A 30-s exposure to ethanol 20% is cytotoxic to human keratinocytes: possible mechanistic link between alcohol-containing mouthwashes and oral cancer

Does Mouthwash Use Affect Oral Cancer Risk? A Comprehensive Systematic Review and Meta-Analysis

Studies indicate a strong correlation between the length and degree of alcohol and tobacco use and the risk of oral cancer (OC). However, there has been debate concerning the usage of mouthwashes and associated higher risk of OC for many years. The purpose of this study was to gain insight into how using mouthwash influenced the risk of OC. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol was used when searching the PubMed/MEDLINE, Scopus, and Web of Science databases. Observational studies that addressed the relationship between mouthwash use and OC and involved adult or older adult populations were included. The Newcastle-Ottawa Scale was employed to check the methodological quality, and random effects meta-analysis, along with other subgroup analyses and meta-regression, were utilized to synthesize quantitative data. Out of 5,132 papers identified, 15 case-control studies comprising 6,515 cases and 17,037 controls were included in the review. Seventeen effect measures from these 15 studies were included in the meta-analysis. For individuals who used mouthwash three or more times a day, the pooled OR for OC was 1.00 (95% CI: 0.79-1.26; n = 17 studies). Among those who had used mouthwash for more than 40 years, the OR was 1.30 (95% CI: 1.58-4.82; p = 0.05; n = 2 studies). Some studies suggest that frequent mouthwash use may increase the risk of OC. Given the biological plausibility of this link, we exercise caution in interpreting these findings. It is important to note the limited research on the frequency and duration of mouthwash use. Thus, for the strengthening of the evidence for a possible dose-response effect of mouthwashes on OC risk, we suggest that future research should be focused on the frequency, duration, and substance of mouthwashes in depth.

Efficacy of Ceragenins in Controlling the Growth of Oral Microorganisms: Implications for Oral Hygiene Management

Ensuring proper dental hygiene is of paramount importance for individuals' general well-being, particularly for patients receiving medical care. There is a prevailing utilization of conventional oral hygiene items, including toothbrushes and mouthwashes, which have gained widespread acceptance; nevertheless, their limitations encourage investigating novel options in this domain. Our study indicates that ceragenins (CSAs) being lipid analogs of host defense peptides, well-recognized for their wide-ranging antimicrobial properties, may be a potentially efficacious means to augment oral hygiene in hospitalized individuals. We demonstrate that ceragenins CSA-13, CSA-44, and CSA-131 as well as undescribed to date CSA-255 display potent antimicrobial activities against isolates of fungi, aerobic, and anaerobic bacteria from Candida, Streptococcus, Enterococcus, and Bacteroides species, which are well-recognized representatives of microbes found in the oral cavity. These effects were further confirmed against mono- and dual-species fungal and bacterial biofilms. While the ceragenins showed similar or slightly diminished efficacy compared to commercially available mouthwashes, they demonstrated a highly favorable toxicity profile toward host cells, that may translate into better maintenance of host mucosal membrane stability. This suggests that incorporating ceragenins into oral hygiene products could be a valuable strategy for reducing the risk of both oral cavity-localized and secondary systemic infections and for improving the overall health outcomes of individuals receiving medical treatment.

The Effects of Antimicrobial Mouthwashes on Systemic Disease: What Is the Evidence?

The potential association between antimicrobial mouthwash use and systemic health has gained attention in recent years with reports highlighting how some common systemic conditions are influenced by the use of different types of mouthwashes. In this context, links between mouthwash use and cardiovascular disease, diabetes mellitus, oral cancer, Alzheimer's disease, and preeclampsia have been proposed, albeit with limited levels of evidence. Chlorhexidine mouthwash in particular has been the most widely studied agent while available data on other types of over-the-counter mouthwashes are generally scarce. Furthermore, there is currently no evidence-based recommendations on the appropriate use of mouthwashes during pregnancy. This article will present the current evidence on the association between mouthwash use and the aforementioned conditions with emphasis on the mechanisms that may underlie such an association.

Formulation of water-soluble Buddleja globosa Hope extracts and characterization of their antimicrobial properties against Pseudomonas aeruginosa

Buddleja globosa Hope (BG) extracts are traditionally used to treat skin and gastric ulcers due to their healing properties. Non-aqueous solvents such as ethanol and DMSO are usually used to extract naturally occurring compounds. However, the cytotoxicity of these solvents and the low water solubility of the extracted compounds can hinder their biomedical applications. To overcome the limited solubility of the BG extracts, we aimed to enhance the solubility by processing a standardized hydroalcoholic extract (BG-126) through spray drying (SD), with and without two solubility enhancers. Spray-dried BG (BG-SD) extracts and spray-dried BG extracts plus polyvinylpyrrolidone (BG-SD PVP) and Soluplus® (BG-SD SP) were developed starting from BG-126 (containing 53% ethanol). These four formulations were characterized by total phenolic content, water solubility at 25°C and 37°C, and antimicrobial properties against Pseudomonas aeruginosa. All the SD formulations presented a solubility that allowed them to reach maximum concentrations of 1,024 μg/ml catechin for BG-SD and 2,048 μg/ml catechin for BG-SD PVP and BG-SD SP for antimicrobial testing. BG-SD showed the highest antimicrobial potency with a minimum inhibitory concentration (MIC) of 512 μg/ml catechin, followed by BG-126 with a MIC of 1,024 μg/ml catechin and SP. BG-126 was also shown to inhibit biofilm formation, as well as the excipients PVP and SP. The spray-dried BG (BG-SD) extract represents a promising natural active component with enhanced antimicrobial properties against P. aeruginosa for further research and the development of novel phytopharmaceuticals.

Acute ethanol exposure stimulates microvesicle particle generation in keratinocytes

Ethanol has been demonstrated to exert profound effects upon cells and tissues via multiple mechanisms. One recently appreciated means by which cells can communicate with other cells is via the production and release of extracellular vesicles. Though smaller exosomes have been demonstrated to be released in response to ethanol exposure, the ability of ethanol to modulate the generation and release of larger microvesicle particles (MVP) is lesser studied. The present studies examined the ability of exogenous ethanol to generate MVP with a focus on skin cells. Acute ethanol exposure resulted in augmented MVP release in keratinocytes and in the skin and blood of mice. Unlike other stimuli such as ultraviolet B radiation or thermal burn injury, ethanol-mediated MVP release was independent of the Platelet-activating Factor receptor (PAFR). However, ethanol pretreatment was found to augment thermal burn injury-induced MVP in a PAFR-dependent manner. These studies provide a novel mechanism for ethanol-mediated effects, that could be relevant in the significant toxicity associated with thermal burn injury in the setting of alcohol intoxication.

Anti-Inflammatory and Protective Effects of Juncus effusus L. Water Extract on Oral Keratinocytes

Periodontitis is a chronic inflammatory disease caused by periodontopathogenic bacteria that form biofilms in periodontal pockets. The gingival epithelium acts as the first physical barrier in fighting attacks by periodontopathogenic pathogens, such as the primary etiological agent Porphyromonas gingivalis, and various exogenous chemicals, as well as regulates the local innate immune responses. Therefore, the development of novel oral care products to inhibit inflammatory reactions caused by bacterial infection and protect the gingival epithelium is necessary. Juncus effusus L. has generally been used as an indigenous medicine, such as a diuretic, an antipyretic, and an analgesic, in ancient practice. In this study, we examined the effects of a water extract from J. effusus L. on the inhibition of the inflammatory reaction elicited by bacterial infection and protection of the oral epithelium by chemical irritation. Pretreatment of oral epithelial cells with the water extract from J. effusus L. significantly reduced P. gingivalis or its lipopolysaccharide- (LPS-) mediated production of chemokines (interleukin-8 and C-C-chemokine ligand20) in a concentration-dependent manner with comparable to or greater effects than epigallocatechin gallate and protected oral epithelial cells from injury by chemical irritants, cetylpyridinium chloride, and benzethonium chloride. Moreover, the water extract from J. effusus L. in the presence of antimicrobial agents or antifibrinolytics already used as ingredients in mouthwash could significantly reduce the production of chemokines from P. gingivalis LPS-stimulated oral epithelial cells in a concentration-dependent manner. These findings suggest that the water extract from J. effusus L. is potentially useful for oral care to prevent oral infections, such as periodontal infections, and maintain oral epithelial function.

Biochemical Mechanisms Associating Alcohol Use Disorders with Cancers

Simple Summary

Of all yearly deaths attributable to alcohol consumption globally, approximately 12% are due to cancers, representing approximately 0.4 million deceased individuals. Ethanol metabolism disturbs cell biochemistry by targeting the structure and function of essential biomolecules (proteins, nucleic acids, and lipids) and by provoking alterations in cell programming that lead to cancer development and cancer malignancy. A better understanding of the metabolic and cell signaling realm affected by ethanol is paramount to designing effective treatments and preventive actions tailored to specific neoplasias.

Abstract

The World Health Organization identifies alcohol as a cause of several neoplasias of the oropharynx cavity, esophagus, gastrointestinal tract, larynx, liver, or female breast. We review ethanol’s nonoxidative and oxidative metabolism and one-carbon metabolism that encompasses both redox and transfer reactions that influence crucial cell proliferation machinery. Ethanol favors the uncontrolled production and action of free radicals, which interfere with the maintenance of essential cellular functions. We focus on the generation of protein, DNA, and lipid adducts that interfere with the cellular processes related to growth and differentiation. Ethanol’s effects on stem cells, which are responsible for building and repairing tissues, are reviewed. Cancer stem cells (CSCs) of different origins suffer disturbances related to the expression of cell surface markers, enzymes, and transcription factors after ethanol exposure with the consequent dysregulation of mechanisms related to cancer metastasis or resistance to treatments. Our analysis aims to underline and discuss potential targets that show more sensitivity to ethanol’s action and identify specific metabolic routes and metabolic realms that may be corrected to recover metabolic homeostasis after pharmacological intervention. Specifically, research should pay attention to re-establishing metabolic fluxes by fine-tuning the functioning of specific pathways related to one-carbon metabolism and antioxidant processes.

Identification of Gingivitis-Related Genes Across Human Tissues Based on the Summary Mendelian Randomization

Periodontal diseases are among the most frequent inflammatory diseases affecting children and adolescents, which affect the supporting structures of the teeth and lead to tooth loss and contribute to systemic inflammation. Gingivitis is the most common periodontal infection. Gingivitis, which is mainly caused by a substance produced by microbial plaque, systemic disorders, and genetic abnormalities in the host. Identifying gingivitis-related genes across human tissues is not only significant for understanding disease mechanisms but also disease development and clinical diagnosis. The Genome-wide association study (GWAS) a commonly used method to mine disease-related genetic variants. However, due to some factors such as linkage disequilibrium, it is difficult for GWAS to identify genes directly related to the disease. Hence, we constructed a data integration method that uses the Summary Mendelian randomization (SMR) to combine the GWAS with expression quantitative trait locus (eQTL) data to identify gingivitis-related genes. Five eQTL studies from different human tissues and one GWAS studies were referenced in this paper. This study identified several candidates SNPs and genes relate to gingivitis in tissue-specific or cross-tissue. Further, we also analyzed and explained the functions of these genes. The R program for the SMR method has been uploaded to GitHub(https://github.com/hxdde/SMR).

Charcoal-based mouthwashes: a literature review

The commercial marketplace has seen a rapid increase in the number of over-the-counter charcoal-containing mouthwashes. The purpose of this systemic review was to examine the clinical and laboratory evidence supporting therapeutic claims of efficacy and safety of use of charcoal-based mouthwashes. Secondly, the product labels and information of 36 commercially marketed charcoal mouthwashes were reviewed for active ingredients. Only 8% of charcoal mouthwashes contained an active ingredient, such as cetylpyridinium chloride or chlorhexidine. There is insufficient evidence to substantiate the therapeutic and cosmetic marketing claims of charcoal-based mouthwashes, including antimicrobial activity, anti-halitosis, tooth whitening, periodontal disease control, caries reduction and tooth remineralisation, among others. Moreover, there is no available information on charcoal particulate size or abrasivity of any of these products. Dental clinicians should advise their patients to exercise caution when using over-the-counter charcoal-containing mouthwashes because of the lack of evidence supporting therapeutic or cosmetic effectiveness as well as safety.

Meroterpenoids from the Brown Alga Cystoseira usneoides as Potential Anti-Inflammatory and Lung Anticancer Agents

The anti-inflammatory and anticancer properties of eight meroterpenoids isolated from the brown seaweed Cystoseira usneoides have been evaluated. The algal meroterpenoids (AMTs) 1-8 were tested for their inhibitory effects on the production of the pro-inflammatory cytokines tumor necrosis factor (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), and the expression of cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) in LPS-stimulated THP-1 human macrophages. The anticancer effects were assessed by cytotoxicity assays against human lung adenocarcinoma A549 cells and normal lung fibroblastic MRC-5 cells, together with flow cytometry analysis of the effects of these AMTs on different phases of the cell cycle. The AMTs 1-8 significantly reduced the production of TNF-α, IL-6, and IL-1β, and suppressed the COX-2 and iNOS expression, in LPS-stimulated cells (p < 0.05). The AMTs 1-8 displayed higher cytotoxic activities against A549 cancer cells than against MRC-5 normal lung cells. Cell cycle analyses indicated that most of the AMTs caused the arrest of A549 cells at the G2/M and S phases. The AMTs 2 and 5 stand out by combining significant anti-inflammatory and anticancer activities, while 3 and 4 showed interesting selective anticancer effects. These findings suggest that the AMTs produced by C. usneoides may have therapeutic potential in inflammatory diseases and lung cancer.

The Contribution of Photodynamic Inactivation vs. Corsodyl Mouthwash to the Control of Streptococcus mutans Biofilms

This work compared the inhibition effect of the commercially available mouthwash Corsodyl, containing 0.1% chlorhexidine digluconate, and photodynamic inactivation (PDI) employing methylene blue (MB) with irradiation from a red laser on 24-h biofilms formed by Streptococcus mutans strains on hydroxyapatite surfaces. The cytotoxicity of Corsodyl and MB was evaluated by Galleria mellonella surviving assay. The viability of biofilm cells after exposure to mouthwash and PDI was determined by counting colony-forming units. The inhibitory effect of antimicrobial agents was confirmed by confocal scanning laser microscopy. MB did not exhibit a cytotoxic effect on larval survival. Non-diluted Corsodyl slightly decreased the survival of larvae. Using our PDI parameters achieved better inhibition than with non-PDI, proving a significant effect on the eradication of S. mutans biofilms and therefore could be an appropriate supplement for the eradication of dental caries.

Anti-inflammatory potential of an essential oil-containing mouthwash in elderly subjects enrolled in supportive periodontal therapy: a 6-week randomised controlled clinical trial

OBJECTIVES

Essential oils and other plant extracts have evoked interest as sources of natural medicinal products. They have been proven to exert antibacterial, antifungal, antiviral and antioxidant properties, but the mechanism of action has not been fully elucidated.

AIM

This study aims to evaluate the potential of a sage-containing mouthwash to alleviate inflammatory signs of intra-oral mucosa and gingiva in comparison with a water/alcohol-based placebo.

MATERIAL AND METHODS

This study was conducted as a randomised, placebo-controlled, double-blind, parallel design clinical study. Forty-eight dentate subjects were randomly assigned to a test (sage-containing mouthwash) or a placebo group (water/alcohol-based solution). Subjects rinsed once daily for 30 s over a period of 6 weeks. Sulcus Bleeding Index (SBI), Plaque Index (PLI), tooth staining, xerostomia and degree of stomatitis were assessed at baseline and after 6 weeks.

RESULTS

Subjects' mean age was 77.5 ± 7.3 years. SBI was reduced from 1.3 ± 0.9 to 0.8 ± 0.7 (test, p = 0.0029) and 1.4 ± 0.9 to 1.1 ± 0.7 (placebo, p = 0.0105). Similarly, PLI was reduced from 1.2 ± 0.5 to 1.0 ± 0.3 (test, p = 0.0080) and 1.3 ± 0.4 to 1.1 ± 0.6 (placebo, p = 0.0087); no between-group differences were found (p > 0.05). Stomatitis, xerostomia and tooth staining revealed no change after 6 weeks.

CONCLUSION

The irrigation with a sage-containing mouthwash did not result in a superior beneficial effect on inflammatory parameters and plaque indices compared with the placebo. The expected contribution of the plant extracts to their potential impact on oral health may need further investigation.

CLINICAL RELEVANCE

The proposed mouthwash might be suitable for patients with inflammatory signs of the gingiva who prefer natural remedies.