Chemical reactivity and uses of 1-phenyl-3-methyl-5-pyrazolone (PMP), also known as edaravone

1-Phenyl-3-methyl-5-pyrazolone is a reagent, known as PMP, used to derivatize monosaccharides for the study of polysaccharides composition and structure, and for the dosage of carbohydrates in complex media. The same molecule is also known as edaravone, a drug approved for the treatment of stroke and amyotrophic lateral sclerosis. It is also a reactive molecule susceptible to form stable adducts with aromatic aldehydes, such as formylpterin and vanillin. In addition, the molecule serves as a scaffold to design of edaravone analogs and drug conjugates, with various pharmacological properties (antioxidant, anticancer, antiviral). We have analyzed the multiple usages of PMP/edaravone to highlight the reactivity of the molecule and its wide range of applications. This phenyl-pyrazolone compound, considered by many as a biochemical reagent and by other as a clinically useful drug, has not yet revealed the full extent of its capacities and benefits.     

依达拉奉对MPP+处理的PC12细胞线粒体融合和分裂平衡的保护作用

本文旨在探讨依达拉奉(edaravone, Eda)对帕金森病细胞模型线粒体融合、分裂动态平衡的作用及机制。用500μmol/L1-甲基-4-苯基吡啶离子(1-methyl-4-phenylpyridinium, MPP^+)处理PC12细胞建立帕金森病细胞模型,采用噻唑蓝(MTT)比色法检测不同浓度Eda对MPP^+处理的PC12细胞存活率的影响,用激光共聚焦显微镜检测线粒体形态,用Western blot检测线粒体融合与分裂相关蛋白OPA1、MFN2、DRP1和Fis1的表达变化。结果显示,预先加入不同浓度的Eda能减轻MPP^+处理的PC12细胞损伤,作用呈一定的量效关系;经MPP^+处理48 h,PC12细胞线粒体出现碎片化,OPA1和MFN2蛋白表达下调,DRP1和Fis1蛋白表达上调,而Eda预处理能逆转PC12细胞的上述变化,但对Fis1的蛋白表达没有影响。以上结果提示,Eda可上调OPA1和MFN2的蛋白表达,下调DRP1的表达,从而抑制线粒体碎片化,发挥神经细胞线粒体保护作用。     

依达拉奉治疗急性脑出血的临床疗效及对血浆MMP-9水平的影响

目的：观察依达拉奉治疗急性脑出血的临床疗效和对血浆基质金属蛋白酶-9（MMP-9）水平的影响。方法：60例急性脑出血患者随机分为治疗组和对照组各30例。对照组给予常规治疗,治疗组在对照组治疗基础上加用依达拉奉,并在治疗后24h内和14d进行神经功能缺损评分及血浆MMP-9水平测定。结果：治疗组神经功能缺损评分、血浆MMP-9水平较对照组降低（P〈0.05、P〈0.01）。结论：依达拉奉可改善急性脑出血患者神经功能,可能与降低MMP-9水平有关。     

Beneficial effects of edaravone, a novel antioxidant, in rats with dilated cardiomyopathy

Edaravone, a novel antioxidant, acts by trapping hydroxyl radicals, quenching active oxygen and so on. Its cardioprotective activity against experimental autoimmune myocarditis (EAM) was reported. Nevertheless, it remains to be determined whether edaravone protects against cardiac remodelling in dilated cardiomyopathy (DCM). The present study was undertaken to assess whether edaravone attenuates myocardial fibrosis, and examine the effect of edaravone on cardiac function in rats with DCM after EAM. Rat model of EAM was prepared by injection with porcine cardiac myosin 28 days after immunization, we administered edaravone intraperitoneally at 3 and 10 mg/kg/day to rats for 28 days. The results were compared with vehicle-treated rats with DCM. Cardiac function, by haemodynamic and echocardiographic study and histopathology were performed. Left ventricular (LV) expression of NADPH oxidase subunits (p47(phox), p67(phox), gp91(phox) and Nox4), fibrosis markers (TGF-β(1) and OPN), endoplasmic reticulum (ER) stress markers (GRP78 and GADD 153) and apoptosis markers (cytochrome C and caspase-3) were measured by Western blotting. Edaravone-treated DCM rats showed better cardiac function compared with those of the vehicle-treated rats. In addition, LV expressions of NADPH oxidase subunits levels were significantly down-regulated in edaravone-treated rats. Furthermore, the number of collagen-III positive cells in the myocardium of edaravone-treated rats was lower compared with those of the vehicle-treated rats. Our results suggest that edaravone ameliorated the progression of DCM by modulating oxidative and ER stress-mediated myocardial apoptosis and fibrosis.     

Edaravone protects against MPP+ -induced cytotoxicity in rat primary cultured astrocytes via inhibition of mitochondrial apoptotic pathway

Edaravone (Eda) is a potent scavenger of hydroxyl radicals and has been demonstrated to be beneficial for patients with acute ischemic stroke. This study was set out to investigate whether Eda protect against MPP(+)-induced cytotoxicity in rat primary cultured astrocytes. The results showed that pre-treatment with Eda inhibited astrocytic apoptosis and lactate dehydrogenase release induced by MPP(+) (200 microM). Further study revealed that Eda prevented GSH depletion, down-regulated mRNA expressions of NADPH oxidase membrane subunit gp91 and membrane-translocated subunit p47, and prevented the decreases of state 3 respiration respiration and respiratory control ratio induced by MPP(+), and thereby inhibited reactive oxygen species production evoked by MPP(+). Moreover, Eda could ameliorate mitochondrial respiratory function, restrain, and prevent mitochondrial membrane potential loss induced by MPP(+). Consequently, Eda inhibited releases of cytochrome c and apoptosis-inducing factor induced by MPP(+). Taken together, these findings reveal for the first time that Eda protects against MPP(+)-induced astrocytic apoptosis via decreasing intracellular reactive oxygen species level and subsequently inhibiting mitochondrial apoptotic pathway. The antiapoptosis effects of Eda on astrocytes may provide a new perspective on neuroprotective therapy.     

Platelet activating factor induces transient blood‐brain barrier opening to facilitate edaravone penetration into the brain

The blood–brain barrier (BBB) greatly limits the efficacy of many neuroprotective drugs' delivery to the brain, so improving drug penetration through the BBB has been an important focus of research. Here we report that platelet activating factor (PAF) transiently opened BBB and facilitated neuroprotectant edaravone penetration into the brain. Intravenous infusion with PAF induced a transient BBB opening in rats, reflected by increased Evans blue leakage and mild edema formation, which ceased within 6 h. Furthermore, rat regional cerebral blood flow (rCBF) declined acutely during PAF infusion, but recovered slowly. More importantly, this transient BBB opening significantly increased the penetration of edaravone into the brain, evidenced by increased edaravone concentrations in tissue interstitial fluid collected by microdialysis and analyzed by Ultra‐performance liquid chromatograph combined with a hybrid quadrupole time‐of‐flight mass spectrometer (UPLC‐MS/MS). Similarly, incubation of rat brain microvessel endothelial cells monolayer with 1 μM PAF for 1 h significantly increased monolayer permeability to ¹²⁵I‐albumin, which recovered 1 h after PAF elimination. However, PAF incubation with rat brain microvessel endothelial cells for 1 h did not cause detectable cytotoxicity, and did not regulate intercellular adhesion molecule‐1, matrix‐metalloproteinase‐9 and P‐glycoprotein expression. In conclusion, PAF could induce transient and reversible BBB opening through abrupt rCBF decline, which significantly improved edaravone penetration into the brain.

     

依达拉奉治疗急性脑出血的临床疗效及对血浆MMP-9水平的影响

目的:观察依达拉奉治疗急性脑出血的临床疗效和对血浆基质金属蛋白酶-9(MMP-9)水平的影响。方法:60例急性脑出血患者随机分为治疗组和对照组各30例。对照组给予常规治疗,治疗组在对照组治疗基础上加用依达拉奉,并在治疗后24h内和14d进行神经功能缺损评分及血浆MMP-9水平测定。结果:治疗组神经功能缺损评分、血浆MMP-9水平较对照组降低(P<0.05、P<0.01)。结论:依达拉奉可改善急性脑出血患者神经功能,可能与降低MMP-9水平有关。     

Tetranor PGDM analyses for the amyotrophic lateral sclerosis: positive and simple diagnosis and evaluation of drug effect

Amyotrophic lateral sclerosis (ALS) is a late-onset, progressive motor neuronal degenerative disease occurring as sporadically and as a familial disorder. The patients with ALS typically become progressively paralyzed and develop respiratory failure that eventually leads to death within 3–5 years. For this disease, there is no effective diagnostic method and also drug. This report describes a simple and useful diagnostic biomarker for ALS. Our findings suggest that the combination analysis of a metabolite of prostaglandin D2, 11,15-dioxo-9-hydroxy-,2,3,4,5-tetranorprostan-1,20-dioic acid (tetranor PGDM and tPGDM) with creatinine is the diagnostic approach for ALS with high accuracy. tPGDM has the potential to be an important diagnostic tool in the pre-symptomatic stages and progression evaluation of ALS, and also to be a biomarker for the evaluation of drug effect.     

The therapeutic effects of edaravone on collagen-induced arthritis in rats

Current research suggests that synovial phagocytic cells remove excessive amounts of free oxygen radicals (reactive oxygen species [ROS]), thereby preventing damage to synovial tissues. Moreover, ROS may affect the expression of growth arrest and DNA damage inducible α (GADD45A), thus further promoting the activation of synovial fibroblasts. Male adult rats were assessed for progression of collagen-induced arthritis (CIA) using a macroscopic arthritis scoring system of the hind paws and by measuring the changes in the rat's body weight, and activity level before and after diagnosis of CIA. Rats were intraperitoneally injected twice daily with edaravone at doses of 3, 6, and 9 mL/kg. Samples were taken at 2, 4, and 6 weeks, respectively. Edaravone was found to significantly reduce macroscopic arthritis and microscopic pathology scores in CIA rats. The concentration of endothelial nitric oxide synthase-6, glutathione, and heme oxygenase-1 in the serum of rats decreased, as was the production of ROS around the synovium and inflammatory factors. Moreover, ROS-1 increased the expression of the nuclear factor-κB (NF-κB) p65 protein by altering the expression level of GADD45A, causing aggravation of tissue damage. Edaravone also significantly improved the physiological condition of CIA rats, including appetite, weight changes, and loss of fur, as well as limb mobility. We believe that edaravone acts to reduce the expression of NF-ĸB p65 by clearing ROS, which causes reduced expression of GADD45A, and subsequently reduces the level of apoptosis and inflammatory response proteins, thereby reducing the symptoms of CIA. We, therefore, propose that edaravone is an effective option for clinical treatment of rheumatic arthritis.     

依达拉奉联合尤瑞克林治疗急性脑梗塞的疗效观察

目的:观察依达拉奉联合尤瑞克林治疗急性脑梗塞的疗效及安全性。方法:将84例急性脑梗塞患者随机分为2组,对照组予依达拉奉30 mg加入生理盐水100 mL静脉滴注,每日两次。观察组在上述基础上另予尤瑞克林0.15 PNA加入生理盐水250mL中静脉滴注,每天一次。两组疗程均为2周。观察两组患者的神经功能缺损评分、疗效与不良反应。结果:两组患者神经功能缺损评分均较治疗前明显改善(P<0.01),观察组评分明显低于对照组(P<0.01)。观察组临床总有效率达97.6%,明显高于对照组的57.1%(P<0.01)。两组不良反应发生率无统计学差异。结论:达拉奉联合尤瑞克林治疗急性脑梗塞临床疗效好,安全性高。