Nuclear Lipid droplets in Oenocytes cells from Triatoma infestans insects are a dynamic nuclear organoid

GIROTTI, JUAN R; BORÚS DELFINA L; FAVALE NICOLÁS O; VES LOSADA ANA

Mendoza

Congreso; LVIII Reunión Anual de SAIB; 2022

SAIB

The objective of the work was to characterize nuclear populations of Lipid Droplets (nLD) in Triatoma infestans (vinchuca) under different development conditions. This hematophage insect is one of the main vectors of the parasite Trypanosoma cruzi, the causative agent of Chagas disease in Argentina and the Americas. The cuticle (C) is the insect most external structure, which protects against physical, chemical (dehydration, etc.) and biological (infections, etc.) external factors. Oenocyte cells (OE) are involved in the anabolism of C hydrophobic molecules (hydrocarbons, alcohols, waxes, glycerides, fatty acids, etc). The fat body (FB) is the organ that regulates the entire insect metabolism. The information on the lipid metabolism of the insect will allow the acquisition of new tools to control the vector. Taking into account the scarce information on OE from C in Triatoma infestans, the aim of the work was to characterized the LD populations in these cells as organoids involved in the genesis of Previously, we demonstrated that in liver, LD populations are dynamic organelle where neutral lipids are stored, mainly located in the cytosol (cLD) and in a small proportion in the nucleus (nLD). For this purpose, protocols were developed and optimized to identify and characterize LD populations in the different cells beneath the cuticle (C). We examined and characterized the LD populations of OE cells from fifth instar nymphs of the insect that were feed or starved for 1 month. Light field microscopy and fluorescence (epifluorescence and confocal) and hematoxylin / Oil Red and DAPY / BODIPY stains were used, respectively. In OE cells the main LD population is located in the cytosol and a small population within the cell nucleus (nLD) in both conditions, feed and starved insects. These results would confirm the role assigned to OE to actively participate in the anabolism of the cuticle components. In conclusion, Triatoma infestans cuticular oenocytes were characterized as cells that have a very varied morphology, depending on the development state of the insect, and are larger than the surrounding epithelial cells. The OEs have two LD populations in both conditions tested, a main cytosolic and a nuclear one. These are the first results where nLDs are described in insects.