Effects of LL-37 on Gingival Fibroblasts: A Role in Periodontal Tissue Remodeling?

Mounting evidence suggests that the host defence peptide, LL-37, plays a role in both inflammation and in wound healing; however, the role of this peptide in the remodeling and maintenance of oral tissues is not yet fully understood. Fibroblasts are the most abundant cell type within the periodontal tissues, and gingival fibroblasts play an important role in maintaining and repairing the gingival tissues which are constantly exposed to external insults. In this study we examined the direct effects of LL-37 treatment on gingival fibroblasts and found that LL-37 significantly increased secretion of both interleukin 8 (IL-8) and IL-6 from these cells.

Characterisation of eppin function: expression and activity in the lung.

Eppin is a serine protease inhibitor expressed in male reproductive tissues.The aim of this study was to investigate the localisation and regulation of eppin expression in myeloid and epithelial cell lines, and explore its potential role as a multifunctional host defence protein.Using immunohistochemistry and Western blotting, eppin was detected in the lungs of patients with acute respiratory distress syndrome and cystic fibrosis lung disease.

Biodentine Reduces Tumor Necrosis Factor Alpha-induced TRPA1 Expression in Odontoblastlike Cells.

Introduction: The transient receptor potential (TRP) ion channels have emerged as important cellular sensors in both neuronal and non-neuronal cells, with TRPA1 playing a central role in nociception and neurogenic inflammation. The functionality of TRP channels has been shown to be modulated by inflammatory cytokines. The aim of this study was to investigate the effect of inflammation on odontoblast TRPA1 expression and to determine the effect of Biodentine (Septodent, Paris, France) on inflammatory-induced TRPA1 expression.

LL-37 in periodontal health and disease and its susceptibility to degradation by proteinases present in gingival crevicular fluid.

Aim: To determine the levels of LL-37 in and its susceptibility to degradation by components of gingival crevicular fluid (GCF) in periodontal health and disease.

Materials And Methods: Levels of LL-37 in GCF from periodontitis patients and periodontally healthy subjects were determined by ELISA. In addition, degradation of synthetic/exogenous LL-37 by components of GCF in the presence and absence of inhibitors was determined by matrix-assisted laser desorption/ionization time of flight mass spectrometry.

Evaluation of the ability of LL-37 to neutralise LPS in vitro and ex vivo.

Background: Human cathelicidin LL-37 is a cationic antimicrobial peptide (AMP) which possesses a variety of activities including the ability to neutralise endotoxin. In this study, we investigated the role of LPS neutralisation in mediating LL-37's ability to inhibit Pseudomonas aeruginosa LPS signalling in human monocytic cells.

Methodology/principal Findings: Pre-treatment of monocytes with LL-37 significantly inhibited LPS-induced IL-8 production and the signalling pathway of associated transcription factors such as NF-κB.

Periodontal disease in the older patient.

Unlabelled: Population projections predict an increasing number of dentate older people who will require assessment and treatment of periodontal disease. Studies show that healthy, older patients show no increased risk of periodontal disease progression compared to younger individuals, while periodontal treatment can be equally successful in the older age group. However, co-morbidity can impact negatively on both the periodontal tissues and the dentition.

Human odontoblasts express functional thermo-sensitive TRP channels: implications for dentin sensitivity.

Odontoblasts form the outermost cellular layer of the dental pulp where they have been proposed to act as sensory receptor cells. Despite this suggestion, evidence supporting their direct role in mediating thermo-sensation and nociception is lacking. Transient receptor potential (TRP) ion channels directly mediate nociceptive functions, but their functional expression in human odontoblasts has yet to be elucidated.

Neuropeptides regulate expression of angiogenic growth factors in human dental pulp fibroblasts.

Introduction: Neuropeptides play an important role in inflammation and repair and have been implicated in mediating angiogenesis. Pulp fibroblasts express neuropeptide receptors, and the aim of this research was to investigate whether neuropeptides could regulate angiogenic growth factor expression in vitro

Methods: An angiogenic array was used to determine the levels of 10 angiogenic growth factors expressed by human pulp fibroblasts.

Results: Pulp fibroblasts were shown to express angiogenin, angiopoietin-2, epidermal growth factor, basic fibroblast growth factor, heparin-binding epidermal growth factor, hepatocyte growth factor, leptin, platelet-derived growth factor, placental growth factor, and vascular endothelial growth factor.

Substance P expression by human dental pulp fibroblasts: a potential role in neurogenic inflammation.

Neurogenic inflammation describes the local release of neuropeptides, notably substance P (SP), from afferent neurons and might play a role in the pathogenesis of pulpal disease. The fibroblast is the most numerous cell type in the dental pulp, and recent work has suggested that it is involved in the inflammatory response. Primary pulp fibroblast cell populations were isolated by enzymatic digestion.

Regulation of HGF and SDF-1 expression by oral fibroblasts--implications for invasion of oral cancer.

Invasion and metastasis of oral squamous cell carcinoma (OSCC) is dependent on signals received from stromal fibroblasts present in the surrounding connective tissue. The aim of this study was to investigate the regulation of expression of two important signaling molecules--HGF and SDF-1--by both stromal fibroblasts and their 'activated' form, myofibroblasts, and to determine the role of these two factors in stimulating OSCC cell invasion in vitro. Fibroblasts and myofibroblasts produced similar levels of HGF and SDF-1.

Phenotypic differences between oral and skin fibroblasts in wound contraction and growth factor expression.

Wounds of the oral mucosa heal in an accelerated fashion with reduced scarring compared with cutaneous wounds. The differences in healing outcome between oral mucosa and skin could be because of phenotypic differences between the respective fibroblast populations. This study compared paired mucosal and dermal fibroblasts in terms of collagen gel contraction, alpha-smooth muscle actin expression (alpha-SMA), and production of the epithelial growth factors: keratinocyte growth factor (KGF) and hepatocyte growth factor/scatter factor (HGF).

The cytotoxic effects of human neutrophil peptide-1 (HNP1) and lactoferrin on oral squamous cell carcinoma (OSCC) in vitro.

Alpha-defensin or human neutrophil peptide-1 (HNP1) is a neutrophil-derived antimicrobial peptide with cytotoxic effects towards cancer cells. Lactoferrin is also stored in human neutrophils and is a glycoprotein involved in mediating cytotoxicity towards tumour cells. This study investigated the sensitivity of normal oral keratinocyte and oral squamous cell carcinoma (OSCC) cells to HNP1 and lactoferrin in various combinations.

Chlorhexidine-containing mucoadhesive polymeric compacts designed for use in the oral cavity: an examination of their physical properties, in vitro/in vivo drug release properties and clinical acceptability.

This study describes the formulation, physicochemical and mucoadhesive properties and in in vitro/in vivo release of chlorhexidine from mucoadhesive, polymeric compacts, designed for application within the oral cavity. Compacts were prepared by direct compression of mixtures containing 100 mg sodium carboxymethylcellulose (NaCMC), 25 mg hydroxyethylcellulose (HEC)/75 mg polyacrylic acid (PAA) and 75 mg HEC/25 mg PAA. The mechanical and mucoadhesive properties of the drug-loaded compacts were examined using a texture analyzer in compression and tension modes, respectively.

The effects of cyclosporin on the collagenolytic activity of gingival fibroblasts.

Background: The immunosuppressive agent cyclosporin is associated with a number of major side-effects including the development of gingival overgrowth. Although the pathogenesis of cyclosporin-induced gingival overgrowth remains unclear, it has been suggested that the finely regulated balance between extracellular matrix synthesis and degradation may be disturbed, resulting in an accumulation of excess connective tissue components within the gingival tissue. The aim of this study was to investigate the effect of cyclosporin on matrix metalloproteinases (MMP)-1 and tissue inhibitors of MMP (TIMP)-1 expression at the mRNA, protein, and enzyme activity levels.

The role of soluble interleukin (IL)-6 receptor in mediating the effects of IL-6 on matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 expression by gingival fibroblasts.

Background: Interleukin-6 (IL-6) is a multifunctional cytokine thought to play a role in the tissue destruction that characterizes periodontal disease. IL-6 exerts its cellular effects through a cell-surface receptor which also exists in a soluble form (sIL-6r). This study investigated the effects of IL-6 on matrix metalloproteinase (MMP)-1 activity in gingival fibroblast cultures, specifically determining the role of the sIL-6r in mediating these actions.