Antiplanktonic and Antibiofilm Activity of Rheum palmatum against Streptococcus oralis and Porphyromonas gingivalis

Correction: Kommerein et al. Antiplanktonic and Antibiofilm Activity of Rheum palmatum Against Streptococcus oralis and Porphyromonas gingivalis. Microorganisms 2022, 10, 965

In the original publication [...].

In Silico Docking of Medicinal Herbs Against P. gingivalis for Chronic Periodontitis Intervention

OBJECTIVE

This study aimed to explore the therapeutic potential of medicinal herbs for chronic periodontitis by examining the molecular interactions between specific herbal compounds and the heme-binding protein of Porphyromonas gingivalis, a key pathogen involved in the disease.

METHODS

The crystal structure of heme-binding protein was obtained from the Protein Data Bank. Herbal compounds were identified through an extensive literature review. Molecular docking simulations were performed to predict binding affinities, followed by Absorption, Distribution, Metabolism, and Excretion (ADME) parameter prediction. Drug-likeness was assessed based on Lipinski's Rule of Five, and pharmacophore modeling was conducted to identify key molecular interactions.

RESULTS

The molecular docking simulations revealed that chelidonine, rotenone, and myricetin exhibited significant binding affinities to the heme-binding protein, with docking scores of -6.5 kcal/mol, -6.4 kcal/mol, and -6.1 kcal/mol, respectively. These compounds formed stable interactions with key amino acid residues within the binding pocket. ADME analysis indicated that all 3 compounds had favourable pharmacokinetic properties, with no violations of Lipinski's rules and minimal predicted toxicity. Pharmacophore modeling further elucidated the interaction profiles, highlighting specific hydrogen bonds and hydrophobic interactions critical for binding efficacy.

CONCLUSIONS

Chelidonine, rotenone, and myricetin emerged as promising therapeutic candidates for chronic periodontitis due to their strong binding affinities, favorable ADME profiles, and lack of significant toxicity. The detailed pharmacophore modeling provided insights into the molecular mechanisms underpinning their inhibitory effects on the heme-binding protein of P. gingivalis. These findings suggest that these compounds have the potential for further development as effective treatments for chronic periodontitis. Future research should focus on in vitro and in vivo validation of these findings to confirm the efficacy and safety of these compounds in biological systems.

The phytochemistry and pharmacology of three Rheum species: A comprehensive review with future perspectives

BACKGROUND

Rheum palmatum, R. tanguticum, and R. officinale, integral species of the genus Rheum, are widely used across global temperate and subtropical regions. These species are incorporated in functional foods, medicines, and cosmetics, recognized for their substantial bioactive components.

PURPOSE

This review aims to synthesize developments from 2014 to 2023 concerning the botanical characteristics, ethnopharmacology, nutritional values, chemical compositions, pharmacological activities, mechanisms of action, and toxicity of these species.

METHODS

Data on the three Rheum species were gathered from a comprehensive review of peer-reviewed articles, patents, and clinical trials accessed through PubMed, Google Scholar, Web of Science, and CNKI.

RESULTS

The aerial parts are nutritionally rich, providing essential amino acids, fatty acids, and minerals, suitable for use as health foods or supplements. Studies have identified 143 chemical compounds, including anthraquinones, anthrones, flavonoids, and chromones, which contribute to their broad pharmacological properties such as laxative, anti-diarrheal, neuroprotective, hepatoprotective, cardiovascular, antidiabetic, antitumor, anti-inflammatory, antiviral, and antibacterial effects. Notably, the materials science approach has enhanced understanding of their medicinal capabilities through the evaluation of bioactive compounds in different therapeutic contexts.

CONCLUSION

As medicinal and economically significant herb species, Rheum species provide both edible aerial parts and medicinal underground components that offer substantial health benefits. These characteristics present new opportunities for developing nutritional ingredients and therapeutic products, bolstering the food and pharmaceutical industries.

An In Vitro Study of Local Oxygen Therapy as Adjunctive Antimicrobial Therapeutic Option for Patients with Periodontitis

Periodontitis is a common global disease caused by bacterial dysbiosis leading to tissue destruction, and it is strongly associated with anaerobic bacterial colonization. Therapeutic strategies such as oxygen therapy have been developed to positively influence the dysbiotic microbiota, and the use of oxygen-releasing substances may offer an added benefit of avoiding systemic effects commonly associated with antibiotics taken orally or hyperbaric oxygen therapy. Therefore, the oxygen release of calcium peroxide (CaO₂) was measured using a dissolved oxygen meter, and CaO₂ solutions were prepared by dissolving autoclaved CaO₂ in sterile filtered and deionized water. The effects of CaO₂ on planktonic bacterial growth and metabolic activity, as well as on biofilms of Streptococcus oralis and Porphyromonas gingivalis, were investigated through experiments conducted under anaerobic conditions. The objective of this study was to investigate the potential of CaO₂ as an antimicrobial agent for the treatment of periodontitis. Results showed that CaO₂ selectively inhibited the growth and viability of P. gingivalis (p < 0.001) but had little effect on S. oralis (p < 0.01), indicating that CaO₂ has the potential to selectively affect both planktonic bacteria and mono-species biofilms of P. gingivalis. The results of this study suggest that CaO₂ could be a promising antimicrobial agent with selective activity for the treatment of periodontitis.

Oxygen-Releasing Hyaluronic Acid-Based Dispersion with Controlled Oxygen Delivery for Enhanced Periodontal Tissue Engineering

Periodontitis is a chronic biofilm-associated inflammatory disease of the tooth-supporting tissues that causes tooth loss. It is strongly associated with anaerobic bacterial colonization and represents a substantial global health burden. Due to a local hypoxic environment, tissue regeneration is impaired. Oxygen therapy has shown promising results as a potential treatment of periodontitis, but so far, local oxygen delivery remains a key technical challenge. An oxygen (O₂)-releasing hyaluronic acid (HA)-based dispersion with a controlled oxygen delivery was developed. Cell viability of primary human fibroblasts, osteoblasts, and HUVECs was demonstrated, and biocompatibility was tested using a chorioallantoic membrane assay (CAM assay). Suppression of anaerobic growth of Porphyromonas gingivalis was shown using the broth microdilution assay. In vitro assays showed that the O₂-releasing HA was not cytotoxic towards human primary fibroblasts, osteoblasts, and HUVECs. In vivo, angiogenesis was enhanced in a CAM assay, although not to a statistically significant degree. Growth of P. gingivalis was inhibited by CaO₂ concentrations higher than 256 mg/L. Taken together, the results of this study demonstrate the biocompatibility and selective antimicrobial activity against P. gingivalis for the developed O₂-releasing HA-based dispersion and the potential of O₂-releasing biomaterials for periodontal tissue regeneration.

Extracts of Rheum palmatum and Aloe vera Show Beneficial Properties for the Synergistic Improvement of Oral Wound Healing

Various local and systemic factors compromise oral wound healing and may lead to wound dehiscence, inflammation, or ulcers. Currently, there is a lack of topical therapeutical options. Thus, this study aimed to investigate the effect of Aloe vera (AV) and Rheum palmatum root (RPR) on oral wound healing capacity in vitro. The effect of AV and RPR on human primary fibroblast viability and migration was studied by measuring metabolic activity and gap closure in a scratch assay. Furthermore, cell cycle distribution and cytoskeletal features were analyzed. Antimicrobial activity against the oral pathogen Porphyromonas gingivalis was evaluated by broth microdilution assay. AV and RPR increased fibroblast migration after single agent treatment. Synergistic effects of the plant extract combination were observed regarding cellular migration which were confirmed by calculation of the phenomenological combination index (pCI), whereas the cell cycle distribution was not influenced. Furthermore, the combination of AV and RPR showed synergistic antibacterial effects as determined by the fractional inhibitory concentration index. This study demonstrated that the combination of AV and RPR can promote the migration of human primary fibroblasts in vitro and exert antimicrobial efficacy against P. gingivalis, suggesting these compounds for the topical treatment of wound healing disorders.