• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.8
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• pp.724-731
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• 2006

We investigated the electrochemical properties for Langmuir-Blodgett (LB) films mixed with 4-octyl-4'-(5-carboxylpentamethyleneoxy)azobenzene (denoted as 8A5H) and phospholipid(L-a-dimyristoylphosphatidylcholine, denoted as DMPC and L-a-dilauroylphosphayidylcholine, denoted as DLPC). The LB films of 8A5H, 8A5H-DMPC and 8A5H-DLPC mixture monolayers were deposited by using the LB method on the indium tin oxide(ITO) glass. The electrochemical properties measured by using cyclic voltammetry with a three-electrode system, an Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode at various concentrations(0.1, 0.5, and 1.0 mol/L) of $NaClO_4$ solution. A measuring range was reduced from initial potential to -1350 mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rates were 50, 100, 150 and 200 mV/s, respectively. As a result, LB films of 8A5H and 8A5H-DLPC mixture monolayers appeared irreversible process caused by only the oxidation current from the cyclic voltammogram and LB films of 8A5H-DMPC monolayer mixture was found to be caused by a reversible oxidation-reduction process.

• Archives of Pharmacal Research
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• v.20 no.3
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• pp.218-224
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• 1997

Platelet-activating factor (PAF) acetylhydrolase, which removes the acetyl moiety at the sn-2 position, has been found in human amniotic fluid. We purified this enzyme by ammonium sulfate precipitation, and sequential use of DEAE-Sepharose CL-6B, hydroxyapatite, chelating-Sepharose, and Mono Q column chromatographies. This enzyme exhibited broad pH optima and was unaffected by EDTA. Partially purified enzyme had a molecular weight of approximately 34 kDa on SDS-PAGE. In addition, the enzyme activity was inhibited by either diisopropylfluorophosphate(DFP) or p-bromophenacylbromide (p-BPB), suggesting that this enzyme possesses active serine and histidine residues. The enzyme showed similar activity towards PAF and oxidatively modified phosphatidylcholine, but didn't hydrolyze phosphatidylcholine or phosphatidylethanolamine with a long chain fatty acyl group at sn-2 position.

• Journal of the Korean Applied Science and Technology
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• v.22 no.4
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• pp.315-322
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• 2005

We investigated the electrochemical properties for Langmuir-Blodgett (LB) films mixed with 4-octyl-4'-(5-carboxylpentamethyleneoxy)azobenzene (denoted as 8A5H) and $phospholipid(L-{\alpha}-dimyristoylphosphatidylcholine$, denoted as DMPC). LB films of 8A5H monolayer and 8A5H-DMPC were deposited by using the Langmuir-Blodgett method on the indium tin oxide(ITO) glass. The electrochemical properties measured by using cyclic voltammetry with a three_electrode system, an Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode at various concentrations(0.1, 0.5, and 1.0mol/L) of $NaClO_4$ solution. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650mV and measured to the initial point. The scan rates were 50, 100, 150 and 200mV/s, respectively. As a result, LB films of 8A5H monolayer appeared irreversible process caused by only the oxidation current from the cyclic voltammogram and LB films of 8A5H-DMPC mixture were found to be caused by a reversible oxidation-reduction process.

• Journal of Ginseng Research
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• v.16 no.3
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• pp.222-227
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• 1992

Unlike carbohydrats and fats, alcohol is essentially foreign to the body and it is known that the body get rid of it by oxidizing alcohol maily in the liver. Acetaldehyde is produced during ethanol metabolism and is known to be oxidized mainly by aldehyde dehydrogenase (ALDH). ALDH activity was found mainly in the mitochondrial fraction but a significant ALDH activity was also present in microsomal and cytosol fraction. Wistar rats (150~200 g, male) were given freely with 12% ethanol (Control) and/or 12% ethanol containing 0.1% ginseng saponins (Test) instead of water for 6 days and the liver was analyzed. ALDH activities of both control and test group were lower than that of normal group but test AkDH was less inhibited than control. ADH activies of both control and test were slightly higher than that of normal group but our previous data showed that it became gradually steady after prolonged ethanol feeding. MEOS activities of both control and test group were much higher than that of normal group. MEOS enzymes are inducible but the activity of test group was greatly higher than that of control. Ethanol containing [1-i4C] ethanol (5 $\mu$Ci) was injected to the above three groups and 30 min later, the distribution of radioactivity of hepatic lipids was investigated. Radioactivities of hepatic lipids of both control and test group were higher than that of normal group, however, that of test group was much lower than that of control. Analysis of individual lipids showed that phospholipid biosynthesis was significantly impaired and fatty acid and triglycerides biosynthesis were greatly stimulated. However, it was realized that the saponin prevented phospholipid biosynthesis depression and the increase of triglyceride biosynthesis considerably. It seemed that the saponin might stimulate ADH, ALDH and MEOS and the acetaldehyde formed would be removed faster. The excess hydrogen can be shunt more quickly into lipid biosynthesis. Electron microscopic observation showed that the hepatic cell of control group was si gnificantly damaged. Mitochondria were swollen and rough endoplasmic reticulum were dilated, however, hepatocytes of test group were not damaged.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.874-877
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• 2004

We carried out this subject to observe electrochemical properties of 1,2-dioleoyl-sn- glycero-3-phosphocholine(DOPC) mixed with fatty acid containing azobenzene group by using cyclic voltammetry with a three-electrode system, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode in $NaClO_4$ solution. We investigated the photoisomerization and electrochemical property of the organic ultra thin film of fatty acid containing azobenzene was prepared on the hydrophilic ITO(idium tin oxide) glass plate by LB method. As a result, the absorption spectra of BASH and DOPC of mixture LB films was induced to photoisomerization by alternating irradiation of ultraviolet and visible light. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rate were 50, 100, 150 and 200 mV/s. As a results, LB films of BASH-DMPC appeared reversible process caused by the reduction-oxidation current from the cyclic voltammogram.

• BMB Reports
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• v.50 no.6
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• pp.323-328
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• 2017

Lysophosphatidylcholine (LPC) is a major phospholipid component of oxidized low-density lipoprotein (ox-LDL) and is implicated in its atherogenic activity. This study investigated the effects of LPC on cell viability, intracellular calcium homeostasis, and the protective mechanisms of chlorogenic acid (CGA) in human umbilical vein endothelial cells (HUVECs). LPC increased intracellular calcium ($[Ca^{2+}]_i$) by releasing $Ca^{2+}$ from intracellular stores and via $Ca^{2+}$ influx through store-operated channels (SOCs). LPC also increased the generation of reactive oxygen species (ROS) and decreased cell viability. The mRNA expression of Transient receptor potential canonical (TRPC) channel 1 was increased significantly by LPC treatment and suppressed by CGA. CGA inhibited LPC-induced $Ca^{2+}$ influx and ROS generation, and restored cell viability. These results suggested that CGA inhibits SOC-mediated $Ca^{2+}$ influx and ROS generation by attenuating TRPC1 expression in LPC-treated HUVECs. Therefore, CGA might protect endothelial cells against LPC injury, thereby inhibiting atherosclerosis.

• BMB Reports
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• v.41 no.8
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• pp.560-567
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• 2008

The importance of lipids in cell signaling and tissue physiology is demonstrated by the many CNS pathologies involving deregulated lipid metabolism. One such critical metabolic event is the activation of phospholipase $A_2$ ($PLA_2$), which results in the hydrolysis of membrane phospholipids and the release of free fatty acids, including arachidonic acid, a precursor for essential cell-signaling eicosanoids. Reactive oxygen species (ROS, a product of arachidonic acid metabolism) react with cellular lipids to generate lipid peroxides, which are degraded to reactive aldehydes (oxidized phospholipid, 4-hydroxynonenal, and acrolein) that bind covalently to proteins, thereby altering their function and inducing cellular damage. Dissecting the contribution of $PLA_2$ to lipid peroxidation in CNS injury and disorders is a challenging proposition due to the multiple forms of $PLA_2$, the diverse sources of ROS, and the lack of specific $PLA_2$ inhibitors. In this review, we summarize the role of $PLA_2$ in CNS pathologies, including stroke, spinal cord injury, Alzheimer's, Parkinson's, Multiple sclerosis-Experimental autoimmune encephalomyelitis and Wallerian degeneration.

• Nutrition Research and Practice
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• v.18 no.2
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• pp.194-209
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• 2024

BACKGROUND/OBJECTIVES: High levels of plasma low-density lipoprotein (LDL) cholesterol are an important determinant of atherosclerotic lesion formation. The disruption of cholesterol efflux or reverse cholesterol transport (RCT) in peripheral tissues and macrophages may promote atherogenesis. The aim of the current study was to examine whether bioactive ellagic acid, a functional food component, improved RCT functionality and high-density lipoprotein (HDL) function in diet-induced atherogenesis of apolipoproteins E (apoE) knockout (KO) mice. MATERIALS/METHODS: Wild type mice and apoE KO mice were fed a high-cholesterol Paigen diet for 10 weeks to induce hypercholesterolemia and atherosclerosis, and concomitantly received 10 mg/kg ellagic acid via gavage. RESULTS: Supplying ellagic acid enhanced induction of apoE and ATP-binding cassette (ABC) transporter G1 in oxidized LDL-exposed macrophages, facilitating cholesterol efflux associated with RCT. Oral administration of ellagic acid to apoE KO mice fed on Paigen diet improved hypercholesterolemia with reduced atherogenic index. This compound enhanced the expression of ABC transporters in peritoneal macrophages isolated from apoE KO mice fed on Paigen diet, indicating increased cholesterol efflux. Plasma levels of cholesterol ester transport protein and phospholipid transport protein involved in RCT were elevated in mice lack of apoE gene, which was substantially reduced by supplementing ellagic acid to Paigen diet-fed mice. In addition, ellagic acid attenuated hepatic lipid accumulation in apoE KO mice, evidenced by staining of hematoxylin and eosin and oil red O. Furthermore, the supplementation of 10 mg/kg ellagic acid favorably influenced the transcriptional levels of hepatic LDL receptor and scavenger receptor-B1 in Paigen diet-fed apoE KO mice. CONCLUSION: Ellagic acid may be an athero-protective dietary compound encumbering diet-induced atherogenesis though improving the RCT functionality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.195-201
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• 1998

Anchor Engraulis japonica was fermented with $10\%$ and $20\%$ salt at $10^{\circ}C$ ($10\%$ 5A) and $20^{\circ}C$ ($20\%$ SA), respectively, and the changes in lipid content, fatty acid composition and lipid oxidation was observed for 105 days. Peroxide value (POV) in $10\%$ SA reached to the maximum (46.4 meq/kg) on 30 days of fermentation, while in $20\%$ SA, it reached the maximum (54.7 meq/kg) on 45 days of fermentation, and then decreased in both samples during fermentation. Thiobarbituric acid values revealed a similar tendency with the change of POV during the fermentation. These results indicated that lipid of the anchovy was oxidized faster in lower salt than high salt in the early stage. Total lipid (TL) content during the fermentation for 105 days decreased approximately $16\%$ in $10\%$ SA and approximately $33\%$ in $20\%$ SA. Phospholipid (PL) content also decreased in both samples and the content of neutral lipid (NL) was unchanged in $10\%$ SA, while it decreased in the same amount as PL in $20\%$ SA. The prominent fatty acids in TL of the anchovy sample were 14 : 0, 16 : 0, 16 : In-7, 18 : in-9, 20 5n-3 and 22 : 6n-3. After fermentation for 105 days, approximately $87\%$ and $67\%$ of the prominent fatty acids remained in $10\%$ SA and $20\%$ SA, respectively, but the kind of the fatty acids was unchanged.

• Journal of the Korean Applied Science and Technology
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• v.31 no.1
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• pp.44-49
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• 2014

We were investigated by cyclic voltammetry to the stability through the electrochemical characteristics of phospholipid(L-${\alpha}$-phosphatidylethanolamine, LAPE) monolayer LB films. LAPE monolayer LB films was deposited by the LB method on the indium tin oxide(ITO) glass. The electrochemical properties was measured by cyclic voltammetry with a three-electrode system in 0.5 N, 1.0 N, 1.5 N and 2.0 N $KClO_4$ solution. The measuring range is continuously oxidized to 1650 mV, with an initial potential of -1350 mV was reduced. Scanning rates of 50, 100, 150, 200, and 250 mV/s was set. As a result, LB monolayer films of LAPE was appeared on irreversible processes by the oxidation current from the cyclic voltammogram. Diffusion coefficient (D) of LAPE was calculated 195, 15.9, 5.75, 1.38 and $0.754cm^2s^{-1}{\times}10^{-9}$ at 0.01 N, 0.05 N, 0.10 N, 0.15 N and 0.20 N $KClO_4$ solutions, respectively.