Histological evaluation of rat calvaria bone repair defects after local aplication of macrophage conditioned medium

• Grant number: 20/16711-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2021
• End date: April 30, 2022
• Field of knowledge: Biological Sciences - Morphology - Histology
• Principal Investigator: Karina Fittipaldi Bombonato Prado
• Grantee: Sayuri Poli Suguimoto
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Bone repair is a complex but highly organized process that involves interactions between various types of cells and the extracellular environment. Studies have shown that macrophages contribute to homeostasis and bone regeneration, promoting matrix mineralization by osteoblasts derived from calvaria. Therefore, the objective of the present project will be to carry out the qualitative and quantitative histological analysis of bone neoformation in the presence of conditioned medium of macrophages activated in M2 applied in the region of bone defect in the calvaria of rats. After the storage of conditioned medium and the creation of bone defects in the calvaria of rats, the conditioned medium will be applied in the region of the defect, once a week for 4 weeks, until euthanasia. The rats will be divided into three groups: Group 1 - control; Group 2 - application of 50 ¼l conditioned medium in the defect region; Group 3 - application of 50 ¼l vehicle (distilled water) in the defect region. After that, the samples will be collected for histological processing. The qualitative histological analysis of the histological plates will be performed using HE and Masson Trichrome images. The quantitative histological analysis of the newly formed bone trabeculate will be performed using Image J software. The data obtained will be analyzed by statistical programs consistent with significance p<0.05, with the goal of finding statistically significant data that demonstrate the effects of the conditioned medium on the bone repair of defects created in the calvaria of female rats. (AU)