RESUMEN
Objective:To explore the effect of silent information regulator 1 (SIRT1) activator SRT1720 on inflammatory response in chronic periodontal disease mice and whether its mechanism is related to the toll like receptor 4 (TLR4)/nuclear factor κB (NF-κB) signaling pathway.Methods:Forty 8-week-old male C57BL/6 mice were selected and divided into a blank control group ( n=8) and an experimental group ( n=32). The experimental group mice were ligated with periodontal pockets and fed with high sugar drinking water. The experimental group was randomly divided into a model group ( n=8) and an SRT1720 group ( n=24). The blank control group and the model group were given physiological saline orally every day. The SRT1720 group was further divided into a low dose group [20 mg/(kg·d), n=8], a medium dose group [50 mg/(kg·d), n=8], and a high dose group [100 mg/(kg·d), n=8] based on the different doses of SRT1720. Four weeks later, the expression levels of interleukin-6 (IL-6), interleukin-1β (IL-1β) and monocyte chemoattractant protein-1 (MCP-1) in gingival crevicular fluid of mice in each group were detected by enzyme linked immunosorbent assay (ELISA); The real-time quantitative polymerase chain reaction (RT-qPCR) method was used to detect the mRNA expression levels of IL-6, IL-1β, MCP-1, SIRT1, TLR4, NF-kB p65 in the gingival tissue of mice in each group; Western blot was used to determine the expression levels of SIRT1, TLR4, and NF-κB p65 proteins in mouse gingival tissue. Results:Compared with the blank control group, the expression levels of IL-6, IL-1β, and MCP-1 inflammatory factors in the gingival crevicular fluid of experimental group mice increased, while the expression levels of IL-6, IL-1β, MCP-1, TLR4, NF-κB p65 mRNA in gingival tissue increased. The expression levels of TLR4, NF-κB p65 protein in gingival tissue increased, while the expression levels of SIRT1 mRNA and protein in gingival tissue decreased, with statistical significance (all P<0.05). Compared with the model group, the expression levels of IL-6, IL-1β, and MCP-1 inflammatory factors in the gingival crevicular fluid, IL-6, IL-1β, MCP-1, TLR4, NF-κB p65 mRNA expression levels in gingival tissue, and TLR4, NF-κB p65 protein expression levels in the gingival tissue of SRT1720 group mice showed a dose-dependent decrease. The expression levels of SIRT1 mRNA and protein in gingival tissue showed a dose-dependent increase, and the differences were statistically significant (all P<0.05). Conclusions:SIRT1 activator SRT1720 can improve the inflammatory response of chronic periodontal disease mice, which may be related to the inhibition of TLR4/NF-kB signaling pathway.
RESUMEN
Objective:To investigate the effects of bromodomain and extraterminal domain (BET) inhibitor JQ1 combined with siPD-L1 on the proliferation and apoptosis of oral squamous cell carcinoma (OSCC) Scc-25 cells and its mechanism.Methods:Scc-25 cells were cultured in vitro and treated with different concentrations of JQ1 (0, 0.2, 1, 5 μmol/L). Cell proliferation was detected by cell count kit-8 (CCK-8) assay; the expression levels of programmed cell death ligand 1(PD-L1) and forkhead box M1(FoxM1) protein were detected by Western blot. Appropriate concentration of JQ1 was selected for subsequent experiments. Scc-25 cells were divided into four groups: control group (without any treatment), siPD-L1 group (transfected with siPD-L1), JQ1 group (added JQ1 after transfected with non-specific siRNA), and combined treatment group (added JQ1 after transfected with siPD-L1). CCK-8 assay was used to detect the proliferation ability of Scc-25 cells in each group. Western blot was used to detect the expression levels of cleaved caspase-3, PD-L1 and FoxM1, and flow cytometry was used to detect the apoptosis rate of cells in each group. Results:With the increase of JQ1 concentration, the proliferation ability of SCC-25 cells and the expression levels of PD-L1 and FoxM1 decreased gradually (all P<0.01). JQ1 concentration of 1 μmol/L had obvious inhibitory effect on cell proliferation and the expression levels of PD-L1 and FoxM1, so JQ1 concentration of 1 μmol/L was selected for subsequent experiments. The proliferation ability of Scc-25 cells, the expression of PD-L1 and FoxM1 proteins in JQ1 group, siPD-L1 group and combination treatment group were significantly lower than those in the control group (all P<0.01), and the expression of cleaved caspase-3 protein and the rate of apoptosis were significantly higher than those in the control group (all P<0.01); Moreover, the effect of the combination treatment group was more significant than that of siPD-L1 group, JQ1 group (all P<0.01). Conclusions:The combination of JQ1 and siPD-L1 could effectively inhibit the proliferation and promotes the apoptosis of OSCC Scc-25 cells, and its mechanism may be related to the suppression of PD-L1 and FoxM1 signaling pathways.