Naslov
Study of structural properties and oxidation dynamics of lipoproteins from different plasma phenotypes

Autori
Krilov, Dubravka ; Kosović, Marin ; Brnjas-Kraljević, Jasminka ; Gamulin, Ozren ; Serec, Kristina

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Advances in Single - Molecule Research for Biology and Nanoscience / - Linz : Johannes Kepler University Linz, Institute for Biophysics, 2012, Poster 8-9

Skup
XIV Annual Linz Winter Workshop

Mjesto i datum
Linz, Austrija, 03.02.2012. - 07.02.2012

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Plasma phenotype; lipoproteines; FTIR; EPR

Sažetak
Three classes of plasma lipoproteins, HDL, LDL and VLDL were isolated from patients with two different plasma phenotypes: phenotype A, with larger LDL particles and smaller VLDL particles, and phenotype B, with smaller dense LDL particles and larger VLDL particles. This second one is also called atherogenic phenotype. FT-IR spectra of lipoproteins of two phenotypes were recorded in the frequency region 4000-600 cm-1 from dried samples on ZnSe window. The spectral characterization of protein and lipid bands, from earlier analysis [1] was used for the comparison of spectral differences within the same class of lipoprotein, from different plasma phenotypes. The differences were observed in fingerprint region, in C=O stretching band from lipids and amide I and amide II bands from apolipoproteins. Significant differences were observed also at lower frequencies, mostly in bands from stretching and bending vibrations of lipid chains. The differences within spectra of LDL and VLDL samples were more pronounced than those within spectra of HDL samples. It is known that larger VLDL particles containing increased number of triglycerides in core (B) are precursors of small LDL particles (B) in which the conformation of apo B and lipid composition is changed in comparison with those from A [2]. These structural differences were reflected in our spectra. Oxidation dynamics was studied by ESR spectroscopy, using spin probe CTPO for measuring the decrease in concentration of molecular oxygen, due to its spending in lipid oxidation series, as was done in earlier studies [3]. The oxidation was initiated by adding small amounts of copper ions into lipoprotein solution. The rate of relatively fast oxidation in LDL was only slightly different in A and B LDL samples. In HDL and VLDL samples the oxidation was slower than in LDL samples, and even slower in VLDL than HDL. In both these lipoproteins, the oxidation of B samples was faster than that of A samples. These results confirm the higher tendency of B plasma lipoproteins to oxidation. However, almost the same rate of oxidation of two LDL phenotypes probably is the consequence of rather rapid process within it is not possible to distinguish the difference.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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