Abstract
This study was conducted to investigate the oxidative stress and apoptotic signs detectable by flow cytometry as proposed pathogenicity mechanisms for the mosquitocidal bacterium Bacillus,thuringiensis (Bt) in the mosquito vector, Culex pipiens. Obtained data showed elevation in the levels of the oxidative stress biomarkers, the lipid peroxidation and protein oxidation, upon Bt-infection. Larvae showed significant higher levels of both lipid peroxidation and protein oxidation at 12 and 24h post-infection compared to control ones. In addition, Bt-inoculated adult mosquitoes also showed significant higher lipid peroxidation at 12 and 24h post-inoculation compared to control ones. These signs of oxidative stress were more pronounced in bacterial infected larvae than in bacterial inoculated adult mosquitoes. Finally, Bt-infected larvae showed significant higher percentages of cellular apoptosis at 12 an 24h post-infection compared to control ones. These data may indicate that Bt infection induced oxidative stress and apoptosis proceeding cellular damage, and thus, may be suggested as important pathogenicity mechanisms of Bt in its mosquito host. And hence, these data may participate in improving our understanding of the mosquito-Bt interaction scenario, which may help improving the biocontrol measurements against mosquito vectors.