Oxidative stress markers in oral lichen planus

Oral lichen planus (OLP) is a relatively common disorder whose cause is still unknown. Oral cancer is preceded in most cases by pre malignant lesions-leukoplasia, submucous fibrosis and lichen planus. Free radicals and reactive oxygen species play important roles in both pathogenesis of lichen planus and carcinogenesis. Thus monitoring systemic and saliva compounds important for the antioxidant defence (oxidative balance) could be important for the clinician's treatment strategy. Thorough medical management and early active treatment are necessary to improve symptoms and might also be a relevant prevention strategy from squamous cell carcinoma risk, although data to fully support this statement still need investigation. The principal aim of this study was to determine the systemic uric acid, GGT, and albumin levels as well as the levels of uric acid and albumin in 20 patients diagnosed with lichen planus and 20 controls. Extensive medline search failed to reveal any study of this type. Our results showed a significant decrease of saliva (p < 0.005) uric acid and an increase in serum gamma glutamyl transpherase (GGT) (p < 0.01) as well as in the total antioxidant capacity of saliva in patient group with respect to the control one. The preliminary conclusion of our study is that uric acid, the most important salivary antioxidant and GGT could be considered in the future as useful markers of oxidative stress for elaboration of treatment strategy and monitoring.

Could constitute saliva the first line of defence against oxidative stress?

The oral cavity, a very complex and unique milieu due to its dual function, respiratory and digestive, is the only place in the body where the mineralized tissue is exposed to the external environment. In this environment there are complex interactions between various surfaces: host soft and hard tissues, food, air and microorganisms. Saliva is in the middle of this environment and tries to cope with an ever-changing milieu. It includes a large number of inorganic and organic compounds, which act as a "mirror of the body's health". In addition to its other functions, saliva could constitute the first line of defence against oxidative stress. The body contains a number of protective antioxidant mechanisms. Saliva is also rich in antioxidants. We review the current available data and from our laboratory concerning antioxidant capacity of saliva. Substantial data are available in literature on the role of reactive oxygen species and antioxidants in diseases, but few information is available on oral pathology. Due to its composition and functions, saliva could have a significant role in controlling and/or modulating oxidative damages in the oral cavity.