Diosgenin prevents periodontitis by inhibiting inflammation and promoting osteogenic differentiation.

Diosgenin, an essential dietary steroidal sapogenin, possess multiple pharmacological activities. This study aimed to assess the effects of diosgenin on periodontitis and elucidate the mechanisms. Lipopolysaccharide (LPS)-stimulated human periodontal ligament stem cells (hPDLCs) and a Porphyromonas gingivalis (P.g) plus ligation-induced animal model were used for in vitro and in vivo studies, respectively. Inflammatory responses, nuclear factor κ-B (NF-κB) signaling and osteogenesis-related markers were measured both in LPS-stimulated hPDLSCs and in gingival tissue of periodontitis rats. Treatment with diosgenin significantly inhibited the production of tumor necrosis factor α (TNF-α), interleukin (IL)-1ß, and interleukin (IL)-6 and the activation of NF-κB pathway in LPS-stimulated hPDLSCs. Further, treatment with diosgenin enhanced the expression of osteoblast-related genes and increased the osteogenic differentiation capacity. Further, activation NF-κB pathway largely abolished the protective effects of diosgenin. Consistent with the in vitro studies, in vivo studies showed that administering diosgenin to periodontitis rats significantly lowered the levels of the TNF-α, IL-1ß, and IL-6 and the inflammatory transcription factor NF-κB in gingival tissue. In addition, osteoblast-related genes were promoted. Diosgenin attenuates periodontitis by adjusting NF-κB signaling to inhibit inflammatory effects and promoting osteogenesis, suggesting diosgenin might be developed as a therapeutic strategy for treating periodontitis in the future.

SPRC Suppresses Experimental Periodontitis by Modulating Th17/Treg Imbalance.

Object: The aims of the study were to explore the protective effects of S-propargyl-cysteine (SPRC) on periodontitis and to determine the underlying mechanisms. Methods: A rat periodontitis model was constructed by injecting LPS and SPRC (0, 25, and 50 mg/kg/d) was administered intraperitoneally. H2S and CSE level were detected. The alveolar bone level was evaluated by micro-CT, HE staining and methylene blue staining analysis. Inflammation-related factors, Treg and Th17 cells were detected by immunohistochemistry, RT-PCR, immunofluorescence, Western blot and flow cytometry. Phosphorylation levels of ERK1/2 and CREB were analysed. Results: The administration of SPRC significantly increased the expression of CSE in the gingival tissue and the concentration of endogenous H2S in the peripheral blood. Simultaneously, SPRC significantly inhibited the resorption of alveolar bone based on the H&E staining, micro-CT and methylene blue staining analysis. Compared with the periodontitis group, the levels of IL-17A, IL-10 were downregulated and IL-6,TGF-ß1 were upregulated in the SPRC groups. In the SPRC group, the percentage of TH17 cells and the expression of ROR-γt were downregulated, while the percentage of Tregs and the expression of Foxp3 were upregulated accompanied with inhibition of phosphorylation ERK1/2 and CREB. Conclusion: SPRC can prevent the progression of periodontitis by regulating the Th17/Treg balance by inhibition of the ERK/CREB signalling pathway.

In vitro anti­bacterial activity of diosgenin on Porphyromonas gingivalis and Prevotella intermedia.

Diosgenin (Dios), a natural steroidal sapogenin, is a bioactive compound extracted from dietary fenugreek seeds. It has a wide range of applications, exhibiting anti­oxidant, anti­inflammatory and anti­cancer activities. However, whether the extracts have beneficial effects on periodontal pathogens has so far remained elusive. The aim of the present study was to investigate the anti­bacterial effects of Dios on Porphyromonas gingivalis (P. gingivalis) and Prevotella intermedia (P. intermedia) in vitro. The anti­microbial effect of Dios on P. gingivalis and P. intermedia was assessed by a direct contact test (DCT) and the Cell Counting Kit (CCK)­8 assay at 60, 90 and 120 min. In addition, counting of colony­forming units (CFU) and live/dead cell staining were used to evaluate the anti­bacterial effects. The results of the DCT and CCK­8 assays indicated that Dios had beneficial dose­dependent inhibitory effects on P. gingivalis and P. intermedia. The CFU counting results also indicated that Dios had dose­dependent anti­bacterial effects on P. gingivalis and P. intermedia. Of note, Dios had significant anti­bacterial effects on the biofilms of P. gingivalis and P. intermedia in vitro as visualized by the live/dead cell staining method. In conclusion, the present results demonstrated that Dios had a marked anti­bacterial activity against P. gingivalis and P. intermedia in vitro, both in suspension and on biofilms. The present study highlighted the potential applications of Dios as a novel natural agent to prevent and treat periodontitis through its anti­bacterial effects.