Combined transcriptome and metabolite profiling analyses provide insights into the chronic toxicity of carbaryl and acetamiprid to Apis mellifera larvae

Despite many studies have revealed that developing honey bee (Apis mellifera) larvae are posting a high risk on exposure to insecticides, the toxicology information on bee larvae remain limited. The present study demonstrated the first assessment of the effects of no observed adverse effect concentration (NOAEC) of carbaryl (CR) and acetamiprid (ACE) on transcriptome and metabolome in honeybee larvae reared in vitro. Chronic exposure to carbaryl caused transcriptional disorders associated with oxidative stress. In addition, a series of metabolic homeostasis were disrupted by carbaryl stress, such amino acid metabolism, purine and pyrimidine metabolism and flavone and flavonol biosynthesis. The activities of enzymic biomarkers including GST, P450, CAT, AChE and SOD were not influenced by ACE stress, while the CR exposure slightly decreased the activity of CAT and SOD. Our results clearly show that ACE and CR display different potential to modulate transcriptome and metabolome associated with their different toxicity against bee larvae.