Microplastics as a triggering factor of cellular oxidatice stress: in vitro study in primary fibroplastics

• Grant number: 25/16312-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2025
• End date: September 30, 2026
• Field of knowledge: Health Sciences - Dentistry - Periodontology
• Principal Investigator: Mabelle de Freitas Monteiro
• Grantee: Lorena Pagotto Spinace
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

The increasing presence of micro- and nanoplastics (NPMs) in the environment and their interaction with biological tissues have raised concerns about their impact on human health. Studies have shown that NPMs can cross cellular barriers, inducing oxidative stress, mitochondrial dysfunction, and activation of inflammatory responses in various organs. However, little is known about its effects on the tissues of the oral cavity, particularly on gingival fibroblasts, essential cells in the maintenance of periodontal homeostasis. Continuous exposure to dental materials, such as composite resins and acrylic prostheses, can represent a relevant source of plastic particle release into the mouth, making this environment especially vulnerable. Preliminary data obtained by transmission electron microscopy (TEM) by this research group demonstrated the internalization of NPMs in gingival fibroblasts, with morphological changes suggestive of cellular stress and inflammation. In this context, this study aims to evaluate the impact of exposure to MNPs on the expression of SOD1 (related to oxidative stress control) and PTEN (involved in the PI3K/AKT signaling pathway) genes in primary human gingival fibroblasts of three distinct cell populations. Additionally, the possible influence of these alterations on the expression of the pro-inflammatory cytokines IL-1¿ and TNF-¿, responsible for initiating the tissue inflammatory response and associated with the pathogenesis of periodontitis, will be investigated. For this, primary fibroblasts obtained from periodontally healthy individuals will be cultured and exposed to different concentrations of polystyrene MNPs, and cell viability analysis, RNA extraction and evaluation of gene expression by rt-PCR will be performed. The data obtained will allow us to understand whether NPMs act as modulators of the gingival inflammatory response, contributing to the redox imbalance and to the dysregulation of critical pathways involved in the maintenance of periodontal homeostasis. This study seeks to provide new evidence on the risks of environmental and iatrogenic exposure to NPMs on oral health, as well as to identify potential molecular mechanisms involved in their pathogenic action.