Biotransformation of inorganic arsenic (As-i) in Nile Tilapia (Oreochromis niloticus) and evaluation of its antagonism in the presence of selenium

• Grant number: 18/25002-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2019
• End date: June 30, 2023
• Field of knowledge: Health Sciences - Pharmacy - Toxicological Analysis
• Principal Investigator: Mario Henrique Gonzalez
• Grantee: Nathalia dos Santos Ferreira
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil

Abstract

Mostly, the total determination of an element is not sufficient to provide information about its toxicity, bioavailability and biochemical function, being necessary studies of fractionation and chemical speciation to complement the information. The determination of arsenic in fish is of great analytical interest due to its toxicity, since its effects are closely related to its chemical forms and their oxidation states, being the inorganic forms As (III) and (V) more toxic than organic forms. This research project has the objective of investigating the biotransformation of inorganic arsenic in Nile Tilapia (Oreochromis niloticus) and the evaluation of arsenic species distribution: As (III), As (V), MMA (monomethylarsonic acid), DMA (dimethylarsinic acid) and AsB (arsenobetaine) in the livers, stomach, gills and filets by high performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The evaluation of enzymatic activities involved in the mechanisms of antioxidant defense and biotransformation processes of As, with analysis of glutathione (GSH), glutathione peroxidase (GPx) and glutathione S-transferase (GST) are also investigated. Finally, new toxicokinetic parameters will be determined to evaluate the interactions and the antagonistic effects of selenium in arsenic bioaccumulation processes in Nile Tilapia. (AU)