Analysis of salivary protein biomarkers and enzymatic activity in pregnant women at different stages of periodontitis

• Grant number: 25/21307-4
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: December 15, 2025
• End date: February 14, 2026
• Field of knowledge: Health Sciences - Dentistry - Pediatric Dentistry
• Principal Investigator: Gerson Aparecido Foratori Junior
• Grantee: Amanda Borges Pirondi
• Supervisor: Nagihan Bostanci
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil
• Institution abroad: Karolinska Institutet, Sweden
• Associated to the scholarship: 24/01759-5 - High-risk pregnancy in Primary Care: analysis periodontal condition-related quality of life and associated risk factors, BP.IC

Abstract

Pregnancy is a physiological state marked by profound hormonal and immunological adaptations that can exacerbate the inflammatory response to dental biofilm, increasing susceptibility to periodontal diseases. Periodontitis, a chronic and multifactorial condition characterized by connective tissue destruction and alveolar bone loss, has been associated with adverse maternal and neonatal outcomes. Saliva, as a non-invasive and information-rich biological fluid, represents a promising matrix for the identification of biomarkers that reflect both inflammatory burden and extracellular matrix degradation during pregnancy. This project aims to validate salivary proteins previously identified in proteomic discovery analyses and to investigate their functional relevance through enzymatic activity assays. Pregnant women are being consecutively recruited from Primary Health Units in the city of Bauru-SP and classified according to the 2017 World Workshop classification of periodontitis. The sample is composed of four groups: stage I (G1 = 10), stage II (G2 = 10), stage III (G3 = 10), and control group without periodontitis (G4 = 10). Unstimulated saliva samples stored at ¿80 °C will be analyzed individually to quantify neutrophil-related biomarkers, such as lactotransferrin (LTF), lipocalin-2/NGAL, and neutrophil elastase-2 (ELA2), using bead-based multiplex immunoassays (MILLIPLEX® technology). In parallel, gelatin zymography will be performed to determine the functional activity of matrix metalloproteinases (MMP-2 and MMP-9), integrating protein abundance with proteolytic potential. Statistical analysis of quantitative variables will be preceded by normality and homogeneity tests. Variables with normal distribution and homoscedasticity will be compared between groups using ANOVA with Tukey's post-hoc test, whereas variables without normal distribution or homogeneity of variance, as well as ordinal qualitative variables, will be analyzed using the Kruskal-Wallis test with Dunn's post-hoc. Nominal qualitative variables will be assessed using the Chi-square test. A significance level of 5% will be adopted. This combined approach is expected to identify possible biologically relevant salivary biomarkers and functional signatures across different stages of gestational periodontitis, contributing to early detection, risk stratification, and a deeper understanding of molecular mechanisms underlying periodontal destruction in pregnancy.