Relationship between plasma osteopontin and oxidative stress in patients with coronary artery disease

BACKGROUND

It is known that oxidative stress plays an important role in the pathogenesis of atherosclerosis and that an association exists between osteopontin (OPN) and atherosclerosis.

OBJECTIVES

It was proposed that malondialdehyde (MDA), a biomarker of lipid peroxidation and oxidative stress, would be related to plasma OPN levels in patients with coronary artery disease (CAD).

METHODS/RESULTS

Plasma OPN and MDA levels were measured in 71 patients (60 males and 11 females; mean age 61.7 +/- 10 years). Fifty-eight patients had significant CAD (group I) and 13 patients were free of CAD as defined angiographically (group II). Plasma OPN was measured by enzyme-linked immunosorbent assay (ELISA), while MDA was determined spectrophotometrically. Multivariate regression analysis revealed that ln-transformed OPN levels were independently associated with MDA after adjustment for age, hypertension and diabetes mellitus (R(2) = 0.278, p = 0.0004 and beta regression coefficient = 0.252 [standard error = 0.0958], p = 0.011). OPN and MDA levels were higher in patients with diabetes (73.6 +/- 36.2 ng/ml versus 56.1 +/- 30.9 ng/ml, p = 0.02 and 2.5 +/- 0.5 microM versus 2.0 +/- 0.5 microM, p = 0.002, respectively).

CONCLUSIONS

The association between OPN and MDA levels in patients with CAD suggests an interaction between OPN and oxidative stress. This interaction may play a role in the pathogenesis of atherosclerosis.