• Title/Summary/Keyword: amyloid ${\beta}$

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The effect of scopoletin on Aβ-induced neuroinflammatory response in microglial BV-2 cells

  • Mun, Hui-Jin;Cho, Hyun-Jeong
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.6
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    • pp.165-170
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    • 2020
  • In this paper, it was confirmed that scopoletin inhibits neuroinflammation induced by amyloid beta oligomer (Aβ1-42) in microglial BV-2. The mechanisms of inflammatory cytokines and inflammatory mediators by scopoletin were identified. Alzheimer's disease is the most common neurodegenerative disease, but it is a disease whose specific etiology is unknown, and many studies are trying to solve it. We first measured the cell viability with the CCK-8 assay method to confirm that scopoletin and Aβ1-42 are toxic to BV-2 cells. Expression levels of interleukin 1 beta (IL-1β), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and nuclear factor-κB (NF-κB) in inflammatory reactions induced by Aβ1-42 with western blot were analyzed. The ANOVA assay was used to compare protein expression differences between BV-2 cells treated with Aβ1-42 alone and BV-2 cells pretreated with Aβ1-42 and scopoletin. Therefore, this study suggested that scopoletin is worth developing as a neuroinflammatory protection agent for Alzheimer's disease in the future.

Overexpression and Refolding of BACE2 (BACE2의 대량발현 및 리폴딩)

  • Park, Sun Joo;Tai, Shuaiqi;Lee, Yeon-Ji;Jeon, You-Jin;Kim, Yong-Tae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.4
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    • pp.370-375
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    • 2014
  • BACE2 is a membrane-bound aspartic protease that is highly homologous with BACE1. While BACE1 processes the amyloid precursor protein (APP) at a key step in generating ${\beta}$-amyloid peptide and presumably causes Alzheimer's disease (AD), BACE2 has not been demonstrated to be involved in APP processing directly, and its physiological functions are unknown. To determine its function and to develop inhibitors from marine sources, we constructed an overexpression vector for producing BACE2. The gene encoding human BACE2 protease was amplified using the polymerase chain reaction and cloned into the pET11a expression vector, resulting in pET11a/BACE2. Recombinant BACE2 protease was overexpressed successfully in E. coli as inclusion bodies, refolded using the rapid-dilution method, and purified via two-step fast protein liquid chromatography using Sephacryl S-300 gel filtration and Resource-Q column chromatography. The BACE2 protease produced was an active form. This study provides an efficient method not only for studying the basic properties of BACE2, but also for developing inhibitors from natural marine sources.

The Protective Effects of Seokchangpowonji-san on $H_2O_2$-Mediated Cell Death of Neuro 2A as an Alzheimer Model System (산화적 손상에 의한 Neuro 2A 치매모델에서 석창포원지산의 방어효과)

  • Yim Jun-Mo;Lee Min-Goo;Yun Jong-Min;Lee In;Moon Byung-Soon
    • The Journal of Korean Medicine
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    • v.26 no.1 s.61
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    • pp.161-173
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    • 2005
  • Objective : The water extract of Seokchangpowonji-san (SWS) has traditionally been used for treatment of dementia in oriental medicine. However, little is known about the mechanism by which the water extract of SWS rescues cells from neurodegenerative disease such as Alzheimer's disease. Methods & Results: This study was designed to investigate the protective mechanisms of SWS on $\beta-amyloid$ or $H_2O_2$-induced$ cytotoxicity in neuro 2A cells. $H_2O_2$ markedly decreased the viability of neuro 2A cells, which was characterized by apparent apoptotic features such as membrane blebbing as well as fragmentation of genomic DNA and nuclei. However, the water extract of SWS significantly reduced $H_2O_2-induced$ cell death and apoptotic characteristics through reduction of intracellular peroxide generation. Also, the. extract prevented the mitochondrial dysfunction including the disruption of mitochondria membrane permeability transition (MPT) and the modulation in expression of Bcl-2 family proteins in $H_2O_2­treated$ neuro 2A cells. Furthermore, pretreatment with SWS inhibited the activation of caspase-3, and in turn, degradation of ICAD/DFF45 was completely abolished in $H_2O_2-treated$ cells. Conclusion: Taken together, the data suggest that the protective effects of the water extract of SWS against $\beta-amyloid$ induced oxidative injuries may be achieved through modulation of mitochondrial dysfunction.

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Identification of Gene Expression Signatures in Korean Acute Leukemia Patients

  • Lee kyung-Hun;Park Se-Won;Kim In-Ho;Yoon Sung-Soo;Park Seon-Yang;Kim Byoung-Kook
    • Genomics & Informatics
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    • v.4 no.3
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    • pp.97-102
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    • 2006
  • In acute leukemia patients, several successful methods of expression profiling have been used for various purposes, i.e., to identify new disease class, to select a therapeutic target, or to predict chemo-sensitivity and clinical outcome. In the present study, we tested the peripheral blood of 47 acute leukemia patients in an attempt to identify differentially expressed genes in AML and ALL using a Korean-made 10K oligo-nucleotide microarray. Methods: Total RNA was prepared from peripheral blood and amplified for microarray experimentation. SAM (significant analysis of microarray) and PAM (prediction analysis of microarray) were used to select significant genes. The selected genes were tested for in a test group, independently of the training group. Results: We identified 345 differentially expressed genes that differentiated AML and ALL patients (FWER<0.05). Genes were selected using the training group (n=35) and tested for in the test group (n=12). Both training group and test group discriminated AML and ALL patients accurately. Genes that showed relatively high expression in AML patients were deoxynucleotidyl transferase, pre-B lymphocyte gene 3, B-cell linker, CD9 antigen, lymphoid enhancer-binding factor 1, CD79B antigen, and early B-cell factor. Genes highly expressed in ALL patients were annexin A 1, amyloid beta (A4) precursor protein, amyloid beta (A4) precursor-like protein 2, cathepsin C, lysozyme (renal amyloidosis), myeloperoxidase, and hematopoietic prostaglandin D2 synthase. Conclusion: This study provided genome wide molecular signatures of Korean acute leukemia patients, which clearly identify AML and ALL. Given with other reported signatures, these molecular signatures provide a means of achieving a molecular diagnosis in Korean acute leukemia patents.

Study on the Effect of KamiTongJonHaaATang Extracts on Thrombosis, Brain Ischemia and Brain damage (가미통전화어탕(加味通栓化瘀湯)이 혈전증(血栓症)과 뇌허혈증(腦虛血症) 및 뇌손상(腦損傷)에 미치는 영향(影響)에 대한 실험적(實驗的) 연구(硏究))

  • Ahn, Taek Won;Kim, Byeong Tak
    • Journal of Haehwa Medicine
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    • v.8 no.1
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    • pp.379-401
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    • 1999
  • The effect of KamiTongJonHaaATang extracts on hypercholesterolemia, platelet aggregation, pulm onary thrombosis, KCN-induced coma, forcal brain ischemia, cytotoxicity of PC12 cells induced by amyloid ${\beta}$ protein(25-35), and NO production in RAW cells stimulated lipopolysaccharide were investigated, respectively. The results were summarized as follows; 1. KTJHAT extracts showed a significant decrease of serum total cholesterol, triglyceride, phospholipid, LDL-cholesterol, and VLDL-cholesterol in hypercholesterolemia induced by 2% cholesterol diet in NZW rabbit. 2. KTJHAT extracts induced a significant inhibition of human platelet aggregation induced by thrombin and ADP but did not affect human platelet aggregation induced by collagen. 3. KTJHAT extracts showed a protective effect on pulmonary thrombosis induced by collagen and epinephrine. 4. KTJHAT extracts prolonged the duration of KCN-induced coma. 5. KTJHAT extracts showed a significant decrease of brain ischemic area and edema in MCA occlusion. Also, KTJHAT extracts showed a decrease of neurologic grade in hind limb but did not affect neurologic grade in fore limb. 6. KTJHAT extracts showed a protective effect on cytotoxicity of PC 12 cells induced by amyloid ${\beta}$ protein(25-35) in a dose dependent manner. 7. KTJHAT extracts showed a significant decrease of NO production in RAW cells induced by lipopolysaccharide. These results suggested that KTJHAT extracts might be usefully applied for prevention and treatement of thrombosis and brain damage.

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β-Amyrin Ameliorates Alzheimer's Disease-Like Aberrant Synaptic Plasticity in the Mouse Hippocampus

  • Park, Hye Jin;Kwon, Huiyoung;Lee, Ji Hye;Cho, Eunbi;Lee, Young Choon;Moon, Minho;Jun, Mira;Kim, Dong Hyun;Jung, Ji Wook
    • Biomolecules & Therapeutics
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    • v.28 no.1
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    • pp.74-82
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    • 2020
  • Alzheimer's disease (AD) is a progressive and most frequently diagnosed neurodegenerative disorder. However, there is still no drug preventing the progress of this disorder. β-Amyrin, an ingredient of the surface wax of tomato fruit and dandelion coffee, is previously reported to ameliorate memory impairment induced by cholinergic dysfunction. Therefore, we tested whether β-amyrin can prevent AD-like pathology. β-Amyrin blocked amyloid β (Aβ)-induced long-term potentiation (LTP) impairment in the hippocampal slices. Moreover, β-amyrin improved Aβ-induced suppression of phosphatidylinositol-3-kinase (PI3K)/Akt signaling. LY294002, a PI3K inhibitor, blocked the effect of β-amyrin on Aβ-induced LTP impairment. In in vivo experiments, we observed that β-amyrin ameliorated object recognition memory deficit in Aβ-injected AD mice model. Moreover, neurogenesis impairments induced by Aβ was improved by β-amyrin treatment. Taken together, β-amyrin might be a good candidate of treatment or supplement for AD patients.

Improvements in Cognitive and Motor Function by a Nutrient Delivery System Containing Sialic Acid from Edible Bird's Nest (제비집 시알산 유래 영양전달체(Nutrient Delivery System)의 인지기능 및 운동기능 개선 효과)

  • Kim, Dong-Myong;Jung, Ju-Yeong;Lee, Hyung-Kon;Kwon, Yong-Seong;Baek, Jin-Hong;Han, In Suk
    • The Korean Journal of Food And Nutrition
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    • v.33 no.6
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    • pp.614-623
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    • 2020
  • The objective of this study was to produce a nutrient delivery system (NDS) using sialic acid extracted from edible bird's nest (EBN), which improves brain function in patients with Alzheimer's disease and Parkinson's disease, by affinity bead technology (ABT). The inhibitory activity of acetylcholinesterase (AChE) and pyramidal cells in the dentate gyrus of the hippocampus were analyzed to investigate the effect of a sialic acid NDS on Alzheimer's disease. Also, the effect of a sialic acid NDS on Parkinson's disease was evaluated by rota-rod test and pole test in an animal model. Among the groups treated with donepezil, EBN, and sialic acid NDS, the AChE activity was the lowest in the sialic acid NDS-treated group. The results of the hippocampus analysis of the rat model confirmed that the sialic acid NDS inhibited amyloid-beta accumulation depending upon the concentration. Also, the sialic acid NDS group showed more improvement in motor deterioration than the1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced group in both the rota-rod test and pole test. Therefore, the sialic acid NDS had an effect of protecting not only Alzheimer's disease by inhibiting AChE and amyloid-beta accumulation, but Parkinson's disease by preventing neurotoxicity induced by MPTP.

Effects of Corticosterone on Beta-Amyloid-Induced Cell Death in SH-SY5Y Cells

  • Bo Kyeong Do;Jung-Hee Jang;Gyu Hwan Park
    • Biomolecules & Therapeutics
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    • v.32 no.1
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    • pp.77-83
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    • 2024
  • Alzheimer's disease (AD) is a neurodegenerative disease characterized by neuronal cell death and memory impairment. Corticosterone (CORT) is a glucocorticoid hormone produced by the hypothalamic-pituitary-adrenal axis in response to a stressful condition. Excessive stress and high CORT levels are known to cause neurotoxicity and aggravate various diseases, whereas mild stress and low CORT levels exert beneficial actions under pathophysiological conditions. However, the effects of mild stress on AD have not been clearly elucidated yet. In this study, the effects of low (3 and 30 nM) CORT concentration on Aβ25-35-induced neurotoxicity in SH-SY5Y cells and underlying molecular mechanisms have been investigated. Cytotoxicity caused by Aβ25-35 was significantly inhibited by the low concentration of CORT treatment in the cells. Furthermore, CORT pretreatment significantly reduced Aβ25-35-mediated pro-apoptotic signals, such as increased Bim/Bcl-2 ratio and caspase-3 cleavage. Moreover, low concentration of CORT treatment inhibited the Aβ25-35-induced cyclooxygenase-2 and pro-inflammatory cytokine expressions, including tumor necrosis factor-α and interleukin-1β. Aβ25-35 resulted in intracellular accumulation of reactive oxygen species and lipid peroxidation, which were effectively reduced by the low CORT concentration. As a molecular mechanism, low CORT concentration activated the nuclear factor-erythroid 2-related factor 2, a redox-sensitive transcription factor mediating cellular defense and upregulating the expression of antioxidant enzymes, such as NAD(P)H:quinone oxidoreductase, glutamylcysteine synthetase, and manganese superoxide dismutase. These findings suggest that low CORT concentration exerts protective actions against Aβ25-35-induced neurotoxicity and might be used to treat and/or prevent AD.

Studies on the Treatment and Prevention of Dementia by Green-Tea extracts (녹차(綠茶)추출물에 의한 치매 치료 및 예방에 관한 연구)

  • Lim, Jong-Soon
    • Journal of Haehwa Medicine
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    • v.12 no.1
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    • pp.11-26
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    • 2003
  • Alzheimer's disease (AD) is characterized by amyloid deposition and associated loss of neunons in brain regions involved in learning and memory processes. Several causes of evidence support that the congnitive disturbance is closed associated with the deficit of cerebral acetylcholine neurotransmission, and the effect of carboxyl terminal 105 amino acid fragment (CT105) of the amyloid precursor protein (APP) on the gene expression of proinflammatory cytokines. We tested it on the scopolamine-induced amnesia model of the ICR mouse using the Morris water maze with repeated orally administration of 1st Green-Tea extract (200 mg/kg) and 2nd Green-Tea extract (200 mg/kg). The Green-Tea prevents impairment of learning and memory and neuronal loss in mouse models of cognitive disturbance and it demonstrated selectivity for inhibition of acetylcholinesterase (AChE). Furthermore, the repeated administration of Green-Tea, CT105-induced alzheimer's mouse model showed central cholinergic activity by ameliorates learning and memory impairment, and isolation of CD14 microglia showed significantly decreases intracellular release of the proinflammatory cytokines tumor necrosis factor-${\alpha}$, interleukin-$1{\beta}$ and reactive oxygen species (ROS). Because of its composite profile, oral therapeutic index and a prophylactic, Green-Tea is considered the better therapeutic candidate for the treatment of Alzheimer's disease.

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Characterization and β-secretase Inhibitory Activity of Water-soluble Polysaccharides Isolated from Phellinus linteus Fruiting Body (상황버섯 자실체로부터 분리된 수용성 다당류의 특성 분석 및 이의 베타 시크리타아제 활성 저해효과)

  • Jo, Hang Soo;Choi, Doo Jin;Chung, Mi Ja;Park, Jae Kweon;Park, Yong Il
    • The Korean Journal of Mycology
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    • v.40 no.4
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    • pp.229-234
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    • 2012
  • A key molecule in the pathogenesis of Alzheimer's disease (AD) is the ${\beta}$-amyloid peptide ($A{\beta}$) generated by ${\beta}$-secretase activity, an aspartic protease. This study was designed to evaluate inhibitory effect of the high-molecular weight water-soluble polysaccharides (Et-P) isolated and purified from Phellinus linteus fruiting body on ${\beta}$-secretase activity. The Et-P was purified from the hot water extract of Phellinus linteus fruiting body mainly by 75% ethanol precipitation and DEAE-Cellulose column chromatography. From the DEAE-Cellulose chromato-gram and molecular weight analysis, the Et-P was shown to be a mixture of three polysaccharides with molecular mass of 1,629, 1,294, and 21 kDa, respectively. The monosaccharide composition of Et-P was determined to be glu-cose, galactose, and mannose as major sugars, glucose being the most prominent one (48% in mole percentage). The elemental analysis and FT-IR analysis suggested that Et-P is typical polysaccharides having at least partially ${\beta}$-linkages and possible existing as complex with phenolic compounds. The laminarinase digestion and HPAEC-PAD analysis suggested that Et-P is a variant of beta-(1,3)-glucans. The Et-P showed DPPH radical scavenging activity and, especially, a significant inhibitory activity on ${\beta}$-secreatase activity (48% inhibitin at 100 ${\mu}g/mL$), suggesting that they may inhibit the formation of $A{\beta}$ which is the major causative of Alzheimer's disease. The results of this study suggest that the water soluble polysaccharides of Phellinus linteus fruiting body can be a potent material for the development of preventive or therapeutic agents for AD.