Uric acid oxidation and lipid profile modulation of neutrophils infected with Pseudomonas aeruginosa

• Grant number: 23/05200-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2023
• End date: May 31, 2025
• Field of knowledge: Biological Sciences - Biochemistry - Metabolism and Bioenergetics
• Principal Investigator: Flavia Carla Meotti
• Grantee: Dimitri Peixoto Menezes
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 18/14898-2 - Investigations of the redox processes in inflammatory response and associated pathologies, AP.JP2

Abstract

The production of reactive intermediates in the oxidation of uric acid is an important event during an inflammatory process. These intermediates can oxidize proteins and lipids. Preliminary data from our group appreciated that the oxidant power of uric acid induces an increase in triacylglycerols (TAGs) in neutrophils infected with Pseudomonas aeruginosa, modulating the lipid profile of these cells. Furthermore, we have already demonstrated that oxidation of uric acid by neutrophils decreases the production of hypochlorous acid due to competition between uric acid and chloride for myeloperoxidase. As a consequence there is a decrease in the bactericidal action of neutrophils against Pseudomonas aeruginosa. In this study we investigated the oxidation of uric acid and its effects on the lipid profile in order to trace possible involvement of oxidized lipids and the inflammatory response during an infectious process. Initially we will evaluate the lipidome including oxidized lipids through oxylipidomics analysis of neutrophils from healthy donors and from dHL-60 (neutrophil-like differentiated human promyelocytic leukemia cells) infected with Pseudomonas aeruginosa in the presence and absence of uric acid using method of liquid chromatography coupled to mass spectrometry (LC/MS/MS). The formation of lipid droplets will be monitored by microscopy. In parallel will be evaluated the modulation of the release of pro-inflammatory cytokines Interleukin 1 - Beta,Tumor necrosis factor (TNF-±), IL-6 using ELISA techniques. So, this study will contribute to the understanding of the role of uric acid in the remodeling and oxidation of lipids and the relationship of these processes with signaling, aiming at discovery of new therapeutic targets capable of controlling infection and inflammation.