Effects of corticosterone on the distribution of myofibroblasts in the gastric mucosa during postnatal development.

• Grant number: 22/13200-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2022
• End date: June 30, 2024
• Field of knowledge: Biological Sciences - Morphology - Cytology and Cell Biology
• Principal Investigator: Patrícia Gama
• Grantee: Mariana Akemi Alves Kuriyama
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

In the stomach the region of the gastric corpus contains glands that are divided into three segments: isthmus, colon and base, each containing different epithelial cells and these are responsible for tissue renewal, production of molecules that act in food digestion, mucosa protection and hormone secretion. Two proliferative niches are identified, one active at the isthmus-neck interface and the other reserve in which cells cycle more slowly at the base of the gland. Changes in feeding patterns during postnatal development such as early weaning can alter proliferative niches and affect cell distribution in each region. Associated with the epithelial tissue are myofibroblasts which are modified fibroblasts present in the connective tissue (lamina propria) which usually differentiate in the face of tissue injury, performing a repair function. These cells produce and/or have associated molecules that can alter the proliferative niche and, thereby, modify the activity and distribution of cells. The present project aims to identify myofibroblasts and study their secretory activity in the gastric mucosa and investigate the possible relationship and interference of these cells in the proliferation of glandular cells. Additionally we intend to study the distribution of myofibroblasts under blockade of glucocorticoid receptors which are regulatory agents of cell proliferation. For this, immunofluorescence techniques will be used in stomach samples from 18 and 30 days old rats submitted to early weaning (15th day) compared to normally breastfed animals.