Relation of photochemical internalization to heat, pH, and Ca2+ ions.
Relation of photochemical internalization to heat, pH, and Ca2+ ions.
复制标题
光化学内化与热、pH 值和 Ca2 离子的关系。
DOI：
10.1111/php.13146
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发表时间：
2019
影响因子：
3.3
通讯作者：
T.
中科院分区：
文献类型：
--
作者：
Soe;T. H.;Nanjo;T.;Watanabe;K.;and Ohtsuki;T.
药物或大分子的低效内体逃逸是实现成功递送至治疗靶标的主要障碍。绕过这一屏障的有效方法是光化学内化（PCI），其使用光和光敏剂用于递送的大分子的内体逃逸。PCI机制与光生单线态氧有关，但其机制尚不清楚。在这项研究中，我们使用细胞穿透肽（CPP）-货物-光敏剂（Alexa 546或Alexa 633）缀合物检查了PCI与热，pH和Ca 2+离子的关系。细胞温度变化实验表明，热（热机制）并不显着有助于光诱导的内体逃逸。V-ATP酶质子泵活性和内体pH上调的抑制表明PCI介导的内体逃逸需要在光照射之前进行内体酸化。光刺激期间CPP-货物-光敏剂和Ca 2+离子的成像显示，细胞内钙增加不是复合物内体逃逸的原因。增加的主要原因是Ca ~（2+）内流。这些发现显示了PCI机制中细胞外和细胞内环境条件的重要性，并丰富了我们对PCI相关细胞变化的理解。
The inefficient endosomal escape of drugs or macromolecules is a major obstacle to achieving successful delivery to therapeutic targets. An efficient approach to circumvent this barrier is photochemical internalization (PCI), which uses light and photosensitizers for endosomal escape of the delivered macromolecules. The PCI mechanism is related to photogenerated singlet oxygen, but the mechanism is still unclear. In this study, we examined the relation of PCI to heat, pH and Ca2+ions using cell penetrating peptide (CPP)‐cargo‐photosensitizer (Alexa546 or Alexa633) conjugates. A cell temperature changing experiment demonstrated that heat (thermal mechanism) does not significantly contribute to the photoinduced endosomal escape. Inhibition of V‐ATPase proton pump activity and endosomal pH upregulation indicated that PCI‐mediated endosomal escape needs endosomal acidification prior to photoirradiation. Imaging of the CPP‐cargo‐photosensitizer and Ca2+ions during photostimulation showed that intracellular calcium increase is not the cause of the endosomal escape of the complex. The increment is mainly due to Ca2+influx. These findings show the importance of extra‐ and intracellular milieu conditions in the PCI mechanism and enrich our understanding of PCI‐related changes in cell.