Antioxidant effect of quinoline derivatives containing or not selenium: Relationship with antinociceptive action quinolines are antioxidant and antinociceptive.

The present study investigated the antioxidant effect of a new class of quinoline derivatives (a-d) on assays in vitro. Lipid peroxidation, thiol peroxidase-like and free radical scavenging activities were determined to evaluate antioxidant activity of compounds. Thiol oxidase-like and δ-aminolevulinate dehydratase activities were performed as a toxicological parameter. A second objective of this study was to evaluate the in vivo antinociceptive effect of the compound with better antioxidant effect and without toxic effects in a model of nociception induced by formalin in mice. In liver, at 100 µM, compound a reduced the lipid peroxidation to the control levels, while compounds c and d partially reduced it. In brain, only compound d partially reduced the lipid peroxidation at 50 and 100 µM. Compound b did not have an effect on the lipid peroxidation. Thiol peroxidase-like and free radical scavenging activities are not involved in the antioxidant mechanisms of these compounds. Compounds did not present thiol oxidase-like activity and effect on the δ-aminolevulinate dehydratase. In vivo experiments showed that compound a caused an inhibition of licking time in the first and second phases, and edema formation induced by formalin. In conclusion, quinoline derivative without selenium presented better in vitro antioxidant effect and in vivo antinociceptive activity.