抄録
In the present study, we investigated the effects of a Kampo medicine Orento (TJ-120) on the production of prostaglandin E2 (PGE2), interleukin (IL)-6 and IL-8 by human gingival fibroblasts (HGFs) treated with lipopolysaccharide from Porphyromonas gingivalis (PgLPS). HGFs proliferation was dose-dependently decreased with Orento at days 3 and 7. However, treatment with PgLPS (10 ng/ml), Orento (up to 1 mg/ml) and their combinations for 24 h did not affect the viability of HGFs. Orento suppressed PgLPS-induced PGE2 production in a dose-dependent manner but did not alter basal PGE2 level. In contrast, Orento did not alter PgLPS-induced IL-6 and IL-8 productions. These alterations by Orento were similar to those by a mitogen-activated protein kinase kinase (MAPKK/MEK) inhibitor, PD98059. A Orento showed no effect on cyclooxygenase (COX)-1 and COX-2 activities, and increased cytoplasmic phospholipase A2 (cPLA2) expression and increased PgLPS-induced COX-2 expression. Orento suppressed PgLPS-induced mobility retardation of cPLA2 band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels, that is cPLA2 phosphorylation and its activation, while Orento alone did not alter cPLA2 phosphorylation. Orento suppressed PgLPS-induced extracellular signal-regulated kinase (ERK) phosphorylation, which is known to lead to ERK activation and cPLA2 phosphorylation. These results suggest that Orento decreased PGE2 production by inhibition of cPLA2 phosphorylation and its activation via inhibition of ERK phosphorylation, and also that Orento may be useful to improve gingival inflammation in periodontal disease.
