RESUMO
OBJECTIVE: IL-17A is implicated in periodontitis pathogenesis. The roles of IL-17B-IL-17F and IL-17A/F are unknown. This study aimed to determine clinical associations between IL-17 family cytokines and periodontitis and to investigate the biological roles of IL-17A and IL-17E using in vitro model systems. MATERIALS AND METHODS: Samples from 97 patients with periodontitis and 77 healthy volunteers were used in the study. Serum, saliva and gingival crevicular fluid (GCF) levels of IL-17 family cytokines were measured by ELISA. Oral keratinocytes were stimulated with a P. gingivalis biofilm, or IL-17A, in the presence and absence of IL-17E and the expression of IL-8 and CXCL5 were investigated by ELISA and real-time-PCR. NF-κB phosphorylation in similar experiments was also measured using a cell-based ELISA. RESULTS: Serum, saliva and GCF IL-17A levels were higher in periodontitis patients and correlated positively with clinical parameters of attachment loss, pocket depth and bleeding on probing. Serum IL-17E levels were lower in periodontitis patients and the serum IL-17A:IL-17E ratio correlated positively with clinical parameters. In vitro, IL-17E inhibited Porphyromonas gingivalis and IL-17A induced expression of chemokines by reducing phosphorylation of the NF-κB p65 subunit. CONCLUSIONS: Serum IL-17A:IL-17E may be a marker of disease severity. IL-17E may have opposing roles to IL-17A in periodontitis pathogenesis. IL-17E can negatively regulate IL-17A and periodontal pathogen induced expression of chemokines by oral keratinocytes.
Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica , Interleucina-17/metabolismo , Periodontite/imunologia , Periodontite/metabolismo , Adulto , Biofilmes , Biomarcadores/sangue , Estudos de Casos e Controles , Técnicas de Cocultura , Ensaio de Imunoadsorção Enzimática , Feminino , Líquido do Sulco Gengival/imunologia , Humanos , Queratinócitos/citologia , Masculino , Pessoa de Meia-Idade , Porphyromonas gingivalis/metabolismoAssuntos
Preservativos/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde , Homossexualidade Masculina/estatística & dados numéricos , Profissionais do Sexo/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto , Alcoolismo/epidemiologia , Infecções por Chlamydia/epidemiologia , Estudos de Coortes , Gonorreia/epidemiologia , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Herpes Simples/epidemiologia , Pessoas Mal Alojadas/estatística & dados numéricos , Humanos , Masculino , Faringite/epidemiologia , Estupro/estatística & dados numéricos , Doenças Retais/epidemiologia , Estudos Retrospectivos , Escócia/epidemiologia , Profissionais do Sexo/psicologia , Comportamento Sexual/estatística & dados numéricosRESUMO
OBJECTIVE: The alpha 7 nicotinic receptor (α7nAChR) is expressed by oral keratinocytes. α7nAChR activation mediates anti-inflammatory responses. The objective of this study was to determine if α7nAChR activation inhibited pathogen-induced interleukin-8 (IL-8) expression by oral keratinocytes. MATERIALS AND METHODS: Periodontal tissue expression of α7nAChR was determined by real-time PCR. OKF6/TERT-2 oral keratinocytes were exposed to Porphyromonas gingivalis in the presence and absence of a α7nAChR agonist (PHA-543613 hydrochloride) alone or after pre-exposure to a specific α7nAChR antagonist (α-bungarotoxin). Interleukin-8 (IL-8) expression was measured by ELISA and real-time PCR. Phosphorylation of the NF-κB p65 subunit was determined using an NF-κB p65 profiler assay and STAT-3 activation by STAT-3 in-cell ELISA. The release of ACh from oral keratinocytes in response to P. gingivalis lipopolysaccharide was determined using a GeneBLAzer M3 CHO-K1-bla cell reporter assay. RESULTS: Expression of α7nAChR mRNA was elevated in diseased periodontal tissue. PHA-543613 hydrochloride inhibited P. gingivalis-induced expression of IL-8 at the transcriptional level. This effect was abolished when cells were pre-exposed to a specific α7nAChR antagonist, α-bungarotoxin. PHA-543613 hydrochloride downregulated NF-κB signalling through reduced phosphorylation of the NF-κB p65-subunit. In addition, PHA-543613 hydrochloride promoted STAT-3 signalling by maintenance of phosphorylation. Furthermore, oral keratinocytes upregulated ACh release in response to P. gingivalis lipopolysaccharide. CONCLUSION: These data suggest that α7nAChR plays a role in regulating the innate immune responses of oral keratinocytes.