Human aortic elastin from normal individuals and atherosclerotic patients: lipid and cation contents; susceptibility to elastolysis

Abstract

Aortic elastins, isolated from 30 humans of different ages, were purified by alkaline extraction, and separated into two groups depending on the presence of atherosclerotic plaques and calcification (grades 0 and 1). It was confirmed that the severity of atherosclerosis increases significantly with age ( P < 0.001) and elastin content decreases with atherosclerosis ( P < 0.001). The hydrolysis of the aortic elastins using pancreatic porcine elastase (PPE) was studied. It was observed that increased elastolytic activities are connected with severity of atherosclerosis ( P < 0.001) and both V m and K m apparent kinetic parameters are affected ( P < 0.001). Correlation tests have shown that enzymatic hydrolysis is significantly modified by cholesterol ( P < 0.05), calcium ( P < 0.001) and magnesium concentrations ( P < 0.01) but only cholesterol changes significantly V m and K m parameters.