Apitherapy and Periodontal Disease: Insights into In Vitro, In Vivo, and Clinical Studies

Porphyromonas gingivalis interaction with Candida albicans allows for aerobic escape, virulence and adherence

In the oral cavity Candida albicans interacts with many oral bacteria, including Porphyromonas gingivalis, both physically and metabolically. The aim of this in vitro study was to characterize these interactions and study their effects on the survival of P. gingivalis. First, metabolic interactions were evaluated by counting the colony forming units (CFU) after co-culturing. The results indicated that the anaerobic bacterium P. gingivalis survives under aerobic conditions when co-cultured with C. albicans. This is due to the oxygen consumption by C. albicans as determined by a reduction in survival upon the addition of Antimycin A. By measuring the protease activity, it was found that the presence of C. albicans induced gingipain activity by P. gingivalis, which is an important virulence factor. Adherence of P. gingivalis to hyphae of C. albicans was observed with a dynamic flow system. Using various C. albicans mutants, it was shown that the mechanism of adhesion was mediated by the cell wall adhesins, members of the agglutinin-like sequence (Als) family: Als3 and Als1. Furthermore, the two microorganisms could be co-cultured into forming a biofilm in which P. gingivalis can survive under aerobic culturing conditions, which was imaged using scanning electron microscopy. This study has further elucidated mechanisms of interaction, virulence acquisition and survival of P. gingivalis when co-cultured with C. albicans. Such survival could be essential for the pathogenicity of P. gingivalis in the oxygen-rich niches of the oral cavity. This study has emphasized the importance of interaction between different microbes in promoting survival, virulence and attachment of pathogens, which could be essential in facilitating penetration into the environment of the host.

Antioxidant Activity and Mechanism of Action of Amwaprin: A Protein in Honeybee (Apis mellifera) Venom

Bee venom contains several bioactive components, including enzymatic and non-enzymatic proteins. There is increasing interest in the bioactive components of bee venom since they have exhibited various pharmacological effects. Recently, Apis mellifera waprin (Amwaprin) was identified as a novel protein in Apis mellifera (honeybee) venom and characterized as an antimicrobial agent. Herein, the novel biological function of Amwaprin as an antioxidant is described. In addition, the antioxidant effects of Amwaprin in mammalian cells were investigated. Amwaprin inhibited the growth of, oxidative stress-induced cytotoxicity, and inflammatory response in mammalian NIH-3T3 cells. Amwaprin decreased caspase-3 activity during oxidative stress and exhibited protective activity against oxidative stress-induced cell apoptosis in NIH-3T3 and insect Sf9 cells. The mechanism underlying the cell protective effect of Amwaprin against oxidative stress is due to its direct binding to the cell membrane. Furthermore, Amwaprin demonstrated radical-scavenging activity and protected against oxidative DNA damage. These results suggest that the antioxidant capacity of Amwaprin is attributed to the synergistic effects of its radical-scavenging action and cell shielding, indicating its novel role as an antioxidant agent.

Bee Products and Colorectal Cancer—Active Components and Mechanism of Action

Colorectal cancer is one of the most common malignancies in the world. Lifestyle and eating patterns may have a significant impact on the prevention of this type of cancer. Bioactive food ingredients influence the gut microbiome and can have a protective effect. Bee products (honey, propolis, royal jelly, and bee venom) or pharmacologically active fractions obtained from them are widely used in many fields of medicine, pharmacy, and cosmetics. Some evidence suggests that bee products may have anti-cancer potential. The main bioactive components with anti-colon cancer potential from propolis and bee honey are polyphenols such as pinocembrin, galangin, luteolin, CAPE, Artepilin C, chrysin, caffeic, and p-coumaric acids. This review is focused on the new data on epidemiology, risk factors for colon cancer, and current reports on the potential role of bee products in the chemoprevention of this type of cancer.

Promising Antimicrobial Action of Sustained Released Curcumin-Loaded Silica Nanoparticles against Clinically Isolated Porphyromonas gingivalis

BACKGROUND

Porphyromonas gingivalis (P. gingivalis) has always been one of the leading causes of periodontal disease, and antibiotics are commonly used to control it. Numerous side effects of synthetic drugs, as well as the spread of drug resistance, have led to a tendency toward using natural antimicrobials, such as curcumin. The present study aimed to prepare and physicochemically characterize curcumin-loaded silica nanoparticles and to detect their antimicrobial effects on P. gingivalis.

METHODS

Curcumin-loaded silica nanoparticles were prepared using the chemical precipitation method and then were characterized using conventional methods (properties such as the particle size, drug loading percentage, and release pattern). P. gingivalis was isolated from one patient with chronic periodontal diseases. The patient's gingival crevice fluid was sampled using sterile filter paper and was transferred to the microbiology laboratory in less than 30 min. The disk diffusion method was used to determine the sensitivity of clinically isolated P. gingivalis to curcumin-loaded silica nanoparticles. SPSS software, version 20, was used to compare the data between groups with a p value of <0.05 as the level of significance. Then, one-way ANOVA testing was utilized to compare the groups.

RESULTS

The curcumin-loaded silica nanoparticles showed a nanometric size and a drug loading percentage of 68% for curcumin. The nanoparticles had a mesoporous structure and rod-shaped morphology. They showed a relatively rapid release pattern in the first 5 days. The release of the drug from the nanoparticles continued slowly until the 45th day. The results of in vitro antimicrobial tests showed that P. gingivalis was sensitive to the curcumin-loaded silica nanoparticles at concentrations of 50, 25, 12.5, and 6.25 µg/mL. One-way ANOVA showed that there was a significant difference between the mean growth inhibition zone, and the concentration of 50 µg/mL showed the highest inhibition zone (p ≤ 0.05).

CONCLUSION

Based on the obtained results, it can be concluded that the local nanocurcumin application for periodontal disease and implant-related infections can be considered a promising method for the near future in dentistry.

Physicochemical Profile, Antioxidant and Antimicrobial Activities of Honeys Produced in Minas Gerais (Brazil)

Honeys can be classified as polyfloral or monofloral and have been extensively studied due to an increased interest in their consumption. There is concern with the correct identification of their flowering, the use of analyses that guarantee their physicochemical quality and the quantification of some compounds such as phenolics, to determine their antioxidant and antimicrobial action. This study aims at botanical identification, physicochemical analyses, and the determination of total polyphenols, chromatographic profile and antiradical and antimicrobial activity of honey from different regions of Minas Gerais. Seven different samples were analyzed for the presence of pollen, and color determination. The physicochemical analyses performed were total acidity, moisture, HMF, reducing sugar, and apparent sucrose. The compound profile was determined by UHPLC/MS, the determination of total phenolics and antiradical activity (DPPH method) were performed by spectrophotometry, and minimum inhibitory and bacterial concentrations were determined for cariogenic bacteria. All honey samples met the quality standards required by international legislation, twenty compounds were detected as the main ones, the polyfloral honey was the only honey that inhibited all of the bacteria tested. Sample M6 (Coffee) was the one with the highest amount of total polyphenols, while the lowest was M4 (Cipó-uva). Regarding the antioxidant activity, M5 (Velame) had the best result and M4 (Cipó-uva) was the one that least inhibited oxidation. Of the polyfloral honeys, there was not as high a concentration of phenolic compounds as in the others. Coffee, Aroeira, Velame and Polyfloral have the best anti-radical actions. Betônica, Aroeira, Cipó-uva and Pequi inhibited only some bacteria. The best bacterial inhibition results are from Polyfloral.

Design, Characterization, and Anticancer and Antimicrobial Activities of Mucoadhesive Oral Patches Loaded with Usnea barbata (L.) F. H. Wigg Ethanol Extract F-UBE-HPMC

The oral cavity’s common pathologies are tooth decay, periodontal disease, and oral cancer; oral squamous cell carcinoma (OSCC) is the most frequent oral malignancy, with a high mortality rate. Our study aims to formulate, develop, characterize, and pharmacologically investigate the oral mucoadhesive patches (F-UBE-HPMC) loaded with Usnea barbata (L.) F.H. Wigg dry ethanol extract (UBE), using HPMC K100 as a film-forming polymer. Each patch contains 312 µg UBE, with a total phenolic content (TPC) of 178.849 µg and 33.924 µg usnic acid. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed for their morphological characterization, followed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Pharmacotechnical evaluation involved the measurement of the specific parameters for mucoadhesive oral patches as follows: weight uniformity, thickness, folding endurance, tensile strength, elongation, moisture content, pH, disintegration time, swelling rate, and ex vivo mucoadhesion time. Thus, each F-UBE-HPMC has 104 ± 4.31 mg, a pH = 7.05 ± 0.04, a disintegration time of 130 ± 4.14 s, a swelling ratio of 272 ± 6.31% after 6 h, and a mucoadhesion time of 102 ± 3.22 min. Then, F-UBE-HPMCs pharmacological effects were investigated using brine shrimp lethality assay (BSL assay) as a cytotoxicity prescreening test, followed by complex flow cytometry analyses on blood cell cultures and oral epithelial squamous cell carcinoma CLS-354 cell line. The results revealed significant anticancer effects by considerably increasing oxidative stress and blocking DNA synthesis in CLS-354 cancer cells. The antimicrobial potential against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27353, Candida albicans ATCC 10231, and Candida parapsilosis ATCC 22019 was assessed by a Resazurin-based 96-well plate microdilution method. The patches moderately inhibited both bacteria strains growing and displayed a significant antifungal effect, higher on C. albicans than on C. parapsilosis. All these properties lead to considering F-UBE-HPMC suitable for oral disease prevention and therapy.

Antibacterial and Antibiofilm Effect of Honey in the Prevention of Dental Caries: A Recent Perspective

The successful application of honey in wound care management has been achieved due to honey’s potent antibacterial effects, characterised by its multifactorial action. Impressive clinical efficacy has ignited its further use in diverse clinical disciplines, including stomatology. Indeed, there is increasing usage of honey in dental medicine as a preventive or therapeutic remedy for some periodontal diseases mainly associated with bacteria, such as dental caries, gingivitis and mucositides. Dental caries is undoubtedly a major oral health problem worldwide, with an increasing tendency of incidence. The purpose of this perspective review is to describe the recent progress in the laboratory and clinical use of honey in the prevention of dental caries, with emphasis on the antibacterial and antibiofilm effects of honey. The role of honey in the cariogenic process is also discussed. In addition, the quality of honey and the urgent in vitro evaluation of its antibacterial/antibiofilm properties before clinical use are highlighted. Findings based on data extracted from laboratory studies demonstrate the pronounced antibacterial effect of different honeys against a number of periodontal pathogens, including Streptococcus mutans. Although the promising antibiofilm effects of honey have been reported mainly against S. mutans, these results are limited to very few studies. From a clinical point of view, honey significantly reduces dental plaque; however, it is not superior to the conventional agent. Despite the positive in vitro results, the clinical effectiveness of honey in the prevention of dental caries remains inconclusive since further robust clinical studies are needed.