Fractional turnover of apolipoprotein(a) and apolipoprotein B-100 within plasma lipoprotein(a) particles in statin-treated patients with elevated and normal Lp(a) concentration

Metabolism. 2019 Jul;96:8-11. doi: 10.1016/j.metabol.2019.04.010. Epub 2019 Apr 14.

Abstract

Context: Lipoprotein(a) [Lp(a)] is a highly atherogenic lipoprotein characterized by apolipoprotein(a) [apo(a)] covalently bounded to apoB-100 (apoB). However, the metabolism of apo(a) and apoB within plasma Lp(a) particles in patients on statins remains unclear.

Methods: The kinetics of Lp(a)-apo(a) and Lp(a)-apoB were determined in 20 patients with elevated Lp(a) (≥0.8 g/L; n = 10) and normal Lp(a) (≤0.3 g/L; n = 10) using stable isotope techniques and compartmental modeling. Plasma apo(a) concentration was measured using liquid chromatography-mass spectrometry. All patients were on statin therapy and were studied in the fasting state.

Results: The fractional catabolic rate (FCR) of Lp(a)-apo(a) was not significantly different from that of Lp(a)-apoB in statin-treated patients with elevated or normal Lp(a) (P > 0.05 in both). Lp(a)-apo(a) FCR was significantly correlated with Lp(a)-apoB in patients with elevated and normal Lp(a) concentrations (r = 0.970 and r = 0.979, respectively; all P < 0.001) with Lin's concordance test showing substantial agreement between the FCRs of Lp(a)-apo(a) and Lp(a)-apoB in patients with elevated and normal Lp(a) concentrations (rc = 0.978 and rc = 0.966, respectively).

Conclusion: Our data indicate that the apo(a) and apoB proteins within Lp(a) particles have similar FCR and are therefore tightly coupled as an Lp(a) holoparticle in statin-treated patients with elevated and normal Lp(a) concentrations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Apolipoprotein B-100 / metabolism*
  • Apolipoproteins A / metabolism*
  • Female
  • Humans
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / therapeutic use*
  • Hyperlipidemias / blood
  • Kinetics
  • Lipoprotein(a) / blood
  • Lipoprotein(a) / metabolism*
  • Male
  • Middle Aged
  • Young Adult

Substances

  • APOB protein, human
  • Apolipoprotein B-100
  • Apolipoproteins A
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • Lipoprotein(a)