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

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Neuroprotective and Antioxidant Effects of the Butanol Fraction Prepared from Opuntia ficus-indica var. saboten

  • Cho, Jung-Sook;Han, Chang-Kyun;Lee, Yong-Sup;Jin, Chang-Bae
    • Biomolecules & Therapeutics
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    • v.15 no.4
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    • pp.205-211
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    • 2007
  • The fruits and stems of Opuntia ficus-indica var. saboten have been reported to exhibit a variety of pharmacological actions, including antioxidant, analgesic, anti-inflammatory, and anti-ulcer effects. In the present study, we evaluated effects of the butanol fraction (SK OFB901) prepared from the 50% ethanol extract of the stems on various types of neuronal injuries induced by oxidative stress, excitotoxins, and amyloid ${\beta}\;(A_{\beta})$ in primary cultured rat cortical cells. Its antioxidant and radical scavenging activities were also evaluated by cell-free bioassays. We found that SK OFB901 strongly inhibited the oxidative neuronal damage induced by $H_2O_2$ or xanthine/xanthine oxidase. In addition, it exhibited marked inhibition of the excitotoxic neuronal damage induced by glutamate, N-methyl-D-aspartic acid, or kainate. Furthermore, the $A_{\beta(25-35)}$-induced neurotoxicity was also significantly attenuated by SK OFB901. It was found to inhibit lipid peroxidation initiated by $Fe^{2+}$ and L-ascorbic acid in rat brain homogenates and scavenge 1,1-diphenyl-2-picrylhydrazyl free radicals. These results indicate that the butanol fraction prepared from the stems of Opuntia ficus-indica var. saboten exerts potent antioxidant and neuroprotective effects through multiple mechanisms, implying its potential applications for the prevention or management of neurodegenerative disorders associated with oxidative stress, excitotoxicity, and $A{\beta}$.

Cordycepin protects against β-amyloid and ibotenic acid-induced hippocampal CA1 pyramidal neuronal hyperactivity

  • Yao, Li-Hua;Wang, Jinxiu;Liu, Chao;Wei, Shanshan;Li, Guoyin;Wang, Songhua;Meng, Wei;Liu, Zhi-Bin;Huang, Li-Ping
    • The Korean Journal of Physiology and Pharmacology
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    • v.23 no.6
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    • pp.483-491
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    • 2019
  • Cordycepin exerts neuroprotective effects against excitotoxic neuronal death. However, its direct electrophysiological evidence in Alzheimer's disease (AD) remains unclear. This study aimed to explore the electrophysiological mechanisms underlying the protective effect of cordycepin against the excitotoxic neuronal insult in AD using whole-cell patch clamp techniques. ${\beta}$-Amyloid ($A{\beta}$) and ibotenic acid (IBO)-induced injury model in cultured hippocampal neurons was used for the purpose. The results revealed that cordycepin significantly delayed $A{\beta}$ + IBO-induced excessive neuronal membrane depolarization. It increased the onset time/latency, extended the duration, and reduced the slope in both slow and rapid depolarization. Additionally, cordycepin reversed the neuronal hyperactivity in $A{\beta}$ + IBO-induced evoked action potential (AP) firing, including increase in repetitive firing frequency, shortening of evoked AP latency, decrease in the amplitude of fast afterhyperpolarization, and increase in membrane depolarization. Further, the suppressive effect of cordycepin against $A{\beta}$ + IBO-induced excessive neuronal membrane depolarization and neuronal hyperactivity was blocked by DPCPX (8-cyclopentyl-1,3-dipropylxanthine, an adenosine $A_1$ receptor-specific blocker). Collectively, these results revealed the suppressive effect of cordycepin against the $A{\beta}$ + IBO-induced excitotoxic neuronal insult by attenuating excessive neuronal activity and membrane depolarization, and the mechanism through the activation of $A_1R$ is strongly recommended, thus highlighting the therapeutic potential of cordycepin in AD.

Near-Field Detection of Aβ Proteins Using Micro Beads

  • Lee, Seung-Jun;Sung, Hee-Kyung;Choi, Yo-Han
    • Journal of Sensor Science and Technology
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    • v.21 no.5
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    • pp.319-323
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    • 2012
  • In this paper, we present the possibility of quantification analysis for $A{\beta}$ captured by micro beads using Near-filed detection. In order to evaluate detection efficiency, detected signals were compared with different sizes of micro beads and a varied number of micro beads. Also, $A{\beta}$ deposits and $A{\beta}$ binding to micro beads were measured, therefore, we observed the $A{\beta}$ deposit and light scattering around the surface of micro beads induced by attached $A{\beta}$. This method can be used for quantitative analysis for not only the number of $A{\beta}$, but also the binding ratio of $A{\beta}$ to micro beads.

Potential Role of Ursodeoxycholic Acid in Suppression of Nuclear Factor Kappa B in Microglial Cell Line (BV-2)

  • Joo, Seong-Soo;Won, Tae-Joan;Lee, Do-Ik
    • Archives of Pharmacal Research
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    • v.27 no.9
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    • pp.954-960
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    • 2004
  • Expression of the NF-$textsc{k}$B-dependent genes responsible for inflammation, such as TNF-$\alpha$, IL-1$\beta$, and nitric oxide synthase (NOS), contributes to chronic inflammation which is a major cause of neurodegenerative diseases (i.e. Alzheimer's disease). Although NF-$textsc{k}$B plays a biphasic role in different cells like neurons and microglia, controlling the activation of NF-$textsc{k}$B is important for its negative feedback in either activation or inactivation. In this study, we found that ursodeoxycholic acid (UDCA) inhibited I$textsc{k}$B$\alpha$ degradation to block expression of the NF-$textsc{k}$B-dependent genes in microglia when activated by $\beta$-amyloid peptide (A$\beta$). We also showed that when microglia is activated by $A\beta$42, the expression of A20 is suppressed. These findings place A20 in the category of ' protective ' genes, protecting cells from pro-inflammatory reper-toires induced in response to inflammatory stimuli in activated microglia via NF-$textsc{k}$B activation. In light of the gene and proteins for NF-$textsc{k}$B-dependent gene and inactivator for NF-$textsc{k}$B (I$textsc{k}$B$\alpha$), the observations now reported suggest that UDCA plays a role in supporting the attenuation of the production of pro-inflammatory cytokines and NO via inactivation of NF-$textsc{k}$B. Moreover, an NF-$textsc{k}$B inhibitor such as A20 can collaborate and at least enhance the anti-inflammatory effect in microglia, thus giving a potent benefit for the treatment of neurodegenerative diseases such as AD.uch as AD.

Houttuynia cordata Improves Cognitive Deficits in Cholinergic Dysfunction Alzheimer's Disease-Like Models

  • Huh, Eugene;Kim, Hyo Geun;Park, Hanbyeol;Kang, Min Seo;Lee, Bongyong;Oh, Myung Sook
    • Biomolecules & Therapeutics
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    • v.22 no.3
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    • pp.176-183
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    • 2014
  • Cognitive impairment is a result of dementia of diverse causes, such as cholinergic dysfunction and Alzheimer's disease (AD). Houttuynia cordata Thunb. (Saururaceae) has long been used as a traditional herbal medicine. It has biological activities including protective effects against amyloid beta ($A{\beta}$) toxicity, via regulation of calcium homeostasis, in rat hippocampal cells. To extend previous reports, we investigated the effects of water extracts of H. cordata herb (HCW) on tauopathies, also involving calcium influx. We then confirmed the effects of HCW in improving memory impairment and neuronal damage in mice with Ab-induced neurotoxicity. We also investigated the effects of HCW against scopolamine-induced cholinergic dysfunction in mice. In primary neuronal cells, HCW inhibited the phosphorylation of tau by regulating p25/p35 expression in $A{\beta}$-induced neurotoxicity. In mice with $A{\beta}$-induced neurotoxicity, HCW improved cognitive impairment, as assessed with behavioral tasks, such as novel object recognition, Y-maze, and passive avoidance tasks. HCW also inhibited the degeneration of neurons in the CA3 region of the hippocampus in Ab-induced neurotoxicity. Moreover, HCW, which had an $IC_{50}$ value of $79.7{\mu}g/ml$ for acetylcholinesterase inhibition, ameliorated scopolamine-induced cognitive impairment significantly in Y-maze and passive avoidance tasks. These results indicate that HCW improved cognitive impairment, due to cholinergic dysfunction, with inhibitory effects against tauopathies and cholinergic antagonists, suggesting that HCW may be an interesting candidate to investigate for the treatment of AD.

Neuroprotective Effects and Physicochemical Characteristics of Milk Fortified with Fibroin BF-7 (BF-7 강화 우유의 뇌기능보호 효과 및 물리화학적 특성)

  • Choi, Gooi-Hun;Jo, Mi-Na;Moon, Sun-Hee;Lim, Sung-Min;Jung, A-Ram;Yoon, Yoh-Chang;Paik, Hyun-Dong
    • Food Science of Animal Resources
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    • v.28 no.4
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    • pp.431-436
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    • 2008
  • The impact of storage on the neuroprotective effects against $A\beta$-induced cell death and physicochemical characteristics of milk fortified with BF-7 were investigated. The BF-7 milk exerted protection of neuronal cells SK-N-SH from amyloid beta ($A\beta$)-induced neuronal stress. Our results showed that incubation of the cell with pretreated BF-7 milk, significantly attenuated apoptotic stress by $A\beta$, considered in cell morphology and nucleus shape. The general compositions were maintained consistently in BF-7 fortified milk (BF-7 milk). The BF-7 did not make any disturbance on pH and titratable acidity. The color change was not detected, either. Also, any microorganism had not been detected with more than 7 days storage at $4^{\circ}C$. In sensory evaluation study. the average scores of each sensory attribute were quite similar with plain milk. In conclusion, our results strongly indicate that BF-7 characteristics are quite adequate to be included in milk and BF-7 milk is still working well on neuro-protection, result in enforcing our brain and delaying neurodegeneration.

Comparative study on anti-Alzheimer's effects of herbal medicines treating phlegm (치담(治痰) 한약의 항알츠하이머 효능 비교 연구)

  • Kwak, Chaewon;Choi, Jin Gyu;Kim, Jeong Hee;Oh, Myung Sook
    • The Korea Journal of Herbology
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    • v.34 no.4
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    • pp.9-18
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    • 2019
  • Objectives : It has been known to be correlated between phlegm and dementia from the perspective of oriental medicine, but it is unexplored whether herbal medicines to treat phlegm have pharmacological actions on Alzheimer's disease (AD). The aim of this study was to evaluate and to compare effects of herbal medicines to treat phlegm against AD in vitro. Methods : We selected 11 herbal medicines which treat phlegm and obtained each extract by boiling in 10-fold distilled water for 2 h. And we performed the assay of acetylcholinesterase (AChE) inhibitory effects of 11 herbal extracts. Next, we evaluated neuroprotective effects of them against amyloid $beta_{25-35}$ ($A{\beta}_{25-35}$) plaque-induced toxicity in HT22 mouse hippocampal neuronal cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. To investigate whether they show the anti-inflammatory effects against lipopolysaccharide (LPS), we also measured the levels of nitric oxide (NO) in BV2 microglia cells using griess reagent assay. Results : We found that Gamiyeongsin-hwan (GYH) and Cheonghunhwadam-tang (CHT) exhibited remarkable AChE inhibitory effects. In HT22 cells, Arisaematis Rhizoma, Trichosanthis Semen and Fritillariae Thunbergii Bulbus suppressed $A{\beta}_{25-35}$ plaque-induced neuronal cell death. In BV2 cells, Cheongung-hwan significantly inhibited the increase of NO contents induced by LPS and GYH and CHT showed a tendency to inhibit LPS-induced NO generation. Conclusions : These results suggest that several herbal medicines to treat phlegm showed the significant effects on AChE inhibition, neuroprotection against $A{\beta}_{25-35}$ plaque-induced toxicity, and inhibition of NO generation. Therefore, we demonstrate the possibility that herbal medicines with treating phlegm has effects against AD.

Chongmyung-tang Inhibits the Cytotoxicity of Beta-amyloid in Neuro 2A Neuroblastoma Cells (베타 아밀로이드 유도성 Neuro 2A 세포독성에 대한 총명탕의 효과)

  • Gug Yun Jai;Choi Hyuk;Kim Tae Heon;Kang Hyung Won;Lyu Young Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.5
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    • pp.1418-1425
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    • 2004
  • The water extract of Chongmyung-tang has been traditionally used for treatment of memory-disorder in oriental medicine. This study was designed to investigate the protective mechanisms of Chongmyung-tang on β-amyloid or H₂O₂-induced cytotoxicity in Neuro 2A cells. The water extract of Chongmyung-tang significantly reduced both β-amyloid or H₂O₂-induced cell death and apoptotic characteristics through reduction of intracellular peroxide generation. Also, it inhibited the mitochondrial dysfunction including the disruption of mitochondria membrane permeability transition(MPT) and the modulation in expression of Bcl-2 family proteins in H₂O₂-treated H9c2 cells. Furthermore, pretreatment of quercetin inhibited the activation of caspase-3, in turn, degradation of ICAD/DFF45 were completely abolished in H₂O₂-treated cells. Taken together, that data suggest that the protective effects of the water extract of Chongmyung-tang against β-amyloid induced oxidative injuries may be achieved through modulation of mitochondrial dysfunction.