• Journal of Korean Academy of Nursing
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• v.34 no.1
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• pp.150-159
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• 2004

Purpose: The purpose of this study was to determine the effect of DHEA on hindlimb muscles(soleus, plantaris and gastrocnemius) in a focal brain ischemia model rat. Method: Twenty-seven male Sprague-Dawley rats were randomly divided into three groups: CINS(cerebral ischemia + normal saline), CIDH(cerebral ischemia + DHEA), or SHNS(sham + normal saline). Both the CINS and CIDH groups underwent a transient right middle cerebral artery occlusion operation. In the SHNS group, a sham operation was done. 0.34mmol/kg DHEA was administered daily by an intraperitoneal injection for 7days. Results: The muscle weight, muscle fiber cross-sectional area of the Type I muscle fiber of soleus and Type II muscle fiber of plantaris and gastrocnemius, myofibrillar protein content of gastrocnemius, and muscle strength in the CINS group decreased compared with the SHNS group. The muscle weight, muscle fiber cross-sectional area of the Type II muscle fiber of plantaris and gastrocnemius, myofibrillar protein content of soleus, and muscle strength in the CIDH group increased compared with the CINS group. Conclusion: It was identified that muscle atrophy could be induced during 7 days after a cerebral infarction, and DHEA administration during the early stages of a cerebral infarction might attenuate muscle atrophy.

• Biomolecules & Therapeutics
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• v.25 no.4
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• pp.383-389
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• 2017

Dexmedetomidine is an ${\alpha}2$-adrenergic receptor agonist that exhibits a protective effect on ischemia-reperfusion injury of the heart, kidney, and other organs. In the present study, we examined the neuroprotective action and potential mechanisms of dexmedetomidine against ischemia-reperfusion induced cerebral injury. Transient focal cerebral ischemia-reperfusion injury was induced in Sprague-Dawley rats by middle cerebral artery occlusion. After the ischemic insult, animals then received intravenous dexmedetomidine of $1{\mu}g/kg$ load dose, followed by $0.05{\mu}g/kg/min$ infusion for 2 h. After 24 h of reperfusion, neurological function, brain edema, and the morphology of the hippocampal CA1 region were evaluated. The levels and mRNA expressions of interleukin-$1{\beta}$, interleukin-6 and tumor nevrosis factor-${\alpha}$ as well as the protein expression of inducible nitric oxide synthase, cyclooxygenase-2, nuclear factor-${\kappa}Bp65$, inhibitor of ${\kappa}B{\alpha}$ and phosphorylated of ${\kappa}B{\alpha}$ in hippocampus were assessed. We found that dexmedetomidine reduced focal cerebral ischemia-reperfusion injury in rats by inhibiting the expression and release of inflammatory cytokines and mediators. Inhibition of the nuclear factor-${\kappa}B$ pathway may be a mechanism underlying the neuroprotective action of dexmedetomidine against focal cerebral I/R injury.

• The Journal of Korean Medicine
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• v.30 no.2
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• pp.1-16
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• 2009

Objectives: This study investigated the effect of Yukmijihwangtang on cerebral ischemia-induced learning and memory impairment by middle cerebral artery (MCA) occlusion in rats. Methods: The ability of learning and memory of rats was measured using the eight-arm radial maze and the passive avoidance test, and profile of cholinergic neuron was assessed in the medial septum and hippocampus region by immuno-histochemistry. Results: 1. No differences were found between groups in the number of correct choices in acquisition performance during the eight-arm radial maze task. 2. No differences were found between groups on day 1 in the error rate in acquisition performance, which is defined as the number of enters into the same arm more than once within five minutes. After 5 to 6 days of test, the number of errors was significantly reduced in the Yukmijihwangtang group (forebrain ischemia group with Yukmijihwangtang treatment), compared with the ischemia group. 3. The memory processes significantly improved in the Yukmijihwangtang group according to results of the passive avoidance test. 4. The appearance of AchE (acetylcholinesterase) in the CA1 region of hippocampus significantly decreased in the ischemia group, compared with the sham group (untreated group). The appearance of AchE in the same region significantly increased in the Yukmijihwangtang group, compared with the ischemia group. 5. The appearance of ChAT (choline acetyltransferase) in the CA1 region of the hippocampus and medial septum decreased in the ischemia group, compared with the sham group. The appearance of ChAT in the same region significantly increased in the Yukmijihwangtang group, compared with the ischemia group Conclusions: This study provides evidence that Yukmijihwangtang is effective for reviving the ability of learning and memory and damaged neurons in rats with experimental cerebral ischemia.

• Journal of Korean Neurosurgical Society
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• v.50 no.3
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• pp.173-178
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• 2011

Objective : The rat middle cerebral artery thread-occlusion model has been widely used to investigate the pathophysiological mechanisms of stroke and to develop therapeutic treatment. This study was conducted to analyze energy metabolism, apoptotic signal pathways, and genetic changes in the hippocampus of the ischemic rat brain. Methods : Focal transient cerebral ischemia was induced by obstructing the middle cerebral artery for two hours. After 24 hours, the induction of ischemia was confirmed by the measurement of infarct size using 2,3,5-triphenyltetrazolium chloride staining. A cDNA microarray assay was performed after isolating the hippocampus, and was used to examine changes in genetic expression patterns. Results : According to the cDNA microarray analysis, a total of 1,882 and 2,237 genes showed more than a 2-fold increase and more than a 2-fold decrease, respectively. When the genes were classified according to signal pathways, genes related with oxidative phosphorylation were found most frequently. There are several apoptotic genes that are known to be expressed during ischemic brain damage, including Akt2 and Tnfrsf1a. In this study, the expression of these genes was observed to increase by more than 2-fold. As energy metabolism related genes grew, ischemic brain damage was affected, and the expression of important genes related to apoptosis was increased/decreased.Conclusion : Our analysis revealed a significant change in the expression of energy metabolism related genes (Atp6v0d1, Atp5g2, etc.) in the hippocampus of the ischemic rat brain. Based on this data, we feel these genes have the potential to be target genes used for the development of therapeutic agents for ischemic stroke.

• The Korea Journal of Herbology
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• v.21 no.2
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• pp.151-158
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• 2006

Objectives : The purpose of the present study is to observe the neuroprotective effect of the $NeuBo153^{\circledR}$ on transient focal cerebral ischemia in rats. Methods : $NeuBo153^{\circledR}$ was made by mixing the herbs, mainly the root of Panax ginseng, the root of Rehmannia glutinosa and Poria cocos, the stem bark of Acanthopanax senticosus, the root of Scutellaria baicalensis and Mel, and heating for 96 hours. Transient Focal cerebral ischemia (2 h of ischemia, 22 h of reperfusion) was induced by intraluminal suture method with SD rats. Sensory motor function was tested by rotarod test, prehensile traction test, beam balance test and foot fault test at 24 h after ischemia. The brain slices were stained by 2% 2, 3, 5-triphenyltetrazolium chloride and the infarct volume was measured by graphic analyzer at 24 h after ischemia. Results : $NeuBo153^{\circledR}$ treated group did not show significant differences compared with vehicle treated group in body temperature. Oral administration of $NeuBo153^{\circledR}$ reduced brain infarct volume by 29.7% compared with vehicle treated group. $NeuBo153^{\circledR}$ also showed protective effects on sensory motor functional deficits. Conclusion : $NeuBo153^{\circledR}$ treatment reduced brain damage and improved functional deficits induced by MCAo. It showed neuroprotective effects even when treatment was relayed 2 h after injury. Further research is required to evaluating long term functional recovery am accurate therapeutic range and mechanisms.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.225-233
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• 2008

Objectives : The purpose of the present study was to development of neuroprotective antioxidant agents. For the purpose, we investigated the neuroprotective effect of anti oxidant herb, the root of Polygonum cuspidatum on transient focal cerebral ischemia in rats. Methods : The roots of Polygonum cuspidatum were extracted by 85% MeOH (PCE). Radical scavenging effects were investigated using DPPH assay and TBARs (Thiobarbituric acid reaction substance) assay in brian homogenates. Neuroprotective effect was investigated using transient focal cerebral ischemia rat model (2 h of ischemia, 22 h of reperfusion) by behavioral test and measurement of brain damage using 2, 3, 5-triphenyltetrazolium chloride staining. Results : PCE showed potent and dose dependent radical scavenging effects in DPPH and TBARs assay. Oral administration of PCE reduced brain infarct volume by 29.7% and improved the sensory motor functional deficit by 29% compared with vehicle treated group. Conclusions : PCE showed radical scavenging effects and neuroprotective effect on stroke rat model. Therefore, Polygonum cuspidatum could be a candidate for the development of neuroprotective-antioxidant agents.

• Journal of Korean Neurosurgical Society
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• v.29 no.10
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• pp.1289-1295
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• 2000

Purpose : Recent evidence suggests a possible role for leukocytes in brain injury following ischemia and reperfusion. This study examined the temporal profile of ischemic tissue damage and leukocyte response after transient middle cerebral artery occlusion(MCAO) with reperfusion in the mouse. Methods : Focal cerebral ischemia was made by temporary occluding of the stem of the proximal MCA. Two groups of the mouse were investigated : (1) sham operation(n＝10), and (2)those having the arterial occlusion released after 90 minute(n＝20). By 4 hours(n＝10) and 24 hours(n＝10) after the onset of ischemia-reperfusion, fluorescein videoimages were under-taken in the pial venules of the mouse using a closed cranial window technique. Rhodamine 6G was administered as a $80-100{\mu}l/min$ i.v. loading dose and a $30-40{\mu}l/min$ i.v. maintenance dose in saline to selectively label circulating leukocytes. Neuropathologic evaluation for brain injury was accomplished using the histochemical stain 2,3,5-triphen-yltetrazolium chloride(TTC) and hematoxylin and eosin(H & E) stain. Results : The mean number of adherent leukocytes to cerebral venules in the 90 minutes MCAO and 24 hours reperfusion group were $306{\pm}24$ compared with $72{\pm}8$ in the sham operation group. In the TTC staining method, the cortical infarct affecting 34.8% of hemispheric volume were created in all of animals (n＝10) undergoing 90 minute MCAO with 24 hours reperfusion, but the infarcted area were not found in the other(sham operation and 90 minute MCAO with 4 hours reperfusion)groups. In the H & E stain, the brain tissue following 90 minute MCAO with 4 hours reperfusion revealed only a pyknosis of the nuclei with shrunken cytoplasm, but infiltrated leukocytes were not observed. After 24 hours of reperfusion, a many leukocytes were infiltrated within parenchyma and blood vessles. Conclusions : These findings demonstrate the feasiblity of continous in vivo monitoring of leukocyte adherence in cerebral venules and suggest that reperfusion induced leukocyte adherence to venular endothelium may contribute to tissue injury following focal cerebral ischemia.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.335-338
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• 2003

It is thought that highly reactive oxygen species generated after strokes plays a key role in damaging the brain. We examined free radical scavenging activity and neuroprotective effects of several medicinal herbs in a rat model of transient ischemia. Free radical scavenging property of medicinal herbs was examined in vitro using 1,1-diphenyl-2-picrylhydrazyl stable free radical. Transient ischemia was induced by intraluminal occlusion of the right middle cerebral artery for 120 min, followed by reperfusion for 22 hr in rats. Aqueous extracts of 8 medicinal herbs (200 mg/kg) were orally administered twice to transient ischemic rat prior to reperfusion and 2 hr after reperfusion. Total infarction volume in the hemisphere ipsilateral to the ischemia-reperfusion was significantly decreased in 7 groups treated with Sophora flavescens, Lycopus lucidus, Sanguisorba officinalis, Caesalpinia sappan, Albizia julibrissin, Rubia akane, Psoralea corylifolia, or Prunella vulgaris. However, neuroprotective effects of these medicinal herbs were not correlated with their antioxidative activities. These results suggest that these medicinal herbs exert neuroprotection via antioxidative as well as unknown mechanism.

• Journal of Acupuncture Research
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• v.27 no.4
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• pp.29-38
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• 2010

Objectives : The purpose of the study is to determine the neuroprotective effect of modified Boyanghwano-tang(mBHT), a traditional Korean medicine, on the transient focal cerebral ischemia in rats. Methods : Focal ischemia and reperfusion were induced by middle cerebral artery occlusion(MCAO) for 90 min, followed by 144 h reperfusion in rats. mBHT(200mg/kg body weight, p.o.) was administrated in rats once a day during reperfusion. At the end of treatment, brain infarction was measured by TTC staining, and histological change was observed by H&E staining. The expressions of Bax, Bcl-2 and cytochrome c in ischemic brains were determined by immunofluorescent analysis. Results : mBHT significantly reduced the cerebral infarct volumes of the MCAO rats. mBHT also attenuated the neuronal cell death and the expressions of pro-apoptotic molecules, bax and cytochrome c in ischemic brains. Further, mBHT significantly increased the survival time of ischemeic rats and the expression of anti-apoptotic molecule, Bcl-2 in ischemic brains. Conclusions : Our results suggest that mBHT is neuroprotective and may prove to be useful adjunct in the treatment of ischemic stroke.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.64-64
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• 2003

It is thought that highly reactive oxygen radicals generated at the ischemia-reperfusion in case of strokes play an important role in damaging the brain. We examined the neuroprotective effects from the several medicinal herbs in the transient ischemic rat model and compared their effects with the free radical scavenging activities. Transient ischemia was induced by intraluminal occusion of the right middle cerebral artety for 120 min and reperfusion was continued for 22 h in rats. The free radical scavenging properties of medicinal herbs were examined in vitro by determination of the interaction with the 1,l-diphenyl-2-picrylhydrazyl (DPPH) stable free radical. Aqueous extracts of 11 medicinal herbs (200 mg/kg) were orally administered, promptly prior to reperfusion and 2 h after reperfusion. Total infarction volume in the ipsilateral hemisphere of ischemia reperfusion rats was significantly lowered by the treatment of 7 medicinal herbs (Sophora flavescens, Lycopus lucidus, Sanguisorba officinalis, Caesalpinia sappan, Albizia julibrissin, Rubia akane, Psoralea corylifolia, Prunella vulgaris). However, all of these medicinal herbs did not show antioxidative activities. These results suggest that neuroprotective effects of several drugs are not always correlated with their antioxidative properties.