Apolipoproteins C-II and C-III abnormalities in hyperlipidemic and normolipidemic patients with chronic renal failure

The high incidence of arteriosclerotic disease in patients with chronic ren al failure seems to be due to certain peculiarities in their lipid metaboli sm. These are principally a disorder in the transportation of lipoproteins and a concomitant defect in triglyceride metabolism causing an accumulation of triglyceride-rich-lipoproteins which predispose to atherosclerosis. We studied the disturbances in concentration of apolipoproteins, notably Ap o C-ll and C-lll, which modulate the activity of lipoprotein lipase (LPL), in patients with chronic renal failure (CRF) without replacement therapy an d in hemodialysis patients with and without hyperlipidemia. LPL hydrolyses triglycerides in the lipoprotein-triglyceride (LPRTG) core. The main lipid parameters were measured in 4 groups of normolipidemic and h yperlipidemic patients with and without CRF in comparison with healthy cont rols. We found that the lipolytic activity index (A-I/C-III) was decreased, and Apo C-lll levels were increased, in patients with CRF and patients on HD, including normolipidemic patients. We conclude that high Apo C-lll levels are found in uremic patients before starting dialysis and do not change during dialysis treatment. This increas e could be one of the initial causes of impaired triglyceride catabolism an d LPRTG accumulation even in normolipidemic patients with CRF and may be on e explanation of the high mortality from cardiovascular disease in these pa tients.