Integrating network pharmacology and experimental evaluation to explore the complementary therapeutic effect and mechanism of melatonin in periodontitis.

Objective: To explore the potential targets for melatonin in the treatment of periodontitis through network pharmacologic analysis and experimental validation via in vivo animal models and in vitro cellular experiments. Materials and methods: In this study, we first screened melatonin targets from Pharm Mapper for putative targets, Drug Bank, and TCMSP databases for known targets. Then, disease database was searched and screened for differential expressed genes associated with periodontitis. The intersection of disease and melatonin-related genes yielded potential target genes of melatonin treatment for periodontitis. These target genes were further investigated by protein-protein interaction network and GO/KEGG enrichment analysis. In addition, the interactions between melatonin and key target genes were interrogated by molecular docking simulations. Then, we performed animal studies to validate the therapeutic effect of melatonin by injecting melatonin into the peritoneal cavity of ligation-induced periodontitis (LIP) mice. The effects of melatonin on the predicted target proteins were also analyzed using Western blot and immunofluorescence techniques. Finally, we constructed an in vitro cellular model and validated the direct effect of melatonin on the predicted targets by using qPCR. Results: We identified 8 potential target genes by network pharmacology analysis. Enrichment analysis suggests that melatonin may treat periodontitis by inhibiting the expression of three potential targets (MPO, MMP8, and MMP9). Molecular docking results showed that melatonin could effectively bind to MMP8 and MMP9. Subsequently, melatonin was further validated in a mouse LIP model to inhibit the expression of MPO, MMP8, and MMP9 in the periodontal tissue. Finally, we verified the direct effect of melatonin on the mRNA expression of MPO, MMP8, and MMP9 in an in vitro cellular model. Conclusions: Through a combination of network pharmacology and experimental validation, this study provides a more comprehensive understanding of the mechanism of melatonin to treat periodontitis. Our study suggests that MPO, MMP8, and MMP9 as key target genes of melatonin to treat periodontitis. These findings present a more comprehensive basis for further investigation into the mechanisms of pharmacological treatment of periodontitis by melatonin.

Computational analysis of curcumin-mediated alleviation of inflammation in periodontitis patients with experimental validation in mice.

AIM: Using network pharmacology and experimental validation to explore the therapeutic efficacy and mechanism of curcumin (Cur) in periodontitis treatment. MATERIALS AND METHODS: Network pharmacology was utilized to predict target gene interactions of Cur-Periodontitis. Molecular docking was used to investigate the binding affinity of Cur for the predicted targets. A mouse model with ligature-induced periodontitis (LIP) was used to verify the therapeutic effect of Cur. Microcomputed tomography (micro-CT) was used to evaluate alveolar bone resorption, while western blotting, haematoxylin-eosin staining and immunohistochemistry were used to analyse the change in immunopathology. SYTOX Green staining was used to assess the in vitro effect of Cur in a mouse bone marrow-isolated neutrophil model exposed to lipopolysaccharide. RESULTS: Network pharmacology identified 114 potential target genes. Enrichment analysis showed that Cur can modulate the production of neutrophil extracellular traps (NETs). Molecular docking experiments suggested that Cur effectively binds to neutrophil elastase (ELANE), peptidylarginine deiminase 4 (PAD4) and cathepsin G, three enzymes involved in NETs. In LIP mice, Cur alleviated alveolar bone resorption and reduced the expression of ELANE and PAD4 in a time-dependent but dose-independent manner. Cur can directly inhibit NET formation in the cell model. CONCLUSIONS: Our research suggested that Cur may alleviate experimental periodontitis by inhibiting NET formation.

Electroacupuncture regulates macrophage, neutrophil, and oral microbiota to alleviate alveolar bone loss and inflammation in experimental ligature-induced periodontitis.

AIM: Electroacupuncture (EA) regulates distant body physiology through somatic sensory autonomic reflexes, balances the microbiome, and can promote the release of immune cells into bloodstream, thereby inhibiting severe systemic inflammation. This makes it possible to use EA as an integrated treatment for periodontitis. MATERIALS AND METHODS: In this study, EA was applied to the ST36 acupoints in a ligature-induced periodontitis (LIP) mouse model. Then the effects of EA on periodontal myeloid cells, cytokines, and the microbiome were comprehensively analysed using flow cytometry, quantitative Polymerase Chain Reaction (PCR), and 16 S sequencing. RESULTS: Results demonstrated that EA could significantly relieve periodontal bone resorption. EA also suppressed the infiltration of macrophages and neutrophils, reduced gene expression of the pro-inflammatory cytokines IL-1ß, IL-6, IL-17 and TNF-α, and increased expression of the anti-inflammatory factors IL-4 and IL-10 in periodontal tissues. Moreover, composition of the periodontal microbiome was regulated by EA, finding that complex of microbiota, including supragingival Veillonella, subgingival Streptococcus, and subgingival Erysipelatoclostridium, were significantly reduced. Meanwhile, nitrate and nitrate-related activities of subgingival microbiota were reversed. Network analysis revealed close relationships among Veillonella, Streptococcus, and Bacteroides. CONCLUSIONS: Our study indicates that EA can effectively alleviate inflammation and bone resorption in LIP mice, potentially via the regulation of myeloid cells, cytokines, and periodontal microbiome.