Lutzomyia longipalpis is known as one of the primary insect vectors of visceral leishmaniasis. For such ectothermic organisms, the ambient temperature is a critical life factor. However, the impact of temperature has been ignored in many induced-stress situations of the vector life. Therefore, this study explored the interaction of Lu. longipalpis with temperature by evaluating its behaviour across a thermal gradient, thermographic recordings during blood-feeding on mice, and the gene expression of heat shock proteins (HSP) when insects were exposed to extreme temperature or infected. The results showed that 72 h after blood ingestion, Lu. longipalpis became less active and preferred relatively low temperatures. However, at later stages of blood digestion, females increased their activity and remained at higher temperatures. Real-time imaging showed that the body temperature of females can adjust rapidly to the host and remain constant until the end of blood-feeding. Insects also increased the expression of HSP90(83) during blood-feeding. Our findings suggest that Lu. longipalpis interacts with temperature by using its behaviour to avoid temperature-induced physiological damage during the gonotrophic cycle. However, the expression of certain HSP might be triggered to mitigate thermal stress in situations where a behavioural response is not the best option.
This is the peer reviewed version of the following article: Martins, K.A., Morais, C.S., Broughton, S.J., Lazzari, C.R., Bates, P.A., Pereira, M.H. et al. (2022) Response to thermal and infection stresses in an American vector of visceral leishmaniasis. Medical and Veterinary Entomology, 1– 14. Available from: https://doi.org/10.1111/mve.12626 which has been published in final form at https://resjournals.onlinelibrary.wiley.com/doi/10.1111/mve.12626 This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.