Selenium protective effects against Hg toxicity: molecular characterization of naturally involved selenocompounds

• Grant number: 24/15044-8
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Start date: December 15, 2024
• End date: March 07, 2025
• Field of knowledge: Health Sciences - Pharmacy - Toxicological Analysis
• Principal Investigator: Fernando Barbosa Júnior
• Grantee: Fernando Barbosa Júnior
• Visiting researcher: Laurent Ouerdane
• Visiting researcher institution: Université de Pau et des Pays de l'Adour, France
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Mercury pollution, a severe issue globally and particularly in the Brazilian Amazon due to activities like gold mining and deforestation, poses serious health risks to local communities. High Hg exposure levels have been documented in these populations, leading to concerns about neurological impacts and other health effects resembling Minamata disease. Interestingly, despite elevated Hg levels, these communities also exhibit exceptionally high Se levels, primarily from dietary sources like Brazil nuts and fish.The project hypothesizes that Se may mitigate Hg toxicity through complex biochemical interactions yet not fully understood. Previous observations suggest a protective role of Se against Hg toxicity in Amazonian populations, akin to findings in the Inuit community in Canada. This study seeks to characterize Se exposure levels and species in the Amazonian population, including different dietary sources and potential seasonal variations. Special emphasis will be placed on understanding Se metabolites in both human samples and selected fish species consumed locally, considering their position in the aquatic trophic chain.Dr. Ouerdane's role during his visit to USP involves optimizing analytical techniques for Se speciation using advanced LC-MS methods, which will be crucial for identifying and quantifying Se compounds in biological samples. His work will be performed in the frame of the project ANR-FAPESP project, SeMerAMAZON (2024-2028) "Understanding of the mercury-selenium interaction in Amazon riverside populations by combining cutting-edge analytical and toxicological approaches", FAPESP Grant 2022/03476-5. It aims to investigate the interaction between mercury (Hg) and selenium (Se) in Amazon riverside populations, addressing significant environmental and health concerns. His expertise in elemental and molecular mass spectrometry, particularly in characterizing novel selenocompounds, will significantly enhance the project's analytical capabilities. Moreover, his presence will foster scientific exchange and collaboration between CNRS and USP, leveraging his experience in metal/metalloid speciation and analytical chemistry. (AU)