influence of plasma apolipoprotein A-II concentrations on HDL subclass distribution

Background and aims: To investigate the impact of plasma apoA-II concentrations on the alteration of HDL subclass distribution, and the cooperative effect of apoA-I and apoA-II on it. Methods and results: The apoA-I contents of plasma HDL subclasses were quantified by two-dimensional gel electrophoresis associated with immunodetection for 292 Chinese people. These subjects were divided according to the mean ± 1 SD of apoA-II and apoA-I levels as two cut-points, respectively. Compared with the low-apoA-II group, the apoA-I contents of HDL₃a (in the high group), HDL₃b, and HDL₂b increased strikingly, both in the middle- and high-apoA-II group. The apoA-I contents of all HDL subclasses increased progressively when the apoA-I and apoA-II levels simultaneously or the apoA-I/apoA-II ratio increased, and in comparison to the low-apoA-I-A-II levels group, the apoA-I contents of HDL₂b (115%) increased more significantly than those of preβ₁-HDL (39%) in the high-apoA-I-A-II levels group. Multiple analyses also indicated that the three HDL subclasses, HDL₃a, HDL₃b and HDL₂b, were independently predicted by apoA-II. Conclusion: Excess apoA-II can cause the accumulation of both large-sized HDL₂b and small-sized HDL₃, which implies that apoA-II plays a double role in the HDL maturation metabolism. Meanwhile, the degree of HDL₂b increased significantly relative to that of preβ₁-HDL when apoA-I and apoA-II levels were elevated simultaneously, suggesting that the maturation and metabolism of HDL might be promoted and reverse cholesterol transport might be enhanced.