Ethnicity variation of oxidant-antioxidant enzyme activities in elderly Malaysian diabetic patients with macrovascular complications

Abstract

The present study was designed to examine the ethnicity variation. oxidative stress and the role of oxidant-antioxidant enzymes in the development of macrovascular complications in elderly Malaysian Type 2 diabetic patients. One hundred and eighty elderly (60-80 years) patients with Type 2 diabetes mellitus (DM) of Malay, Chinese and Indian origins and with a history of severe macrovascular complications were studied for various clinical and biochemical parameters. Enzymatic assays in blood samples were estimated spectrophotometrically according to known modified methods. Type 2 DM patients of Indian origin had significantly elevated (P < 0.05) mean fasting blood glucose (FBG) and glycated haemoglobin (HbA1c) levels. Endogenous antioxidant enzymes namely superoxide dismutase (SOD), catalase and glutathione peroxidase (GPX) were significantly decreased (P < 0.05) in Indian patients compared to Malay and Chinese patients. Plasma malondialdehyde (MDA), an indicator for lipid peroxidation was significantly increased (P<0.05) in Indian patients compared to the other ethnic groups. and appears to be positively correlated with FBG, HbA1c duration of disease and age in all the three ethnic groups. No significant difference was found in xanthine oxidase activity between the 3 ethnic groups but there was a mild increase when compared to control subjects (mean = 0.68, SD = 0.42). The evidence only suggests that there is a difference between U1e ethnic groups and the cause is unknown based on the data presented.