Effects of organophosphorus and pyrethroid pesticides on antioxidant enzymes and reactivation effects of Pralidoxime : in vitro studies

Abstract EN

The present study aimed to assess the inhibition effects of organophosphate pesticides, malathionR, dichlorvosR; pyrethroid pesticides, deltamethrinR, λ-cyhaloethrinR on antioxidant enzymes and the reactivation ability of pralidoxime against pesticide inhibited-antioxidant enzymes.

Oximes were reported by reactivation ability against organophosphate inhibitedacetylcholinesterase and we focused to investigate the reactivation effect of pralidoxime against organophosphate inhibited–antioxidant enzymes.

IC50 values were determined by means of activity percentage diagrams.

The concentrations of deltamethrinR, malathionR, dichlorvosR, λcyhaloethrinR that inhibited 50% of catalase were 5.2 µM, 158 µM, 133 µM, 320 µM, respectively, inhibited 50% of superoxide dismutase were 62 µM, 240 µM, 328 µM, 2320 µM, respectively and inhibited 50% of glutathione peroxidase were 0.7 µM, 1198 µM, 1638 µM, 98 µM, respectively.

All pesticide doses showed an inhibition effect on antioxidant enzymes.

DeltamethrinR was found to be a more potent inhibitor for the antioxidant enzymes followed by the rest of the pesticides used in this study.

The reactivation effect of pralidoxime was determined for organophosphate inhibited-enzymes.

Reactivation results showed that only catalase is reactivated by pralidoxime against dichlorvosR and malathionR.

Under the exposure of 50-800 µM malathionR concentrations, the activities of catalase were calculated as 72-11%, respectively.

After, inhibited catalase was incubated with 1 mM and 10 mM pralidoxime, the activities of catalase were calculated as 92-31% and 98-39%, respectively.

Under the exposure of 100-1500 µM dichlorvosR concentrations, the activities of catalase were calculated as 50- 6%, respectively.

After, inhibited catalase was incubated with 1 mM and 10 mM pralidoxime, the activities of catalase were calculated as 95-30% and 93-28%, respectively.

When the results are examined, it is seen that increasing the pralidoxime concentration does not significantly affect the reactivation percentage of the catalase enzyme.