Kouqiangjie formula alleviates diabetic periodontitis by regulating alveolar bone homeostasis via miR-29a-3p-mediated Dkk-1/Wnt/β-catenin signaling pathway

Abstract

Ethnopharmacological relevance

Diabetic periodontitis (DP) is a commonly co-occurring complication in diabetes patients characterized by advanced gum disease and bone resorption. Conventional treatment modalities often fail to adequately address the underlying biological disruptions caused by diabetes. The use of traditional medicinal formulas Kouqiangjie Formula (KQJF) potentially offers novel therapeutic approaches for DP, but its detailed regulatory mechanisms remain unclear.

Aim of the study

This study aims to investigate the impacts of KQJF on osteoblastic activity and inflammatory responses in a rat model and in vitro pre-osteoblast cultures under conditions mimicking DP, focusing on the involvement of the miR-29a-3p-Dkk-1/Wnt/β-catenin signaling pathway.

Materials and methods

Using network pharmacological analysis, micro-CT, histological staining, and an array of molecular biology methodologies including Western blotting, RT-qPCR, and immunofluorescence, we investigated the systemic and cellular responses to KQJF treatment. Both in vivo (rat model) and in vitro (MC3T3-E1 pre-osteoblasts) models subjected to high glucose and lipopolysaccharide (HG + LPS) stress were used to simulate DP conditions.

Results

Network pharmacological analyses, incorporating protein-protein interactions and pathway enrichment, disclosed that KQJF interacts with pathways crucial for inflammation and bone metabolism. Experimentally, KQJF significantly preserved alveolar bone architecture, reduced osteoclast activity, and dampened inflammatory cytokine production in DP rats. In pre-osteoblasts, KQJF enhanced cell viability, promoted cell cycle progression, and decreased apoptosis. At the molecular level, KQJF treatment upregulated miR-29a-3p and downregulated Dkk-1, thereby activating the Wnt/β-catenin pathway. The interventional studies with miR-29a-3p antagonists and Dkk-1 knockdown further confirmed the regulatory role of the miR-29a-3p/Dkk-1 axis in mediating the effects of KQJF.

Conclusion

KQJF mitigates the deleterious effects of DP by enhancing osteoblastic activity and reducing inflammatory responses, predominantly through the modulation of the miR-29a-3p-Dkk-1/Wnt/β-catenin signaling pathway. These discoveries underscore the therapeutic promise of KQJF in managing bone and inflammatory complications of DP, offering insights into its mechanism, and supporting its use in clinical settings.