Dasatinib and Quercetin Limit Gingival Senescence, Inflammation, and Bone Loss

Abstract

Cellular senescence has emerged as one of the central hallmarks of aging and drivers of chronic comorbidities, including periodontal diseases. Senescence can also occur in younger tissues and instigate metabolic alterations and dysfunction, culminating in accelerated aging and pathological consequences. Senotherapeutics, such as the combination of dasatinib and quercetin (DQ), are being increasingly used to improve the clinical outcomes of chronic disorders and promote a healthy life span through the reduction of senescent cell burden and senescence-associated secretory phenotype (SASP). Recent evidence suggests that senescent cells and SASP can contribute to the pathogenesis of periodontal diseases as well. In this study, we investigated the effect of DQ interventions on periodontal tissue health using preclinical models of aging. In vitro, DQ ameliorated biological signatures of senescence in human gingival keratinocytes upon persistent exposure to periodontal bacteria, Fusobacterium nucleatum, by modulating the levels of key senescence markers such as p16, SA-β-galactosidase, and lamin-B1 and inflammatory mediators associated with SASP including interleukin-8, matrix metalloproteinase (MMP)-1, and MMP-3. In vivo, the oral administration of DQ mitigated senescent cell burden and SASP in gingival tissues and reduced naturally progressing periodontal bone loss in aged mice. Collectively, our findings provide proof-of-concept evidence for translational studies and reveal that targeting gingival senescence and the senescence-associated secretome can be an effective strategy to improve periodontal health, particularly in vulnerable populations.

Keywords: aging; metabolism; periodontal; senescence associated phenotype (SASP); senescent cell; senotherapy.

Figure 1.

Dasatinib and quercetin (DQ) reduces SA-β-galactosidase in gingival keratinocytes. (A) Representative images of SA-β-galactosidase–positive cells (in green) at 20× magnification. (B) Quantification of SA-β-galactosidase activity using an optical density of 600 nm. **P ≤ 0.01.

Figure 2.

Dasatinib and quercetin (DQ) reduces the senescence marker p16 in gingival keratinocytes. (A) Representative Western blots of p16 and (B) quantitative analysis. (C) Representative immunofluorescence images of p16-positive cells and (D) quantitative analysis. ****P ≤ 0.0001.

Figure 3.

Dasatinib and quercetin (DQ) attenuates nuclear envelope damage in gingival keratinocytes. (A) Representative Western blots of lamin-B1. (B) Relative protein levels of lamin-B1. (C) Representative immunofluorescence images of lamin-B1. (D) The percentage of cells exhibiting nuclear defects. ***P ≤ 0.001, ****P ≤ 0.0001.

Figure 4.

Dasatinib and quercetin (DQ) mitigates inflammatory mediators related to senescence secretome in gingival keratinocytes. (A–C) Relative mRNA expressions of interleukin (IL)–8, matrix metalloproteinase (MMP)–1, and MMP-3. (D–F) IL-8, MMP-1, and MMP-3 protein levels in culture supernatants were measured with enzyme-linked immunosorbent assay. *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001.

Figure 5.

Dasatinib and quercetin (DQ) mitigates gingival senescence and age-related periodontal bone loss. Balb/c mice (15 to 16 mo old) were treated with vehicle (n = 9) and DQ (n = 8) for 3 consecutive days per week every 2 wk for 3 mo. SA-β-galactosidase (A, B), lipofuscin deposition (C, D), p16 (E–G), senescence-related secretome (H–L), and alveolar bone loss (M, N). *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001.