ENHANCED CAVEOLAE-MEDIATED ENDOCYTOSIS BY DIAGNOSTIC ULTRASOUND IN VITRO
ENHANCED CAVEOLAE-MEDIATED ENDOCYTOSIS BY DIAGNOSTIC ULTRASOUND IN VITRO
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DOI：
10.1016/j.ultrasmedbio.2008.07.011
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发表时间：
2009-01-01
影响因子：
2.9
通讯作者：
Picano, Eugenio
中科院分区：
文献类型：
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作者：
Lioneiti, Vincenzo;Fittipaldi, Antonio;Picano, Eugenio
细胞内皮通透性的调节是靶向递送标记物和治疗性大分子的理想目标;然而，其潜在机制仍然知之甚少。在此，我们假设，在当前临床诊断使用的频率和强度范围内，超声（US）选择性增强小窝内吞作用可能导致较高的内皮渗透性。为了评估自由基在这种现象中的作用，我们将大陆人内皮细胞暴露于脉冲诊断US 30分钟，机械指数（MI）为0.5和1.2，使用1.6 MHz心脏US扫描，内皮细胞未暴露于US作为对照。在这里，我们表明，MI为1.2的脉冲诊断超声（高机械指数超声[HMIUS]）能够选择性地增强重组谷胱甘肽-S-转移酶（GST）-Tat 11-EGFP融合蛋白（26 +/- 1 vs. 11.6 +/- A.U，p < 0.001 vs.对照）的内皮小窝内化，而不破坏质膜完整性。此外，与对照相比，Nil为0.5的脉冲诊断超声（低机械指数超声）没有增加小窝内吞作用（11.4 +/- 1.2 vs. 11.6 1）。自由基生成抑制剂，如过氧化氢酶和超氧化物歧化酶，减少了49.29%的因子HMIUS诱导的小窝内化;最后，HMIUS诱导的小窝内吞被认为是与一个显着增加的磷酸化酪氨酸-14-小窝蛋白1，丝氨酸1177-eNOS和Thr 202/Tyr 204-ERK 1/2相比，控制。这些研究结果表明，HMIUS照射人内皮细胞如何引起小窝依赖性渗透性的选择性增强，部分由自由基的产生介导，诱导小窝相关蛋白磷酸化的显着增加。因此，诊断US的使用可以潜在地用作通过使用更高水平的US能量来驱动细胞外肽的小窝运输的佐剂。
The modulation of cellular endothelial permeability is a desirable goal for targeted delivery of labels and therapeutic macromolecules; the underlying mechanisms, however, remains poorly understood. Here, we hypothesize that a higher endothelial permeability may result as an outcome of selective enhancement of caveolar endocytosis by ultrasound (US), in the frequency and intensity range of current clinical diagnostic use. To assess the role of free radicals in this phenomenon, we exposed continent human endothelial cells to pulsed diagnostic US for 30 min, with a mechanical index (MI) of 0.5 and 1.2, using a 1.6-MHz cardiac US scan, and endothelial cells not exposed to US were used as control. Here we show that pulsed diagnostic US with a MI of 1.2 (high mechanical index ultrasound [HMIUS]) were able to selectively enhance endothelial caveolar internalization (of recombinant glutathione-S-transferase (GST)-Tat11-EGFP fusion protein (26 +/- 1 vs. 11.6 +/- A.U, p < 0.001 vs. control), without disruption of plasma membrane integrity. Moreover, pulsed diagnostic US with a Nil of 0.5 (low mechanical index ultrasound) did not increase caveolar endocytosis compared with control (11.4 +/- 1.2 vs. 11.6 1). Free-radical generation inhibitors, such as catalase and superoxide dismutase, reduced the HMIUS-induced caveolar internalization by a 49.29% factor; finally, HMIUS-induced caveolar endocytosis was found to be associated with a significant increase in the phosphorylation of tyr-14-caveolin1, ser1177-eNOS and Thr202/Tyr204-ERK1/2 compared with control. These findings show how HMIUS irradiation of human endothelial cells cause a selective enhancement of caveolar-dependent permeability, partially mediated by free radicals generation, inducing a marked increase of phosphorylation of caveolar-related proteins. Thus, the use of diagnostic US could potentially be used as an adjuvant to drive caveolar traffic of extracellular peptides by using a higher level of US energy.