• Title/Summary/Keyword: ${\beta}$-Peptide

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Inhibitory Effect of Bee Venom on Lipopolysaccharide-induced Memorial Impairment and Acetylcholine Esterase, Secretase Activity

  • Kwon, Dae-Hyun;Song, Ho-Sueb
    • Journal of Acupuncture Research
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    • v.23 no.2
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    • pp.33-46
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    • 2006
  • Alzheimer's disease (AD) is the most prevalent form of neurodegenerative disease associated with aging in the human population. This disease is characterized by the extracellular deposition of beta-amyloid peptide $(A{\beta})$ in cerebral plaques. $A{\beta}$ is derived from the ${\beta}-amyloid$ precursor protein (APP) by the enzymes, ${\beta}-$ and ${\eta}o-secretase$. Compounds that ${\beta}-$ or ${\eta}o-secretase$ inhibit activity, can reduce the production of $A{\beta}$ peptides, and thus have therapeutic potential in the treatment of AD. Increasing body of evidence has been demonstrated that Bee Venom(BV) Acupuncture could compete with complex protein involving in multiple step of $NF-{\kappa}B$ activation and exert the anti-inflammatory potential of combined inhibition of the prostanoid and nitric oxide synthesis systems by inhibition of IKK and $NF-{\kappa}B$. In this study, I investigated possible effects of BV on memory dysfunction caused by lipopolysaccharide (LPS) and $A{\beta}$ through inhibition of secretases activities and $A{\beta}$ aggregation. I examined the improving effect of BV on the LPS (2.5 mg/Kg, i.p.)-induced memory dysfunction using passive avoidance response and water maze tests in the mice. BV (0.84, $1.67\;{\mu}g/ml$) reversed the LPS-induced memorial dysfunction in dose dependent manner. BV also dose-dependently attenuated LPS-induced ${\beta}$ and ${\eta}o-secretase$ activities in cerebral cortex and hippocampus of the mice brain. This study therefore suggests that BV acupuncture method may be useful for prevention of development or progression of AD.

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Protective Effect of Green Tea Extract on Amyloid $\beta$ peptide-induced Neurotoxicity (아밀로이드베타 펩타이드 유도성 신경세포독성에 대한 녹차 추출물의 보호 효과)

  • Kim, Young-In;Park, Jeong-Yoon;Choi, Soo-Jung;Kim, Jae-Kyeom;Jeong, Chang-Ho;Choi, Sung-Gil;Lee, Seung-Cheol;Cho, Sung-Hwan;Heo, Ho-Jin
    • Food Science and Preservation
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    • v.15 no.5
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    • pp.743-748
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    • 2008
  • Amyloid $\beta$ peptide ($A{\beta}$) is known to increase oxidative stress in nerve cells, leading to apoptosis that is characterized by free radical formation and lipid peroxidation. Neurodegenerative diseases such as Alzheimer's disease (AD) are characterized by large deposits of $A{\beta}$ in the brain. In our study, neuronal protective effects of green tea, along with water activity (0.813), and leaf storage periods (fresh leaf, or leaf stored for up to 4 weeks) were investigated. We measured protective effects against $A{\beta}$-induced cytotoxicity in neuron-like PC12 cells. Powdered green tea was extracted with distilled water at $70^{\circ}C$ for 5 min, and this extract was freeze-dried and stored at $-20^{\circ}C$ until use. In cell viability assays using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), the fresh extract, and that obtained after 1 week of leaf storage, showed the best protective effects against $A{\beta}$-induced neurotoxicity. As oxidative stress causes membrane breakdown, the protective effect of green tea extracts was investigated using lactate dehydrogenase (LDH) and trypan blue exclusion assays. LDH release into the medium was inhibited (by 20-25%) in all tests. In addition, all green tea extracts (fresh, or stored before extraction for up to 4 weeks) showed better cell protective effects ($93.3{\pm}1.8-96.2{\pm}2.4$) than did vitamin C ($91.0{\pm}1.6$), used as a positive control. The results suggest that effectiveness of green tea extracts falls with prolonged leaf storage.

Bitter Peptides Derived from ${\alpha}_{s1}-and\;{\beta}-Casein$ Digested with Alkaline Protease from Bacillus subtilis (Bacillus subtilis의 염기성 프로테아제로 분해된 ${\alpha}_{s1}$- 및 ${\beta}$-카세인에서 분리된 쓴 맛 펩타이드)

  • Sohn, Kyung-Hyun;Lee, Hyong-Joo
    • Korean Journal of Food Science and Technology
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    • v.20 no.5
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    • pp.659-665
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    • 1988
  • The ${\alpha}_{s1}$-and ${\beta}$-casein were purified by DEAE-cellulose chromatography and digested with alkaline protease from Bacillus subtilis. Bitter fractions from the hydrolyzates were isolated using n-butanol extraction, Sephadex G-25 gel chromatography, and high performance liquid chromatography. Peptide mixtures were separated by reverse-phase octadecyl silica column with linear gradient of 0-80% acetonitrile containing 0.1% trifluoroacetic acid. Major peaks were combined from replicate chromatographies and the bitterness of each peak was evaluated. The bitter-tasting peaks were rechromatograpied until isolated peaks were obtained. Three different bitter peptides(BP-I, BP-II, BP-III) were obtained from the ${\alpha}_{s1}$-casein hydrolyzate. BP-I was eluted at 34% acetonitrile and BP-II, 35%, BP-III, 26%, respectively. Two bitter peptides(BP-IV, BP-V) were isolated from the ${\beta}-casein$ hydrolyzate: BP-IV was eluted at 40% acetonitrile and BP-V, 42%. BP-V was the most hydrophobic peptide in the five bitter peptides. However, BP-I and BP-II tasted more bitter than BP-IV and BP-V.

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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.

$RpoB_{127-135}$ Peptide Derived from Mycobacterium tuberculosis is Processed and Presented to HLA-$A^*0201$ Restricted CD8+ T Cells via an Alternate HLA-I Processing Pathway

  • Cho, Jang-Eun;Cho, Sang-Nae;Cho, Sungae
    • Biomedical Science Letters
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    • v.20 no.4
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    • pp.250-255
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    • 2014
  • Mycobacterium tuberculosis (MTB) resides and replicates inside macrophages. In our previous report, we reported that CD8+ T cell-mediated immune responses specific for the peptide derived from MTB RNA polymerase beta-subunit ($RpoB_{127-135}$) could be induced in TB patients expressing HLA-$A^*0201$ subtype. In order to examine whether $RpoB_{127-135}$ specific CD8+ T cells can recognize MTB infected macrophages in vitro, CD8+ T cell lines specific for $RpoB_{127-135}$ peptide were generated from peripheral blood mononuclear cells (PBMCs) of healthy HLA-$A^*0201$ subjects by in vitro immunization technique. In this study, we observed $RpoB_{127-135}$ specific CD8+ T cells could recognize and destroy macrophages infected with MTB for 2 to 4 days. $RpoB_{127-135}$ specific CD8+ T cell immune response was inducible from PBMC of healthy subjects expressing HLA-$A^*0206$ subtype, one of HLA-A2 supertype members. Next, we investigated the HLA-I processing mechanism of $RpoB_{127-135}$ peptide in MTB infected macrophages. As a result, the presentation of the MTB derived epitope peptide, $RpoB_{127-135}$, to CD8+ T cells was not inhibited by the treatment with brefeldin-A (ER-Golgi transport inhibitor) or lactacystin (proteasome inhibitor), which blocks the classical HLA-I processing pathway. However, $RpoB_{127-135}$ specific CD8+ T cell activity was blocked either by the blocking agent for the endocytosis (cytochalasin D) or by the blocking antibody (W6/32) for HLA-I molecules. Therefore, the $RpoB_{127-135}$ peptide may be processed by accessing the alternate HLA-I processing pathway. Understanding the processing and presentation mechanisms of the MTB derived proteins will help to improve the efficacy of vaccines and the efficiency of therapeutic agents for TB.

Defining B Cell Epitopes of Ovalbumin for the C57BL/6 Mice Immunized with Recombinant Mycobacterium smegmatis

  • Kim, Hyo-Joon;Lee, Yang-Min;Hwang, Joon-Sung;Won, Ho-Shik;Kim, Bok-Hwan
    • BMB Reports
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    • v.32 no.5
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    • pp.461-467
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    • 1999
  • Recombinant Mycobacterium smegmatis expressing ovalbumin was used to immunize C57BL/6(H-$2^b$) mice, and the humoral immunity against recombinant ovalbumin was analyzed. Antibodies were purified by denatured ovalbumin-conjugated affinity chromatography. The epitopes of the antibodies were screened with a random peptide library displayed on the tip of fUSE5 filamentous phage pIII minor coat proteins. Two peptides, IRLADR and SPGAEV, were selected predominantly by the recognition of purified antibodies using biopanning methods. The composition of the peptide sequence with the primary structure of OVA revealed that the peptide sequence analogizes to INEAGR, part of the $^{323}ISQAVHAAHAEINEAGR^{339}$ sequence previously reported as the antigenic determinant for murine Band also Th cell epitopes (I-$A^d$ binding). Also, the structures of these mimotopes obtained from restrained molecular dynamic computations resulted in the formation of a $\beta$-turn proven to be a secondary structure of the parent peptide within the ovalbumin molecule, enabling us to confirm the structural similarity. This study demonstrates that immunization with recombinant M. smegmatis can generate neutralizing antibodies identical with those induced by the administration of natural antigenic proteins and supports the potential use of mycobacteria as vaccine delivery vehicles.

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Cytokine mRNA Expression in the Small Intestine of Weanling Pigs Fed Diets Supplemented with Specialized Protein or Peptide Sources

  • Zhao, J.;Harper, A.F.;Webb, K.E. Jr.;Kuehn, L.A.;Gilbert, E.;Xiao, X.;Wong, E.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.12
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    • pp.1800-1806
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    • 2008
  • Cytokines play a central role in the mucosal immune response and are involved in regulation of nutrient absorption, metabolism and animal growth. This study investigated the effect of diet manipulation with specialized protein or peptide sources on expression of cytokine (IL-1, IL-6, IL-10, and TNF-${\alpha}$) mRNA abundance in different intestinal regions and at different ages post-weaning in piglets. A total of 48 (17 days of age, $6.16{\pm}0.34kg\;BW$) weanling pigs were fed either a corn-soy/whey protein basal diet, the basal diet supplemented with spray-dried plasma protein (SDPP), or the basal diet supplemented with $Peptiva^{(R)}$, a hydrolyzed marine plant protein. A fourth treatment group was fed the SDPP diet, but the feed intake level was limited (SDPP-LF). Pigs were killed at 3 and 10 d, and intestinal cytokine mRNA was measured by real-time PCR using the relative quantification method. The SDPP-LF group exhibited an increased TNF-${\alpha}$ mRNA abundance compared with the ad libitum SDPP group (p<0.05). The TNF-${\alpha}$ and IL-10 mRNA abundance increased from the proximal to distal part of the intestine, and the mRNA abundance was greater (p<0.01) in the distal intestine as compared with the proximal and middle intestine. The cytokines IL-1-${\beta}$, IL-10 and TNF-${\alpha}$ mRNA abundance also increased from d3 to d10 postweaning (p<0.01). In summary, restricted feeding increased the TNF-${\alpha}$ mRNA abundance in the small intestine, however neither SDPP nor peptide supplementation affected cytokine mRNA expression. Abundance of mRNA for most cytokines examined in this study increased with age post-weaning, suggesting that during 10 d after weaning the mucosal immune system is still under development.

EFFECT OF CAPSAICIN AND EUGENOL ON ICGRP (IMMUNOREACTIVE CALCITONIN GENE-RELATED PEPTIDE) RELEASE FROM RAT LUMBAR SPINAL CORD. (백서 척수에서 Capsaicin과 Eugenol이 iCGRP (immunoreactive calcitonin gene-related peptide) 분비 조절에 미치는 영향.)

  • 오원만;김원재;최남기;박상원;황인남;김선헌
    • Restorative Dentistry and Endodontics
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    • v.26 no.5
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    • pp.436-442
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    • 2001
  • Neuropeptide such as calcitonin gene-related peptide and substance P may mediate neurogenic inflammation, but little is known about the regulation of neuropeptide release from rat spinal cord. Eugenol has been reported to reduce odontogenic pain and is known to have a structure similar to capsaicin, a potent stimulant of certain nociceptors. This study was done to examine the effect of capsaicin and eugenol on immunoreactive calcitonin gene-related peptide (iCGRP) release from rat spinal cord and whether eugenol regulates capsaicin-sensitive release of iCCRP or it evokes capsaicin-sensitive release of iCGRP. The dor-sal half of rat lumbar spinal cord was chopped into 200$\mu$m slices. They were superfused (500$\mu$l/min) in vitro with an oxygenated Kreb's buffer. The EC$_{50}$ of capsaicin on iCGRP release was measured. Eugenol (600$\mu$M and 1.2mM) and vehicle (0.02% 2-hydroxyl-$\beta$-cyclodextrin) were administered prior to stimulation of rat lumbar spinal cord with capsaicin. The amount of iCGRP release from rat lumbar spinal cord was measured by radioimmunoassay. The results were as follows : 1. iCGRP release from rat lumbar spinal cord was dependent on concentration of capsaicin. The EC$_{50}$ of capsaicin on iCGRP release was 3$\mu$M. 2. In the vehicle treated group, capsaicin (3$\mu$M) evoked a 14-fold increase over basal iCGRP level. 3. Administration of 600$\mu$M and 1.2mM eugenol evoked a 2.2-fold increase and a 2.3-fold increase over basal iCGRP level respectively. 4. Administration of 600$\mu$M and 1.2mM eugenol increased capsaicin evoked release of iCGRP by more than 50%. These results indicate that eugenol evoke CGRP release from central nervous system and potentiate the pain-inducing action of capsaicin on it.

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Peptides derived from high voltage-gated calcium channel β subunit reduce blood pressure in rats

  • Hyung Kyu Kim;Jiyeon Jun;Tae Wan Kim;Dong-ho Youn
    • The Korean Journal of Physiology and Pharmacology
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    • v.27 no.5
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    • pp.481-491
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    • 2023
  • The β subunits of high voltage-gated calcium channels (HGCCs) are essential for optimal channel functions such as channel gating, activation-inactivation kinetics, and trafficking to the membrane. In this study, we report for the first time the potent blood pressure-reducing effects of peptide fragments derived from the β subunits in anesthetized and non-anesthetized rats. Intravenous administration of 16-mer peptide fragments derived from the interacting regions of the β1 [cacb1(344-359)], β2 [cacb2(392-407)], β3 [cacb3(292-307)], and β4 [cacb4(333-348)] subunits with the main α-subunit of HGCC decreased arterial blood pressure in a dose-dependent manner for 5-8 min in anesthetized rats. In contrast, the peptides had no effect on the peak amplitudes of voltage-activated Ca2+ current upon their intracellular application into the acutely isolated trigeminal ganglion neurons. Further, a single mutated peptide of cacb1(344-359)-cacb1(344-359)K357R-showed consistent and potent effects and was crippled by a two-amino acid-truncation at the N-terminal or C-terminal end. By conjugating palmitic acid with the second amino acid (lysine) of cacb1(344-359)K357R (named K2-palm), we extended the blood pressure reduction to several hours without losing potency. This prolonged effect on the arterial blood pressure was also observed in non-anesthetized rats. On the other hand, the intrathecal administration of acetylated and amidated cacb1(344-359)K357R peptide did not change acute nociceptive responses induced by the intradermal formalin injection in the plantar surface of rat hindpaw. Overall, these findings will be useful for developing antihypertensives.

[ $A_1$ ] Receptor-mediated Protection against Amyloid Beta-induced Injury in Human Neuroglioma Cells

  • Cho, Yong-Woon;Jung, Hyun-Ju;Kim, Yong-Keun;Woo, Jae-Suk
    • The Korean Journal of Physiology and Pharmacology
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    • v.11 no.2
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    • pp.37-43
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    • 2007
  • Adenosine has been reported to provide cytoprotection in the central nervous systems as well as myocardium by activating cell surface adenosine receptors. However, the exact target and mechanism of its action still remain controversial. The present study was performed to examine whether adenosine has a protective effect against $A{\beta}$-induced injury in neuroglial cells. The astrocyte-derived human neuroglioma cell line, A172 cells, and $A{\beta}_{25{\sim}35}$ were employed to produce an experimental $A{\beta}$-induced glial cell injury model. Adenosine significantly prevented $A{\beta}$-induced apoptotic cell death. Studies using various nucleotide receptor agonists and antagonists suggested that the protection was mediated by $A_1$ receptors. Adenosine attenuated $A{\beta}$-induced impairment in mitochondrial functional integrity as estimated by cellular ATP level and MTT reduction ability. In addition, adenosine prevented $A{\beta}$-induced mitochondrial permeability transition, release of cytochrome c into cytosol and subsequent activation of caspase-9. The protective effect of adenosine disappeared when cells were pretreated with 5-hydroxydecanoate, a selective blocker of the mitochondrial ATP-sensitive $K^+$ channel. In conclusion, therefore we suggest that adenosine exerts protective effect against $A{\beta}$-induced cell death of A172 cells, and that the underlying mechanism of the protection may be attributed to preservation of mitochonarial functional integrity through opening of the mitochondrial ATP-sensitive $K^+$ channels.