title: Programmed Cell Death in the Honey Bee (Apis mellifera) (Hymenoptera: Apidae) Worker Brain Induced by Imidacloprid.
abstract: Honey bees are at an unavoidable risk of exposure to neonicotinoid pesticides, which are used worldwide. Compared with the well-studied roles of these pesticides in nontarget site (including midgut, ovary, or salivary glands), little has been reported in the target sites, the brain. In the current study, laboratory-reared adult worker honey bees (Apis mellifera L.) were treated with sublethal doses of imidacloprid. Neuronal apoptosis was detected using the TUNEL technique for DNA labeling. We observed significantly increased apoptotic markers in dose- and time-dependent manners in brains of bees exposed to imidacloprid. Neuronal activated caspase-3 and mRNA levels of caspase-1, as detected by immunofluorescence and real-time quantitative PCR, respectively, were significantly increased, suggesting that sublethal doses of imidacloprid may induce the caspase-dependent apoptotic pathway. Additionally, the overlap of apoptosis and autophagy in neurons was confirmed by transmission electron microscopy. It further suggests that a relationship exists between neurotoxicity and behavioral changes induced by sublethal doses of imidacloprid, and that there is a need to determine reasonable limits for imidacloprid application in the field to protect pollinators.
authors.affiliation: Department of Bee Protection and Biological Safety, Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Wu
authors.affiliation: Department of Bee Protection and Biological Safety, Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China. ztapis@263.net.
authors.forename: Ting
authors.initials: T
authors.lastname: Zhou
authors.affiliation: Department of Bee Protection and Biological Safety, Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Bee Protection and Biological Safety, Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
authors.forename: Ping-Li
authors.initials: PL
authors.lastname: Dai
authors.affiliation: Department of Bee Protection and Biological Safety, Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
authors.forename: Shu-Fa
authors.initials: SF
authors.lastname: Xu
authors.affiliation: Department of Bee Protection and Biological Safety, Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
authors.forename: Hui-Ru
authors.initials: HR
authors.lastname: Jia
authors.affiliation: General Affairs Office, Beijing Management Station of Apiculture and Sericulture, Beijing 100029, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy; D001516:Bees / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D001921:Brain / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D020170:Caspase 1 / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D007093:Imidazoles / Q000633:toxicity*; D020287:In Situ Nick-End Labeling; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D007306:Insecticides / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D000073943:Neonicotinoids; D009474:Neurons / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D009574:Nitro Compounds / Q000633:toxicity*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D007093:Imidazoles; D019476:Insect Proteins; D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D012333:RNA, Messenger; C082359:imidacloprid; D020170:Caspase 1
keywords: apoptosis; autophagy; brain of honey bee; caspases; imidacloprid