Tumor necrosis factor-like weak inducer of apoptosis increases CC chemokine ligand 20 production in interleukin 1ß-stimulated human gingival fibroblasts.

CC chemokine ligand 20 (CCL20) is related to T-helper (Th)-17 cell migration, and Th17 cells play important roles in exacerbation in periodontal disease. However, the effect of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) on CCL20 production is unknown. In this study, we examined the mechanisms of TWEAK in combination with interleukin (IL)-1ß-induced CCL20 production in human gingival fibroblasts (HGFs). TWEAK alone did not induce CCL20 production in HGFs. However, TWEAK enhanced CCL20 expression from IL-1ß-stimulated HGFs in a dose-dependent manner. Inhibitors of p38 mitogen-activated protein kinase, extracellular signal-regulated kinase (ERK), protein kinase B (Akt), and nuclear factor κB (NF-κB) significantly inhibited CCL20 production in TWEAK and IL-1ß-stimulated HGFs. Western blot analysis revealed that phosphorylations of ERK, Akt, and inhibitor of NF-κB were enhanced in TWEAK and IL-1ß-treated HGFs. These data suggest that TWEAK is positively related to Th17 cell migration in periodontally diseased tissues to enhance CCL20 production in IL-1ß-stimulated HGFs.

Interleukin (IL)-17A synergistically enhances CC chemokine ligand 20 production in IL-1ß-stimulated human gingival fibroblasts.

CC chemokine ligand 20 (CCL20) plays a pivotal role in the recruitment of T-helper (Th)-17 cells and thus in the development of periodontal disease, but the effect of simultaneous interleukin (IL)-17A and IL-1ß stimulation on CCL20 production in human gingival fibroblasts (HGFs) are not known. In this study, we investigated the mechanisms of IL-1ß- and IL-17A-induced CCL20 production in HGFs. IL-17A synergistically enhanced CCL20 production from IL-1ß-stimulated HGFs in a concentration-dependent manner. Extracellular signal-regulated kinase (ERK) and inhibitor of nuclear factor (NF)-κB-α phosphorylation were increased in IL-1ß- and IL-17A-stimulated HGFs. Inhibitors of or ERK and NF-κB decreased IL-1ß- and IL-17A-induced CCL20 production. IL-1ß stimulation elevated IL-17 receptor C expression on HGFs. These data suggest that IL-1ß is actively related to Th17 cell migration into peripheral tissues to induce production of the Th17 chemokine, CCL20. Therefore, IL-1ß might be a therapeutic target for Th17-related diseases, such as periodontal disease and arthritis.

Black tea polyphenol inhibits CXCL10 production in oncostatin M-stimulated human gingival fibroblasts.

CXC chemokine ligand 10 (CXCL10) plays an important role in the infiltration of Th1 cells and thus in the exacerbation of periodontal disease. Theaflavin-3,3'-digallate (TFDG), polyphenol in black tea, has some beneficial effects but the effect of TFDG on CXCL10 production from human gingival fibroblasts (HGFs) is uncertain. In this study, we investigated the mechanisms by which TFDG may inhibit oncostatin M (OSM)-induced CXCL10 production in human gingival fibroblasts. TFDG prevented OSM-mediated CXCL10 production by HGFs in a dose dependent manner. TFDG significantly inhibited OSM-induced phosphorylation of c-Jun N terminal kinase (JNK), protein kinase B (Akt) (Ser473) that are related to CXCL10 production from OSM-stimulated HGFs. In addition, TFDG suppressed OSM receptor (OSMR) ß expression on HGFs. These data provide a novel mechanism where the black tea flavonoid, theaflavin, could provide direct benefits in periodontal disease.

Oncostatin M synergistically induces CXCL10 and ICAM-1 expression in IL-1beta-stimulated-human gingival fibroblasts.

Periodontitis is a chronic bacterial infection of tooth-supporting structures. T-helper type 1 (Th1) cells are related to the exacerbation of periodontal disease. Human gingival fibroblasts (HGFs), the major cell type in periodontal connective tissues, are involved in immunological response in periodontal tissues. However, it is uncertain whether HGFs are related to Th1 response. Chemokine (C-X-C motif) ligand 10 (CXCL10) is a cytokine, that is related to Th1 cells migration. Intercellular adhesion molecule (ICAM)-1 is involved in Th1 cells retention and activation in inflamed tissue. The aim of this study is to examine the effect of oncostatin M (OSM) on CXCL10 and ICAM-1 expression in HGFs. OSM stimulation induced CXCL10 and ICAM-1 expression in HGFs. Moreover, the synergistic effects of CXCL10 release and ICAM-1 expression in HGFs were observed with combined stimulation of interleukin (IL)-1beta and OSM. OSM increased type 1 IL-1 receptor (IL-1R1) expression, and IL-1beta enhanced OSMRbeta expression on HGFs. IL-1beta + OSM stimulation enhanced the phosphorylation of inhibitor of nuclear factor kappaB (IkappaB)-alpha, signal transducer and activator of transcription (STAT)3, c-Jun N terminal kinase (JNK), and protein kinase B (Akt) compared to OSM or IL-1beta stimulation. CXCL10 production from OSM + IL-1beta stimulated HGFs was suppressed by nuclear factor (NF)-kappaB, STAT3, JNK, and phosphoinositide-3-kinase (PI3K) inhibitors. On the other hand, only NF-kappaB and STAT3 inhibitors suppressed ICAM-1 expression enhanced by OSM + IL-1beta treatment. These effects of OSM and IL-1beta may promote Th1 cells infiltration and retention in periodontally diseased tissues and be related to exacerbation of periodontal disease.

Tea polyphenols inhibit IL-6 production in tumor necrosis factor superfamily 14-stimulated human gingival fibroblasts.

IL-6 is well recognized to be a potent bone resorptive agent and thus in the development of periodontal disease. Epigallocatechin gallate (EGCG) and epicatechin gallate (ECG), the major catechins in green tea, and theaflavin-3,3'-digallate (TFDG), polyphenol in black tea, have multiple beneficial effects, but the effects of catechins and theaflavins on IL-6 production in human gingival fibroblasts (HGFs) are not known. In this study, we investigated the mechanisms by which EGCG, ECG, and TFDG inhibit tumor necrosis factor superfamily 14 (TNFSF14)-induced IL-6 production in HGFs. We detected TNFSF14 mRNA expression in human diseased periodontal tissues. TNFSF14 increased IL-6 production in HGFs in a concentration-dependent manner. EGCG, ECG, and TFDG prevented TNFSF14-mediated IL-6 production in HGFs. EGCG, ECG, and TFDG prevented TNFSF14-induced extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and nuclear factor-kappaB activation in HGFs. Inhibitors of ERK, JNK, and nuclear factor-kappaB decreased TNFSF14-induced IL-6 production. In addition, EGCG, ECG, and TFDG attenuated TNFSF14 receptor expression on HGFs. These data provide a novel mechanism through which the green tea and black tea polyphenols could be used to provide direct benefits in periodontal disease.

Catechins inhibit CXCL10 production from oncostatin M-stimulated human gingival fibroblasts.

CXC chemokine ligand 10 (CXCL10) plays a pivotal role in the recruitment of Th1 cells and, thus, in the development of periodontal disease. Epigallocatechin gallate (EGCG) and epicatechin gallate (ECG), the major catechins derived from green tea, have multiple beneficial effects, but the effects of catechins on CXCL10 production from human gingival fibroblasts (HGFs) is not known. In this study, we investigated the mechanisms by which EGCG and ECG inhibit oncostatin M (OSM)-induced CXCL10 production in HGFs. HGFs constitutively expressed glycoprotein 130 and OSM receptor beta (OSMR beta), which are OSM receptors. OSM increased CXCL10 production in a concentration-dependent manner. EGCG and ECG prevented OSM-mediated CXCL10 production by HGFs. Inhibitors of p38 mitogen-activated protein kinase, c-Jun N-terminal kinase (JNK), phosphatidylinositol-3-OH kinase and signal transducer and activator of transcription (STAT)3 decreased OSM-induced CXCL10 production. EGCG significantly prevented OSM-induced phosphorylation of JNK, Akt (Ser473) and STAT3 (Tyr705 and Ser727). ECG prevented phosphorylation of JNK and Akt (Ser473). In addition, EGCG and ECG attenuated OSMR beta expression on HGFs. These data provide a novel mechanism through which the green tea flavonoids, catechins, can provide direct benefits in periodontal disease.

TNFSF14 coordinately enhances CXCL10 and CXCL11 productions from IFN-gamma-stimulated human gingival fibroblasts.

TNFSF14 is involved in the pathogenesis of some inflammatory diseases such as arthritis. CXCL10 and CXCL11 recruit Th1 cells, and the productions of these chemokines are related to the exacerbation of some inflammatory diseases including arthritis and periodontal disease. We examined in vitro effects of TNFSF14 on IFN-gamma-induced CXCL10 and CXCL11 production in human gingival fibroblasts (HGFs). HGFs constitutively expressed TNFSF14 receptors, LTbetaR and HVEM. TNFSF14 enhanced IFN-gamma-induced secretion of CXCL10 and CXCL11 from HGFs. IFN-gamma treatment increased HVEM expression on HGFs. TNFSF14 in combination with IFN-gamma resulted in increased activation of p38 MAPK, ERK and IkappaB-alpha compared with TNFSF14 or IFN-gamma alone. Moreover, inhibitors of p38 MAPK, ERK and NF-kappaB abolished the CXCL10 and CXCL11 productions from TNFSF14 with IFN-gamma-stimulated HGFs. These effects of TNFSF14 may promote the infiltration of Th1 cells into lesions with inflammatory diseases. TNFSF14 might act as a proinflammatory cytokine in some inflammatory diseases thus is a candidate therapeutic target.

Catechins inhibit CCL20 production in IL-17A-stimulated human gingival fibroblasts.

CC chemokine ligand 20 (CCL20) plays a pivotal role in the recruitment of Th17 cells and thus in the development of periodontal disease. Epigallocatechin gallate (EGCG) and epicatechin gallate (ECG), the major catechins in green tea, have multiple beneficial effects, but the effects of catechins on CCL20 production in human gingival fibroblasts (HGFs) are not known. In this study, we investigated the mechanisms by which EGCG and ECG inhibit interleukin (IL)-17A-induced CCL20 production in human gingival fibroblasts. IL-17A increased CCL20 production in HGFs in a concentration-dependent manner. EGCG and ECG prevented IL-17A-mediated CCL20 production in HGFs. Inhibitors of p38 mitogen-activated protein kinase (MAPK) or extracellular signal-regulated kinase (ERK) decreased IL-17A-induced CCL20 production. EGCG and ECG prevented IL-17A-induced phosphorylation of p38 MAPK and ERK in HGFs. In addition, EGCG and ECG attenuated IL-17 receptor expression on HGFs. These data provide a novel mechanism through which the green tea flavonoids catechins could be used to provide direct benefits in periodontal disease.

Expression of macrophage inflammatory protein 3alpha in human inflamed dental pulp tissue.

Severe pulpitis resulting from dental caries is characterized by marked inflammatory infiltrate such as lymphocytes. Little is known about the recruitment of these cells into the dental pulp lesions of carious teeth. Macrophage inflammatory protein-3alpha (MIP-3alpha), a CC chemokine attracts CC chemokine receptor 6 (CCR6)-expressing T cells. We examined the distribution of MIP-3alpha-positive and/or CCR6-positive cells in human inflamed and normal dental pulp by immunohistochemistry. MIP-3alpha was observed in all inflamed pulp sections, and was mostly distributed in macrophages that had accumulated in the area adjacent to carious lesions. Furthermore, CCR6 expression was also observed in the infiltrating lymphocytes. In contrast, MIP-3alpha and CCR6 were rarely detected in normal pulp. These findings suggest that MIP-3alpha plays a role in the advancement of pulpal inflammation via the recruitment of CCR6-expressing lymphocytes.

N-acetyl-D-galactosamine specific lectin of Eikenella corrodens induces intercellular adhesion molecule-1 (ICAM-1) production by human oral epithelial cells.

During the acute inflammatory response in periodontitis, gingival epithelial cells are considered to play important roles in the recruitment of inflammatory cells to the site of infection through the secretion of chemokines. However, little is known about the expression of molecules that are involved in the interaction between the epithelium and neutrophils following bacterial attachment. Earlier work reported that periodontopathogenic Eikenella corrodens strain 1,073 up-regulated the expression and secretion of chemokines such as interleukin-8 (IL-8) from KB cells (a human oral epithelial cell line derived from a human oral epidermoid carcinoma). To elucidate the mechanism of the transmigration of neutrophils through the epithelium, the present study investigated the expression of adhesion molecules on KB cells in response to E. corrodens attachment. Adhesion molecule gene expression was assessed by RT-PCR and adhesion proteins expressed on KB cell surfaces were determined by cell-based ELISA and FACS. In RT-PCR, ICAM-1 mRNA levels were significantly increased within 1 h in response to exposure to E. corrodens and continued to increase over the 12-h period of study. In ELISA, increased surface ICAM-1 expression was paralleled by increased ICAM-1 mRNA levels. Furthermore, the increases in ICAM-1 expression on epithelial cells infected with E. corrodens were observed to be due to the N-acetyl-D-galactosamine (GalNAc) specific bacterial lectin-like substance of E. corrodens (EcLS), which was one of the adhesins of E. corrodens. This is the first study to report that a bacterial lectin-like substance increased the expression of ICAM-1 on gingival epithelial cells.