STATUS OF ENZYMATIC ANTIOXIDANTS IN EYE LENS EXTRACTED FROM CATARACTOUS SUBJECTS
Keywords:
cataractous lens, Enzymatic antioxidants, Cataractous subjects, Apparently normal, diabetic, HypertensiveAbstract
Objectives: Cataract is a common kind of blindness prevailing in India. Eye lens is normally exposed to toxic elements of the surroundings, leading to the formation of free radicals. In normal conditions, the presence of antioxidants may help to counteract the progression of free radical formation in an eye lens. Hence, it was requisite to assess the activities of enzymatic antioxidants in the eye lens extracted from cataractous subjects.
Methods: The cataractous lens samples of 120 subjects were collected from the ophthalmic centres in and around Coimbatore. The subjects were categorised into apparently normal cataract men (ACM), apparently normal cataract women (ACW), diabetic cataract men (DCM), diabetic cataract women (DCW), hypertensive cataract men (HCM) and hypertensive cataract women (HCW) with each group consisting of 20 samples. Activities of enzymatic antioxidants namely superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) were assessed in the cataractous lens samples from the selected subjects. Data was interpreted using SPSS 16.0 software package.
Results: The activities of SOD and CAT were found to be significantly decreased (p<0.05) in all the five groups when compared to apparently normal cataract men. Enzymes of glutathione system exhibited a significant variation (p<0.05) in their activity in the cataractous eye lens extracted from diabetic and hypertensive cataract women in comparison to apparently normal cataract men. A significant decrease (p<0.05) in the activities of GR and GST was also observed in the cataractous eye lens extracted from diabetic and hypertensive cataract men when compared to the subjects of ACM group.
Conclusion: The outcome of the study suggested that cataractous subjects with clinical complications were much disposed to the reactive oxygen species and more affected than the apparently normal cataractous subjects.
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