Neuroprotective effect of ONO-1078, a leukotriene receptor antagonist, on transient global cerebral ischemia in rats

AIM: To determine whether ONO-1078 {pranlukast, 4-oxo-8-[p-(4-phenylbutyloxy)benzoyl-amono]-2-(tetrazol-5-yl)-4H-1-benzopyran hemihydrate}, a potent leukotriene receptor antagonist, possesses a neuroprotective effect on global cerebral ischemia in rats, and to explore its possible mechanism of action. METHODS: Transient global cerebral ischemia was induced by four-vessel occlusion for 10 min and followed by 72-h reperfusion. ONO-1078 (0.03-0.3 mg/kg) and edaravone (MCI-186, 3-methyl-1-phenyl-2-pyrazolin-5-one, a neuroprotective agent) 10 mg/kg were ip injected 30 min before ischemia and 1 h after reperfusion, and once a day afterward. Neurological outcome was evaluated before ischemia and 24, 48, 72 h after reperfusion. Neuron density, the expressions of N-methyl-Daspartate (NMDA) receptor subunit proteins (NR1, NR2A, NA2B) and vascular cell adhesion molecule 1(VCAM-1) in the cerebral cortex and hippocampus were measured at 72 h after reperfusion. RESULTS: ONO-1078 (0.1, 0.3 mg/kg) and edaravone (10 mg/     

ONO-1078 reduces NMDA-induced brain injury and vascular cell adhesion molecule-1 expression in rats

Aim: To determine whether ONO-1078 (pranlukast), a potent cysteinyl leukotriene receptor 1 （CysLT1） antagonist, has an effect on N-methyl-D-aspartate (NMDA)-induced brain injury and vascular cell adhesion molecule-1 (VCAM-1) expression in rats. Methods: Brain injury was induced by direct microinjection of NMDA (0.3μmol in 1μL of sterile 0.1mol/L PBS, pH 7.4) into the cerebral cortex. The lesion volume (area), brain edema and neuron density were assessed by an image analyzer and the expression of VCAM-1 in the cortex was detected by Western blot 24h after NMDA injection. ONO-1078(0.03, 0.1, or 0.3mg/kg) and edaravone (MCI-186, 10mg/kg), a neuroprotective agent, were ip injected 30min before and after NMDA injection. Results: NMDA microinjection produced well-defined focal lesions (Figure 1) dose- and time-dependently. ONO-1078(0.1, 0.3mg/kg) and edaravone (10mg/kg) decreased the total lesion volume, lesion area and brain edema induced by NMDA. Furthermore, ONO-1078 (0.1, 0.3mg/kg) significantly inhibited the enhanced expression of VCAM-1 in the injured cortices, but edaravone did not have this effect. Conclusion: CysLT1 receptor antagonist ONO-1078 attenuates NMDA-induced brain damage in rats, and this might relate to the attenuation of NMDA receptor-dependent neurotoxicity and the inhibition of the upregulation of VCAM-1 expression.     

Therapeutic effect of pranlukast, a cysteinyl leukotriene receptor antagonist, on focal cerebral ischemia in mice

AIM: To determine whether pranlukast (ONO-1078 ), a cysteinyl leukotriene receptor antagonist, possesses therapeutic effect when administered after focal cerebral ischemia in mice. METHODS： Persistent focal cerebral ischemia was induced by middle cerebral artery occlusion, pranlukast and edaravone, a positive control drug, were ip injected 1, 6 and     

Competitive binding of postsynaptic density 95 and Ca^2＋-calmodulin dependent protein kinase Ⅱ to N-methyl-D-aspartate receptor subunit 2B in rat brain

AIM: To investigate the interactions among postsynaptic density 95 (PSD-95), Ca^2 -calmodulin dependent protein kinase Ⅱα (CaMKⅡα), and N-methyl-D-aspartate receptor subunit 2B (NR2B) during ischemia and reperfusion in hippocampus of rats. METHODS: Brain ischemia was induced by four-vessel occlusion procedure in rats. Immunoprecipitation and immunoblotting were performed to study the interactions and phosphorylation of proteins. The association-dissociation of PSD-95 and CaMKⅡα to and from N-methyl-D-aspartate (NMDA) receptor induced by ischemia and reperfusion and the effects of 1-[N,O-bis-(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenyl-piperazine (KN-62, a selective inhibitor of CaMKⅡ) on these protein interactions were investigated. Coimmunoprecipitation and immunoblotting were performed for the studies of interactions among proteins. RESULTS: The alternations of the binding level of PSD-95 and CaMKⅡα to NR2B during ischemia and reperfusion demonstrated the negative correlation to each other. Pre-administration of KN62 through both cerebral ventricles inhibited the 10min ischemia-induced increase of the binding of PSD-95 to NR2B and, on the contrary, promoted the binding of CaMKⅡα to NR2B. CONCLUSION: PSD-95 competes with CaMKⅡ to bind to NR2B during ischemia and reperfusion in rat hippocampus.     

Pranlukast dose-and time-dependently protects against ischemic neuronal damage in the rat hippocampus

Objective Our previous studies showed that the neuroprotective effect of pranlukast,a cysteinyl leukotriene receptor-1(CysLT1)antagonist,on global cerebral ischemia in rats.This study was performed to evaluate dose-and time-dependent properties of pranlukast on CA1 neuron loss following transient global ischemia in rats.Methods Brain injury was induced by an improved four-vessel occlusion(4-VO)in rats.pranlukast(0.03-0.30 mg·kg-1)was injected intraperitoneally either as multiple doses(before or after ischemia)or as a single dose(30 min before ischemia),respectively.Physiological variables were monitored and neuron count was measured by computer-assisted imaging.Results The 4-VO model produced continuing postischemic neuronal death in CA1 region.Administration of pranlukast(0.1 and 0.3 mg·kg-1,30 min before ischemia and 1,24,48 and 72 h after ischemia)markedly reduced CA1 death.Treatment with a single dose of pranlukast(0.1 mg·kg-1,30 min before ischemia)also resulted in a significant increase in the number of healthy CA1 neurons at 3 days.Of interest is the finding that pranlukast(0.1 mg·kg-1)rescued CA1 neurons from ischemic death even when treatment was delayed until 30 min or 1 h after ischemia.Conclusions The present study confirms pranlukast has a dose-and time-dependent cerebroprotective effects on CA1 neuron loss following transient global ischemia in rats,with an effective dose range of 0.1-0.3 mg·kg-1 and a therapeutic window of 1 h.These findings further support the therapeutic potential of CysLT1 receptor antagonists in the treatment of global cerebral ischemia.     

白三烯拮抗剂ONO-1078对小鼠局灶性脑缺血的保护作用

AIM　To determine whether ONO-1078 {pranlukast, 4-oxo-8-［p-(4-phenylbutyloxy) benzoyl-amino]-2-(tetrazol-5-yl)-4H-1-benzopyran hemihydrate}, a potent leukotriene antagonist, has protective effect on focal cerebral ischemia in mice. METHODS　Focal cerebral ischemia was induced by permanent middle cerebral artery (MCA) occlusion in mice. ONO-1078 (0.01, 0.05, 0.10 mg·kg^-1), dexamethasone (0.5 mg·kg^-1), nimodipine (0.2 mg·kg^-1) or saline (control) were injected ip once daily for 3 days, and 30 min before MCA occlusion. Twenty-four hours after cerebral ischemia, the neurological scores were evaluated, infarct volumes and areas of the right and left cerebral hemispheres were measured by computer imaging analysis. RESULTS　ONO-1078, dexamethasone and nimodipine reduced the neurological scores. ONO-1078 and dexamethasone reduced the ratio of right/left hemisphere area, indicating inhibition of brain edema, while nimodipine showed no effect. ONO-1078 dose-dependently reduced infarct size, and dexamethasone and nimodipine showed the same effect. CONCLUSION　ONO-1078 showed protective effect on focal cerebral ischemia. This may represent a novel approach to the treatment of acute cerebral ischemia.     

银杏叶提取物对大鼠脑缺血再灌时脑电图的作用

AIM:To test the effect of Grinkgo biloba leaf extract on electroencephalography(EEG) during cerebral ischemia and reperfusion.METHODS:Based on the quantitative analysis of EEG using the fast Fourier transform(FFT), the effect of Ginkgo biloba extract(GbE) on rat EEG was surveyed in the model of middle cerebral artery (MCA) occlusion and global cerebral ischemia.Results:In the golbal cerebral ischemia,GbE 8 and 16 mg/kg could accelerate the recovery of EEG after reperfusion,and GbE4 mg/kg had the same effect but much weaker,In the MCA occlusion model GbE 16 and 32 mg/kg greatly supressed the drop of power spectrum of EEG.CONCLUSION:GbE could mitigate the cerebral damage caused by ischemia.     

Histidine protects against long-term injury after cerebral ischemia by promotion of astrocytes migration and inhibition of glial scar formation

OBJECTIVE To study histamine’s effect on longterm injuryafter cerebral ischemia,including on glial scar formation.METHODS After 90 min of transient middle cerebral artery occlusion(tMCAO),histidine with dose combination,500500 mg·kg-1,1000-500 mg·kg-1,1000-1000 mg·kg-1,10000 mg·kg-1(the first week and the later weeks were divided as two phases),was given to SD rats at 0 h,6 h and every other days after reperfusion.28 and 56 d after reperfusion,rats were evaluated with behavioral tests,such as neurological score,fear conditioning test,and Morris water maze.7,14,28,56 days after tMCAO,rats were transcardially perfused by 0.9% cold saline and 4% paraformaldehyde.The dissected brains were then cut into 10 m coronal sections and immunostained for GFAP,Ne-uN,and toluidine blue.Wound-healing assay in vitro was taken to study the promotion ofastrocyte migration provided by histamine.RESULTS After 28 d and 56 d of reperfusion,neurological scores,and learning and memory functions in fear conditioning test and Morris water maze significantly improved in histidine 1000-500 mg·kg-1 group.Meanwhile,the infract area and the glial scar area in this group also decreased.The reactive astrocytes(GFAP positive cells) area were closer to the infract core in the 1000-500 mg·kg-1 group than other groups at 14 d after reperfusion,however,there’s no difference at 7 d after operation.The shape of glial scar’s boundary of 1000-500 mg·kg-1 group was rougher than other groups and the polarizing ratio of astrocytes increased nearly two folds,which suggests the promotion of astrocyte migration by histamine.To our surprise,in the area where astrocyte migrated before,the number of neurons(NeuN positive cells) was up-regulated.In wound-healing assay,histamine promoted astrocyte migration at dose 0.1 μmol·L-1.Its promotion effect can be antagonized by H2 receptor antagonists cimetidine and famotidine,and can be reversed by Rp-cAMP,a PKA antagonist.CONCLUSION Histamine has protective effect on the long-term injury after cerebral ischemia.Its mechanism may involve the promotion of reactive astrocyte migration and subsequently neuron recovery through H2 receptor.     

Effects of β-aescin on apoptosis induced by transient focal cerebral ischemia in rats

ABM: To investigate the effects ofβ-aescin on apoptosis induced by transient focal brain ischemia in rats. METHODS: Rats were pretreated with β-aescin for 7 d and then subjected to brain ischemia/reperfusion (I/R) injury induced by a middle cerebral artery occlusion. After 2 h ischemia and 24 h reperfusion, Hematoxylin-Eosin (HE) staining, in situ end-labeling of nuclear DNA fragmentation (TUNEL) were employed to determine the level of apoptosis. The expressions of caspase-3 and Bcl-2 in the cortex were determined by immunohistochemistry and Western blot. The release of cytochrome c was analyzed by Western blot. RESULTS: The increased numbers of HE- and TUNEL-positive staining cells were significantly observed at 24 h after reperfusion. The immunoreactivity was inhibited by β-aescin (30, 60 mg/kg) (P<0.01 or P<0.05 vs vehicle-treated). After cerebral I/R, cytochrome c was released into the cytosol and caspase-3 was activated, whereas Bcl-2 expression was inhibited. β-Aescin (30, 60 mg/kg) markedly in     

Protective effects of gastrodin on cerebral ischemic transient middle cerebral arterial occlusion-reperfusion

OBJECTIVE To investigate the neuroprotective effects of gastrodin on the cerebral ischemia-reperfusion damage in rats caused by transient middle cerebral arterial occlusion(MCAO),and to explore the protective mechanisms.METHODS The SD rats were administered with gastrodine by gavage once a day for 7 d and the animals were then subjected to right-middle cerebral artery occlusion for 2 h and reperfusion for a week except the sham operation group.Then the neurologic functional scores,the brain infarct size of the rats were analyzed with the neurological severity score(NSS).The ischemic penumbra and central area were distinguished by TTC and HE staining methods.For analyzing the mechanism,the number of neuronal apoptosis was assessed by terminal oxynucleotidyl transferase mediated dUTP biotin nick end labeling(TUNEL).The mRNA level of HIF-1α,Ptgs2,sod1,sod2,Gsk3a was detected by real time RT-PCR,respectively.RESULTS The infarct volume and neurological score in gastrodin-treated groups were lower than those in model group,and gastrodin significantly attenuated the apoptosis and the expression of Gsk3a and Ptgs2 of rats,reduced the mRNA expressions of HIF-1α,sod1 and sod2.CONCLUSION Gastrodin has a neuroprotective effect against cerebral ischemia reperfusion injury.The mechanisms may,at least partly,be due to scavenging free radical,inhibiting neuronal apoptosis.     

白三烯受体拮抗剂ONO—1078对大鼠局灶性脑缺血的神经保护作用

AIM: To determine whether ONO-1078 (pranlukast), a potent leukotriene receptor antagonist, has neuroprotective effect on focal cerebral ischemia in the rat. METHODS: Focal cerebral ischemia was induced by 30 min of middle cerebral artery (MCA) occlusion and followed by 24 h reperfusion. ONO-1078 (0.003-1.0 mg/kg) or vehicle (saline 1 mL/kg) was ip injected 30 min before MCA occlusion and 2 h after reperfusion. The neurological score, infarct volume, neuron density (in cortex, hippocampus, and striatum), brain edema, and albumin exudation around the vessels were determined 24 h after reperfusion. RESULTS: ONO-1078 slightly improved the neurological deficiency, and dramatically decreased infarct volume and neuron loss which showed a bell shaped dose response effect with highest effect at doses of 0.01-0.3 mg/kg. Enlargement of the ischemic hemisphere and albumin exudation were inhibited at doses of 0.01-1.0 mg/kg. CONCLUSION: ONO-1078 has the protective effect on focal cerebral ischemia in rats, which is partially attributed to the inhibition of brain edema. This may represent a novel approach to the treatment of acute cerebral ischemia with cysteinyl leukotriene receptor antagonists.     

白三烯受体拮抗剂ONO-1078对内皮素-1诱导的大鼠局灶性脑缺血的保护作用

目的观察白三烯受体拮抗剂ONO-1078对内皮素-1诱导的大鼠局灶性脑缺血的保护作用。方法向大脑中动脉附近微量缓慢注射内皮素-1(120 pmol,6 μL,>6 min),诱导大鼠局灶性脑缺血模型,在注射内皮素-1前1 h ip ONO-1078(0.1 mg·kg^-1)。观察神经症状、脑水肿程度、脑梗死体积、纹状体和皮层的存活神经元数的变化。结果 脑内微量注射内皮素-1引起动物出现明显神经症状、脑梗死、脑水肿及皮层和纹状体的存活神经元减少。预先ip ONO-1078显著抑制脑水肿,减小脑梗死体积,增加纹状体和皮层的存活神经元数,可减轻神经症状,但无显著意义。结论ONO-1078对内皮素-1诱导的脑缺血损伤有保护作用,白三烯参与了脑缺血后的组织损伤过程。     

半胱氨酰白三烯受体拮抗剂pranlukast对小鼠局灶性脑缺血的治疗作用

目的　观察半胱氨酰白三烯受体拮抗剂pranlukast(ONO 10 78)在小鼠局灶性脑缺血后的治疗作用。方法　采用大脑中动脉阻塞造成小鼠持续性局灶性脑缺血 ,缺血后1、6、2 4h分别给小鼠腹腔注射 pranlukast或依达拉奉 ,观察药物对缺血 2 4、4 8h后的神经功能缺损症状 ,4 8h后的脑梗死体积、两侧大脑半球比值、神经元密度的影响。结果　Pranlukast 0 1、0 2mg·kg-1及依达拉奉 3、10mg·kg-1均能减轻神经症状、减小脑梗死体积、降低缺血侧 /非缺血侧大脑半球比值、减轻海马CA1区、皮层和纹状体的神经元密度降低。结论　Pranlukast脑缺血后给药对脑损伤有治疗作用 ,提示有治疗缺血性脑卒中的临床前景。     

新型神经保护剂TQ0701-2对大鼠脑缺血再灌注损伤的保护作用

目的：研究新型神经保护剂TQ0701-2对大鼠脑缺血再灌注损伤的保护作用。方法：将120只雄性SD大鼠随机分为假手术组、模型组、依达拉奉组（3.0mg/kg）以及TQ0701-2高剂量组（6.0mg/kg）、中剂量组（3.0mg/kg）、低剂量组（1.5mg/kg）。假手术组仅进行手术而不造成缺血状态,其余各组均采用Longa线栓法制备大鼠MCAO模型,在缺血2h后进行再灌注。TQ0701-2三个剂量组和依达拉奉组分别在缺血前30min以及再灌注0、2h尾静脉注射TQ0701-2和依达拉奉,假手术组和模型组则给予等量的生理盐水。再灌注24h后观察大鼠神经功能损伤症状、脑组织梗死率以及病理组织学的改变。结果：模型组大鼠神经功能损伤严重,脑组织梗死率也明显增高（P〈0.01vs假手术组）。与依达拉奉的保护作用相同,TQ0701-2高中低三个剂量均能显著降低MCAO大鼠的神经功能评分和脑组织梗死率（P〈0.01vs模型组）,并且三个剂量的改善作用是随着浓度增大而增强的,具有剂量相关性。另外,TQ0701-2对大鼠脑缺血再灌注所致的神经元变性、坏死也有一定的保护作用。结论：研究表明,依达拉奉衍生物TQ0701-2对大鼠的脑缺血再灌注损伤有明显的神经保护作用。     

Pranlukast, a cysteinyl leukotriene receptor 1 antagonist, protects mice against brain cold injury

We have reported the neuroprotective effect of cysteinyl leukotriene receptor 1 (CysLT1) antagonists on cerebral ischemia. Here, we further determined the protective effect of pranlukast, a CysLT1 receptor antagonist, on brain cold injury in mice. Brains were injured by placing a cooled metal probe on the skull surface for 30 s. We found that pranlukast significantly reduced cold-induced lesion volume (0.3 mg/kg) and the percentage increase in lesioned hemisphere volume (0.03-0.3 mg/kg) 24 h after injury, but did not show any effect 72 h after injury. Pranlukast also significantly inhibited neuron loss 24 h (0.1 mg/kg) and 72 h (0.1-0.3 mg/kg) after injury, and decreased the density of degenerated neurons 24 h (0.01-0.3 mg/kg) and 72 h (0.03-0.3 mg/kg) after injury. In addition, pranlukast (0.1-0.3 mg/kg) significantly reduced endogenous IgG exudation both 24 h and 72 h after injury. Thus, this study indicates the protective effect of pranlukast on brain cold injury.     

NVP-AAM077和Ro25-6981对全脑缺血小鼠海马神经元损伤及BDNF表达的影响

目的探讨N-甲基-D-天冬氨酸受体(NMDA)亚基NR2A和NR2B特异性拮抗剂对脑缺血/再灌注后海马CA1区神经元损伤的不同影响及其可能机制。方法制作三动脉阻断(3-VO)小鼠全脑缺血模型,小鼠随机分为假手术组、脑缺血/再灌注(I/R)对照组、NVP-AAM077(NVP)干预组和Ro25-6981(Ro)干预组;应用Fluoro-JadeB(F-JB)和Nissl染色检测海马神经元变性死亡和存活情况,Western blot对脑源性神经生长因子(BDNF)蛋白表达水平进行定量分析。结果①小鼠全脑缺血12min/再灌注3d后,海马CA1区出现选择性迟发性神经元死亡,NVP干预组增加了缺血所致的海马神经元死亡(P<0.05),而Ro干预组CA1区神经元存活数量明显多于缺血/再灌注组(P<0.01);②NVP干预能明显下调缺血/再灌注所致的海马组织BDNF蛋白表达升高(P<0.01),而Ro干预能明显上调BDNF蛋白的表达(P<0.05)。结论 NMDA受体亚基NR2A和NR2B在小鼠脑缺血/再灌注损伤中具有不同的作用,其机制可能与调节BDNF表达改变有关。     

Montelukast, a cysteinyl leukotriene receptor-1 antagonist, dose- and time-dependently protects against focal cerebral ischemia in mice

Our previous studies showed that cysteinyl leukotriene receptor-1 (CysLT1) antagonist pranlukast has a neuroprotective effect on cerebral ischemia in rats and mice. However, whether the neuroprotective effect of pranlukast is its special action or a common action of CysLT1 receptor antagonists remains to be clarified. This study was performed to determine whether montelukast, another CysLT1 receptor antagonist, has the neuroprotective effect on focal cerebral ischemia in mice, and to observe its dose- and time-dependent properties. Permanent focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). Montelukast was injected intraperitoneally either as multiple doses (once a day for 3 days and 30 min before MCAO) or as a single dose (at 30 min before, 30 min after, or 1 h after MCAO), respectively, and pranlukast and edaravone were used as controls. The neurological deficits, infarct volumes, brain edema, neuron density, and Evans blue extravasation in the brain were determined 24 h after MCAO. Pretreatments with multiple doses or a single dose of montelukast (0.1 and 1.0 mg/kg) before MCAO significantly attenuated all the ischemic insults. Post-treatment with a single dose of montelukast (0.1 and 1.0 mg/kg) at 30 min after MCAO also significantly decreased brain edema and infarct volume, but not neurological deficits. However, post-treatment with a single dose of montelukast at 1 h after MCAO had no significant effect. Pranlukast showed the same effects as montelukast, but edaravone attenuated the ischemic insults only with multiple doses before MCAO. Thus, montelukast has a dose- and time-dependent neuroprotective effect on permanent focal cerebral ischemia in mice, with an effective dose range of 0.1-1.0 mg/kg and a therapeutic window of 30 min. These findings further support the therapeutic potential of CysLT1 receptor antagonists in the treatment of cerebral ischemia at earlier phases.