The activity of cholesterol esterase and ceruloplasmin are inversely related in the serum of men with atherosclerosis obliterans.

BACKGROUND

Ceruloplasmin is a copper-containing (2-glycoprotein and a member of the acute phase reactant family. Parallel changes in ceruloplasmin and copper concentration have been observed in diseases accompanied by severe inflammation, indicating a closely related process. Cholesterol esterase participates in lipoprotein degradation by the hydrolysis of cholesteryl esters in low density lipoproteins (LDL-CE). LDL-CEs are substrates for cholesterol esterase, but can also undergo oxidation by metal ions. The reduction of lipid hydroperoxides has been claimed to play a key role in the control of lipid peroxidation in living systems.

MATERIAL AND METHODS

The experimental group consisted of 16 men with atherosclerosis obliterans of the lower limbs, with 12 healthy male volunteers as a control group. The activity of cholesterol esterase (CEase), ceruloplasmin (Cp), and glutathione peroxidase (GPx), and the concentrations of malonyldialdehyde (MDA) and copper were determined in serum samples.

RESULTS

CEase and Cp activity and copper concentrations were found to be greater in the AO group than in the controls. In addition, CEase and Cp were negatively correlated (r=(0.65, p< or = 0.05) in the serum of men with AO, but not in the controls. Moreover, copper concentration was significantly correlated with the activity of Cp and GPx (r=0.81 and r=0.58, respectively). The reduced GPx activity and the higher MDA concentration found in the AO group indicate a decline in the antioxidative barrier of plasma.

CONCLUSIONS

The results reported here show an inverse relationship between the activities of CEase and Cp in chronic arterial occlusion of the lower limbs, which may reveal the interaction between the antioxidant and lipolytic enzymes.