Application of Ginsenoside Rd in Periodontitis With Inhibitory Effects on Pathogenicity, Inflammation, and Bone Resorption

3-methyl-1H-indol-1-yl dimethylcarbamodithioate attenuates periodontitis through targeting MAPK signaling pathway-regulated mitochondrial function

Periodontitis, the second most common oral disease, is primarily initiated by inflammatory responses and osteoclast differentiation, in which the MAPK signaling pathway and mitochondrial function play important roles. 3-methyl-1H-indol-1-yl dimethylcarbamodithioate (3o), a hybrid of indole and dithiocarbamate, was first synthesized by our group. It has shown anti-inflammatory activity against lipopolysaccharide-induced acute lung injury. However, it is not known if 3o can exert effects in periodontitis. In vitro study: LPS-induced macrophage inflammation initiation and a receptor activator of nuclear factor κB ligand-stimulated osteoclast differentiation model were established. Cell viability, inflammatory cytokines, osteoclast differentiation, the MAPK signaling pathway, and mitochondrial function before and after treatment with 3o were investigated. In vivo study: Alveolar bone resorption, inflammatory cytokine expression, osteoclast differentiation, and the underlying mechanisms were assessed in mice with periodontitis. Inflammatory cytokine expression and osteoclast differentiation appeared downregulated after 3o treatment. 3o inhibited the MAPK signaling pathway and restored mitochondrial function, including mitochondrial reactive oxygen species, mitochondrial membrane potential, and ATP production. Meanwhile, 3o reduced inflammation activation and bone resorption in mice with periodontitis, reflected by the decreased expression of inflammatory cytokines and osteoclasts, implying that 3o inhibited the MAPK signaling pathway and the mitochondrial oxidative DNA damage marker 8-OHdG. These results highlight the protective role of 3o in periodontitis in mice and reveal an important strategy for preventing periodontitis.

IRF4 Suppresses Osteogenic Differentiation of Periodontal Ligament Stem Cells by Activating IL-18 Signaling Pathway in Periodontitis

The present study aims to investigate the role of interferon regulatory factor 4 (IRF4) in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) and analyze the underlying signaling of these processes. In this study, IRF4 is upregulated in periodontitis periodontal ligament tissues, as compared to healthy periodontal ligament tissues. IRF4 knockdown increases cell proliferation, decreases levels of tumor necrosis factor-alpha, interleukin-6, and interleukin-8, enhances osteogenic activity, and increases the expression of RUNX family transcription factor 2, Collagen I, and Osteocalcin in PDLSCs. The opposite results are observed in IRF4 overexpressed PDLSCs. Additionally, GSEA shows that IRF4 activates the interleukin-18 (IL-18) signaling pathway. The expressions of IL-18, B-cell translocation gene 2, interleukin-1beta, and caspase-3 are decreased by IRF4 knockdown, while increased by IRF4 overexpression. IL-18 overexpression eliminates the promoting effect of IRF4 knockdown on osteogenic differentiation of PDLSCs. In conclusion, IRF4 suppresses osteogenic differentiation of PDLSCs by activating the IL-18 signaling pathway.

Eupatilin suppresses osteoclastogenesis and periodontal bone loss by inhibiting the MAPKs/Siglec-15 pathway

Periodontitis is a widely prevalent oral disease around the world characterized by the disruption of the periodontal ligament and the subsequent development of periodontal pockets, as well as the loss of alveolar bone, and may eventually lead to tooth loss. This research aims to assess the suppressive impact of Eupatilin, a flavone obtained from Artemisia argyi, on osteoclastogenesis in vitro and periodontitis in vivo. We found that Eupatilin can efficiently obstruct the differentiation of Raw264.7 and bone marrow-derived macrophages (BMDMs) induced by RANKL, leading to the formation of mature osteoclasts. Consistently, bone slice resorption assay showed that Eupatilin significantly inhibited osteoclast-mediated bone resorption in a dose-dependent manner. Eupatilin also downregulated the expression of osteoclast-specific genes and proteins in Raw264.7 and BMDMs. RNA sequencing showed that Eupatilin notably downregulated the expression of Siglec-15. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses identified significantly enriched pathways in DEGs, including MAPK signaling pathway. And further mechanistic investigations confirmed that Eupatilin repressed MAPKs/NF-κBsignaling pathways. It was found that Siglec-15 overexpression reversed the inhibitory impact of Eupatilin on the differentiation of osteoclasts. Furthermore, activating MAPK signaling pathway reversed the downregulation of Siglec-15 and the inhibition of osteoclastogenesis by Eupatilin. To sum up, Eupatilin reduced the expression of Siglec-15 by suppressing MAPK signaling pathway, ultimately leading to the inhibition of osteoclastogenesis. Meanwhile, Eupatilin suppressed the alveolar bone resorption caused by experimentalperiodontitis in vivo. Eupatilin exhibits potential therapeutic effects in the treatment of periodontitis, rendering it a promising pharmaceutical agent.

Therapeutic Potential of Ginsenosides on Bone Metabolism: A Review of Osteoporosis, Periodontal Disease and Osteoarthritis

Ginsenosides, bioactive compounds from the genus Panax, have potential therapeutic effects on diverse ailments, including diabetes. Emerging evidence suggests their involvement in bone metabolism. The present review summarizes the current understanding of the effects of ginsenosides on osteoporosis, periodontal disease, and osteoarthritis. Their mechanisms of action include effects on osteoblasts, osteoclasts, periodontal ligament fibroblasts (PDLFs), and chondrocytes, which are pivotal in maintaining bone, periodontal tissue, and cartilage homeostasis. Ginsenosides may exert their beneficial effects by enhancing PDLF and osteoblast activity, suppressing osteoclast function, augmenting chondrocyte synthesis in the cartilage matrix, and mitigating connective tissue degradation. Moreover, they possess antioxidant, anti-inflammatory, antimicrobial, and anti-pyroptotic properties. Their efficacy in increasing bone density, ameliorating periodontitis, and alleviating osteoarthritis symptoms has been demonstrated in preclinical studies using animal models. In terms of their mechanism of action, ginsenosides modulate cellular differentiation, activity, and key signaling pathway molecules, such as mitogen-activated protein kinases (MAPKs), while also regulating various mediators. Furthermore, the symptomatic relief observed in animal models lends further credence to their therapeutic utility. However, to translate these preclinical findings into clinical practice, rigorous animal and clinical investigations are imperative to ascertain the safety, efficacy, and optimal dosing regimens in human subjects.

Ameliorative Effect of Ginsenoside Rg6 in Periodontal Tissue Inflammation and Recovering Damaged Alveolar Bone

Periodontal disease is a chronic disease with a high prevalence, and in order to secure natural materials to prevent oral diseases, new materials that protect periodontal tissue from inflammation are being sought. Genes were identified using real-time quantitative polymerase chain reaction (RT-qPCR), and proteins were confirmed using Western blot. Dichlorodihydrofluorescein diacetate (DCF-DA) analysis was used, and the antibacterial effects were confirmed through Minimum Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) analysis. To confirm this effect in vivo, Sprague-Dawley rats, in which periodontitis was induced using ligation or Lipopolysaccharide of Porphyromonas gingivalis (PG-LPS), were used. In vitro experiments using human periodontal ligament (HPDL) cells stimulated with PG-LPS showed that Ginsenoside Rg6 (G-Rg6) had anti-inflammatory, antibacterial, antioxidant, and osteoblast differentiation properties. In vivo, G-Rg6 was effective in Sprague-Dawley rats in which periodontitis was induced using ligation or PG-LPS. Therefore, Ginsenoside Rg6 shows potential effectiveness in alleviating periodontitis.

Sulforaphene Inhibits Periodontitis through Regulating Macrophage Polarization via Upregulating Dendritic Cell Immunoreceptor

Periodontitis is one of the most prevalent chronic inflammatory diseases that may eventually lead to the loss of teeth. Macrophage polarization plays an important role in the development of periodontitis, and several naturally occurring food compounds have recently been reported to regulate macrophage polarization. In this study, we aimed to investigate the therapeutic potential of sulforaphene (SFE) in macrophage polarization and its impact on periodontitis. Through in vitro and in vivo experiments, our study demonstrated that SFE effectively inhibits M1 polarization while promoting M2 polarization, ultimately leading to the suppression of periodontitis. Transcriptome sequencing showed that SFE significantly upregulated the expression of dendritic cell immunoreceptor (DCIR, also known as CLEC4A2). We further validated the crucial role of DCIR in macrophage polarization through knockdown and overexpression experiments and demonstrated that SFE regulates macrophage polarization by upregulating DCIR expression. In summary, the results of this study suggest that SFE can regulate macrophage polarization and inhibit periodontitis. Moreover, this research identified DCIR (dendritic cell immunoreceptor) as a potential novel target for regulating macrophage polarization. These findings provide new insights into the treatment of periodontitis and other immune-related diseases.

"Medicine food homology" plants promote periodontal health: antimicrobial, anti-inflammatory, and inhibition of bone resorption

"Medicine food homology" (MFH) is a term with a lengthy history. It refers to the fact that a lot of traditional natural products have both culinary and therapeutic benefits. The antibacterial, anti-inflammatory and anticancer effects of MFH plants and their secondary metabolites have been confirmed by numerous research. A bacterially generated inflammatory illness with a complicated pathophysiology, periodontitis causes the loss of the teeth's supporting tissues. Several MFH plants have recently been shown to have the ability to prevent and treat periodontitis, which is exhibited by blocking the disease's pathogens and the virulence factors that go along with them, lowering the host's inflammatory reactions and halting the loss of alveolar bone. To give a theoretical foundation for the creation of functional foods, oral care products and adjuvant therapies, this review has especially explored the potential medicinal benefit of MFH plants and their secondary metabolites in the prevention and treatment of periodontitis.

Facile engineering of resveratrol nanoparticles loaded with 20(S)-protopanaxadiol for the treatment of periodontitis by regulating the macrophage phenotype

Periodontitis is an inflammatory disease, mainly caused by the formation of a subgingival plaque biofilm. In recent years, growing attention has been paid to immunotherapy in the treatment of periodontitis, and the importance of communal intervention associated with macrophage polarization was emphasized. Herein, resveratrol (RES) and 20(S)-protopanaxadiol (PPD) were successfully self-assembled into RES@PPD nanoparticles (NPs) by the phenolic resin reaction. RES@PPD NPs have good stability and biocompatibility. The combined application of PPD and RES enhances the anti-inflammatory and antioxidant properties of nanocomposites, remarkably reduces the level of reactive oxygen species, and finally realizes the coordinated regulation of host immunity in periodontitis. The detailed mechanism is as follows: RES@PPD NPs inhibit M1 polarization of macrophages, promote M2 polarization by scavenging ROS, and then inhibit the NF-κB signalling pathway to regulate host immunity. In the animal model of periodontitis, RES@PPD NPs can remarkably decrease the level of pro-inflammatory cytokines, up-regulate the anti-inflammatory cytokines, and exhibit a profound therapeutic effect on local inflammation. Therefore, RES@PPD NPs are effective in antioxidation and anti-inflammation, thus providing a promising candidate drug for the treatment of periodontitis.

Novel Herbal Therapeutic YH23537 Improves Clinical Parameters in Ligature-Induced Periodontal Disease Model in Beagle Dogs

Currently, available medicine does not satisfy the clinical unmet needs of periodontal disease. Therefore, novel drugs with improved efficacy profiles are needed. We previously demonstrated that YH14642, water extracts of Notoginseng Radix and Rehmanniae Radix Preparata, improved probing depths in double-blind phase II clinical trial. However, it still has hurdles for commercialization due to the low efficiency of active compound extraction. To resolve this issue, we developed YH23537 through process optimization to extract active compounds efficiently while still achieving the chemical profile of YH14642. In this study, we investigated the therapeutic effects of YH23537 compared with YH14642 using a canine model of ligature-induced periodontitis. Human gingival fibroblast (hGF) cells were treated with various concentrations of YH23537 or YH14642 with lipopolysaccharide (LPS) for 24 hr. IL-6 and IL-8 levels in the conditioned media were determined using Luminex. Sixteen 3-year-old male beagle dogs had their teeth scaled and polished using a piezo-type ultrasonic scaler under general anesthesia and brushed once daily for the following 2 weeks. Two weeks after the scaling procedure, the left upper second premolar (PM2), third premolar (PM3), and fourth premolar (PM4) as well as the left lower PM3, PM4, and first molar (M1) were ligated with silk-wire twisted ligatures. The dogs were fed with soft moistened food to induce periodontitis for 8 weeks, and the ligatures were then removed. YH23537 and YH14642 were administered for 4 weeks, and clinical periodontal parameters such as plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BoP) were determined before and 1, 2, 3, and 4 weeks after treatment. YH23537 inhibited IL-6 and IL-8 secretion in a dose-dependent manner in hGF cells stimulated with LPS. The IC₅₀ values for YH23537 were 43 and 54 μg/ml for IL-6 and IL-8, respectively, while the values for YH14642 were 104 and 117 μg/ml, respectively. In the animal study, clinical parameters including GI, PD, CAL, and BoP were significantly increased after 8 weeks of ligature-induced periodontitis. The YH23537 300 and YH23537 900 mg groups had significant improvements in CAL from 1 to 4 weeks after treatment in comparison to the placebo group. GR values in the YH23537 900 mg group were decreased throughout the treatment period. GI values were also reduced significantly after 4-week treatment with 300 and 900 mg of YH23537. YH23537 at 300 mg doses showed comparable efficacy for CAL and GR with 1,000 mg of YH14642. YH23537 showed therapeutic efficacy against periodontitis in dogs, mediated by anti-inflammatory effects. These findings indicate that YH23537 has the potential for further development as a new drug for patients suffering from periodontal disease.

Biotransformation, Pharmacokinetics, and Pharmacological Activities of Ginsenoside Rd Against Multiple Diseases

Panax ginseng C.A. Mey. has a history of more than 4000 years and is widely used in Asian countries. Modern pharmacological studies have proved that ginsenosides and their compounds have a variety of significant biological activities on specific diseases, including neurodegenerative diseases, certain types of cancer, gastrointestinal disease, and metabolic diseases, in which most of the interest has focused on ginsenoside Rd. The evidentiary basis showed that ginsenoside Rd ameliorates ischemic stroke, nerve injury, cancer, and other diseases involved in apoptosis, inflammation, oxidative stress, mitochondrial damage, and autophagy. In this review, we summarized available reports on the molecular biological mechanisms of ginsenoside Rd in neurological diseases, cancer, metabolic diseases, and other diseases. We also discussed the main biotransformation pathways of ginsenoside Rd obtained by fermentation.