Bee venom, also known as apitoxin, is produced by honey bees (Apis mellifera) and comprises a complex mixture of substances with reported therapeutics and pharmacological properties. However, this natural product can cause severe allergic reactions, and further toxicological studies on animal models are necessary to ensure safe use. Bee venom obtained from Apis mellifera and collected in Northeast Brazil was used to investigate its effects in normal and breast cancer cells and the nematode Caenorhabditis elegans. In the present study, we employed the acute exposure assay system of C. elegans to evaluate bee venom's toxicity in vivo. Synchronized L4 larval stage worms (N2-Bristol) were exposed for three hours in M9 buffer to bee venom. Behavioral parameters, including reproduction, survival, DAF-16 transcription factor location (zIs356 [
daf-16p::
daf-16a/b::GFP +
rol-6(
su1006)]), and superoxide dismutase-3 (SOD-3; muIs84 [(pAD76)
sod-3p::GFP +
rol-6(
su1006)]) expression, were analyzed. Bee venom cytotoxic impacts on MDA-MB-231 and J774 A.1 cells were evaluated by the MTT assay until 72 hours of exposure. Acute exposure to bee venom resulted in a decrease in C. elegans survival, feeding behavior (p<0.0001), movement (p<0.0001) while induced an increase in the gaps between the cycles of defecation (p<0.001). Bee venom has also decreased nematode reproduction by reducing both egg-production (p<0.0001) and egg-laying (p<0.05). This toxin enhanced DAF-16 translocation from the cytoplasm to the nucleus, which did not affect the SOD-3 expression. Bee venom significantly inhibited the proliferation of MDA-MB-231 cells and caused a cytotoxic effect on macrophages. Our results show that exposure to bee venom produced significant toxic effects on the cells and animal model studied. C. elegans can provide information about the molecular and cellular mechanisms of bee venom toxicity and serve as a model organism to study the toxic effects of this natural product on human health.