Salivary metabolome in pregnant women with different stages of periodontitis: an analysis by proton nuclear magnetic resonance (1H-NMR) spectroscopy

• Grant number: 25/11922-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Health Sciences - Dentistry - Pediatric Dentistry
• Principal Investigator: Gerson Aparecido Foratori Junior
• Grantee: Yasmim Zinezi
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

This project aims to characterize the metabolomic profile of unstimulated saliva from pregnant women classified at different stages of periodontitis, according to the criteria of the 2017 World Workshop, using Proton Nuclear Magnetic Resonance (¹H-NMR) spectroscopy. The sample is being consecutively recruited from Public Primary Health Units in the city of Bauru-SP, and will be composed of five groups, defined based on the clinical stage of periodontitis: stage I (G1 = 15), stage II (G2 = 15), stage III (G3 = 15), stage IV (G4 = 15), and control group without periodontitis (G5 = 15). Contextual (such as age, socioeconomic status) and behavioral (daily frequency of toothbrushing and flossing) information will be collected, in addition to clinical periodontal parameters after a full-mouth periodontal examination (probing depth, clinical attachment loss, bleeding on probing, and presence of visible biofilm). Unstimulated saliva samples will be collected and individually analyzed by ¹H-NMR, with subsequent identification and quantification of metabolites. Statistical analysis of quantitative variables will be preceded by normality and homogeneity tests. Variables with normal distribution and homoscedasticity will be compared between groups by ANOVA (with Tukey's post-hoc); quantitative variables without normal distribution and ordinal qualitative variables will be analyzed by Kruskal-Wallis (with Dunn's post-hoc), considering a significance level of 5%. Comparison of metabolomic profiles between groups will be performed by univariate (ANOVA) and multivariate (PLS-DA and VIP scores; sPLS-DA and loadings) analyses. Discriminant metabolites will be correlated with periodontal clinical parameters. Finally, altered metabolic pathways associated with the progression of periodontitis during pregnancy will be mapped by Metabolite Set Enrichment Analysis (MSEA). This study is expected to identify salivary metabolomic signatures associated with the different stages of periodontitis in pregnant women. The characterization of these profiles may clarify biochemical mechanisms modulated by the interaction between pregnancy and periodontitis progression, in addition to revealing metabolic pathways with potential pathophysiological relevance. These findings may support non-invasive and personalized diagnostic strategies in maternal oral health, with future applications in predictive models.