The lionfish (Pterois volitans) is a venomous invasive species found in the Caribbean and Northwestern Atlantic. It poses a growing health problem due to the increase in frequency of painful stings, for which no treatment or antidote exists, and the long-term disability caused by the pain. Understanding the venom’s algogenic properties can help identifying better treatment for these envenomations. In this study, we provide the first characterization of the pain and inflammation caused by lionfish venom and examine the mechanisms through which it causes pain using a combination of in vivo and in vitro approaches including behavioral, physiological, calcium imaging and electrophysiological testing. Intraplantar injections of the venom produce a significant increase in pain behavior, as well as a marked increase in mechanical sensitivity for up to 24 hours after injection. The algogenic substance(s) are heat-labile peptides that cause neurogenic inflammation at the site of injection and induction of Fos and microglia activation in the superficial layers of the dorsal horn. Finally, calcium imaging and electrophysiology experiments show that the venom acts predominantly on non-peptidergic, TRPV1-negative, nociceptors, a subset of neurons implicated in sensing mechanical pain. These data provide the first characterization of the pain and inflammation caused by lionfish venom, as well as the first insight into its possible cellular mechanism of action.
1 Department of Physiology and Cell Information Systems, McGill University, Montreal QC, Canada.
2 Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON, Canada. Department of Physiology and the Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada
3 Alan Edwards Center for Research in Pain, McGill University. 740 Dr. Penfield Avenue, suite 3100. Montreal, Quebec, H3A0G1, Canada.
Correspondence: Dr. Reza Sharif-Naeini, Department of Physiology & Cell Information Systems Group, McGill University, Life Sciences Complex (Bellini), suite 171, 3649 Promenade Sir William Osler, Montréal, Québec H3G 0B1, Phone: 514-398-5361, Reza.firstname.lastname@example.org
Conflict of Interest: There is no conflict of interest