Triology of nitric oxide, mast cell and stress in pathogenesis of oral lichen planus

Abstract

Introduction: Oral Lichen planus (OLP) is chronic, autoimmune, mucocutaneous disease. Numerous etiological factors have been proposed, but an authoritative and exact source of the disease has not been brought forward. Reactive nitrogen species (RNS), mast cell (MC) and stress are considered to play a key role in inflammation-mediated carcinogenesis generating nitric oxide (NO).

Aim: To evaluate the salivary NO levels, mast cells and stress levels and to correlate them in pathogenesis of OLP.

Materials and methods: The study was conducted using saliva samples of patients. The study consisted of two groups: Group-I constituted the subjects with OLP group (n=25) and group II comprised the control group (n=25). The saliva of the patients was evaluated using Griess Reagent and Spectrophotometer, MC count done by using special stains, and stress levels measured using DASS Scale.

Results: The difference between the means was found to be highly significant (P < 0.05). The intergroup comparison of optical density (OD) values, a mast cell count and stress level was found to be highly significant.

Conclusion: Salivary NO, increase in mast cell count and stress has a definitive role in OLP pathogenesis.

Keywords: Depression anxiety stress scale; mast cells; oral lichen planus; salivary nitric oxide.

Figure 1

(a) Reticular form of OLP: Showing interlacing- Wickham's striae. (b) Atrophic form of OLP-Linear erosive lesion on the vermilion border of lip. The surrounding mucosa is atrophic and erythematous with very faint reticular striations

Figure 2

Atrophic lichen planus; showing a dense juxtaepithelial lymphocytic infiltrate (H & E stain, ×100); Inset: Higher magnification (H & E stain ×400)

Figure 3

Collection of mast cells near the basement membrane (toluidine blue stain, ×100; inset ×400)

Figure 4

Spreading mast cell; showing mast cell granules. Presence of three or more aggregate granules (toluidine blue stain, ×400)

Figure 5

Distribution of various clinical forms of OLP

Figure 6

Comparison of mean of salivary NO levels between two groups

Figure 7

Comparison of mean of mast cells count b/w two groups

Figure 8

Comparison of means of depression, anxiety and stress b/w Groups I-II