摘要
目的 探讨PKC信号途径对oxLDL和acLDL诱导的小鼠巨噬细胞ABCAl表达的影响。方法 分别以100μg/ml acLDL和oxLDL温育小鼠巨噬细胞系RAW264.7细胞24 h,同时加入PKC信号途径的激活剂(PMA)或抑制剂(GF109203X),应用胆固醇外排实验、半定量RT-PCR和Western印迹,检测小鼠巨噬细胞内ABCAl功能、mRNA及蛋白质表达的水平。结果 1.0 μmol/L GF109203X可分别使aeLDL孵育组的胆固醇外排率下降至对照组的56.0％,ABCA1 mRNA水平下降至(54.0±8.2)％,蛋白质水平下降至(68.1±2.0)％;oxLDL孵育组的胆固醇外排率下降至对照组的47.0％,ABCA1 mRNA水平下降至(43.0±5.0)％,蛋白质水平下降至(73.0±10.0)％。160 nmol/L PMA作用24 h可分别使acLDL孵育组的胆固醇外排率升高至134.0％,oxLDL孵育组升高至125.1％;ABCA1 mRNA水平升高至(211.0±17.0)％,蛋白质水平升高至(305.0±21.0)％。结论 PKC信号途径在oxLDL和acLDL对小鼠巨噬细胞内ABCA1表达调控中发挥作用,该信号途径的激活可上调ABCA1的表达,促进ABCA1介导的胆固醇外排。
Objective To investigate the role of PKC signaling pathway in ABCA1 expression in murine macrophage induced by oxLDL and acLDL. Methods A murine macrophage cell line, RAW264. 7, were incubated with 100 μg/ml acLDL or oxLDL for 24 h. During this period, PKC agonist (PMA) or antiagonist (GF109203X) were added. The function of ABCA1 was examined by cholesterol efflux experiment, while mRNA and protein level of ABCA1 were detected by semi-quantitative RT-PCR and Western blot, respectively. Results In cells incubated with acLDL, 1.0 μmol/L GF109203X reduced cholesterol efflux to 56. 0% , ABCA1 mRNA to (54. 0±8. 2)% , and ABCA1 protein to (68. 1±2. 0)% , respectively, compared with control. The same reactions were seen when cells were incubated with oxLDL and 1. 0μmol/L GF109203X, with cholesterol efflux decreased to 47. 0% , and ABCA1 mRNA decreased to (43.0±5.0)% , and ABCA1 protein to (73.0±10. 0)% , respectively. Conversely, 160 nmol/L PMA increased cholesterol efflux to a maximum of 134. 0% in acLDL group and 125. 1% in oxLDL group. And PMA also increased AB-CA1 mRNA to (211. 0± 17. 0)% , ABCA1 protein to (305. 0±21. 0)% , respectively, compared with control. Conclusions PKC signaling pathway is involved in the regulation of ABCA1 expression in murine macrophages induced by acLDL and oxLDL. Activation of PKC signaling results in up-regulation of ABCA1 expression and enhances ABCA1-mediated cholesterol efflux in macrophages.
出处
《医学分子生物学杂志》
CAS
CSCD
2004年第3期146-151,157,共7页
Journal of Medical Molecular Biology
