Effect of frog skin with or without photobiomodulation on skin repair: an "in vitro" and "in vivo" study

• Grant number: 23/10998-0
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2024
• End date: October 31, 2026
• Field of knowledge: Engineering - Biomedical Engineering
• Principal Investigator: Lívia Assis Garcia
• Grantee: Lívia Assis Garcia
• Host Institution: Universidade Brasil. Campus São Paulo. São Paulo , SP, Brazil
• Associated researchers: Ana Claudia Muniz Renno ; Ana Laura Martins de Andrade ; Carla Roberta Tim ; Cintia Cristina Santi Martignago ; Marcello Magri Amaral

Abstract

Skin wounds are frequent injuries observed in clinical practice and are related to high costs for the healthcare system as well as significant functional disability, pain and even death. In this context, it is extremely necessary to carry out research that develops increasingly innovative therapeutic interventions that combine effectiveness and low cost. Within this perspective, tissue engineering has assumed a prominent role in the development of new skin dressings and therapeutic resources with the aim of accelerating wound repair. Therefore, the objectives of this study are: (i): to evaluate the biological performance, through in vitro studies, of frog skin associated with photobiomodulation (FBM); (ii) evaluate the antimicrobial potential, through in vitro studies, of frog skin; (iii) evaluate the biological performance, through in vivo studies, of frog skin associated with FBM in the repair of skin wounds in an experimental model in rats. It is worth noting that our group already has expertise with pilot studies that used frog skin. Therefore, this project will be developed in the following stages: obtaining Bullfrog skin (Lithobates Catesbeiana) and its bioactive characterization. Next, in vitro antimicrobial tests will be carried out [for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli)], biocompatibility (HFF-1 fibroblasts and HEKa keratinocytes) and in vivo (Wistar rats, males in an experimental model of excisional wound with a diameter of 10 mm) through the following groups: Control (GG); Frog skin (PR): treatment with frog skin; Laser FBM (FBM): treatment with FBM; Frog skin + laser FBM (PRFBM): treatment with frog skin and irradiated with laser FBM. The laser FBM device used will be with a 660 nm Gallium Arsenide, Indium, Aluminum and Phosphorus pen with a beam area of 0.028 cm2, power of 40 mW, energy of 1.5 J and in continuous emission mode. In the in vitro study, the antimicrobial potential will be evaluated by counting colony-forming units; biocompatibility assessment will be carried out through viability and cytotoxicity and cell proliferation tests in three periods (24, 72 and 120 hours); The effectiveness of in vivo treatments will be evaluated through the wound healing rate, descriptive histological evaluations, number of inflammatory cells, fibroblasts and blood vessels, re-epithelialization and area of granulation tissue, histomorphometric analysis of colgagenesis by imaging and the immunoexpression of IL- 1², Collagen I and III, VEGF and TGF-². Furthermore, analysis will be carried out to analyze the levels of myeloperoxidase (MPO), N-acetylglucosaminidase (NAG) and hydroxyproline (HYP). It is expected that this study will contribute to the development of new therapeutic interventions, using national and natural biomaterials associated with FBM to promote skin repair. (AU)