Chronic pollution in aquatic ecosystems can lead to many adverse effects,including a greater susceptibility to pathogens among resident biota.Trifloxystrobin(TFS)is a strobilurin fungicide widely used in Asia to contr...Chronic pollution in aquatic ecosystems can lead to many adverse effects,including a greater susceptibility to pathogens among resident biota.Trifloxystrobin(TFS)is a strobilurin fungicide widely used in Asia to control soybean rust.However,it has the potential to enter aquatic ecosystems,where it may impair fish resistance to viral infections.To explore the potential environmental risks of TFS,we characterized the antiviral capacities of fish chronically exposed to TFS and subsequently infected with spring viraemia of carp virus(SVCV).Although TFS exhibited no significant cytotoxicity at the tested environmental concentrations during viral challenge,SVCV replication increased significantly in a time-dependent manner within epithelioma papulosum cyprini(EPC)cells and zebrafish exposed to 25μg/L TFS.Results showed that the highest viral load was more than 100-fold that of the controls.Intracellular biochemical assays indicated that autophagy was induced by TFS,and associated changes included an increase in autophagosomes,conversion of LC3-II,accumulation of Beclin-1,and degradation of P62 in EPC cells and zebrafish.In addition,TFS markedly decreased the expression and phosphorylation of mTOR,indicating that activation of TFS may be associated with the mTORmediated autophagy pathway.This study provides new insights into the mechanism of the immunosuppressive effects of TFS on non-target aquatic hosts and suggests that the existence of TFS in aquatic environments may contribute to outbreaks of viral diseases.展开更多
基金This work was supported by the National Natural Science Foundation of China(31902410)Program of State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products(KF20200106)+1 种基金Natural Science Foundation of Zhejiang Province(LY21C190002)Foundation of Ningbo City of China(202003N4120)。
文摘Chronic pollution in aquatic ecosystems can lead to many adverse effects,including a greater susceptibility to pathogens among resident biota.Trifloxystrobin(TFS)is a strobilurin fungicide widely used in Asia to control soybean rust.However,it has the potential to enter aquatic ecosystems,where it may impair fish resistance to viral infections.To explore the potential environmental risks of TFS,we characterized the antiviral capacities of fish chronically exposed to TFS and subsequently infected with spring viraemia of carp virus(SVCV).Although TFS exhibited no significant cytotoxicity at the tested environmental concentrations during viral challenge,SVCV replication increased significantly in a time-dependent manner within epithelioma papulosum cyprini(EPC)cells and zebrafish exposed to 25μg/L TFS.Results showed that the highest viral load was more than 100-fold that of the controls.Intracellular biochemical assays indicated that autophagy was induced by TFS,and associated changes included an increase in autophagosomes,conversion of LC3-II,accumulation of Beclin-1,and degradation of P62 in EPC cells and zebrafish.In addition,TFS markedly decreased the expression and phosphorylation of mTOR,indicating that activation of TFS may be associated with the mTORmediated autophagy pathway.This study provides new insights into the mechanism of the immunosuppressive effects of TFS on non-target aquatic hosts and suggests that the existence of TFS in aquatic environments may contribute to outbreaks of viral diseases.
