Enhancement of lipopolysaccharide-stimulated PGE2 and IL-1 beta productionin gingival fibroblast cells from old rats

The effect of aging on gingival fibroblasts in response to bacterial infect ion was studied. Rat gingival fibroblast (rGF) cells were cultured from gin gival tissue removed from young (6 weeks old) and old (20 months old) rats. Both types of rGF cells were challenged with lipopolysaccharide (LPS) from the periodontal pathogen Campylobacter rectus. The levels of prostaglandin E-2 (PGE2) and interleukin 1 beta (IL-1 beta) released into the cultured m edium were measured by a specific radioimmunoassay. LPS stimulated PGE2 and IL-1 beta production in a dose- and time-dependent manner in rGF cells fro m both young and old rats was seen. Production of PGE2 and IL-1 beta by rGF cells from the old rats was higher than those from the young in response t o LPS. This greater ability from the older rGF cells to produce PGE2 and IL -1 beta was due to higher mRNA levels of cyclooxygenase 2 and IL-1 beta, re spectively. In contrast, cyclooxygenase-1 and IL-1 beta converting enzyme g ene mRNA levels remained unchanged. Because LPS-stimulated PGE2 and IL-1 be ta production was enhanced by in vivo cellular aging, aging of GF may affec t the severity of inflammation and bone resorption by producing a large amo unt of PGE2 and IL-1 beta in response to bacterial infection. (C) 1999 Else vier Science Inc. All rights reserved.