title: Fluorescence study on rat epithelial cells and liposomes exposed to aromatic nitroxides.
abstract: This study was performed to evaluate the effects, if any, of aromatic nitroxides, namely, indolinic nitroxides, on membrane fluidity of rat epithelial cells using steady-state fluorescence. These nitroxides are being increasingly considered as new and versatile compounds to reduce oxidative stress in biological systems. Hence, the results obtained in this study will give more insights on the interaction of these compounds with biological structures which at present is lacking, especially in view of their possible application as antioxidant therapeutic agents. The probes DPH and Laurdan which give information on the hydrophobic and hydrophilic-hydrophobic regions of the membrane bilayer, respectively, showed that nitroxide 1 (1,2-dihydro-2-methyl-3H-indole-3-one-1-oxyl) significantly increases membrane fluidity, whereas the corresponding phenylimino nitroxide derivative 2 (1,2-dihydro-2-methyl-3H-indole-3-phenylimino-1-oxyl) leads to membrane rigidification. The aliphatic nitroxide TEMPO included in this study for comparison produced no modifications. Consequently, it appears that the structure of the heterocyclic rings (aromatic or aliphatic) and the substituents may affect membrane fluidity differently.
authors.affiliation: Dipartimento di Biologia M.C.A., Università di Camerino, Via Camerini, 2, 62032 Camerino, Italy. rosita.gabbianelli@unicam.it
authors.forename: Rosita
authors.initials: R
authors.lastname: Gabbianelli
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Falcioni
authors.forename: Giulio
authors.initials: G
authors.lastname: Lupidi
authors.forename: Lucedio
authors.initials: L
authors.lastname: Greci
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Damiani
mesh_terms: D000818:Animals; D003497:Cyclic N-Oxides / Q000737:chemistry / Q000494:pharmacology*; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects*; D005260:Female; D005454:Fluorescence Polarization; D007211:Indoles / Q000737:chemistry / Q000494:pharmacology*; D008081:Liposomes / Q000378:metabolism*; D008297:Male; D008560:Membrane Fluidity / Q000187:drug effects; D015394:Molecular Structure; D051381:Rats; D017208:Rats, Wistar
chemical_list: C496194:1,2-dihydro-2-methyl-3H-indole-3-one-1-oxyl; C496193:1,2-dihydro-2-methyl-3H-indole-3-phenylimino-1-oxyl; D003497:Cyclic N-Oxides; D007211:Indoles; D008081:Liposomes