Periodic Reporting for period 2 - SENSO-CIGUA (Neurobiology of sensory disturbances induced by ciguatoxins)
Période du rapport: 2022-09-01 au 2023-08-31
There is no specific or effective treatment for ciguatera sensory disturbances. They greatly affect the quality of life, especially when they last for weeks, months or even years, associated with chronic fatigue. In areas endemic for ciguatera, the dietary eviction and marketing ban of the most incriminated seafood species make ciguatera a significant public health and economic concern.
The overall objective of the SENSO-CIGUA project is to better understand the neural mechanisms by which ciguatoxins induce these sensory disturbances in order to ultimately find out bases for specific treatment(s).
In conclusion of the action, the project, which achieved most of its specific objectives, contributed to a significant advance in the state of the art in the field. Using an assay capable of distinguishing between itch and pain-related behaviours, we characterized the behaviours induced by a range of (sub)nanomolar doses of ciguatoxin administered in direct contact with sensory nerves, and studied the involvement of molecular actors. The project also expanded the available knowledge about the subpopulations of sensory neurons activated by ciguatoxin and its ability to sensitize sensory pathways, for example involved in pain and itch.
We also sought to identify subpopulations of sensory neurons targeted by ciguatoxin, whose better understanding could contribute to increasing knowledge of the neural mechanisms of ciguatera and beyond, abnormal cold-induced pain and itch.
We also investigated in mice and sensory neurons the ability of ciguatoxin to sensitize (i.e. to increase responses or decrease response thresholds of) receptors and ion channels involved in pain and itch.
Results of the project have been presented at the following international/national conferences or congresses:
• Annual conference of the research network Phycotox 2023, Nantes, France
• Congrès Annuel de Recherche Dermatologique CARD 2023, Brest, France
• International Congress on Neuropathic Pain of IASP Neuropathic Pain Special Interest Group (NeuPSIG) 2023, Lisbon, Portugal
• 12th World Congress on Itch 2023, Miami, United States of America
• American Romanian Academy of Arts and Sciences 2023 (44th ARA Congress), Timisoara, Romania
• 19th Symposium of the French Pain Research Network 2024, Nice, France