• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.341-352
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• 2011

The purpose of this study was carried out to investigate the effect of electroacupuncture on reactive gliosis expressing GFAP in rat with transient global cerebral ischemia. Subjects were randomly divided into two groups, a control group and a electroacupuncture group on ST36, LI11 and SP9 with 2 Hz and 1 mA. The rats were sacrificed on 1, 3 and 7 days after transient cerebral ischemia using ligation of left common carotid artery. After making brain slide sections, they were immunostained with GFAP antisera(1:2,500). The results were as follows: The numbers of astrocytes of electroacupuncture group were decreased than those of control group at every 1, 2 and 7 days. Especially, the numbers of astrocytes at 3 days(p<0.01) and 8 days(p<0.05) were different statistically. And astrocytes had resting, hypertrophic and moving types on cerebral cortex. The decrease of numbers of astrocytes expressing GFAP showed that electroacupuncture could localise and minimize the brain damage by transient cerebral ischemia and cause brain cell plasticity.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.4
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• pp.167-172
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• 2006

In the present study, we developed a simple method to predict the neuronal cell death in the mouse hippocampus and striatum following transient global forebrain ischemia by evaluating both cerebral blood flow and the plasticity of the posterior communicating artery (PcomA). Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral occlusion of the common carotid artery (BCCAO) for 30 min. The regional cerebral blood flow (rCBF) was measured by laser Doppler flowmetry. The plasticity of PcomA was visualized by intravascular perfusion of India ink solution. When animals had the residual cortical microperfusion less than 15% as well as the smaller PcomA whose diameter was less than one third compared with that of basilar artery, neuronal damage in the hippocampal subfields including CA1, CA2, and CA4, and in the striatum was consistently observed. Especially, when mice met these two criteria, marked neuronal damage was observed in CA2 subfield of the hippocampus. In contrast, after transient BCCAO, neuronal damage was consistently produced in the striatum, dependent more on the degree of rCBF reduction than on the plasticity of PcomA. The present study provided simple and highly reproducible criteria to induce the neuronal cell death in the vulnerable mice brain areas including the hippocampus and striatum after transient global forebrain ischemia.

• 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.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.205.1-205.1
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• 2003

Several lines of recent evidences have shown that several pro-inflammatory genes or mediators, such as inducible nitric oxide synthase (iNOS)are strongly expressed in the ischemic brain. Inflammation is now recognized as a significant contributing mechanism in cerebral ischemia because anti-inflammatory compounds or inhibitors of iNOS have been proven to reduce ischemic brain damage. In iNOS assay, hexane fraction of M61 inhibited NO (iNOS IC50, 0.7${\mu}$g/ml). In vivo study was carried out to evaluate neuroprotective effect of hexane fraction of M61 after transient global ischemia using Mongolian gerbil ischemia model. (omitted)

• Biomolecules & Therapeutics
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• v.27 no.6
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• pp.522-529
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• 2019

M1/M2 polarization of immune cells including microglia has been well characterized. It mediates detrimental or beneficial roles in neuroinflammatory disorders including cerebral ischemia. We have previously found that sphingosine 1-phospate receptor subtype 1 ($S1P_1$) in post-ischemic brain following transient middle cerebral artery occlusion (tMCAO) can trigger microglial activation, leading to brain damage. Although the link between $S1P_1$ and microglial activation as a pathogenesis in cerebral ischemia had been clearly demonstrated, whether the pathogenic role of $S1P_1$ is associated with its regulation of M1/M2 polarization remains unclear. Thus, this study aimed to determine whether $S1P_1$ was associated with regulation of M1/M2 polarization in post-ischemic brain. Suppressing $S1P_1$ activity with its functional antagonist, AUY954 (5 mg/kg, p.o.), attenuated mRNA upregulation of M1 polarization markers in post-ischemic brain at 1 day and 3 days after tMCAO challenge. Similarly, suppressing $S1P_1$ activity with AUY954 administration inhibited M1-polarizatioin-relevant $NF-{\kappa}B$ activation in post-ischemic brain. Particularly, $NF-{\kappa}B$ activation was observed in activated microglia of post-ischemic brain and markedly attenuated by AUY954, indicating that M1 polarization through $S1P_1$ in post-ischemic brain mainly occurred in activated microglia. Suppressing $S1P_1$ activity with AUY954 also increased mRNA expression levels of M2 polarization markers in post-ischemic brain, further indicating that $S1P_1$ could also influence M2 polarization in post-ischemic brain. Finally, suppressing $S1P_1$ activity decreased phosphorylation of M1-relevant ERK1/2, p38, and JNK MAPKs, but increased phosphorylation of M2-relevant Akt, all of which were downstream pathways following $S1P_1$ activation. Overall, these results revealed $S1P_1$-regulated M1/M2 polarization toward brain damage as a pathogenesis of cerebral ischemia.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.467-475
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• 2001

Cardiac arrest, hypoxia, shock or seizure has been known to induce cerebral ischemia. This study was designed to investigate the effect of ischemia on hippocampal pyramidal layer induced by transient bilateral occlusion of the common carotid arteries. Mature Mongolian gerbils were sacrificed at days 2, 4, and 7 after carotid occlusion for 10 minutes. Sham-operated gerbils of control group were subjected to the same protocol except for carotid occlusion. During operation for ischemia, body temperature was maintained $37{\pm}0.5^{\circ}C$ in all gerbils. Paraffin-embedded brain tissue blocks were cut into coronal slices and stained with H-E stain or immunostain by TUNEL method. Neurons with the oval and prominent nucleus and without the eosinophilic cytoplasm in the subfield of hippocamapal pyramidal layer were calculated as to be viable neurons. Their chromatins were condensed or clumped. Their nuclei appeared multiangular or irregularly shrinked. The width of the pyramidal layer was reduced due to the loss of nuclei. At day 2 after reperfusion, some neurons in the CA1 subfield were slightly eosinophilic. But most neurons in the CA2 subfield were strongly eosinophilic. At day 4 day, most neurons in the CA1 subfield were severely damaged and at day 7 day, only a few survived neurons were observed. Survived neurons per longitudinal 1mm sector in the CA1, CA2, CA3, and CA4 subfields of pyramidal layer were investigated. At day 2, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfiedls were 104.5/mm (54.3%), 51.0/mm (33.8%), 105.5/mm (85.6%), and 124.3/mm (93.5%) compared to the nonischemic control group, respectively. At day 4, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfields were 3.2/mm (1.7%), 51.5/mm(34.2%), 95.3/mm (77.4%), and 112.5/mm (84.6%), respectively. At day 7, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfiedls were 0.8/mm (0.4%), 5.7/mm(3.8%), 9.8/mm (8.0%), and 5.0/mm (3.7%), respectively. The mean numbers of apoptotic positive neurons in the CA1 subfield at day 2, 4, and 7 after reperfusion were 67.8/mm, 153.2/mm and 123.7/mm, respectively. These results suggest that the transient cerebral ischemia cause severe damages in most neurons at day 7 and that the prosminent apoptotic positive neurons in hippocampal pyramidal layer are the delayed neuronal death induced by ischemia.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.2
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• pp.15-30
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• 2011

Objectives : The present study investigated the effects of Achyranthis Radix on short-term memory, apoptotic neuronal cell death in the hippocampus following transient global ischemia in gerbils. Methods : The gerbils were divided into 5 groups(n=10); Sham operation group, ischemia-induced group, ischemia-induced and 50 mg/kg Achyranthis Radix-treated group, ischemia-induced and 100 mg/kg Achyranthis Radix-treated group, ischemia-induced and 200 mg/kg Achyranthis Radix-treated group. For this study, a step-down avoidance task, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL) assay, immunohistochemistry for caspase-3 and BrdU(5-Bromo-2'-deoxyuridine), and western blotting for bax, bcl-2 were performed. Results : The results revealed that ischemic injury impaired short-term memory and increased apoototic neuronal cell death in the hippocampal CA1(cornu ammonis area 1) region. Ischemic injury enhanced cell proliferation in the hippocampal CA1 region, the compensatory and adaptive process for excessive apoptosis. Achyranthis Radix treatment improved short-term memory by suppressing ischemia-induced apoptotic neuronal cell death in the hippocampal CA1 region. Also, Achyranthis Radix suppressed the ischemia-induced increase in cell proliferation in the hippocampal CA1 region. Conclusions : We showed that Achyranthis Radix alleviates ischemia-induced apoptotic neuronal cell death, thus facilitates the recovery of short-term memory impairment induced by ischemic cerebral injury.

• 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.

• 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.

• Journal of Korean Academy of Nursing
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• v.36 no.7
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• pp.1232-1241
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• 2006

Purpose: The purpose of this study was to examine the effects of cerebral ischemia on Type I(soleus) and Type II(plantaris, gastrocnemius) muscles, and to determine the effects of isometric contraction training by electro- stimulation on Type I and II muscles in cerebral ischemia model rats. Method: Twenty-five male Sprague-Dawley rats were randomly divided into four groups: ST(stroke), STES(stroke+electrostimulation), SH(sham) and SHES (sham+electrostimulation). The ST and STES groups received a transient right middle cerebral artery occlusion operation. The SH and SHES groups received a sham operation. The STES and SHES groups had daily isometric contraction training by electrostimulation(100Hz, 45mA, 7.5V) on hindlimb muscles for 7days. Result: Plantaris and gastrocenmius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the muscle fiber cross-sectional area of gastrocnemius in the ST group significantly decreased compared with the SH group. Soleus, plantaris, gastrocnemius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the Type I muscle fiber cross-sectional area of soleus and the Type II muscle fiber cross-sectional area of gastrocnemius in the STES group significantly increased compared with the 57 group. Conclusion: Hindlimb muscle atrophy occurs after acute stroke and isometric contraction training by electrostimulation during early stages of a stroke attenuates muscle atrophy of Type I and Type II muscles.