Effects of botulinum toxin type a on nucleotide binding oligomerization domain-like receptor 3 inflammasome in trigeminal ganglion of a rat migraine model.

[BACKGROUND] Botulinum toxin type A (BTX-A) has been used in the prevention and treatment of chronic migraine, but the detailed mechanism was not clear completely.

[OBJECTIVE] The effects of BTX-A on nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome and interleukin-1 beta (IL-1β) were explored in the trigeminal ganglion of migraine model rats.

[METHODS] Healthy adult male Sprague-Dawley (SD) rats were randomly divided into groups. Von Frey fiber filaments were used to detect the periorbital pain area of rats. The immunoblotting and Immunofluorescence were used to detect the expression of NLRP3 inflammasome and IL-1β in the trigeminal ganglia of rats.

[RESULTS] The periorbital pain area of rats in the migraine model group was significantly lower than that of the Sham group, and the difference was statistically significant (p < 0.05). Compared with the Sham group, the expressions of NLRP3, pro-caspase-1, caspase-1 and mature IL-1β in the migraine model group were significantly increased, and the difference was statistically significant (p < 0.05). Compared with the IA control group, the expressions of NLRP3, pro-caspase-1, caspase-1 and mature IL-1β in 5 U/kg BTX and 10 U/kg BTX-A group were significantly reduced (p < 0.05).

[CONCLUSION] BTX-A inhibits the synthesis of NLRP3 inflammasome and mature IL-1β in the trigeminal ganglion from rat migraine models. Its inhibitory effect on the inflammation of the primary nociceptive neurons of the trigeminal nerve may be one of its important mechanisms for the prevention of migraine.