Influence of lipoproteins on elastase-type activity of arterial smooth muscle cells in culture

The degradation of arterial elastic fibers occuring in atherosclerosis (ROBERT L. and ROBERT A.M., 1980) appears to be closely related to an increase of elastolytic activity (HORNEBECK W. et al. 1976). The responsible enzymes may well originate from arterial smooth muscle cells (SMC) since the presence of elastase-type proteases has been demonstrated in these cells in culture (BOURDILLON M.C. et al., 1980; BRECHEMIER D. et al., 1980). Lipids were shown to induce structural and functional alterations of elastin, thereby accelerating the fragmentation of elastic fibers by proteolytic enzymes (CLAIRE M. et al., 1976; JORDAN R.E. et al., 1974). Since lipoproteins were shown to be involved in the atherogenic process at the cellular level, (GOLDSTEIN J.L. and BROWN M.S., 1977), it seemed of interest to investigate the possible effect of different lipoprotein fractions on the expression of elastase activity by aorta smooth muscle cells. Results obtained are reported hereafter.