• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.41-44
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• 1995

• The Korean Journal of Physiology and Pharmacology
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• 제11권2호
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• pp.57-64
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• 2007

Ischemic preconditioning (IPC) is known to protect the heart against ischemia/reperfusion (IR)-induced injuries, and regional differences in the mitochondrial antioxidant state during IR or IPC may promote the death or survival of viable and infarcted cardiac tissues under oxidative stress. To date, however, the interplay between the mitochondrial antioxidant enzyme system and the level of reactive oxygen species (ROS) in the body has not yet been resolved. In the present study, we examined the effects of IR- and IPC-induced oxidative stresses on mitochondrial function in viable and infarcted cardiac tissues. Our results showed that the mitochondria from viable areas in the IR-induced group were swollen and fused, whereas those in the infarcted area were heavily damaged. IPC protected the mitochondria, thus reducing cardiac injury. We also found that the activity of the mitochondrial antioxidant enzyme system, which includes manganese superoxide dismutase (Mn-SOD), was enhanced in the viable areas compared to the infarcted areas in proportion with decreasing levels of ROS and mitochondrial DNA (mtDNA) damage. These changes were also present between the IPC and IR groups. Regional differences in Mn-SOD expression were shown to be related to a reduction in mtDNA damage as well as to the release of mitochondrial cytochrome c (Cyt c). To the best of our knowledge, this might be the first study to explore the regional mitochondrial changes during IPC. The present findings are expected to help elucidate the molecular mechanism involved in IPC and helpful in the development of new clinical strategies against ischemic heart disease.

• 대한한방내과학회지
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• 제21권4호
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• pp.535-542
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• 2000

The water extracts of Samul-tang(SMT) has been used for treatment of ischemic brain damage in Oriental traditional medicine. However, little is known about the mechanism by which the water extracts of SMT rescues brain cells from ischemic damages. To elucidate the protective mechanism on ischemic induced cytotoxicity, I investigate the regulation of LPS and PMA induced iNOS expression in C6 glial cells. LPS and PMA treatment for 72 h in C6 glial cells markedly induce nitric oxide(NO), but treatment of the cells with the water extracts of SMT decrease. dose dependently nitrite formation. In addition, LPS and PMA treatment for 72 h induce severe cell death and LDH release in C6 glial cells. However treatment of the cells with the water extracts of SMT dose not induce significant changes compare to control cells. Furthermore, the protective effects of the water extracts of SMT is mimicked by treatment of $N^{G}MMA$, a specific inhibitor of NOS. LPS and PMA induced iNOS activation in C6 glial cells cause chromosomal condensation and fragmentation of nuclei by caspase activation. The treatment of the cells with the water extracts of SMT may suppress apoptosis via caspase inhibition by regulation of iNOS expression. Taken together, I suggest that the protective effects of the water extracts of SMT against ischemic brain damages may be mediated by regulation of iNOS during ischemic condition.

• 한국약용작물학회지
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• 제19권1호
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• pp.31-37
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• 2011

Previous work demonstrated that an ethanol extract (HS0608) of a mixture of three medicinal plants of Curcuma longae radix, Phellinus linteus, and Scutellariae radix markedly inhibits $A{\beta}$ (25-35)-induced neurotoxicity. The present study was performed to further verify the neuroprotective effect of HS0608 on oxidative and ischemic cerebral injury using cultured rat cortical neurons and rats. Exposure of cultured cortical neurons to $100\;{\mu}M$ hydrogen peroxide ($H_2O_2$) induced neuronal apoptotic death. At $10-100{\mu}g/ml$, HS0608 inhibited neuronal death, elevation of intracellular calcium concentration ($[Ca^{2+}]_i$), and generation of reactive oxygen species (ROS) induced by $H_2O_2$ in primary cultures of rat cortical neurons. In vivo, HS0608 prevented cerebral ischemic injury induced by 2-h middle cerebral artery occlusion (MCAO) and 24-h reperfusion. The ischemic infarct and edema were significantly reduced in rats that received HS0608 (200 mg/kg). These results suggest that the anti-oxidative properties of HS0608 may be responsible for its neuroprotective effect against focal cerebral ischemic injury and that HS0608 may have a therapeutic role in neurodegenerative diseases such as stroke.

• Journal of Chest Surgery
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• 제22권6호
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• pp.901-913
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• 1989

This study was investigated under the postulation that activation of intracellular calcium- calmodulin complex during ischemia-reperfusion leads to myocardial injury. The protective effects of calcium channel blocker, diltiazem and calmodulin inhibitors, trifluoperazine, flunarizine and calmidazolium from ischemic injury in rat hearts were observed by using Langendorff apparatus when the antagonists were infused for 3 min in the beginning of ischemia. Thereby, an increase in resting tension developed during 30-min ischemia was analyzed with regard to [1] the degree of cardiac functional recovery following 60-min reperfusion, [2] changes in biochemical variables evoked during 30-min ischemia. The results obtained were as follows: l. In the ischemic group, the resting tension was increased by 4.1*0.2 g at 30-min ischemia. However, the increase in resting tension was markedly reduced not only by pretreatment with diltiazem [3.3 p M] but also with calmodulin inhibitors, trifluoperazine [3.3 p M], flunarizine [0.5 p M] and calmidazolium [0.5 p M], respectively. 2. Recovery of myocardial contractility, +dF /dt and coronary flow were much reduced when evoked by reperfusion in the ischemic group. These variables were significantly improved either by pretreatment with diltiazem or with calmodulin inhibitors. 3. The resting tension increment evoked during ischemia was significantly inversely correlated with the degree of cardiac function recovered during reperfusion. 4. Following 30-min ischemia, the production of malondialdehyde and release of lysosomal enzyme were much increased in association with a decrease in creatine kinase activity. 5. The increases in malondialdehyde production and release of free lysosomal enzyme were suppressed by pretreatment with calmodulin inhibitors as well as diltiazem. Likewise, the decrease of creatine kinase activities was prevented by these calcium antagonists. With these results, it is indicated that a increase in resting tension observed during ischemia has an inverse relationship to the cardiac function recovered following reperfusion, and further, the later may be significantly dependent on the degree of biochemical alterations occurred during ischemia such as decrease in creatine kinase activity, increased production of malondialdehyde and increased release of free lysosomal enzyme. Thus it is concluded that calmodulin plays a pivotal role in the process of ischemic injury.

• Journal of Acupuncture Research
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• 제21권4호
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• pp.207-215
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• 2004

Objective : In order to prove the effect of Hirudin Herbal-acupuncture this experimental studies were performed by using rats that had neuronal damage due to the Middle Cerebral Artery Occulsion(MCAO). Methods : Microdialysis probes were implanted into the coordinate of striatum of anesthetized rats which consist of sham-operated 8 rats, MCAO-operated 8 rats and Hirudin Herbal-acupuncture administrated 8 rats before MCAO operating. The Hirudin Herbal-acupuncture(0.5mg/kg) was administrated to rats 30 minutes before having an operation causing the MCAO. The surgical excision lead the cross resected brain to the acute ischemic state. The brain was sliced in 2mm thickness and stained with cresyl violet buffer for the measurement of cerebral infarcted area and volume. Results : Based on the result of the tissue inspection for the cerebral ischemic cell, Hirudin Herbal-acupuncture significantly protect neurocytes. Conclusion : We suggest Hirudin Herbal-acupuncture produces protective effects against the neuronal damage induced by MCAO. Therefore, Hirudin Herbal-acupuncture may prevent delayed neuronal death(DND) in selectively vulnerable focal areas of the brain effectively.

• 대한한의학회지
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• 제25권3호
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• pp.32-44
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• 2004

Objectives : This study was undertaken to prove the effect of GSHT on the glutamate receptor, free radical and brain damage in rats subjected to brain ischemia Methods : Levels of cultured cortical neuron death caused by toxic chemicals were measured by LDH release assay. Neuroprotective effects of GSHT on brain tissues were examined in vivo by ischemic model of middle cerebral artery (MCA) occlusion. Results : GSHT showed significant inhibitory effect on LDH release induced by NMDA-kinate-Fe/sup 2+/. GSHT remarkably decreased coma duration time in a nonfatal dose of KCN and showed higher survival rate in a fatal dose. GSHT remarkably decreased ischemic area and edema induced by the MCA blood flow block. GSHT showed high improvement of forelimb and hind limb test after MCA occlusion in neurological examination. GSHT showed no significant change after MCA occlusion in pathological observation of the normal group. Conclusions : These results indicate that GSHT can be used to treat the brain damage caused by brain ischemia. Further study will be needed about the functional mechanism, etc.

• Korean Journal of Acupuncture
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• 제21권3호
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• pp.89-96
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• 2004

Objectives : In order to prove the effect of Phospholipase $A_2(PLA_2)$ Herbal-acupuncture, this experimental studies were performed by using rats that had neuronal damage due to the Middle Cerebral Artery Occulsion(MCAO). Methods : Microdialysis probes were implanted into the coordinate of striatum of anesthetized rats which consist of sham-operated 8 rats, MCAO-operated 8 rats and $PLA_2$ Herbal-acupuncture administrated 8 rats before MCAO operating. The $PLA_2$ Herbal-acupuncture(0.5mg/kg) was administrated to rats 30 minutes before having an operation causing the MCAO. The surgical excision lead the cross resected brain to the acute ischemic state. The brain was sliced in 2mm thickness and stained with cresyl violet buffer for the measurement of cerebral infarcted area and volume. Results : Based on the result of the tissue inspection for the cerebral ischemic cell, $PLA_2$ Herbal-acupuncture significantly protect neurocytes. Conclusions : We suggest $PLA_2$ Herbal-acupuncture produces protective effects against the neuronal damage induced by MCAO. Therefore, $PLA_2$ Herbal-acupuncture may prevent delayed neuronal death(DND) in selectively vulnerable focal areas of the brain effectively.

• Preventive Nutrition and Food Science
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• 제15권4호
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• pp.255-261
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• 2010

Ischemic stroke, a major cause of death and disability worldwide, is caused by occlusion of cerebral arteries that, coupled with or without reperfusion, results in prolonged ischemia (hypoxia and hypoglycemia) and, ultimately, brain damage. In this study, we examined whether methanol extract of the whole plant of Cassia mimosoides var. nomame Makino that grows naturally in Korea, as well as Japan and China, and some of its fractions obtained by partitioning with organic solvents could protect human hepatocellular carcinoma cells (HepG2) under hypoxic condition by inhibiting apoptosis. We also investigated if these extracts could attenuate brain damage in a rat model of 2 hr of ischemia, generated by middle cerebral artery occlusion, and 22 hr of reperfusion. The whole extract ($100{\mu}g$/mL) maintained the cell number at more than half of that initially plated, even after 24 hr of cell culture under hypoxic condition (3% $O_2$). In the absence of the whole extract, almost all of the cells were dead by this time point. This improvement of cell viability came from a delay of apoptosis, which was confirmed by observing the timing of the formation of a DNA ladder when assessed by gel electrophoresis. Of fractions soluble in hexane, ethyl acetate (EA), butanol and water, EA extracts were selected for the animal experiments, as they improved cell viability at the lowest concentration ($10{\mu}g$/mL). The whole extract (200 mg/kg) and EA extract (10 and 20 mg/kg) significantly reduced infarct size, a measure of brain damage, by 34.7, 33.8 and 45.2.0%, respectively, when assessed by 2,3,5-triphenyl tetrazolium chloride staining. The results suggest that intake of Cassia mimosoides var. nomame Makino might be beneficial for preventing ischemic stroke through inhibition of brain cell apoptosis.

• 동의생리병리학회지
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• 제18권2호
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• pp.586-595
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• 2004

Kamidojuk-San (KDJS) is known to be effective for treating cardiovascular diseases such hypertension, and clinically applied for the treatment of cerebral palsy or stoke patients. Yet, the overall mechanisms underlying its activity at the cellular levels are not known. Using experimental animal system, we investigated whether KDJS has protective effects on cells in cardiovascular and nervous systems. KDJS was found to rescue death of cultured primary neurons induced by AMPA, NMDA and kainate as well as BSO and Fe/sup 2+/ treatments. Moreover, KDJS treatment promoted animal's recovery from coma induced by a lethal dose of KCN treatment, and improved survival in animals exposed to lethal dose of KCN. Neurological examinations further showed that KDJS reduced the time which is required for animals to respond in terms of forelimb and hindlimb movements. To examine its physiological effects on cardiovascular and nervous systems, we induced ischemic injury in hippocampal neurons and cerebral neurons by middle cerebral artery (MCA) occlusion. Histological examination revealed that KDJS significantly protected neurons from ischemic damage. Thus, the present data suggest that KDJS may play an important role in protecting cells of cardiovascular and nervous systems from external noxious stimulations.