Thiol/disulfide homeostasis in retinitis pigmentosa patients

Abstract

Purpose: This research is aimed at determination of total oxidant status, total antioxidant status, serum thiol-disulfide, catalase, albumin, ischemia-modified albumin, and ceruloplasmin in patients suffering from retinitis pigmentosa and drawing a comparison with these parameters determined from healthy controls. Methods: The study involved 35 patients of retinitis pigmentosa and 33 controls who were healthy individuals of comparable gender and age. Native thiol, total thiol, disulfide concentration, disulfide/native thiol, disulfide/total thiol, native thiol/total thiol ratios, total oxidant status, total antioxidant status, catalase, ceruloplasmin, albumin, and ischemia-modified albumin were determined from peripheral blood samples and comparison was drawn between the measurements of retinitis pigmentosa and controls. Results: The two groups were similar in gender and age distributions. It was found that retinitis pigmentosa group demonstrated greater total oxidant status, ischemia-modified albumin, and disulfide concentrations as compared to controls (p < 0.001). However, total antioxidant status, catalase, native thiol, total thiol, albumin, and ceruloplasmin of the two groups did not show statistically significant difference (p > 0.05). Moreover, disulfide/total thiol and disulfide/native thiol ratios of the retinitis pigmentosa group were significantly greater in comparison to controls (p < 0.05). Conclusion: The researchers reached the conclusion that thiol oxidation in retinitis pigmentosa patients caused the dynamic thiol/disulfide homeostasis to shift toward the generation of disulfide. This is a novel research that involves analysis of thiol/disulfide homeostasis in retinitis pigmentosa patients using a novel automated assay. The researchers identified the cause for persistent oxidative stress and damage reported in retinitis pigmentosa patients. Still, future research is required for analysis of progression of antioxidant-oxidant state through various retinitis pigmentosa stages.