Association of interleukin-1-induced, NF kappa B DNA-binding activity with collagenase gene expression in human gingival fibroblasts

Transcriptome Sequencing of Gingival Tissues from Impacted Third Molars Patients Reveals the Alterations of Gene Expression

OBJECTIVE

The removal of impacted third molars by surgery may occur with a series of complications, whereas limited information about the postoperative pathogenesis is available. The objective of this study is to identify changes in gene expression after flap surgical removal of impacted third molars and provide potential information to reduce postoperative complications.

METHODS

The gingival tissues of twenty patients with flap surgical removal of impacted third molars and twenty healthy volunteers were collected for gene expression testing. The collected gingival tissues were used RNA sequencing technology and quantitative real-time PCR validation was performed. DEG was mapped to protein databases such as GO and KEGG for functional annotation and, based on annotation information, for mining of differential expression genes in patients with mpacted third molars.

RESULTS

A total of 555 genes were differentially expressed. Among the top up-regulated genes, HLA-DRB4, CCL20, and CXCL8 were strongly associated with immune response and signal transduction. Among the top down-regulated genes, SPRR2B, CLDN17, LCE3D and LCE3E were related to keratinocyte differentiation, IFITM5, and BGLAP were related to bone mineralization, UGT2B17 is associated with susceptibility to osteoporosis. KEGG results showed that the DEGs were related to multiple disease-related pathways.

CONCLUSION

This first transcriptome analysis of gingival tissues from patients with surgical removal of impacted third molars provides new insights into postoperative genetic changes. The results may establish a basis for future research on minimizing the incidence of complications after flap-treated third molars.

NF-κB signaling and crosstalk during carcinogenesis

Transcription factors (TFs) are proteins that control the transcription of genetic information from DNA to mRNA by binding to specific DNA sequences either on their own or with other proteins as a complex. TFs thus support or suppress the recruitment of the corresponding RNA polymerase. In general, TFs are classified by structure or function. The TF, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), is expressed in all cell types and tissues. NF-κB signaling and crosstalk are involved in several steps of carcinogenesis including in sequences involving pathogenic stimulus, chronic inflammation, fibrosis, establishment of its remodeling to the precancerous niche (PCN) and transition of a normal cell to a cancer cell. Triggered by various inflammatory cytokines, NF-κB is activated along with other TFs with subsequent stimulation of cell proliferation and inhibition of apoptosis. The involvement of NF-κB in carcinogenesis provides an opportunity to develop anti-NF-κB therapies. The complexity of these interactions requires that we elucidate those aspects of NF-κB interactions that play a role in carcinogenesis, the sequence of events leading to cancer.

Effects of Positive Pressure in Odontogenic Keratocysts

Intracystic fluid pressure is thought to be involved in odontogenic cyst growth. In this study, we investigated the effects of positive pressure on the expression of interleukin-1α (IL-1α), matrix metalloproteinases (MMPs), and prostaglandin E2 (PGE2) in odontogenic keratocysts to determine whether this pressure stimulates inflammatory cytokine production and signaling of osteoclastogenic events. Positive pressure enhanced the expression of IL-1α mRNA and protein in odontogenic keratocyst epithelial cells, and increased the secretion of MMP-1, MMP-2, MMP-3, and PGE2 in a co-culture of odontogenic keratocyst fibroblasts and the epithelial cells. The pressure-induced secretions were inhibited by an interleukin-1 receptor antagonist. Recombinant human interleukin-1α (rhIL-1α) increased the secretion of MMP-1, MMP-2, MMP-3, and PGE2 in the fibroblasts. Furthermore, in the fibroblasts, rhIL-1α enhanced the expression of macrophage colony-stimulating factor (M-CSF) mRNA, and rhIL-1α-induced PGE2 increased the expression of nuclear factor κB ligand (RANKL) mRNA. Thus, positive pressure may play a crucial role in odontogenic keratocyst growth via stimulating the expression of IL-1α in epithelial cells.

MAPKs, activator protein-1 and nuclear factor-κB mediate production of interleukin-1β-stimulated cytokines, prostaglandin E₂ and MMP-1 in human periodontal ligament cells

BACKGROUND AND OBJECTIVE

Determination of the interleukin-1 (IL-1) signaling cascades that lead to the production of various inflammatory mediators and catabolic factors may clarify attractive targets for therapeutic intervention for periodontitis. We comprehensively assessed the involvement of MAPKs, activator protein-1 (AP-1) and nuclear factor-κB (NF-κB) in IL-1β-induced production of interleukin-6 (IL-6), interleukin-8 (IL-8), prostaglandin E(2) (PGE(2) ) and MMP-1 in human periodontal ligament cells.

MATERIAL AND METHODS

Human periodontal ligament cells were pretreated with an inhibitor for each of the MAPKs or NF-κB and subsequently treated with IL-1β. Following treatment, phosphorylation of three types of MAPK (ERK, p38 MAPK and c-Jun N-terminal kinase), IκB kinase (IKK) α/β/γ and IκB-α, as well as the DNA binding activity of AP-1 and NF-κB and the production of IL-6, IL-8, PGE(2) and MMP-1, were determined by western blotting, a gel mobility shift assay and ELISA, respectively.

RESULTS

The three MAPKs, simultaneously activated by IL-1β, mediated the subsequent DNA binding of AP-1 at various magnitudes, while IKKα/β/γ, IκB-α and NF-κB were also involved in the IL-1 signaling cascade. Furthermore, IL-1β stimulated the production of IL-6, IL-8, PGE(2) and MMP-1 via activation of the three MAPKs and NF-κB, because inhibitors of these significantly suppressed the IL-1β-stimulated production of these factors.

CONCLUSION

Our results strongly suggest that MAPK, AP-1 and NF-κB mediate the IL-1β-stimulated synthesis of IL-6, IL-8, PGE(2) and MMP-1 in human periodontal ligament cells. Therefore, inhibition of activation of MAPK, AP-1 and/or NF-κB may lead to therapeutic effects on progression of periodontitis.

Interleukin-1 stimulates cytokines, prostaglandin E2 and matrix metalloproteinase-1 production via activation of MAPK/AP-1 and NF-kappaB in human gingival fibroblasts

Interleukin-1 (IL-1) plays a crucial role in the immunopathological responses involved with tissue destruction in chronic inflammatory diseases, such as periodontal disease, as it stimulates host cells including fibroblasts to produce various inflammatory mediators and catabolic factors. We comprehensively investigated the involvement of mitogen-activated protein kinases (MAPKs)/activator protein-1 (AP-1) and IkappaB kinases (IKKs)/IkappaBs/nuclear factor-kappaB (NF-kappaB) in IL-1beta-stimulated IL-6, IL-8, prostaglandin E(2) (PGE(2)) and matrix metalloproteinase-1 (MMP-1) production by human gingival fibroblasts (HGF). Three MAPKs, extracellular signal-regulated kinase (ERK), p38 MAPK and c-Jun N-terminal kinase (JNK), which were simultaneously activated by IL-1beta, mediated subsequent c-fos and c-jun mRNA expression and DNA binding of AP-1 at different magnitudes. IKKalpha/beta/IkappaB-alpha/NF-kappaB was also involved in the IL-1 signaling cascade. Further, IL-1beta stimulated HGF to produce IL-6, IL-8, PGE(2) and MMP-1 via activation of the 3 MAPKs and NF-kappaB, as inhibitors of each MAPK and NF-kappaB significantly suppressed the production of IL-1beta-stimulated factors, though these pathways might also play distinct roles in IL-1beta activities. Our results strongly suggest that the MAPKs/AP-1 and IKK/IkappaB/NF-kappaB cascades cooperatively mediate the IL-1beta-stimulated synthesis of IL-6, IL-8, PGE(2) and MMP-1 in HGF.

The effects of progesterone on matrix metalloproteinases in cultured human gingival fibroblasts

BACKGROUND

Although pregnancy gingivitis is widely believed to result from elevated hormone concentrations, the mechanism(s) involved in the etiology of this condition remain unknown. Paradoxically, despite the apparent inflammation for a prolonged period, pregnancy gingivitis rarely progresses to periodontitis and usually resolves postpartum. We used several methods to test in vitro the hypothesis that the elevated progesterone levels of pregnancy might inhibit the production of some of the matrix metalloproteinases (MMPs) that are responsible for periodontal destruction.

METHODS

Cultured human gingival fibroblasts (GF) were tested in phenol red-free, serum-free medium with or without the progestogen, medroxyprogesterone acetate (MPA; 10(-6) M), using interleukin-1beta (IL-1beta) to initiate immune responses and MMP production. These MMP responses were examined by macroarrays, reverse transcription-polymerase chain reaction (RT-PCR), zymograms, and enzyme-linked immunosorbent assay (ELISA).

RESULTS

Array analysis showed that pretreatment of GF with MPA reduced mRNA induction for MMPs-1, -3, and -10 in response to 6 to 8 hours incubation with IL-1beta. RT-PCR confirmed, that after 24 hours with IL-1beta , GF pretreated with MPA had undetectable levels of mRNA for MMPs-1, -2, -3, -7, -10, and -13. Zymograms of culture media from this 24-hour period showed reduction in several proteolytic activities. Examination of such 24-hour media using ELISA for MMP-3 and pro-MMP-13 confirmed that secretion of these enzymes was upregulated by IL-1beta and modulated downward by pretreatment with MPA.

CONCLUSIONS

Production by GF of numerous MMPs in response to IL-1beta was significantly reduced by progesterone. This steroidal modulation of proteolytic enzymes could help to explain why pregnancy gingivitis typically is not characterized by progression to periodontitis.

Marsupialization inhibits interleukin-1α expression and epithelial cell proliferation in odontogenic keratocysts

BACKGROUND

Marsupialization results in the reduction of odontogenic cyst size. Interleukin-1alpha (IL-1alpha) is thought to play a crucial role for the expansion of odontogenic keratocysts. The aim of this study was to investigate the effects of marsupialization on the expression of IL-1alpha and on the proliferating activity of a lining epithelium in odontogenic keratocysts.

METHODS

The concentrations of IL-1alpha, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in the intracystic fluids of odontogenic keratocysts were measured by the enzyme-linked immunosorbent assay (ELISA). The expression of IL-1alpha mRNA in odontogenic keratocysts was measured before and after marsupialization by in situ hybridization. The expression of IL-1alpha and epithelial cell-proliferating activities in odontogenic keratocysts were also measured by immunohistochemistry using antibodies for human IL-1alpha and Ki-67 antigen, respectively.

RESULTS

The intracystic fluid levels of IL-1alpha were significantly higher than those of IL-6 and TNF-alpha in odontogenic keratocysts. In situ hybridization and immunohistochemistry showed that strong expression of IL-1alpha mRNA and protein was mainly detected in the epithelial cells of odontogenic keratocysts. After marsupialization, the signal intensities for IL-1alpha mRNA and protein were significantly decreased. In addition, the Ki-67 labeling index of the epithelial cells was decreased proportionally with the grade of IL-1alpha mRNA expression after the marsupialization.

CONCLUSION

Our findings suggest that marsupialization may reduce the size of odontogenic keratocyst by inhibiting IL-1alpha expression and the epithelial cell proliferation.

Regulation of IL-1-induced gingival collagenase gene expression by activator protein-1 (c-Fos/c-Jun)

Matrix metalloproteinase-1 is probably involved in the progression of periodontal disease. The aim of this study was to investigate whether IL-1beta stimulates the expression of the activator protein 1 (AP-1) transcription factor and, consequently, if the AP-1 transcription factor participates in the regulation of collagenase gene expression in human gingival fibroblast cells. In this study, we demonstrate that the concentration of the protein components of AP-1 transcription factor, c-Fos and c-Jun, is enhanced by IL-1beta both at mRNA and protein levels, utilizing Northern blot analysis, electrophoretic mobility gel shift assay and Western blot analysis. The IL-1beta stimulated the collagenase-CAT and AP-1-CAT activities in a dose dependent manner with respect to the amount of DNA used in transfections. Further, overexpression of c-Fos and c-Jun proteins revealed a dose-dependent transcriptional activation of the collagenase promoter. These findings, coupled with the existence of AP-1 consensus DNA binding sites on the collagenase gene promoter, show that regulation of collagenase gene expression by IL-1beta involves the transcription factor AP-1 in gingival fibroblasts.

Interleukin-1alpha-dependent regulation of matrix metalloproteinase-9(MMP-9) secretion and activation in the epithelial cells of odontogenic jaw cysts

Interleukin-1alpha (IL-1alpha) and matrix metalloproteinase-9 (MMP-9) are thought to be involved in odontogenic cyst expansion. In this study, we investigated the effects of IL-1alpha on the secretion and activation of MMP-9 in odontogenic jaw cysts. An active form of MMP-9 was present in odontogenic keratocyst (6 of 8 cases) fluids more frequently than dentigerous cyst (3 of 10 cases) and radicular cyst (3 of 10 cases) fluids, although proMMP-9 was present in all cyst fluids. Odontogenic keratocyst fragments in explant culture secreted a larger amount of IL-1alpha than dentigerous cyst and radicular cyst fragments in explant culture, and spontaneously secreted both proMMP-9 and an active form of MMP-9. The fragments of dentigerous cysts and radicular cysts secreted a small amount of proMMP-9, but no active form of MMP-9. Exogenously added recombinant human IL-1alpha (rhlL-1alpha) increased the secretion and activation of proMMP-9 in the fragments of dentigerous cysts and radicular cysts. The epithelial cells isolated from odontogenic keratocysts secreted IL-1alpha and proMMP-9 without stimulation. Under the cultivation on a fibronectin-coated dish, rhIL-1alpha increased the secretion of proMMP-9 from the epithelial cells in a dose-dependent manner. Moreover, rhIL-1alpha induced the secretion of proMMP-3 and plasminogen activator urokinase (u-PA) from the epithelial cells, and converted the secreted proMMP-3 to the active form in the presence of plasminogen. The secreted proMMP-9 was also activated in the presence of rhIL-1alpha and plasminogen. Hence, our results suggest that IL-1alpha may up-regulate not only proMMP-9 secretion but also proMMP-9 activation by inducing proMMP-3 and u-PA production in the cyst epithelial cells by autocrine/paracrine regulatory mechanisms.

Defining therapeutic targets by using adenovirus: blocking NF-kappaB inhibits both inflammatory and destructive mechanisms in rheumatoid synovium but spares anti-inflammatory mediators

The role of the transcription factor NF-kappaB in the pathogenesis of rheumatoid arthritis has long been a subject of controversy. We used an adenoviral technique of blocking NF-kappaB through overexpression of the inhibitory subunit IkappaBalpha, which has the advantage that it can be used in the diseased tissue itself, with >90% of the synovial macrophages, fibroblasts, and T cells infected. We found that the spontaneous production of tumor necrosis factor alpha and other pro-inflammatory cytokines is NF-kappaB-dependent in rheumatoid synovial tissue, in contrast to the main anti-inflammatory mediators, like IL-10 and -11, and the IL-1 receptor antagonist. Of even more interest, IkappaBalpha overexpression inhibited the production of matrix metalloproteinases 1 and 3 while not affecting their tissue inhibitor. Blocking NF-kappaB in the rheumatoid joint thus has a very beneficial profile, reducing both the inflammatory response and the tissue destruction. The adenoviral technique described here has widespread applicability, allowing rapid testing of the effects of blocking a potential therapeutic target in either cultures of normal cells or in the diseased tissue itself.

Paracrine stimulation of interstitial collagenase (MMP-1) in the human endometrium by interleukin 1alpha and its dual block by ovarian steroids

In the cycling human endometrium, the expression of interstitial collagenase (MMP-1) and of several related matrix metalloproteinases (MMPs) follows the late-secretory fall in sex steroid plasma concentrations and is thought to be a critical step leading to menstruation. The rapid and extensive lysis of interstitial matrix that precedes menstrual shedding requires a strict control of these proteinases. However, the mechanism by which ovarian steroids regulate endometrial MMPs remains unclear. We report here that, in the absence of ovarian steroids, MMP-1 expression in endometrial fibroblasts is markedly stimulated by medium conditioned by endometrial epithelial cells. This stimulation can be prevented by antibodies directed against interleukin 1alpha (IL-1alpha) but not against several other cytokines. Ovarian steroids inhibit the release of IL-1alpha and repress MMP-1 production by IL-1alpha-stimulated fibroblasts. In short-term cultures of endometrial explants obtained throughout the menstrual cycle, the release of both IL-1alpha and MMP-1 is essentially limited to the perimenstrual phase. We conclude that epithelium-derived IL-1alpha is the key paracrine inducer of MMP-1 in endometrial fibroblasts. However, MMP-1 production in the human endometrium is ultimately blocked by ovarian steroids, which act both upstream and downstream of IL-1alpha, thereby exerting an effective control via a "double-block" mechanism.