Crystalline Lens Vitamin C Levels in Cataract Surgical Patients

Abstract
To determine the amount of Vitamin C in the lenses of Diabetic and Non-Diabetic Patients with Operable Cataract and ascertain association between Vitamin C levels and Blood Glucose, Glycated Haemoglobin and Intraocular pressure. Thirty Diabetic and Thirty Non-Diabetic Patients cataract surgical patients were matched for age and sex and selected for the study. Plasma fasting blood glucose and whole blood glycated Haemoglobin levels were determined by glucose oxidase enzymatic assay and immunodetection methods respectively. Cataractous lens samples obtained during surgery were weighed and homogenized in 10 volumes of phosphate buffer pH 7 and the resulting homogenate centrifuged at 18,000 g for 5 minutes at 4˚C, separated and supernatant stored at -80˚C. Vitamin C assay was carried out using commercial assay kits. Data was analyzed using SPSS version 23. Age range of participants was 55 - 83 years, with a mean of 66.7 ± 1.8 years. Mean Vitamin C levels in the Diabetic and Non-Diabetic groups were 49.5 μg/g ± 6.47 and 57.02 μg/g ± 8.0 respectively. Although the Non-diabetic group had higher levels of Vitamin C, the difference was not significant. Levels of Vitamin C found in both groups are much lower than what has previously been reported in Literature for clear lenses. There was negative association between Vitamin C and Glucose, Glycated Haemoglobin and Intraocular Pressure. Vitamin C supplementation may be useful in prolonging incidence of cataract in both aging and diabetic Nigerian populations. Larger study involving estimation of Vitamin C in both lens and Plasma samples is desirable.