Does the administration of pilocarpine prior to venom milking influence the composition of Micrurus corallinus venom?

Abstract

Considering that the scarcity of venom represents a huge challenge for biochemical and functional studies of Micrurus species (coral snakes), in this report we describe for the first time the influence of pilocarpine administration prior to venom milking on the yield and protein composition of Micrurus corallinus venom. The administration of pilocarpine resulted in an increase of about 127% in the volume of venom milked, with similar protein content. Venoms showed similar protein bands distribution and intensity by SDS-PAGE and equivalents RP-HPLC profiles. Our proteomic analysis showed that venoms milked in the presence and absence of pilocarpine presented comparable protein profiles, in terms of protein composition and relative abundance. The toxins identified were assigned to 13 protein families and represent the most complete M. corallinus venom proteome described so far, in terms of number of protein families identified. Our data indicate that the administration of pilocarpine prior to venom milking increases the venom yield and does not change significantly the venom composition of M. corallinus. The employment of pilocarpine represents a useful approach to increase the yield of venom not only for Micrurus species, but also for other genera of snakes with limitations regarding the amount of venom available. SignificanceIn this report, we evaluated the influence of pilocarpine administration prior to venom milking in the overall composition of M. corallinus venom. We showed that the use of pilocarpine 10min before M. corallinus venom milking increases venom yield by ~127%. Not only the volume of venom obtained is higher, but also the protein concentration of both venoms is similar, opposing the idea that a more diluted venom is obtained as a result of pilocarpine administration, observed in non-front-fanged snakes. Shotgun proteomics analysis revealed that venom milked with and without the use of this drug showed similar overall protein composition and relative abundances. In addition, our proteomic approach allowed the identification of 13 toxin families in M. corallinus venom, representing the most complete M. corallinus venom proteome described so far. Moreover, two of these toxin families were identified for the first time in the venom of this species. Thus, considering the scarcity of Micrurus venom for biochemical and functional studies, we highlighted the usefulness of pilocarpine administration prior to venom milking to increase the venom yield of these snakes.