The photosensitizing properties of Fenbufen, gamma-oxo-[1,1'-biphenyl]-4-butanoic acid, have been studied in vitro following the lysis of the erythrocytes and the peroxidation of unilamellar phosphatidylcholine liposomes in phosphate buffer suspensions, irradiated with UVA light in the presence of the drug. The results show that the phototoxic activity of the drug is negligible under nitrogen, and increases with increasing oxygen concentration in the medium. The investigation of the drug photolysis showed that formation of photoproducts, which have been isolated and characterized, is negligible within the irradiation times of the sensitization experiments. The effect of suitable additives such as mannitol, reduced glutathione, superoxide dismutase and some metal ions suggests the participation of free radicals in the photosensitization. The presence of a photodynamic pathway with the involvement of singlet oxygen was evidenced by the addition of sodium azide in phosphate-buffered solutions enriched in deuterium oxide. RI Sortino, Salvatore/E-4684-2011
Molecular mechanism of drug photosensitization .10. Membrane photodamage sensitized by fenbufen
DE GUIDI, Guido;SORTINO, Salvatore;
1996-01-01
Abstract
The photosensitizing properties of Fenbufen, gamma-oxo-[1,1'-biphenyl]-4-butanoic acid, have been studied in vitro following the lysis of the erythrocytes and the peroxidation of unilamellar phosphatidylcholine liposomes in phosphate buffer suspensions, irradiated with UVA light in the presence of the drug. The results show that the phototoxic activity of the drug is negligible under nitrogen, and increases with increasing oxygen concentration in the medium. The investigation of the drug photolysis showed that formation of photoproducts, which have been isolated and characterized, is negligible within the irradiation times of the sensitization experiments. The effect of suitable additives such as mannitol, reduced glutathione, superoxide dismutase and some metal ions suggests the participation of free radicals in the photosensitization. The presence of a photodynamic pathway with the involvement of singlet oxygen was evidenced by the addition of sodium azide in phosphate-buffered solutions enriched in deuterium oxide. RI Sortino, Salvatore/E-4684-2011I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
