Purpose: Cigarette smoking is a serious risk factor for many diseases, e.g., cardiovascular and pulmonary diseases. It is also a risk factor in several eye diseases, including macula degeneration, glaucoma, and cataract. Ischemic, toxic, and oxidative effects of cigarettes are thought to play an important role in damaging ocular tissue. Furthermore, smoking can cause symptoms of dry-eye disease. The aim of this study was to analyze and compare electrophoretic patterns in tears of smokers (SP), severs smokers (SSP), and nonsmokers (CTRL).
Methods: We examined 105 eyes (SP: n=29, SSP: n=26, CTRL: n=50). Each patient was asked for subjective symptoms such as burning, itching, and foreign-body sensation. Tear proteins were separated by Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Digital image analysis was performed by BioDocAnalyze (Biometra, Göttingen, Germany), with densitometric data files being created for each electrophoretic lane. Data was analyzed by multivariate statistical techniques.
Results: Tear protein patterns in SP ( P<0.05) and SSP ( P<0.05) were different from those of CTRL. There were significantly more protein peaks in the SSP group ( P<0.005) than in CTRL.
Conclusion: Electrophoretic analysis of tear protein patterns could detect changes in tear proteins of smokers in comparison to nonsmokers. These changes were correlated with an increase of dry-eye-related subjective symptoms in smokers. Thus, electrophoretic analysis of tear proteins provided greater insight into the pathogenesis of smoking-induced ocular surface diseases.