Effect of Fluoride on the Proteomic and Metabolic Profile of the Pancreas in Diabetes-Related Parameters in NOD Mice

• Grant number: 25/01732-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2025
• End date: March 31, 2026
• Field of knowledge: Health Sciences - Dentistry - Social and Preventive Dentistry
• Principal Investigator: Talita Mendes Oliveira Ventura
• Grantee: Maria Fernanda Fernandes Martins
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

The fluoridation of water is an important public health measure for controlling dental caries. Animal studies conducted by our research group have demonstrated that low doses of fluoride (F) in drinking water, similar to those found in public water supplies, increase insulin sensitivity and reduce blood glucose levels in diabetic rodents. Recently, we observed that Non Obese Diabetic (NOD) mice exposed to low doses of F show a decrease in the expression of phosphoenolpyruvate carboxykinase (PEPCK) in the liver. That took us to propose that the reduction in PEPCK, a positive regulator of gluconeogenesis, contributes to increased glucose uptake, which could be a likely mechanism explaining the antidiabetic effects of low doses of F. In this context, since the pancreas is responsible for insulin production, it plays a central role in glucose regulation, and thus, the evaluation of its alterations becomes crucial to elucidate the underlying mechanisms of F effect on glucose metabolism. Therefore, the objective of the present study will be to evaluate the effect of F on the proteomic and metabolomic profiles of the pancreas in NOD mice. In order to achieve this, in vivo models were employed to explore the relationship between exposure to low levels of F, nuclear enolase, and cytoplasmic PEPCK. Thus, 120 mice were divided into 4 groups, according to the treatment to be administered daily by oral gavage (100 ¿L), as follows: 1. Saliva containing 1% DMSO (negative control); 2. 100 ¿g F (as NaF) in saline containing 1% DMSO; 3. ENOblock: 8 ¿g/kg body weight in saline containing 1% DMSO (positive control); 4. Insulin (1 unit) via intradermal injection after confirmation of diabetes, and gavage with saline containing 1% DMSO. The collected pancreases will be processed and prepared for proteomic and metabolomic analysis by nanoLC-ESI-MS/MS. Pancreatic protein identification will be performed using the ion counting algorithm integrated into the software, with a search in the Mus musculus UniProtKB database. The differential expression between groups will be obtained using Progenesis software and analyzed by t-test (p < 0.05). For metabolomics, the generated data will be analyzed using Progenesis QI software. Metabolites of interest will be selected based on ANOVA p-value < 0.05 and fold change > 2. Therefore, the results to be obtained are of great relevance for public health, as water fluoridation, in addition to controlling dental caries, may also play an important role in diabetes therapy.