Evaluation of Oxidative Stress in Type 2 Diabetics with Vascular Complications

Type 2 diabetes mellitus is a chronic progressive disease characterised by hyperglycaemia and dyslipidemia which leads to the development of vascular complications. Hyperglycaemia overloads glucose metabolic pathways and increases non-enzymatic, auto-oxidative glycosylation and free radical production. Dyslipidemia favours free radical-induced lipid peroxidation and increased deposition of oxidised low density lipoprotein (LDL) cholesterol in the blood vessels resulting in atherosclerosis. Lipid peroxidation, chronic low grade inflammation and oxidative stress have been proven to be closely involved in the development and progression of type 2 diabetes mellitus and its vascular complications. Malondialdehyde (MDA) is a relatively stable lipid peroxidation end-product, frequently used as a marker of lipid peroxidation. Ceruloplasmin (CP) is an antioxidant with ferroxidase activity and an acute phase protein elevated in inflammation. Uric acid (UA) is a major chain breaking antioxidant that protects Vitamin C from oxidation by divalent ions like ferrous ion in the plasma. The purpose of this study was to evaluate oxidative stress in type 2 diabetics with vascular complications and compare the findings with healthy control group and type 2 diabetics without vascular complications. Fasting plasma glucose, glycosylated haemoglobin (HbA1c), lipid profile, MDA, CP and UA were estimated in all study subjects. This study showed statistically significant increase in the levels of fasting plasma glucose, HbA1c, serum cholesterol, serum triglycerides, LDL, VLDL, MDA, CP and UA in type 2 diabetics with vascular complications when compared to healthy control group (p<0.001) and type 2 diabetics without vascular complications (p<0.001). Serum high density lipoprotein (HDL) levels were significantly decreased in the type 2 diabetics with vascular complications when compared to healthy controls (p<0.001) and type 2 diabetics without vascular complications (p<0.001). The study showed statistically significant correlation of oxidative stress markers (MDA, CP and UA) with indicators of glycaemic status (p<0.001) and dyslipidemia (p<0.001). It can be concluded from this study that hyperglycaemia, dyslipidemia, lipid peroxidation, inflammation and oxidative stress are significantly elevated in type 2 diabetics with vascular complications than in normal healthy controls and type 2 diabetics without vascular complications, suggesting their role in the development of vascular complications.