Maternal exposure to plastic waste from a DOHaD perspective: influence of environmental stressors on the liver of rats

• Grant number: 24/09367-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2024
• End date: July 31, 2026
• Field of knowledge: Biological Sciences - Morphology - Embryology
• Principal Investigator: Wellerson Rodrigo Scarano
• Grantee: Gabriel Aquino de Souza Maia
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Plastic and its additives are increasingly becoming a problem for the environment and public health. In this context, plastics, once discarded, undergo degradation into smaller particles, called micro/nanoplastics, which have been gaining prominence due to the increase in evidence of these particles in the environment and their harmful properties to human health. These residues can also bind to various environmental contaminants and serve as transport of these substances to the human body, triggering a bioaccumulation process. Among these substances that can be adsorbed, there is a group classified as endocrine disruptors (EDs), which are phthalates, frequently used as plasticizers, which, as they do not have a covalent bond, leach from the polymers used into air, water and dust. , becoming omnipresent in the environment. Inserted in this context, the concept of the Developmental Origins of Health and Disease (DOHaD) postulates that adversities during pregnancy and/or lactation can have repercussions on the offspring, affecting various organs and systems, an effect called fetal programming. Thus, maternal exposure to plastic and nanoplastic additives can impact the development and modulation of the liver epigenome, the main metabolizer of these substances, leading to tissue, systemic and pathological changes. Therefore, the objective of this work is to evaluate the effects of exposure to nanoplastics and phthalates during pregnancy/lactation, on the offspring's liver, immediately after weaning. For this, pregnant SD rats will be divided into 4 groups: C: (control; vehicle); T1: 20¼g/kg/day of the phthalate mixture (MF); T2: 1mg/kg/day of 100 nm nanoplastics (NPs); T3: 20¼g/kg/day MF + 1mg/kg/day NPs 100 nm. Treatment will be administered orally, from gestational day 10 (GD10) to postnatal day (DPN 21), covering the gestational and lactational period. After weaning, at DPN22 (immediate effect), the male and female offspring will have their liver collected for histological analyzes (HE, PAS, reticulin and picrosirius). Furthermore, the activity of metalloproteinases will be measured by zymography, plasma liver function enzymes (ALT and AST) by colorimetry and the evaluation of some specific targets by qRT-PCR.