Lipid peroxidation and erythrocyte fragility in poorly controlled type 2 diabetes mellitus

Type 2 Diabetes mellitus has been recently found to have evidence of raised inflammatory markers. The chronic inflammation correlates strongly with cardiovascular morbidity markers such as coronary artery disease, stroke and peripheral arterial disease. The chronic inflammation has been linked to the generation of free radicals. The evidence is however inconclusive. Thus there is increased interest in determining the oxidative status of persons with diabetes.

This study was carried out to determine if the plasma oxidative stress status is high in diabetics (especially those that are poorly controlled) and to determine the effect on erythrocyte stability.

Plasma levels of thiobarbituric acid reacting substances (TBARS), an index of lipid peroxidation, and erythrocyte osmotic stability were determined. These were compared between poorly controlled type 2 diabetics and nondiabetic individuals.

The plasma level of TBARS were significantly higher in the plasma of the diabetics: 0.90 +/- 0.09 micromol malondialdehyde (MDA) equivalent L(-1) vs 0.57 +/- 0.02 micromol MDA equivalent L(-1) for control subjects (p=0.002). The diabetic erythrocytes also showed significantly higher fragility: 3.99 +/- 0.37% haemolysis vs 2.11 +/- 0.27% haemolysis for controls (p=0.0004).

Our data shows the occurrence of significantly higher oxidative stress level and osmotic fragility of erythrocytes in the cohort of persons with poorly controlled diabetes mellitus.