• 제목/요약/키워드: ${\beta}$-amyloid protein ($A{\beta}$)

검색결과 199건 처리시간 0.03초

대조환(大造丸) 추출물이 ${\beta}$-amyloid로 유도된 Alzheimer's disease 병태(病態)모델에 미치는 영향 (The Effects of Daejo-hwan(DJR) on the Alzheimer's Disease Model Induced by ${\beta}$-amyloid.)

  • 이지인;정대규
    • 동의신경정신과학회지
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    • 제18권3호
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    • pp.55-82
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    • 2007
  • Ohjective: This research investigates the effect of the DJR on Alzheimer's disease. Method: 1.The effects of the DJR extract on IL.-$1{\beta}$, IL-6, TNF-${\alpha}$, cox-2, and NOS-II mRNA of BV2 microglia cell line treated with LPS; 2. the behavior: 3. the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with ${\beta}$A were investigated. Result: 1. The DJR extract suppressed the expression of IL-$1{\beta}$, IL-6 and TNF-${\alpha}$ mRNA in BV2 microglia cell line treated with LPS. 2. The DJR extract suppressed the expression of IL-$1{\beta}$, IL-6, and TNF-${\alpha}$ protein production in BV2 microglia cell line treated with LPS. 3. For the DJR extract group a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by .${\beta}$A in the Moms water maze experiment, which measured stop-through latency, and distance movement-through latency. 4. The DJR extract suppressed the over-expression of IL-$1{\beta}$ protein, TNF-${\alpha}$ protein and CD68/CD11b, in the mice with Alzheimer's disease induced by ${\beta}$A 5. The DJR extract reduced the infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by ${\beta}$A. 6. The DJR extract reduced the tau protein, GFAP protein, and presenilin1/2 protein (immunohistochemistry) of hippocampus in the mice with Alzheimer's disease induced by ${\beta}$A. Conclusion: These results suggest that the DJR extract may he effective for the prevention and treatment of Alzheimer's disease. Investigation into the clinical use of the DJR extract for Alzheimer's disease of suggested for future research.

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β-Secretase (BACE1) Purification by Refolding Method and Complex with Hispidin

  • Lim, Ji-Hong;Lee, Bo Ram;Park, Hee Won;Hong, Bum Soo;Lim, Beong Ou;Kim, Young Jun
    • 대한화학회지
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    • 제58권6호
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    • pp.553-559
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    • 2014
  • Alzheimer's disease (AD) is a devastating neurodegenerative disease that represents the most common form of dementia among the elderly population. The deposition of aggregated ${\beta}$-amyloid ($A{\beta}$) senile plaques in the human brain is a classic observation in the neuropathology of AD, yet an understanding of the mechanism of their formation remains elusive. $A{\beta}$ is formed through endoproteolysis of the amyloid precursor protein (APP) by ${\beta}$-secretase (BACE1, ${\beta}$-site APP-cleaving enzyme) and ${\gamma}$-secretase. In this study, BACE1 protein was successfully over-expressed, purified, and refolded and utilized in a binding study with hispidin. We developed a simpler refolding method using a urea gradient and size-exclusion gel filtration to purify an active BACE1 protein variant, in larger quantities than that reported previously, and measured the binding affinity of hispidin to the BACE1 protein variant through isothermal titration calorimetry.

베타-아밀로이드 단백질 유전자 발현 연구 (Gene Expression of Beta-Amyloid Precursor Protein)

  • 김종석;우종인;서유헌;김주한;이부영
    • 생물정신의학
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    • 제3권2호
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    • pp.170-180
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    • 1996
  • Lowered immune function in the senile dementia patients may be related to the abnormal metabolism of amyloid precursor protein(APP). To investigate the passibility of an abnormal metabolism of APP in lymphocytes and the possible role of APP in the activation of lymphocytes in senile dementia patients, immunohistochemical study of rat spleen and fluorescence activated cell sorter analysis(FACS) of human lymphocytes with the specific antigen far each lymphocyte and double fluorescent marker with antibody to APP were performed. After stimulating lymphocyte with phytohemagglutinin(PHA), APP mRNA and protein were extracted and quantitfied and the influence of ${\beta}$-amyloid protein($A{\beta}$) specific antibody on lymphocyte division was investigated. In spleen, the majority of cells showing $A{\beta}$ immunoreactivity was found in the T-sell dependent zone. FACS indicated that around 90% $CD_4(+)$ T-cells and 60% of $CD_8(+)$ T-sell were immunoreactive to $A{\beta}$ specific antibody(mAb 4G8). Northern blot analysis shows that lymphocyte APP mRNA was gradually increased to reach a maximum at 3 days after activation with lectin mitogen PHA. However, the $A{\beta}$ immunoreactivity an cell surface remained constant during stimulation with PHA, indicating that the release of APP(secreted farm of APP) might be increased. A very large increase in soluble APP secretion was observed in T-lymphocyte upon activation, but only law levels in the resting stale. Immunoblot was carried out an the protein obtained from cell lysate after stimulating lymphocyte by applying PHA to the cultured lymphocyte, and the result was that $A{\beta}$ band of immature farm under 116 KDa marker decreased as the duration of culture was increased after PHA stimulation. The monoclonal $A{\beta}$ specific(4G8) and polyclonal APP antibodies did not inhibit the [$^3H$]-thymidine uptake of mitogen-treated lymphocytes significantly, suggesting that mitogenesis can not be inhibited by specific $A{\beta}$ and polyclonal APP antibody. These results suggest that APP is expressed in T-cell and might be closely associated with the function of T-cells.

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Interaction Models of Substrate Peptides and β-Secretase Studied by NMR Spectroscopy and Molecular Dynamics Simulation

  • Lee, Jee-Young;Lee, Sung-Ah;Kim, Jin-Kyoung;Chae, Chi-Bom;Kim, Yangmee
    • Molecules and Cells
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    • 제27권6호
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    • pp.651-656
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    • 2009
  • The formation of ${\beta}$-amyloid peptide ($A{\beta}$) is initiated from cleavage of amyloid precursor protein (APP) by a family of protease, ${\alpha}$-, ${\beta}$-, and ${\gamma}$-secretase. Sub W, a substrate peptide, consists of 10 amino acids, which are adjacent to the ${\beta}$-cleavage site of wild-type APP, and Sub M is Swedish mutant with double mutations on the left side of the ${\beta}$-cleavage site of APP. Sub W is a normal product of the metabolism of APP in the secretary pathway. Sub M is known to increase the efficiency of ${\beta}$-secretase activity, resulting in a more specific binding model compared to Sub W. Three-dimensional structures of Sub W and Sub M were studied by CD and NMR spectroscopy in water solution. On the basis of these structures, interaction models of ${\beta}$-secretase and substrate peptides were determined by molecular dynamics simulation. Four hydrogen bonds and one water-mediated interaction were formed in the docking models. In particular, the hydrogen bonding network of Sub M-BACE formed spread over the broad region of the active site of ${\beta}$-secretase (P5-P3'), and the side chain of P2- Asn formed a hydrogen bond specifically with the side chain of Arg235. These are more favorable to the cleavage of Sub M by ${\beta}$-secretase than Sub W. The two substrate peptides showed different tendency to bind to ${\beta}$-secretase and this information may useful for drug development to treat and prevent Alzheimer's disease.

들깨 메탄올 추출물의 acetylcholinesterase 억제활성 및 세포독성 보호효과 (Acetylcholinesterase Inhibitory Activity and Protective Effect against Cytotoxicity of Perilla Seed Methanol Extract)

  • 최원희;엄민영;안지윤;김성란;강명화;하태열
    • 한국식품과학회지
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    • 제36권6호
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    • pp.1026-1031
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    • 2004
  • 들깨 메탄올 추출물이 acetylcholinesterase(AChE)의 활성 및 PC 12 cell 세포사멸에 미치는 영향을 검토하였다. AChE에 대한 억제환성은 들깨 메탄을 추출물의 농도가 높을수록 유의적으로 높았으며 추출물의 분획물 중에서는 n-butanol층이 가장 높은 억제율을 나타내었다. L-glutamate 또는 ${\beta}-amyloid$ protein $(A{\beta})$으로 유도된 PC 12 cell에 대한 세포사멸 억제효과도 추출물의 농도가 높을수록 유의적으로 증가하였다. 또한 rat brain에 $FeSO_{4^-}H_2O_2$로 산화적 스트레스를 유발시켜 추출물의 TBARS 생성 억제활성을 조사한 결과 들깨 메탄을 추출물은 농도가 높아질수록 산화적 스트레스에 대한 억제활성이 증가하였으며 분획물 중에서는 n-butanol층에서 가장 높은 억제활성을 나타내었다. 이상의 결과들로 미루어 볼 때 들깨 메탄을 추출물은 AChE 활성을 억제하고 glutamate 또는 $A{\beta}$에 의하여 유도된 PC12 cell의 세포사멸을 억제하며 이러한 효과는 들깨 메탄을 추출물의 항산화력에 기인할 수도 있을 것으로 사료되었다.

Purification and characterization of β-secretase inhibitory peptide from sea hare (Aplysia kurodai) by enzymatic hydrolysis

  • Lee, Jung Kwon;Kim, Sung Rae;Byun, Hee-Guk
    • Fisheries and Aquatic Sciences
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    • 제21권5호
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    • pp.13.1-13.8
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    • 2018
  • Amyloid plaque, also called senile plaque, the product of aggregation of ${\beta}$-amyloid peptides ($A{\beta}$), is observed in brains of the patients with Alzheimer's disease (AD) and is one of the key factors in etiology of the disease. In this study, hydrolysates obtained from the sea hare (Aplysia kurodai) were investigated for ${\beta}$-secretase inhibitory peptide. The sea hare's muscle protein was hydrolyzed using six enzymes in a batch reactor. Trypsin hydrolysate had highest ${\beta}$-secretase inhibitory activity compared to the other hydrolysates. ${\beta}$-secretase inhibitory peptide was separated using Sephadex G-25 column chromatography and high-performance liquid chromatography on a C18 column. ${\beta}$-secretase inhibitory peptide was identified as eight amino acid residues of Val-Ala-Ala-Leu-Met-Leu-Phe-Asn by N-terminal amino acid sequence analysis. $IC_{50}$ value of purified ${\beta}$-secretase inhibitory peptide was $74.25{\mu}M$, and Lineweaver-Burk plots suggested that the peptide purified from sea hare muscle protein acts as a competitive inhibitor against ${\beta}$-secretase. Results of this study suggest that peptides derived from sea hare muscle may be beneficial as anti-dementia compounds in functional foods or as pharmaceuticals.

아밀로이드 베타로 유도된 신경세포 사멸에 대한 PineXol®의 보호효과 (Protective Effect of PineXol® against Amyloid-β-induced Cell Death)

  • 한경훈;이승희;박광성;송관영;김정희;박은국;한성희
    • 한국식품영양학회지
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    • 제30권6호
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    • pp.1279-1285
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    • 2017
  • $Amyloid-{\beta}$ protein ($A{\beta}$) is known to increase free radical production in neuronal cells, leading to cell death by oxidative stress. The purpose of this study was to evaluate the protective effects of $PineXol^{(R)}$ on $A{\beta}_{25-35}$ induced neuronal cell death. Rat pheochromocytoma (PC-12) cells were pre-treated with $100{\mu}g/mL$ of $PineXol^{(R)}$ for 2 h. The cells were exposed to single dose of $30{\mu}M$ $A{\beta}_{25-35}$ for 24 h. Cell death was assessed by a cell count kit-8 (CCK-8) assay, lactate and dehydrogenase (LDH) release assay. An Apoptotic process was analyzed by a protein expression of the Bcl-2 family using western blotting. Cell viability increased in PC-12 cells treated with both $A{\beta}_{25-35}$ and $PineXol^{(R)}$, compared to the control group. $PineXol^{(R)}$ induced a decrease of the Bcl-2 protein expression (p<0.05), while Bax and Sod1 increased (p<0.05), indicating attenuation of $A{\beta}_{25-35}$ induced apoptosis. These results suggest that $PineXol^{(R)}$ may be a good candidate for the prevention of Alzheimer's disease(AD).

Alzheimer's Disease and Apoptosis

  • Kim, Young-Hoon;Kim, Hye-Sun;Park, Cheol-Hyoung;Jeong, Sung-Jin;Kim, Young-Kyung;Kim, Sun-Hee;Lee, Sang-Kyeng;Suh, Yoo-Hun;Kim, Sung Su
    • 생물정신의학
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    • 제5권1호
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    • pp.66-70
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    • 1998
  • Apoptosis is a form of cell death in which the cells shrink and exhibit nuclear chromatin condensation and DNA fragmentation, and yet maintain membrane integrity. Many lines of evidence have shown that brain neurons are vulnerable to degeneration by apoptosis. Also it has been suggested that apoptosis is one of the mechanism contributing neuronal loss in Alzheimer's disease(AD), since the conditions in the disease($A{\beta}$ peptide, oxidative stress, low energy metabolism) are the inducers that activate apoptosis. Indeed some neurons in vulnerable regions of the AD brain show DNA damage, chromatin condensation, and apoptic bodies. Consistently, mutations in AD causative genes(Amyloid precursor protein, Presenilin-1 and Presenilin- 2) increase $A{\beta}$ $peptide_{1-42}(A{\beta}_{1-42})$ and sensitize neuronal cell to apoposis. However, several lines of evidence have shown that the location of neuronal loss and $A{\beta}$ peptide deposition is not correlated in AD brain and transgenic mice brain over-expressing $A{\beta}_{1-42}$. Taken together, these data may indicated that $A{\beta}$ peptide(and other causative factors of AD) can interact with other cellular insults or risk factors to exacerbate pathological mechansim of AD through apoptosis. Thus, this review discusses possible role and mechanism of apoptosis in AD.

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Development of Inhibitors of $\beta$-Amyloid Plaque Formation

  • Kim, Dong-Jin
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2006년도 Spring Conference
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    • pp.123-135
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    • 2006
  • Alzheimer's disease (AD) is the most common form of dementia in the aging population and is clinically characterized by a progressive loss of cognitive abilities. Pathologically, it is defined by the appearance of senile plaques - extracellular insoluble, congophilic protein aggregates composed of amyloid $\beta$ (A$\beta$) and neurofibrillary tangles (NFTs) - inyracellular lesions consisting of paired helical filaments from hyperphosphorylated cytoskeletal tau protein as described by Alois Alzheimer a century ago. These hallmarks still serve as the major criteria for a definite diagnosis of the disease. Consequently, one of the key strategy for drug development in this disease area focuses on reducing the concentration of cerebral A$\beta$ plaque by using substances that inhibit A$\beta$ fibril formation. We focused on developing inhibitors by synthesizing several kinds of aromatic molecules. The synthetic compounds were initially screened to evaluate the effective compound by tioflavin T fluorescence assay. The selected effective compounds were tested cytotoxicity and protective effect from A$\beta$-induced neuronal toxicity by cell based MTT assay with HT22 hippocampal neurons. The BBB permeability on effectors was also tested in in vitro co-culture model(HUVEC/C6 cell line). The behavior test wea carried out in mutant APP/PS1 transgenic mouse model of Alzheimer's disease. And inhibition of A$\beta$ fibril formation by the effective compound was monitored with transmitted electron microscopic images.

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