【摘要】 目的研究白细胞介素1(IL-1)是否通过蛋白激酶C/丝裂原激活蛋白激酶(PKC/MAPK)信号通路上调泡沫细胞中脂酰CoA胆固醇酯酰转移酶-1(ACAT-1)的表达及活性。方法复苏并培养人单核细胞白血病细胞系/THP-1细胞,与200 nmol/L乙酸肉豆蔻佛波酯(PMA)共孵育48 h,再与氧化低密度脂蛋白(Ox-LDL)共孵育24 h,油红O染色观察胞质内脂质沉积;分别以非放射性酶法和Western blot检测细胞中PKC和MAPK活性;加入PKC和MAPK抑制剂后,以Western blot及液相闪烁计数法检测ACAT-1的蛋白表达及酶活性。结果与PMA共孵育48 h后,THP-1细胞逐渐伸出突起,由圆形、悬浮式生长转变为多角形、梭形,呈阿米巴样贴壁生长;经Ox-LDL诱导24 h后,油红O染色胞质内可见大量吞噬的脂质小滴。与泡沫细胞组相比,泡沫细胞加IL-1组PKC活性、MAPK活性、ACAT-1蛋白表达及活性增加(P<0.05);ACAT-1蛋白表达由4.92±0.11增至5.95±0.12(P<0.05);PKC抑制剂和MAPK抑制剂能显著抑制IL-1上调ACAT-1表达(P<0.05)及活性(P<0.05)的作用。结论 IL-1上调泡沫细胞ACAT-1表达及活性,其作用是通过PKC/MAPK信号通路途径实现的。更多还原

【Abstract】 Objective To investigate potential effect of interleukin-1(IL-1) of increasing Acyl-CoA;on cholesterol acyltransferase-1(ACAT-1) expression and activity in foam cells by protein kinase C(PKC)/mitogen-activated protein kinase(MAPK) signaling pathway.Methods Human monocytic leukemia cell line/(THP-1) was co-cultured with phorbol myristate acetate(PMA) and induced to differentiation into macrophages.The macrophages were cultured with oxidized low density lipoprotein(Ox-LDL) and induced to differentiate into foam cells.Oil red O staining was employed to examine cytoplasm lipid deposition.Activity of PKC was detected by Pep Tag assay for non-radioactive detection and MAPK activity was detected by Western blot in three different groups(the foam cells group,the foam cells IL-1 group,the foam cells IL-1/IL-1 monoclonal antibody group).PKC and MAPK inhibitors were separately added to the three different groups.Western blot and liquid phase scintillation counting were employed to examine the expression of ACAT-1 protein and ACAT-1 activity in different groups,respectively.ResultsTHP-1 cells presented a suspension growth pattern,and showed significant changes in adhensive growth and oval shape.The PKC and MAPK activities in the the foam cells IL-1 group were higher than those in the foam cells group(P<0.05).The expression and activity of ACAT-1 in the the foam cells IL-1 group were higher than those in the foam cells group(P<0.05).After added PKC and MAPK inhibitors,the up-regulation effects of IL-1 on the expression and activity of ACAT-1 were remarkably decreased(P<0.05).Conclusion PKC/MAPK signaling pathway is involved in the IL-1 up-regulation effects on the ACAT-1 expression and activity in the the foam cells.更多还原