Abstract
INTRODUCTION: Human paraoxonase (PON1) is a calcium-dependent enzyme physically associated with HDL, and it is believed to contribute to the atheroprotective effect of HDL. The aim of the study was to evaluate PON1 status in patients with atherosclerosis obliterans as an effect of ischemia regarding its activity and phenotype distribution. MATERIAL AND METHODS: The study group consisted of patients with chronic arterial occlusion of the lower limbs due to atherosclerosis obliterans (AO). The patients were divided into two groups according to the degree of ischemia: moderate (MI), and critical (CI). The ratio of the hydrolysis of salt-stimulated PON1 activity to the hydrolysis of phenylacetate was used to assign individuals to one of three possible phenotypes (low activity - A, medium activity - AB, high activity - B). It was observed that PON1 arylesterase activity was affected by ischemia of the lower limbs depending on its degree. RESULTS: The odds ratio and the relative risk analysis showed that the patients with moderate ischemia are much more often characterized by phenotype A than by phenotype B. The low activity phenotype A occurs over twice as often in patients with chronic ischemia of the lower limbs as in individuals from the control group (OR = 2.125; 1.96 to 3.776, p = 0.0143). CONCLUSIONS: This study presents the low activity phenotype A in relation to the risk of ischemia of the lower limbs due to atherosclerosis and shows the potentially important role of PON1 in conclusion of the process leading to intensification of ischemia degree.