High glucose, insulin and free fatty acid concentrations synergistically enhance perilipin 3 expression and lipid accumulation in macrophages
High glucose, insulin and free fatty acid concentrations synergistically enhance perilipin 3 expression and lipid accumulation in macrophages
复制标题
高葡萄糖、胰岛素和游离脂肪酸浓度协同增强巨噬细胞中 perilipin 3 的表达和脂质积累
DOI：
10.1016/j.metabol.2013.02.013
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发表时间：
2013-08-01
影响因子：
9.8
通讯作者：
Ikuyama, Shoichiro
中科院分区：
文献类型：
--
作者：
Fan, Bin;Gu, Jian-Qiu;Ikuyama, Shoichiro
Objective.周脂蛋白（PLIN）3，一种细胞内脂滴（LD）相关蛋白，参与泡沫细胞形成。由于在代谢综合征中发现的代谢紊乱，例如高血清葡萄糖、胰岛素和游离脂肪酸（FFA）水平，是促进动脉粥样硬化的主要危险因素，我们使用RAW 264.7细胞研究PLIN 3表达是否受到葡萄糖、胰岛素和油酸（OA）的影响。进行实时PCR和蛋白质印迹法检测PLIN 3或PLIN 2的表达。油红0染色法和脂质分析法测定细胞内甘油三酯（TAG）和胆固醇含量。PLIN 3 mRNA被高浓度葡萄糖或胰岛素单独刺激，但不被OA刺激。任何两种因素的组合在24小时时并不比单独葡萄糖诱发的PLIN 3表达更增强。然而，有趣的是，同时添加所有三种因子协同增强PLIN 3表达。这种协同效应对于PLIN 2 mRNA表达不明显。Src家族酪氨酸激酶和/或磷脂酰肌醇3-激酶的抑制剂，这两者都被胰岛素和FFA信号激活，部分抑制PLIN 3的表达诱导的三个因素的组合。同时加入葡萄糖、胰岛素和OA显著增加了TAG和胆固醇的含量，而PLIN 3的敲低主要降低了TAG的含量。这些结果表明PLIN 3表达被高葡萄糖、胰岛素和FFA浓度协同刺激，与巨噬细胞中的TAG积累平行。这一发现提出了PLIN 3参与巨噬细胞转化为泡沫细胞的新证据（C）2013 Elsevier Inc. All rights reserved.
Objective. Perilipin (PLIN) 3, an intracellular lipid droplet (LD)-associated protein, is implicated in foam cell formation. Since metabolic derangements found in metabolic syndrome, such as high serum levels of glucose, insulin and free fatty acids (FFAs), are major risk factors promoting atherosclerosis, we investigated whether PLIN3 expression is affected by glucose, insulin and oleic acid (OA) using RAW264.7 cells.Methods. Real-time PCR and Western blotting were performed to detect PLIN3 or PLIN2 expression. Oil-red 0 staining and Lipid Analysis were employed to measure cellular content of triacylglycerides (TAG) and cholesterol.Results. PLIN3 mRNA was stimulated by high glucose or insulin concentrations individually, but not by OA. A combination of any two factors did not enhance PLIN3 expression any more than that evoked by glucose alone at 24 h. Interestingly, however, simultaneous addition of all three factors synergistically enhanced the PLIN3 expression. This synergistic effect was not apparent for PLIN2 mRNA expression. Inhibitors of Src family tyrosine kinase and/or phosphatidylinositol 3-kinase, both of which are activated by insulin and FFA signaling, partially suppressed PLIN3 expression induced by the combination of the three factors. While simultaneous addition of glucose, insulin and OA remarkably increased the cellular content of TAG and cholesterol, knocking-down of PLIN3 predominantly reduced TAG content.Conclusions. These results indicate that PLIN3 expression is synergistically stimulated by high glucose, insulin and FFA concentrations, in parallel with TAG accumulation in macrophages. This finding raises new evidence of PLIN3 involvement in conversion of macrophages into foam cells (C) 2013 Elsevier Inc. All rights reserved.