出版社:American Society for Biochemistry and Molecular Biology
摘要:Our aim in this study was to investigate the effect of aging on the capacity of HDLs to promote reverse cholesterol transport. HDLs were isolated from plasma of young (Y-HDL) and elderly (E-HDL) subjects. HDL-mediated cholesterol efflux was studied using THP-1 and J774 macrophages. Our results show that E-HDLs present a lower capacity to promote cholesterol efflux than Y-HDLs (41.7 ± 1.4% vs. 49.0 ± 2.2%, respectively; P = 0.013). Reduction in the HDL-mediated cholesterol efflux capacity with aging was more significant with HDL3 than HDL2 (Y-HDL3, 57.3 ± 1% vs. E-HDL3, 50.9 ± 2%; P = 0.012). Moreover, our results show that ABCA1-mediated cholesterol efflux is the more affected pathway in terms of cholesterol-removing capacity. Interestingly, the composition and structure of HDL revealed a reduction in the phosphatidylcholine-sphingomyelin ratio (E-HDL, 32.7 ± 2.7 vs. Y-HDL, 40.0 ± 1.9; P = 0.029) and in the phospholipidic layer membrane fluidity in E-HDL compared with Y-HDL as well as an alteration in the apolipoprotein A-I structure and charge. In conclusion, our results shown that E-HDLs present a reduced capacity to promote cholesterol efflux, principally through the ABCA1 pathway, and this may explain the increase of the incidence of cardiovascular diseases observed during aging.