Increase of complex I and reduction of complex II mitochondrial activity are possible adaptive effects provoked by fluoride exposure

Author(s)

Pereira, Heloisa Aparecida Barbosa Silva ^[1] ; Araujo, Tamara Teodoro ^[1] ; Dionizio, Aline ^[1] ; Trevizol, Juliana Sanches ^[1] ; Pereira, Fabricio Soares ^[1] ; Iano, Flavia Godoy ^[1] ; Ximenes, Valdecir Faria ^[2] ; Buzalaf, Marilia Afonso Rabelo ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Biol Sci, Bauru Dent Sch, Al Octavio Pinheiro Brisolla 9-75, BR-17012901 Sao Paulo - Brazil

^[2] Sao Paulo State Univ UNESP, Dept Chem, Fac Sci, POB 473, BR-1703336 Sao Paulo - Brazil

• Document type: Journal article
• Source: HELIYON; v. 7, n. 1 JAN 2021.
• Web of Science Citations: 0

Abstract

Fluoride (F) can induce changes in the expression of several liver proteins, most of them localized in the mitochondria and its effect is dose- and time-dependent. This study analyzed the effect of distinct F concentrations and exposure periods on the mitochondrial activity of complex I-III and II-III in the liver. Thirty-six 21-day-old male Wistar rats were divided into 2 groups (n =18) according to the duration of the treatment (20 or 60 days). They were subdivided into 3 subgroups (n = 6) according to the concentration of F (0 mg/L, 15 mg/L or 50 mg/L). After the experimental periods, the animals were anesthetized, liver mitochondria were isolated and stored for activity analyses. The determination of complexes II-III and I-III was based on the reduction of cytochrome c(3+) to cytochrome c(2+) performed spectrophotometrically. Bioinformatics analyses were performed using data from a previous study (Pereira et al., 2018). The mitochondrial complex I-III was significantly activated in the groups treated with 50 mgF/L for 20 days and 15 mgF/L for 60 days. The complex II-III was significantly reduced in the group treated with the higher F dose for 60 days. The networks indicated more changes in mitochondrial proteins in the group treated with the higher dose for 20 days; the reduction is probably linked to the activation of the complex I-III. The reduction in the complex II-III upon exposure to the higher F dose in the long term might be part of an adaptative mechanism of the body to counteract the deleterious effects of this ion on the energy metabolism. (AU)

• FAPESP's process: 18/24073-0 - Implantation of an animal model for diabetes of type 2 induced by diet and streptozotocin to investigate the effect of chronic ingestion of fluoride in insulin resistance and expression of hepatic and muscular proteins
• Grantee: Heloisa Aparecida Barbosa da Silva Pereira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral