Echesabal-Chen Jing, Huang Kun, Vojtech Lucia, Oladosu Olanrewaju, Esobi Ikechukwu, Sachdeva Rakesh, Vyavahare Naren, Jo Hanjoong, Stamatikos Alexis
Department of Food, Nutrition and Packaging Sciences, Clemson University, Clemson, SC 29634, USA.
Department of Obstetrics & Gynecology, University of Washington, Seattle, WA 98109, USA.
Curr Issues Mol Biol. 2023 Jul 4;45(7):5631-5644. doi: 10.3390/cimb45070355.
Atherosclerosis is driven by intimal arterial macrophages accumulating cholesterol. Atherosclerosis also predominantly occurs in areas consisting of proinflammatory arterial endothelial cells. At time of writing, there are no available clinical treatments that precisely remove excess cholesterol from lipid-laden intimal arterial macrophages. Delivery of anti-miR-33a-5p to macrophages has been shown to increase apoAI-mediated cholesterol efflux via ABCA1 upregulation but delivering transgenes to intimal arterial macrophages is challenging due to endothelial cell barrier integrity. In this study, we aimed to test whether lipoparticles targeting proinflammatory endothelial cells can participate in endothelial cell-derived exosome exploitation to facilitate exosome-mediated transgene delivery to macrophages. We constructed lipoparticles that precisely target the proinflammatory endothelium and contain a plasmid that expresses XMOTIF-tagged anti-miR-33a-5p (LP-pXMoAntimiR33a5p), as XMOTIF-tagged small RNA demonstrates the capacity to be selectively shuttled into exosomes. The cultured cells used in our study were immortalized mouse aortic endothelial cells (iMAECs) and RAW 264.7 macrophages. From our results, we observed a significant decrease in miR-33a-5p expression in macrophages treated with exosomes released basolaterally by LPS-challenged iMAECs incubated with LP-pXMoAntimiR33a5p when compared to control macrophages. This decrease in miR-33a-5p expression in the treated macrophages caused ABCA1 upregulation as determined by a significant increase in ABCA1 protein expression in the treated macrophages when compared to the macrophage control group. The increase in ABCA1 protein also simulated ABCA1-dependent cholesterol efflux in treated macrophages-as we observed a significant increase in apoAI-mediated cholesterol efflux-when compared to the control group of macrophages. Based on these findings, strategies that involve combining proinflammatory-targeting lipoparticles and exploitation of endothelial cell-derived exosomes appear to be promising approaches for delivering atheroprotective transgenes to lipid-laden arterial intimal macrophages.
动脉粥样硬化是由内膜动脉巨噬细胞积累胆固醇所驱动的。动脉粥样硬化也主要发生在由促炎动脉内皮细胞组成的区域。在撰写本文时，尚无能够精确地从富含脂质的内膜动脉巨噬细胞中清除过量胆固醇的临床治疗方法。已证明将抗miR - 33a - 5p递送至巨噬细胞可通过上调ABCA1来增加载脂蛋白AI介导的胆固醇流出，但由于内皮细胞屏障的完整性，将转基因递送至内膜动脉巨噬细胞具有挑战性。在本研究中，我们旨在测试靶向促炎内皮细胞的脂质颗粒是否能够参与利用内皮细胞衍生的外泌体，以促进外泌体介导的转基因递送至巨噬细胞。我们构建了精确靶向促炎内皮且包含表达XMOTIF标签的抗miR - 33a - 5p的质粒的脂质颗粒（LP - pXMoAntimiR33a）；因为XMOTIF标签的小RNA显示出能够选择性地穿梭到外泌体中的能力。我们研究中使用的培养细胞是永生化小鼠主动脉内皮细胞（iMAECs）和RAW 264.7巨噬细胞。从我们的结果来看，与对照巨噬细胞相比，用与LP - pXMoAntimiR33a共孵育的经LPS刺激的iMAECs从基底外侧释放的外泌体处理的巨噬细胞中，miR - 33a - 5p表达显著降低。与巨噬细胞对照组相比，处理后的巨噬细胞中ABCA1蛋白表达显著增加，这表明处理后的巨噬细胞中miR - 33a - 5p表达的降低导致了ABCA1上调。ABCA蛋白的增加还模拟了处理后巨噬细胞中ABCA1依赖性胆固醇流出——与巨噬细胞对照组相比，我们观察到载脂蛋白AI介导的胆固醇流出显著增加。基于这些发现，涉及结合靶向促炎的脂质颗粒和利用内皮细胞衍生外泌体的策略似乎是将抗动脉粥样硬化转基因递送至富含脂质的动脉内膜巨噬细胞的有前景的方法。
