• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.353-357
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• 2002

We have previously demonstrated that kudzu root extracts have a hypocholesterolemic effect on rats fed diets high in fat and cholesterol. To further elucidate the mechanism involved, in this study we investigated the effect of water extracts of kudzu root, Pueraria radix, on the production of apolipoprotein B$_{100}$ (APo B$_{100}$) in HepG$_2$ liver cells and secretion of apolipoprotein B$_{48}$ (Apo B$_{48}$) in Caco$_2$ cells. Human cell lines, HepG$_2$ liver cells and Caco$_2$ intestinal epithelial cells, were grown with various concentrations (0%, 0.5%, 1.0%, 1.5%, 2.0%) of water extracts of kudzu root in the media. The kudzu root extract decreased Apo B$_{100}$ production and secretion. Treatment of HeP G$_2$ cells with the kudzu root extract also significantly decreased the intracellular total and free cholesterol concentration, and also decreased esterified cholesterol but was only significant at the highest dose of 2%. Apo B$_{48}$ production, but not secretion, from enterocytes was lowered by the kudzu root extracts. This research provided evidence that the hypocholesterolemic properties of kudzu root may be a consequence of decreased production and secretion of Apo B$_{100}$ in the liver and Apo B$_{48}$ in the intestine.

• Preventive Nutrition and Food Science
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• v.4 no.2
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• pp.145-151
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• 1999

Apolipoprotein B-100 (apo B-100) is an important component in plasma low density lipoproteins (LDL). It function as the ligand for the LDL receptor in peripheral cells. The LDLs are removed from the circulation by both high-affinity receptor-mediated and receptor-independant pathways. LDLs are heterogeneous in their lipid content, size and density and certain LDL subspecies increase risk of atherosclerosis due to differences in the conformation of apo B in the particle. In the present study , surface and core peptide fraction of Apo B-100 have been characterized by comparing peptide-mapping and fluorescence spectroscopy. Surface fragments of apo B-100 were generated by digestion of LDL with either trypsin , pronase, or pancreatin elastase. Surface fractions were fractionated on a Sephadex G-50 column. The remaining core fragments were delipidated and redigested with the above enzymes, and the resulting core peptides were compared with surface peptides. Results from peptide-mapping by HPLC showed pronase-digestion was more extensive than trypsin -digestion to remove surface peptide fraction from LDL. Fluorescence spectra showed that core fractions contained higher amount of tryptophan than surface fractions, and it indicated that core fraction wa smore hydrophobic than surface fractions. A comparison of the behavior of the core and surface provided informations about the regions of apo B-100 involved in LDL metabolism and also about the structural features concerning the formation of atherosclerosis.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.284-288
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• 2003

In this study, we investigated the effects of green tea and Pueraria radix tea on the production of Apo B$_{100}$ in Hep G$_2$ liver cells and on the expression of the low density lipoprotein (LDL) receptor. Treatment with green tea resulted in a 60.7% decrease on the Apo B$_{100}$ concentration in Hep G$_2$ cells. Pueraria radix tea decreased Apo B$_{100}$ concentration by 63.5% in Hep G$_2$ cells. Green tea and Pueraria radix tea significantly decreased Apo B$_{100}$ concentration by 64.8% and 61.8%, respectively, in the media. Treatment of the cells with green tea and Pueraria radix tea also significantly decreased the intracellular total cholesterol, but total cholesterol concentrations in the media increased by 26.4% (green tea) and 23.6% (Pueraria radix tea) above that measured in the media of control cells. The addition of green tea and Pueraria radix to the media of the Hep Gz cells increased the LDL receptor binding activities by 84.1% and 79.4%, respectively.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1845-1849
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• 2004

Apolipoprotein B-100 (Apo-B100) is a major protein component for low density lipoproteins (LDL). A number of mimetic peptides of Apo-B100 were screened from the phase-displayed random peptide library by utilizing monoclonal antibody (B9). Mimetic peptide for B9 epitope against apo B-100 was CRNVPPIFNDVYWIAF (pB1). From the BLAST search, the mimetic peptide pB1 had 40% homology with apo B-100. As a result of the structural determination of this mimotope using homo/hetero nuclear 2D-NMR techniques and NMR-based distance geometry (DG)/molecular dynamic (MD) computations, DG structure had low penalty value of 0.3-0.6 ${\AA}^2$ and the total RMSD was 0.5-1.5 ${\AA}. Moreover, pB1 structure included a weak $3_{10}$-helix from $Ile^7$,/TEX> to $Trp^{13}$.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.3
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• pp.95-101
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• 2016

Apolipoprotein B-100 (Apo-B100) is a major component of low density lipoprotein (LDL). Apo B-100 protein has 4,536 amino acid sequence and these amino acids are classified into peptide groups A to G with subsequent 20 amino acids (P1-P302). The peptide groups were act as immunoglobulin (Ig) antigens which oxidized via malondialdehyde (MDA). The mimetic peptide P1 (EEEMLENVSLVCPKDAT RFK) out of D-group peptides carrying the highest value of IgG antigens were selected for structural studies that may provide antigen specificity. Circular Dichroism (CD) spectra were measured for peptide secondary structure in the range of 190-250 nm. Experimental results show that P1 exhibit partial of ${\beta}-sheet$ and random coil structure. Homonuclear (COSY, TOCSY, NOESY) 2D-NMR experiments were carried out for NMR signal assignments and structure determination for P1. On the basis of these completely assigned NMR spectra and distance data, distance geometry (DG) and Molecular dynamics (MD) were carried out to determine the structures of P1. The proposed structure was selected by comparisons between experimental NOE spectra and back calculated 2D NOE results from determined structure showing acceptable agreement. The total Root-Mean-Square-Deviation (RMSD) value of P1 obtained upon superposition of all atoms was in the range $0.33{\AA}$. The solution state P1 has mixed structure of ${\beta}-sheet$ (Glu[1] to Cys[12]) and random coil (Pro[13] to Lys[20]). These NMR results are well consistent with secondary structure from experimental results of circular dichroism. Structural studies based on NMR may contribute to the studies of atherosclerosis and observed conformational characteristics of apo B-100 in LDL using monoclonal antibodies.

• Animal cells and systems
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• v.2 no.3
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• pp.367-370
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• 1998

Two molecular species of apolipophorin-III (spoLp-III) were purified from the last instar larval hemolymph of Galleria mellonella by gel permeation chromatography (Sephadex G-100), ion exchange chromatography (DE-52), heat treatment (90C for 30 min) and Mono S FPLC, and were named apoLp-III-a and apoLp-lll-b, respectively. They were indistinguishable by SDS-PAGE but could be separated by native PAGE. The molecular mass of apoLp-III determined by SDS-PAGE was approximately 18 kDa. The N-terminal amino acid sequence of apoLp-III-b revealed high similarities with the apoLp-III from Manduca sexta.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.4
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• pp.136-142
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• 2020

Apolipoprotein B-100 (apo B-100), the main protein component that makes up LDL (Low density lipoprotein), consists of 4,536 amino acids and serves to combine with the LDL receptor. The oxidized LDL peptides by malondialdehyde (MDA) or acetylation in vivo were act as immunoglobulin (Ig) antigens and peptide groups were classified into 7 peptide groups with subsequent 20 amino acids (P1-P302). The biomimetic peptide P99 (KGTYG LSCQR DPNTG RLNGE) out of B-group peptides carrying the highest value of IgM antigens were selected for structural studies that may provide antigen specificity. Circular Dichroism (CD) spectra were measured for peptide secondary structure in the range of 190-260 nm. Experimental results show that P99 has pseudo α-helice and random coil structure. Homonuclear (COSY, TOCSY, NOESY) 2D-NMR experiments were carried out for NMR signal assignments and structure determination for P99. On the basis of these completely assigned NMR spectra and proton distance information, distance geometry (DG) and molecular dynamic (MD) were carried out to determine the structures of P99. The proposed structure was selected by comparisons between experimental NOE spectra and back-calculated 2D NOE results from determined structure showing acceptable agreement. The total Root-Mean-Square-Deviation (RMSD) value of P99 obtained upon superposition of all atoms were in the set range. The solution state P99 has mixed structure of pseudo α-helix and β-turn(Gln[9] to Thr[13]). These NMR results are well consistent with secondary structure from experimental results of circular dichroism. Structural studies based on NMR may contribute to the prevent oxidation studies of atherosclerosis and observed conformational characteristics of apo B-100 in LDL using monoclonal antibodies.

• Journal of the Korean Magnetic Resonance Society
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• v.25 no.4
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• pp.58-63
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• 2021

Apolipoprotein B-100 (apo B-100), the main protein component that makes up LDL (Low density lipoprotein), consists of 4,536 amino acids and serves to combine with the LDL receptor. The oxidized LDL peptides by malondialdehyde (MDA) or acetylation in vivo act as immunoglobulin (Ig) antigens and peptide groups were classified into 7 peptide groups with subsequent 20 amino acids (P1-P302). The biomimetic peptide P143 (IALDD AKINF NEKLS QLQTY) out of C-group peptides carrying the highest value of IgG antigens were selected for structural studies that may provide antigen specificity. Experimental results show that P143 has β-sheet in Ile[1]-Asn[9] and α-helice in Gln[16]-Tyr[20] structure. Homonuclear 2D-NMR (COSY, TOCSY, NOESY) experiments were carried out for NMR signal assignments and structure determination for P143. On the basis of these completely assigned NMR spectra and proton distance information, distance geometry (DG) and molecular dynamic (MD) were carried out to determine the structures of P143. The proposed structure was selected by comparisons between experimental NOE spectra and back-calculated 2D NOE results from determined structure showing acceptable agreement. The total Root-Mean-Square-Deviation (RMSD) value of P143 obtained upon superposition of all atoms were in the set range. The solution state P143 has a mixed structure of pseudo α-helix and β-turn(Phe[10] to Glu[12]). These results are well consistent with calculated structure from experimental data of NOE spectra. Structural studies based on NMR may contribute to the prevent oxidation studies of atherosclerosis and observed conformational characteristics of apo B-100 in LDL using monoclonal antibodies.

• Korean Journal of Poultry Science
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• v.31 no.2
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• pp.73-78
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• 2004

The effect of supplemental yellow ${\beta}$-8-Apo-carotenoic acid ethyl ester (ACA) (0~300mg/kg feed) on its accumulation in each body part of laying hens and the pigmentation in egg yolk was determined. The chickens used in this study were 78-wk-old ISA brown laying hens. ACA significantly affected the color of the bodies of laying hens. The yellowness ($b^*$) but not the redness ($a^*$) and, the lightness ($L^*$) of the skin, and muscle as measured by a colorimeter significantly (P < 0.05) increased when ACA was fed at 50~100 mg/kg feed. Egg yolk color was also significantly affected by feeding ACA longer than 2 days (P < 0.05) at the levels higher than 50 mg/kg feed. Conclusively, ACA is recommended for improving yellowness of skin.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1214-1221
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• 1998

The study was carried out to investigate the antioxidant effects of ethanol, methanol, and water extracts or fractions of ethanol extract of Ligularia fischeri on low density lipoprotein(LDL) and ethanol extract was further fractionated. The methanol extract and ethyl acetate fraction showed strong antioxidant effect with 71.7% (13.36 nmol/mg) and 95% (1.35 nmol/mg) inhibition in the presence of $15\;{\mu}g/mL$, respectively. In the value of malondialdehyde(MDA) with oxidation time, ethanol, methanol and water extract in the presence of $25\;{\mu}g/mL$ inhibited the oxidation up to 4h incubation and ethyl acetate fraction showed strong antioxidant effect up to 8h incubation. Also, the ethanol, methanol and water extract showed antioxidant effects in the agarose gel electrophoresis test. The conjugated diene formation by lipid oxidation with addition of $Cu^{2+}$ in the Ligularia fischeri extracts and their fractions was decreased approximately 1.1 to 2.8 times and 2.2 to 3.2 times, respectively compared to control. In the degradation of apo B-100 by oxidation using SDS-PAGE, ethanol, methanol and water extract showed similar degradation band pattern compared to that of native LDL band. Apo B-100 contents using densitometer were 77.8, 92.5% and 82.3% in the ethanol, methanol and water extract, respectively, compared to 100% of native LDL. In the meanwhile, apo B-100 contents in hexane, ethyl acetate and water fraction were 38.8, 94.5 and 65.5% respectively. This results indicated that ethyl acetate fraction showed the strongest antioxidant effect on MDA value or apo B-100 contents of LDL.