• 대한한의학회지
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• 제29권2호
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• pp.151-164
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• 2008

Objective: To investigate the effects of Yeongdamsagantang (YDGT) on apoptosis of neuronal cells that can result in dementia. Method: The water extract of the YDGT was tested in vitro for its beneficial effects on neuronal survival and neuroprotective functions, particularly in connection with $A{\beta}$ oligomer-related dementias. $A{\beta}$ oligomers derived from proteolytic processing of the ${\beta}-amyloid$ precursor protein (APP), including the $amyloid-{\beta}$ peptide $(A{\beta})$, play a critical role in the pathogenesis of Alzheimer's disease. A neuroblastoma cell line stably expressing an $A{\beta}$ oligomerassociated neuronal degeneration was used to investigate if YDGT inhibits formation of $A{\beta}$ oligomer. To measure the ATP generating level in mitochondrial membrane, luciferin/luciferase luminescence kit (Promega) and luminator was used, and to survey the protein's apparition, confocal microscopy was used. Result: $A{\beta}oligomer$ had a profound attenuation in the increase in CT105 expressing neuro2A cells from YDGT. Experimental evidence indicates that YDGT protected against neuronal damage from cells, but its cellular and molecular mechanisms remain unknown. We demonstrated that YDGT inhibited formation of $amyloid-{\beta}$ $(A{\beta})$ oligomers, which were the behavior, and possibly causative, features of AD. The decreased $A{\beta}$ oligomer in the presence of YDGT was observed in the conditioned medium of this $A{\beta}oligomer-secreting$ cell line under in vitro. In the cells, YDGT significantly attenuated mitochondrion-initiated apoptosis. Conclusion: (i) a direct $A{\beta}$ oligomer toxicity and the apoptosis initiated by the mitochondria; and (ii) multiple cellular and molecular neuroprotective mechanisms, including attenuation of apoptosis and direct inhibition of $A{\beta}$ oligomer aggregation, underlie the neuroprotective effects of YDGT.

• 대한한의학회지
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• 제26권3호
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• pp.27-42
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• 2005

Objectives : Alzheimer's disease (AD) is a progressive and fatal neurodegenerative disease characterized by amyloid plaques and neurofibrillary tangles. These plaques are associated with degenerating neuronal processes and consist primarily of fibrillary aggregates of beta-amyloid$ protein, generated from amyloid precursor protein (APP). Another amyloidogenic fragment, the carboxyl terminus (CT) of APP, which is composed of 99-105 amino acid residues containing the complete $A{\beta}$ sequence, also appears to be toxic to neurones. Recent evidence suggest that CT105, carboxy terminal 105 amino acids peptide fragment of APP, may be an important factor causing neurotoxicity in AD. Methods : Although a variety of oriental prescriptions including Pinelliae rhizoma have traditionally been utilized for the treatment of AD, their pharmacological effects and action mechanisms have not yet been fully elucidated. In the present study, we investigated effects of the dichloromethane extract of Pinelliae rhizoma (PINR) on neurotoxicity and the formation of reactive oxygen species (ROS) and nitric oxide (NO) in SK-N-SH cells overexpressed with CT105. In addition, we evaluated its radical scavenging activity and effects on acetylcholinesterase (AChE) activity. Furthermore, effects on cognitive deficits induced by scopolamine treatment in rats were evaluated. Results ; We found in this study that PINR significantly inhibited apoptotic neuronal death induced by CT105 overexpression in SK-N-SH cells. Based on morphological examinations by phase-contrast microscopy, PINR reversed apoptotic changes of CT105-expressed cells. It was also found that PINR significantly promoted neurite outgrowth and inhibited formation of ROS nd NO. PINR was shown to scavenge DPPH radicals and noncompetitively inhibit AChE activity. Furthermore, it reduced scopolamine-induced memory impairment in rata, assessed by passive avoidance test. Conclusions : Taken together, these results demonstrate that PINR exhibits neuroprotective, antioxidant, and memory enhancing effects, and therefore may bs beneficial for the treatment of AD.

• 생약학회지
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• 제47권3호
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• pp.251-257
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• 2016

In this study, the radical scavenging activity and protective effect of ethanol extract from leaf of Engelhardtia chrysolepis HANCE (ECE) against oxidative stress were investigated under in vitro and cellular system. ECE showed strong radical scavenging activities in 1,1-diphenyl-2-picrylhydrazyl, hydroxyl(${\cdot}OH$) and nitric oxide(NO) radical as a concentration-dependent manner. Particularly, strong scavenging activity against the ${\cdot}OH$ and NO radical were observed with the $IC_{50}$ value of $1.30{\mu}g/ml$ and $12.61{\mu}g/ml$, respectively. Furthermore, the cellular oxidative stress was induced by amyloid beta($A{\beta}_{25-35}$) in C6 glial cells. The treatment of $A{\beta}_{25-35}$ to C6 glial cells generated high levels of reactive oxygen species(ROS) and declined cell viability. However, production of ROS was decreased by the treatment of ECE. In addition, the cell viability was significantly increased at each concentration(10, 25, $50{\mu}g/ml$) as dose-dependent manner. The Alzheimer's disease-related protein expressions in $A{\beta}_{25-35}$-treated C6 glial cells were analyzed. The ECE treatment inhibited expression of amyloid precursor protein(APP), C-terminal fragment-${\beta}(CTF-{\beta})$, ${\beta}$-site APP cleaving enzyme(BACE), phosphorylated tau(p-tau) proteins in C6 glial cells induced by $A{\beta}_{25-35}$. The present study indicated that ECE has strong radical scavenging activity and neuroprotective effect through attenuating oxidative stress.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2011년도 추계학술발표회
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• pp.31-45
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• 2011

The amyloid ${\beta}$-peptide ($A{\beta}$), which originates from the proteolytic cleavage of amyloid precursor protein (APP), plays a central role in the pathogenesis of Alzheimer's disease (AD). Mounting evidence indicates that different species of $A{\beta}$, such as $A{\beta}$ oligomers and fibrils, may contribute to AD pathogenesis via distinct mechanisms at different stages of the disease. Importantly, elevation and accumulation of soluble $A{\beta}$ oligomers closely correlate with cognitive decline and/or disease progression in animal models of AD. In agreement with these studies, oligomers of $A{\beta}$ have been shown to directly affect synaptic plasticity, a neuronal process that is known to be essential for memory formation. Our previous studies showed that $A{\beta}$ induces the breakdown of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a phospholipid that regulates key aspects of neuronal function. PI(4,5)P2 breakdown was found to be a key step toward synaptic and memory dysfunction in a mouse model of AD. To this end, we seek to identify small molecules that could elevate the levels of PI(4,5)P2 and subsequently block $A{\beta}$ oligomer-induced breakdown of PI(4,5)P2 and synaptic dysfunction.. We found that (20S)Rg3, an active triterpene glycoside from heat-processed ginseng, serves as an agonist for phosphatidylinositol 4-kinase IIalpha (PI4KIIalpha), which is a lipid kinase that mediates a rate-limiting step in PI(4,5)P2 synthesis. Consequently, (20S)Rg3 stimulates PI(4,5)P2 synthesis by directly stimulating the activity of PI4KIIalpha. Interestingly, treatment of a mouse model of AD with (20S)Rg3 leads to reversal of memory deficits. Our data suggest that the PI(4,5)P2-promoting effects of (20S)Rg3 may help mitigate the cognitive symptoms associated with AD.

• 약학회지
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• 제49권2호
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• pp.168-173
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• 2005

Alzheimers disease (AD) is the most prevalent form of neurodegenerations associated with aging in the human population. This disease is characterized by the extracellular deposition of beta-amyloid (A ${\beta}$) peptide in cerebral plaques. The A ${\beta}$ peptide is derived from the ${\beta}$-amyloid precursor protein ( ${\beta}$APP). Photolytic processing of ${\beta}$APP by ${\beta}$-secretase(beta-site APP-cleaving enzyme, BASE) and ${\gamma}$-secretase generates the A ${\beta}$ peptide. Several lines of evidence support that A ${\beta}$-induced neuronal cell death is major mechanisms of development of AD. Accordingly, the ${\beta}$-and ${\gamma}$-secretase have been implicated to be excellent targets for the treatment of AD. We previously found that sesaminol glucosides have improving effect on memory functions through anti-oxidative mechanism. In this study, to elucidate possible other mechanism (inhibition of ${\beta}$-and ${\gamma}$-secretase) of sesaminol glucosides, we examined the improving effect of sesaminol glucosides in the scopolamine (1 mg/kg/mouse)-induced memory dysfunction using water maze test in the mice. Sesaminol glucosides (3.75, 7.5 mg/kg/6ml/day p.o., for 3 weeks) reversed the latency time, distance and velocity by scopolamine in dose dependent manner. Next, ${\beta}$-and ${\gamma}$-secretase activities were determined in different regions of brain. Sesaminol glucosides dose-dependently attenuated scopolamine-induced ${\beta}$-secretase activities in cortex and hippocampous and ${\gamma}$-secretase in cortex. This study therefore suggests that sesaminol glucosides may be a useful agent for prevention of the development or progression of AD, and its inhibitory effect on secretase may play a role in the improving action of sesaminol glucosides on memory function.

• 대한약침학회지
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• 제27권2호
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• pp.70-81
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• 2024

Objectives: Cognitive impairments, ranging from mild to severe, adversely affect daily functioning, quality of life, and work capacity. Despite significant efforts in the past decade, more than 200 promising drug candidates have failed in clinical trials. Herbal remedies are gaining interest as potential treatments for dementia due to their long history and safety, making them valuable for drug development. This review aimed to examine the mechanisms behind the effect of Polygonum multiflorum on cognitive function. Methods: This study focused primarily on the effects of Polygonum multiflorum and its chemical constituents on cognitive behavioral outcomes including the Morris water maze, the passive avoidance test, and the Y maze, as well as pathogenic targets of cognitive impairment and Alzheimer's disease (AD) like amyloid deposition, amyloid precursor protein, tau hyperphosphorylation, and cognitive decline. Additionally, a thorough evaluation of the mechanisms behind Polygonum multiflorum's impact on cognitive function was conducted. We reviewed the most recent data from preclinical research done on experimental models, particularly looking at Polygonum multiflorum's effects on cognitive decline and AD. Results: According to recent research, Poligonum multiflorum and its bioactive components, stilbene, and emodin, influence cognitive behavioral results and regulate the pathological target of cognitive impairment and AD. Their mechanisms of action include reducing oxidative and mitochondrial damage, regulating neuroinflammation, halting apoptosis, and promoting increased neurogenesis and synaptogenesis. Conclusion: This review serves as a comprehensive compilation of current experiments on AD and other cognitive impairment models related to the therapeutic effects of Polygonum multiflorum. We believe that these findings can serve as a basis for future clinical trials and have potential applications in the treatment of human neurological disorders.

• 동의신경정신과학회지
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• 제15권2호
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• pp.103-118
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• 2004

Objective : This experiment was designed to investigate the effect of KongJin-dan(KJD) on the Alzheimer's disease. Method : The effects of KJD on $LI-1{\beta}$, IL-6, $TNF-{\alpha}$, amyloid precursor proteins(APP), acetylcholinesterase(AChE), glial fibrillary acidic protein(GFAP) mRNA of PC-12 and THP-1 cell treated by CT105 and AChE activity, APP production of PC-12 cell lysate treated by CT105 were investigated, respectively. Results : 1. KJD suppressed $LI-1{\beta}$, IL-6, $TNF-{\alpha}$, APP, AChE, GFAP mRNA in THP-1 and PC-12 cell treated by CT105. 2. KJD suppressed AChE activity and production of APP significantly in cell lysate of PC-12 cell treated by CT105. Conclusions : This study shows that KJD might be usefully applied for prevention and treatment of Alzheimer's disease.

• Bulletin of the Korean Chemical Society
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• 제26권8호
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• pp.1225-1228
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• 2005

C-terminal fragments of APP (APP-CTs), that contain A$\beta$ sequence, are found in neurotic plaques, neurofibrillary tangles and the cytosol of lymphoblastoid cells obtained from AD patients. CT26, Thr639-Asp664 (TVIVITLVMLKKKQYTSIHH GVVEVD) includes not only the transmembrane domain but also the cytoplasmic domain of APP. This sequence is produced from cleavage of APP by caspase and $\gamma$-secretase. In this study, the solution structure of CT26 was investigated using NMR spectroscopy and circular dichroism (CD) spectropolarimeter in various membrane-mimicking environments. According to CD spectra and the tertiary structure of CT26 determined in TFE-containing aqueous solution, CT26 has an α-helical structure from $Val^{2}\;to\;Lys^{11}$ in TFE-containing aqueous solution. However, according to CD data, CT26 adopts a $\beta$-sheet structure in the SDS micelles and DPC micelles. This result implies that CT26 may have a conformational transition between $\alpha$-helix and $\beta$-sheet structure. This study may provide an insight into the conformational basis of the pathological activity of the C-terminal fragments of APP in the model membrane.

• 생명과학회지
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• 제17권1호
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• pp.18-23
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• 2007

신경세포에 특이적으로 발현되는 단백질인 Fe65는 두 개의 phosphotyrosine binding(PTB) 도메인을 가지고 있다. 두번째 PTB(PTB2)도메인은 아밀로이드 베타 전구 단백질(APP)의 세포질 도메인 조각(AICD)와 결합한다. 최근 연구 결과들은 AICD와 Fe65로 이루어진 결합체가 알츠하이머병에서 신경세포를 죽게 하는 유전자를 발현한다고 제시하고 있다. 따라서 Fe65와 AICD의 결합을 방해하는 화합물은 알츠하이머병을 치료하는데 후보물질이 될 수 있다. 하지만 AICD와 Fe65와 관련된 신호전달에 대한 분자적 기전은 잘 알려져 있지 않다. 이번 연구에서는 Fe65의 PTB2도메인을 baculovirus시스템에서 과발현시킨 결과를 보고한다. 세균 및 척추동물 세포를 이용한 시스템과 비교했을 때, baculovirus 시스템 이 훨씬 효과적 이 다는 것을 발견했다. 정제된 재조합 단백질을 이용하여 초기 결정을 얻었다. 결정을 이용하여 앞으로 밝힐 3차원 구조는 Fe65관련 신호전달체계에 대한 분자 기전 및 이에 대한 저해제 개발에 큰 도움을 줄 것이다.

• 동의생리병리학회지
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• 제23권2호
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• pp.397-404
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• 2009

For standardization of LMK02 quality, Ginsenoside Rg3 of Red Ginseng and Decursin of Angelica gigas Nakai in the constituents of LMK02 were estimated as indicative components. From LMK02 water extract, has been used in vitro test for its beneficial effects on neuronal survival and neuroprotective functions, particularly in connection with APP-related dementias and Alzheimer's disease (AD). $A{\beta}$ oligomer derived from proteolytic processing of the ${\beta}$-amyloid precursor protein (APP), including the amyloid-${\beta}$ peptide ($A{\beta}$), play a critical role in the pathogenesis of Alzheimer's dementia. We determined that oligomer amyloid-${\beta}$ ($A{\beta}$) have a profound attenuation in the increase in rat hippocampus H19-7 cells from. Experimental evidence indicates that LMK02 protects against neuronal damage from cells, but its cellular and molecular mechanisms remain unknown. Using a hippocampus cell line on $A{\beta}$ oligomer-induced neuronal cytotoxicity, we demonstrated that LMK02 inhibits formation of $A{\beta}$ oligomer, which are the behavior, and possibly causative, feature of AD. In the Red Ginseng, the average amounts of Ginsenoside Rg3 were $47.04{\mu}g/g$ and $42.3{\mu}g/g$, 90 % of its weight were set as a standard value. And, in the Angelica gigas Nakai, the average amounts of Decursin were 2.71 mg/g and 2.44mg/g, 90 % of its weight were also set as a standard value. The attenuated $A{\beta}$ oligomer in the presence of LMK02 was observed in the conditioned medium of this $A{\beta}$ oligomer-induced cells under in vitro. In the cells, LMK02 significantly activated antiapoptosis and decreased the production of ROS. These results suggest that neuronal damage in AD might be due to two factors: a direct $A{\beta}$ oligomer toxicity and multiple cellular and molecular neuroprotective mechanisms, including attenuation of apoptosis and direct inhibition of $A{\beta}$ oligomer, underlie the neuroprotective effects of LMK02 treatment.