Frederico C Martinho1, Fabio R M Leite2, Wanderson M M Chiesa3, Gustavo G Nascimento2, Magda Feres4, Brenda P F A Gomes5. 1. Department of Restorative Dentistry, Endodontics Division, UNESP-UNIV Estadual Paulista, São José dos Campos Dental School, São José dos Campos, São Paulo, Brazil; Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas, UNICAMP, Piracicaba, São Paulo, Brazil. 2. Department of Semiology and Clinics, Periodontics Division, Federal University of Pelotas, School of Dentistry, UFPel, Pelotas, Rio Grande do Sul, Brazil. 3. Department of Restorative Dentistry, Endodontics Division, Amazonas State University, Manaus, Amazonas, Brazil. 4. Dental Research Division, Department of Periodontology, Guarulhos University, Guarulhos, São Paulo, Brazil. 5. Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas, UNICAMP, Piracicaba, São Paulo, Brazil. Electronic address: bpgomes@fop.unicamp.br.
Abstract
INTRODUCTION: This study investigated the bacterial community involved in primary endodontic diseases, evaluated its ability to activate the macrophage Toll-like receptor 4 receptor through p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signaling pathways, and determined the levels of endotoxins and interleukins (interleukin [IL]-6 and -10) produced by endodontic content-stimulated macrophages. METHODS: Samples were taken from 21 root canals by using sterile/apyrogenic paper points. Raw 264.7 macrophages were stimulated with root canal contents. Checkerboard DNA-DNA hybridization was used for bacterial analysis and the limulus amebocyte lysate assay for endotoxin measurement; p38 MAPK and NF-κB activation was determined by Western blot analysis. IL-6 and IL-10 were measured using the enzyme-linked immunosorbent assay. RESULTS: Bacteria and endotoxins were detected in 100% of the samples (21/21). The most frequently observed species were Parvimonas micra (16/21, 76%), Fusobacterium nucleatum ssp. nucleatum (15/21, 71%), and Porphyromonas endodontalis (14/21, 66%). Correlations were found between endotoxins and IL-6 and IL-10 (P < .05); p38 phosphorylation had a peak at 60 minutes, and NF-κB was quickly activated after 10 minutes of stimulation. CONCLUSIONS: It was concluded that the complex bacterial community was shown to be a potent activator of TLR-4 determined by the p38 MAPK and NF-κB signaling pathways, culminating in a high antigenicity against macrophages through the levels of IL-6 and IL-10, all significantly affected by endotoxin levels.
INTRODUCTION: This study investigated the bacterial community involved in primary endodontic diseases, evaluated its ability to activate the macrophage Toll-like receptor 4 receptor through p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signaling pathways, and determined the levels of endotoxins and interleukins (interleukin [IL]-6 and -10) produced by endodontic content-stimulated macrophages. METHODS: Samples were taken from 21 root canals by using sterile/apyrogenic paper points. Raw 264.7 macrophages were stimulated with root canal contents. Checkerboard DNA-DNA hybridization was used for bacterial analysis and the limulus amebocyte lysate assay for endotoxin measurement; p38 MAPK and NF-κB activation was determined by Western blot analysis. IL-6 and IL-10 were measured using the enzyme-linked immunosorbent assay. RESULTS: Bacteria and endotoxins were detected in 100% of the samples (21/21). The most frequently observed species were Parvimonas micra (16/21, 76%), Fusobacterium nucleatum ssp. nucleatum (15/21, 71%), and Porphyromonas endodontalis (14/21, 66%). Correlations were found between endotoxins and IL-6 and IL-10 (P < .05); p38 phosphorylation had a peak at 60 minutes, and NF-κB was quickly activated after 10 minutes of stimulation. CONCLUSIONS: It was concluded that the complex bacterial community was shown to be a potent activator of TLR-4 determined by the p38 MAPK and NF-κB signaling pathways, culminating in a high antigenicity against macrophages through the levels of IL-6 and IL-10, all significantly affected by endotoxin levels.
Authors: Frederico C Martinho; Bruna J M Corazza; Rayana D Khoury; Esteban I F Orozco; Cassia C Toia; Felipe P Machado; Marcia C Valera Journal: Clin Oral Investig Date: 2022-06-20 Impact factor: 3.573
Authors: Frederico C Martinho; Fábio R M Leite; Gustavo G Nascimento; Joni A Cirelli; Brenda P F A Gomes Journal: Clin Oral Investig Date: 2014-02-13 Impact factor: 3.573
Authors: Johnathan P Velardi; Theeb A Alquria; Rayyan A Alfirdous; Bruna J M Corazza; Ana P M Gomes; Eduardo G Silva; Ina L Griffin; Patricia A Tordik; Frederico C Martinho Journal: Sci Rep Date: 2022-03-22 Impact factor: 4.379
Authors: Benjamín Briseño-Marroquín; Angelika Callaway; Natascha Gol Shalamzari; Thomas Gerhard Wolf Journal: BMC Oral Health Date: 2022-04-09 Impact factor: 2.757