Oxidative Stress Induces Senescence In Gingival Fibroblasts.

Objectives: Oxidative damage is a frequent event that may occur in inflammatory conditions like periodontal disease. However, the precise effect of oxidative stress in gingival connective tissue cells is still not well defined. In the present study we evaluated the effect of oxidative stress, induced by hydrogen peroxide, on cell proliferation, DNA damage and cell size in human gingival fibroblasts (HGF).
Methods: HGF were obtained from two young donors and cells were exposed to an acute exposures of 500 uM hydrogen peroxide. Changes in cell size, cell proliferation and DNA damage were evaluated by immunofluorescence for actin, Ki67 and H2A.x respectively. Paired student’s “t” test was used to compare between conditions under study.
Results: Oxidative stress induced a significant increase in cell size, phosphorylated H2A.x and a reduction is cell proliferation. Both cell strains equally responded to the oxidative stimulus.
Conclusions: These changes are compatible with the induction of senescence in gingival connective tissue cells. Oxidative damage, a frequent event in inflammatory conditions, may induce senescence in fibroblasts. Further studies are needed to determine the magnitude of this senescence response in vivo.