[Alterations in the protein content and dysfunction of high-density lipoproteins from hyperhomocysteinemic mice]

Abstract

Aim: The aim of this study was to evaluate the proteic changes in high-density lipoproteins (HDL) induced by methionine-induced hyperhomocysteinemia in mice and its relationship with two of their main antiatherogenic properties.

Methods and results: The oral administration of methionine resulted in an elevation (~8 times) in the plasma concentration of homocysteine. Hyperhomocysteinemia was inversely correlated with the plasma concentration of HDL cholesterol and its main protein component of HDL, apolipoprotein (apo) A-I, respectively. The cholesterol efflux in vivo from macrophages to HDL was decreased in hyperhomocysteinemic mice compared with the control mice. However, the reverse cholesterol transport from macrophages to feces remained unchanged. On the other hand, the ability of HDL from hyperhomocysteinemic mice to prevent the oxidative modification of low-density lipoproteins (LDL) was found decreased and associated with a concomitant reduction in the plasma activity of paraoxonase-1 (PON1) and the plasma concentration of apoA-I, and with a relative reduction in the apoA-IV content (~1.5 times) in the hyperhomocysteinemic HDL, respectively.

Conclusion: The decrease in the ability of HDL from hyperhomocysteinemic mice to prevent LDL from oxidation was associated with a decrease in the apoA-I, PON1 and apoA-IV.

Keywords: High-density lipoproteins; Hiperhomocisteinemia; Hyperhomocysteinemia; Lipoproteínas de alta densidad; Proteomics; Proteómica.