Oxidized-low density lipoprotein accumulates cholesterol esters via the PKCα-adipophilin-ACAT1 pathway in RAW264.7 cells

Abstract

Oxidized low-density lipoprotein (ox-LDL) can increase the expression of adipophilin and the accumulation of intracellular lipid droplets. However, the detailed mechanisms remain to be fully elucidated. The present study aimed to investigate the mechanism underlying the effect of ox-LDL on the expression of adipophilin and the accumulation of intracellular cholesterol esters. The results revealed that ox-LDL increased the activation of protein kinase C α (PKCα), expression of adipophilin and acyl-coenzymeA: cholesterol acyltransferse 1 (ACAT1) and increased accumulation of intracellular cholesterol esters. In addition, PKCα siRNA abrogated ox-LDL-induced adipophilin, expression of ATAC1 and accumulation of cholesterol esters. Furthermore, ox-LDL increased the accumulation of intracellular cholesterol esters and expression of ACAT1, and this effect were reversed by transfection with adipophilin siRNA. Taken together, these results demonstrated that ox-LDL induces the accumulation of cholesterol esters, which is mediated by the PKCα-adipophilin-ACAT1 pathway.