Oxidized phospholipids induce phase separation in lipid vesicles

被引:47
作者
Megli, FM [1 ]
Russo, L [1 ]
Sabatini, K [1 ]
机构
[1] Univ Bari, Dipartmento Biochim & Biol Mol, I-70126 Bari, Italy
关键词
lipoperoxidation; phospholipid bilayer; lipid phase separation; EPR; spin labelling; membrane fluidity;
D O I
10.1016/j.febslet.2005.07.022
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The thermal behaviour of phospholipid multilamellar vesicles (MLV) made of various molar percentages of DPPC and LPPC, containing also oxidized LPPC (LPPCox), was studied by use of EPR spectroscopy and n-DSPC spin label in order to determine variations in the membrane fluidity brought about by lipid oxidation. Experimental variables were temperature, ranging from 4 to 44 degrees C, and molar percentage composition of DPPC/LPPC/LPPCox ternary mixture. We found that the presence of LPPCox in a percentage higher than both normal phospholipids' heavily hindered membrane formation, while lower percentage of the oxidized lipid with higher DPPC percentages yielded two-components EPR spectra, showing the presence of two different fluidity domains, indicative of membrane phase separation. When LPPC was the dominant lipid in the ternary mixture, simple EPR spectra were observed, indicating homogeneity of MLV membranes. Phase separation observed in the presence of LPPCox was better visible at lower temperature (12 degrees C or less), and almost disappeared with increasing temperature (36 degrees C or more). Furthermore, the correlation time of 16-DSPC in ternary mixture MLVs with higher LPPC percentage (homogeneous membranes) was not affected by the presence of LPPCox, while it normally increased upon DPPC percentage increase, as readily calculated from the EPR spectra featuring simple bands at 24 degrees C. It is concluded that oxidized lipid induces phase separation in more rigid DPPC-rich membranes, while leaving fluidity unaffected in more fluid LPPC-rich membranes, and at higher temperature. (c) 2005 Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.
引用
收藏
页码:4577 / 4584
页数:8
相关论文
共 24 条
[1]  
Boss W.F., 1974, ANAL BIOCHEM, V64, P289
[2]   Dynamic molecular structure of DPPC-DLPC-cholesterol ternary lipid system by spin-label electron spin resonance [J].
Chiang, YW ;
Shimoyama, Y ;
Feigenson, GW ;
Freed, JH .
BIOPHYSICAL JOURNAL, 2004, 87 (04) :2483-2496
[3]  
CHIANG YW, 2005, BIOCHIM BIOPHYS ACTA, V1669, P99
[4]   Effects of mitochondrial respiratory stimulation on membrane lipids and proteins: an electron paramagnetic resonance investigation [J].
Gabbita, SP ;
Subramaniam, R ;
Allouch, F ;
Carney, JM ;
Butterfield, DA .
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES, 1998, 1372 (02) :163-173
[5]   Electron spin resonance characterization of liquid ordered phase of detergent-resistant membranes from RBL-2H3 cells [J].
Ge, MT ;
Field, KA ;
Aneja, R ;
Holowka, D ;
Baird, B ;
Freed, JH .
BIOPHYSICAL JOURNAL, 1999, 77 (02) :925-933
[6]   Domain formation in a fluid mixed lipid bilayer modulated through binding of the C2 protein motif [J].
Hinderliter, A ;
Almeida, PFF ;
Creutz, CE ;
Biltonen, RL .
BIOCHEMISTRY, 2001, 40 (13) :4181-4191
[7]   STUDIES ON PHOSPHATIDYLCHOLINE VESICLES . FORMATION AND PHYSICAL CHARACTERISTICS [J].
HUANG, CH .
BIOCHEMISTRY, 1969, 8 (01) :344-+
[8]   ON THE PRINCIPLES OF FUNCTIONAL ORDERING IN BIOLOGICAL-MEMBRANES [J].
KINNUNEN, PKJ .
CHEMISTRY AND PHYSICS OF LIPIDS, 1991, 57 (2-3) :375-399
[9]   Lipid bilayers as osmotic response elements [J].
Kinnunen, PKJ .
CELLULAR PHYSIOLOGY AND BIOCHEMISTRY, 2000, 10 (5-6) :243-250
[10]   LIPID MODEL MEMBRANES - CHARACTERIZATION OF MIXED PHOSPHOLIPID VESICLES [J].
LITMAN, BJ .
BIOCHEMISTRY, 1973, 12 (13) :2545-2554