Evaluation of oxidative stress and the microenvironment in oral submucous fibrosis

Single-cell transcriptomics reveals CD8+ T cell structure and developmental trajectories in idiopathic pulmonary fibrosis

Immune cells in the human lung are associated with idiopathic pulmonary fibrosis. However, the contribution of different immune cell subpopulations to the pathogenesis of pulmonary fibrosis remains unclear. We used single-cell RNA sequencing data to investigate the transcriptional profiles of immune cells in the lungs of 5 IPF patients and 3 subjects with non-fibrotic lungs. In an identifiable population of immune cells, we found increased percentage of CD8+ T cells in the T cell subpopulation in IPF. Monocle analyzed the dynamic immune status and cell transformation of CD8+ T cells, as well as the cytotoxicity and exhausted status of CD8+ T cell subpopulations at different stages. Among CD8+ T cells, we found differences in metabolic pathways in IPF and Ctrl, including lipid, amino acid and carbohydrate metabolic. By analyzing the metabolites of CD8+ T cells, we found that different populations of CD8+ T cells in IPF have unique metabolic characteristics, but they also have multiple identical up-regulated or down-regulated metabolites. In IPF, signaling pathways associated with fibrosis were enriched in CD8+ T cells, suggesting that CD8+ T cells may have an important contribution to fibrosis. Finally, we analyzed the interactions between CD8+ T cells and other cells. Together, these studies highlight key features of CD8+ T cells in the pathogenesis of IPF and help to develop effective therapeutic targets.

Role of Enzymic Antioxidants in Mediating Oxidative Stress and Contrasting Wound Healing Capabilities in Oral Mucosal/Skin Fibroblasts and Tissues

Unlike skin, oral mucosal wounds are characterized by rapid healing and minimal scarring, attributable to the "enhanced" healing properties of oral mucosal fibroblasts (OMFs). As oxidative stress is increasingly implicated in regulating wound healing outcomes, this study compared oxidative stress biomarker and enzymic antioxidant profiles between patient-matched oral mucosal/skin tissues and OMFs/skin fibroblasts (SFs) to determine whether superior oral mucosal antioxidant capabilities and reduced oxidative stress contributed to these preferential healing properties. Oral mucosa and skin exhibited similar patterns of oxidative protein damage and lipid peroxidation, localized within the lamina propria/dermis and oral/skin epithelia, respectively. SOD1, SOD2, SOD3 and catalase were primarily localized within epithelial tissues overall. However, SOD3 was also widespread within the lamina propria localized to OMFs, vasculature and the extracellular matrix. OMFs were further identified as being more resistant to reactive oxygen species (ROS) generation and oxidative DNA/protein damage than SFs. Despite histological evaluation suggesting that oral mucosa possessed higher SOD3 expression, this was not fully substantiated for all OMFs examined due to inter-patient donor variability. Such findings suggest that enzymic antioxidants have limited roles in mediating privileged wound healing responses in OMFs, implying that other non-enzymic antioxidants could be involved in protecting OMFs from oxidative stress overall.

A Comprehensive Analysis of the Role of Oxidative Stress in the Pathogenesis and Chemoprevention of Oral Submucous Fibrosis

Oral submucous fibrosis (OSMF) is a chronic oral potentially malignant disorder (OPMD). It is described as a scarring disease of the oral mucosa associated with excess oxidants and insufficient antioxidants. While it is becoming increasingly accepted that oxidative stress results in excessive accumulation of collagen and progressive fibrosis of the submucosal tissues, there is limited data regarding the moderation of oxidative stress to initiate or prevent OSMF. To assess the scope for mechanism-based approaches to prevent or reverse OSMF, we systematically evaluated the existing literature and investigated the role of oxidative stress in the pathogenesis and chemoprevention of OSMF. A search for relevant articles on PubMed and Scopus was undertaken using pre-defined inclusion and exclusion criteria. A total of 78 articles were selected in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The articles eligible for assessment investigated both OSMF and/or oxidative stress biomarkers or specific antioxidants. Both in vitro and human studies consistently demonstrated variations in oxidative stress biomarker levels in OSMF and revealed an increase in oxidative stress, paralleling the development of the disease. Furthermore, the use of antioxidant supplements was overall associated with an improvement in clinical outcomes. Having identified the significance of oxidative stress in OSMF and the therapeutic potential of antioxidant supplements, this scoping review highlights the need for further well-designed studies in the development of mechanism-based interventions for managing OSMF.

Parameters of Oxidative Stress, Vitamin D, Osteopontin, and Melatonin in Patients with Lip, Oral Cavity, and Pharyngeal Cancer

Lip, oral cavity, and pharyngeal cancers (LOCP) constitute a group of rare neoplasms with unfavorable prognosis. So far, not much is known about the role of vitamin D and oxidative stress in the pathogenesis of LOCP in the European population. The aim of the study was to determine the concentrations of vitamin D, osteopontin, melatonin, and malondialdehyde (MDA) as markers of oxidative stress and/or inflammation, as well as the activities of antioxidant enzymes in the course of LOCP. The vitamin D, melatonin, and osteopontin concentrations in blood serum, the MDA levels in erythrocytes and blood plasma, and the activities of superoxide dismutase (SOD-1), catalase (CAT), and glutathione peroxidase (GPx) in erythrocytes were measured in blood samples taken from 25 LOCP patients of middle age (YCG), 20 LOCP elderly patients (OCG), and 25 healthy middle-aged volunteers. In both cancer groups, decreases in vitamin D and CAT, as well as increases in osteopontin and blood plasma MDA, were observed. An increase in GPx activity in YCG and a decrease in melatonin level in OCG were found. The results indicate the vitamin D deficiency and disturbed oxidant-antioxidant homeostasis in LOCP patients. Osteopontin seems to be associated with LOCP carcinogenesis and requires further research.

Potential contribution of ELISA and LFI assays to assessment of the oxidative stress condition based on 8-oxodG biomarker

Immunoassays have been extensively applied in the medical diagnostic field. Enzyme-Linked Immunosorbent Assay (ELISA) and Lateral Flow Immunochemical Assay (LFIA) are methods that have been well established to analysis of clinical substances such as protein, hormones, drugs, identification of antibodies and in the quantification of antigen. Over the past years, the application of these methods has been extended to assess the clinical oxidative stress condition based on monitoring of the 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) biomarker levels. The present manuscript provides an overview of the current immunoassays based on ELISA and LFIA technologies applied for a quantitative analysis of the 8-oxodG. The discussion focuses on the principles of development, improvement and analytical performance of these assays. The relationship of the molecule 8-oxodG as a clinical biomarker of the assessment of the oxidative stress condition is also discussed. Commercially available products to 8-oxodG analysis are also presented.

Oral Submucous Fibrosis: Correlation of Clinical Grading to Various Habit Factors

Objectives:

The aim of this study was to correlate the clinical grading of oral submucous fibrosis (OSMF) with various habit factors and to observe the habit factors associated with the severity of OSMF.

Materials and Methods:

This study was carried out in the Department of Oral Medicine and Radiology, Kalinga Institute of Dental Sciences, Bhubaneswar, Odisha, India. Two hundred patients clinically diagnosed with OSMF were included in the study. The observations were tabulated and subjected to statistical analysis using chi-square test and Spearman’s rank correlation test.

Results:

A total of 200 subjects participated in the study of which 182 were males and 18 were females. Forty-eight males and nine females had Grade I OSMF. One hundred nineteen males and eight females had Grade II OSMF. Fifteen males and only one female had Grade III OSMF. On the basis of functional staging, the total participants in stage I, stage II, and stage III were 185, 14, and 1, respectively. The participants having Grade I, Grade II, and Grade III OSMF with functional staging I were 57, 122, and 6, respectively. The participants having Grade II and Grade III OSMF with functional staging II were 5 and 9, respectively.

Conclusion:

It is alarming that nearly half of the total subjects were in the younger age group and were having OSMF. Also, as the age increased, the subjects were found to be more attracted to consuming areca nut derivatives in the form of betel quid with or without tobacco. It is recommended that community-oriented outreach programs on oral health awareness be developed, emphasizing children who represent the upcoming future, to avoid/quit areca nut and its derivatives.