Evaluation of oxidative stress and antioxidant profile in patients with oral lichen planus

Insights into the schizophrenia and dental care: focusing on interaction between implant treatments and oxidative stress

Schizophrenia is a complex mental condition characterized by the deterioration of thought processes and inappropriate emotional responses. Compared to the general population, individuals diagnosed with schizophrenia have an increased risk of developing various dental diseases, including dental caries, periodontal disease, oral mucosal diseases, and conditions associated with oral resonance. In this context, we propose to establish links between schizophrenia and dental illness, emphasizing the importance of oxidative stress (OS) markers in schizophrenia, and also the role of dental treatments, particularly dental implants. This highlights the urgent need for an intervention program to improve oral health in patients with schizophrenia, including aspects such as prevention and prosthetic treatment. Dental implants can be a favorable option, offering good aesthetic and functional results for treated patients with schizophrenia. Additionally, a carefully developed surgical plan is essential, requiring collaboration between psychiatry, oral and maxillofacial surgery, anesthesiology, and prosthodontics departments.

Considering SOD and miRNA analysis as potential prognostic markers in white lesion malignant transformation: A report of two cases

RATIONALE

Predictive biomarkers can be effective in the identification of the oral leukoplakia with an increased probability of malignant transformation.

PATIENTS CONCERNS

A 63-year-old patient presents with persistent burning sensations throughout the oral cavity, accompanied by a white lesion on the tongue. Additionally, a 57-year-old patient with multiple white lesions in the oral cavity.

DIAGNOSIS

Histopathological analysis of the excised tissue.

INTERVENTIONS

Changes in the expression miRNAs (miR17, miR206, and miR23), the activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase), and concentration of reduced glutathione were detected, followed by meta-analysis of previous studies.

OUTCOMES

In both patients (verrucous leukoplakia, oral squamous cell carcinoma) upregulated expression of miR-23a, miR-17, and downregulated expression of miR206 were detected when compared to healthy individuals. In the plasma of a patient diagnosed with carcinoma, higher activity of antioxidant enzymes connected to glutathione was measured in comparison to healthy individuals.

LESSONS

The connection between miRNA expression changes, the increase in glutathione-S-transferase and especially the decrease in superoxide dismutase activities in patients with white lesion potential malignant transformation using the provided statistical analysis was confirmed.

Comparative Assessment of Lipid Peroxidase in Oral Cancer and Oral Potentially Malignant Disorders

Introduction Oral potentially malignant disorders (OPMD) are abnormally altered tissues that could potentially develop into oral cancer. From the literature, it is understandable that not all OPMDs develop into oral cancer. Hence, it is essential to identify the high-risk lesions that are more likely to develop into oral cancer. Lipid peroxidase (LPO) is a byproduct of phospholipid metabolism, and its levels are an oxidative stress marker that can probably help us predict the onset of cancer in OPMDS. This study aimed to assess the levels of LPO in OPMD, oral cancer, and normal patients. Materials and methods The sample size estimated was 15 per group. There were four groups in total. The estimation was done with the Abbkine LPO enzyme-linked immunosorption assay (ELISA) kit (Atlanta, Georgia, USA). An enzyme-substrate reaction was carried out, and the degree of the color change was measured using a microplate reader. The values were tabulated, and statistics were carried out using Statistical Package for Social Sciences (SPSS) version 26.0 (IBM Corp., Armonk, NY, USA). Both descriptive and inferential statistics were carried out. Results LPO levels (nmol/L) in each of the four groups were as follows: Group 1 (oral cancer): 171.86±78.86, Group 2 (controls): 71.66±28.36, Group 3: (oral leukoplakia): 127.50±103.53, and Group 4 (oral submucous fibrosis and oral lichen planus): 100.39±41.06. The results, when compared, were statistically significant (P< 0.05). Discussion From the above results, it is understandable that oral cancer patients experience increased oxidative stress compared to the OPMD group. The current study concluded that the obtained results showed differences in LPO levels, suggesting LPO could be used as a marker and screening tool to assess the rate and severity of cellular damage in patients with oral potentially malignant disorders.

Difference in immune responses to Candida albicans in two inbred strains of male rats

OBJECTIVE

To investigate the influence of strain differences in immune response on the pathogenesis of oral candidiasis in Dark Agouti (DA) and Albino Oxford (AO) inbred strains of rats.

DESIGN

Seventy male 8-weeks old DA and AO rats were inoculated with Candida albicans to induce three different experimental models of oral candidiasis, one immunocompetent and two immunocompromised models. The animals were sacrificed after 16 days from the beginning of the experiment followed by collecting the samples of the tongue dorsum and blood for histopathological (PAS and H&E staining), immunohistochemical, qRT-PCR, and oxidative stress analyses.

RESULTS

Histopathological and immunohistochemical analyses revealed lower levels of epithelial colonization, epithelial damage, and inflammatory infiltration in DA compared to AO strain of rats. DA rats had fewer CD45, CD68, and CD3 positive cells but more HIS 48 positive cells than AO rats. The expressions of IL-1β, TNFα, IFN-γ, IL-10 and TGF-β1 were consistently higher in DA strain across all experimental models. However, the expressions of IL-4 and IL-17 differed inconsistently between DA and AO strain in various experimental models. Strain differences were observed in levels of prooxidative hydrogen peroxide and lipid peroxidation, with higher levels presented in AO rats compared to DA rats, while antioxidative parameters presented little yet inconsistent difference between strains.

CONCLUSION

DA strain of rats consistently presented lower susceptibility to oral infection with C. albicans compared to AO strain with robust Th1/Th17 immune response indicating the importance of the genetic background on the development of oral candidiasis.

Quality-by-Design R&D of a Novel Nanozyme-Based Sensor for Saliva Antioxidant Capacity Evaluation

Oxidative stress is one of the main causes of cell damage, leading to the onset of several diseases, and antioxidants represent a barrier against the production of reactive species. Saliva is receiving increasing interest as a promising biofluid to study the onset of diseases and assess the overall health status of an individual. The antioxidant capacity of saliva can be a useful indicator of the health status of the oral cavity, and it is nowadays evaluated mainly through spectroscopic methods that rely on benchtop machines and liquid reagents. We developed a low-cost screen-printed sensor based on cerium oxide nanoparticles that can be used to assess the antioxidant capacity of biofluids as an alternative to traditional methods. The sensor development process was investigated via a quality-by-design approach to identify the most critical parameters of the process for further optimization. The sensor was tested in the detection of ascorbic acid, which is used as an equivalent in the assessment of overall antioxidant capacity. The LoDs ranged from 0.1147 to 0.3528 mM, while the recoveries varied from 80% to 121.1%, being therefore comparable with those of the golden standard SAT test, whose recovery value was 96.3%. Therefore, the sensor achieved a satisfactory sensitivity and linearity in the range of clinical interest for saliva and was validated against the state-of-the-art equipment for antioxidant capacity evaluation.

Emerging potential of phototherapy in management of symptomatic oral lichen planus: A systematic review of randomised controlled clinical trials

Phototherapy incorporating photobiomodulation therapy and antimicrobial photodynamic therapy has been utilised as antioxidants in symptomatic oral lichen planus (OLP) management; however, its role of intervention remains controversial. The aim of this systematic review of CRD42021227788 PROSPERO (an international prospective register of systematic reviews in health and social care) registration number was to oversee and determine phototherapy efficacy in patients with symptomatic OLP, identifying and bridging the literature gaps by proposing recommendations for future studies. A search strategy was developed in consistent with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Various electronic databases were exercised to search for randomised controlled clinical trials (RCTs). Several search engines were employed to analyse a total of 177 studies of which nine included. A wide range of utilised laser and light-emitted diode wavelengths between 630 and 808 nm and irradiance ranged between 10 and 13 mW/cm² were noted. 67% of studies reported a high risk of bias and a high heterogeneity obtained from numerical data for quantitative analysis, therefore meta-analysis was impossible to conduct. Despite inconsistency and diversity in phototherapy parameters, treatment protocols, photosensitiser (type, concentration and method of application) and outcome assessment tools, the majority of the studies showed positive results compared with standard care treatments. Hence, a necessity to perform well-designed RCTs with robust methodology is warranted, after acknowledging the current drawbacks and addressing the suggested recommendations highlighted in our review. Moreover, advanced knowledge in understanding further phototherapy-antioxidants molecular mechanistic in symptomatic OLP is required.

Salivary Antioxidant Profile in Patients with Systemic Sclerosis and Periodontitis

Objective

The aim of the present study was to compare periodontal status and antioxidant profile in unstimulated saliva of systemic sclerosis (SSc) patients with periodontitis and systemically healthy periodontitis patients.

Design

Twenty patients with established diagnoses of systemic sclerosis and periodontitis (SSc group) and 20 systemically healthy individuals with periodontitis (P group) were enrolled in the study. Clinical periodontal parameters (clinical attachment level (CAL), gingival recession (GR), periodontal probing depth (PPD), and gingival index (GI)) and concentration of uric acid (UA), superoxide dismutase (SOD), and glutathione peroxidase (GPX) in unstimulated saliva samples were assessed.

Results

There were significantly higher mean values of CAL (4.8 ± 0.21 mm versus 3.18 ± 0.17 mm; p ≤ 0.001) and GR (1.66 ± 0.90 mm versus 0.46 ± 0.54 mm; p ≤ 0.001) in the SSc group when compared to the P group. Significantly higher level of GPX (p ≤ 0.001) and SOD (p ≤ 0.001) in unstimulated saliva was detected in the SSc group in comparison with the P group. The specific activity of UA did not significantly differ between the two groups (p = 0.083).

Conclusion

The results may indicate higher periodontal destruction and antioxidant perturbations in unstimulated saliva of SSc patients with periodontitis compared to systemically healthy periodontitis patients.

Mechanisms of reactive oxygen species in oral lichen planus: A literature review

Oral lichen planus is a chronic non-infectious mucosal inflammatory disease caused by an imbalance between reactive oxygen species homeostasis and antioxidant defense systems. Notably, excessive oxidative stress products result in related autoimmune reactions. Further, it activates signaling pathways related to the development of oral lichen planus, as evidenced by the detection of damage to deoxyribonucleic acid, protein, and lipid. Thus, the mechanisms of reactive oxygen species-mediated oxidative stress in the pathogenesis of oral lichen planus are numerous and complex. In this review, we first introduce oxidative stress and oxidative products. Then, we summarize the role and possible mechanisms of reactive oxygen species-mediated oxidative stress in the pathogenesis of oral lichen planus and present a clinical correlation between oxidative stress and oral lichen planus. Finally, we discuss the current challenges and future perspectives.

Antioxidant effect of chamomile tea on the salivary glands of streptozotocin-induced diabetic rats

This study aimed to analyze oxidative stress and the activity of antioxidant enzymes in the salivary glands of streptozotocin (STZ)-induced diabetic rats with ad libitum consumption of chamomile tea in substitution of water for 21 days. Rats were divided in two control groups (untreated control and treated control) and two diabetic groups (untreated diabetic and treated diabetic). Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activities, total antioxidant status (TAS), and malondialdehyde (MDA) concentrations were determined. The chemical composition of the chamomile essential oil revealed 39 compounds, accounting for 93.5% of the total oils. The polyphenolic profile of the tea showed the presence of apigenin, luteolin, umbelliferone, and esculetin. SOD, GPx, CAT, and TAS levels were lower in the parotid (PA) diabetic glands, but treatment increased their concentration in both the submandibular (SM) and PA diabetic salivary glands. Increased MDA levels were observed in the PA diabetic glands, which were decreased by the consumption of chamomile tea with a reduction in hyperglycemia compared to that in untreated diabetic rats. However, the SM diabetic glands showed no difference in the MDA content. The consumption of chamomile tea prevented oxidative stress in the PA glands of diabetic rats, exhibiting hypoglycemic and antioxidant effects. Thus, chamomile tea could be a potential candidate for preventing oral complications in diabetes mellitus.

Cathepsin-B and caveolin-1 gene expressions in oral lichen planus and oral squamous cell carcinoma

BACKGROUND

Given the importance of the role of cellular changes in the prognosis and diagnosis of malignancies of the head and neck, we examined in this study the gene expressions of cathepsin-B (Cat-B) and caveolin-1 (Cav-1) which are in cell membranes structures involved in carcinogenesis, in oral squamous cell carcinoma (OSCC) and oral lichen planus (OLP) and compared them to controls. We also investigated their relationship to clinicopathological indices.

METHODS AND RESULTS

In this case-control study, 29 paraffin blocks of OLP patients were compared to 29 paraffin blocks of OSCC samples as well as 28 paraffin blocks of normal oral tissue. Real-time quantitative PCR was performed to determine gene expressions and results were analyzed for their relationship to clinical data using chi-square, Kruskal-Wallis and Mann-Whitney tests.

RESULTS

The mean age of OSCC and OLP patients were 59.24 ± 15.04 and 48.79 ± 14.17 years, respectively. The Cat-B and Cav-1 expressions were significantly higher in OSCC and OLP samples compared to control (p < 0.001). The highest expression was found in OSCC samples. The difference between OLP and control samples for Cat-B and Cav-1 expression was significant. There was no association between the gene expression and age, gender, duration of disease, Thongprasom score, smoking and cutaneous lichen planus. However, the expressions were related to the grade and stage of OSCC samples (P = 0.01, P = 0.02).

CONCLUSION

The gene expressions of Cat-B and Cav-1 in OSCC were associated with the stage and grade of lesions. Therefore, they appear to be useful in predicting the biological behavior of OSCC and malignant transformation of OLP, although this process is multi factorial and more investigations are needed.

Evaluation of salivary oxidative stress in oral lichen planus using malonaldehyde

Background:

Oral lichen planus is a chronic, mucocutaneous, inflammatory disease, with an unknown etiology. Reactive oxygen species and oxidative damage to the tissues might be the cause. Malonaldehyde (MDA), a low molecular weight end product of lipid peroxidation reaction is a suitable biomarker of endogenous DNA damage. monitoring the oxidant-antioxidant status of saliva may serve as an efficient marker of disease development in oral lichen planus patients.

Aim and Objectives:

To evaluate salivary oxidative stress in oral lichen planus subject using MDA and compare it with control subjects. Furthermore, to compare MDA levels in erosive and hypertrophic lichen planus.

Materials and Methods:

The current study is case–control study. Unstimulated salivary samples in the morning hours were taken from oral lichen planus subjects (n = 25) and controls subjects without any oral disease (n = 25). The saliva was centrifuged at 900 g for 10 min at a temperature of 4°C. Then, the entire filtrate was transferred to Eppendorf test tubes and frozen at–80°C until analysis. Salivary MDA was done through thiobarbituric acid reactive substance assay as per the protocol laid down by the manufacturer (Sigma Aldrich Lipid Peroxidation Assay Kit).

Results:

The data were expressed as the mean ± standard deviation and the statistical analysis was done using Student's t-test using SPSS version 21 IBM software. The salivary level of MDA was significantly higher than that of controls (P < 0.05).

Conclusion:

The higher level of MDA in patients with oral lichen planus suggests that free radicals and the resulting oxidative damage may be important in the pathogenesis of oral lichen planus lesions.

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.

Markers associated with malignant transformation of oral lichen planus: A review article

Oral lichen planus (OLP) is one of the autoimmune diseases associated with chronic inflammation that involves several complications including the potential for malignant transformation into oral squamous cell carcinoma. Pathogenesis of OLP are yet to be fully comprehended however, it has been demonstrated that the epithelial cells in OLP lesions are affected by cytotoxic T lymphocytes leading to immunological reactions. Various factors are reported to act as diagnostic markers for predicting and monitoring the cancerous progression. Hence, in this review, we summarize and present the latest studies regarding the predictive markers associated with malignant potential of OLP.

New markers of oxidative stress in lichen planus and the influence of hepatitis C virus infection - a pilot study

INTRODUCTION

Lichen planus (LP) is a mucocutaneous T-cell mediated disorder of unknown etiology. There is growing evidence that oxidative stress is an important player in the pathogenesis of LP. Therefore, we have investigated oxidative stress markers in LP and the influence of hepatitis C virus (HCV) infection, a frequently associated condition, on oxidative stress in LP patients.

METHOD

We have determined the serum levels of 4- hydroxynonenal (4-HNE) and symmetric dimethylarginine (SDMA), as markers of oxidative stress, and total antioxidant capacity (TAC), as a marker of the antioxidant defence, in 4 groups: group A - HCV positive patients with LP (n=12), group B - HCV positive patients without LP (n=12), group C - HCV negative patients with LP (n=31) and group D - control group (n=26).

RESULTS

In LP patients, we have identified an increased level of lipid peroxidation (4-HNE - group A - 8.41±1.11 µg/mL, group B - 7.97±2.17 µg/mL, group C - 7.81±1.96 µg/mL and group D - 6.15±1.17 µg/mL) and alterations in arginine methylation (SDMA - group A - 1.10±0.24 µmol/L, group B - 1.03±0.16 µmol/L, group C - 0.84±0.19 µmol/L and group D - 0.50±0.06 µmol/L) associated with a diminished antioxidant defence (TAC - group A - 234,50±49,96, µmol/L group B - 255,83±41,41 µmol/L, group C - 269,83±43,33 µmol/L and group D - 316,46 ±29,33 µmol/L), processes augmented by the association with HCV infection.

CONCLUSION

There is an imbalance between oxidants and antioxidants in patients with LP, an imbalance that is augmented by the presence of HCV infection. SDMA could be regarded as a novel biomarker of oxidative stress among these patients. To the best of our knowledge this is the first study to investigate the influence of HCV infection on oxidative stress in LP patients.

Erosive oral lichen planus inflicts higher cellular stress than reticular type

BACKGROUND

Lichen planus is a chronic inflammatory mucocutaneous disease which frequently involves the oral mucosa. The most common types of oral lichen planus (OLP) are reticular (asymptomatic) and erosive (ulcerative) with malignant potentiality. The aims of the present study are to assess the cellular stress level in both types of OLP lesions with respect to oxidative stress, DNA damage and inflammation.

MATERIALS AND METHODS

Freshly diagnosed untreated 25 OLP reticular type and 25 OLP erosive (OLP-E) type patients aged 35-55 years were enrolled in the study along with age and sex-matched 25 healthy subjects as control. Tissue antioxidant enzymes were measured biochemically, single-cell DNA damage was measured by comet assay and the molecular markers for inflammation were assessed by using semi-quantitative reverse transcriptase-polymerase chain reaction. Statistical analyses were performed using one-way ANOVA and Tukey's post hoc test.

RESULTS

Oxidative stress was significantly greater in OLP-E type compared to the reticular. mRNA expression of cyclooxygenase-2 was significantly elevated (P < 0.0001) in erosive form, but such expression of nuclear factor kappa beta, tumor necrosis factor-alpha, Interleukin-6 and inducible nitric oxide synthase did not significantly differ between the two disease groups. Comet assay revealed a higher degree of DNA strand breakage in erosive lesions.

CONCLUSIONS

The unhandled free radicals may imbalance the homeostatic network toward pro-inflammatory, DNA damaging responses, creating a vicious cell-damaging spree resulting in stress. Molecular analyses showed that erosive lichen planus is more under stress than the reticular form.

Patch test of dental materials in Oral Lichen Planus with considering the role of saliva

Lichen planus is the most common skin disease that affects the oral mucosa. Oral Lichen Planus is a T-cell-mediated autoimmune disorder. In the current study, for the first time, an oral cavity condition in skin patch tests with adding saliva is simulated. In addition, the patch results are compared with healthy subjects. Forty-one OLP patients and 63 healthy subjects were enrolled in the study. All participants were provided with patch tests, including allergens, in combination with saliva in chambers. Allergens from the European baseline (standard) series selected according to the most prevalent positive results in the previous study were applied. Positive results of Mercury and Cobalt tests were significantly higher in the case group. In this study, the differentiation of patients with lichen planus and lichenoid was identified according to the Van der Meij & Van der Waal criteria. The patch test was conducted for healthy individuals as well. The most important of all was the use of patients' saliva in the patch test, done for the first time in this field. In the case of OLP, a patch test can help identify positive reactions to dental materials; thus, the replacement of dental restorations may be needed.

Oral Lichen Planus - Related Connection with HLA-System Antigens

AIM

To determine whether there is an immunogenic connection and antigen difference between the HLA antigens in the erosive (EOLP) and reticular (ROLP) oral lichen planus.

MATERIALS AND METHOD

73 patients with ROLP and EOLP have been tested. Typing of the HLA antigens has been made for locus A and B. The typing of the HLA was conducted with the use of microlymphocyto toxic test by Terasaki. The reading of the findings has been conducted with an inverse microscope. When a reaction has 4 points it is considered to be positive.

RESULTS

The most frequently typified antigens in ROLP from locus A are HLA А2 (57.57%) and А3 (33.33)%, and for locus B 21.21%. In EOLP it is А9 (8888%). In locus B a connection has been found with HLA B8 (77.77%). The statistical analysis with the ×2 test has shown that the carriers of HLA A9 display a relative risk (RR) of 3.65 and ×2=20.72. Consequently, there is high static importance for locus A p<0,001. For locus B, In EOLP for HLA B8, RR=6. 7 ×2=37.64 and p<0,001. ROLP has shown association with HLA A3, where RR=2. 31 and ×2 =9.14 and p<0.05.

CONCLUSIONS

In ROLP A3 antigen and in EOLP A9 and A8 may be considered as carriers with proneness to OLP.

Micronutrients Profile in Oral Lichen Planus: a Review Literature

Oral lichen planus (OLP) is a relatively common chronic inflammatory disease. The micronutrients are critical factors in health of oral mucous and proper function of immune system. There have not been any review articles for evaluating trace element levels before and after standard treatments of OLP. The purpose of this study is to provide complete review of the association of micronutrients with OLP. Databases including PubMed, Google Scholar, Scopus, and Embase (Ovid) with keywords of oral lichen planus, OLP, oral disorder, micronutrients, trace element, nutrient element, antioxidant, oxidative stress, malnutrition, and essential trace elements, without time limitation (1900-2019) were searched to collect data on related articles. Total number of 58 original articles including 12 randomized clinical trials, 41 case-control, 4 case reports, and 1 cell line research were reviewed in this study. Lower levels of iron and its associated markers, such as hemoglobin and ferritin, increased levels of TIBC; reduced levels of zinc, calcium, vitamin D, vitamin B12, folic acid, and antioxidants such as vitamins C and E; and increased levels of oxidants and homocysteine, have been reported in OLP patients.

Evaluation of Salivary and Serum Total Antioxidant Capacity and Lipid Peroxidation in Postmenopausal Women

Objective

In menopause, reduction of estrogen hormone affects oxidative stress process in serum. Oxidative stress in saliva plays a significant role in the pathogenesis of oral diseases. The aim of this study was to investigate the total antioxidant capacity and lipid peroxidation in the serum and saliva of premenopausal and postmenopausal women.

Methods

In this case control study, 50 postmenopausal women (case group) and 48 premenopausal women (control group) were selected. The unstimulated whole saliva and serum of the postmenopausal and premenopausal women were collected. The total antioxidant capacity (TAC) of the saliva and serum was measured by ferric reducing antioxidant power (FRAP). Also, malondialdehyde (MDA) was measured by thiobarbituric acid reactive substance (TBARS) method for serum and saliva. Then, the obtained data were analyzed by SPSS 17, whereby Mann–Whitney test and Spearman's correlation test were used. P < 0.05 was considered statistically significant.

Results

The postmenopausal group had significantly lower mean serum TAC and higher mean serum MDA than the control group (P < 0 < 001 and P < 0.01, respectively). The mean salivary TAC and MDA, however, did not differ significantly between the case and control group (P = 0.64 and P = 0.08, respectively).

Conclusion

In postmenopausal women, with elevation of serum MDA and reduction of serum TAC, the extent of serum oxidative stress grows, but MDA and TAC levels of saliva do not change.

Assessment of salivary thioredoxin levels in oral lichen planus and oral squamous cell carcinoma

OBJECTIVE

Oral lichen planus (OLP) is a chronic mucocutaneous inflammatory disease, which is considered as a potentially malignant condition and could transformed into oral squamous cell carcinoma (OSCC). Squamous cell carcinmoma is the most common oral cancer. This study aimed to compare salivary thioredoxin levels as an antioxidant protein among patients with OSSC, OLP and healthy subjects.

MATERIALS AND METHODS

Twenty-eight patients with OLP, 20 patients with OSCC and 40 healthy people enrolled in this observational study. Saliva samples were collected from all subjects and salivary thioredoxin levels were evaluated by Elisa test. The data were recorded in the check lists and analyzed using SPSS (ver.17).

RESULTS

Thioredoxin levels of healthy controls were insignificantly higher than OLP and SCC patients (p = 0.135). There was a statistically remarkable indirect relationship between thioredoxin levels and severity of the lesions determined by Thongprasom criteria among OLP patients. The thioredoxin concentration was significantly higher in the keratotic OLP. Among the OSCC patients, the highest levels of thioredoxin were found among patients aged more than 65 years. Salivary thioredoxin levels based on other variables were not significantly different between the studied groups.

CONCLUSION

In this study, there was not any significant difference between salivary thioredoxin levels in the OLP and OSCC patients, though it was unremarkable higher in the healthy group compared to the patients; therefore, the role of thioredoxin in the cellular oxidation-reduction status could be suggested; however, further studies are recommended.

Potential Metabolic Biomarkers for Early Detection of Oral Lichen Planus, a Precancerous Lesion

Background: Oral lichen planus (OLP) is a T-cell-mediated chronic inflammatory disorder and precancerous oral lesion with high incidence. The current diagnostic method of OLP is very limited and metabolomics may provide a new approach for quantitative evaluation.

Methods: The Ultra-Performance Liquid Chromatography-Quadrupole/Orbitrap High Resolution Mass Spectrometry (UHPLC-Q-Orbitrap HRMS) was applied to analyze the change of metabolites in serum of patients with OLP. A total of 115 OLP patients and 124 healthy controls were assigned to either a training set (n = 160) or a test set (n = 79). The potential biomarkers and the change of serum metabolites were profiled and evaluated by multivariate analysis.

Results: Totally, 23 differential metabolites were identified in the training set between OLP group and healthy group. Three prominent metabolites in receiver operating characteristic (ROC) were selected as a panel to distinguish OLP or healthy individuals in the test set, and the diagnostic accuracy was 86.1%.

Conclusions: This study established a new method for the early detection of OLP by analyzing serum metabolomics using UHPLC-Q-Orbitrap HRMS, which will help in understanding the pathological processes of OLP and identifying precancerous lesions in oral cavity.

Diagnostic Criteria of Oral Lichen Planus: A Narrative Review

Oral lichen planus (OLP) is a disease with unclear etiology or pathogenesis, categorized by the World Health Organization as oral lichenoid lesions (OLL; interface mucositis or lichenoid mucositis) into a group of potentially malignant disorders. The diagnosis of OLP is challenging because the clinical and histopathologic features are frequently seen in OLP, OLL and/or other mucosal diseases with lichenoid characteristics. Furthermore, OLP has a dynamic nature. Finally, an early and precise diagnosis can play a decisive role, allowing timely treatment and thus improving the patient quality of life. This article summarizes the state-of-the-art regarding OLP and OLL and discusses the challenges faced on making an accurate diagnosis, aiming to provide a practical guideline for the postgraduates and oral physicians in reaching the diagnosis of these lesions.

Expression profile of DNA repair proteins and histone H3 lys-9 acetylation in cutaneous and oral lichen planus

OBJECTIVES

To analyze the expression profile of DNA repair proteins (XRCC1 and APE1) and histone acetylation (H3K9) in oral and cutaneous lichen planus, in order to investigate potential biological markers that can clarify pathogenesis of these lesions.

DESIGN AND RESULTS

The total sample consisted of 89 lichen planus cases (66 oral and 23 cutaneous). Analysis of APE1 and XRCC1 expression was performed by immunohistochemistry in 44 oral and 20 cutaneous lichen planus, whereas the analysis of H3K9 acetylation was performed by immunofluorescence in 42 oral and 11 cutaneous lichen planus.

RESULTS

Immunoreactivity for APE1 and XRCC1 was significantly higher in cutaneous lichen planus than in oral lichen planus (P = 0.003 and P = 0.034, respectively). There was a significant and moderate positive correlation between APE1 and XRCC1 in the oral group (Rho = 0.544; P < 0.0001). In oral cases, there were no statistically significant results comparing APE1 and XRCC1 expression between reticular and erosive cases (P > 0.05). Evaluation of H9K3 histone acetylation levels did not reveal significant results comparing oral to cutaneous lichen planus, neither comparing erosive to reticular (P > 0.05).

CONCLUSIONS

Changes in the expression profile of the DNA repair proteins exerted greater influence in pathogenesis of cutaneous lichen planus than oral lichen planus, in addition, H3K9 histone acetylation is an epigenetic event found in both lesions.

Urinary metabolomic signatures in reticular oral lichen planus

Oral lichen planus (OLP) is a chronic inflammatory disease. Among all the clinical forms in OLP, reticular type has the highest incidence rate. Previous studies have applied metabolomics to investigate the metabolic changes of oral mucosa and blood samples from reticular OLP patients. Urinary metabolomic signatures is also useful in analyzing the pathological changes of the patients, which was a complement to the previous studies. Through these researches, we may have a more comprehensive understanding of the disease. Metabolic profiles of urinary samples from OLP patients and control subjects were analyzed by liquid chromatography (LC)-mass spectrometry (MS) system. Differentially expressed metabolites were identified via OSI/SMMS software for the pathology analysis. Totally, 30 differentially expressed metabolites were identified. Pathological network showed that these metabolites participated in 8 pathological processes, that is, DNA damage and repair disorder, apoptosis process, inflammatory lesion, oxidative stress injury, carbohydrate metabolism disorder, mood dysfunction, abnormal energy expenditure, and other pathological process. These findings demonstrated that the analysis of human urine metabolome might be conducive to the achievement of the objectives of this study.

Association of nitric oxide with oral lichen planus

BACKGROUND

The small signalling molecule nitric oxide (NO) has been postulated to have a mediator role in the pathogenesis of several diseases including oral lichen planus (OLP). This systematic review aimed to quantify the existing literature and assess the association of NO and OLP.

METHODS

The focused question being addressed was "Is there an association between nitric oxide and OLP?" PubMed, EMBASE, Scopus, and Web of Science, and grey literature from January 1990 to August 2018 were searched. Two independent reviewers performed the study selection using specified eligibility criteria.

RESULTS

Seven studies that met the eligibility criteria were included. All of these were case-control studies and 151 patients with OLP were evaluated (mostly females), with an age ranged from 20 to 75 years. The included studies showed a significant higher NO levels in OLP patients compared to the healthy controls, with two studies demonstrated a higher NO levels in erosive OLP compared to non-erosive OLP.

CONCLUSION

These findings support that an association exists between higher NO concentration and OLP. However, larger high-quality studies with refined methodological design are needed to confirm the role of NO in the aetiology and pathogenesis of OLP.

Serum-based metabolomics characterization of patients with reticular oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) is a chronic inflammatory mucosal lesion and systemic disease. In OLP, reticular type is the most common presentation of the disease. However, little is known about it. The aim of this study was to analyze the pathogenesis of reticular OLP and its possible associations with the pathological changes in other organ systems through serum-based metabolomics.

METHODS

Blood samples were obtained from 16 reticular OLP patients and 24 control subjects. Liquid chromatography (LC)-mass spectrometry (MS) system was used to identify differentially expressed metabolites. The pathways analysis was performed by MetaboAnalyst. Pathological network was constructed by Cytoscape software.

RESULTS

Totally, 31 modulated metabolites were identified, whose dysregulations affected 25 metabolic pathways and 7 pathological processes in the disease. Through an impact-value screen (impact-value＞0.1), 6 pathways were selected as the significantly dysregulated pathways. Pathological network showed that these metabolites participated in 7 pathological processes, that is, apoptosis process, DNA damage and repair disorder, oxidative stress injury, carbohydrate metabolism disorder, mood dysfunction, inflammatory lesion, and other pathological process.

CONCLUSION

The study demonstrated that reticular OLP could cause the dysregulations of the metabolites in serum, which might be also further linked to other organ and systemic diseases through the blood system, such as diabetes, sleep disorders, and depression, etc.

Metabolomics analysis of oral mucosa reveals profile perturbation in reticular oral lichen planus

BACKGROUND

Oral lichen planus (OLP) is a chronic inflammatory mucosal disorder and potentially oral premalignant lesion affecting the stratified squamous epithelia. In OLP, reticular type is the most common clinical form of the disease. However, little is known about it. Metabolomics analysis may help to investigate the disease pathogenesis and to improve clinical treatment.

METHODS

Liquid chromatography (LC)-mass spectrometry (MS) system, XCMS software, SIMCA software, and OSI / SMMS software were integrated to identify differentially expressed metabolites for the pathways and pathology analysis.

RESULTS

Totally, 21 modulated metabolites were identified, whose dysregulations affected 30 metabolic pathways. Through an impact-value screen (impact-value>0.1), 8 pathways were selected as the significantly dysregulated pathways. Pathological network showed that these metabolites participated in 5 pathological processes, that is, inflammatory lesion, DNA damage and repair disorder, apoptosis process, oxidative stress injury, and abnormal energy expenditure.

CONCLUSION

The study revealed the metabolic perturbation of oral mucosa in reticular OLP, which may provide an important reference for the understanding of the pathogenesis of the disease and the discovery of therapeutic targets.

Critical appraisal of the oxidative stress pathway in vitiligo: a systematic review and meta-analysis

BACKGROUND

The pathogenesis of vitiligo remains a topic of extensive debate. This is partly due to the moderate efficacy of current treatments. The role of the oxidative stress pathway in vitiligo is a popular although controversial research topic.

OBJECTIVE

To clarify the role of the oxidative stress pathway in vitiligo compared to other inflammatory skin disorders and to assess the therapeutic role of antioxidants.

METHODS

We conducted a systematic search of the existing literature on the aberrancies of the oxidative stress pathway in vitiligo. Subsequently, the efficacy of both topical and oral antioxidants in clinical trials was investigated.

RESULTS

A deregulated oxidative pathway is clearly evident with elevated superoxide dismutase, decreased catalase and increased lipid peroxidation. However, similar results have been obtained in other inflammatory skin diseases such as psoriasis, atopic dermatitis, lichen planus and urticaria. This questions the unique role of oxidative stress in the development of vitiligo. Some isolated successes have been reported with oral ginkgo biloba, polypodium leucotomos and vitamin C and E preparations, while other clinical trials have failed to show reproducible results. The use of topical antioxidants delivers in general no beneficial results.

CONCLUSION

The oxidative pathway is affected in vitiligo, but its unique initiating or contributory role in the pathogenesis is less evident. Interesting data support the added value of oral antioxidants in vitiligo although confirmatory studies are missing.

Salivary Antioxidant Status in Patients with Oral Lichen Planus: Correlation with Clinical Signs and Evolution during Treatment with Chamaemelum nobile

Oral lichen planus (OLP) is a chronic inflammatory mucocutaneous disease, which manifests as a succession of outbreaks. OLP was associated with salivary oxidative stress. Randomized, double blind, parallel-group study was performed. The sample consisted of 55 clinically and histopathologically diagnosed OLP patients. Twenty-six patients were treated with 2% Chamaemelum nobile gel and 29 with a placebo. Nonstimulated (basal) saliva was collected on the first day of the study and 4 weeks later. Salivary total antioxidant status (TAS) was evaluated by four different methods: two TAC (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) equivalent antioxidant capacity methods (TAC1 and TAC2), cupric reducing antioxidant capacity (CUPRAC), and ferric reducing ability of plasma (FRAP). At baseline (T1), no statistically significant differences were detected in any of the TAS analytes between the two groups of patients. After four weeks of treatment, a statistically significant increase was detected in FRAP in the placebo group (0.323 [0.090-0.467] versus 0.406 [0.197-0.848] mmol/g⁎10^-3) (P < 0.05). Significant correlations were observed between pain and drainage and TAC1, CUPRAC, and FRAP and between xerostomia and the TAC1, TAC2, CUPRAC, and FRAP. The results of the present study showed that in patients with OLP increases of TAS in saliva are associated with increase in pain and xerostomia and decrease in drainage, suggesting a worsening condition of the patient. The use of Chamaemelum nobile gel would be recommended for disease stabilization.

Xerostomia and Salivary Gland Hypofunction in Patients with Oral Lichen Planus Before and After Treatment with Topical Corticosteroids

BACKGROUND

Oral lichen planus and mouth dryness are common pathoses, yet not entirely understood. These two conditions may be associated, with a few studies investigating the relationship between mouth dryness and oral lichen planus providing conflicting results. None of the studies have explored the specific impact of disease treatment on mouth dryness.

OBJECTIVE

The purpose of this observational before and after comparison study was to examine the effect of treatment of oral lichen planus with topical corticosteroids on mouth dryness.

METHODS

Nineteen subjects with oral lichen planus were evaluated for the severity of xerostomia using a xerostomia inventory and a visual analogue scale. Stimulated and unstimulated whole salivary flow rates, unstimulated salivary pH and buffering capacity were also measured. All subjects were evaluated before and after treatment with topical corticosteroids.

RESULTS

All subjects reported xerostomia before treatment with topical corticosteroids, with 79% reporting a significant improvement (P = 0.03) after treatment. Topical corticosteroid treatment was not associated with statistically significant differences in stimulated or unstimulated salivary flow rates, unstimulated salivary pH or buffering capacity.

CONCLUSION

The results of this study suggest that treatment of oral lichen planus with topical corticosteroids may decrease the severity of dry mouth symptoms.

Salivary changes in oral mucosal diseases

Saliva is a unique biological fluid that can be easily collected and analyzed with low cost and low morbidity. Therefore, there is a growing attention for using salivary biomarkers in the diagnosis and monitoring of disease progress and response to treatment. Salivary changes have been described in relation to oral mucosal diseases. This article discusses the causes and consequences of salivary hypofunction and presents a review of the literature related to changes in salivary parameters in various oral mucosal diseases and in systemic diseases with possible oral mucosal involvement.

Ascorbic acid deficiency in patients with lichen planus

OBJECTIVES

Recent studies have highlighted the role of oxidative stress in the pathogenesis of lichen planus (LP). In the present study, the interest of the authors is focused on the investigation of ascorbic acid status in patients with LP and identification of parameters that might influence the level of this vitamin.

MATERIAL AND METHOD

We analyzed the level of urinary ascorbic acid (reflectometric method) in 77 patients with LP (cutaneous LP (CLP)-49 cases; oral LP (OLP)-28 cases) and 50 control subjects. The evaluation of all participants included clinical examination and laboratory and imaging tests.

RESULTS

Compared to the control group (19.82 mg/dl) the level of ascorbic acid was significantly lower both in patients with CLP (8.47 mg/dl, p = 0.001) and in those with OLP (8.04 mg/dl, p = 0.001). In patients with LP it was found that the deficiency of ascorbic acid increases with age (r = -0.318, p = 0.032). The urinary concentrations of ascorbic acid were significantly lower in patients with LP associated with infections compared to patients with LP without infections.

CONCLUSIONS

The urinary ascorbic acid level may be a useful parameter in identifying patients with LP who are at risk of developing viral or bacterial infections.

Analysis of human serum metabolome for potential biomarkers identification of erosive oral lichen planus

BACKGROUND

Oral lichen planus (OLP) is a chronic auto-inflammatory mucositis and potentially oral premalignant lesion. Erosive OLP patients display the higher canceration rate as compared to the patients with non-erosive OLP. Identification of the potential biomarkers associated with erosive OLP may help to investigate the disease pathogenesis and to improve clinical treatment.

METHODS

Ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF-MS) combined with pattern recognition approaches were integrated to acquire differentially expressed metabolites for the pathways analysis and elucidate mechanisms of disease.

RESULTS

Totally, 10 modulated metabolites were characterized as the potential biomarkers of erosive OLP, whose dysregulations could affect multiple metabolic pathways and pathological processes in the disease.

CONCLUSION

These findings indicated that the analysis of human serum metabolome might be conducive to the achievement of the objectives of this study.

Evaluation of oxidative stress markers in oral lichen planus

Background

Lichen planus (LP) is a chronic, inflammatory disease that affects the skin, mucous membrane, scalp and nails that frequently involves the oral mucosa. Oxidative stress reflects an imbalance between the production of reactive oxygen species and the biological system's ability to readily detoxify the reactive intermediates or repair the resulting damage. It has been suggested that oxidative stress may play a role in the pathogenesis of LP.

Aim and Objectives

To evaluate the role of oxidative parameters in the pathogenesis of oral LP, estimate the levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GPx) and uric acid (UA) in saliva of oral LP patients and to compare the levels of SOD, MDA, GP and UA in oral LP patients with healthy controls.

Methodology

In this cross-sectional study, 1.5 ml of fasting saliva sample was collected using passive drool method from the study group (30 patients diagnosed as having oral LP) and the control group (30 age-matched healthy volunteers). The unstimulated saliva was collected were analyzed by spectrophotometry. Statistical analysis was done to evaluate and compare the values between groups.

Results

The mean values of SOD and MDA in saliva in the study group showed a significant increase in amount when compared with the control group whereas GPx showed a significant decrease in the study group. UA value showed an insignificant difference in the same comparison.

Interpretation and Conclusion

Oxidative stress markers as MDA and SOD are elevated, and GPx is decreased in the saliva of oral LP patients.

Assessment of Uric Acid Level in the Saliva of Patients with Oral Lichen Planus

OBJECTIVE

The aim of this study was to evaluate the level of uric acid (UA) in saliva, which is considered to be an antioxidant defense biomarker against oxidative stress in patients with oral lichen planus (OLP).

SUBJECTS AND METHODS

In this case-control study, 25 OLP patients were included. The reticular form of OLP was verified by a clinical examination with Wickham striae, and other types (erosive, atrophic, ulcerative) were confirmed by histopathological assessment. Thirty healthy individuals matched for age and gender were selected as the control group. In both groups, the Navazesh technique was used to collect the unstimulated saliva. Then, the amount of UA was measured using a Cobas Mira autoanalyzer with a wavelength of 546 nm. The Student t test was used to analyze the data assuming a significance level at <0.05.

RESULTS

Of the 25 patients, the most common type of OLP was erosive (n = 11, 44%), and the most common site of OLP was seen as bilateral in the buccal mucosa (n = 12, 48%). The mean level of salivary UA was significantly lower in the patients with OLP (2.10 ± 0.19 mg/dL) in comparison with the control group (4.80 ± 0.29 mg/dL; p < 0.001).

CONCLUSION

In this study, OLP was associated with a decrease in UA levels in the saliva. Salivary UA as a biomarker could be used for monitoring and treating OLP.

Evaluation of salivary oxidate stress biomarkers, nitric oxide and C-reactive protein in patients with oral lichen planus and burning mouth syndrome

OBJECTIVES

The aim of this study was to evaluate oxidative stress factors and C-reactive protein in the saliva of patients with oral lichen planus (OLP) and burning mouth syndrome (BMS).

METHODS

This consecutive, cross-sectional study included 20 patients with OLP, 19 with burning mouth syndrome (BMS), and 31 control subjects. The oral cavity of each patient was examined and patients responded to a quality of life questionnaire (OHIP-14) and the xerostomia inventory. The following parameters were measured in whole non-stimulated saliva: trolox equivalent antioxidant capacity (TEAC); total antioxidant capacity (TAC); cupric reducing antioxidant capacity (CUPRAC); ferric reducing ability of plasma (FRAP); C-reactive protein (CRP); nitric oxide; nitrates; and nitrites.

RESULTS

The OLP group presented statistically significant differences in reactive oxygen species (ROS) (29 600 cps) in comparison with the control group (39 679 cps) (P < 0.05). In the BMS group, ROS was 29 707 cps with significant difference in comparison with the control group (P < 0.05). Significantly higher salivary nitric oxide (145.7 μmol) and nitrite (141.0 μmol) levels were found in OLP patients in comparison with control group (P < 0.05).

CONCLUSION

Increases in nitric oxide and C-reactive protein were found in the saliva of OLP patients in comparison with BMS and control patients. Further studies are required to confirm these findings.

Urine metabolic profiling for the pathogenesis research of erosive oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) is a relatively common chronic immune-pathological and inflammatory disease and potentially oral precancerous lesion. Erosive OLP patients show the higher rate of malignant transformation than patients with non-erosive OLP. Identifying the potential biomarkers related to erosive OLP may help to understand the pathogenesis of the diseases.

METHODS

Metabolic profiles were compared in control and patient subjects with erosive OLP by using ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF-MS) coupled with pattern recognition methods An integrative analysis was used to identify the perturbed metabolic pathways and pathological processes that may be associated with the disease.

RESULTS

In total, 12 modulated metabolites were identified and considered as the potential biomarkers of erosive OLP. Multiple metabolic pathways and pathological processes were involved in erosive OLP.

CONCLUSION

The dysregulations of these metabolites could be used to explain the pathogenesis of the disease, which could also be the potential therapeutic targets for the disease.

Evaluation of oxidant-antioxidant status in tissue samples in oral cancer: A case control study

Background:

Imbalances between the oxidant-antioxidant status have been implicated in the pathogenesis of several diseases, including cancer. The aim of this study was to evaluate the extent of lipid peroxidation and antioxidants in the tissue samples of oral squamous cell carcinoma (OSCC) patients of different clinical stages in comparison with the healthy controls.

Materials and Methods:

A case-control study was designed with 20 new histopathologically proven oral carcinoma patients and an equal number of age, sex, and tobacco chewing habit matched healthy subjects. Their tissue samples were subjected to evaluation of lipid peroxidation product and antioxidant enzymes, namely, superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and glutathione peroxidase (GPx) using spectrophotometric methods. The data are expressed as mean ± standard deviation. The statistical comparisons between the study groups were performed by independent Student's unpaired t-test and one-way analysis of variance. Post-hoc analysis was performed for within study group comparisons. Karl Pearson correlation was performed for the biochemical parameters within the group and between the groups. For statistically significant correlations, simple linear regression was performed using SPSS (α=0.05).

Results:

Significant reduction in lipid peroxidation (P < 0.001) SOD and CAT (P < 0.001) was observed in the tissue of OSCC patients as compared with the healthy controls. On the other hand, reduced GSH and GPx were significantly increased in tumor samples.

Conclusion:

Reduced lipid peroxidation and increased activity of reduced GSH and GPx provides the suitable environment for the local growth and invasion of the tumor and metastasis in the later stages. Among the antioxidant enzymes, GSH reductase appears to have a profound role in carcinogenesis and thus it can be considered as potential prognostic marker.

Oral lichen planus

Lichen planus is an inflammatory mucocutaneous disease that can affect the skin, hair, nails, and mucosal surfaces. Mucosal sites of involvement include oral, genital, ocular, otic, esophageal, and, less commonly, bladder, nasal, laryngeal, and anal surfaces. Oral lichen planus is a mucosal variant of lichen planus, which tends to affect women more often than men, with a typically more chronic course and potential for significant morbidity. Treatment can be challenging, and there is potentially a low risk of malignant transformation; however, therapeutic benefits can be obtained with various topical and systemic medications. Clinical monitoring is recommended to ensure symptomatic control. Increasing awareness and recognition of this entity have continued to fuel advances in therapy and in our understanding of the disease.

Variability of salivary markers of oxidative stress and antioxidant status in young healthy individuals

OBJECTIVES

Salivary advanced glycation end-products (AGEs), advanced oxidation protein products (AOPP), total antioxidant capacity (TAC), and ferric reducing ability of saliva (FRAS) are increased in various diseases. Little data exist for these markers in the healthy population. The aim of this study was to assess the inter-individual and intra-individual variability of AGEs, AOPP, TAC, and FRAS in the saliva of young healthy individuals.

METHODS

Unstimulated saliva samples were collected from 16 females and 18 males daily over a period of 30 days. Markers were measured using spectrophotometric and spectrofluorometric microplate-based methods.

RESULTS

All salivary markers measured were significantly higher in men than in women (P < 0.05 for AGEs; P < 0.001 for AOPP, TAC, and FRAS). The inter-individual variability was approximately 60% for AGEs and AOPP and 30-40% for TAC and FRAS in both genders. The inter-individual variability of FRAS was higher in men vs. women (P < 0.01). Intra-individual variability ranged from 20% for TAC, to 30% for AGES and FRAS and 45% for AOPP.

DISCUSSION

Intra-individual variability of salivary AGEs, AOPP, TAC, and FRAS indicates that their use is currently limited to large cohort studies. Identifying the underlying factors related to the high inter-individual and intra-individual variability is needed. Sex differences should be considered in future studies.

Salivary and Urinary Total Antioxidant Capacity as Biomarkers of Oxidative Stress in Humans

Total Antioxidant Capacity (TAC) is a biomarker often used in order to investigate oxidative stress in many pathological conditions. Saliva and urine can be collected noninvasively and represent attractive diagnostic fluids for detecting biomarkers of various pathological conditions. The reviewed case-control and intervention studies that measured salivary or urinary TAC revealed that diseases, antioxidant foods, or supplements and age, gender, and lifestyle factors influenced salivary or urinary TAC. Salivary and urinary TAC were particularly affected by oral or renal status, respectively, as well as by infection; therefore these factors must be taken into account in both case-control and intervention studies. Furthermore, some considerations on sample collection and normalization strategies could be made. In particular, unstimulated saliva could be the better approach to measure salivary TAC, whereas 24 h or spontaneous urine collection should be chosen on the basis of the study outcome and of the creatinine clearance. Finally, the uric acid-independent TAC could be the better approach to evaluate red-ox status of body, in particular after nutritional interventions and in diseases associated with hyperuricaemia.

Analysis of plasma lipid peroxidation and antioxidant enzymes status in patients of oral leukoplakia: A case control study

Aims and Objectives:

Imbalances between the oxidant-antioxidant status have been implicated in the pathogenesis of several diseases, including oral cancer. Mostly, all oral cancer lesions are preceded by a stage of premalignancy. The present study aims to evaluate lipid peroxidation and antioxidant status in the venous blood of patients with different clinicopathologic stages of leukoplakia.

Materials and Methods:

A case control study was designed with the inclusion of 20 new cases of histopathologically proven leukoplakia of various clinical stages along with an equal number of positive and negative control individuals. The concentrations of thiobarbituric acid reactive substances and the activities of the antioxidant enzymes, namely superoxide dismutase, reduced glutathione, glutathione peroxidase, and catalase, were estimated in plasma using spectrophotometric methods. The data are expressed as mean ± SD. The statistical comparisons between and within the study groups were performed by one-way analysis of variance followed by post hoc analysis. Karl Pearson correlation was performed for the biochemical parameters within the group and between the groups. For statistically significant correlations, simple linear regression was performed.

Results:

Significant enhanced lipid peroxidation (P < 0.001) with a decrease in antioxidants (P < 0.001) was observed in the venous blood of leukoplakia patients compared with positive as well as negative controls. Accordingly, significant (P < 0.001) pattern of progression in thiobarbituric acid reactive substances levels was observed at various clinical stages among patients of both control groups. Among enzymes, glutathione showed significant (P < 0.001) reduction along the stages on comparison with two control groups.

Conclusion:

Enhanced lipid peroxidation and compromised antioxidant defense in plasma indicate the development of oxidative stress. Among the antioxidant enzymes, reduced glutathione and glutathione Pperoxidase may play a decisive role in malignant transformation.

Evaluation of prolidase activity and oxidative stress in patients with oral lichen planus and oral lichenoid contact reactions

OBJECTIVE

The aim of this study was to evaluate prolidase activity and oxidative stress in patients with oral lichen planus (OLP) and oral lichenoid contact reactions (OLCR) using serum and salivary samples and to compare these biomarkers with each other as well as with a group of healthy subjects in order to be able to opine their role in the estimation of OLP and OLCR.

PATIENTS AND METHODS

Eighteen recently diagnosed patients with OLP, 32 patients with OLCR and 18 healthy controls with matched periodontal status were recruited to the study. Prolidase activity, lipid peroxidation product malondialdehyde (MDA), sialic acid (SA), and advanced oxidation protein products (AOPPs) levels in both serum and saliva were determined. Additionally, salivary flow rate and its buffering capacity were estimated. Statistical analyses were performed using the chi-square test, t-test, Mann-Whitney U-test, and Spearman's rho correlation coefficient.

RESULTS

No statistically significant differences were observed between the study groups and the control group regarding to the basic characteristics and the periodontal status (P > 0.05). There were no statistically significant differences between OLP and OLCR groups regarding to the distribution of lesions' type, severity, and location (P > 0.05). No significant differences were found between the two study groups with regard to Prolidase activity, MDA, SA, and AOPPs (P ˃ 0.05), whereas statistically significant differences were found between the two study groups and the control group with regard to all evaluated parameters except of serum prolidase (P ˂ 0.01). Moderate correlation was found between salivary MDA and the OLP/OLCR lesion severity, whereas a weak correlation was observed between serum SA and the OLP/OLCR lesion severity (P ˂ 0.05).

CONCLUSIONS

The findings of this study suggest an increased prolidase activity and oxidative stress and imbalance in the antioxidant defense system in biological fluids of patients with OLP and OLCR when compared with the healthy subjects. Both OLP and OLCR patients revealed almost similar prolidase activity and oxidative stress levels although these two conditions have different etiopathogenesis.

A case-control study to detect the extent of DNA damage in oral lichen planus and oral lichenoid reactions using comet assay

Aim:

This study aims to quantify the extent of DNA damage in lymphocytes of patients with oral lichen planus (OLP) and oral lichenoid reactions (OLRs) using comet assay.

Methodology:

Lymphocytes from peripheral blood were subjected to alkaline comet assay. Comet length (CL), head diameter (HD), percentage of DNA in head, tail length (TL), percentage of DNA in tail, tail intensity, tail mean and tail moment were compared between study group (OLP and OLR) and control group using Student's t-test. Pearson's correlation coefficient was used to examine the linear association between the variables.

Results:

Significantly higher levels of DNA damage was present in study group as reflected by CL, HD and TL, tail intensity and tail moment with P = 0.0001; percentage of DNA in head and tail with P = 0.02 and tail mean with P = 0.012.

Conclusion:

This study brings out the fact that DNA damage measured by comet assay was greater in the study group when compared to the control group. As a reflection of uniqueness, this study crowns the scenario with respect to early detection and prevention of potentially malignant disorders and the process of malignant transformation.