Cataract induction by administration of nitroglycerin in cardiac patients through imbalance in redox status

PURPOSE: The objective of this study was to evaluate the role of nitroglycerin in the pathogenesis of cataract. DESIGN: Prospective study. PATIENT AND METHODS: This study was performed in adults from tertiary Saudi Arabian hospitals (34 males and 26 females in each group, aged from 40 to 60 years), who were divided into four groups with an equal number of subjects (control group, cardiac group, idiopathic cataract group, and a group of cardiac patients using nitroglycerin and with cataracts). Fasting glucose concentrations, blood glycated hemoglobin levels, lipid profiles, and levels of nitrite, conjugated dienes (CD), thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), and reduced glutathione (GSH) were determined. RESULTS: Treatment of cardiac patients with nitroglycerin produced an imbalance in their systemic redox status, leading to the development of cataracts, which was reflected by a significant increase in the levels of nitrite, CD, and TBARS and a significant decrease in SOD activity and GSH, compared with idiopathic cataract patients. The results of correlation studies and multiple regression analysis revealed a significant positive correlation between different biochemical parameters (GSH, SOD, TBARS, CD, and nitrite) in the blood and lens in both idiopathic cataract patients and cardiac patients treated with nitroglycerin. CONCLUSION: The study points to the relative and predictive effects of nitric oxide derived from nitroglycerin in the development of cataract in the presence of the oxidative stress induced by nitroglycerin treatment.