Association of nitric oxide with oral lichen planus

Antioxidant therapy for patients with oral lichen planus: A systematic review and meta-analysis

Aims: This study aimed to systematically review the efficacy and safety of antioxidants for patients with Oral lichen planus (OLP). Methods: Databases, including PubMed, Web of Science, Cochrane Library, Embase, and Google Scholar, were searched up to 30 April 2022, for randomized controlled trials on the antioxidant therapy of OLP. The following endpoints were analyzed: pain score, clinical score, pain resolution rate, clinical resolution rate, and adverse effects. Results: A total of 19 studies met the inclusion criteria, and 17 studies with 704 patients were included in the meta-analysis. The findings showed that antioxidant therapy could significantly reduce the pain score [standardized mean difference -0.72 (-1.36, -0.07), P = 0.03, I2 = 87%, PI2 < 0.00001] and clinical score [SMD -2.06 (-3.06, -1.06), P < 0.0001, I2 = 94%, PI2 < 0.00001] of patients with OLP and improve the pain resolution rate [risk ratio (RR) 1.15 (1.01, 1.31), P = 0.04, I2 = 45%, PI2 = 0.09] and clinical resolution rate [RR 1.40 (1.10, 1.78), P = 0.006, I2 = 72%, PI2 = 0.002]. Conclusion: The study demonstrated that antioxidant therapy was beneficial for patients with OLP, and antioxidants might be used to treat OLP. Systematic Review Registration: https://clinicaltrials.gov/, identifier CRD4202233715.

Hallmarks of Cancer Expression in Oral Lichen Planus: A Scoping Review of Systematic Reviews and Meta-Analyses

Oral lichen planus (OLP) is a common chronic inflammatory disease of unknown etiology and likely autoimmune nature that is currently considered an oral potentially malignant disorder, implying that patients suffering from this process are at risk of developing oral cancer in their lifetime. The molecular alterations that develop in OLP and that make the affected oral epithelium predisposed to malignancy are unknown, although, as in other autoimmune diseases (ulcerative colitis, primary biliary cirrhosis, etc.), they may be linked to oncogenesis-promoting effects mediated by the inflammatory infiltrate. So far there is no in-depth knowledge on how these hallmarks of cancer are established in the cells of the oral epithelium affected by OLP. In this scoping review of systematic reviews and meta-analyses the state of evidence based knowledge in this field is presented, to point out gaps of evidence and to indicate future lines of research. MEDLINE, Embase, Cochrane Library and Dare were searched for secondary-level studies published before October 2022. The results identified 20 systematic reviews and meta-analyses critically appraising the hallmarks tumor-promoting inflammation (n = 17, 85%), sustaining proliferative signaling (n = 2, 10%), and evading growth suppressors (n = 1, 5%). No evidence was found for the other hallmarks of cancer in OLP. In conclusion, OLP malignization hypothetically derives from the aggressions of the inflammatory infiltrate and a particular type of epithelial response based on increased epithelial proliferation, evasion of growth-suppressive signals and lack of apoptosis. Future evidence-based research is required to support this hypothesis.

The efficacy of injectable platelet-rich fibrin in the treatment of symptomatic oral lichen planus

OBJECTIVES

The use of autologous platelet concentrates has shown growing evidence as a promising therapy. We conducted a split-mouth study to evaluate the effectiveness of injectable platelet-rich fibrin (PRF) compared to triamcinolone acetonide (TA) in the treatment of oral lichen planus (OLP).

MATERIALS AND METHODS

This split-mouth randomized trial included twelve patients with symptomatic, bilateral OLP lesions. The participants were randomly allocated to receive a 1-mL intralesional PRF injection on one side of the buccal mucosa and a 0.5-mL TA injection on the counterpart side. The application was performed once a week for 4 weeks. The outcomes were measured using a visual analog scale score, REU score, and lesion areas.

RESULTS

Both injectable TA and PRF were effective in the management of oral lichen planus. After four weeks of treatment, there was an average reduction in the VAS score (68.5% i-PRF, 91% TA) and an average reduction in the REU score (74% i-PRF, 91% TA). There were no statistically significant differences between the two treatment methods (P > 0.05).

CONCLUSIONS

Intralesional injection with TA showed more effectiveness than i-PRF in the management of OPL lesions. Although, i-PRF cannot be considered a first-line treatment option, it showed promising alternative therapy choice with no side effects.

Systematic Review and Meta-Analysis of Oxidative Stress and Antioxidant Markers in Oral Lichen Planus

Background

Oral lichen planus (OLP) is a relatively common chronic inflammatory disease of unknown etiology, which might be caused by oxidative stress and impaired antioxidant defense.

Objective

To systematically investigate the markers of oxidative stress and antioxidant systems in the saliva and blood from OLP patients and healthy controls.

Methods

The PubMed, Cochrane Library, and Embase were systematically queried to collect data from studies in which oxidative stress/antioxidant markers from OLP and healthy subjects had been evaluated until March 10, 2021.

Results

A total of 28 studies fulfilled inclusion criteria, and 25 of them, having 849 OLP patients and 1,052 control subjects and analyzing 12 oxidative stress and antioxidant state marker levels, were subjected to meta-analysis. We found a significant decrease in total antioxidant capacity (TAC) and uric acid (UA) and a significant increase in malondialdehyde (MDA) and nitric oxide (NO) levels in the saliva and serum/plasma of OLP patients. Moreover, a significant elevation of 8-hydroxy-deoxyguanosine (8-OHdG) and advanced oxidation protein product (AOOP) level and a decrease in vitamin C were also observed in the saliva of the OLP group. In contrast, salivary vitamin A, zinc, glutathione peroxidase (GPx), vitamin E, and nitrite were not significantly different between the two groups. In single studies, markers of oxidative stresses such as superoxide dismutase (SOD) and 8-isoprostanelevels were elevated in OLP, and antioxidant parameters such as glutathione (GSH) and total protein (TP) levels were dysregulated.

Conclusion

This meta-analysis helps to clarify the profile of oxidative stress and antioxidant state markers in OLP patients although existing evidence is rather heterogeneous and many studies are affected by several limitations. Larger and more standardized studies are warranted to ascertain whether these markers are potential causes or effects of OLP and whether antioxidant therapy improving oxidative stress will be useful.

Oxidative Stress in Cutaneous Lichen Planus-A Narrative Review

Lichen planus (LP) is a chronic, immune-mediated inflammatory skin condition that mainly affects the skin (cutaneous LP, CLP) and oral mucosa (oral LP, OLP). However, the mechanisms involved in the pathogenesis of the disease are not fully elucidated. Over time, several theories that could explain the appearance of LP lesions have been postulated. The key players in LP pathogenesis are the inflammatory infiltrate consisting of T cells and the proinflammatory cytokines. The cytokines stimulate the production of reactive oxygen species that induce cell apoptosis, a defining element encountered in LP. The lead inquiry triggered by this revolves around the role of oxidative stress in LP development. There are currently numerous studies showing the involvement of oxidative stress in OLP, but in terms of CLP, data are scarce. In this review, we analyze for the first time the currently existing studies on oxidative stress in CLP and summarize the results in order to assess the role of oxidative stress in skin lesions offering a fresher updated perspective.