Effects Of Single And Joint Exposure Of Atrazine And Chlorpyrifos On Autophagy In The Brain Of Common Carp

The triazine herbicide atrazine and the organophosphorus insecticide chlorpyrifos arefrequently and extensively applied in agriculture by runoff and leaching, which could contaminatethe aquatic system and effect aquatic organisms, especially fish. Autophagy is a normalphysiological process, which degrade the intracellular substance of cell, and have became adeveloping research focus, involved the fields of biology, medicine, botany and microbiology. Inthis study, coding sequences of LC3and dynein were cloned and the polyclonal antibody has beensuccessfully prepared by the methods of molecular biology. As the experimental animals, this studyinvestigated effects of sub-chronic exposure of atrazine (4.28,42.8and428μg/L), chlorpyrifos(1.16,11.6and116μg/L) and their mixture (1.13,11.3and113μg/L) on antioxidant function andautophagy-related gene (LC3, dynein and TOR) expression in the brain of common carp. Theresults showed that:1. Fusion proteins of LC3and dynein were expressed in prokaryotic system in this study. Thepolyclonal antibodies were prepared and antibody titer was about1:12800in New Zealand whiterabbit.2. Single and combined exposure of atrazine and chlorpyrifos could induce oxidative stressand reduce the activities of superoxide radical scavenging and hydroxyl radical scavenging,resulting in the destruction of antioxidant function.3. Single and combined exposure of atrazine and chlorpyrifos could up-regulate iNOSexpression increase iNOS activity and production of NO. The results demonstrated that single andcombined exposure of atrazine and chlorpyrifos could induce the production of NO and causetissue oxidative damage.4. Single and combined exposure of atrazine and chlorpyrifos could reduce the mRNA andprotein expression of LC3and dynein, and increase the mRNA expression of TOR. In the recoveryperiod, the mRNA and protein expression of LC3and dynein was decreased and the mRNAexpression of TOR was increased. The results show that autophagy was inhibited in the exposureperiod and activated in the recovery period.In summary, antioxidant function was decreased, the content of free radicals were increased,the mRNA and protein expression of LC3and dynein were decreased and the mRNA expression ofTOR was increased after single and combined sub-chronic exposure of atrazine and chlorpyrifos,thereby autophagy was inhibited, insulting in the damage of the brain of common carp. The results provide the basis for the rich of atrazine and chlorpyrifos toxicology data.