Biphasic effects of acetaldehyde-biogenic amine condensation products on membrane fluidity

Authors
Citation
H. Tsuchiya, Biphasic effects of acetaldehyde-biogenic amine condensation products on membrane fluidity, J PHARM PHA, 53(1), 2001, pp. 121-127
Citations number
26
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Pharmacology & Toxicology
Journal title
JOURNAL OF PHARMACY AND PHARMACOLOGY
ISSN journal
0022-3573 → ACNP
Volume
53
Issue
1
Year of publication
2001
Pages
121 - 127
Database
ISI
SICI code
0022-3573(200101)53:1<121:BEOAAC>2.0.ZU;2-G
Abstract
I have studied the effects of four acetaldehyde-biogenic amine condensation products on membrane fluidity of liposomes, consisting of 1-palmitoyl-2-ol eoylphosphatidylcholine and cholesterol, by measuring fluorescence polariza tion using different probes. The condensation products were 1-methyl-1,2,3,4-tetrahydro-beta -carboline (MTBC), 6-hydroxy-1 -methyl-1,2,3,4-tetrahydro-beta -carboline (6-OH-MTBC), 3-carboxy-1-methyl-1,2,3,4-tetrahydro-beta -carboline (3-C-MTBC) and 6,7-d ihydroxy-1-methyl-1,2,3,4-tetrahydroisoquinoline (salsolinol). They changed the fluidity of the hydrophobic and hydrophilic regions of liposomal membr anes at micromolar levels almost corresponding to their antibacterial and a ntiplatelet concentrations, but their membrane effects varied by structure, concentration and membrane lipid composition. MTBC and salsolinol showed b iphasic effects on the inner layers of membranes to enhance the fluidity at 250-1000 muM and reduce the fluidity at 50-100 muM, whereas both of them f luidized the outer layers of the membranes. 3-C-MTBC concentration-dependen tly fluidized both layers of membranes. 6-OH-MTBC most weakly enhanced and reduced the fluidity of the outer and inner layers, respectively. The membr ane effect of MTBC was the greatest of the four condensation products. MTBC (50-1000 nM) significantly reduced the fluidity by exclusively acting on t he membrane core, but was less effective in fluidizing the membrane surface . However, the others were not active at low nanomolar levels. The membrane effects may be partly responsible for the antibacterial and an tiplatelet actions of the acetaldehyde-biogenic amine condensation products , although they do not appear to be simple membrane fluidizers.