Biological and anti-inflammatory properties of Pelargonium sidoides in human apical papilla cells and local and systemic changes after carrageenan-induced rat paw inflammation

• Grant number: 24/07121-2
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: October 01, 2024
• End date: March 31, 2025
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Lívia Nordi Dovigo
• Grantee: Sâmmea Martins Vieira
• Supervisor: Joao Miguel Marques dos Santos
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Institution abroad: Faculdade De Medicina Da Universidade De Coimbra, Portugal
• Associated to the scholarship: 22/12580-0 - Antimicrobial potential of Pelargonium sidoides and an isolated coumarin, associated or not with light and ultrasound, against microorganisms in root infections, BP.DR

Abstract

Endodontic infections can reach the periapical tissues, which leads to the presence of inflammation and bone resorption, causing the production of pro-inflammatory cytokines, osteoclastogenesis and the action of enzymes. Pelargonium medoides is a natural compound extracted from a plant of African origin, effective in respiratory infections with immunomodulatory and anti-inflammatory properties. Therefore, the objective of this study will be to investigate the biological and anti-inflammatory properties of P. medoides through in vitro analysis on human apical papilla cells (APCs) and in vivo, through the formation of edema in rat paws. A P.sidoides solution available for sale in Brazilian pharmacies (Kaloba, Farmoquímica S/A) and the P.sidoides extract obtained from the company Dr. Willmar Schwabe GmbH & Co. KG (Karlsruhe, Germany) will be used. For in vitro evaluation, APCs will be collected from third molars with incomplete rhizogenesis from donors. After culture, analysis for differentiation and flow cytometry will be carried out to determine proteins expressed on its surface. Cell viability will be determined by the Alamar Blue assay and cell migration and proliferation will be assessed by the "scratch assay". Quantification of nitric oxide will be carried out by spectrophotometry and analysis of gene expression will be carried out by quantification of the polymerase chain reaction in real time. For in vivo evaluation, 42 male Sprague-Dawley rats will be used, after approval by the ethics and animal welfare committee. The rats will be divided into four experimental groups (n=6, each). To induce inflammation, carrageenan will be used with injection into the plantar surface of the right hind paw. Then, treatments will be carried out. The mice will be euthanized and both hind legs will be cut off and weighed on a digital scale. The degree of paw swelling, edema inhibition rate and paw volume will be calculated. The right hind paws will be collected for subsequent hematoxylin-eosin and immunohistochemistry analysis. The results will be analyzed with descriptive statistics and, depending on the study, ANOVA with one factor or two fixed factors and confidence intervals for means (±=0.05).