Analysis of cellular senescence in gingival tissues and gingival fibroblast cultures

Abstract

Senescence in periodontal tissues may be involved in the pathogenesis of periodontitis. In this study, we analyzed cellular senescence in gingival tissues of aged mice and in gingival fibroblast cultures and investigated the relationship of cellular senescence with the pathogenesis of periodontal disease. The proportions of senescence-associated β-galactosidase (SA-β-gal)-positive cells and the mRNA expression levels of p16 and p21 in gingival tissues and gingival fibroblasts from 20-month-old mice were significantly higher than those in gingival tissues and gingival fibroblasts from 10-week-old mice. The mRNA expression levels of IL-1β and TNF-α as well as the numbers of total macrophages and M1 macrophages were increased in gingival tissues of aged mice. Expression of these senescence-associated molecules was also increased in long-term passaged or hydrogen peroxide-stimulated human gingival fibroblasts; however, it was significantly suppressed by treatment with the senolytic drug ABT-263. These results suggest that cellular senescence can be induced in gingival fibroblasts in culture as was observed in gingival tissues of aged mice. An increase in senescent cells in the gingiva may be associated with the pathogenesis of periodontitis in part through activating an inflammatory response in periodontal tissues.

Expression of Senescence-Associated Secretory Phenotype in Senescent Gingival Fibroblasts

“…Oxidative stress has been reported to induce gingival fibroblast senescence and the effect of alveolar bone cell senescence on periodontal disease 13) . Kiyoshima et al…”