The role of fine particulate matter in inducing toxic responses: from oxidative potential to kidney disease

• Grant number: 22/13888-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: March 01, 2023
• End date: February 29, 2024
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Meteorology
• Principal Investigator: Maria de Fátima Andrade
• Grantee: Caroline Fernanda Hei Wikuats
• Supervisor: Alessandra Tammaro
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of Amsterdam (UvA), Netherlands
• Associated to the scholarship: 20/07674-0 - Toxicity of particulate matter with the evaluation of oxidative potential and its effect on premature renal aging in the Metropolitan Area of São Paulo, BP.DR

Abstract

Particulate matter (PM) presents numerous physical and chemical properties, such as chemical composition, size, and surface area, that may induce various adverse effects on human health. Fine particulate matter (PM2.5) can oxidize target molecules triggering oxidative stress and systemic inflammation through modulation of epigenetic and metabolic processes, which are suspected to be involved in premature renal ageing. Nevertheless, studies involving PM2.5 exposure and renal outcomes are still scarce. The oxidative potential (OP) measures the biological responses caused by exposure to this pollutant (e.g., oxidative stress) and is one of the mechanisms to define the PM components responsible for health effects. Therefore, the main objective of this project is to evaluate the OP of PM2.5 collected during the long-term sampling campaign (2021 and 2022) at the University of São Paulo Medical School (FMUSP). The OP will be determined using two different methods: the dithiothreitol (DTT) and the electron spin resonance (ESR) assays to consider distinct mechanisms of reactive oxygen species (ROS) generation from particles. The analyses will be divided into three periods according to the exposure experiments with mice also carried out at the FMUSP: pre-exposure (from May to October 2021), summer exposure (from November 2021 to April 2022), and winter exposure (from May to October 2022). Statistical significance among the different periods and assays considered for the study will be assessed using nonparametric Mann-Whitney tests. The relationship between the OP results and PM2.5 concentrations will be evaluated with nonparametric Spearman's rank correlations. Furthermore, we plan to explore the relationship between chemical composition and sources of PM2.5 and the OP with multiple linear regression analyses. We also aim to contribute to investigating renal outcomes caused by exposure to PM2.5 in collaboration with the PM-KIDNEY project (FAPESP Thematic Project No. 2019/19433-0). After the research internship, we intend to implement the OP methodology in São Paulo as a technology exchange between the Netherlands and Brazil. (AU)