Measurements of eicosanoid and inflammatory cytokines in rats with spontaneous periodontal disease

Abstract

When periodontal disease develops, many inflammatory cells, mainly lymphocytes, are observed infiltrating the lesion. Chemokines such as MCP-1 and IL-8, which are produced by gingival epithelial cells undergoing stimulation by bacterial cell components from plaque bacteria through the toll-like receptor-2, are involved in the migration of these immunocompetent cells to the lesion site. It has been confirmed that the expression of these inflammatory cytokines is elevated in the gingival tissue and gingival sulcus exudates of periodontal disease patients. We investigated the dynamics of the inflammatory cytokines IL-1β, IL-6, TNF-α, IFN-γ, MCP-1 and anti-inflammatory cytokine IL-10 in rats with spontaneous periodontal disease (ODUS/Odu), an animal model of periodontal disease developed and maintained in our laboratory. In this study, we measured the plasma levels of the eicosanoid PGE_2 and inflammatory cytokines cytokine-induced neutrophil chemoattractant-1 (CINC-1), and the anti-inflammatory cytokine IL-4 in ODUS/Odu. Plasma cytokine levels were measured in these animals and in control rats (Res) at 0 (five weeks after birth), 1, 3, 6, 9 and 12 months after the start of the experiment using an enzyme-linked immunosorbent assay (ELISA) kit. The plasma levels of the eicosanoid PGE_2 and inflammatory cytokine CINC-1 were greater in ODUS/Odu than in Res throughout the experimental period. However, the plasma levels of the anti-inflammatory cytokine IL-4 was lower in ODUS/Odu than in Res. These results, similar to those obtained in patients with periodontal disease, suggest that the ODUS/Odu are a useful animal model of human periodontal disease.