Transcriptome Analysis of Porphyromonas gingivalis Lipopolysaccharide-Induced Early Gene Expression in Human Gingival Keratinocytes.

Aim: Porphyromonas gingivalis lipopolysaccharide (PgLPS) is a significant virulence factor and a driver of early innate immune responses in epithelial cells. The presence of PgLPS in immediate proximity to gingival epithelium induces significant inflammatory responses. In primary human gingival keratinocytes (HGK), we utilized transcriptome analysis to elucidate the change in early gene expression induced by PgLPS.

Monoamine Oxidase-B Inhibitor Reduction in Pro-Inflammatory Cytokines Mediated by Inhibition of cAMP-PKA/EPAC Signaling.

Mucosal epithelial cell integrity is an important component of innate immunity and it protects the host from an environment rich in microorganisms. Virulence factors from Gram-negative bacteria [e.g.

Monoamine Oxidase Inhibitors: A Review of Their Anti-Inflammatory Therapeutic Potential and Mechanisms of Action.

Chronic inflammatory diseases are debilitating, affect patients' quality of life, and are a significant financial burden on health care. Inflammation is regulated by pro-inflammatory cytokines and chemokines that are expressed by immune and non-immune cells, and their expression is highly controlled, both spatially and temporally. Their dysregulation is a hallmark of chronic inflammatory and autoimmune diseases.

Development of Novel Monoamine Oxidase-B (MAO-B) Inhibitors with Reduced Blood-Brain Barrier Permeability for the Potential Management of Noncentral Nervous System (CNS) Diseases.

Studies indicate that MAO-B is induced in peripheral inflammatory diseases. To target peripheral tissues using MAO-B inhibitors that do not permeate the blood-brain barrier (BBB) the MAO-B-selective inhibitor deprenyl was remodeled by replacing the terminal acetylene with a COH function, and incorporating a para-OCHAr motif (compounds 10a-s). Further, in compound 32 the C-2 side chain corresponded to CHCN.

Lipopolysaccharide induces a stromal-epithelial signalling axis in a rat model of chronic periodontitis.

Aim: Lipopolysaccharide is a bacterial virulence factor implicated in chronic periodontitis, which may penetrate the junctional epithelial barrier and basement membrane to insult underlying stroma. We sought to identify lipopolysaccharide-induced global gene expression changes responsible for signalling between stroma and epithelium during disease onset.

Materials And Methods: Using a rat lipopolysaccharide periodontitis model, junctional epithelium and underlying stromal tissue were separately collected from healthy and diseased animals by laser-capture microdissection and subject to gene expression microarray analysis.

Craniofacial defect regeneration using engineered bone marrow mesenchymal stromal cells.

Large craniofacial bony defects remain a significant clinical challenge. Bone marrow mesenchymal stromal cells (BM-MSCs) constitute a multipotent population. Previously, we developed a novel approach for BM-MSC expansion on 3D CultiSpher-S gelatin microcarrier beads in spin culture with preservation of their multipotentiality, reduction of apoptosis, and enhancement of bone formation in vivo.

Periodontal regeneration using engineered bone marrow mesenchymal stromal cells.

Regeneration of lost periodontium is a challenge in that both hard (alveolar bone, cementum) and soft (periodontal ligament) connective tissues need to be restored to their original architecture. Bone marrow mesenchymal stromal cells (BM-MSCs) appear to be an attractive candidate for connective tissue regeneration. We hypothesized that BM-MSCs are able to sense biological cues from the local microenvironment and organize appropriately to contribute to the regeneration of both soft and hard periodontal connective tissues.

Lipopolysaccharide-induced epithelial monoamine oxidase mediates alveolar bone loss in a rat chronic wound model.

Reactive oxygen species (ROS) production is an antimicrobial response to pathogenic challenge that may, in the case of persistent infection, have deleterious effects on the tissue of origin. A rat periodontal disease model was used to study ROS-induced chronic epithelial inflammation and bone loss. Lipopolysaccharide (LPS) was applied for 8 weeks into the gingival sulcus, and histological analysis confirmed the onset of chronic disease.

An in vitro analysis of mechanical wounding-induced ligand-independent KGFR activation.

Background: KGFR (keratinocyte growth factor receptor), exclusively expressed in epithelial cells, plays an important role in wound healing. However, mechanisms of KGFR activation and signaling in wound healing are not clearly understood.

Objectives: We utilized an in vitro mechanical wounding model to examine ligand-independent KGFR activation, its regulation by reactive oxygen species (ROS) and the functional significance of this activation mechanism.

Mechanical induction of an epithelial cell chymase associated with wound edge migration.

Chymase is a chymotrypsin-like serine protease predominantly produced by mast cells. In this study, human cutaneous and gingival keratinocytes, ovary surface epithelia, and a porcine epithelial cell line were assayed by homology-based cloning, and the amplified DNA fragment was identified as a chymase. In vitro, chymase could not be induced by serum or cytokine treatment alone.

Absence of alphavbeta6 integrin is linked to initiation and progression of periodontal disease.

Integrin alphavbeta6 is generally not expressed in adult epithelia but is induced in wound healing, cancer, and certain fibrotic disorders. Despite this generalized absence, we observed that alphavbeta6 integrin is constitutively expressed in the healthy junctional epithelium linking the gingiva to tooth enamel. Moreover, expression of alphavbeta6 integrin was down-regulated in human periodontal disease, a common medical condition causing tooth loss and also contributing to the development of cardiovascular diseases by increasing the total systemic inflammatory burden.

Ex vivo expansion of rat bone marrow mesenchymal stromal cells on microcarrier beads in spin culture.

Bone marrow mesenchymal stromal cells (BM-MSC) are attractive candidates for connective tissue regeneration. Currently, their use is limited by poor overall cell survival and high apoptosis rates upon transplantation in vivo. We hypothesized that disruption of cell-extracellular matrix contact either during cell expansion or immediately prior to cell transplantation may impair cell viability and facilitate apoptosis.

RNA integrity and in situ RT-PCR in dento-alveolar tissues after microwave accelerated demineralisation.

Objective: The structural organization of oral soft tissue and its relationship with highly calcified teeth are difficult to preserve unless tissues are decalcified, paraffin embedded and subsequently sectioned. However, enamel decalcification time and its negative impact on RNA integrity makes it difficult to effectively analyse in situ gene expression. This study examined the impact of microwave-enhanced decalcification on processing time, RNA integrity and detection of in situ mRNA expression in hard and soft tissue for cell type specific markers of Keratinocyte growth factor receptor, Scleraxis and Osteonectin.

Keratinocyte growth factor-1 expression in healthy and diseased human periodontal tissues.

Objectives: Keratinocyte growth factor-1 (KGF-1) is up-regulated in chronic inflammation and specifically stimulates epithelial cell proliferation by signaling through the epithelial-specific keratinocyte growth factor receptor (KGFR). We examined KGF-1 and KGFR protein and gene expression in healthy and diseased periodontal tissues.

Methods: Tissues were collected from patients with periodontal health or disease, immediately frozen and stained for KGF-1 and KGFR protein expression.

Fusobacterium nucleatum increases collagenase 3 production and migration of epithelial cells.

Fusobacterium nucleatum is closely associated with human periodontal diseases and may also be a causative agent in other infections, such as pericarditis, septic arthritis, and abscesses of tonsils and liver. Initiation and outcome of infective diseases depend critically on the host cell signaling system altered by the microbe. Production of proteinases by infected cells is an important factor in pericellular tissue destruction and cell migration.

Keratinocyte growth factor 1 inhibits wound edge epithelial cell apoptosis in vitro.

The ability of keratinocyte growth factor 1 to modulate apoptosis in the absence of proliferation was studied in vitro. A HaCaT scrape wound model was developed in which dense monolayers prior to wounding were cultured to quiescence in defined media with hydroxyurea at concentrations that blocked proliferation without loss of cell viability. Scrape wounding was then found to induce apoptosis, originating at the wound edge, but subsequently radiating away over a 24 h period to encompass areas not originally damaged.

Clinical and microbiologic study of periodontitis associated with Kindler syndrome.

Background: Little is known about the onset and prevalence of periodontal disease in patients with the rare Kindler syndrome, a genodermatological disorder. This study investigated the level of clinical periodontal attachment in relation to age and presence of putative periodontopathogenic bacteria in individuals with Kindler syndrome.

Methods: Eighteen individuals diagnosed with Kindler syndrome and 13 control subjects, aged 4 to 37 years, from rural Panama received a limited clinical periodontal examination.

Induction of keratinocyte growth factor 1 Expression by lipopolysaccharide is regulated by CD-14 and toll-like receptors 2 and 4.

Periodontal disease is a chronic inflammatory condition that is associated with increased concentrations of gram-negative pathogenic bacteria and epithelial cell proliferation. Regulation of this proliferation is poorly understood but is most likely controlled by locally expressed growth factors. Keratinocyte growth factor 1, an epithelium-specific growth factor, is expressed by gingival fibroblasts, and its expression is regulated in a concentration-dependent manner by lipopolysaccharide.

Keratinocyte growth factor (KGF)-1 and -2 protein and gene expression in human gingival fibroblasts.

The onset and progression of periodontal disease is associated with significant changes in the epithelial component of the attachment complex. From the early to the advanced stages of periodontal disease increased epithelial cell proliferation, migration and invasion into the surrounding connective tissue takes place. Concomitantly there is a significant increase in proinflammatory cytokine expression in periodontal tissue and quantitative and qualitative changes in the subgingival microflora, including an increase in gram-negative microorganisms.