Tomasz Wielkoszyński

Arylesterase and paraoxonase activity of paraoxonase (PON1) affected by ischemia in the plasma of patients with arterial occlusion of the lower limbs.

OBJECTIVES The aim of the study was to evaluate the effect of different degrees of chronic ischemia of the lower limbs on PON1 activity in plasma, in relation to different substrates. DESIGN AND METHODS The studied group consisted of patients with chronic arterial occlusion of the lower limbs due to atherosclerosis. The paraoxonase and arylesterase activities of PON1 were measured according to the Karen Gan method. RESULTS PON1 arylesterase activity was affected by ischemia of the lower limbs depending on its degree. In the group with critical ischemia decreased PON1 activity was observed in comparison with that in the moderate ischemia group and the control group (50.05+/-21.40 U/mL and 82.59+/-29.27 U/mL, 85.30+/-35.05 U/mL, respectively). CONCLUSIONS The results revealed a reverse relationship between PON1 activity and the progress of atherosclerosis to the ischemic level. The present study demonstrates, for the first time, that the arylesterase activity of PON1 is affected by critical ischemia of the lower limbs.

Effects of Oxidized Cooking Oil and α-Lipoic Acid on Liver Antioxidants: Enzyme Activities and Lipid Peroxidation in Rats Fed a High Fat Diet

The effects of administration of oxidized rapeseed oil and α-lipoic acid on activities of hepatic antioxidant enzymes and lipid peroxidation were studied in laboratory rats. There was an increase of the activities of superoxide dismutase, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase in rats fed a high fat diet to which 10% oxidized oil was added. Administration of α-lipoic acid resulted in a decrease of the activities of these enzymes. Addition of oxidized oil also resulted in increased production of oxygen radicals, evidenced by elevated malondialdehyde production. Such effect was counteracted by administration of α-lipoic acid.