarction in multiple animal experiments. Thus, for actual applications, a randomized controlled clinical study is desired to evaluate the effects of inhalation of H₂ gas. Here, we evaluate the H₂ treatment on acute cerebral infarction.

METHODS

Through this randomized controlled clinical study, we assessed the safety and effectiveness of H₂ treatment in patients with cerebral infarction in an acute stage with mild- to moderate-severity National Institute of Health Stroke Scale (NIHSS) scores (NIHSS = 2-6). We enrolled 50 patients (25 each in the H₂ group and the control group) with a therapeutic time window of 6 to 24 hours. The H₂ group inhaled 3% H₂ gas (1 hour twice a day), and the control group received conventional intravenous medications for the initial 7 days. The evaluations included daily vital signs, NIHSS scores, physical therapy indices, weekly blood chemistry, and brain magnetic resonance imaging (MRI) scans over the 2-week study period.

RESULTS

The H₂ group showed no significant adverse effects with improvements in oxygen saturation. The following significant effects were found: the relative signal intensity of MRI, which indicated the severity of the infarction site, NIHSS scores for clinically quantifying stroke severity, and physical therapy evaluation, as judged by the Barthel Index.

CONCLUSIONS

H₂ treatment was safe and effective in patients with acute cerebral infarction. These results suggested a potential for widespread and general application of H₂ gas.

Picroside II protects the blood-brain barrier by inhibiting the oxidative signaling pathway in cerebral ischemia-reperfusion injury

BACKGROUND AND PURPOSE

Thrombolysis is used to improve cerebral circulation; at the same time, neuroprotective drugs such as antioxidants should also be used. The aim of these experiments was to explore the protective mechanism of an antioxidant, picroside II, on the blood-brain barrier (BBB) after cerebral ischemia-reperfusion (CI/R) injury.

METHODS

To observe the antagonistic effect of picroside II on CI/R damage, the neurological deficit score and the infarct volume were measured. To detect the protective effect of picroside II on nerve cells and the BBB, the morphology and structure of cortical brain tissue were observed, respectively. To investigate the antioxidant effect and mechanism of picroside II, reactive oxygen species (ROS) content, the activity of Nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase), and the protein levels of Nox2 and Rac-1 were detected. To investigate the protective mechanism of picroside II on the BBB, the levels of ROCK, MLCK, MMP-2 and claudin-5 were tested.

RESULTS

A higher neurological score, bigger cortex infarction, more damaged neuron structure and injured BBB, increased content of ROS and activity of NADPH oxidase, higher protein levels of Nox2, Rac-1, ROCK, MLCK and MMP-2 and lower levels of claudin-5 were observed in the model group. In the picroside group, the neurological score, neuronal damage, BBB injury, ROS content and NADPH oxidase activity were reduced (P<0.05), and the protein levels of Rac-1, Nox2, ROCK, MLCK and MMP-2 were down-regulated (P<0.05), while the expression of claudin-5 was up-regulated (P<0.05).

CONCLUSIONS

Picroside II could protect the nervous system possibly through reducing the content of ROS by down-regulating the expression of Rac-1 and Nox2 and could protect the BBB through reducing the expression of ROCK, MLCK, and MMP-2, while enhancing the expression of claudin-5.

Investigation of Linarinic acid and one of its derivatives against cerebral ischemia in mice

The study aims to investigate the effects of (-)-Linarinic acid (LA) and one of its derivatives (LA_d) on brain injury induced by ischemia. Malonaldehyde (MDA) is determined as an index for lipid peroxidation both in vitro and vivo. Mice were pre-treated with LA and LA_d for 3 d. Thereafter, they were induced to have incomplete cerebral ischemia with both bilateral carotid artery occlusion and hypotension (BCAOH). In the first part of the in vivo experiment, mice were divided into four groups: sham (control), ischemia, ischemia + LA (200 mg/kg, i.g.) and ischemia + LA_d (200 mg/kg, i.g.). In the second part, the dose-response of LA_d was investigated at 100, 200 and 400 mg/kg i.g., respectively. A modified neurological severity score was developed for evaluating behavioral deficits of the mice with ischemia. Brains of the mice were excised in order to determinate MDA after ischemia for 6 h. Survival time, survival rate, neurological injury score and MDA level in brains were observed. Results were: 1) The data in vitro showed that both LA and LA_d could inhibit the generation of MDA. IC₅₀ values obtained by Probit analysis were 2.9 mM for LA_d and 4.88 mM for LA; 2) BCAOH could significantly shorten the survival span, reduce the survival rate and cause neurological deficits, which were associated with high level of lipid hydroperoxide production in cerebral tissues; 3) LA_d decreased lipid peroxidation and improved the neurological outcome more than LA. It is concluded that LA_d offers a better neuroprotection than LA against brain damage caused by cerebral ischemia.

One-Compound-Multi-Target: Combination Prospect of Natural Compounds with Thrombolytic Therapy in Acute Ischemic Stroke

Tissue plasminogen activator (t-PA) is the only FDA-approved drug for acute ischemic stroke treatment, but its clinical use is limited due to the narrow therapeutic time window and severe adverse effects, including hemorrhagic transformation (HT) and neurotoxicity. One of the potential resolutions is to use adjunct therapies to reduce the side effects and extend t-PA&#039;s therapeutic time window. However, therapies modulating single target seem not to be satisfied, and a multitarget strategy is warranted to resolve such complex disease. Recently, large amount of efforts have been made to explore the active compounds from herbal supplements to treat ischemic stroke. Some natural compounds revealed both neuro- and bloodbrain- barrier (BBB)-protective effects by concurrently targeting multiple cellular signaling pathways in cerebral ischemia-reperfusion injury. Thus, those compounds are potential to be one-drug-multi-target agents as combined therapy with t-PA for ischemic stroke. In this review article, we summarize current progress about molecular targets involving in t-PA-mediated HT and neurotoxicity in ischemic brain injury. Based on these targets, we select 23 promising compounds from currently available literature with the bioactivities simultaneously targeting several important molecular targets. We propose that those compounds merit further investigation as combined therapy with t-PA. Finally, we discuss the potential drawbacks of the natural compounds&#039; studies and raise several important issues to be addressed in the future for the development of natural compound as an adjunct therapy.

Phenolic Melatonin-Related Compounds: Their Role as Chemical Protectors against Oxidative Stress

There is currently no doubt about the serious threat that oxidative stress (OS) poses to human health. Therefore, a crucial strategy to maintain a good health status is to identify molecules capable of offering protection against OS through chemical routes. Based on the known efficiency of the phenolic and melatonin (MLT) families of compounds as antioxidants, it is logical to assume that phenolic MLT-related compounds should be (at least) equally efficient. Unfortunately, they have been less investigated than phenols, MLT and its non-phenolic metabolites in this context. The evidence reviewed here strongly suggests that MLT phenolic derivatives can act as both primary and secondary antioxidants, exerting their protection through diverse chemical routes. They all seem to be better free radical scavengers than MLT and Trolox, while some of them also surpass ascorbic acid and resveratrol. However, there are still many aspects that deserve further investigations for this kind of compounds.

Investigation of Epidermal Growth Factor, Tumor Necrosis Factor-alpha and Thioredoxin System in Rats Exposed to Cerebral Ischemia

Background: Thioredoxin reductase (TrxR), epidermal growth factor (EGF) and tumor necrosis factor-α (TNF-α) have neuroprotective/neurotoxic effects in cerebral ischemia. We aimed to investigate the TrxR activity, EGF and TNF-α levels in cerebral ischemic, sham-operated and non-ischemic rat brains.

Methods: Sprague-Dawley rats divided into three groups. Rats in control group were not subjected to any of treatments and their brains were removed under anesthesia. Middle cerebral arters were exposed but not occluded for the sham-operated rats. Animals were subjected to permanent middle cerebral arter occlusion (MCAO) in MCAO-operated group. The rats were decapitated at 16 hours (h), 48 h and 96 h after sham operation and focal cerebral ischemia. TrxR activities, EGF and TNF-α levels were measured in ischemic and non-ischemic hemispheres for all groups.

Results: In group MCAO, TrxR activities were significantly low at 48 h in ischemic hemisphere in comparison to control. After the 48 h, a remarkable increase was observed at 96 h. EGF and TNF-α levels were substantially high at 96 h in group MCAO of ischemic brain.

Conclusion: TrxR activity was reduced by oxidative stress which was formed by ischemia. EGF levels increased to exhibit neurotrophic and neuroprotective effects. After ischemia, TNF-α levels increased as a response to the tissue damage. Further studies with a higher number of experimental subjects and shorter or longer periods such as from first 30 minutes up to 3 months may be more informative to show the time-dependent variations in TrxR, EGF and TNF-α in cerebral ischemic injury.

Protective effect of Edaravone against hypoxia-induced cytotoxicity in osteoblasts MC3T3-E1 cells

Edaravone is a newly developed clinical medicine for the treatment of acute cerebral infarction. Reduced blood supply to bones (hypoxia) has been involved in the pathological development of osteoporosis. In this study, we investigated the effect of Edaravone and its latent mechanism on hypoxia-induced cell toxicity in MC3T3-E1 cells. Cell viability was determined by the 3-(4,5-dimethyl-thiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Intracellular reactive oxygen species (ROS) and nitric oxide (NO) were determined by the fluorescence dyes 2',7'-dichlorofluorescein diacetate (DCFH-DA) and 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate (DAF-FM DA), respectively. mRNA and proteins were determined by real-time polymerase chain reaction and Western blot analysis, respectively. Edaravone significantly restored the hypoxia-induced reduction of MC3T3-E1 cell viability and inhibited lactate dehydrogenase release. In addition, we found that Edaravone inhibits the generation of ROS and NO. Hoechst staining results indicated that the nuclear condensation characteristic of apoptosis was increased in MC3T3-E1 cells after hypoxia exposure, which was significantly suppressed by Edaravone treatment. Mechanistically, we found that Edaravone markedly reduced the expression of cleaved caspase-3 and blunted the release of cytochrome c. These findings strongly suggested that Edaravone suppresses hypoxia-induced cytotoxicity in MC3T3-E1 cells. The pleiotropic effects of Edaravone on hypoxia exposure in osteoblasts suggest potential antiosteoporosis mechanisms of Edaravone.