Resposta de fibroblastos da gengiva de pacientes jovens e idosos e efeito da laserterapia de baixa potência e de fator de crescimento sobre estas células

Abstract

The age as well as the presence of inflammation can influence the cellular metabolism, slowing the tissue healing process. Different therapies, such as the application of growth factors and low level laser therapy (LLLT) are capable of biostimulating cells by increasing their proliferation and metabolism. The aim of this study was to evaluate: the functions of gingival fibroblasts obtained from young and elderly individuals (Study 1); the response of these cells exposed to tumor necrosis factor alpha - TNF-α (Study 2); and the effect of LLLT or epidermal growth factor - EGF on the viability and metabolism of these connective cell type (Study 3). Primary culture of gingival fibroblasts of 6 patients (3 young - Y and 3 elderly - E) were collected and cultured in complete culture medium (DMEM). In the Study 1 fibroblasts were seeded in 96-well plates in complete DMEM containing 10% of fetal bovine serum (FBS) for 24, 48 or 72 hours and subjected to evaluation of cell viability (MTT, n=36), total protein production (TP, n=36) and collagen synthesis (SR, n=36). In the Study 2, after 24-hour cell seeding, the complete DMEM was replaced by DMEM without FBS supplemented or not with TNF-α (100 ng/mL) which was kept in contact with cells for additional 24 hours. Then, the production of reactive oxygen TNF-α species (ROS, n=36), nitric oxide (NO, n=36) and synthesis of CCL5 chemokine (ELISA, n=36) were assessed. In the Study 3 fibroblasts were seeded in 24-well plates for 24 hours, and then exposed to EGF (100 μM) or submitted to low power laser irradiation (LASERTable device, InGaAsP - 780 ± 3nm; 25mW). Cell viability (Alamar Blue®, n=12), cell migration (Wound Healing, n=12), collagen synthesis (SR, n=12), and synthesis of vascular endothelial growth factor - VEGF (ELISA, n=12) were assessed 72 hours after the treatments. The data were statistical...(Complete abstract electronic access below)