Plasma apolipoprotein L concentrations correlate with plasma triglyceridesand cholesterol levels in normolipidemic, hyperlipidemic, and diabetic subjects

Apolipoprotein L is a newly recognized component of human plasma lipoprotei ns, Mainly associated with apoA-I-containing lipoproteins, it is a marker o f distinct HDL subpopulations. In an effort to gain inference as to its as yet unknown function, we studied biological determinants of apoL levels in human plasma. The distribution of apoL in normal subjects is asymmetric, wi th marked skewing toward higher values. No difference was found in apoL con centrations between males and females, but we observed an elevation of apob , in primary hypercholesterolemia (10.1 vs. 8.5 mu g/mL in control), in end ogenous hypertriglyceridemia (13.8 mu g/mL, P < 0.001), combined hyperlipid emia phenotype (18.7 g/mL, P < 0.0001), and in patients with type II diabet es (16.2 mu g/mL, P < 0.02) who were hyperlipidemic.jlr Significant positiv e correlations were observed between apoL and the log of plasma triglycerid es in normolipidemia (0.446, P < 0.0001), endogenous hypertriglyceridemia ( 0.435, P< 0.01), primary hypercholesterolemia (0.66, P < 0.02), combined hy perlipidemia (0.396, P < 0.04), hypoalphalipoproteinemia (0.701, P < 0.005) , and type II diabetes with hyperlipidemia (0.602, P < 0.01). Apolipoprotei n L levels were also correlated with total cholesterol in normolipidemia (0 .257, P < 0.004), endogenous hypertriglyceridemia (0.446, P = 0.001), and n oll-insulin-dependent diabetes mellitus (NIDDM) (0.548, P < 0.02), No signi ficant correlation was found between apoL and body mass index, age, sex, HD L-cholesterol or fasting glucose and glycohemoglobin levels. ApoL levels in plasma of patients with primary cholesteryl ester transfer protein deficie ncy significantly increased (7.1 +/- 0.5 vs. 5.47 +/- 0.27, P< 0.006).