scholarly journals Neuroprotective Effects of the CRF1 Antagonist R121920 after Permanent Focal Ischemia in the Rat

2001 ◽  
Vol 21 (10) ◽  
pp. 1208-1214 ◽  
Author(s):  
Kenneth B. Mackay ◽  
Haig Bozigian ◽  
Dimitri E. Grigoriadis ◽  
Sarah A. Loddick ◽  
Gail Verge ◽  
...  

The neuroprotective effects of a systemically active, highly selective, corticotropin-releasing factor-1 (CRF1) receptor antagonist, R121920 ((7-(dipropylamino)-2,5-dimethyl-3- [2-(dimethylamino)-5-pyridyl] pyrazolo [1,5-a] pyrimidine), was assessed in two rat models of permanent focal cerebral ischemia, where the middle cerebral artery (MCA) was occluded either through the subtemporal approach or using the intraluminal suture technique. R121920 rapidly crossed the blood–brain barrier after intravenous (IV) bolus administration (10 mg/kg), with peak brain concentrations at 5 minutes (2.26 ± 0.40 μg/mL), which were approximately 2-fold greater than those in plasma (0.98 ± 0.24 μg/mL). Treatment with R121920 (10 mg/kg IV followed by 5 mg/kg subcutaneously at hourly intervals for 4 hours) significantly ( P < 0.001) reduced total (by 40%) and cortical (by 37%) infarct volume at 24 hours after subtemporal MCA occlusion (MCAO). In the intraluminal suture MCAO model, IV administration of R121920 (10 mg/kg) at the time of ischemia onset (and at multiple times thereafter) reduced both hemispheric infarct volume (by 34%, P < 0.001) and brain swelling (by 50%, P < 0.001) when assessed at 24 hours. In this model of focal ischemia, significant reduction ( P < 0.05) in both outcome measures was obtained when R121920 administration was delayed up to 1 hour after MCAO. These results further define the antiischemic properties of selective CRF1 antagonists in two experimental models of permanent focal cerebral ischemia.

2000 ◽  
Vol 20 (5) ◽  
pp. 812-819 ◽  
Author(s):  
Sophie Batteur-Parmentier ◽  
Isabelle Margaill ◽  
Michel Plotkine

A beneficial role of nitric oxide (NO) after cerebral ischemia has been previously attributed to its vascular effects. Recent data indicate a regulatory role for NO in initial leukocyte-endothelial interactions in the cerebral microcirculation under basal and ischemic conditions. In this study, the authors tested the hypothesis that endogenous NO production during and/or after transient focal cerebral ischemia can also be neuroprotective by limiting the process of neutrophil infiltration and its deleterious consequences. Male Sprague-Dawley rats were subjected to 2 hours occlusion of the left middle cerebral artery and the left common carotid artery. The effect of NG-nitro-L-arginine methyl ester (L-NAME) (10 mg/kg, intraperitoneally), an NO synthase inhibitor, was examined at 48 hours after ischemia on both infarct size and myeloperoxidase activity, an index of neutrophil infiltration. L-NAME given 5 minutes after the onset of ischemia increased the cortical infarct volume by 34% and increased cortical myeloperoxidase activity by 60%, whereas administration of L-NAME at 1, 7, and 22 hours of reperfusion had no effect. Such exacerbations of infarction and myeloperoxidase activity produced when L-NAME was given 5 minutes after the onset of ischemia were not observed in rats rendered neutropenic by vinblastine. These results suggest that after transient focal ischemia, early NO production exerts a neuroprotective effect by modulating neutrophil infiltration.


2009 ◽  
Vol 110 (6) ◽  
pp. 1271-1278 ◽  
Author(s):  
Jean-Laurent Codaccioni ◽  
Lionel J. Velly ◽  
Chahrazad Moubarik ◽  
Nicolas J. Bruder ◽  
Pascale S. Pisano ◽  
...  

Background Preconditioning the brain with volatile anesthetics seems to be a viable option for reducing ischemic cerebral injury. However, it is uncertain whether this preconditioning effect extends over a longer period of time. The purpose of this study was to determine if sevoflurane preconditioning offers durable neuroprotection against cerebral ischemia. Methods Rats (Sprague-Dawley) were randomly allocated to two groups: nonpreconditioned control group (n = 44) and preconditioned group (n = 45) exposed to 2.7 vol% sevoflurane (45 min) 60 min before surgery. Animals in both groups were anesthetized with 3.0 vol% sevoflurane and subjected to transient middle cerebral artery occlusion. After 60 min of awake focal ischemia, the filament was removed. Functional neurologic outcome (range 0-18; 0 = no deficit), cerebral infarct size (Nissl staining), and apoptosis (Terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick-end labeling; cleaved caspase-3 staining) were evaluated at 3, 7, and 14 days after ischemia. Results Sevoflurane preconditioning significantly improved functional outcome and reduced infarct volume (109 +/- 43 vs. 148 +/- 56 mm(3)) 3 days after ischemia compared to the control group. However, after 7- and 14-day recovery periods, no significant differences were observed between groups. The number of apoptotic cells was significantly lower in the preconditioned group than in the control group after 3- and 7-day recovery periods. Fourteen days after ischemia, no differences were observed between groups. Conclusion In this model of transient focal cerebral ischemia, sevoflurane preconditioning induced effective but transient neuroprotective effects. Sevoflurane preconditioning also decreased ischemia-induced apoptosis in a more sustained way because it was observed up to 7 days after injury.


2018 ◽  
Vol 45 (2) ◽  
pp. 537-546 ◽  
Author(s):  
Yong Wang ◽  
Qianyao Ren ◽  
Xing Zhang ◽  
Huiling Lu ◽  
Jian Chen

Background/Aims: Emerging evidence suggests that autophagy plays important roles in the pathophysiological processes of cerebral ischemia and reperfusion injury. Calycosin, an isoflavone phytoestrogen, possesses neuroprotective effects in cerebral ischemia and reperfusion in rats. Here, we investigated the neuroprotective effects of calycosin against ischemia and reperfusion injury, as well as related probable mechanisms behind autophagy pathways. Methods: A cerebral ischemic and reperfusion injury model was established by middle cerebral artery occlusion in male Sprague-Dawley rats. Neurological scores, infarct volumes, and brain water content were assessed after 24 h reperfusion following 2 h ischemia. Additionally, the expression of the autophagy-related protein p62 and NBR1 (neighbor of BRCA1 gene 1), as well as Bcl-2, and TNF-α in rat brain tissues was measured by RT-PCR, western blotting and immunohistochemical analyses. Results: The results showed that calycosin pretreatment for 14 days markedly decreased infarct volume and brain edema, and ameliorated neurological scores in rats with focal cerebral ischemia and reperfusion. It was observed that levels of p62, NBR1 and Bcl-2 were greatly decreased, and levels of TNF-α significantly increased after ischemia and reperfusion injury. However, calycosin administration dramatically upregulated the expression of p62, NBR1 and Bcl-2, and downregulated the level of TNF-α. Conclusions: All data reveal that calycosin exerts a neuroprotective effect on cerebral ischemia and reperfusion injury, and the mechanisms maybe associated with its anti-autophagic, anti-apoptotic and anti-inflammatory action.


2002 ◽  
Vol 22 (2) ◽  
pp. 161-170 ◽  
Author(s):  
Michiko Nakamura ◽  
Kazuhiko Nakakimura ◽  
Mishiya Matsumoto ◽  
Takefumi Sakabe

Two types of ischemic tolerance in the brain, rapid and delayed, have been reported in terms of the interval between the conditioning and test insults. Although many reports showed that delayed-phase neuroprotection evoked by preconditioning is evident after 1 week or longer, there have been a few investigations about rapidly induced tolerance, and the reported neuroprotective effects become ambiguous 7 days after the insults. The authors examined whether this rapid ischemic tolerance exists after 7 days of reperfusion in a rat focal ischemic model, and investigated modulating effects of the adenosine A1 receptor antagonist DPCPX (8-cyclopentyl-1,3-dipropylxanthine). Preconditioning with 30 minutes of middle cerebral artery occlusion reduced infarct volume 7 days after 180 minutes of subsequent focal ischemia given after 1-hour reperfusion. The rapid preconditioning also improved neurologic outcome. These beneficial effects were attenuated by pretreatment of 0.1 mg/kg DPCPX, which did not influence the infarct volume after conditioning (30 minutes) or test (180 minutes) ischemia when given alone. The results show that preconditioning with a brief focal ischemia induces rapid tolerance to a subsequent severe ischemic insult, the effect of which is still present after 7 days of reperfusion, and that the rapid ischemic tolerance is possibly mediated through an adenosine A1 receptor–related mechanism.


1995 ◽  
Vol 15 (4) ◽  
pp. 611-618 ◽  
Author(s):  
Shunya Takizawa ◽  
Kazushi Matsushima ◽  
Hitoshi Fujita ◽  
Kazunori Nanri ◽  
Saori Ogawa ◽  
...  

Although a number of studies have demonstrated the neuroprotective effects of antagonists of postsynaptic N-methyl-d-aspartate (NMDA) and non-NMDA receptors in cerebral ischemia, little is known about the treatment of cerebral infarction through presynaptic blocking of extracellular glutamate release. We evaluated the effects of a presynaptic selective N-type calcium channel antagonist (SNX-111, given intravenously by continuous infusion at 5 mg/kg/h from 20 min prior to occlusion until 2 h postocclusion) on blood flow, extracellular glutamate, and infarct volume in rats with permanent occlusions of the right middle cerebral and right common carotid arteries plus 1-h transient occlusion of the left common carotid artery. There was no significant difference in CBF in the occluded cortex during the experiment between the treated and vehicle groups. SNX-111 significantly reduced total amount of extracellular glutamate during the experiment and the peak value of the glutamate after occlusion from 44.2 ± 15.8 μ M (mean ± SD) to 21.4 ± 11.4 μ M (p < 0.01). Infusion of SNX-111 also significantly reduced the cortical volume of infarction from 47.2 ± 5.8 to 19.9 ± 7.3% (p < 0.0001). These results suggest that SNX-111 has a protective effect against focal ischemia through the inhibition of glutamate release from presynaptic sites, although SNX-111 may also affect the release of other neurotransmitters.


1997 ◽  
Vol 17 (11) ◽  
pp. 1137-1142 ◽  
Author(s):  
Kazushi Takahashi ◽  
Joel H. Greenberg ◽  
Paul Jackson ◽  
Keith Maclin ◽  
Jie Zhang

Poly(adenosine 5′-diphosphoribose) synthetase (PARS) has been described as an important candidate for mediation of neurotoxicity by nitric oxide. In the current study, we demonstrate for the first time that in vivo administration of a potent PARS inhibitor, 3,4-dihydro 5-[4-1(1-piperidinyl) butoxy]-1(2H)-isoquinolinone, leads to a significant reduction of infarct volume in a focal cerebral ischemia model in the rat. Focal cerebral ischemia was produced by cauterization of the right distal middle cerebral artery (MCA) with bilateral temporary common carotid artery occlusion for 90 minutes. 3,4-Dihydro 5[4-(1-piperidinyl) butoxy]-1(2H)-isoquinolinone was dissolved in dimethyl sulfoxide and injected intraperitoneally. Animals were treated 2 hours before MCA occlusion (control, n = 14; 5 mg/kg, n = 7; 10 mg/kg, n = 7; 20 mg/kg, n = 7; 40 mg/kg, n = 7), and 2 hours after MCA occlusion (same doses as before treatment). Twenty-four hours after MCA occlusion, the total infarct volume was measured using 2,3,5-triphenyltetrazolium chloride. Inhibition of PARS leads to a significant decrease in the damaged volume in the 5 mg/kg–treated group (106.7 ± 23.2 mm3; mean ± SD, P < 0.002), the 10 mg/kg–treated group (76.4 ± 16.8 mm3, P < 0.001), and the 20 mg/kg–treated group (110.2 ± 42.0 mm3, P < 0.02) compared with the control group (165.2 ± 34.0 mm3). The substantial reduction in infarct volume indicates that the activation of PARS may play an important role in the pathogenesis of brain damage in cerebral ischemia through intracellular energy depletion.


1996 ◽  
Vol 85 (1) ◽  
pp. 117-124 ◽  
Author(s):  
Marin B. Marinov ◽  
Kimberly S. Harbaugh ◽  
P. Jack Hoopes ◽  
Harold J. Pikus ◽  
Robert E. Harbaugh

✓ The known cytoprotective properties of MgSO4 led the authors to study its effects on infarct size in rats when administered intraarterially before reversible focal ischemia. Following an intracarotid infusion of MgSO4 in the amount of 30 mg/kg (24 animals), 90 mg/kg (18 animals), or an equal volume of vehicle (23 animals), middle cerebral artery occlusion was produced in rats by means of an intraluminal suture technique. Reperfusion occurred after 1.5 (42 animals) or 2 hours (23 animals) of ischemia. Automated, volumetric measurements of 2′,3′,5′-triphenyl-2H-tetrazolium chloride—stained coronal brain sections demonstrated a statistically significant decrease in infarct size for MgSO4 treatment groups compared to controls. Cytoprotection was greater in animals subjected to 1.5 hours of ischemia (28.4% reduction in infarct volume, p ≤ 0.001, Student's t-test), than in those having 2 hours of ischemia (19.3% reduction, p < 0.05). Animals given 90 mg/kg MgSO4 prior to 1.5 hours of ischemia (12 animals) showed a 59.8% reduction in infarct volume compared to controls (11 animals, p < 0.001) and a 43.1% reduction compared to the 30 mg/kg group (11 animals, p < 0.001). Analysis of variance demonstrated the statistically significant effects of MgSO4 doses on infarct volume across all groups (F = 22.95, p < 0.0001). The neuroprotective effect of intraarterial MgSO4 in this model is robust, dose dependent, and related to the duration of ischemia. The compound may be valuable for limiting infarction if given intraarterially before induction of reversible ischemia during cerebrovascular surgery.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Hui Hu ◽  
Xiao ou Sun ◽  
Fang Tian ◽  
Hao Zhang ◽  
Qing Liu ◽  
...  

Previous report has indicated that isosteviol has neuroprotective effects. However, isosteviol was administered preventively before ischemia and the inclusion criteria were limited. In the present study, a more soluble and injectable form of isosteviol sodium (STVNA) was administered intravenously hours after transient or permanent middle cerebral artery occlusion (tMCAO or pMCAO) to investigate its neuroprotective effects in rats. The rats were assessed for neurobehavioral deficits 24 hours after ischemia and sacrificed for infarct volume quantification and histology evaluation. STVNA 10 mg·kg−1can significantly reduce the infarct volumes compared with vehicle in animals subjected to tMCAO and is twice as potent as previously reported. Additionally, the therapeutic window study showed that STVNA could reduce the infarct volume compared with the vehicle group when administered 4 hours after reperfusion. A similar effect was also observed in animals treated 4 hours after pMCAO. Assessment of neurobehavioral deficits after 24 hours showed that STVNA treatment significantly reduced neurobehavioral impairments. The number of restored NeuN-labeled neurons was increased and the number of TUNEL positive cells was reduced in animals that received STVNA treatment compared with vehicle group. All of these findings suggest that STVNA might provide therapeutic benefits against cerebral ischemia-induced injury.


2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Jintanaporn Wattanathorn ◽  
Jinatta Jittiwat ◽  
Terdthai Tongun ◽  
Supaporn Muchimapura ◽  
Kornkanok Ingkaninan

Cerebral ischemia is known to produce brain damage and related behavioral deficits including memory. Recently, accumulating lines of evidence showed that dietary enrichment with nutritional antioxidants could reduce brain damage and improve cognitive function. In this study, possible protective effect ofZingiber officinale, a medicinal plant reputed for neuroprotective effect against oxidative stress-related brain damage, on brain damage and memory deficit induced by focal cerebral ischemia was elucidated. Male adult Wistar rats were administrated an alcoholic extract of ginger rhizome orally 14 days before and 21 days after the permanent occlusion of right middle cerebral artery (MCAO). Cognitive function assessment was performed at 7, 14, and 21 days after MCAO using the Morris water maze test. The brain infarct volume and density of neurons in hippocampus were also determined. Furthermore, the level of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in cerebral cortex, striatum, and hippocampus was also quantified at the end of experiment. The results showed that cognitive function and neurons density in hippocampus of rats receiving ginger rhizome extract were improved while the brain infarct volume was decreased. The cognitive enhancing effect and neuroprotective effect occurred partly via the antioxidant activity of the extract. In conclusion, our study demonstrated the beneficial effect of ginger rhizome to protect against focal cerebral ischemia.


Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Hui Hu ◽  
Qing Liu ◽  
Fang Tian ◽  
Hao Zhang ◽  
DaiXin Qu ◽  
...  

Background & Objective: Isosteviol is a molecule derived from Steviaside which has been used as sweetener worldwide. In this study, sodium salt of isosteviol (STVNA) was given i.v. in rats hours after the transient or permanent middle cerebral artery occlusion (tMCAO or pMCAO) to investigate its therapeutic neuroprotective effects. Methods: In male Sprague-Dawley rats 2 hours tMCAO with reperfusion or pMCAO was induced and ischemia were confirmed by a laser doppler flowmetry simultaneously. In dosage study, animals were divided into 6 groups: sham, vehicle, or treatment with STVNA at dosage of 1, 5, 10mg•kg-1 or Edaravone 1 hour before the onset of reperfusion. In therapeutic time window study, animals were divided into 5 groups: sham, vehicle, STVNA (10mg•kg-1) at 0, 2 or 4 hours after reperfusion. In pMCAO study, animals were divided into 5 groups: sham, vehicle or STVNA (10mg•kg-1) at 1, 2 or 4 hours after ischemia. Rats were assessed for neurobehavioral deficits after 24 hours and sacrificed for infarct volume quantitation and histology evaluation. Proteomic analysis of the penumbra area in some rats used a Snaps G2x MS-TOF system. Results: In dosage study, the infarct volume of STVNA 10mg•kg-1 group was significantly less compared either with the vehicle group (22±2% vs 41±5%, p< 0.01) or with the Edaravone group (22±2% vs 30±3%, p< 0.05 ). The therapeutic window study shows that STVNA treated at 4h after reperfusion still has significant effects than vehicle group (32±4% vs 41±5%, p<0.05). In pMCAO study, the infarct volume of STVNA at 4h still decreased comparing the vehicle group(29±5% vs 50±6%, p< 0.05).In all STVNA treated groups the neurobehavioral deficits were significantly improved, and there are more restored NeuN-labeled neurons and alleviated TUNEL positive cells in penumbra in comparing with the vehicle group. Proteomic analysis indicates that proteins involved in various inflammations associated signal pathways were dramatically increased by tMCAO, and then were greatly reduced after treated with STVNA. Conclusions: STVNA exhibited remarkable neuroprotective effects when administered 4 hours after pMCAO or 4 hours after reperfusion of tMCAO. Since STVNA has low systemic toxicity, it may be a better alternative for the treatment of stroke.


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