Antimicrobial and anti-viral effects of selenium nanoparticles and selenoprotein based strategies: COVID-19 and beyond

Deficiency of selenium (Se) has been described in a significant number of COVID-19 patients having a higher incidence of mortality, which makes it a pertinent issue to be addressed clinically for effective management of the COVID-19 pandemic. Se nanoparticles (SeNPs) provide a unique option for managing the havoc caused by the COVID-19 pandemic. SeNPs possess promising anti-inflammatory and anti-fibrotic effects by virtue of their nuclear factor kappa-light-chain-stimulator of activated B cells (NFκB), mitogen-activated protein kinase (MAPKs), and transforming growth factor-beta (TGF-β) modulatory activity. In addition, SeNPs possess remarkable immunomodulatory effects, making them a suitable option for supplementation with a much lower risk of toxicity compared to their elemental counterpart. Further, SeNPs have been shown to curtail viral and microbial infections, thus, making it a novel means to halt viral growth. In addition, it can be administered in the form of aerosol spray, direct injection, or infused thin-film transdermal patches to reduce the spread of this highly contagious viral infection. Moreover, a considerable decrease in the expression of selenoprotein along with enhanced expression of IL-6 in COVID-19 suggests a potential association among selenoprotein expression and COVID-19. In this review, we highlight the unique antimicrobial and antiviral properties of SeNPs and the immunomodulatory potential of selenoproteins. We provide the rationale behind their potentially interesting properties and further exploration in the context of microbial and viral infections. Further, the importance of selenoproteins and their role in maintaining a successful immune response along with their association to Se status is summarized.

Treatment of Reticular Oral Lichen Planus with Photodynamic Therapy: A Case Series

OBJECTIVES

The aim of the study was to clinically evaluate the efficacy of photodynamic therapy in treatment of the reticular form of oral lichen planus (OLP).

MATERIALS AND METHODS

Twenty patients aged 40-76, with 40 confirmed OLP lesions in total, underwent photodynamic therapy (PDT) following the authors' own protocol, which used 5% 5-aminolevulinic acid as a photosensitizer applied two hours prior to illumination with a diode lamp emitting light at 630 nm and 300 mW. The therapy comprised of 10 weekly illumination sessions and was clinically evaluated between its completion and the end of a 12-month follow-up.

RESULTS

While the baseline mean size of all 40 lesions was 2.74 ± 3.03 cm², it was 2.97 ± 3.4 cm² for the 30 lesions on the buccal mucosa and 2.02 ± 1.32 cm² for the remaining 10 on the gingiva and tongue. On completion of the therapy, 37 sites improved, including 14 showing complete remission. From that point, the mean size reduction of 56.2% (1.2 ± 1.4 cm²) rose to 67.88% (0.88 ± 1.3 cm²) 12 months later.

CONCLUSIONS

The results suggest that ALA-mediated photodynamic therapy was effective for the reticular form of OLP and may become an optional or complementary treatment.

Experimental and clinical trial investigations of phyto-extracts, phyto-chemicals and phyto-formulations against oral lichen planus: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Bio-assay guided phytoextracts and derived phytoconstituents reported having multipotent biological activities and nearly 60-80% of the global population still using natural regimens as an alternative therapeutic source. This study focused on the ethnopharmacological and experimental evidence of natural remedies that are effective in treating oral lichen planus (OLP), a chronic T-cell mediated autoimmune disease that is associated with oral cancer transmission.

AIM OF THE REVIEW

A number of studies have shown that antioxidants and antiinflammatory phytoextracts and phyto-constituents are effective against OLP. In this systematic review, we summarize the details of experimentally assessed ancient Traditional Chinese Medicine (TCM), Indian Ayurveda or Ayurvedic Medicine, and Japanese Kampo Medicine (JKM) regimens (crude extracts, individual phytochemicals, and phyto-formulations) that reduce oral lesion, severity index and pain associated with OLP based on studies conducted in vivo, in vitro, and in randomized controlled trials (RCTs).

MATERIALS AND METHODS

Experimental, clinical and RCT investigation reports were gathered and presented according to PRISMA-2020 format. Briefly, the information was obtained from PubMed, ScienceDirect, Wiley journal library, Scopus, Google Scholar with ClinicalTrials.gov (a clinical trial registry database operated by the National Library of Medicine in the United States). Further, individual phytochemical structures were verified from PubChem and ChemSpider databases and visualized by ChemDraw 18.0 software.

RESULTS

We summarized 11 crude phytoextracts, 7 individual phytochemicals, 9 crude formulations, 8 specific TCM and JKM herbal cocktails, and 6 RCTs/patents corroborated by multiple in vitro, in vivo and enzyme assay methods. Briefly, plants and their family name, used plant parts, reported phytochemicals and their chemical structure, treatment doses, and duration of each experiment were presented more concisely and scientifically.

CONCLUSION

Documentation of evidence-based natural ethnomedicines or remedies could be useful for promoting them as potential, cost-effective and less toxic alternatives or as complementary to commonly prescribed steroids towards the control of OLP.

Chemopreventive Agents in Oral Premalignancy: A Medical Management Review

Aims and Objective:

The term chemoprevention denotes the use of specific natural or synthetic chemical agents to prevent carcinogenesis. Chemoprevention may help delay the process of carcinogen activation and prevent the conversion of preneoplastic cells. These agents play an active role in the secondary level of prevention and reduce malignancy-associated morbidity and mortality. A new term, “prophylactic antioxidant therapy,” was coined and proposed. This review has assessed all major chemopreventive agents used for oral premalignancy and malignant conditions, which will reduce the economic burden on the patients.

Materials and Methods:

A systematic literature search was performed using PubMed, Medline, Embase, Cochrane Library, and EBSCO search, with language restriction to English. The search incorporated published literature from 1990 to 2018 using the medical subject heading terms. Literature search was performed using the following keywords: Chemoprevention, Premalignancy, and Oral Malignancy.

Results:

Of 99 publications related to the search strategy, 45 full articles relevant to the chemopreventive agents in premalignacy and oral malignancy were acquired for further inspection. Of the 45 articles, 30 met the inclusion criteria. Data were collected, and a brief summary of the studies regarding different chemopreventive agents that were most commonly used in oral premalignancy and malignancies was written.

Conclusion:

This review suggests administration of major chemopreventive agents for superior prognosis in individuals with an elevated risk of premalignancy and malignancy.

A clinical evaluation of efficacy of photodynamic therapy in treatment of reticular oral lichen planus: A case series

Background The aim of the study was to clinically evaluate the efficacy of photodynamic therapy in treatment of reticular oral lichen planus (OLP). Methods Fifty patients aged 26-84, with 124 OLP lesions in total, underwent photodynamic therapy (PDT) mediated with topically applied 5% 5-aminolevulinic acid. ALA was activated by a custom-made diode lamp with a high-power LED emitting light at 630 nm and 300 mW delivered through an optical fiber probe. A light exposure dose was 150 J/cm2. The therapy comprised of 10 weekly illumination sessions. The lesions' response was macroscopically measured in millimeters with a periodontal probe and clinically evaluated at each session, then on completion of the series and throughout the 12-month follow-up. Results The baseline mean size of lesions was 3.99 cm2±3.73. The lesions on the buccal mucosa and lips (lining mucosa) were larger than those on the gingiva and tongue (masticatory mucosa) - 4.58 cm2±4.01 and 2.93 cm2±2.91 respectively. On completion of the therapy 109 sites improved, including 46 in complete remission. The mean reduction in size was 62.91% (p = 0.000000). 12-month after therapy mean reduction of the lesions was 78.7% (p = 0.000000), specifically 79.48% (p = 0.000000) within the lining mucosa and 76.11% on the masticatory mucosa. Conclusions The results proved that ALA-mediated photodynamic therapy with a 630 nm light was effective and as such it can be used as an optional treatment for symptomatic OLP.

Evaluation of Potential Risk Factors that contribute to Malignant Transformation of Oral Lichen Planus: A Literature Review

AIM

Many studies have suggested that a lesion originally diagnosed as oral lichen planus (OLP) has different possibilities of undergoing malignant transformation in time, although these findings remain a controversial issue; for example, some studies reported different values of potential malignancy of OLP.

INTRODUCTION

World Health Organization (WHO) classifies OLP as a "potentially malignant disorder" with unspecified malignant transformation risk, and suggests that OLP patients should be closely monitored. Numerous studies have attempted to confirm the malignant transformation potential of OLP.

REVIEW RESULTS

The Cochrane Controlled Trials Register, Medline and EMBASE databases, PubMed, Google Scholar, Ovid, Up To Date, BMJ Clinical Evidence, MD Consult, and Science Direct were searched for papers published between 1997 and 2015. The medical subject heading search terms were "lichen planus," "oral lichen planus," "erosive oral lichen planus," "dysplasia," "oral precancerous condition," "oral premalignant condition," oral cancer, oral squamous cell carcinoma (OSCC), and atrophic lichen planus. A total of 120 English language abstracts were reviewed, and 50 relevant articles identified. Because of the extensive literature on the association between OLP and SCC, we have divided the data into genetic and non-genetic factors for more accurate assessment.

CONCLUSION

In this evidence base, malignant transformation ranges from 0 to 37% with a mean of 4.59%. The highest rate of malignancy was noted in erythematosus and erosive lesions. In this way, follow-up of OLP patients could be carried out more efficiently and appropriately.

CLINICAL SIGNIFICANCE

Oral lichen planus is a premalignant lesion. All types of OLP in any site of oral mucosa must be monitored regularly.

Serum and Saliva MMP-3 in Patients with OLP and Oral SCC

BACKGROUND

Matrix metalloproteinase-3 (MMP-3) plays a key role in development of cancer. The purpose of this study was to assess MMP-3 in the serum and saliva of patients with oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Thirty patients with OLP (8 reticular and 22 erosive forms), and 20 patients with OSCC (6 in low stage and 14 in advanced stage), were enrolled in this study, conducted at the Cancer Department, Clinic of Oral Medicine, Tehran University of Medical Sciences. The serum and saliva MMP-3 was assayed by ELISA method. Statistical analysis of the Student's t-test, ANOVA and Pearson correlation coefficient was performed. The mean saliva and serum levels of MMP-3 were significantly higher in patients with OSCC compared with OLP.

RESULTS

The serum and saliva MMP-3 concentrations increased from reticular form of OLP to erosive form of OLP, and increased further to low stage of OSCC and advanced stage of OSCC. Serum MMP-3 correlated significantly with unstimulated (r = 0.310, p = 0.038) and stimulated (r = 0.365, p < 0.026) saliva MMP-3.

CONCLUSION

Serum and saliva MMP-3 levels appear associated with OLP and OSCC.

Evaluation of the Effects of Dental Implants on Oral Lesions

Objective

To determine whether dental implants impress oral lesions, and to evaluate the nature of their effect on the lesions.

Materials and methods

A comprehensive search was done via Google and PubMed for articles (including case reports and literature reviews) containing the keywords ‘oral squamous cell carcinoma’ (OSCC), ‘oral lichen planus’ (OLP), ‘lichenoid contact reaction’ (LCR), ‘osseointegrated implants’, and ‘dental implants’, in the last 10 years (2002-2012).

Results

The study included 24 articles involving patients with dental implants, and some oral lesions (e.g. oral lichen planus and oral squamous cell carcinoma) or with a history of lesions. In these publications, there is evidence suggesting the possibility of emergence, exacerbation, recurrence, or even malignant transformation of the oral lesions after implant placement in some cases.

Conclusion

Based on our review of the literature, implant treatment does not seem to be completely safe under any circumstances, but may have some complications in subjects with certain diseases (e.g. oral lesions, autoimmune diseases, malignancies, allergic reactions, etc.). Therefore prior to treatment, patients should be fully informed of the risks.

Clinical significance

Implant treatment is best done with caution in patients with cancer or mucocutaneous disorders.

How to cite this article

Agha-Hosseini F, Rohani B. Evaluation of the Effects of Dental Implants on Oral Lesions. J Contemp Dent Pract 2015;16(5):400-406.

Toxicological and pharmacological concerns on oxidative stress and related diseases

Although reactive oxygen species (ROS) such as superoxide, hydrogen peroxide and hydroxyl radical are generated as the natural byproduct of normal oxygen metabolism, they can create oxidative damage via interaction with bio-molecules. The role of oxidative stress as a remarkable upstream part is frequently reported in the signaling cascade of inflammation as well as chemo attractant production. Even though hydrogen peroxide can control cell signaling and stimulate cell proliferation at low levels, in higher concentrations it can initiate apoptosis and in very high levels may create necrosis. So far, the role of ROS in cellular damage and death is well documented with implicating in a broad range of degenerative alterations e.g. carcinogenesis, aging and other oxidative stress related diseases (OSRDs). Reversely, it is cleared that antioxidants are potentially able to suppress (at least in part) the immune system and to enhance the normal cellular protective responses to tissue damage. In this review, we aimed to provide insights on diverse OSRDs, which are correlated with the concept of oxidative stress as well as its cellular effects that can be inhibited by antioxidants. Resveratrol, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, statins, nebivolol and carvedilol, pentaerythritol tetranitrate, mitochondria-targeted antioxidants, and plant-derived drugs (alone or combined) are the potential medicines that can be used to control OSRD.