The consequences of maternal malnutrition on metabolism and thyroid morphophysiology in rats

• Grant number: 23/03348-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2024
• End date: January 31, 2026
• Field of knowledge: Biological Sciences - Morphology - Histology
• Principal Investigator: Luis Antonio Justulin Junior
• Grantee: Ana Lívia Silvério Vieira
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Maternal malnutrition is a condition that encompasses several conditions, be they high-calorie and high-fat diets, as well as malnutrition and restriction of certain macromolecules. These parameters are linked to the concept of the Developmental Origins of Health and Disease (DOHaD), an area of knowledge that postulates that effects on the gestational and/or lactational environment can influence the most diverse organs and systems in the offspring. Thus, data from the literature demonstrate that maternal protein restriction (MPR) can affect the thyroid, leading to cellular stress and an imbalance in hormones that regulate basal metabolism. Therefore, the objective of this project is to evaluate whether RPM affects the morphophysiology of the thyroid in post-weaning and aging male rats, contrasting with histopathological, immunohistochemical and metabolic analyses. For this, male Sprague Dawley rats were used, divided into 2 groups: Rats born to mothers fed a normoprotein diet (CTR, 17% protein) or a hypoprotein diet (GLLP, 6% protein), during pregnancy and lactation. Some of the animals were euthanized on postnatal day (PND) 21, and the other part consumed standard protein food until PND540, at which time they were euthanized, with thyroids and blood collected. The thyroids were processed, and morphological parameters (hematoxylin-eosin and toluidine blue), morphometric parameters (size of thyroid follicles and cells), histopathological analyses, measurement of T3, free T3 and T4 levels in the blood and immunological analyzes will be analyzed. histochemical tests to evaluate the recruitment of inflammatory cells (CD4, CD8 and CD68) and cell proliferation (Ki67). Thus, the expected results are that there will be negative effects on the morphophysiology of the thyroids both in early life and aging, which can lead to negative effects on the thyroid and the entire systemic environment, impacting developmental biology in different windows of susceptibility. .Keywords: DOHaD, Maternal protein restriction, Thyroid, Hormones, Immune system.