Effect of ATP-binding cassette transporter A1 on cholesterol efflux from cells / 基础医学与临床

ABSTRACT

Objective To investigate the potential change of cellular cholesterol efflux and the functional changes of ABCA1 on macrophages from diabetes animals. Methods High energy diet was given to golden hamster to make animal model of hyperlipidemia. Diabetes was induced by a single intraperitoneal injection of STZ (30 mg/kg). Macrophages were isolated and incubated with apoA-I or 8-br-cAMP in vitro. Cellular cholesterol content was measureal before and after treatment by HPLC. Results Intracellular cholesterol content of diabetic animals was higher than that in high energy diet and normal controls. Expression of ABCA1 mRNA was upregulated in diabetic group after incubation with apoA-I and cAMP. When macrophages were incubated with apoA-I, cholesterol efflux increased with the prolongation of incubation time.The amount of intracellular cholesterol efflux in 3 groups of animals showed the following relationship diabetic animals exceed high energy diet fed animals, and the latter exceeds normal animals. Conclusion Intracellular lipid efflux depends mainly on the presence of extracellular apoA1 as well as membrane ABCA1 protein. The deposition of cholesterol in the macrophage of diabetic and insulin resistant animals may be related to the characteristic changes of quantity and function of apoA1 in these animals.