• Clinical and Experimental Pediatrics
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• 제48권4호
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• pp.425-432
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• 2005

목 적 : 폴리글루타민 질환은 해당 발현단백질의 연속되는 글루타민 아미노산 서열이 신장되기 때문에 일어나는 질환군이다. 현 연구는 폴리글루타민 질환 형질전환 초파리 모델들이 환자들 에서와 유사한 장애를 나타내는지 확인하기 위해 수행되었다. 방 법 : 폴리글루타민 질환 (SCA3) 형질전환 초파리를 대상으로 벽을 기어오르는 운동 능력을 검사하였다. 또한 유전학적인 방법을 통해서 아폽토시스를 억제하는 bcl-2 유전자와 화학적 샤페론이 뇌신경의 퇴행에 어떤 영향을 미치는지 확인하였으며 향후의 연구를 위해 척수소뇌 운동실조증 타입 2 (SCA2) 질환을 발현하는 형질전환 초파리를 생산하였다. 결 과 : SCA3 형질전환 초파리에서 신장된 폴리글루타민 배열을 지니는 질환성 초파리의 경우 신경계에서 해당 단백질을 발현하였을 경우 전형적인 운동 능력 상실을 나타냈다. 아폽토시스를 억제하는 유전자인 bcl-2를 함께 발현했을 경우, 신장된 단백질의 유독한 영향을 약화시키지 못했지만, 화학적 샤페론인글리세롤의 경우 적어도 눈에서의 유독한 영향은 억제하는 것으로 보인다. 본 연구진에 의해 개발된 SCA2 형질전환 초파리의 경우 유해 단백질의 발현 정도가 낮아서 정확한 분석이 어려웠다. 결 론 : SCA3 형질전환 초파리는 환자들에서 발견되는 운동실조증을 보였다. 글리세롤과 같은 화학적 샤페론이 현재 치료가 전무한 이 종류의 질환군의 치료에 효과적일 것으로 사료된다.

• 생명과학회지
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• 제19권4호
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• pp.520-525
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• 2009

영아형 바텐병은 PPT1 결핍 및 기능장애로 인해 발병하며, 12,500명 당 1명의 발병률을 가진 신경 퇴행 질환이다. 전 세계적으로 수많은 연구가 진행 중 이지만, 아직 명확하게 밝혀진 발병원인 및 치료방법에 대해서는 알려지고 있지 않다. 본 연구에서는 뇌에서 풍부하게 발현되는 neurogranin의 발현수준이 WT과 EBD KO 쥐에서 어떤 변화를 보이는지 확인하기 위해 mRNA, 단백질, 배양된 neurospheres를 이용하여 실험을 수행하였다. real-time PCR을 통한 neurogranin의 발현수준 비교 결과 WT에서는 노화와 무관하게neurogranin mRNA 수준에 차이가 없었으나, EBD KO 쥐에서는 노화가 진행됨에 따라 neurogranin mRNA 발현수준이 감소하였으며, 뇌에서 추출된 단백질을 이용한 western blot 분석에서도 real-time PCR과 동일한 결과를 확인할 수 있었다. 또한 WT, EBD KO 쥐의 태아로 부터 neural stem cell 인 neurospheres를 배양하여 western blot 분석을 수행한 결과 PPT1 결핍에 의해 neurogranin의 정상적인 인산화에 문제가 발생함을 확인하였다. 이러한 결과들을 바탕으로 neurospheres에 산화스트레스 유발물질인 $H_2O_2$를 처리하였고, 24시간 경과 후 항산화제인 NAC을 처리하자 $H_2O_2$를 처리한 시료에서는 mock control인 인산화된 neurogranin에 비해 그 수준이 증가하였으며, $H_2O_2$ 처리 후 NAC을 투여한 시료의 인산화 수준은 mock control 보다는 높았지만 $H_2O_2$만을 처리한 시료 수준보다 neurogranin의 인산화 정도가 감소하는 결과를 확인하였다. 이러한 결과들을 통해 PPT1 결핍으로 인해 신경세포 내에 과다하게 인산화된 neurogranin이 존재하며, neurogranin 인산화 정도는 세포가 지닌 산화스트레스 정도에 의해 변화함을 알 수 있었다. 또한 항산화제를 사용하여 세포의 산화스트레스 수준을 감소시킬 경우 neurogranin의 기능을 정상적으로 회복시킬 수 있는 가능성을 확인하였다.

• 동의생리병리학회지
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• 제16권5호
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• pp.976-988
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• 2002

The aim of this study was to examine the memory and attention enhancement effect of YMG-1 and YMG-2, which are modified herbal extracts from Yukmijihwang-tang (YMJ). YMJ, composing six herbal medicine, has been used for restoring the normal functions of the body to consolidate the constitution, nourishing and invigorating the kidney functions for hundreds years in Asian countries. A series of studies reported that YMJ and its components enhance memory retention, protects neuronal cell from reactive oxygen attack and boost immune activities. Recently the microarray analysis suggested that YMG-1 protects neurodegeneration through modulating various neuron specific genes. A total of 55 subjects were divided into three groups according to the treatment of YMG-1 (n=20), YMG-2 (n=20) and control (C; n=15) groups. Before treatments, all of subjects were subjected to the assessments on neuropsychological tests of K-WAIS test, Rey-Kim memory test, and psychophysiological test of Event-Related Potential (ERP) during auditory oddball task and repeated word recognition task. They were repeatedly assessed with the same methods after drug treatment for 6 weeks. Although no significant effect of drug was found in Rey-Kim memory test, a significant interaction (P = .010, P < 0.05) between YMG-2 and C groups was identified in the scores digit span and block design, which are the subscales of K-WAIS. The very similar but marginal interaction (P = .064) between YMG-1 and C groups was found too. In ERP analysis, only YMG-1 group showed decreasing tendency of P300 latency during oddball task while the others tended to increase, and it caused significant interaction between session and group (p= .004). This result implies the enhancement of cognitive function in due to consideration of relationship between P300 latency and the speed of information processing. However, no evidence which could demonstrate the significant drug effect was found in neither amplitude or latency. These results come together suggest that YMG-1, 2 may enhance the attention, resulting in enhancement of memory processing. For elucidating detailed mechanism of YMG on learning and memory, the further studies are necessary.

• 동의생리병리학회지
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• 제16권5호
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• pp.1025-1034
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• 2002

The herbal extract (YMT_02) is a modified herbal extracts from Yukmijihwang-tang (YMJ) to promote memory-enhancing. The YMJ extracts has been widely used as an anti-aging herbal medicine for hundred years in Asian countries. The purpose of this study is to; 1) quantitatively evaluate the memory-enhancing effect of YMT_02 by behavior task, 2) identify candidate genes responsible for enhancing memory by cDNA microarray and 3) assess the anti-oxidant effect of YMT_02 on PC12 cell. Memory retention abilities are addressed by passive avoidance task with Sprague-Dawley (SD) male rat. Before the training session, the rats are subdivided into four groups and administrated with YMT_02, Ginkgo biloba, Soya lecithin and normal saline for 10 days. The retention test was performed. 24 hours after the training session. The retention time of the YMT_02 group was significantly (p<0.05) delayed (～100%), whereas Ginkgo biloba and Soya lecithin treatment delayed 20% and 10% respectively. The hippocampi of YMT_02 and control group were dissected and mANA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied to Incyte rat GEMTM 2 cDNA microarray. The microarray results show that prealbumin(transthyretin), phosphotidylethanolamine N-methyltransferase, and PEP-19 are expressed abundantly in the YMT_02 treated group. Especially, PEP-19 is a neuron-specific protein, which inhibits apoptotic processes in neuronal cell. On the other hand, transcripts of RAB15, glutamate receptor subunit 2 and CDK108 are abundant in control group. Besides, neuronal genes involved in neuronal death or neurodegeneration such as neuronal-pentraxin and spectrin are abundantly expressed in control group. Additionally, the YMT_02 shows an anti oxidative effect in the PC12 cell. The list of differentially expressed genes may implicate further insight on the action and mechanism behind the memory-enhancing effect of herbal extracts YMT_02, for example, anti-apoptotic, anti-oxidative, and neuroprotective effects.

• 동아시아식생활학회지
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• 제14권1호
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• pp.64-69
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• 2004

본 연구에서는 이미 항산화 효과로 알려져 있는 대두와 약성이 탁월한 약콩에서 AChE 활성 억제효과와 Free radical scavenger 효과를 노화로 인한 질병 예방효과에 대한 기초자료를 제공하고자 수행하였다. 1. 대두 열탕 추출물의 경우 저농도인 1, 0.1 mg/$m\ell$에서는AChE의 활성 억제 효과가 메탄을 추출물보다 높았다. (P<0.001) 2. 대두, 약콩 메탄올 추출물에서는 고농도인 5 mg/$m\ell$에서 각 시료의 효과가 62.0$\pm$2.43%, 65.0$\pm$3.29%로 비슷했으나 저농도인 0.1 mg/$m\ell$에서는 약콩의 경우 25.5$\pm$0.94%로 약콩이 대두에 비해 유의적인 AChE 억제효과를 나타냈다. (p<0.001) 3. 시간에 따른 Free radical scavenger효과는 비타민 C의 경우 시간에 따라 비슷한 효과를 보였으나 대두와 약콩은 incubating 시간에 따라 free radical 억제효과가 증가해 높은 항산화 효과를 볼 수 있었다. 4. 대두, 약콩 메탄올 추출물에서는 약콩이 고농도인 5mg/$m\ell$에서 약4배 정도의 효과를 보였으며 Free radical scavenger의 50%효과를 나타내는 $IC_{50}$/에서는 약 10배 정도로 높은 Free radical scavenger 효과를 나타내 약콩이 대두에 비해 유의적으로 높은 효과를 나타내었다. 결론적으로, 대두와 약콩의 추출물은 AChE 활성억제효과에 있어서 좋은 효과를 나타내며 또한 노화의 원인과 질병의 원인이 되는 free radical을 억제하는 효과를 가지고 있어 노인성 치매를 비롯하여 파킨슨씨병, 뇌허혈 및 뇌졸중과 같은 각종 노인성 질환예방에 도움이 될 것으로 보인다.

• The Korean Journal of Physiology and Pharmacology
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• 제21권4호
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• pp.361-370
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• 2017

Previous reports have suggested that physical and psychological stresses may trigger fibromyalgia (FM). Stress is an important risk factor in the development of depression and memory impairments. Antidepressants have been used to prevent stress-induced abnormal pain sensation. Among various antidepressants, tianeptine has been reported to be able to prevent neurodegeneration due to chronic stress and reverse decreases in hippocampal volume. To assess the possible effect of tianeptine on FM symptoms, we constructed a FM animal model induced by restraint stress with intermittent cold stress. All mice underwent nociceptive assays using electronic von Frey anesthesiometer and Hargreaves equipment. To assess the relationship between tianeptine and expression levels of brain-derived neurotrophic factor (BDNF), cAMP response element-binding protein (CREB), and phosphorylated cAMP response element-binding protein (p-CREB), western blotting and immunohistochemistry analyses were performed. In behavioral analysis, nociception tests showed that pain threshold was significantly decreased in the FM group compared to that in the control group. Western blot and immunohistochemical analyses of medial prefrontal cortex (mPFC) and hippocampus showed downregulation of BDNF and p-CREB proteins in the FM group compared to the control group. However, tianeptine recovered these changes in behavioral tests and protein level. Therefore, this FM animal model might be useful for investigating mechanisms linking BDNF-CREB pathway and pain. Our results suggest that tianeptine might potentially have therapeutic efficacy for FM.

• The Korean Journal of Physiology and Pharmacology
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• 제9권4호
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• pp.239-246
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• 2005

In the central nervous system, nitric oxide (NO) is associated with many pathological diseases such as brain ischemia, neurodegeneration and inflammation. The epigallocatechin gallate (EGCG), a major compound of green tea, is recognized as protective substance against neuronal diseases. This study is aimed to investigate the effect of EGCG on NO-induced cell death in PC12 cells. Administration of sodium nitroprusside (SNP), a NO donor, decreased cell viability in a dose- and time-dependent manner and induced genomic DNA fragmentation with cell shrinkage and chromatin condensation. EGCG diminished the decrement of cell viability and the formation of apoptotic morphologenic changes as well as DNA fragmentation by SNP. EGCG played as an antioxidant that attenuated the production of reactive oxygen species (ROS) by SNP. The cells treated with SNP showed downregulation of Bcl-2, but upregulation of Bax. EGCG ameliorated the altered expression of Bcl-2 and Bax by SNP. The release of cytochrome c from mitochondria into cytosol and expression of voltage -dependent anion channel (VDAC)1, a cytochrome c releasing channel in mitochondria, were increased in SNP-treated cells, whereas were attenuated by EGCG. The enhancement of caspase-9, preceding mitochondria-dependent pathway, caspase-8 and death receptor-dependent pathway, as well as caspase-3 activities were suppressed by EGCG. SNP upragulated Fas and Fas-L, which are death receptor assembly, whereas EGCG ameliorated the expression of Fas enhanced by SNP. These results demonstrated that EGCG has a protective effect against SNP-induced apoptosis in PC12 cells, through scavenging ROS and regulating the mitocondria- and death receptor-mediated signal pathway. The present study suggest that EGCG might be a natural neuroprotective substance.

• 생물정신의학
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• 제4권1호
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• pp.60-66
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• 1997

서울대학교병원 신경정신과에 입원하여 뇌자기공명영상촬영을 시행한 32명(남자 18명, 여자 12명)의 양극성장애환자를 대상으로 피질하 $T_2$ 강조-고신호광도의 임상적 변수에 관한 연구를 시행하여 다음과 같은 결과를 얻었다. 1) 32명의 환자중 피질하 고신호광도를 보인 환자의 수는 7명(21.8%)이었고, 8명의 40세 이상의 환자중에서는 5명(62%)이 고신호광도를 보였다. 2) 피질하 고신호광도를 보인 환자군이 그렇지 않은 군에 비해 통계적으로 유의한 수준으로 연령이 높았고(p<0.01), 연령과 정량화된 피질하 고신호광도 점수와의 상관분석에서도 유의한 양의 상관관계를 보였다(r=0.51, p<0.01). 3) 피질하 고신호광도를 보인 환자군에서 정신병적 증상의 빈도는 증가되고(p=0.06), 정동장애 가족력의 빈도는 감소한 경향을 보였다(p=0.01). 이상의 결과는 발병연령이 늦은 양극성장애 환자의 상당수에서 발견되는 피질하 고신호광도가, 유전적요인에 주로 영향을 받는 조기 발병군과는 다른 경과나 임상양상 등을 보이는 만발성 양극성장애 환자의 원인적 요소일 수 있다는 가설을 뒷받침해주는 소견이다.

• Biomolecules & Therapeutics
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• 제15권1호
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• pp.16-26
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• 2007

Tissue plasminogen activator (tPA) is a serine protease catalyzing the proteolytic conversion of plasminogen into plasmin, which is involved in thrombolysis. During last two decades, the role of tPA in brain physiology and pathology has been extensively investigated. tPA is expressed in brain regions such as cortex, hippocampus, amygdala and cerebellum, and major neural cell types such as neuron, astrocyte, microglia and endothelial cells express tPA in basal status. After strong neural stimulation such as seizure, tPA behaves as an immediate early gene increasing the expression level within an hour. Neural activity and/or postsynaptic stimulation increased the release of tPA from axonal terminal and presumably from dendritic compartment. Neuronal tPA regulates plastic changes in neuronal function and structure mediating key neurologic processes such as visual cortex plasticity, seizure spreading, cerebellar motor learning, long term potentiation and addictive or withdrawal behavior after morphine discontinuance. In addition to these physiological roles, tPA mediates excitotoxicity leading to the neurodegeneration in several pathological conditions including ischemic stroke. Increasing amount of evidence also suggest the role of tPA in neurodegenerative diseases such as Alzheimer's disease and multiple sclerosis even though beneficial effects was also reported in case of Alzheimer's disease based on the observation of tPA-induced degradation of $A{\beta}$ aggregates. Target proteins of tPA action include extracellular matrix protein laminin, proteoglycans and NMDA receptor. In addition, several receptors (or binding partners) for tPA has been reported such as low-density lipoprotein receptor-related protein (LRP) and annexin II, even though intracellular signaling mechanism underlying tPA action is not clear yet. Interestingly, the action of tPA comprises both proteolytic and non-proteolytic mechanism. In case of microglial activation, tPA showed non-proteolytic cytokine-like function. The search for exact target proteins and receptor molecules for tPA along with the identification of the mechanism regulating tPA expression and release in the nervous system will enable us to better understand several key neurological processes like teaming and memory as well as to obtain therapeutic tools against neurodegenerative diseases.

• Nutrition Research and Practice
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• 제14권5호
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• pp.438-452
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• 2020

BACKGROUND/OBJECTIVES: Brain senescence causes cognitive impairment and neurodegeneration. It has also been demonstrated that curcumin (Cur) and hesperetin (Hes), both antioxidant polyphenolic compounds, mediate anti-aging and neuroprotective effects. Therefore, the objective of this study was to investigate whether Cur, Hes, and/or their combination exert anti-aging effects in D-galactose (Dg)-induced aged neuronal cells and rats. MATERIALS/METHODS: SH-SY5Y cells differentiated in response to retinoic acid were treated with Cur (1 μM), Hes (1 μM), or a combination of both, followed by 300 mM Dg. Neuronal loss was subsequently evaluated by measuring average neurite length and analyzing expression of β-tubulin III, phosphorylated extracellular signal-regulated kinases, and neurofilament heavy polypeptide. Cellular senescence and related proteins, p16 and p21, were also investigated, including their regulation of antioxidant enzymes. In vivo, brain aging was induced by injecting 250 mg/kg body weight (b.w.) Dg. The effects of supplementing this model with 50 mg/kg b.w. Cur, 50 mg/kg b.w. Hes, or a combination of both for 3 months were subsequently evaluated. Brain aging was examined with a step-through passive avoidance test and apoptosis markers were analyzed in brain cortex tissues. RESULTS: Cur, Hes, and their combination improved neuron length and cellular senescence by decreasing the number of β-gal stained cells, down-regulated expression of p16 and p21, and up-regulated expression of antioxidant enzymes, including superoxide dismutase 1, glutathione peroxidase 1, and catalase. Administration of Cur, Hes, or their combination also tended to ameliorate cognitive impairment and suppress apoptosis in the cerebral cortex by down-regulating Bax and poly (ADP-ribose) polymerase expression and increasing Bcl-2 expression. CONCLUSIONS: Cur and Hes appear to attenuate Dg-induced brain aging via regulation of antioxidant enzymes and apoptosis. These results suggest that Cur and Hes may mediate neuroprotective effects in the aging process, and further study of these antioxidant polyphenolic compounds is warranted.