Effects of Long-Acting Anticoagulant Rodenticides on Rabbit Plasma Extracellular Vesicles

Environmental toxicants and physiological stressors can significantly impact the production and composition of extracellular vesicles (EVs), which are mediators of long-distance intercellular communication. Understanding these processes is essential since EVs can exert far-reaching effects on diverse tissues and organs, including the central nervous system, by crossing the blood-brain barrier. This study investigated plasma EV dynamics in response to long-acting anticoagulant rodenticides (LAARs), warfarin analogs with long biological half-lives used to eradicate rodent infestation that also present a public health hazard. EVs were isolated from plasma samples collected from adult male New Zealand White rabbits administered a mixture of 3 potent LAARs (brodifacoum, BDF; difenacoum, DFC; and bromadiolone, BDL) using a polymer-based precipitation technique. Nanoparticle tracking analysis (NTA) revealed a time-dependent decrease in EV concentration and changes in size distribution. Cotreatment of rabbits with the bile sequestrant cholestyramine (CSA), which accelerates LAAR clearance from rabbits, reversed some effects of LAARs on the EVs. Mass spectrometric analysis showed that all 3 LAARs are associated with isolated EVs and that those levels were reduced by CSA. Application of EVs from LAAR-treated rabbits induced microglial cell death. Collectively, our findings suggest that LAARs can influence both the concentration and size distribution of circulating EVs, which in turn may facilitate the transport of LAARs throughout the body where they can have toxic effects.