MMP-9-related brain hemorrhage

Edaravone has effects on glutamate toxicity that are both therapeutic and preventative. Edaravone pretreatment decreased glutamate's toxicity to SGN. Edaravone lessens necrosis and apoptosis brought on by glutamate. These alterations were reverted to near-normal levels by pretreatment with 500 μM edaravone. Edaravone's protective action against glutamate-induced SGNs cell apoptosis is associated with the Bcl-2 protein family and the PI3K/Akt pathway [4].

In cerebral ischemia, edaravone reduces neuronal damage and prevents endothelium damage to have neuroprotective effects. The helpful NOS that can save an ischemic stroke is increased when eNOS is present, but nNOS and iNOS—the toxic NOS—are decreased when edaravone is present. Pretreatment with edaravone decreases hemorrhagic episodes and post-reperfusion cerebral edema brought on by thrombolytic therapy [1]. The infarct size was greatly reduced by edaravone; rats in the edaravone group had an average infarct size of 227.6 mm3, which was significantly smaller than rats in the control group (264.0 mm3). Additionally, the post-ischemic bleeding volume was decreased by edaravone therapy (53.4 mm3 in edaravone-treated rats against 53.4 mm3 in the control group). 176.4 millimeters). Furthermore, rats treated with edaravone had a decreased ratio of bleeding volume to infarct volume (23.5%) compared to rats not treated (63.2%) [2]. The corpus callosum, germinal matrix, and cerebral cortex of rats given Edaravone (20 mg/kg) showed decreased astrocyte activity (glial fibrillary acidic protein) and apoptotic cells (caspase-3) [3].

Detection of Apoptosis and Necrosis by Ho.33342 and Propidium Iodide (PI) Double Staining [4]
SGNs were incubated with glutamate with or without edaravone (500 μM). Control cells were without any treatment. Cells were washed twice by PBS, fixed with 95% alcohol for 10 min, and then stained by Ho.33342 (10 mg/mL) and PI (50 mg/mL) at 37°C for 30 min. Morphological changes were examined by fluorescence microscope under green light (515–560 nm) and ultraviolet (UV) light (340–380 nm), respectively. At least 500 cells were counted in 5 randomly selected fields per group. All treatments were repeated three times.

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Detection of GSH Content, SOD Activity, and MDA Level by Spectrophotometer[4]
SGNs were incubated with 2 mM glutamate for 10 min with or without the pretreatment of 500 μM edaravone 2 h ahead. Control cells were without any treatment. Then cells were washed twice with ice-cold PBS, sonicated, and harvested for the following assays. Intracellular GSH content, SOD activity, and MDA level in all groups were measured by commercial assay kits according to the manufacturer's instructions. OD values at optimal wavelengths were measured using spectrophotometer and the relative levels comparing with control cells were calculated. All experiments were repeated three times.

Drug Treatment [4]
SGNs (1.0 × 105/mL) subcultured in 96-well or 24-well plate were treated with 2 mM glutamate for 10 minutes. Then the medium was replaced by normal DMEM. Different concentrations of edaravone were added to the medium either 20 min before or 2 h, 6 h, and 12 h after glutamate treatment. All the doses and time points were determined by preliminary experiments (data not shown).

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Assessment of Cell Viability by MTT and Trypan Blue Staining[4]
Cell viability was quantified by MTT assay and trypan blue staining. MTT (5 mg/mL, 20 μL) was added to each well and incubated for 4 h at 37°C after the drug treatments as described above. The medium was removed and the cell pellet was dissolved in DMSO. Then, the optical density (OD) values were measured at 570 nm using an ELISA reader. All experiments were repeated three times. Cell relative viability was calculated according to the following formula:
Cell  relative  viability  (%)=ODexperimentODcontrol×100%.
ODblank was used as zero.
In trypan blue staining, SGNs were stained with 0.4% trypan blue for 5 min after the drug treatments as described above. Pictures were taken by microscope and trypan blue positive and negative cells were counted afterwards. Cell survival rate was defined as the percentage of negative cells.

Absorption, Distribution and Excretion
One study investigated the absorption of edaravone in healthy adults, who either received a single oral (105 mg/mL) or intravenous (60 mg/60 min) dose. The mean Cmax (CV%) and Tmax were 1656 (44.3) ng/mL and 0.5 hours, respectively, following oral administration. The absolute oral bioavailability is about 57% because of first-pass metabolism. The mean Cmax (CV%) and Tmax were 1253 (18.3) ng/mL and one hour, respectively, following intravenous administration. When intravenously administered, the maximum plasma concentration (Cmax) of edaravone was reached by the end of infusion. The Cmax and area under the concentration-time curve (AUC) of edaravone increases more than dose-proportional over the dose range of 30 to 300 mg. Edaravone does not accumulate in plasma with once-daily or multiple-dose administration. The Cmax and AUC decreased when the oral suspension formulation of edaravone was administered with a high-fat meal.
In Japanese and Caucasian healthy volunteer studies, edaravone was excreted mainly in the urine as its glucuronide conjugate (60-80% of the dose up to 48 hours). Approximately 6-8% of the dose was recovered in the urine as the sulfate conjugate, and <1% of the dose was recovered in the urine as the unchanged drug. _In vitro_ studies suggest that the sulfate conjugate of edaravone is hydrolyzed back to edaravone, which is then converted to the glucuronide conjugate in the kidney before excretion into the urine.
After intravenous administration, edaravone has a mean volume of distribution of 63.1 L, suggesting substantial tissue distribution. Edaravone has an apparent volume of distribution of 164 L following oral administration. Edaravone readily crosses the blood-brain barrier.
Following intravenous administration, the total clearance of edaravone is estimated to be 35.9 L/h. The apparent total clearance of edaravone is estimated to be 67.9L/h following oral administration.

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Metabolism / Metabolites
The metabolites of edaravone have not been fully characterized. Edaravone is metabolized to a sulfate conjugate and a glucuronide conjugate, which are not pharmacologically active. The glucuronide conjugation of edaravone involves multiple uridine diphosphate glucuronosyltransferase (UGT) isoforms (UGT1A1, UGT1A6, UGT1A7, UGT1A8, UGT1A9, UGT1A10, UGT2B7, and UGT2B17). In human plasma, edaravone is mainly detected as the sulfate conjugate, which is presumed to be formed by sulfotransferases. Oral edaravone results in 1.3- and 1.7-fold higher exposures for both sulfate and glucuronide metabolites, respectively, when compared to intravenously-administered edaravone because of first-pass metabolism.

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Biological Half-Life
The mean terminal elimination half-life of edaravone is approximately 4.5 to nine hours. The half-lives of its metabolites range from three to six hours.

Hepatotoxicity
Serum aminotransferase elevations occur in a small proportion of patients on edaravone therapy, but the frequency, timing of onset, duration and severity of these elevations has not been defined. The rates of abnormal liver tests during edaravone therapy were said to be similar to those during placebo treatment. Most elevations resolved spontaneously, and there were no reports of drug discontinuation for serum enzyme elevations. Clinically apparent liver injury due to edaravone was not reported in the prelicensure trials and has not been reported with subsequent clinical use of edaravone, but the numbers of patients treated have been few. Thus, clinically apparent liver injury from edaravone must be rare if it occurs at all.
Likelihood score: E (unlikely cause of clinically apparent liver injury).

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Protein Binding
Edaravone is 92% bound to human serum proteins, mainly to albumin, with no concentration dependence in the range of 0.1 to 50 micromol/L.

[1]. Neuroprotective effects of edaravone: a novel free radical scavenger in cerebrovascular injury. CNS Drug Rev, 2006. 12(1): p. 9-20.

[2]. Edaravone, a free radical scavenger, attenuates cerebral infarction and hemorrhagic infarction in rats with hyperglycemia. Neurol Res, 2013.

[3]. Edaravone reduces astrogliosis and apoptosis in young rats with kaolin-induced hydrocephalus. Childs Nerv Syst. 2016 Dec 17. [Epub ahead of print].

[4]. Protective Effect of Edaravone on Glutamate-Induced Neurotoxicity in Spiral Ganglion Neurons. Neural Plast. 2016;2016:4034218. Epub 2016 Nov 10.

1-phenyl-3-methyl-5-pyrazolone appears as white to off-white powder or crystals. (NTP, 1992)
Edaravone is a pyrazolone that is 2,4-dihydro-3H-pyrazol-3-one which is substituted at positions 2 and 5 by phenyl and methyl groups, respectively. It has a role as a radical scavenger and an antioxidant.
Edaravone is a free radical scavenger and neuroprotective agent with antioxidant properties. It has three tautomers. Edaravone works to scavenge reactive oxygen species, which have been implicated in neurological disorders, such as amyotrophic lateral sclerosis (ALS) and cerebral ischemia. The intravenous formulation of edaravone was first approved in Japan in 2001 for the treatment of acute ischemic stroke. It was later approved for the treatment of amyotrophic lateral sclerosis (ALS) in Japan and South Korea in 2015, followed by the FDA approval in May 2017 and Health Canada approval in October 2018. The oral suspension formulation of edaravone was approved by the FDA in May 2022 and by Health Canada in November 2022. Edaravone was initially granted orphan designation by the European Medicines Agency on June 19, 2015 and was under regulatory review in Europe. However, the drug manufacturer, Mitsubishi Tanabe Pharma, withdrew the Marketing Authorization Application (MAA) for edaravone from the European market on May 24, 2019, in response to the request made by the Committee for Medicinal Products for Human Use (CHMP) for a long-term study demonstrating the long-term efficacy and safety of edaravone. Edaravone was also investigated in other disorders, such as Alzheimer's disease, neuropathic pain, and ischemia-induced nerve injury.
Edaravone is a free radical scavenger and neuroprotective agent used for therapy of amyotrophic lateral sclerosis. Edaravone is associated with a low rate of serum aminotransferase elevations during therapy but has not been linked to instances of clinically apparent, acute liver injury.
Edaravone has been reported in Homo sapiens with data available.
An antipyrine derivative that functions as a free radical scavenger and neuroprotective agent. It is used in the treatment of AMYOTROPHIC LATERAL SCLEROSIS and STROKE.

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Drug Indication
Edaravone is indicated for the treatment of amyotrophic lateral sclerosis (ALS) in the US and Canada. It is also indicated to treat acute ischemic stroke in Japan.
Treatment of amyotrophic lateral sclerosis
Treatment of amyotrophic lateral sclerosis

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Mechanism of Action
Oxidative stress and reactive oxygen species (ROS) production have been implicated in various neurological disorders, such as amyotrophic lateral sclerosis (ALS) and cerebral ischemia. Oxidative stress caused by excess ROS damages endothelial cells in the cerebral vasculature as well as neuronal cell membranes, leading to neuronal cell death. Edaravone is a free radical scavenger that scavenges and suppresses the generation of hydroxyl radicals and peroxynitrite radicals. The exact mechanism of action of edaravone in ALS has not been fully elucidated; however, edaravone is thought to mediate therapeutic effects via its antioxidant properties. Since oxidative stress has been implicated in the pathophysiology of ALS and cerebral ischemia, inhibiting lipid peroxidation, suppressing endothelial cell damage induced by lipid peroxides, and scavenging free radicals may lead to neuroprotective effects. Edaravone has no effect on superoxide production. It is suggested that edaravone may also possess anti-inflammatory properties, as it inhibited neutrophil activation and suppressed inducible nitric oxide synthase (iNOS) and neuronal nitric oxide synthase (nNOS) expression in animal models. It was also shown to ameliorate ROS-induced inflammatory oxidative stress after ischemic brain reperfusion.

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Pharmacodynamics
Edaravone works to delay the disease progression of neurological disorders such as ischemic stroke and ALS by limiting the extent of neuronal damage or death.

C10H10N2O

174.2

174.079

C, 68.95; H, 5.79; N, 16.08; O, 9.18

89-25-8

Edaravone-d5;1228765-67-0

4021

Light yellow to yellow solid

1.2±0.1 g/cm3

333.0±11.0 °C at 760 mmHg

126-128 °C(lit.)

155.2±19.3 °C

0.0±0.7 mmHg at 25°C

1.606

0.44

0

2

1

13

241

0

O=C1CC(C)=NN1C1C=CC=CC=1

QELUYTUMUWHWMC-UHFFFAOYSA-N

InChI=1S/C10H10N2O/c1-8-7-10(13)12(11-8)9-5-3-2-4-6-9/h2-6H,7H2,1H3

5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one

MCI-186; NCI-C03952; MCI 186; NSC 12; MCI186; Radicut; trade name: Radicava; Methylphenylpyrazolone; Norantipyrine; Norphenazone; Phenylmethylpyrazolone; Arone

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Solubility in Formulation 1: ≥ 2.5 mg/mL (14.35 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (14.35 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (14.35 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)