Effects of Chronic Adult Periodontitis and Endotoxin (LPS) on Gingival Fibroblast Plasma Membrane Ca -Pump

Abstract

Gingival fibroblasts from patients with chronic adult periodontitis are known to produce cytokines in response to changing levels of bacterial lipopolysaccharide (LPS). Cytokine production is one of numerous cell processes that involve calcium dependent enzymes. It is possible that inflammation may induce changes in the amount of the Ca++-pump protein in gingival fibroblasts which could alter Ca++-dependent activities in these cells including the production and release of cytokines. The purpose of this study was to determine if differences exist in the amount of Ca++-pump protein in the gingival fibroblasts of periodontitis patients relative to control individuals without periodontal disease. Fibroblast explants from healthy tissue and from inflamed tissue from patients with chronic adult periodontitis, grown in culture, were analyzed for quantitative differences in the amount of Ca++-pump protein. Fibroblasts from chronic adult periodontitis patients exhibited significantly lower levels of Ca++-pump protein than fibroblasts from healthy subjects (p = 0.0015). However, fibroblasts from chronic adult periodontitis patients, when activated with LPS, did not exhibit significant differences in the amounts of Ca++-pump protein as compared to untreated controls (p = 0.2177). Similarly, cells from healthy subjects did not show significant reduction in Ca++-pump protein following activation with LPS (p = 0.1732). Our results suggest that plasma membrane Ca++-pump is significantly reduced in fibroblasts derived from patients with chronic periodontitis. However, factors other than LPS may be involved in the down-regulation of Ca+ -pump protein.