Effects of oxidized low density lipoprotein on the expression and function of ABCA1 in macrophages

Abstract

In the present study, we examined the regulation of the expression and function of ABCA1 by modified LDL (ox-LDL)in vitro. After incubation with apoA-I for 24 h, RAW264. 7 cells effluxed 37.65% cholesterol loaded by acetyl LDL (ac-LDL), and 9.78% cholesterol in ox-LDL group. The level of ABCA1 mRNA increased about three times either when cells were incubated with 100 μg/mL ac-LDL or with 100 μg/mL ox-LDL. However, the level of ABCA1 protein rose by 1.57 times in ac-LDL group and 1.26 times in ox-LDL group. These results demonstrated that ox-LDL had different effect on the expression and function of ABCA1, ox-LDL might decrease the cholesterol efflux mediated by ABCA1 through other unknown mechanisms.

Keywords

ATP binding cassette transporter A1 / cholesterol efflux / low density lipoprotein / gene expression regulation

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