• 대한의생명과학회지
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• 제15권4호
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• pp.287-293
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• 2009

Phospholipase D (PLD) is an enzyme hydrolyzing phosphatidylcholine to phosphatidic acid (PA) and choline. We investigated the involvement of PLD1 in the uptake of norepinephrine (NE) in PC12 cells, pheochromocytoma cells. NE uptake was specific in PC12 cells because nomifensine, a specific blocker of NE transporter, blocked NE uptake. Inhibition of PLD function in PC12 cells by the treatment of butanol suppressed the NE uptake. In contrast, overexpression of PLD1 in PC12 cells increased NE uptake efficiently. These results suggest that PLD activity is involved in NE uptake. We explored the action mechanism of PLD in NE uptake. PA phosphatase inhibitor, propranolol, blocks the formation of PKC activator diacylglycerol from PA. Propranolol treatment to PC12 cells blocked dramatically the uptake of NE. Specific PKC inhibitors, GF109203X and Ro31-8220, blocked NE uptake. Taken together, we suggest for the first time that PLD1 activity is involved in NE uptake via the activation of PKC.

• 식물조직배양학회지
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• 제27권5호
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• pp.375-377
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• 2000

It is now generally accepted that a phosphoinositide cycle is involved in the transduction of a variety of signals in plant cells. In animal cells, the hydrolysis of phosphatidyl-4,5-bisphosphate catalysed by phosphatidylinositol - specific phospholipase C yields to D-myo-inositol - 1,4,5-trisphosphate and diacylglycerol, which are well known second messengers. The binding of InsP$_3$to a receptor located on the endoplasmic reticulum triggers a calcium release from the endoplasmic reticulum. We have detected and partially characterised key components of phosphoinositide signaling. First, tobacco microsomal fraction and plasma membrane PI-PLC. Consecutively, using a radioligand binding assay we have identified a $Ca^{2+}$ -dependent high affinity InsP$_3$binding site in microsomal membrane fraction vesicle preparation and then we have measured inositol-1,4,5-trisphosphate induced calcium release from tobacco microsomal fraction. These findings suggest that phosphoinositide signaling system is present and operates in the tobacco suspension culture.e.

• Journal of Plant Biotechnology
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• 제39권4호
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• pp.242-252
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• 2012

Seed storage oils are essential resources for not only human and animal diets but also industrial applications. The primary goal of this study was to increase seed oil content through comparative analysis of two seed-specific promoters, AtFAE1 from Arabidopsis Fatty Acid Elongase 1 gene and BnNapin from Brassica napus seed storage protein gene. AtWRI1 and AtDGAT1 genes encoding an AP2-type transcription factor and a Diacylglycerol Acyltransferase 1 enzyme, respectively, were expressed under the control of AtFAE1 and BnNapin promoters in Arabidopsis. The total seed oil content in all transgenic plants was increased by 8-11% compared with wild-type seeds. The increased level of oil content in AtWRI1 and AtDGAT1 transgenic lines under the control of both promoters was similar, although the activity of the BnNapin promoter is much stronger than that of AtFAE1 promoter in the mature stage of developing seeds where storage oil biosynthesis occurs at a maximum rate. This result demonstrates that the AtFAE1 promoter as well as the BnNapin promoter can be used to increase the seed oil content in transgenic plants.

• 한국동물학회지
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• 제37권1호
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• pp.76-87
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• 1994

High density lipophorin-L (HDLP-L) was purified from the hemolymph of Bombyx modi using KBr density gradient ultracentrifugation and gel permeation chromatographv (Sephadex G-2001. Lipophorin has native molecular weight of 730 Nd and consists of Apo-Lp I and Apo-Lp II with molecular weights of 250 Kd and 90 Kd, respectively. Lp contains large amounts of glutamine & glutamic acid, threonine, leucine but small amounts of cysteic acid & oxidized cystine, tyrosine, methionine. Lp also contains diacylglycerol, cholesterol, phosphatidylcholine, and phosphatidylethanolamine. Anti-lipophorin showed positive reaction with fat body and ovarial extracts and also revealed immunological identity with lipophorin of Fall webworm, Hyphantria cunea. Lipophorin maintains constant level during larval and pupal stapes but greatlv increases during adult stage in both male and female. Apo-Lp III was purified from adult hemolymph. Hemolymph was subjected to KBr ultracentrifusation and Lp-free fraction was submitted to cation exchange chromatosraphy after ammonium sulfate precipitation. Apo-Lp III has molecular weight of 17 Kd, and similar amino acid composition ar those of other species Lp but contains high amounts of tryptophan which other are tacking in.

• Archives of Pharmacal Research
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• 제21권4호
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• pp.452-457
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• 1998

Three compounds, 5-(acetoxymethyl)-5-(hydroxymethyl)-3-tetradecyl-2,5-dihydro-2-furanone (3), 5-(acetoxymethyl)-5-(hydroxymethyl)-3,3-dihexyltetrahydro-2-furanone (4) and 5-(acetoxymethyl)-5-(hydroxymethyl)-3,3-dioctyltetrahydro-2-furanone (5), were designed and synthesized as surrogates of the ultrapotent DAG analogue, 5-(acetoxymethyl)-5-(hydroxymethyl) 3-[(Z)-tetradecylideneltetrahydro-2-furanone (1), a compound that showed high affinity for PKC-$\alpha$ ($K_1$=35 nM) in a competition binding assay with [$^3H$-20]phorbol-12,13-dibutyrate (PDBU). In an attempt to overcome the problem of generating geometrical E- and Z- isomers, as encountered with 1, the double bond was moved to an endocyclic location as in 3, or an additional alkyl chain was appended to C3 to give the corresponding 3,3-dialkyl saturated lactones (4 and 5). The lactone was constructed from glycidyl-4-methoxyphenyl ether in 5 steps. The target compounds showed reduced binding affinities for PKC-.alpha. with $K_{i}$ values of 192 nM (3), 4,829 nM (4), and 2,812 nM (5), respectively. These results indicate that constrained DAG analogues having a tetrahydro-2-furanone template are effectively discriminated by PKC-(X in terms of the direction of the long alkyl chain connected to the 3-position.n.

• Journal of Microbiology and Biotechnology
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• 제27권9호
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• pp.1617-1627
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• 2017

Dietary approaches using structured lipids, including medium-chain fatty acids and diacylglycerols, have been adopted for the prevention of obesity-induced chronic inflammation. In an extension to previous studies, medium-chain fatty acid-diacylglycerol enriched dietary oil (MCDG) was prepared by interesterification of canola oil and medium-chain fatty acid-triacylglycerols. The consequent MCDG product was applied to RAW264.7 macrophages followed by the assessment of multiple inflammatory responses. Compared with conventionally used canola and olive oil controls, MCDG suppressed macrophage phagocytosis, as assessed by the uptake of microsphere beads. Furthermore, the production of IL-6 and $TNF-{\alpha}$, transcription of COX-2 and iNOS, and expression of CD80 on cell surfaces were downregulated by MCDG in LPS-stimulated macrophages. Subsequently, differentiated 3T3-L1 adipocytes were evaluated for proinflammatory cytokine production and lipid accumulation. IL-6 production was marginally affected and lipid accumulation was inhibited by MCDG. Taken together, these results suggest that MCDG has potential as an alternative oil for cooking in order to prevent obesity-induced inflammation.

• 한국식품영양과학회지
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• 제20권5호
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• pp.473-478
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• 1991

After the glycolipid(GL) and phospolipid (PL) of flint corn during a growth process were fractionated by silicic acid column chromatography (SACC), the GL and PL of polar lipids were separated by thin layer chromatography (TLC)and quantitative by TLC scanner and the fatty acid composition in polar lipids were determined by gas chromatography (GC). Of the GL in polar lipids were separated by TLC, monoglycosyl diacylglycerol (8.3~29.2%) was the major component, and monoglycosyl ceramide, monoglycosyl sterol were also found as minor components. Of the PL, phosphatidyl choline (27.2~29.5%) and phosphatidyl inositol (42.9~79.1%) were the major components, and phosphatidyl ethanolamine and cardiolipin were also persont in the PL. The major fatty acids in the GL were oleic(27.1~37.1%), linoleic (13.2~35.7%) and palmitic (22.5~25.6%) acids. The major fatty acids in the PL were palmitic (46.5~52.3%), heptadecanoic (23.0~25.1%) and oleic(7.2~14.6%) and GL contained a higher percentage of unsa-turated fatty acids, but PL presented that of the saturated fatty acids.

• Korean Circulation Journal
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• 제48권12호
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• pp.1097-1119
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• 2018

Although elevated serum low-density lipoprotein-cholesterol (LDL-C) is without any doubts accepted as an important risk factor for cardiovascular disease (CVD), the role of elevated triglycerides (TGs)-rich lipoproteins as an independent risk factor has until recently been quite controversial. Recent data strongly suggest that elevated TG-rich lipoproteins are an independent risk factor for CVD and that therapeutic targeting of them could possibly provide further benefit in reducing CVD morbidity, events and mortality, apart from LDL-C lowering. Today elevated TGs are treated with lifestyle interventions, and with fibrates which could be combined with omega-3 fatty acids. There are also some new drugs. Volanesorsen, is an antisense oligonucleotid that inhibits the production of the Apo C-III which is crucial in regulating TGs metabolism because it inhibits lipoprotein lipase (LPL) and hepatic lipase activity but also hepatic uptake of TGs-rich particles. Evinacumab is a monoclonal antibody against angiopoietin-like protein 3 (ANGPTL3) and it seems that it can substantially lower elevated TGs levels because ANGPTL3 also regulates TGs metabolism. Pemafibrate is a selective peroxisome proliferator-activated receptor alpha modulator which also decreases TGs, and improves other lipid parameters. It seems that it also has some other possible antiatherogenic effects. Alipogene tiparvovec is a nonreplicating adeno-associated viral vector that delivers copies of the LPL gene to muscle tissue which accelerates the clearance of TG-rich lipoproteins thus decreasing extremely high TGs levels. Pradigastat is a novel diacylglycerol acyltransferase 1 inhibitor which substantially reduces extremely high TGs levels and appears to be promising in treatment of the rare familial chylomicronemia syndrome.

• The Journal of Korean Physical Therapy
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• 제20권3호
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• pp.61-68
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• 2008

Purpose: Protein kinase C (PKC) is a member of a family of serine/threonine kinases that are activated by diacylglycerol (DG) and PKC stimulants. PKC play a key role in signal transduction, including muscle contraction, cell migration, apoptosis, cell proliferation and differentiation. However, the mechanism relating mitogen-activated protein kinases (MAPKs) and PKC, especially in the volume-dependent hypertensive state, remains unclear. Methods: In the present study, I investigated the relationship between PKC and MAPKs for isometric contraction, PKC translocation, and enzymatic activity from normotensive sham-operated rats (NSR) and aldosterone-analogue deoxycorticosterone acetate (DOCA) hypertensive rats (ADHR). Results: Systolic blood pressure was significantly increased in ADHR than in NSR. Physiological salt solution (PSS)-induced resting tension and the intracellular $Ca^{2+}$ concentration ([$Ca^{2+}{_i}$]) were different in the ADHR and NSR. The expression of PKC$\alpha$, PKC$\beta$II, PKC$\delta$, PKC$\varepsilon$ and PKC$\xi$ were different between the cytoplasmic and membranous fractions. However, expression of the PKC isoforms did not differ for the ADHR and NSR. The use of 12-deoxyphorbol 13-isobutyrate (DPB, a PKC stimulant) induced isometric contraction in $Ca^{2+}$-free medium, which was diminished in muscle strips from ADHR as compared to NSR. Increased vasoconstriction and phosphorylation induced by the use of 1 ${\mu}$M DPB were inhibited by treatment with 10 ${\mu}$M PD098059 and 10 ${\mu}$M SB203580, inhibitors of extracellular-regulated protein kinase 1/2 (ERK1/2) and p38 MAPK from ADHR, respectively. Conclusion: These results suggest that the development of aldosterone analogue-induced hypertension is associated with an altered blood pressure, resting tension, [$Ca^{2+}{_i}$], and that the $Ca^{2+}$-independent contraction evoked by PKC stimulants is due to the activation of ERK1/2 and p38 MAPK in volume-dependent hypertension. Therefore, it is suggested that PKC activity affects volume-dependent hypertension and the need to develop cardiovascular disease-specialized physical therapy.

• 한국환경과학회지
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• 제26권11호
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• pp.1275-1284
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• 2017

Acyltransferase (AT) catalyzes the transfer of an acyl moiety from acyl-coenzyme A (acyl-CoA) to an acceptor. ATs play important roles in the maintenance of homeostasis in the human body and have been linked to various diseases; therefore, several ATs have been proposed as potential targets for the treatment or prevention of such diseases. The AT family includes acyl-CoA:cholesterol AT (ACAT), diacylglycerol AT, and monoacylglycerol AT for the metabolism of lipids. Furthermore, recent molecular biological studies revealed the existence of their isozymes with distinct functions in the body. ACAT plays a critical role in the formation of cholesteryl esters from cholesterol and fatty acids, and is a potential target for treating hypercholesterolemia. During an experiment designed to discover biologically active compounds from herbal medicines, we isolated two known guaianolide sesquiterpene lactones from Chrysanthemum boreale Makino (Compositae). The lactones were characterized from their spectroscopic data (NMR, IR, MASS). These compounds were subjected to ACAT inhibition assay. Here, we report the isolation and structural elucidation of the compounds 8-o-acetyl-2-methoxy-10-hydroxy-3,11(13)-guaiadiene-12,6-olide and 8-acetyl-3,10-hydroxy-4(15),11(13)-guaiadiene-12,6-olide. In the ACAT inhibition assay, compound 1 showed strong inhibitory activity, with an $IC_{50}$ value $45{\mu}g/mL$, whereas compound 2 did not exhibit significant inhibitory activity with an over $100{\mu}g/mL$.