Cardamonin inhibits the expression of inflammatory mediators in TNF-α-stimulated human periodontal ligament cells.

OBJECTIVE: Periodontis is a chronic inflammatory disease induced by periodontopathogenic bacteria. The excessive immune response caused by persistent bacterial infection leads to alveolar bone resorption and ultimately tooth loss. Cardamonin is a biologically active substance that is found in the Zingiberaceae family, such as Alpinia zerumbet, and is classified as a natural chalcone. There have been no attempts to use cardamonin for the treatment of periodontitis, and no reports have examined the effects of cardamonin on periodontal tissue component cells. The aim of this study was to analyze effects of cardamonin on expression of inflammation mediators produced by TNFα-stimulated human periodontal ligament cells (HPDLCs), including its effects on signal transduction molecules. METHODS: Cytokine and chemokine levels were measured by ELISA. Protein expression in HPDLCs and activations of signal transduction pathway were determined by Western blotting. RESULTS: Our results indicate that cardamonin suppresses C-C motif chemokine ligand (CCL)2, CCL20, C-X-C motif chemokine ligand (CXCL)10, and interleukin (IL)-6 production and intercellular adhesion molecule (ICAM)-1 and cyclooxygenase (COX)-2 expression in TNF-α-stimulated HPDLCs. In addition, cardamonin induced the expression of the antioxidant enzyme, Heme Oxygenase (HO)-1, in HPDLCs. Furthermore, cardamonin suppressed TNF-α-stimulated c-Jun N-terminal kinase (JNK), nuclear factor (NF)-κB, and signal transducer and activator of transcription (STAT)3 signaling pathways in HPDLCs. CONCLUSION: We show that cardamonin reduces inflammatory mediator production by inhibiting the activation of several signaling pathways in this manuscript.

Cardamonin decreases inflammatory mediator expression in IL-1ß-stimulated human periodontal ligament cells.

BACKGROUND: Cardamonin is classified as a natural chalcone, and has been reported to possess various bioactive effects. However, there have been limited attempts to utilize cardamonin in the treatment of periodontitis. This study aimed to investigate whether cardamonin has anti-inflammatory effects on human periodontal ligament cells (HPDLCs), which are a component cell of periodontal tissue. Specifically, the study seeks to determine whether cardamonin affects the expression of inflammatory mediators, such as cytokines and adhesion molecules, induced by interleukin-1ß (IL-1ß) in HPDLCs, as well as the signaling pathways activated by IL-1ß. METHODS: Cytokine and chemokine levels in supernatants of HPDLCs were measured by ELISA. Western blot analysis was used to measure protein expression and signal transduction pathway activation in HPDLCs. RESULTS: We found that IL-1ß-induced CC chemokine ligand (CCL)2, CCL5, CCL20, CXC-chemokine ligand (CXCL)10, and interleukin (IL)-6 production and intercellular adhesion molecule (ICAM)-1 and cyclooxygenase (COX)-2 expression in HPDLCs were suppressed by cardamonin treatment. We also found that cardamonin suppressed IL-1ß-activated nuclear factor (NF)-κB pathway, and the phosphorylation of signal transducer and activator of transcription (STAT)3. Furthermore, cardamonin treatment enhanced the expression of the antioxidant enzymes, heme oxygenase (HO)-1 and NAD(P)H dehydrogenase [quinone] 1 (NQO1), in HPDLCs. CONCLUSION: In this study, we found that cardamonin could suppress the production of inflammatory mediators in HPDLCs as well as the activation of several signaling pathways induced by IL-1ß treatment.

The effects of berteroin on inflammatory mediators and antioxidant enzymes expression in human periodontal ligament cells.

Berteroin is a bioactive substance classified as an isothiocyanate found in cruciferous vegetables such as cabbage, arugula, and salad leaves. In this study, we aimed to determine whether berteroin exerts anti-inflammatory effects on human periodontal ligament cells (HPDLCs), a resident cells of periodontal tissue. Berteroin suppressed interleukin (IL)-1ß or tumor necrosis factor (TNF)-α-induced chemokines (C-C motif chemokine ligand (CCL)2, CCL20, C-X-C motif chemokine ligand (CXCL)10, IL-8, and IL-6) production and intercellular adhesion molecule (ICAM)-1 expression in HPDLCs. In addition, berteroin inhibited phosphorylation of IκB kinase (IKK)- α/ ß, nuclear factor (NF)- κB p65, and IκB- α and degradation of IκB- α in the NF-κB pathway induced by IL-1 ß or TNF- α stimulation. Moreover, berteroin could inhibit signal transducer and activator of transcription (STAT)3 phosphorylation in TNF- α -stimulated HPDLC. Furthermore, berteroin increased the expression of the antioxidant enzymes, heme oxygenase (HO)-1 and NAD(P)H quinone dehydrogenase (NQO)1, in IL-1 ß or TNF- α -stimulated HPDLCs. These results suggest that berteroin may decrease the production of inflammatory mediators in HPDLCs by suppressing the NF-κB pathway, and may also decrease the local reactive oxygen species (ROS) production in periodontal lesions by increasing the production of antioxidant enzymes.

Effects of erucin on inflammatory mediators and antioxidant enzymes' expression in TNF-α-stimulated human oral epithelial cells.

OBJECTIVES: Periodontitis is a chronic inflammatory disease induced by periodontal disease-causing bacteria. It has been shown that excessive immune response against bacteria is involved in periodontal tissue destruction including alveolar bone resorption. Erucin is a biologically active substance found in cruciferous plants such as arugula and is classified as an isothiocyanate. No previous studies have attempted to use erucin in the treatment of periodontitis, and there are no papers that have examined the effects of erucin on periodontal resident cells. The purpose of this study was to analyze the effects of erucin on the production of inflammatory and antioxidant mediators produced by tumor necrosis factor (TNF)-α-stimulated TR146 cells, an oral epithelial cell line, including its effects on signaling molecules. METHODS: Cytokine and chemokine levels were measured by ELISA. Protein expression in TR146 cells and activations of signal transduction pathway were determined by Western blotting. RESULTS: Our results indicate that erucin suppresses interleukin-6 and CXC-chemokine ligand 10 production and vascular cell adhesion molecule-1 expression in TNF-α-stimulated TR146 cells. In addition, erucin induced the production of the antioxidant enzymes, Heme Oxygenase-1 and NAD(P)H quinone dehydrogenase 1 in TR146 cells. Furthermore, erucin suppressed TNF-α-stimulated nuclear factor-κB, signal transducer and activator of transcription3, and phospho-70S6 Kinase-S6 ribosomal protein signaling pathways in TR146 cells. We have shown that erucin has anti-inflammatory effects on oral epithelial cells and also induces the production of antioxidant mediators. CONCLUSIONS: These results suggest that erucin may provide a new anti-inflammatory agent that can be used in the treatment of periodontitis.

The Anti-Inflammatory Effects of Iberin on TNF-α-Stimulated Human Oral Epithelial Cells: In Vitro Research.

Iberin is a bioactive chemical found in cruciferous plants that has been demonstrated to have anticancer properties. However, there have been no reports on its effects on periodontal resident cells, and many questions remain unanswered. The aim of this study was to examine whether iberin had anti-inflammatory effects on human oral epithelial cells, including influences on signal transduction pathway activation in TNF-α-στιµυλατεd χελλσ. Iberin inhibited the production of interleukin (IL)-6 and C-X-C motif chemokine ligand 10 (CXCL10), as well as the expression of vascular cell adhesion molecule (VCAM)-1, inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX)-2 in tumor necrosis factor (TNF)-α-stimulated TR146 cells, a human oral epithelial cell line. Moreover, iberin administration increased the expression of antioxidant signaling pathways, such as Heme Oxygenase (HO)-1 and NAD(P)H quinone dehydrogenase 1 (NQO1). Furthermore, we found that iberin could inhibit the activation of the nuclear factor (NF)-κB, signal transducer and activator of transcription (STAT)3, and p70S6 kinase (p70S6K)-S6 ribosomal protein (S6) pathways in TNF-α-stimulated TR146 cells. In conclusion, iberin reduced inflammatory mediator expression in human oral epithelial cells by preventing the activation of particular signal transduction pathways.

6-(Methylsulfinyl) Hexyl Isothiocyanate Inhibits IL-6 and CXCL10 Production in TNF-α-Stimulated Human Oral Epithelial Cells.

6-(Methylsulfinyl) hexyl isothiocyanate (6-MSITC) is a bioactive substance found in wasabi (Wasabia japonica) and has been reported to have some bioactive effects including anticancer and antioxidant effects. However, there are no reports on its effects on periodontal resident cells, and many points remain unclear. In this study, we aimed to investigate whether 6-MSITC exerts anti-inflammatory effects on human oral epithelial cells, including effects on signal transduction pathway activation. 6-MSITC inhibited interleukin (IL)-6 and C-X-C motif chemokine ligand 10 (CXCL10) production in TNF-α-stimulated TR146 cells, which are a human oral epithelial cell line. Moreover, we found that 6-MSITC could suppress signal transducer and activator of transcription (STAT)3, nuclear factor (NF)-κB, and p70S6 kinase (p70S6K)-S6 ribosomal protein (S6) pathways activation in TNF-α-stimulated TR146 cells. Furthermore, STAT3 and NF-κB inhibitors could suppress IL-6 and CXCL10 production in TNF-α-treated TR146 cells. In summary, 6-MSITC could decrease IL-6 and CXCL10 production in human oral epithelial cell by inhibiting STAT3 and NF-κB activation.

Nobiletin Decreases Inflammatory Mediator Expression in Tumor Necrosis Factor-Stimulated Human Periodontal Ligament Cells.

Nobiletin, a biologically active substance in the skin of citrus fruits, has been reported to be an effective anti-inflammatory, anticancer, and antimicrobial agent. In this study, we aimed to examine the anti-inflammatory effects of nobiletin on tumor necrosis factor- (TNF-) stimulated human periodontal ligament cells (HPDLCs). Our results demonstrated that nobiletin treatment could decrease the expressions of inflammatory cytokines (C-X-C motif chemokine ligand (CXCL)10, C-C motif chemokine ligand (CCL)2, and interleukin- (IL-) 8), matrix metalloproteinases (MMPs) (MMP1 and MMP3), and prostaglandin-endoperoxide synthase 2 (PTGS2) in TNF-stimulated HPDLCs. Moreover, we revealed that nobiletin could inhibit the activation of nuclear factor- (NF-) κB and protein kinase B (AKT1) pathways in TNF-stimulated HPDLCs. Furthermore, nobiletin treatment enhanced nuclear factor, erythroid 2 like 2 (NFE2L2) and heme oxygenase 1 (HMOX1) expressions in TNF-stimulated HPDLCs. In conclusion, these findings suggest that nobiletin can inhibit inflammatory responses in TNF-stimulated HPDLCs by inhibiting NF-κB and AKT1 activations and upregulating the NFE2L2 and HMOX1 expression.

Nobiletin Inhibits Inflammatory Reaction in Interleukin-1ß-Stimulated Human Periodontal Ligament Cells.

The immune response in periodontal lesions is involved in the progression of periodontal disease. Therefore, it is important to find a bioactive substance that has anti-inflammatory effects in periodontal lesions. This study aimed to examine if nobiletin, which is found in the peel of citrus fruits, could inhibit inflammatory responses in interleukin (IL)-1ß-stimulated human periodontal ligament cells (HPDLCs). The release of cytokines (IL-6, IL-8, CXCL10, CCL20, and CCL2) and matrix metalloproteinases (MMP-1 and MMP-3) was assessed by ELISA. The expression of cell adhesion molecules (ICAM-1and VCAM-1) and the activation of signal transduction pathways (nuclear factor (NF)-κB, mitogen-activated protein kinases (MAPKs) and protein kinase B (Akt)) in HPDLCs were detected by Western blot analysis. Our experiments revealed that nobiletin decreased the expression of inflammatory cytokines, cell adhesion molecules, and MMPs in IL-1ß-stimulated HPDLCs. Moreover, we revealed that nobiletin treatment could suppress the activation of the NF-κB, MAPKs, and Akt pathways. These findings indicate that nobiletin could inhibit inflammatory reactions in IL-1ß-stimulated HPDLCs by inhibiting multiple signal transduction pathways, including NF-κB, MAPKs, and Akt.

The Polymethoxy Flavonoid Sudachitin Inhibits Interleukin-1ß-Induced Inflammatory Mediator Production in Human Periodontal Ligament Cells.

Sudachitin, which is a polymethoxylated flavonoid found in the peel of Citrus sudachi, has some biological activities. However, the effect of sudachitin on periodontal resident cells is still uncertain. The aim of this study was to examine if sudachitin could decrease the expression of inflammatory mediators such as cytokines, chemokines, or matrix metalloproteinase (MMP) in interleukin- (IL-) 1ß-stimulated human periodontal ligament cells (HPDLC). Sudachitin inhibited IL-1ß-induced IL-6, IL-8, CXC chemokine ligand (CXCL)10, CC chemokine ligand (CCL)2, MMP-1, and MMP-3 production in HPDLC. On the other hand, tissue inhibitor of metalloproteinase- (TIMP-) 1 expression was increased by sudachitin treatment. Moreover, we found that the nuclear factor- (NF-) κB and protein kinase B (Akt) pathways in the IL-1ß-stimulated HPDLC were inhibited by sudachitin treatment. These findings indicate that sudachitin is able to reduce inflammatory mediator production in IL-1ß-stimulated HPDLC by inhibiting NF-κB and Akt pathways.

Carnosic acid inhibits inflammatory cytokines production in human periodontal ligament cells.

OBJECTIVES: Carnosic acid (CA), which is one of bioactive compounds from rosemary, has various biological activities. However, the effect of CA on periodontal ligament cells is still uncertain. The aim of this study was to examine the effects of CA on inflammatory cytokines production in human periodontal ligament cells. METHODS: Cytokine and chemokine levels were measured by ELISA. Activations of signal transduction pathway were determined by Western blotting. RESULTS: Treatment of CA decreased inflammatory cytokines such as interleukin (IL)-6, CXC chemokine ligand (CXCL)10, CC chemokine ligand (CCL)2, and CCL20 productions in IL-1ß or tumor necrosis factor (TNF)-α-stimulated human periodontal ligament cells in a dose-dependent manner. Moreover, we found that CA could suppress Jun-N-terminal kinase (JNK) pathway, nuclear factor (NF)-κB pathway and signal transducer and activator of transcription (STAT)3 pathway activation in IL-1ß or TNF-α-stimulated human periodontal ligament cells. CONCLUSION: The results of this study suggest that CA has anti-inflammatory effects in human periodontal ligament cells by inhibiting JNK, NF-κB and STAT3 pathways.

Sudachitin Inhibits Matrix Metalloproteinase-1 and -3 Production in Tumor Necrosis Factor-α-Stimulated Human Periodontal Ligament Cells.

Sudachitin, a polymethoxylated flavonoid found in the skin of Citrus sudachi, is a biologically active substance. The aim of this study was to examine whether sudachitin could be used to inhibit the expression of matrix metalloproteinase (MMP)-1 and MMP-3, which are involved in the destruction of periodontal tissues in periodontal lesions, in tumor necrosis factor (TNF)-α-stimulated human periodontal ligament cells (HPDLC). Sudachitin suppressed TNF-α-induced MMP-1 and MMP-3 production in HPDLC. On the other hand, it enhanced tissue inhibitor of metalloproteinase (TIMP)-1 expression. The level of Akt phosphorylation in the TNF-α-stimulated HPDLC was decreased by sudachitin treatment. Moreover, an Akt inhibitor reduced MMP-1 and MMP-3 production and increased TIMP-1 production. These findings indicate that sudachitin reduces MMP-1 and MMP-3 production in TNF-α-stimulated HPDLC by inhibiting the Akt pathway.

Carnosic Acid Inhibits CXCR3 Ligands Production in IL-27-Stimulated Human Oral Epithelial Cells.

Carnosic acid, which is a bioactive compound isolated from rosemary, has various pharmacological effects. However, the anti-inflammatory effect of carnosic acid on periodontitis is still unknown. The aim of this study was to investigate the effect of carnosic acid on CXC chemokine receptor 3 (CXCR3) ligands, which are involved in Th1 cells migration and accumulation, production in interleukin (IL)-27-stimulated human oral epithelial cells (TR146 cells). Carnosic acid decreased CXC chemokine ligand (CXCL)9, CXCL10, and CXCL11 production in IL-27-stimulated TR146 cells in a dose-dependent fashion. Moreover, we disclosed that carnosic acid could suppress signal transducer and activator of transcription (STAT)1, STAT3, and protein kinase B (Akt) phosphorylation in IL-27-stimulated TR146 cells. Furthermore, STAT1, STAT3, and Akt inhibitors could suppress CXCR3 ligands production in IL-27-treated TR146 cells. In summary, carnosic acid could reduce CXCR3 ligands production in human oral epithelial cell by inhibiting STAT1, STAT3, and Akt activation.

Interleukin (IL)-35 Suppresses IL-6 and IL-8 Production in IL-17A-Stimulated Human Periodontal Ligament Cells.

Interleukin (IL)-35 is a novel anti-inflammatory cytokine that is produced by regulatory T cells. IL-35 is reported to suppress IL-17A-producing helper T (Th17) cell activation. IL-17A is related to progression of periodontitis. Furthermore, IL-35 and IL-17A are detected in human gingival crevicular fluid. However, the effect of IL-35 and interaction between IL-35 and IL-17A on pro-inflammatory cytokine production in human periodontal resident cells are still unclear. The aim of this study was to clarify the effect of IL-35 on IL-6 and IL-8 production in human periodontal ligament cells (HPDLCs) stimulated with IL-17A. IL-35 inhibited IL-6 and IL-8 production in IL-17A-stimulated HPDLCs. Moreover, western blot analysis showed that IL-35 suppressed extracellular signal-regulated kinase (ERK) and nuclear factor (NF)-κB p65 phosphorylation in IL-17A-stimulated HPDLCs. Our findings suggested that IL-35 produced from regulatory T cells might inhibit progression of periodontitis by decreasing IL-17A-induced levels of IL-6 and IL-8.

Transforming growth factor-ß1 increases C-C chemokine ligand 11 production in interleukin 4-stimulated human periodontal ligament cells.

Transforming growth factor (TGF)-ß1 is a multifunctional cytokine, which can control certain functions of various kinds of cells. However, it is unclear whether TGF-ß1 affects T-cell migration in periodontal lesions. The aim of this study was to examine the effects of TGF-ß1 on the production of C-C chemokine ligand (CCL)11, which is a T-helper 2-type chemokine, in human periodontal ligament cells (HPDLC). Interleukin (IL)-4 induced CCL11 production, but TGF-ß1 did not, in HPDLC. However, TGF-ß1 enhanced CCL11 production in IL-4-stimulated HPDLC. Western blot analysis showed that the signal transducer and activator of transcription 6 (STAT6) pathway was highly activated in HPDLC that had been stimulated with both IL-4 and TGF-ß1. Mitogen-activated protein kinase activation did not differ between the HPDLC treated with a combination of IL-4 and TGF-ß1 and those treated with IL-4 or TGF-ß1 alone. Moreover, a STAT6 inhibitor significantly inhibited CCL11 production in HPDLC that had been stimulated with IL-4 and TGF-ß1. The current study clearly demonstrated that TGF-ß1 enhanced IL-4-induced CCL11 production in HPDLC. The STAT6 pathway is important for CCL11 production in IL-4- and TGF-ß1-treated HPDLC.

Honokiol and Magnolol Inhibit CXCL10 and CXCL11 Production in IL-27-Stimulated Human Oral Epithelial Cells.

Honokiol and magnolol, which are lignans isolated from Magnolia quinquepeta, have some pharmacological effects. However, the anti-inflammatory effects of honokiol and magnolol on periodontal disease are still uncertain. The aim of this study was to examine the effect of honokiol and magnolol on CXC chemokine receptor 3 (CXCR3) ligands, which are related with Th1 cell migration, production in interleukin (IL)-27-stimulated human oral epithelial cells (TR146 cells). Honokiol and magnolol inhibited CXC chemokine ligand (CXCL)10 and CXCL11 production in IL-27-stimulated TR146 cells in a dose-dependent manner. Moreover, we revealed that honokiol and magnolol could suppress signal transducer and activator of transcription (STAT)3 and protein kinase B (Akt) phosphorylation in IL-27-stimulated TR146 cells though STAT1 phosphorylation was not suppressed by honokiol and magnolol treatment. Furthermore, STAT3 and Akt inhibitors could suppress CXCR3 ligand production in TR146 cells. In summary, honokiol and magnolol could reduce CXCR3 ligand production in oral epithelial cell by inhibiting STAT3 and Akt activation.

IL-27 Modulates Chemokine Production in TNF-α -Stimulated Human Oral Epithelial Cells.

BACKGROUND/AIMS: Interleukin-27 (IL-27) is a cytokine which belongs to the IL-12 family. However, the role of IL-27 in the pathogenesis of periodontal disease is uncertain. The aim of this study was to examine the effect of IL-27 on chemokine production in TNF-α-stimulated human oral epithelial cells (TR146). METHODS: We measured chemokine production in TR146 by ELISA. We used western blot analysis to detect the phosphorylation levels of signal transduction molecules, including STAT1 and STAT3 in TR146. We used inhibitors to examine the role of STAT1 and STAT3 activation. RESULTS: IL-27 increased CXCR3 ligands production in TNF-α-stimulated TR146. Meanwhile, IL-27 suppressed IL-8 and CCL20 production induced by TNF-α. STAT1 phosphorylation level in IL-27 and TNF-α-stimulated TR146 was enhanced in comparison to TNF-α-stimulated TR146. STAT3 phosphorylation level in IL-27-treated TR146 did not change by TNF-α. Both STAT1 inhibitor and STAT3 inhibitor decreased CXCR3 ligands production. STAT1 inhibitor overrode the inhibitory effect of IL-27 on IL-8 and CCL20 production in TNF-α-stimulated TR146. Meanwhile, STAT3 inhibitor did not modulate IL-8 and CCL20 production. CONCLUSION: IL-27 might control leukocyte migration in periodontal lesion by modulating chemokine production from epithelial cells.

IL-29 Enhances CXCL10 Production in TNF-α-stimulated Human Oral Epithelial Cells.

Interleukin-29 (IL-29) is a cytokine belonging to the Type III interferon family. It was recently detected in the gingival crevicular fluid of periodontitis patients. However, the role of IL-29 in the pathogenesis of periodontal disease remains unknown. The aim of this study was to examine the effects of IL-29 on C-X-C motif chemokine ligand 10 (CXCL10) production in human oral epithelial cells. We measured CXCL10 production in TR146 cells, which is a human oral epithelial cell line, using an enzyme-linked immunosorbent assay. We used a Western blot analysis to detect IL-29 receptor expression and the phosphorylation levels of signal transduction molecules, including p38 mitogen-activated protein kinases (MAPK), signal transducer and activator of transcription 3 (STAT3), and nuclear factor (NF)- κB p65, in the TR146 cells. The TR146 cells expressed the IL-29 receptor. IL-29 induced CXCL10 production in the TR146 cells. IL-29 significantly enhanced CXCL10 production in tumor necrosis factor (TNF)-α-stimulated TR146 cells. The p38 MAPK, STAT3, and NF-κB pathways were found to be related to the IL-29-induced enhancement of CXCL10 production in TNF-α-stimulated TR146 cells. IL-29 promotes T helper 1-cell accumulation in periodontal lesions by inducing CXCL10 production in oral epithelial cells.

Gomisin N Decreases Inflammatory Cytokine Production in Human Periodontal Ligament Cells.

Gomisin N, which is a lignan isolated from Schisandra chinensis, has some pharmacological effects. However, the anti-inflammatory effects of gomisin N on periodontal disease are uncertain. The aim of this study was to examine the effect of gomisin N on inflammatory mediator production in tumor necrosis factor (TNF)-α-stimulated human periodontal ligament cells (HPDLC). Gomisin N inhibited interleukin (IL)-6, IL-8, CC chemokine ligand (CCL) 2, and CCL20 production in TNF-α-stimulated HPDLC in a dose-dependent manner. Moreover, we revealed that gomisin N could suppress extracellular signal-regulated kinase (ERK) and c-Jun N terminal kinase (JNK) phosphorylation in TNF-α-stimulated HPDLC though protein kinase B (Akt) phosphorylation was not suppressed by gomisin N treatment. In summary, gomisin N might exert anti-inflammatory effects by attenuating cytokine production in periodontal ligament cells via inhibiting the TNF-α-stimulated ERK and JNK pathways activation.

Alkannin inhibits CCL3 and CCL5 production in human periodontal ligament cells.

Alkannin, which is found in Alkanna tinctoria, a member of the borage family, is used as a food coloring. Alkannin has recently been reported to have certain biological functions, such as anti-microbial and anti-oxidant effects. It is known that CC chemokine receptor (CCR) 5-positive leukocytes contribute to alveolar bone resorption in periodontal lesions. The aim of this study was to examine whether alkannin inhibits the production of CC chemokine ligand (CCL) 3 and CCL5, which are CCR5 ligands, in human periodontal ligament cells (HPDLC). Interleukin (IL)-1ß induced CCL3 and CCL5 production in HPDLC. Alkannin inhibited IL-1ß-mediated CCL3 and CCL5 production in HPDLC in a dose-dependent manner. Moreover, we revealed that alkannin suppressed inhibitor of kappa B-α degradation in IL-1ß-stimulated HPDLC. In addition, a nuclear factor (NF)-κB inhibitor significantly inhibited CCL3 and CCL5 production in IL-1ß-stimulated HPDLC. These results demonstrate that alkannin inhibits CCR5 ligand production in IL-1ß-stimulated HPDLC by attenuating the NF-κB signaling pathway.

Melatonin Inhibits CXCL10 and MMP-1 Production in IL-1ß-Stimulated Human Periodontal Ligament Cells.

Melatonin is a hormone that is mainly secreted by the pineal gland and exhibits a wide spectrum of activities, including antioxidant functions. Melatonin has been detected in gingival crevicular fluid. However, the role of melatonin in periodontal tissue is still uncertain. The aim of this study was to examine the effects of melatonin on inflammatory mediator expression in human periodontal ligament cells (HPDLC). Interleukin (IL)-1ß induced CXC chemokine ligand (CXCL)10, matrix metalloproteinase (MMP)-1, and tissue inhibitors of metalloproteinase (TIMP)-1 production in HPDLC. Melatonin decreased CXCL10 and MMP-1 production and increased TIMP-1 production in IL-1ß-stimulated HPDLC. Western blot analysis showed that melatonin inhibited p38 mitogen-activated protein kinase (MAPK) and c-jun N-terminal kinase (JNK) phosphorylation, and IkB-α degradation and phosphorylation in IL-1ß-stimulated HPDLC. These results suggest that melatonin might inhibit Th1 cell migration by reducing CXCL10 production. Moreover, melatonin might inhibit soft tissue destruction by decreasing MMP-1 production in periodontal lesions.