Effect of 2,2'-dicarbomethoxylamino-5,5'-dibenzimidazolyl ketone on antioxidant defenses of Acanthocheilonema viteae and its laboratory host Mastomys natalensis.

ABSTRACT

The effect of the macrofilaricidal agent of 2,2'-dicarbomethoxylamino-5,5'-dibenzimidazolyl ketone (C.D.R.I. compound 82/437), on the metabolism of reactive oxygen species (ROs) in Acanthocheilonema viteae and Mastomys natalensis was measured following intraperitoneal administration at therapeutic doses. The recovered worms possessed substantially reduced levels of catalase and glutathione peroxidase (GPx), and thus were less able to detoxify H2O2. Nonetheless, the subcutaneous and adjoining muscle tissues, in which the parasites were lodged, exhibited elevated levels of antioxidant enzymes and reduced glutathione. It is concluded that compound 82/437 kills the filariid by paralysing its H2O2 detoxifying capacity without altering ROs metabolism in the tissue in which the parasite resides. Furthermore, since catalase and GPx of the liver and lungs do not show sign of inhibition, a difference appears to exist in the enzymes of the parasite and the host.