Acetamiprid mediates cognitive dysfunction through the gut-brain axis: Synaptic damage and immune-mediated blood-brain barrier dysfunction.

Acetamiprid is a widely used neonicotinoid pesticide that can increase the risk of inducing nervous system diseases. Considering the increased exposure to acetamiprid and its impact on cognitive function, further clarification is needed. Therefore, we used a mouse model of drinking water to evaluate the effects of acetamiprid on cognitive dysfunction and the possible underlying mechanisms. Our study revealed that acetamiprid can cause damage to hippocampal and synaptic structures, which in turn leads to a decline in spatial learning and memory abilities in mice. Importantly, acetamiprid exposure altered the composition and diversity of the intestinal flora and induced a systemic immune response in the gutbrain axis. Specifically, acetamiprid exposure damages the gutbrain axis, including structural disorders of the intestinal flora, related neurotransmitters and systemic immune factors. In addition, fecal microbiota transplantation restored the homeostasis of the gut microbiota and reduced the degree of damage to synaptic and spatial learning and memory. Moreover, intestinal barrier function is restored, effectively preventing the entry of harmful substances into intestinal tissue and thereby reducing damage to the bloodbrain barrier and the immune response in the gutbrain. This study provides new insights into potential new mechanisms of acetamidine exposure related to cognitive function.