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LipidBank: Its recent changes
Chemistry and Physics of Lipids 149S (2007) S74–S91
Abstracts
Posters—Miscellaneous
PO 118
Subtle differences in the hydration of phospholipid aggregates as a function of temperature and structure may be studied by SP-EPR Marilene Alves, Miroslav Peric Department of Physics and Astronomy, California State University at Northridge, USA The spin probe electron paramagnetic resonance (SPEPR) method has been successfully used to study the physical properties of phospholipids and their aggregates (Cevc, 1993). Recently, by employing nonlinear least-squares spectral fitting, it has been possible to extract high precision EPR parameters, such as hyperfine coupling spacings and rotational times, from the fast motional EPR spectra. The hydrophobic spin probe 2,2,6,6-tetramethyl-piperidin-1oxyl-4-yl-octadecanoate (TEMPO-stearate) was studied in a variety of fully hydrated phospholipid vesicles. The hyperfine coupling spacing is used to estimate the effective water concentration in the polar shell of vesicles, while the rotational correlation times give information on the motion of the spin probe. The experimental results show that the effective water concentration in the polar shell of negatively charged dimyristoylphosphatidylglycerol (DMPG) vesicles is about 4 M greater than in the polar shell of zwitterionic dimyristoylphosphatidylcholine (DMPC) vesicles. Studies of a series of phosphatidylcholine (PC) vesicles with phospholipids of different acyl chain lengths from 14 to 18 carbons and lipid PC having unsaturated 18 carbon acyl chains have shown that the effective water concentration decreases by about 0.5 M for an increase of two carbons in the chain, and increases noticeably with hydrocarbon 0009-3084/$ – see front matter doi:10.1016/j.chemphyslip.2007.06.168
chain unsaturation. The differences in effective water concentration in the polar shells of phospholipid vesicles measured by the SP-EPR method appear to be in good agreement with the values obtained by X-ray scattering and NMR. Supported by NIH 5 3 S06 GM48680-10S1. Reference Cevc, G., 1993. Phospholipids Handbook. Marcel Dekker, New York.
doi:10.1016/j.chemphyslip.2007.06.169 PO 119
LipidBank: Its recent changes Masanori Arita 1 , Etsuko Yasugi 2 , Yousuke Seyama 3 , Masahiro Nishijima 4 1 Graduate
School of Frontier Sciences, University of Tokyo and PRESTO-JST, Japan; 2 Graduate School of Medicine, University of Tokyo, Japan; 3 National Institution for Academic Degrees and University Evaluation, Japan; 4 National Institute of Health Science, Japan LipidBank (http://www.lipidbank.jp/), the official database of the Japanese Conference on the Biochemistry of Lipids (JCBL), is a publicly free database of natural lipids including fatty acids, glycerolipids, sphingolipids, steroids, and various vitamins. The database offers more than 6000 unique molecular structures (ChemDraw and MOL format), their lipid names (common and IUPAC names), spectral information (mass, UV, IR, NMR and others), and most importantly, literature information. All molecular information is manually curated and approved by experts in lipid research. The database is undergoing a significant
Abstracts / Chemistry and Physics of Lipids 149S (2007) S74–S91
update in its structure and database management system. For more than 3500 metabolites, whose structure was reexamined at the atomic level, the following properties were automatically recalculated: molecular mass, formula, and the number of chemical groups and the type of structural backbone. This procedure realized the automated, structure-based classification of lipids, and its effectiveness is under study. doi:10.1016/j.chemphyslip.2007.06.170 PO 120
Cytotoxic effect of 7-ketocholesterol on HepG2 cells in the presence of ethanol Migiwa Asano, Hideyuki Nushida, Yasuhiro Ueno Department of Legal Medicine, Kobe University Graduate School of Medicine, Japan Oxidative stress is recognized to be a key element in the pathogenesis of alcoholic liver disease. We previously demonstrated 7-ketocholesterol to be present at elevated concentrations in the ethanol administrated rat liver and 7-ketocholesterol is thus considered to be a useful molecular indicator of oxidative stress. On the other hand, the exogenous addition of 7-ketocholesterol has been reported to cause cell death in several lines of cultured cells. We herein investigated the cytotoxic effects of 7-ketocholesterol on the HepG2 human hepatoma cell line, while also attempting to determine whether such effects were enhanced in the presence of ethanol. HepG2 cells were incubated in an EME medium for 24 h in the presence of 7-ketocholesterol and/or ethanol and the cell viability was assessed by lactate dehydrogenase (LDH) leakage and 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide (MTT) reduction. Ethanol (50–300 mM) demonstrated no effect on the cell viability, whereas 7-ketocholesterol (25–200 M) decreased cell viability in a dose-dependent manner. Although 25 M of 7-ketocholesterol alone did not significantly reduce cell viability, the effect was enhanced by the simultaneous addition of ethanol. These results suggest that 7-ketocholesterol is not only a marker of oxidative stress but also a potent promoter of ethanol-induced liver injury. doi:10.1016/j.chemphyslip.2007.06.171 PO 121 Withdrawn.
S75
PO 122
Electromechanics: An analytic solution for graded biological cell under inhomogeneous field Joe Kin Lok Chan Department of Physics, The Chinese University of Hong Kong, Hong Kong, China Electromechanics of graded material has been established recently to study the effective response of inhomogeneous graded spherical particles under an external homogeneous ac electric field (Wei et al., 2006; Dong et al., 2005). Such particles having a complex dielectric profile vary along the radius of the particles. The gradation in the colloidal particles is modeled by assuming both the dielectric and conductivity profile varying along the radius. However, external field may not be homogeneous in reality. In this talk, the exact analytical solutions of inhomogeneous colloidal particle under an inhomogeneous field of an oscillating electric dipole moment by multi-pole expansion would be presented. It shows good agreement with numerical simulations (Fan et al., 2006). Our exact results may be applied to graded biological cell suspensions, as their interiors must be inhomogeneous in nature. References Dong, L., Karttunen, M., Yu, K.W., 2005. Phys. Rev. E 72 (art. no. 016613). Fan, C.Z., Huang, J.P., Yu, K.W., 2006. J. Phys. Chem. B 110, 25665–25670. Wei, E.-B., Dong, L., Yu, K.W., 2006. J. Appl. Phys. 99, 054101.
doi:10.1016/j.chemphyslip.2007.06.173 PO 123
In vivo evaluation of bile acid synthesis in patients with cerebrotendinous xhantomatosis Marina Del Puppo 1 , Federica Corna 1 , Maria Teresa Dotti 2 , Emma De Fabiani 3 , Marzia Galli Kienle 1 1 DIMS,
University of Milano Bicocca, Italy; of Neurological Sciences, University of Siena, Italy; 3 Department of Pharmacological Sciences, University of Milano, Italy
2 Department
Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder caused by mutations in the CYP27A1 gene (Moghadasian, 2004) coding for the enzyme 27-hydroxylase which catalyzes the initial step of the “alternative” pathway in the conversion of cholesterol to bile acids. This pathway has been reported to
Abstracts
Posters—Miscellaneous
PO 118
Subtle differences in the hydration of phospholipid aggregates as a function of temperature and structure may be studied by SP-EPR Marilene Alves, Miroslav Peric Department of Physics and Astronomy, California State University at Northridge, USA The spin probe electron paramagnetic resonance (SPEPR) method has been successfully used to study the physical properties of phospholipids and their aggregates (Cevc, 1993). Recently, by employing nonlinear least-squares spectral fitting, it has been possible to extract high precision EPR parameters, such as hyperfine coupling spacings and rotational times, from the fast motional EPR spectra. The hydrophobic spin probe 2,2,6,6-tetramethyl-piperidin-1oxyl-4-yl-octadecanoate (TEMPO-stearate) was studied in a variety of fully hydrated phospholipid vesicles. The hyperfine coupling spacing is used to estimate the effective water concentration in the polar shell of vesicles, while the rotational correlation times give information on the motion of the spin probe. The experimental results show that the effective water concentration in the polar shell of negatively charged dimyristoylphosphatidylglycerol (DMPG) vesicles is about 4 M greater than in the polar shell of zwitterionic dimyristoylphosphatidylcholine (DMPC) vesicles. Studies of a series of phosphatidylcholine (PC) vesicles with phospholipids of different acyl chain lengths from 14 to 18 carbons and lipid PC having unsaturated 18 carbon acyl chains have shown that the effective water concentration decreases by about 0.5 M for an increase of two carbons in the chain, and increases noticeably with hydrocarbon 0009-3084/$ – see front matter doi:10.1016/j.chemphyslip.2007.06.168
chain unsaturation. The differences in effective water concentration in the polar shells of phospholipid vesicles measured by the SP-EPR method appear to be in good agreement with the values obtained by X-ray scattering and NMR. Supported by NIH 5 3 S06 GM48680-10S1. Reference Cevc, G., 1993. Phospholipids Handbook. Marcel Dekker, New York.
doi:10.1016/j.chemphyslip.2007.06.169 PO 119
LipidBank: Its recent changes Masanori Arita 1 , Etsuko Yasugi 2 , Yousuke Seyama 3 , Masahiro Nishijima 4 1 Graduate
School of Frontier Sciences, University of Tokyo and PRESTO-JST, Japan; 2 Graduate School of Medicine, University of Tokyo, Japan; 3 National Institution for Academic Degrees and University Evaluation, Japan; 4 National Institute of Health Science, Japan LipidBank (http://www.lipidbank.jp/), the official database of the Japanese Conference on the Biochemistry of Lipids (JCBL), is a publicly free database of natural lipids including fatty acids, glycerolipids, sphingolipids, steroids, and various vitamins. The database offers more than 6000 unique molecular structures (ChemDraw and MOL format), their lipid names (common and IUPAC names), spectral information (mass, UV, IR, NMR and others), and most importantly, literature information. All molecular information is manually curated and approved by experts in lipid research. The database is undergoing a significant
Abstracts / Chemistry and Physics of Lipids 149S (2007) S74–S91
update in its structure and database management system. For more than 3500 metabolites, whose structure was reexamined at the atomic level, the following properties were automatically recalculated: molecular mass, formula, and the number of chemical groups and the type of structural backbone. This procedure realized the automated, structure-based classification of lipids, and its effectiveness is under study. doi:10.1016/j.chemphyslip.2007.06.170 PO 120
Cytotoxic effect of 7-ketocholesterol on HepG2 cells in the presence of ethanol Migiwa Asano, Hideyuki Nushida, Yasuhiro Ueno Department of Legal Medicine, Kobe University Graduate School of Medicine, Japan Oxidative stress is recognized to be a key element in the pathogenesis of alcoholic liver disease. We previously demonstrated 7-ketocholesterol to be present at elevated concentrations in the ethanol administrated rat liver and 7-ketocholesterol is thus considered to be a useful molecular indicator of oxidative stress. On the other hand, the exogenous addition of 7-ketocholesterol has been reported to cause cell death in several lines of cultured cells. We herein investigated the cytotoxic effects of 7-ketocholesterol on the HepG2 human hepatoma cell line, while also attempting to determine whether such effects were enhanced in the presence of ethanol. HepG2 cells were incubated in an EME medium for 24 h in the presence of 7-ketocholesterol and/or ethanol and the cell viability was assessed by lactate dehydrogenase (LDH) leakage and 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide (MTT) reduction. Ethanol (50–300 mM) demonstrated no effect on the cell viability, whereas 7-ketocholesterol (25–200 M) decreased cell viability in a dose-dependent manner. Although 25 M of 7-ketocholesterol alone did not significantly reduce cell viability, the effect was enhanced by the simultaneous addition of ethanol. These results suggest that 7-ketocholesterol is not only a marker of oxidative stress but also a potent promoter of ethanol-induced liver injury. doi:10.1016/j.chemphyslip.2007.06.171 PO 121 Withdrawn.
S75
PO 122
Electromechanics: An analytic solution for graded biological cell under inhomogeneous field Joe Kin Lok Chan Department of Physics, The Chinese University of Hong Kong, Hong Kong, China Electromechanics of graded material has been established recently to study the effective response of inhomogeneous graded spherical particles under an external homogeneous ac electric field (Wei et al., 2006; Dong et al., 2005). Such particles having a complex dielectric profile vary along the radius of the particles. The gradation in the colloidal particles is modeled by assuming both the dielectric and conductivity profile varying along the radius. However, external field may not be homogeneous in reality. In this talk, the exact analytical solutions of inhomogeneous colloidal particle under an inhomogeneous field of an oscillating electric dipole moment by multi-pole expansion would be presented. It shows good agreement with numerical simulations (Fan et al., 2006). Our exact results may be applied to graded biological cell suspensions, as their interiors must be inhomogeneous in nature. References Dong, L., Karttunen, M., Yu, K.W., 2005. Phys. Rev. E 72 (art. no. 016613). Fan, C.Z., Huang, J.P., Yu, K.W., 2006. J. Phys. Chem. B 110, 25665–25670. Wei, E.-B., Dong, L., Yu, K.W., 2006. J. Appl. Phys. 99, 054101.
doi:10.1016/j.chemphyslip.2007.06.173 PO 123
In vivo evaluation of bile acid synthesis in patients with cerebrotendinous xhantomatosis Marina Del Puppo 1 , Federica Corna 1 , Maria Teresa Dotti 2 , Emma De Fabiani 3 , Marzia Galli Kienle 1 1 DIMS,
University of Milano Bicocca, Italy; of Neurological Sciences, University of Siena, Italy; 3 Department of Pharmacological Sciences, University of Milano, Italy
2 Department
Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder caused by mutations in the CYP27A1 gene (Moghadasian, 2004) coding for the enzyme 27-hydroxylase which catalyzes the initial step of the “alternative” pathway in the conversion of cholesterol to bile acids. This pathway has been reported to